xref: /openbmc/linux/drivers/tty/synclink_gt.c (revision 3a35093a)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22 
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36 
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44 
45 
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74 
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80 
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86 
87 /*
88  * module identification
89  */
90 static char *driver_name     = "SyncLink GT";
91 static char *slgt_driver_name = "synclink_gt";
92 static char *tty_dev_prefix  = "ttySLG";
93 MODULE_LICENSE("GPL");
94 #define MGSL_MAGIC 0x5401
95 #define MAX_DEVICES 32
96 
97 static const struct pci_device_id pci_table[] = {
98 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
102 	{0,}, /* terminate list */
103 };
104 MODULE_DEVICE_TABLE(pci, pci_table);
105 
106 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
107 static void remove_one(struct pci_dev *dev);
108 static struct pci_driver pci_driver = {
109 	.name		= "synclink_gt",
110 	.id_table	= pci_table,
111 	.probe		= init_one,
112 	.remove		= remove_one,
113 };
114 
115 static bool pci_registered;
116 
117 /*
118  * module configuration and status
119  */
120 static struct slgt_info *slgt_device_list;
121 static int slgt_device_count;
122 
123 static int ttymajor;
124 static int debug_level;
125 static int maxframe[MAX_DEVICES];
126 
127 module_param(ttymajor, int, 0);
128 module_param(debug_level, int, 0);
129 module_param_array(maxframe, int, NULL, 0);
130 
131 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
132 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
133 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
134 
135 /*
136  * tty support and callbacks
137  */
138 static struct tty_driver *serial_driver;
139 
140 static int  open(struct tty_struct *tty, struct file * filp);
141 static void close(struct tty_struct *tty, struct file * filp);
142 static void hangup(struct tty_struct *tty);
143 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios);
144 
145 static int  write(struct tty_struct *tty, const unsigned char *buf, int count);
146 static int put_char(struct tty_struct *tty, unsigned char ch);
147 static void send_xchar(struct tty_struct *tty, char ch);
148 static void wait_until_sent(struct tty_struct *tty, int timeout);
149 static int  write_room(struct tty_struct *tty);
150 static void flush_chars(struct tty_struct *tty);
151 static void flush_buffer(struct tty_struct *tty);
152 static void tx_hold(struct tty_struct *tty);
153 static void tx_release(struct tty_struct *tty);
154 
155 static int  ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
156 static int  chars_in_buffer(struct tty_struct *tty);
157 static void throttle(struct tty_struct * tty);
158 static void unthrottle(struct tty_struct * tty);
159 static int set_break(struct tty_struct *tty, int break_state);
160 
161 /*
162  * generic HDLC support and callbacks
163  */
164 #if SYNCLINK_GENERIC_HDLC
165 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
166 static void hdlcdev_tx_done(struct slgt_info *info);
167 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size);
168 static int  hdlcdev_init(struct slgt_info *info);
169 static void hdlcdev_exit(struct slgt_info *info);
170 #endif
171 
172 
173 /*
174  * device specific structures, macros and functions
175  */
176 
177 #define SLGT_MAX_PORTS 4
178 #define SLGT_REG_SIZE  256
179 
180 /*
181  * conditional wait facility
182  */
183 struct cond_wait {
184 	struct cond_wait *next;
185 	wait_queue_head_t q;
186 	wait_queue_entry_t wait;
187 	unsigned int data;
188 };
189 static void init_cond_wait(struct cond_wait *w, unsigned int data);
190 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w);
191 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *w);
192 static void flush_cond_wait(struct cond_wait **head);
193 
194 /*
195  * DMA buffer descriptor and access macros
196  */
197 struct slgt_desc
198 {
199 	__le16 count;
200 	__le16 status;
201 	__le32 pbuf;  /* physical address of data buffer */
202 	__le32 next;  /* physical address of next descriptor */
203 
204 	/* driver book keeping */
205 	char *buf;          /* virtual  address of data buffer */
206     	unsigned int pdesc; /* physical address of this descriptor */
207 	dma_addr_t buf_dma_addr;
208 	unsigned short buf_count;
209 };
210 
211 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
212 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
213 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
214 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
215 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
216 #define desc_count(a)      (le16_to_cpu((a).count))
217 #define desc_status(a)     (le16_to_cpu((a).status))
218 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
219 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
220 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
221 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
222 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
223 
224 struct _input_signal_events {
225 	int ri_up;
226 	int ri_down;
227 	int dsr_up;
228 	int dsr_down;
229 	int dcd_up;
230 	int dcd_down;
231 	int cts_up;
232 	int cts_down;
233 };
234 
235 /*
236  * device instance data structure
237  */
238 struct slgt_info {
239 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
240 	struct tty_port port;
241 
242 	struct slgt_info *next_device;	/* device list link */
243 
244 	int magic;
245 
246 	char device_name[25];
247 	struct pci_dev *pdev;
248 
249 	int port_count;  /* count of ports on adapter */
250 	int adapter_num; /* adapter instance number */
251 	int port_num;    /* port instance number */
252 
253 	/* array of pointers to port contexts on this adapter */
254 	struct slgt_info *port_array[SLGT_MAX_PORTS];
255 
256 	int			line;		/* tty line instance number */
257 
258 	struct mgsl_icount	icount;
259 
260 	int			timeout;
261 	int			x_char;		/* xon/xoff character */
262 	unsigned int		read_status_mask;
263 	unsigned int 		ignore_status_mask;
264 
265 	wait_queue_head_t	status_event_wait_q;
266 	wait_queue_head_t	event_wait_q;
267 	struct timer_list	tx_timer;
268 	struct timer_list	rx_timer;
269 
270 	unsigned int            gpio_present;
271 	struct cond_wait        *gpio_wait_q;
272 
273 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
274 
275 	struct work_struct task;
276 	u32 pending_bh;
277 	bool bh_requested;
278 	bool bh_running;
279 
280 	int isr_overflow;
281 	bool irq_requested;	/* true if IRQ requested */
282 	bool irq_occurred;	/* for diagnostics use */
283 
284 	/* device configuration */
285 
286 	unsigned int bus_type;
287 	unsigned int irq_level;
288 	unsigned long irq_flags;
289 
290 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
291 	u32 phys_reg_addr;
292 	bool reg_addr_requested;
293 
294 	MGSL_PARAMS params;       /* communications parameters */
295 	u32 idle_mode;
296 	u32 max_frame_size;       /* as set by device config */
297 
298 	unsigned int rbuf_fill_level;
299 	unsigned int rx_pio;
300 	unsigned int if_mode;
301 	unsigned int base_clock;
302 	unsigned int xsync;
303 	unsigned int xctrl;
304 
305 	/* device status */
306 
307 	bool rx_enabled;
308 	bool rx_restart;
309 
310 	bool tx_enabled;
311 	bool tx_active;
312 
313 	unsigned char signals;    /* serial signal states */
314 	int init_error;  /* initialization error */
315 
316 	unsigned char *tx_buf;
317 	int tx_count;
318 
319 	char *flag_buf;
320 	bool drop_rts_on_tx_done;
321 	struct	_input_signal_events	input_signal_events;
322 
323 	int dcd_chkcount;	/* check counts to prevent */
324 	int cts_chkcount;	/* too many IRQs if a signal */
325 	int dsr_chkcount;	/* is floating */
326 	int ri_chkcount;
327 
328 	char *bufs;		/* virtual address of DMA buffer lists */
329 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
330 
331 	unsigned int rbuf_count;
332 	struct slgt_desc *rbufs;
333 	unsigned int rbuf_current;
334 	unsigned int rbuf_index;
335 	unsigned int rbuf_fill_index;
336 	unsigned short rbuf_fill_count;
337 
338 	unsigned int tbuf_count;
339 	struct slgt_desc *tbufs;
340 	unsigned int tbuf_current;
341 	unsigned int tbuf_start;
342 
343 	unsigned char *tmp_rbuf;
344 	unsigned int tmp_rbuf_count;
345 
346 	/* SPPP/Cisco HDLC device parts */
347 
348 	int netcount;
349 	spinlock_t netlock;
350 #if SYNCLINK_GENERIC_HDLC
351 	struct net_device *netdev;
352 #endif
353 
354 };
355 
356 static MGSL_PARAMS default_params = {
357 	.mode            = MGSL_MODE_HDLC,
358 	.loopback        = 0,
359 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
360 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
361 	.clock_speed     = 0,
362 	.addr_filter     = 0xff,
363 	.crc_type        = HDLC_CRC_16_CCITT,
364 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
365 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
366 	.data_rate       = 9600,
367 	.data_bits       = 8,
368 	.stop_bits       = 1,
369 	.parity          = ASYNC_PARITY_NONE
370 };
371 
372 
373 #define BH_RECEIVE  1
374 #define BH_TRANSMIT 2
375 #define BH_STATUS   4
376 #define IO_PIN_SHUTDOWN_LIMIT 100
377 
378 #define DMABUFSIZE 256
379 #define DESC_LIST_SIZE 4096
380 
381 #define MASK_PARITY  BIT1
382 #define MASK_FRAMING BIT0
383 #define MASK_BREAK   BIT14
384 #define MASK_OVERRUN BIT4
385 
386 #define GSR   0x00 /* global status */
387 #define JCR   0x04 /* JTAG control */
388 #define IODR  0x08 /* GPIO direction */
389 #define IOER  0x0c /* GPIO interrupt enable */
390 #define IOVR  0x10 /* GPIO value */
391 #define IOSR  0x14 /* GPIO interrupt status */
392 #define TDR   0x80 /* tx data */
393 #define RDR   0x80 /* rx data */
394 #define TCR   0x82 /* tx control */
395 #define TIR   0x84 /* tx idle */
396 #define TPR   0x85 /* tx preamble */
397 #define RCR   0x86 /* rx control */
398 #define VCR   0x88 /* V.24 control */
399 #define CCR   0x89 /* clock control */
400 #define BDR   0x8a /* baud divisor */
401 #define SCR   0x8c /* serial control */
402 #define SSR   0x8e /* serial status */
403 #define RDCSR 0x90 /* rx DMA control/status */
404 #define TDCSR 0x94 /* tx DMA control/status */
405 #define RDDAR 0x98 /* rx DMA descriptor address */
406 #define TDDAR 0x9c /* tx DMA descriptor address */
407 #define XSR   0x40 /* extended sync pattern */
408 #define XCR   0x44 /* extended control */
409 
410 #define RXIDLE      BIT14
411 #define RXBREAK     BIT14
412 #define IRQ_TXDATA  BIT13
413 #define IRQ_TXIDLE  BIT12
414 #define IRQ_TXUNDER BIT11 /* HDLC */
415 #define IRQ_RXDATA  BIT10
416 #define IRQ_RXIDLE  BIT9  /* HDLC */
417 #define IRQ_RXBREAK BIT9  /* async */
418 #define IRQ_RXOVER  BIT8
419 #define IRQ_DSR     BIT7
420 #define IRQ_CTS     BIT6
421 #define IRQ_DCD     BIT5
422 #define IRQ_RI      BIT4
423 #define IRQ_ALL     0x3ff0
424 #define IRQ_MASTER  BIT0
425 
426 #define slgt_irq_on(info, mask) \
427 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
428 #define slgt_irq_off(info, mask) \
429 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
430 
431 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
432 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
433 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
434 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
435 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
436 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
437 
438 static void  msc_set_vcr(struct slgt_info *info);
439 
440 static int  startup(struct slgt_info *info);
441 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
442 static void shutdown(struct slgt_info *info);
443 static void program_hw(struct slgt_info *info);
444 static void change_params(struct slgt_info *info);
445 
446 static int  register_test(struct slgt_info *info);
447 static int  irq_test(struct slgt_info *info);
448 static int  loopback_test(struct slgt_info *info);
449 static int  adapter_test(struct slgt_info *info);
450 
451 static void reset_adapter(struct slgt_info *info);
452 static void reset_port(struct slgt_info *info);
453 static void async_mode(struct slgt_info *info);
454 static void sync_mode(struct slgt_info *info);
455 
456 static void rx_stop(struct slgt_info *info);
457 static void rx_start(struct slgt_info *info);
458 static void reset_rbufs(struct slgt_info *info);
459 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
460 static void rdma_reset(struct slgt_info *info);
461 static bool rx_get_frame(struct slgt_info *info);
462 static bool rx_get_buf(struct slgt_info *info);
463 
464 static void tx_start(struct slgt_info *info);
465 static void tx_stop(struct slgt_info *info);
466 static void tx_set_idle(struct slgt_info *info);
467 static unsigned int free_tbuf_count(struct slgt_info *info);
468 static unsigned int tbuf_bytes(struct slgt_info *info);
469 static void reset_tbufs(struct slgt_info *info);
470 static void tdma_reset(struct slgt_info *info);
471 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
472 
473 static void get_signals(struct slgt_info *info);
474 static void set_signals(struct slgt_info *info);
475 static void enable_loopback(struct slgt_info *info);
476 static void set_rate(struct slgt_info *info, u32 data_rate);
477 
478 static int  bh_action(struct slgt_info *info);
479 static void bh_handler(struct work_struct *work);
480 static void bh_transmit(struct slgt_info *info);
481 static void isr_serial(struct slgt_info *info);
482 static void isr_rdma(struct slgt_info *info);
483 static void isr_txeom(struct slgt_info *info, unsigned short status);
484 static void isr_tdma(struct slgt_info *info);
485 
486 static int  alloc_dma_bufs(struct slgt_info *info);
487 static void free_dma_bufs(struct slgt_info *info);
488 static int  alloc_desc(struct slgt_info *info);
489 static void free_desc(struct slgt_info *info);
490 static int  alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count);
491 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count);
492 
493 static int  alloc_tmp_rbuf(struct slgt_info *info);
494 static void free_tmp_rbuf(struct slgt_info *info);
495 
496 static void tx_timeout(struct timer_list *t);
497 static void rx_timeout(struct timer_list *t);
498 
499 /*
500  * ioctl handlers
501  */
502 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
503 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
504 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
505 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
506 static int  set_txidle(struct slgt_info *info, int idle_mode);
507 static int  tx_enable(struct slgt_info *info, int enable);
508 static int  tx_abort(struct slgt_info *info);
509 static int  rx_enable(struct slgt_info *info, int enable);
510 static int  modem_input_wait(struct slgt_info *info,int arg);
511 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
512 static int  tiocmget(struct tty_struct *tty);
513 static int  tiocmset(struct tty_struct *tty,
514 				unsigned int set, unsigned int clear);
515 static int set_break(struct tty_struct *tty, int break_state);
516 static int  get_interface(struct slgt_info *info, int __user *if_mode);
517 static int  set_interface(struct slgt_info *info, int if_mode);
518 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
519 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
520 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
521 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
522 static int  set_xsync(struct slgt_info *info, int if_mode);
523 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
524 static int  set_xctrl(struct slgt_info *info, int if_mode);
525 
526 /*
527  * driver functions
528  */
529 static void add_device(struct slgt_info *info);
530 static void device_init(int adapter_num, struct pci_dev *pdev);
531 static int  claim_resources(struct slgt_info *info);
532 static void release_resources(struct slgt_info *info);
533 
534 /*
535  * DEBUG OUTPUT CODE
536  */
537 #ifndef DBGINFO
538 #define DBGINFO(fmt)
539 #endif
540 #ifndef DBGERR
541 #define DBGERR(fmt)
542 #endif
543 #ifndef DBGBH
544 #define DBGBH(fmt)
545 #endif
546 #ifndef DBGISR
547 #define DBGISR(fmt)
548 #endif
549 
550 #ifdef DBGDATA
551 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
552 {
553 	int i;
554 	int linecount;
555 	printk("%s %s data:\n",info->device_name, label);
556 	while(count) {
557 		linecount = (count > 16) ? 16 : count;
558 		for(i=0; i < linecount; i++)
559 			printk("%02X ",(unsigned char)data[i]);
560 		for(;i<17;i++)
561 			printk("   ");
562 		for(i=0;i<linecount;i++) {
563 			if (data[i]>=040 && data[i]<=0176)
564 				printk("%c",data[i]);
565 			else
566 				printk(".");
567 		}
568 		printk("\n");
569 		data  += linecount;
570 		count -= linecount;
571 	}
572 }
573 #else
574 #define DBGDATA(info, buf, size, label)
575 #endif
576 
577 #ifdef DBGTBUF
578 static void dump_tbufs(struct slgt_info *info)
579 {
580 	int i;
581 	printk("tbuf_current=%d\n", info->tbuf_current);
582 	for (i=0 ; i < info->tbuf_count ; i++) {
583 		printk("%d: count=%04X status=%04X\n",
584 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
585 	}
586 }
587 #else
588 #define DBGTBUF(info)
589 #endif
590 
591 #ifdef DBGRBUF
592 static void dump_rbufs(struct slgt_info *info)
593 {
594 	int i;
595 	printk("rbuf_current=%d\n", info->rbuf_current);
596 	for (i=0 ; i < info->rbuf_count ; i++) {
597 		printk("%d: count=%04X status=%04X\n",
598 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
599 	}
600 }
601 #else
602 #define DBGRBUF(info)
603 #endif
604 
605 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
606 {
607 #ifdef SANITY_CHECK
608 	if (!info) {
609 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
610 		return 1;
611 	}
612 	if (info->magic != MGSL_MAGIC) {
613 		printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
614 		return 1;
615 	}
616 #else
617 	if (!info)
618 		return 1;
619 #endif
620 	return 0;
621 }
622 
623 /*
624  * line discipline callback wrappers
625  *
626  * The wrappers maintain line discipline references
627  * while calling into the line discipline.
628  *
629  * ldisc_receive_buf  - pass receive data to line discipline
630  */
631 static void ldisc_receive_buf(struct tty_struct *tty,
632 			      const __u8 *data, char *flags, int count)
633 {
634 	struct tty_ldisc *ld;
635 	if (!tty)
636 		return;
637 	ld = tty_ldisc_ref(tty);
638 	if (ld) {
639 		if (ld->ops->receive_buf)
640 			ld->ops->receive_buf(tty, data, flags, count);
641 		tty_ldisc_deref(ld);
642 	}
643 }
644 
645 /* tty callbacks */
646 
647 static int open(struct tty_struct *tty, struct file *filp)
648 {
649 	struct slgt_info *info;
650 	int retval, line;
651 	unsigned long flags;
652 
653 	line = tty->index;
654 	if (line >= slgt_device_count) {
655 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
656 		return -ENODEV;
657 	}
658 
659 	info = slgt_device_list;
660 	while(info && info->line != line)
661 		info = info->next_device;
662 	if (sanity_check(info, tty->name, "open"))
663 		return -ENODEV;
664 	if (info->init_error) {
665 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
666 		return -ENODEV;
667 	}
668 
669 	tty->driver_data = info;
670 	info->port.tty = tty;
671 
672 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
673 
674 	mutex_lock(&info->port.mutex);
675 	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
676 
677 	spin_lock_irqsave(&info->netlock, flags);
678 	if (info->netcount) {
679 		retval = -EBUSY;
680 		spin_unlock_irqrestore(&info->netlock, flags);
681 		mutex_unlock(&info->port.mutex);
682 		goto cleanup;
683 	}
684 	info->port.count++;
685 	spin_unlock_irqrestore(&info->netlock, flags);
686 
687 	if (info->port.count == 1) {
688 		/* 1st open on this device, init hardware */
689 		retval = startup(info);
690 		if (retval < 0) {
691 			mutex_unlock(&info->port.mutex);
692 			goto cleanup;
693 		}
694 	}
695 	mutex_unlock(&info->port.mutex);
696 	retval = block_til_ready(tty, filp, info);
697 	if (retval) {
698 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
699 		goto cleanup;
700 	}
701 
702 	retval = 0;
703 
704 cleanup:
705 	if (retval) {
706 		if (tty->count == 1)
707 			info->port.tty = NULL; /* tty layer will release tty struct */
708 		if(info->port.count)
709 			info->port.count--;
710 	}
711 
712 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
713 	return retval;
714 }
715 
716 static void close(struct tty_struct *tty, struct file *filp)
717 {
718 	struct slgt_info *info = tty->driver_data;
719 
720 	if (sanity_check(info, tty->name, "close"))
721 		return;
722 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
723 
724 	if (tty_port_close_start(&info->port, tty, filp) == 0)
725 		goto cleanup;
726 
727 	mutex_lock(&info->port.mutex);
728 	if (tty_port_initialized(&info->port))
729  		wait_until_sent(tty, info->timeout);
730 	flush_buffer(tty);
731 	tty_ldisc_flush(tty);
732 
733 	shutdown(info);
734 	mutex_unlock(&info->port.mutex);
735 
736 	tty_port_close_end(&info->port, tty);
737 	info->port.tty = NULL;
738 cleanup:
739 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
740 }
741 
742 static void hangup(struct tty_struct *tty)
743 {
744 	struct slgt_info *info = tty->driver_data;
745 	unsigned long flags;
746 
747 	if (sanity_check(info, tty->name, "hangup"))
748 		return;
749 	DBGINFO(("%s hangup\n", info->device_name));
750 
751 	flush_buffer(tty);
752 
753 	mutex_lock(&info->port.mutex);
754 	shutdown(info);
755 
756 	spin_lock_irqsave(&info->port.lock, flags);
757 	info->port.count = 0;
758 	info->port.tty = NULL;
759 	spin_unlock_irqrestore(&info->port.lock, flags);
760 	tty_port_set_active(&info->port, 0);
761 	mutex_unlock(&info->port.mutex);
762 
763 	wake_up_interruptible(&info->port.open_wait);
764 }
765 
766 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
767 {
768 	struct slgt_info *info = tty->driver_data;
769 	unsigned long flags;
770 
771 	DBGINFO(("%s set_termios\n", tty->driver->name));
772 
773 	change_params(info);
774 
775 	/* Handle transition to B0 status */
776 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
777 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
778 		spin_lock_irqsave(&info->lock,flags);
779 		set_signals(info);
780 		spin_unlock_irqrestore(&info->lock,flags);
781 	}
782 
783 	/* Handle transition away from B0 status */
784 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
785 		info->signals |= SerialSignal_DTR;
786 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
787 			info->signals |= SerialSignal_RTS;
788 		spin_lock_irqsave(&info->lock,flags);
789 	 	set_signals(info);
790 		spin_unlock_irqrestore(&info->lock,flags);
791 	}
792 
793 	/* Handle turning off CRTSCTS */
794 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
795 		tty->hw_stopped = 0;
796 		tx_release(tty);
797 	}
798 }
799 
800 static void update_tx_timer(struct slgt_info *info)
801 {
802 	/*
803 	 * use worst case speed of 1200bps to calculate transmit timeout
804 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
805 	 */
806 	if (info->params.mode == MGSL_MODE_HDLC) {
807 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
808 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
809 	}
810 }
811 
812 static int write(struct tty_struct *tty,
813 		 const unsigned char *buf, int count)
814 {
815 	int ret = 0;
816 	struct slgt_info *info = tty->driver_data;
817 	unsigned long flags;
818 
819 	if (sanity_check(info, tty->name, "write"))
820 		return -EIO;
821 
822 	DBGINFO(("%s write count=%d\n", info->device_name, count));
823 
824 	if (!info->tx_buf || (count > info->max_frame_size))
825 		return -EIO;
826 
827 	if (!count || tty->stopped || tty->hw_stopped)
828 		return 0;
829 
830 	spin_lock_irqsave(&info->lock, flags);
831 
832 	if (info->tx_count) {
833 		/* send accumulated data from send_char() */
834 		if (!tx_load(info, info->tx_buf, info->tx_count))
835 			goto cleanup;
836 		info->tx_count = 0;
837 	}
838 
839 	if (tx_load(info, buf, count))
840 		ret = count;
841 
842 cleanup:
843 	spin_unlock_irqrestore(&info->lock, flags);
844 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
845 	return ret;
846 }
847 
848 static int put_char(struct tty_struct *tty, unsigned char ch)
849 {
850 	struct slgt_info *info = tty->driver_data;
851 	unsigned long flags;
852 	int ret = 0;
853 
854 	if (sanity_check(info, tty->name, "put_char"))
855 		return 0;
856 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
857 	if (!info->tx_buf)
858 		return 0;
859 	spin_lock_irqsave(&info->lock,flags);
860 	if (info->tx_count < info->max_frame_size) {
861 		info->tx_buf[info->tx_count++] = ch;
862 		ret = 1;
863 	}
864 	spin_unlock_irqrestore(&info->lock,flags);
865 	return ret;
866 }
867 
868 static void send_xchar(struct tty_struct *tty, char ch)
869 {
870 	struct slgt_info *info = tty->driver_data;
871 	unsigned long flags;
872 
873 	if (sanity_check(info, tty->name, "send_xchar"))
874 		return;
875 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
876 	info->x_char = ch;
877 	if (ch) {
878 		spin_lock_irqsave(&info->lock,flags);
879 		if (!info->tx_enabled)
880 		 	tx_start(info);
881 		spin_unlock_irqrestore(&info->lock,flags);
882 	}
883 }
884 
885 static void wait_until_sent(struct tty_struct *tty, int timeout)
886 {
887 	struct slgt_info *info = tty->driver_data;
888 	unsigned long orig_jiffies, char_time;
889 
890 	if (!info )
891 		return;
892 	if (sanity_check(info, tty->name, "wait_until_sent"))
893 		return;
894 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
895 	if (!tty_port_initialized(&info->port))
896 		goto exit;
897 
898 	orig_jiffies = jiffies;
899 
900 	/* Set check interval to 1/5 of estimated time to
901 	 * send a character, and make it at least 1. The check
902 	 * interval should also be less than the timeout.
903 	 * Note: use tight timings here to satisfy the NIST-PCTS.
904 	 */
905 
906 	if (info->params.data_rate) {
907 	       	char_time = info->timeout/(32 * 5);
908 		if (!char_time)
909 			char_time++;
910 	} else
911 		char_time = 1;
912 
913 	if (timeout)
914 		char_time = min_t(unsigned long, char_time, timeout);
915 
916 	while (info->tx_active) {
917 		msleep_interruptible(jiffies_to_msecs(char_time));
918 		if (signal_pending(current))
919 			break;
920 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
921 			break;
922 	}
923 exit:
924 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
925 }
926 
927 static int write_room(struct tty_struct *tty)
928 {
929 	struct slgt_info *info = tty->driver_data;
930 	int ret;
931 
932 	if (sanity_check(info, tty->name, "write_room"))
933 		return 0;
934 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
935 	DBGINFO(("%s write_room=%d\n", info->device_name, ret));
936 	return ret;
937 }
938 
939 static void flush_chars(struct tty_struct *tty)
940 {
941 	struct slgt_info *info = tty->driver_data;
942 	unsigned long flags;
943 
944 	if (sanity_check(info, tty->name, "flush_chars"))
945 		return;
946 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
947 
948 	if (info->tx_count <= 0 || tty->stopped ||
949 	    tty->hw_stopped || !info->tx_buf)
950 		return;
951 
952 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
953 
954 	spin_lock_irqsave(&info->lock,flags);
955 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
956 		info->tx_count = 0;
957 	spin_unlock_irqrestore(&info->lock,flags);
958 }
959 
960 static void flush_buffer(struct tty_struct *tty)
961 {
962 	struct slgt_info *info = tty->driver_data;
963 	unsigned long flags;
964 
965 	if (sanity_check(info, tty->name, "flush_buffer"))
966 		return;
967 	DBGINFO(("%s flush_buffer\n", info->device_name));
968 
969 	spin_lock_irqsave(&info->lock, flags);
970 	info->tx_count = 0;
971 	spin_unlock_irqrestore(&info->lock, flags);
972 
973 	tty_wakeup(tty);
974 }
975 
976 /*
977  * throttle (stop) transmitter
978  */
979 static void tx_hold(struct tty_struct *tty)
980 {
981 	struct slgt_info *info = tty->driver_data;
982 	unsigned long flags;
983 
984 	if (sanity_check(info, tty->name, "tx_hold"))
985 		return;
986 	DBGINFO(("%s tx_hold\n", info->device_name));
987 	spin_lock_irqsave(&info->lock,flags);
988 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
989 	 	tx_stop(info);
990 	spin_unlock_irqrestore(&info->lock,flags);
991 }
992 
993 /*
994  * release (start) transmitter
995  */
996 static void tx_release(struct tty_struct *tty)
997 {
998 	struct slgt_info *info = tty->driver_data;
999 	unsigned long flags;
1000 
1001 	if (sanity_check(info, tty->name, "tx_release"))
1002 		return;
1003 	DBGINFO(("%s tx_release\n", info->device_name));
1004 	spin_lock_irqsave(&info->lock, flags);
1005 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
1006 		info->tx_count = 0;
1007 	spin_unlock_irqrestore(&info->lock, flags);
1008 }
1009 
1010 /*
1011  * Service an IOCTL request
1012  *
1013  * Arguments
1014  *
1015  * 	tty	pointer to tty instance data
1016  * 	cmd	IOCTL command code
1017  * 	arg	command argument/context
1018  *
1019  * Return 0 if success, otherwise error code
1020  */
1021 static int ioctl(struct tty_struct *tty,
1022 		 unsigned int cmd, unsigned long arg)
1023 {
1024 	struct slgt_info *info = tty->driver_data;
1025 	void __user *argp = (void __user *)arg;
1026 	int ret;
1027 
1028 	if (sanity_check(info, tty->name, "ioctl"))
1029 		return -ENODEV;
1030 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
1031 
1032 	if (cmd != TIOCMIWAIT) {
1033 		if (tty_io_error(tty))
1034 		    return -EIO;
1035 	}
1036 
1037 	switch (cmd) {
1038 	case MGSL_IOCWAITEVENT:
1039 		return wait_mgsl_event(info, argp);
1040 	case TIOCMIWAIT:
1041 		return modem_input_wait(info,(int)arg);
1042 	case MGSL_IOCSGPIO:
1043 		return set_gpio(info, argp);
1044 	case MGSL_IOCGGPIO:
1045 		return get_gpio(info, argp);
1046 	case MGSL_IOCWAITGPIO:
1047 		return wait_gpio(info, argp);
1048 	case MGSL_IOCGXSYNC:
1049 		return get_xsync(info, argp);
1050 	case MGSL_IOCSXSYNC:
1051 		return set_xsync(info, (int)arg);
1052 	case MGSL_IOCGXCTRL:
1053 		return get_xctrl(info, argp);
1054 	case MGSL_IOCSXCTRL:
1055 		return set_xctrl(info, (int)arg);
1056 	}
1057 	mutex_lock(&info->port.mutex);
1058 	switch (cmd) {
1059 	case MGSL_IOCGPARAMS:
1060 		ret = get_params(info, argp);
1061 		break;
1062 	case MGSL_IOCSPARAMS:
1063 		ret = set_params(info, argp);
1064 		break;
1065 	case MGSL_IOCGTXIDLE:
1066 		ret = get_txidle(info, argp);
1067 		break;
1068 	case MGSL_IOCSTXIDLE:
1069 		ret = set_txidle(info, (int)arg);
1070 		break;
1071 	case MGSL_IOCTXENABLE:
1072 		ret = tx_enable(info, (int)arg);
1073 		break;
1074 	case MGSL_IOCRXENABLE:
1075 		ret = rx_enable(info, (int)arg);
1076 		break;
1077 	case MGSL_IOCTXABORT:
1078 		ret = tx_abort(info);
1079 		break;
1080 	case MGSL_IOCGSTATS:
1081 		ret = get_stats(info, argp);
1082 		break;
1083 	case MGSL_IOCGIF:
1084 		ret = get_interface(info, argp);
1085 		break;
1086 	case MGSL_IOCSIF:
1087 		ret = set_interface(info,(int)arg);
1088 		break;
1089 	default:
1090 		ret = -ENOIOCTLCMD;
1091 	}
1092 	mutex_unlock(&info->port.mutex);
1093 	return ret;
1094 }
1095 
1096 static int get_icount(struct tty_struct *tty,
1097 				struct serial_icounter_struct *icount)
1098 
1099 {
1100 	struct slgt_info *info = tty->driver_data;
1101 	struct mgsl_icount cnow;	/* kernel counter temps */
1102 	unsigned long flags;
1103 
1104 	spin_lock_irqsave(&info->lock,flags);
1105 	cnow = info->icount;
1106 	spin_unlock_irqrestore(&info->lock,flags);
1107 
1108 	icount->cts = cnow.cts;
1109 	icount->dsr = cnow.dsr;
1110 	icount->rng = cnow.rng;
1111 	icount->dcd = cnow.dcd;
1112 	icount->rx = cnow.rx;
1113 	icount->tx = cnow.tx;
1114 	icount->frame = cnow.frame;
1115 	icount->overrun = cnow.overrun;
1116 	icount->parity = cnow.parity;
1117 	icount->brk = cnow.brk;
1118 	icount->buf_overrun = cnow.buf_overrun;
1119 
1120 	return 0;
1121 }
1122 
1123 /*
1124  * support for 32 bit ioctl calls on 64 bit systems
1125  */
1126 #ifdef CONFIG_COMPAT
1127 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1128 {
1129 	struct MGSL_PARAMS32 tmp_params;
1130 
1131 	DBGINFO(("%s get_params32\n", info->device_name));
1132 	memset(&tmp_params, 0, sizeof(tmp_params));
1133 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1134 	tmp_params.loopback        = info->params.loopback;
1135 	tmp_params.flags           = info->params.flags;
1136 	tmp_params.encoding        = info->params.encoding;
1137 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1138 	tmp_params.addr_filter     = info->params.addr_filter;
1139 	tmp_params.crc_type        = info->params.crc_type;
1140 	tmp_params.preamble_length = info->params.preamble_length;
1141 	tmp_params.preamble        = info->params.preamble;
1142 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1143 	tmp_params.data_bits       = info->params.data_bits;
1144 	tmp_params.stop_bits       = info->params.stop_bits;
1145 	tmp_params.parity          = info->params.parity;
1146 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1147 		return -EFAULT;
1148 	return 0;
1149 }
1150 
1151 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1152 {
1153 	struct MGSL_PARAMS32 tmp_params;
1154 
1155 	DBGINFO(("%s set_params32\n", info->device_name));
1156 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1157 		return -EFAULT;
1158 
1159 	spin_lock(&info->lock);
1160 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1161 		info->base_clock = tmp_params.clock_speed;
1162 	} else {
1163 		info->params.mode            = tmp_params.mode;
1164 		info->params.loopback        = tmp_params.loopback;
1165 		info->params.flags           = tmp_params.flags;
1166 		info->params.encoding        = tmp_params.encoding;
1167 		info->params.clock_speed     = tmp_params.clock_speed;
1168 		info->params.addr_filter     = tmp_params.addr_filter;
1169 		info->params.crc_type        = tmp_params.crc_type;
1170 		info->params.preamble_length = tmp_params.preamble_length;
1171 		info->params.preamble        = tmp_params.preamble;
1172 		info->params.data_rate       = tmp_params.data_rate;
1173 		info->params.data_bits       = tmp_params.data_bits;
1174 		info->params.stop_bits       = tmp_params.stop_bits;
1175 		info->params.parity          = tmp_params.parity;
1176 	}
1177 	spin_unlock(&info->lock);
1178 
1179 	program_hw(info);
1180 
1181 	return 0;
1182 }
1183 
1184 static long slgt_compat_ioctl(struct tty_struct *tty,
1185 			 unsigned int cmd, unsigned long arg)
1186 {
1187 	struct slgt_info *info = tty->driver_data;
1188 	int rc;
1189 
1190 	if (sanity_check(info, tty->name, "compat_ioctl"))
1191 		return -ENODEV;
1192 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1193 
1194 	switch (cmd) {
1195 	case MGSL_IOCSPARAMS32:
1196 		rc = set_params32(info, compat_ptr(arg));
1197 		break;
1198 
1199 	case MGSL_IOCGPARAMS32:
1200 		rc = get_params32(info, compat_ptr(arg));
1201 		break;
1202 
1203 	case MGSL_IOCGPARAMS:
1204 	case MGSL_IOCSPARAMS:
1205 	case MGSL_IOCGTXIDLE:
1206 	case MGSL_IOCGSTATS:
1207 	case MGSL_IOCWAITEVENT:
1208 	case MGSL_IOCGIF:
1209 	case MGSL_IOCSGPIO:
1210 	case MGSL_IOCGGPIO:
1211 	case MGSL_IOCWAITGPIO:
1212 	case MGSL_IOCGXSYNC:
1213 	case MGSL_IOCGXCTRL:
1214 		rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1215 		break;
1216 	default:
1217 		rc = ioctl(tty, cmd, arg);
1218 	}
1219 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1220 	return rc;
1221 }
1222 #else
1223 #define slgt_compat_ioctl NULL
1224 #endif /* ifdef CONFIG_COMPAT */
1225 
1226 /*
1227  * proc fs support
1228  */
1229 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1230 {
1231 	char stat_buf[30];
1232 	unsigned long flags;
1233 
1234 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1235 		      info->device_name, info->phys_reg_addr,
1236 		      info->irq_level, info->max_frame_size);
1237 
1238 	/* output current serial signal states */
1239 	spin_lock_irqsave(&info->lock,flags);
1240 	get_signals(info);
1241 	spin_unlock_irqrestore(&info->lock,flags);
1242 
1243 	stat_buf[0] = 0;
1244 	stat_buf[1] = 0;
1245 	if (info->signals & SerialSignal_RTS)
1246 		strcat(stat_buf, "|RTS");
1247 	if (info->signals & SerialSignal_CTS)
1248 		strcat(stat_buf, "|CTS");
1249 	if (info->signals & SerialSignal_DTR)
1250 		strcat(stat_buf, "|DTR");
1251 	if (info->signals & SerialSignal_DSR)
1252 		strcat(stat_buf, "|DSR");
1253 	if (info->signals & SerialSignal_DCD)
1254 		strcat(stat_buf, "|CD");
1255 	if (info->signals & SerialSignal_RI)
1256 		strcat(stat_buf, "|RI");
1257 
1258 	if (info->params.mode != MGSL_MODE_ASYNC) {
1259 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1260 			       info->icount.txok, info->icount.rxok);
1261 		if (info->icount.txunder)
1262 			seq_printf(m, " txunder:%d", info->icount.txunder);
1263 		if (info->icount.txabort)
1264 			seq_printf(m, " txabort:%d", info->icount.txabort);
1265 		if (info->icount.rxshort)
1266 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1267 		if (info->icount.rxlong)
1268 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1269 		if (info->icount.rxover)
1270 			seq_printf(m, " rxover:%d", info->icount.rxover);
1271 		if (info->icount.rxcrc)
1272 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1273 	} else {
1274 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1275 			       info->icount.tx, info->icount.rx);
1276 		if (info->icount.frame)
1277 			seq_printf(m, " fe:%d", info->icount.frame);
1278 		if (info->icount.parity)
1279 			seq_printf(m, " pe:%d", info->icount.parity);
1280 		if (info->icount.brk)
1281 			seq_printf(m, " brk:%d", info->icount.brk);
1282 		if (info->icount.overrun)
1283 			seq_printf(m, " oe:%d", info->icount.overrun);
1284 	}
1285 
1286 	/* Append serial signal status to end */
1287 	seq_printf(m, " %s\n", stat_buf+1);
1288 
1289 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1290 		       info->tx_active,info->bh_requested,info->bh_running,
1291 		       info->pending_bh);
1292 }
1293 
1294 /* Called to print information about devices
1295  */
1296 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1297 {
1298 	struct slgt_info *info;
1299 
1300 	seq_puts(m, "synclink_gt driver\n");
1301 
1302 	info = slgt_device_list;
1303 	while( info ) {
1304 		line_info(m, info);
1305 		info = info->next_device;
1306 	}
1307 	return 0;
1308 }
1309 
1310 /*
1311  * return count of bytes in transmit buffer
1312  */
1313 static int chars_in_buffer(struct tty_struct *tty)
1314 {
1315 	struct slgt_info *info = tty->driver_data;
1316 	int count;
1317 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1318 		return 0;
1319 	count = tbuf_bytes(info);
1320 	DBGINFO(("%s chars_in_buffer()=%d\n", info->device_name, count));
1321 	return count;
1322 }
1323 
1324 /*
1325  * signal remote device to throttle send data (our receive data)
1326  */
1327 static void throttle(struct tty_struct * tty)
1328 {
1329 	struct slgt_info *info = tty->driver_data;
1330 	unsigned long flags;
1331 
1332 	if (sanity_check(info, tty->name, "throttle"))
1333 		return;
1334 	DBGINFO(("%s throttle\n", info->device_name));
1335 	if (I_IXOFF(tty))
1336 		send_xchar(tty, STOP_CHAR(tty));
1337 	if (C_CRTSCTS(tty)) {
1338 		spin_lock_irqsave(&info->lock,flags);
1339 		info->signals &= ~SerialSignal_RTS;
1340 		set_signals(info);
1341 		spin_unlock_irqrestore(&info->lock,flags);
1342 	}
1343 }
1344 
1345 /*
1346  * signal remote device to stop throttling send data (our receive data)
1347  */
1348 static void unthrottle(struct tty_struct * tty)
1349 {
1350 	struct slgt_info *info = tty->driver_data;
1351 	unsigned long flags;
1352 
1353 	if (sanity_check(info, tty->name, "unthrottle"))
1354 		return;
1355 	DBGINFO(("%s unthrottle\n", info->device_name));
1356 	if (I_IXOFF(tty)) {
1357 		if (info->x_char)
1358 			info->x_char = 0;
1359 		else
1360 			send_xchar(tty, START_CHAR(tty));
1361 	}
1362 	if (C_CRTSCTS(tty)) {
1363 		spin_lock_irqsave(&info->lock,flags);
1364 		info->signals |= SerialSignal_RTS;
1365 		set_signals(info);
1366 		spin_unlock_irqrestore(&info->lock,flags);
1367 	}
1368 }
1369 
1370 /*
1371  * set or clear transmit break condition
1372  * break_state	-1=set break condition, 0=clear
1373  */
1374 static int set_break(struct tty_struct *tty, int break_state)
1375 {
1376 	struct slgt_info *info = tty->driver_data;
1377 	unsigned short value;
1378 	unsigned long flags;
1379 
1380 	if (sanity_check(info, tty->name, "set_break"))
1381 		return -EINVAL;
1382 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1383 
1384 	spin_lock_irqsave(&info->lock,flags);
1385 	value = rd_reg16(info, TCR);
1386  	if (break_state == -1)
1387 		value |= BIT6;
1388 	else
1389 		value &= ~BIT6;
1390 	wr_reg16(info, TCR, value);
1391 	spin_unlock_irqrestore(&info->lock,flags);
1392 	return 0;
1393 }
1394 
1395 #if SYNCLINK_GENERIC_HDLC
1396 
1397 /**
1398  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1399  * @dev:      pointer to network device structure
1400  * @encoding: serial encoding setting
1401  * @parity:   FCS setting
1402  *
1403  * Set encoding and frame check sequence (FCS) options.
1404  *
1405  * Return: 0 if success, otherwise error code
1406  */
1407 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1408 			  unsigned short parity)
1409 {
1410 	struct slgt_info *info = dev_to_port(dev);
1411 	unsigned char  new_encoding;
1412 	unsigned short new_crctype;
1413 
1414 	/* return error if TTY interface open */
1415 	if (info->port.count)
1416 		return -EBUSY;
1417 
1418 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1419 
1420 	switch (encoding)
1421 	{
1422 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1423 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1424 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1425 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1426 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1427 	default: return -EINVAL;
1428 	}
1429 
1430 	switch (parity)
1431 	{
1432 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1433 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1434 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1435 	default: return -EINVAL;
1436 	}
1437 
1438 	info->params.encoding = new_encoding;
1439 	info->params.crc_type = new_crctype;
1440 
1441 	/* if network interface up, reprogram hardware */
1442 	if (info->netcount)
1443 		program_hw(info);
1444 
1445 	return 0;
1446 }
1447 
1448 /**
1449  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1450  * @skb: socket buffer containing HDLC frame
1451  * @dev: pointer to network device structure
1452  */
1453 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1454 				      struct net_device *dev)
1455 {
1456 	struct slgt_info *info = dev_to_port(dev);
1457 	unsigned long flags;
1458 
1459 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1460 
1461 	if (!skb->len)
1462 		return NETDEV_TX_OK;
1463 
1464 	/* stop sending until this frame completes */
1465 	netif_stop_queue(dev);
1466 
1467 	/* update network statistics */
1468 	dev->stats.tx_packets++;
1469 	dev->stats.tx_bytes += skb->len;
1470 
1471 	/* save start time for transmit timeout detection */
1472 	netif_trans_update(dev);
1473 
1474 	spin_lock_irqsave(&info->lock, flags);
1475 	tx_load(info, skb->data, skb->len);
1476 	spin_unlock_irqrestore(&info->lock, flags);
1477 
1478 	/* done with socket buffer, so free it */
1479 	dev_kfree_skb(skb);
1480 
1481 	return NETDEV_TX_OK;
1482 }
1483 
1484 /**
1485  * hdlcdev_open - called by network layer when interface enabled
1486  * @dev: pointer to network device structure
1487  *
1488  * Claim resources and initialize hardware.
1489  *
1490  * Return: 0 if success, otherwise error code
1491  */
1492 static int hdlcdev_open(struct net_device *dev)
1493 {
1494 	struct slgt_info *info = dev_to_port(dev);
1495 	int rc;
1496 	unsigned long flags;
1497 
1498 	if (!try_module_get(THIS_MODULE))
1499 		return -EBUSY;
1500 
1501 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1502 
1503 	/* generic HDLC layer open processing */
1504 	rc = hdlc_open(dev);
1505 	if (rc)
1506 		return rc;
1507 
1508 	/* arbitrate between network and tty opens */
1509 	spin_lock_irqsave(&info->netlock, flags);
1510 	if (info->port.count != 0 || info->netcount != 0) {
1511 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1512 		spin_unlock_irqrestore(&info->netlock, flags);
1513 		return -EBUSY;
1514 	}
1515 	info->netcount=1;
1516 	spin_unlock_irqrestore(&info->netlock, flags);
1517 
1518 	/* claim resources and init adapter */
1519 	if ((rc = startup(info)) != 0) {
1520 		spin_lock_irqsave(&info->netlock, flags);
1521 		info->netcount=0;
1522 		spin_unlock_irqrestore(&info->netlock, flags);
1523 		return rc;
1524 	}
1525 
1526 	/* assert RTS and DTR, apply hardware settings */
1527 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1528 	program_hw(info);
1529 
1530 	/* enable network layer transmit */
1531 	netif_trans_update(dev);
1532 	netif_start_queue(dev);
1533 
1534 	/* inform generic HDLC layer of current DCD status */
1535 	spin_lock_irqsave(&info->lock, flags);
1536 	get_signals(info);
1537 	spin_unlock_irqrestore(&info->lock, flags);
1538 	if (info->signals & SerialSignal_DCD)
1539 		netif_carrier_on(dev);
1540 	else
1541 		netif_carrier_off(dev);
1542 	return 0;
1543 }
1544 
1545 /**
1546  * hdlcdev_close - called by network layer when interface is disabled
1547  * @dev:  pointer to network device structure
1548  *
1549  * Shutdown hardware and release resources.
1550  *
1551  * Return: 0 if success, otherwise error code
1552  */
1553 static int hdlcdev_close(struct net_device *dev)
1554 {
1555 	struct slgt_info *info = dev_to_port(dev);
1556 	unsigned long flags;
1557 
1558 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1559 
1560 	netif_stop_queue(dev);
1561 
1562 	/* shutdown adapter and release resources */
1563 	shutdown(info);
1564 
1565 	hdlc_close(dev);
1566 
1567 	spin_lock_irqsave(&info->netlock, flags);
1568 	info->netcount=0;
1569 	spin_unlock_irqrestore(&info->netlock, flags);
1570 
1571 	module_put(THIS_MODULE);
1572 	return 0;
1573 }
1574 
1575 /**
1576  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1577  * @dev: pointer to network device structure
1578  * @ifr: pointer to network interface request structure
1579  * @cmd: IOCTL command code
1580  *
1581  * Return: 0 if success, otherwise error code
1582  */
1583 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1584 {
1585 	const size_t size = sizeof(sync_serial_settings);
1586 	sync_serial_settings new_line;
1587 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1588 	struct slgt_info *info = dev_to_port(dev);
1589 	unsigned int flags;
1590 
1591 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1592 
1593 	/* return error if TTY interface open */
1594 	if (info->port.count)
1595 		return -EBUSY;
1596 
1597 	if (cmd != SIOCWANDEV)
1598 		return hdlc_ioctl(dev, ifr, cmd);
1599 
1600 	memset(&new_line, 0, sizeof(new_line));
1601 
1602 	switch(ifr->ifr_settings.type) {
1603 	case IF_GET_IFACE: /* return current sync_serial_settings */
1604 
1605 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1606 		if (ifr->ifr_settings.size < size) {
1607 			ifr->ifr_settings.size = size; /* data size wanted */
1608 			return -ENOBUFS;
1609 		}
1610 
1611 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1612 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1613 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1614 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1615 
1616 		switch (flags){
1617 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1618 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1619 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1620 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1621 		default: new_line.clock_type = CLOCK_DEFAULT;
1622 		}
1623 
1624 		new_line.clock_rate = info->params.clock_speed;
1625 		new_line.loopback   = info->params.loopback ? 1:0;
1626 
1627 		if (copy_to_user(line, &new_line, size))
1628 			return -EFAULT;
1629 		return 0;
1630 
1631 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1632 
1633 		if(!capable(CAP_NET_ADMIN))
1634 			return -EPERM;
1635 		if (copy_from_user(&new_line, line, size))
1636 			return -EFAULT;
1637 
1638 		switch (new_line.clock_type)
1639 		{
1640 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1641 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1642 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1643 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1644 		case CLOCK_DEFAULT:  flags = info->params.flags &
1645 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1646 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1647 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1648 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1649 		default: return -EINVAL;
1650 		}
1651 
1652 		if (new_line.loopback != 0 && new_line.loopback != 1)
1653 			return -EINVAL;
1654 
1655 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1656 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1657 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1658 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1659 		info->params.flags |= flags;
1660 
1661 		info->params.loopback = new_line.loopback;
1662 
1663 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1664 			info->params.clock_speed = new_line.clock_rate;
1665 		else
1666 			info->params.clock_speed = 0;
1667 
1668 		/* if network interface up, reprogram hardware */
1669 		if (info->netcount)
1670 			program_hw(info);
1671 		return 0;
1672 
1673 	default:
1674 		return hdlc_ioctl(dev, ifr, cmd);
1675 	}
1676 }
1677 
1678 /**
1679  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1680  * @dev: pointer to network device structure
1681  * @txqueue: unused
1682  */
1683 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1684 {
1685 	struct slgt_info *info = dev_to_port(dev);
1686 	unsigned long flags;
1687 
1688 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1689 
1690 	dev->stats.tx_errors++;
1691 	dev->stats.tx_aborted_errors++;
1692 
1693 	spin_lock_irqsave(&info->lock,flags);
1694 	tx_stop(info);
1695 	spin_unlock_irqrestore(&info->lock,flags);
1696 
1697 	netif_wake_queue(dev);
1698 }
1699 
1700 /**
1701  * hdlcdev_tx_done - called by device driver when transmit completes
1702  * @info: pointer to device instance information
1703  *
1704  * Reenable network layer transmit if stopped.
1705  */
1706 static void hdlcdev_tx_done(struct slgt_info *info)
1707 {
1708 	if (netif_queue_stopped(info->netdev))
1709 		netif_wake_queue(info->netdev);
1710 }
1711 
1712 /**
1713  * hdlcdev_rx - called by device driver when frame received
1714  * @info: pointer to device instance information
1715  * @buf:  pointer to buffer contianing frame data
1716  * @size: count of data bytes in buf
1717  *
1718  * Pass frame to network layer.
1719  */
1720 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1721 {
1722 	struct sk_buff *skb = dev_alloc_skb(size);
1723 	struct net_device *dev = info->netdev;
1724 
1725 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1726 
1727 	if (skb == NULL) {
1728 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1729 		dev->stats.rx_dropped++;
1730 		return;
1731 	}
1732 
1733 	skb_put_data(skb, buf, size);
1734 
1735 	skb->protocol = hdlc_type_trans(skb, dev);
1736 
1737 	dev->stats.rx_packets++;
1738 	dev->stats.rx_bytes += size;
1739 
1740 	netif_rx(skb);
1741 }
1742 
1743 static const struct net_device_ops hdlcdev_ops = {
1744 	.ndo_open       = hdlcdev_open,
1745 	.ndo_stop       = hdlcdev_close,
1746 	.ndo_start_xmit = hdlc_start_xmit,
1747 	.ndo_do_ioctl   = hdlcdev_ioctl,
1748 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1749 };
1750 
1751 /**
1752  * hdlcdev_init - called by device driver when adding device instance
1753  * @info: pointer to device instance information
1754  *
1755  * Do generic HDLC initialization.
1756  *
1757  * Return: 0 if success, otherwise error code
1758  */
1759 static int hdlcdev_init(struct slgt_info *info)
1760 {
1761 	int rc;
1762 	struct net_device *dev;
1763 	hdlc_device *hdlc;
1764 
1765 	/* allocate and initialize network and HDLC layer objects */
1766 
1767 	dev = alloc_hdlcdev(info);
1768 	if (!dev) {
1769 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1770 		return -ENOMEM;
1771 	}
1772 
1773 	/* for network layer reporting purposes only */
1774 	dev->mem_start = info->phys_reg_addr;
1775 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1776 	dev->irq       = info->irq_level;
1777 
1778 	/* network layer callbacks and settings */
1779 	dev->netdev_ops	    = &hdlcdev_ops;
1780 	dev->watchdog_timeo = 10 * HZ;
1781 	dev->tx_queue_len   = 50;
1782 
1783 	/* generic HDLC layer callbacks and settings */
1784 	hdlc         = dev_to_hdlc(dev);
1785 	hdlc->attach = hdlcdev_attach;
1786 	hdlc->xmit   = hdlcdev_xmit;
1787 
1788 	/* register objects with HDLC layer */
1789 	rc = register_hdlc_device(dev);
1790 	if (rc) {
1791 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1792 		free_netdev(dev);
1793 		return rc;
1794 	}
1795 
1796 	info->netdev = dev;
1797 	return 0;
1798 }
1799 
1800 /**
1801  * hdlcdev_exit - called by device driver when removing device instance
1802  * @info: pointer to device instance information
1803  *
1804  * Do generic HDLC cleanup.
1805  */
1806 static void hdlcdev_exit(struct slgt_info *info)
1807 {
1808 	unregister_hdlc_device(info->netdev);
1809 	free_netdev(info->netdev);
1810 	info->netdev = NULL;
1811 }
1812 
1813 #endif /* ifdef CONFIG_HDLC */
1814 
1815 /*
1816  * get async data from rx DMA buffers
1817  */
1818 static void rx_async(struct slgt_info *info)
1819 {
1820  	struct mgsl_icount *icount = &info->icount;
1821 	unsigned int start, end;
1822 	unsigned char *p;
1823 	unsigned char status;
1824 	struct slgt_desc *bufs = info->rbufs;
1825 	int i, count;
1826 	int chars = 0;
1827 	int stat;
1828 	unsigned char ch;
1829 
1830 	start = end = info->rbuf_current;
1831 
1832 	while(desc_complete(bufs[end])) {
1833 		count = desc_count(bufs[end]) - info->rbuf_index;
1834 		p     = bufs[end].buf + info->rbuf_index;
1835 
1836 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1837 		DBGDATA(info, p, count, "rx");
1838 
1839 		for(i=0 ; i < count; i+=2, p+=2) {
1840 			ch = *p;
1841 			icount->rx++;
1842 
1843 			stat = 0;
1844 
1845 			status = *(p + 1) & (BIT1 + BIT0);
1846 			if (status) {
1847 				if (status & BIT1)
1848 					icount->parity++;
1849 				else if (status & BIT0)
1850 					icount->frame++;
1851 				/* discard char if tty control flags say so */
1852 				if (status & info->ignore_status_mask)
1853 					continue;
1854 				if (status & BIT1)
1855 					stat = TTY_PARITY;
1856 				else if (status & BIT0)
1857 					stat = TTY_FRAME;
1858 			}
1859 			tty_insert_flip_char(&info->port, ch, stat);
1860 			chars++;
1861 		}
1862 
1863 		if (i < count) {
1864 			/* receive buffer not completed */
1865 			info->rbuf_index += i;
1866 			mod_timer(&info->rx_timer, jiffies + 1);
1867 			break;
1868 		}
1869 
1870 		info->rbuf_index = 0;
1871 		free_rbufs(info, end, end);
1872 
1873 		if (++end == info->rbuf_count)
1874 			end = 0;
1875 
1876 		/* if entire list searched then no frame available */
1877 		if (end == start)
1878 			break;
1879 	}
1880 
1881 	if (chars)
1882 		tty_flip_buffer_push(&info->port);
1883 }
1884 
1885 /*
1886  * return next bottom half action to perform
1887  */
1888 static int bh_action(struct slgt_info *info)
1889 {
1890 	unsigned long flags;
1891 	int rc;
1892 
1893 	spin_lock_irqsave(&info->lock,flags);
1894 
1895 	if (info->pending_bh & BH_RECEIVE) {
1896 		info->pending_bh &= ~BH_RECEIVE;
1897 		rc = BH_RECEIVE;
1898 	} else if (info->pending_bh & BH_TRANSMIT) {
1899 		info->pending_bh &= ~BH_TRANSMIT;
1900 		rc = BH_TRANSMIT;
1901 	} else if (info->pending_bh & BH_STATUS) {
1902 		info->pending_bh &= ~BH_STATUS;
1903 		rc = BH_STATUS;
1904 	} else {
1905 		/* Mark BH routine as complete */
1906 		info->bh_running = false;
1907 		info->bh_requested = false;
1908 		rc = 0;
1909 	}
1910 
1911 	spin_unlock_irqrestore(&info->lock,flags);
1912 
1913 	return rc;
1914 }
1915 
1916 /*
1917  * perform bottom half processing
1918  */
1919 static void bh_handler(struct work_struct *work)
1920 {
1921 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1922 	int action;
1923 
1924 	info->bh_running = true;
1925 
1926 	while((action = bh_action(info))) {
1927 		switch (action) {
1928 		case BH_RECEIVE:
1929 			DBGBH(("%s bh receive\n", info->device_name));
1930 			switch(info->params.mode) {
1931 			case MGSL_MODE_ASYNC:
1932 				rx_async(info);
1933 				break;
1934 			case MGSL_MODE_HDLC:
1935 				while(rx_get_frame(info));
1936 				break;
1937 			case MGSL_MODE_RAW:
1938 			case MGSL_MODE_MONOSYNC:
1939 			case MGSL_MODE_BISYNC:
1940 			case MGSL_MODE_XSYNC:
1941 				while(rx_get_buf(info));
1942 				break;
1943 			}
1944 			/* restart receiver if rx DMA buffers exhausted */
1945 			if (info->rx_restart)
1946 				rx_start(info);
1947 			break;
1948 		case BH_TRANSMIT:
1949 			bh_transmit(info);
1950 			break;
1951 		case BH_STATUS:
1952 			DBGBH(("%s bh status\n", info->device_name));
1953 			info->ri_chkcount = 0;
1954 			info->dsr_chkcount = 0;
1955 			info->dcd_chkcount = 0;
1956 			info->cts_chkcount = 0;
1957 			break;
1958 		default:
1959 			DBGBH(("%s unknown action\n", info->device_name));
1960 			break;
1961 		}
1962 	}
1963 	DBGBH(("%s bh_handler exit\n", info->device_name));
1964 }
1965 
1966 static void bh_transmit(struct slgt_info *info)
1967 {
1968 	struct tty_struct *tty = info->port.tty;
1969 
1970 	DBGBH(("%s bh_transmit\n", info->device_name));
1971 	if (tty)
1972 		tty_wakeup(tty);
1973 }
1974 
1975 static void dsr_change(struct slgt_info *info, unsigned short status)
1976 {
1977 	if (status & BIT3) {
1978 		info->signals |= SerialSignal_DSR;
1979 		info->input_signal_events.dsr_up++;
1980 	} else {
1981 		info->signals &= ~SerialSignal_DSR;
1982 		info->input_signal_events.dsr_down++;
1983 	}
1984 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1985 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1986 		slgt_irq_off(info, IRQ_DSR);
1987 		return;
1988 	}
1989 	info->icount.dsr++;
1990 	wake_up_interruptible(&info->status_event_wait_q);
1991 	wake_up_interruptible(&info->event_wait_q);
1992 	info->pending_bh |= BH_STATUS;
1993 }
1994 
1995 static void cts_change(struct slgt_info *info, unsigned short status)
1996 {
1997 	if (status & BIT2) {
1998 		info->signals |= SerialSignal_CTS;
1999 		info->input_signal_events.cts_up++;
2000 	} else {
2001 		info->signals &= ~SerialSignal_CTS;
2002 		info->input_signal_events.cts_down++;
2003 	}
2004 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
2005 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2006 		slgt_irq_off(info, IRQ_CTS);
2007 		return;
2008 	}
2009 	info->icount.cts++;
2010 	wake_up_interruptible(&info->status_event_wait_q);
2011 	wake_up_interruptible(&info->event_wait_q);
2012 	info->pending_bh |= BH_STATUS;
2013 
2014 	if (tty_port_cts_enabled(&info->port)) {
2015 		if (info->port.tty) {
2016 			if (info->port.tty->hw_stopped) {
2017 				if (info->signals & SerialSignal_CTS) {
2018 		 			info->port.tty->hw_stopped = 0;
2019 					info->pending_bh |= BH_TRANSMIT;
2020 					return;
2021 				}
2022 			} else {
2023 				if (!(info->signals & SerialSignal_CTS))
2024 		 			info->port.tty->hw_stopped = 1;
2025 			}
2026 		}
2027 	}
2028 }
2029 
2030 static void dcd_change(struct slgt_info *info, unsigned short status)
2031 {
2032 	if (status & BIT1) {
2033 		info->signals |= SerialSignal_DCD;
2034 		info->input_signal_events.dcd_up++;
2035 	} else {
2036 		info->signals &= ~SerialSignal_DCD;
2037 		info->input_signal_events.dcd_down++;
2038 	}
2039 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
2040 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2041 		slgt_irq_off(info, IRQ_DCD);
2042 		return;
2043 	}
2044 	info->icount.dcd++;
2045 #if SYNCLINK_GENERIC_HDLC
2046 	if (info->netcount) {
2047 		if (info->signals & SerialSignal_DCD)
2048 			netif_carrier_on(info->netdev);
2049 		else
2050 			netif_carrier_off(info->netdev);
2051 	}
2052 #endif
2053 	wake_up_interruptible(&info->status_event_wait_q);
2054 	wake_up_interruptible(&info->event_wait_q);
2055 	info->pending_bh |= BH_STATUS;
2056 
2057 	if (tty_port_check_carrier(&info->port)) {
2058 		if (info->signals & SerialSignal_DCD)
2059 			wake_up_interruptible(&info->port.open_wait);
2060 		else {
2061 			if (info->port.tty)
2062 				tty_hangup(info->port.tty);
2063 		}
2064 	}
2065 }
2066 
2067 static void ri_change(struct slgt_info *info, unsigned short status)
2068 {
2069 	if (status & BIT0) {
2070 		info->signals |= SerialSignal_RI;
2071 		info->input_signal_events.ri_up++;
2072 	} else {
2073 		info->signals &= ~SerialSignal_RI;
2074 		info->input_signal_events.ri_down++;
2075 	}
2076 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2077 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2078 		slgt_irq_off(info, IRQ_RI);
2079 		return;
2080 	}
2081 	info->icount.rng++;
2082 	wake_up_interruptible(&info->status_event_wait_q);
2083 	wake_up_interruptible(&info->event_wait_q);
2084 	info->pending_bh |= BH_STATUS;
2085 }
2086 
2087 static void isr_rxdata(struct slgt_info *info)
2088 {
2089 	unsigned int count = info->rbuf_fill_count;
2090 	unsigned int i = info->rbuf_fill_index;
2091 	unsigned short reg;
2092 
2093 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2094 		reg = rd_reg16(info, RDR);
2095 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2096 		if (desc_complete(info->rbufs[i])) {
2097 			/* all buffers full */
2098 			rx_stop(info);
2099 			info->rx_restart = true;
2100 			continue;
2101 		}
2102 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2103 		/* async mode saves status byte to buffer for each data byte */
2104 		if (info->params.mode == MGSL_MODE_ASYNC)
2105 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2106 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2107 			/* buffer full or end of frame */
2108 			set_desc_count(info->rbufs[i], count);
2109 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2110 			info->rbuf_fill_count = count = 0;
2111 			if (++i == info->rbuf_count)
2112 				i = 0;
2113 			info->pending_bh |= BH_RECEIVE;
2114 		}
2115 	}
2116 
2117 	info->rbuf_fill_index = i;
2118 	info->rbuf_fill_count = count;
2119 }
2120 
2121 static void isr_serial(struct slgt_info *info)
2122 {
2123 	unsigned short status = rd_reg16(info, SSR);
2124 
2125 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2126 
2127 	wr_reg16(info, SSR, status); /* clear pending */
2128 
2129 	info->irq_occurred = true;
2130 
2131 	if (info->params.mode == MGSL_MODE_ASYNC) {
2132 		if (status & IRQ_TXIDLE) {
2133 			if (info->tx_active)
2134 				isr_txeom(info, status);
2135 		}
2136 		if (info->rx_pio && (status & IRQ_RXDATA))
2137 			isr_rxdata(info);
2138 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2139 			info->icount.brk++;
2140 			/* process break detection if tty control allows */
2141 			if (info->port.tty) {
2142 				if (!(status & info->ignore_status_mask)) {
2143 					if (info->read_status_mask & MASK_BREAK) {
2144 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2145 						if (info->port.flags & ASYNC_SAK)
2146 							do_SAK(info->port.tty);
2147 					}
2148 				}
2149 			}
2150 		}
2151 	} else {
2152 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2153 			isr_txeom(info, status);
2154 		if (info->rx_pio && (status & IRQ_RXDATA))
2155 			isr_rxdata(info);
2156 		if (status & IRQ_RXIDLE) {
2157 			if (status & RXIDLE)
2158 				info->icount.rxidle++;
2159 			else
2160 				info->icount.exithunt++;
2161 			wake_up_interruptible(&info->event_wait_q);
2162 		}
2163 
2164 		if (status & IRQ_RXOVER)
2165 			rx_start(info);
2166 	}
2167 
2168 	if (status & IRQ_DSR)
2169 		dsr_change(info, status);
2170 	if (status & IRQ_CTS)
2171 		cts_change(info, status);
2172 	if (status & IRQ_DCD)
2173 		dcd_change(info, status);
2174 	if (status & IRQ_RI)
2175 		ri_change(info, status);
2176 }
2177 
2178 static void isr_rdma(struct slgt_info *info)
2179 {
2180 	unsigned int status = rd_reg32(info, RDCSR);
2181 
2182 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2183 
2184 	/* RDCSR (rx DMA control/status)
2185 	 *
2186 	 * 31..07  reserved
2187 	 * 06      save status byte to DMA buffer
2188 	 * 05      error
2189 	 * 04      eol (end of list)
2190 	 * 03      eob (end of buffer)
2191 	 * 02      IRQ enable
2192 	 * 01      reset
2193 	 * 00      enable
2194 	 */
2195 	wr_reg32(info, RDCSR, status);	/* clear pending */
2196 
2197 	if (status & (BIT5 + BIT4)) {
2198 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2199 		info->rx_restart = true;
2200 	}
2201 	info->pending_bh |= BH_RECEIVE;
2202 }
2203 
2204 static void isr_tdma(struct slgt_info *info)
2205 {
2206 	unsigned int status = rd_reg32(info, TDCSR);
2207 
2208 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2209 
2210 	/* TDCSR (tx DMA control/status)
2211 	 *
2212 	 * 31..06  reserved
2213 	 * 05      error
2214 	 * 04      eol (end of list)
2215 	 * 03      eob (end of buffer)
2216 	 * 02      IRQ enable
2217 	 * 01      reset
2218 	 * 00      enable
2219 	 */
2220 	wr_reg32(info, TDCSR, status);	/* clear pending */
2221 
2222 	if (status & (BIT5 + BIT4 + BIT3)) {
2223 		// another transmit buffer has completed
2224 		// run bottom half to get more send data from user
2225 		info->pending_bh |= BH_TRANSMIT;
2226 	}
2227 }
2228 
2229 /*
2230  * return true if there are unsent tx DMA buffers, otherwise false
2231  *
2232  * if there are unsent buffers then info->tbuf_start
2233  * is set to index of first unsent buffer
2234  */
2235 static bool unsent_tbufs(struct slgt_info *info)
2236 {
2237 	unsigned int i = info->tbuf_current;
2238 	bool rc = false;
2239 
2240 	/*
2241 	 * search backwards from last loaded buffer (precedes tbuf_current)
2242 	 * for first unsent buffer (desc_count > 0)
2243 	 */
2244 
2245 	do {
2246 		if (i)
2247 			i--;
2248 		else
2249 			i = info->tbuf_count - 1;
2250 		if (!desc_count(info->tbufs[i]))
2251 			break;
2252 		info->tbuf_start = i;
2253 		rc = true;
2254 	} while (i != info->tbuf_current);
2255 
2256 	return rc;
2257 }
2258 
2259 static void isr_txeom(struct slgt_info *info, unsigned short status)
2260 {
2261 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2262 
2263 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2264 	tdma_reset(info);
2265 	if (status & IRQ_TXUNDER) {
2266 		unsigned short val = rd_reg16(info, TCR);
2267 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2268 		wr_reg16(info, TCR, val); /* clear reset bit */
2269 	}
2270 
2271 	if (info->tx_active) {
2272 		if (info->params.mode != MGSL_MODE_ASYNC) {
2273 			if (status & IRQ_TXUNDER)
2274 				info->icount.txunder++;
2275 			else if (status & IRQ_TXIDLE)
2276 				info->icount.txok++;
2277 		}
2278 
2279 		if (unsent_tbufs(info)) {
2280 			tx_start(info);
2281 			update_tx_timer(info);
2282 			return;
2283 		}
2284 		info->tx_active = false;
2285 
2286 		del_timer(&info->tx_timer);
2287 
2288 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2289 			info->signals &= ~SerialSignal_RTS;
2290 			info->drop_rts_on_tx_done = false;
2291 			set_signals(info);
2292 		}
2293 
2294 #if SYNCLINK_GENERIC_HDLC
2295 		if (info->netcount)
2296 			hdlcdev_tx_done(info);
2297 		else
2298 #endif
2299 		{
2300 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2301 				tx_stop(info);
2302 				return;
2303 			}
2304 			info->pending_bh |= BH_TRANSMIT;
2305 		}
2306 	}
2307 }
2308 
2309 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2310 {
2311 	struct cond_wait *w, *prev;
2312 
2313 	/* wake processes waiting for specific transitions */
2314 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2315 		if (w->data & changed) {
2316 			w->data = state;
2317 			wake_up_interruptible(&w->q);
2318 			if (prev != NULL)
2319 				prev->next = w->next;
2320 			else
2321 				info->gpio_wait_q = w->next;
2322 		} else
2323 			prev = w;
2324 	}
2325 }
2326 
2327 /* interrupt service routine
2328  *
2329  * 	irq	interrupt number
2330  * 	dev_id	device ID supplied during interrupt registration
2331  */
2332 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2333 {
2334 	struct slgt_info *info = dev_id;
2335 	unsigned int gsr;
2336 	unsigned int i;
2337 
2338 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2339 
2340 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2341 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2342 		info->irq_occurred = true;
2343 		for(i=0; i < info->port_count ; i++) {
2344 			if (info->port_array[i] == NULL)
2345 				continue;
2346 			spin_lock(&info->port_array[i]->lock);
2347 			if (gsr & (BIT8 << i))
2348 				isr_serial(info->port_array[i]);
2349 			if (gsr & (BIT16 << (i*2)))
2350 				isr_rdma(info->port_array[i]);
2351 			if (gsr & (BIT17 << (i*2)))
2352 				isr_tdma(info->port_array[i]);
2353 			spin_unlock(&info->port_array[i]->lock);
2354 		}
2355 	}
2356 
2357 	if (info->gpio_present) {
2358 		unsigned int state;
2359 		unsigned int changed;
2360 		spin_lock(&info->lock);
2361 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2362 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2363 			/* read latched state of GPIO signals */
2364 			state = rd_reg32(info, IOVR);
2365 			/* clear pending GPIO interrupt bits */
2366 			wr_reg32(info, IOSR, changed);
2367 			for (i=0 ; i < info->port_count ; i++) {
2368 				if (info->port_array[i] != NULL)
2369 					isr_gpio(info->port_array[i], changed, state);
2370 			}
2371 		}
2372 		spin_unlock(&info->lock);
2373 	}
2374 
2375 	for(i=0; i < info->port_count ; i++) {
2376 		struct slgt_info *port = info->port_array[i];
2377 		if (port == NULL)
2378 			continue;
2379 		spin_lock(&port->lock);
2380 		if ((port->port.count || port->netcount) &&
2381 		    port->pending_bh && !port->bh_running &&
2382 		    !port->bh_requested) {
2383 			DBGISR(("%s bh queued\n", port->device_name));
2384 			schedule_work(&port->task);
2385 			port->bh_requested = true;
2386 		}
2387 		spin_unlock(&port->lock);
2388 	}
2389 
2390 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2391 	return IRQ_HANDLED;
2392 }
2393 
2394 static int startup(struct slgt_info *info)
2395 {
2396 	DBGINFO(("%s startup\n", info->device_name));
2397 
2398 	if (tty_port_initialized(&info->port))
2399 		return 0;
2400 
2401 	if (!info->tx_buf) {
2402 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2403 		if (!info->tx_buf) {
2404 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2405 			return -ENOMEM;
2406 		}
2407 	}
2408 
2409 	info->pending_bh = 0;
2410 
2411 	memset(&info->icount, 0, sizeof(info->icount));
2412 
2413 	/* program hardware for current parameters */
2414 	change_params(info);
2415 
2416 	if (info->port.tty)
2417 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2418 
2419 	tty_port_set_initialized(&info->port, 1);
2420 
2421 	return 0;
2422 }
2423 
2424 /*
2425  *  called by close() and hangup() to shutdown hardware
2426  */
2427 static void shutdown(struct slgt_info *info)
2428 {
2429 	unsigned long flags;
2430 
2431 	if (!tty_port_initialized(&info->port))
2432 		return;
2433 
2434 	DBGINFO(("%s shutdown\n", info->device_name));
2435 
2436 	/* clear status wait queue because status changes */
2437 	/* can't happen after shutting down the hardware */
2438 	wake_up_interruptible(&info->status_event_wait_q);
2439 	wake_up_interruptible(&info->event_wait_q);
2440 
2441 	del_timer_sync(&info->tx_timer);
2442 	del_timer_sync(&info->rx_timer);
2443 
2444 	kfree(info->tx_buf);
2445 	info->tx_buf = NULL;
2446 
2447 	spin_lock_irqsave(&info->lock,flags);
2448 
2449 	tx_stop(info);
2450 	rx_stop(info);
2451 
2452 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2453 
2454  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2455 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2456 		set_signals(info);
2457 	}
2458 
2459 	flush_cond_wait(&info->gpio_wait_q);
2460 
2461 	spin_unlock_irqrestore(&info->lock,flags);
2462 
2463 	if (info->port.tty)
2464 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2465 
2466 	tty_port_set_initialized(&info->port, 0);
2467 }
2468 
2469 static void program_hw(struct slgt_info *info)
2470 {
2471 	unsigned long flags;
2472 
2473 	spin_lock_irqsave(&info->lock,flags);
2474 
2475 	rx_stop(info);
2476 	tx_stop(info);
2477 
2478 	if (info->params.mode != MGSL_MODE_ASYNC ||
2479 	    info->netcount)
2480 		sync_mode(info);
2481 	else
2482 		async_mode(info);
2483 
2484 	set_signals(info);
2485 
2486 	info->dcd_chkcount = 0;
2487 	info->cts_chkcount = 0;
2488 	info->ri_chkcount = 0;
2489 	info->dsr_chkcount = 0;
2490 
2491 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2492 	get_signals(info);
2493 
2494 	if (info->netcount ||
2495 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2496 		rx_start(info);
2497 
2498 	spin_unlock_irqrestore(&info->lock,flags);
2499 }
2500 
2501 /*
2502  * reconfigure adapter based on new parameters
2503  */
2504 static void change_params(struct slgt_info *info)
2505 {
2506 	unsigned cflag;
2507 	int bits_per_char;
2508 
2509 	if (!info->port.tty)
2510 		return;
2511 	DBGINFO(("%s change_params\n", info->device_name));
2512 
2513 	cflag = info->port.tty->termios.c_cflag;
2514 
2515 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2516 	/* otherwise assert RTS and DTR */
2517  	if (cflag & CBAUD)
2518 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2519 	else
2520 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2521 
2522 	/* byte size and parity */
2523 
2524 	switch (cflag & CSIZE) {
2525 	case CS5: info->params.data_bits = 5; break;
2526 	case CS6: info->params.data_bits = 6; break;
2527 	case CS7: info->params.data_bits = 7; break;
2528 	case CS8: info->params.data_bits = 8; break;
2529 	default:  info->params.data_bits = 7; break;
2530 	}
2531 
2532 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2533 
2534 	if (cflag & PARENB)
2535 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2536 	else
2537 		info->params.parity = ASYNC_PARITY_NONE;
2538 
2539 	/* calculate number of jiffies to transmit a full
2540 	 * FIFO (32 bytes) at specified data rate
2541 	 */
2542 	bits_per_char = info->params.data_bits +
2543 			info->params.stop_bits + 1;
2544 
2545 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2546 
2547 	if (info->params.data_rate) {
2548 		info->timeout = (32*HZ*bits_per_char) /
2549 				info->params.data_rate;
2550 	}
2551 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2552 
2553 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2554 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2555 
2556 	/* process tty input control flags */
2557 
2558 	info->read_status_mask = IRQ_RXOVER;
2559 	if (I_INPCK(info->port.tty))
2560 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2561 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2562 		info->read_status_mask |= MASK_BREAK;
2563 	if (I_IGNPAR(info->port.tty))
2564 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2565 	if (I_IGNBRK(info->port.tty)) {
2566 		info->ignore_status_mask |= MASK_BREAK;
2567 		/* If ignoring parity and break indicators, ignore
2568 		 * overruns too.  (For real raw support).
2569 		 */
2570 		if (I_IGNPAR(info->port.tty))
2571 			info->ignore_status_mask |= MASK_OVERRUN;
2572 	}
2573 
2574 	program_hw(info);
2575 }
2576 
2577 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2578 {
2579 	DBGINFO(("%s get_stats\n",  info->device_name));
2580 	if (!user_icount) {
2581 		memset(&info->icount, 0, sizeof(info->icount));
2582 	} else {
2583 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2584 			return -EFAULT;
2585 	}
2586 	return 0;
2587 }
2588 
2589 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2590 {
2591 	DBGINFO(("%s get_params\n", info->device_name));
2592 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2593 		return -EFAULT;
2594 	return 0;
2595 }
2596 
2597 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2598 {
2599  	unsigned long flags;
2600 	MGSL_PARAMS tmp_params;
2601 
2602 	DBGINFO(("%s set_params\n", info->device_name));
2603 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2604 		return -EFAULT;
2605 
2606 	spin_lock_irqsave(&info->lock, flags);
2607 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2608 		info->base_clock = tmp_params.clock_speed;
2609 	else
2610 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2611 	spin_unlock_irqrestore(&info->lock, flags);
2612 
2613 	program_hw(info);
2614 
2615 	return 0;
2616 }
2617 
2618 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2619 {
2620 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2621 	if (put_user(info->idle_mode, idle_mode))
2622 		return -EFAULT;
2623 	return 0;
2624 }
2625 
2626 static int set_txidle(struct slgt_info *info, int idle_mode)
2627 {
2628  	unsigned long flags;
2629 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2630 	spin_lock_irqsave(&info->lock,flags);
2631 	info->idle_mode = idle_mode;
2632 	if (info->params.mode != MGSL_MODE_ASYNC)
2633 		tx_set_idle(info);
2634 	spin_unlock_irqrestore(&info->lock,flags);
2635 	return 0;
2636 }
2637 
2638 static int tx_enable(struct slgt_info *info, int enable)
2639 {
2640  	unsigned long flags;
2641 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2642 	spin_lock_irqsave(&info->lock,flags);
2643 	if (enable) {
2644 		if (!info->tx_enabled)
2645 			tx_start(info);
2646 	} else {
2647 		if (info->tx_enabled)
2648 			tx_stop(info);
2649 	}
2650 	spin_unlock_irqrestore(&info->lock,flags);
2651 	return 0;
2652 }
2653 
2654 /*
2655  * abort transmit HDLC frame
2656  */
2657 static int tx_abort(struct slgt_info *info)
2658 {
2659  	unsigned long flags;
2660 	DBGINFO(("%s tx_abort\n", info->device_name));
2661 	spin_lock_irqsave(&info->lock,flags);
2662 	tdma_reset(info);
2663 	spin_unlock_irqrestore(&info->lock,flags);
2664 	return 0;
2665 }
2666 
2667 static int rx_enable(struct slgt_info *info, int enable)
2668 {
2669  	unsigned long flags;
2670 	unsigned int rbuf_fill_level;
2671 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2672 	spin_lock_irqsave(&info->lock,flags);
2673 	/*
2674 	 * enable[31..16] = receive DMA buffer fill level
2675 	 * 0 = noop (leave fill level unchanged)
2676 	 * fill level must be multiple of 4 and <= buffer size
2677 	 */
2678 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2679 	if (rbuf_fill_level) {
2680 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2681 			spin_unlock_irqrestore(&info->lock, flags);
2682 			return -EINVAL;
2683 		}
2684 		info->rbuf_fill_level = rbuf_fill_level;
2685 		if (rbuf_fill_level < 128)
2686 			info->rx_pio = 1; /* PIO mode */
2687 		else
2688 			info->rx_pio = 0; /* DMA mode */
2689 		rx_stop(info); /* restart receiver to use new fill level */
2690 	}
2691 
2692 	/*
2693 	 * enable[1..0] = receiver enable command
2694 	 * 0 = disable
2695 	 * 1 = enable
2696 	 * 2 = enable or force hunt mode if already enabled
2697 	 */
2698 	enable &= 3;
2699 	if (enable) {
2700 		if (!info->rx_enabled)
2701 			rx_start(info);
2702 		else if (enable == 2) {
2703 			/* force hunt mode (write 1 to RCR[3]) */
2704 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2705 		}
2706 	} else {
2707 		if (info->rx_enabled)
2708 			rx_stop(info);
2709 	}
2710 	spin_unlock_irqrestore(&info->lock,flags);
2711 	return 0;
2712 }
2713 
2714 /*
2715  *  wait for specified event to occur
2716  */
2717 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2718 {
2719  	unsigned long flags;
2720 	int s;
2721 	int rc=0;
2722 	struct mgsl_icount cprev, cnow;
2723 	int events;
2724 	int mask;
2725 	struct	_input_signal_events oldsigs, newsigs;
2726 	DECLARE_WAITQUEUE(wait, current);
2727 
2728 	if (get_user(mask, mask_ptr))
2729 		return -EFAULT;
2730 
2731 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2732 
2733 	spin_lock_irqsave(&info->lock,flags);
2734 
2735 	/* return immediately if state matches requested events */
2736 	get_signals(info);
2737 	s = info->signals;
2738 
2739 	events = mask &
2740 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2741  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2742 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2743 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2744 	if (events) {
2745 		spin_unlock_irqrestore(&info->lock,flags);
2746 		goto exit;
2747 	}
2748 
2749 	/* save current irq counts */
2750 	cprev = info->icount;
2751 	oldsigs = info->input_signal_events;
2752 
2753 	/* enable hunt and idle irqs if needed */
2754 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2755 		unsigned short val = rd_reg16(info, SCR);
2756 		if (!(val & IRQ_RXIDLE))
2757 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2758 	}
2759 
2760 	set_current_state(TASK_INTERRUPTIBLE);
2761 	add_wait_queue(&info->event_wait_q, &wait);
2762 
2763 	spin_unlock_irqrestore(&info->lock,flags);
2764 
2765 	for(;;) {
2766 		schedule();
2767 		if (signal_pending(current)) {
2768 			rc = -ERESTARTSYS;
2769 			break;
2770 		}
2771 
2772 		/* get current irq counts */
2773 		spin_lock_irqsave(&info->lock,flags);
2774 		cnow = info->icount;
2775 		newsigs = info->input_signal_events;
2776 		set_current_state(TASK_INTERRUPTIBLE);
2777 		spin_unlock_irqrestore(&info->lock,flags);
2778 
2779 		/* if no change, wait aborted for some reason */
2780 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2781 		    newsigs.dsr_down == oldsigs.dsr_down &&
2782 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2783 		    newsigs.dcd_down == oldsigs.dcd_down &&
2784 		    newsigs.cts_up   == oldsigs.cts_up   &&
2785 		    newsigs.cts_down == oldsigs.cts_down &&
2786 		    newsigs.ri_up    == oldsigs.ri_up    &&
2787 		    newsigs.ri_down  == oldsigs.ri_down  &&
2788 		    cnow.exithunt    == cprev.exithunt   &&
2789 		    cnow.rxidle      == cprev.rxidle) {
2790 			rc = -EIO;
2791 			break;
2792 		}
2793 
2794 		events = mask &
2795 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2796 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2797 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2798 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2799 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2800 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2801 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2802 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2803 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2804 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2805 		if (events)
2806 			break;
2807 
2808 		cprev = cnow;
2809 		oldsigs = newsigs;
2810 	}
2811 
2812 	remove_wait_queue(&info->event_wait_q, &wait);
2813 	set_current_state(TASK_RUNNING);
2814 
2815 
2816 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2817 		spin_lock_irqsave(&info->lock,flags);
2818 		if (!waitqueue_active(&info->event_wait_q)) {
2819 			/* disable enable exit hunt mode/idle rcvd IRQs */
2820 			wr_reg16(info, SCR,
2821 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2822 		}
2823 		spin_unlock_irqrestore(&info->lock,flags);
2824 	}
2825 exit:
2826 	if (rc == 0)
2827 		rc = put_user(events, mask_ptr);
2828 	return rc;
2829 }
2830 
2831 static int get_interface(struct slgt_info *info, int __user *if_mode)
2832 {
2833 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2834 	if (put_user(info->if_mode, if_mode))
2835 		return -EFAULT;
2836 	return 0;
2837 }
2838 
2839 static int set_interface(struct slgt_info *info, int if_mode)
2840 {
2841  	unsigned long flags;
2842 	unsigned short val;
2843 
2844 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2845 	spin_lock_irqsave(&info->lock,flags);
2846 	info->if_mode = if_mode;
2847 
2848 	msc_set_vcr(info);
2849 
2850 	/* TCR (tx control) 07  1=RTS driver control */
2851 	val = rd_reg16(info, TCR);
2852 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2853 		val |= BIT7;
2854 	else
2855 		val &= ~BIT7;
2856 	wr_reg16(info, TCR, val);
2857 
2858 	spin_unlock_irqrestore(&info->lock,flags);
2859 	return 0;
2860 }
2861 
2862 static int get_xsync(struct slgt_info *info, int __user *xsync)
2863 {
2864 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2865 	if (put_user(info->xsync, xsync))
2866 		return -EFAULT;
2867 	return 0;
2868 }
2869 
2870 /*
2871  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2872  *
2873  * sync pattern is contained in least significant bytes of value
2874  * most significant byte of sync pattern is oldest (1st sent/detected)
2875  */
2876 static int set_xsync(struct slgt_info *info, int xsync)
2877 {
2878 	unsigned long flags;
2879 
2880 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2881 	spin_lock_irqsave(&info->lock, flags);
2882 	info->xsync = xsync;
2883 	wr_reg32(info, XSR, xsync);
2884 	spin_unlock_irqrestore(&info->lock, flags);
2885 	return 0;
2886 }
2887 
2888 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2889 {
2890 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2891 	if (put_user(info->xctrl, xctrl))
2892 		return -EFAULT;
2893 	return 0;
2894 }
2895 
2896 /*
2897  * set extended control options
2898  *
2899  * xctrl[31:19] reserved, must be zero
2900  * xctrl[18:17] extended sync pattern length in bytes
2901  *              00 = 1 byte  in xsr[7:0]
2902  *              01 = 2 bytes in xsr[15:0]
2903  *              10 = 3 bytes in xsr[23:0]
2904  *              11 = 4 bytes in xsr[31:0]
2905  * xctrl[16]    1 = enable terminal count, 0=disabled
2906  * xctrl[15:0]  receive terminal count for fixed length packets
2907  *              value is count minus one (0 = 1 byte packet)
2908  *              when terminal count is reached, receiver
2909  *              automatically returns to hunt mode and receive
2910  *              FIFO contents are flushed to DMA buffers with
2911  *              end of frame (EOF) status
2912  */
2913 static int set_xctrl(struct slgt_info *info, int xctrl)
2914 {
2915 	unsigned long flags;
2916 
2917 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2918 	spin_lock_irqsave(&info->lock, flags);
2919 	info->xctrl = xctrl;
2920 	wr_reg32(info, XCR, xctrl);
2921 	spin_unlock_irqrestore(&info->lock, flags);
2922 	return 0;
2923 }
2924 
2925 /*
2926  * set general purpose IO pin state and direction
2927  *
2928  * user_gpio fields:
2929  * state   each bit indicates a pin state
2930  * smask   set bit indicates pin state to set
2931  * dir     each bit indicates a pin direction (0=input, 1=output)
2932  * dmask   set bit indicates pin direction to set
2933  */
2934 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2935 {
2936  	unsigned long flags;
2937 	struct gpio_desc gpio;
2938 	__u32 data;
2939 
2940 	if (!info->gpio_present)
2941 		return -EINVAL;
2942 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2943 		return -EFAULT;
2944 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2945 		 info->device_name, gpio.state, gpio.smask,
2946 		 gpio.dir, gpio.dmask));
2947 
2948 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2949 	if (gpio.dmask) {
2950 		data = rd_reg32(info, IODR);
2951 		data |= gpio.dmask & gpio.dir;
2952 		data &= ~(gpio.dmask & ~gpio.dir);
2953 		wr_reg32(info, IODR, data);
2954 	}
2955 	if (gpio.smask) {
2956 		data = rd_reg32(info, IOVR);
2957 		data |= gpio.smask & gpio.state;
2958 		data &= ~(gpio.smask & ~gpio.state);
2959 		wr_reg32(info, IOVR, data);
2960 	}
2961 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2962 
2963 	return 0;
2964 }
2965 
2966 /*
2967  * get general purpose IO pin state and direction
2968  */
2969 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2970 {
2971 	struct gpio_desc gpio;
2972 	if (!info->gpio_present)
2973 		return -EINVAL;
2974 	gpio.state = rd_reg32(info, IOVR);
2975 	gpio.smask = 0xffffffff;
2976 	gpio.dir   = rd_reg32(info, IODR);
2977 	gpio.dmask = 0xffffffff;
2978 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2979 		return -EFAULT;
2980 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2981 		 info->device_name, gpio.state, gpio.dir));
2982 	return 0;
2983 }
2984 
2985 /*
2986  * conditional wait facility
2987  */
2988 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2989 {
2990 	init_waitqueue_head(&w->q);
2991 	init_waitqueue_entry(&w->wait, current);
2992 	w->data = data;
2993 }
2994 
2995 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2996 {
2997 	set_current_state(TASK_INTERRUPTIBLE);
2998 	add_wait_queue(&w->q, &w->wait);
2999 	w->next = *head;
3000 	*head = w;
3001 }
3002 
3003 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3004 {
3005 	struct cond_wait *w, *prev;
3006 	remove_wait_queue(&cw->q, &cw->wait);
3007 	set_current_state(TASK_RUNNING);
3008 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3009 		if (w == cw) {
3010 			if (prev != NULL)
3011 				prev->next = w->next;
3012 			else
3013 				*head = w->next;
3014 			break;
3015 		}
3016 	}
3017 }
3018 
3019 static void flush_cond_wait(struct cond_wait **head)
3020 {
3021 	while (*head != NULL) {
3022 		wake_up_interruptible(&(*head)->q);
3023 		*head = (*head)->next;
3024 	}
3025 }
3026 
3027 /*
3028  * wait for general purpose I/O pin(s) to enter specified state
3029  *
3030  * user_gpio fields:
3031  * state - bit indicates target pin state
3032  * smask - set bit indicates watched pin
3033  *
3034  * The wait ends when at least one watched pin enters the specified
3035  * state. When 0 (no error) is returned, user_gpio->state is set to the
3036  * state of all GPIO pins when the wait ends.
3037  *
3038  * Note: Each pin may be a dedicated input, dedicated output, or
3039  * configurable input/output. The number and configuration of pins
3040  * varies with the specific adapter model. Only input pins (dedicated
3041  * or configured) can be monitored with this function.
3042  */
3043 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3044 {
3045  	unsigned long flags;
3046 	int rc = 0;
3047 	struct gpio_desc gpio;
3048 	struct cond_wait wait;
3049 	u32 state;
3050 
3051 	if (!info->gpio_present)
3052 		return -EINVAL;
3053 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3054 		return -EFAULT;
3055 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3056 		 info->device_name, gpio.state, gpio.smask));
3057 	/* ignore output pins identified by set IODR bit */
3058 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3059 		return -EINVAL;
3060 	init_cond_wait(&wait, gpio.smask);
3061 
3062 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3063 	/* enable interrupts for watched pins */
3064 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3065 	/* get current pin states */
3066 	state = rd_reg32(info, IOVR);
3067 
3068 	if (gpio.smask & ~(state ^ gpio.state)) {
3069 		/* already in target state */
3070 		gpio.state = state;
3071 	} else {
3072 		/* wait for target state */
3073 		add_cond_wait(&info->gpio_wait_q, &wait);
3074 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3075 		schedule();
3076 		if (signal_pending(current))
3077 			rc = -ERESTARTSYS;
3078 		else
3079 			gpio.state = wait.data;
3080 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3081 		remove_cond_wait(&info->gpio_wait_q, &wait);
3082 	}
3083 
3084 	/* disable all GPIO interrupts if no waiting processes */
3085 	if (info->gpio_wait_q == NULL)
3086 		wr_reg32(info, IOER, 0);
3087 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3088 
3089 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3090 		rc = -EFAULT;
3091 	return rc;
3092 }
3093 
3094 static int modem_input_wait(struct slgt_info *info,int arg)
3095 {
3096  	unsigned long flags;
3097 	int rc;
3098 	struct mgsl_icount cprev, cnow;
3099 	DECLARE_WAITQUEUE(wait, current);
3100 
3101 	/* save current irq counts */
3102 	spin_lock_irqsave(&info->lock,flags);
3103 	cprev = info->icount;
3104 	add_wait_queue(&info->status_event_wait_q, &wait);
3105 	set_current_state(TASK_INTERRUPTIBLE);
3106 	spin_unlock_irqrestore(&info->lock,flags);
3107 
3108 	for(;;) {
3109 		schedule();
3110 		if (signal_pending(current)) {
3111 			rc = -ERESTARTSYS;
3112 			break;
3113 		}
3114 
3115 		/* get new irq counts */
3116 		spin_lock_irqsave(&info->lock,flags);
3117 		cnow = info->icount;
3118 		set_current_state(TASK_INTERRUPTIBLE);
3119 		spin_unlock_irqrestore(&info->lock,flags);
3120 
3121 		/* if no change, wait aborted for some reason */
3122 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3123 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3124 			rc = -EIO;
3125 			break;
3126 		}
3127 
3128 		/* check for change in caller specified modem input */
3129 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3130 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3131 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3132 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3133 			rc = 0;
3134 			break;
3135 		}
3136 
3137 		cprev = cnow;
3138 	}
3139 	remove_wait_queue(&info->status_event_wait_q, &wait);
3140 	set_current_state(TASK_RUNNING);
3141 	return rc;
3142 }
3143 
3144 /*
3145  *  return state of serial control and status signals
3146  */
3147 static int tiocmget(struct tty_struct *tty)
3148 {
3149 	struct slgt_info *info = tty->driver_data;
3150 	unsigned int result;
3151  	unsigned long flags;
3152 
3153 	spin_lock_irqsave(&info->lock,flags);
3154  	get_signals(info);
3155 	spin_unlock_irqrestore(&info->lock,flags);
3156 
3157 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3158 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3159 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3160 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3161 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3162 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3163 
3164 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3165 	return result;
3166 }
3167 
3168 /*
3169  * set modem control signals (DTR/RTS)
3170  *
3171  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3172  *		TIOCMSET = set/clear signal values
3173  * 	value	bit mask for command
3174  */
3175 static int tiocmset(struct tty_struct *tty,
3176 		    unsigned int set, unsigned int clear)
3177 {
3178 	struct slgt_info *info = tty->driver_data;
3179  	unsigned long flags;
3180 
3181 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3182 
3183 	if (set & TIOCM_RTS)
3184 		info->signals |= SerialSignal_RTS;
3185 	if (set & TIOCM_DTR)
3186 		info->signals |= SerialSignal_DTR;
3187 	if (clear & TIOCM_RTS)
3188 		info->signals &= ~SerialSignal_RTS;
3189 	if (clear & TIOCM_DTR)
3190 		info->signals &= ~SerialSignal_DTR;
3191 
3192 	spin_lock_irqsave(&info->lock,flags);
3193 	set_signals(info);
3194 	spin_unlock_irqrestore(&info->lock,flags);
3195 	return 0;
3196 }
3197 
3198 static int carrier_raised(struct tty_port *port)
3199 {
3200 	unsigned long flags;
3201 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3202 
3203 	spin_lock_irqsave(&info->lock,flags);
3204 	get_signals(info);
3205 	spin_unlock_irqrestore(&info->lock,flags);
3206 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3207 }
3208 
3209 static void dtr_rts(struct tty_port *port, int on)
3210 {
3211 	unsigned long flags;
3212 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3213 
3214 	spin_lock_irqsave(&info->lock,flags);
3215 	if (on)
3216 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3217 	else
3218 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3219 	set_signals(info);
3220 	spin_unlock_irqrestore(&info->lock,flags);
3221 }
3222 
3223 
3224 /*
3225  *  block current process until the device is ready to open
3226  */
3227 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3228 			   struct slgt_info *info)
3229 {
3230 	DECLARE_WAITQUEUE(wait, current);
3231 	int		retval;
3232 	bool		do_clocal = false;
3233 	unsigned long	flags;
3234 	int		cd;
3235 	struct tty_port *port = &info->port;
3236 
3237 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3238 
3239 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3240 		/* nonblock mode is set or port is not enabled */
3241 		tty_port_set_active(port, 1);
3242 		return 0;
3243 	}
3244 
3245 	if (C_CLOCAL(tty))
3246 		do_clocal = true;
3247 
3248 	/* Wait for carrier detect and the line to become
3249 	 * free (i.e., not in use by the callout).  While we are in
3250 	 * this loop, port->count is dropped by one, so that
3251 	 * close() knows when to free things.  We restore it upon
3252 	 * exit, either normal or abnormal.
3253 	 */
3254 
3255 	retval = 0;
3256 	add_wait_queue(&port->open_wait, &wait);
3257 
3258 	spin_lock_irqsave(&info->lock, flags);
3259 	port->count--;
3260 	spin_unlock_irqrestore(&info->lock, flags);
3261 	port->blocked_open++;
3262 
3263 	while (1) {
3264 		if (C_BAUD(tty) && tty_port_initialized(port))
3265 			tty_port_raise_dtr_rts(port);
3266 
3267 		set_current_state(TASK_INTERRUPTIBLE);
3268 
3269 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3270 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3271 					-EAGAIN : -ERESTARTSYS;
3272 			break;
3273 		}
3274 
3275 		cd = tty_port_carrier_raised(port);
3276 		if (do_clocal || cd)
3277 			break;
3278 
3279 		if (signal_pending(current)) {
3280 			retval = -ERESTARTSYS;
3281 			break;
3282 		}
3283 
3284 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3285 		tty_unlock(tty);
3286 		schedule();
3287 		tty_lock(tty);
3288 	}
3289 
3290 	set_current_state(TASK_RUNNING);
3291 	remove_wait_queue(&port->open_wait, &wait);
3292 
3293 	if (!tty_hung_up_p(filp))
3294 		port->count++;
3295 	port->blocked_open--;
3296 
3297 	if (!retval)
3298 		tty_port_set_active(port, 1);
3299 
3300 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3301 	return retval;
3302 }
3303 
3304 /*
3305  * allocate buffers used for calling line discipline receive_buf
3306  * directly in synchronous mode
3307  * note: add 5 bytes to max frame size to allow appending
3308  * 32-bit CRC and status byte when configured to do so
3309  */
3310 static int alloc_tmp_rbuf(struct slgt_info *info)
3311 {
3312 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3313 	if (info->tmp_rbuf == NULL)
3314 		return -ENOMEM;
3315 	/* unused flag buffer to satisfy receive_buf calling interface */
3316 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3317 	if (!info->flag_buf) {
3318 		kfree(info->tmp_rbuf);
3319 		info->tmp_rbuf = NULL;
3320 		return -ENOMEM;
3321 	}
3322 	return 0;
3323 }
3324 
3325 static void free_tmp_rbuf(struct slgt_info *info)
3326 {
3327 	kfree(info->tmp_rbuf);
3328 	info->tmp_rbuf = NULL;
3329 	kfree(info->flag_buf);
3330 	info->flag_buf = NULL;
3331 }
3332 
3333 /*
3334  * allocate DMA descriptor lists.
3335  */
3336 static int alloc_desc(struct slgt_info *info)
3337 {
3338 	unsigned int i;
3339 	unsigned int pbufs;
3340 
3341 	/* allocate memory to hold descriptor lists */
3342 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3343 					&info->bufs_dma_addr, GFP_KERNEL);
3344 	if (info->bufs == NULL)
3345 		return -ENOMEM;
3346 
3347 	info->rbufs = (struct slgt_desc*)info->bufs;
3348 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3349 
3350 	pbufs = (unsigned int)info->bufs_dma_addr;
3351 
3352 	/*
3353 	 * Build circular lists of descriptors
3354 	 */
3355 
3356 	for (i=0; i < info->rbuf_count; i++) {
3357 		/* physical address of this descriptor */
3358 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3359 
3360 		/* physical address of next descriptor */
3361 		if (i == info->rbuf_count - 1)
3362 			info->rbufs[i].next = cpu_to_le32(pbufs);
3363 		else
3364 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3365 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3366 	}
3367 
3368 	for (i=0; i < info->tbuf_count; i++) {
3369 		/* physical address of this descriptor */
3370 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3371 
3372 		/* physical address of next descriptor */
3373 		if (i == info->tbuf_count - 1)
3374 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3375 		else
3376 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3377 	}
3378 
3379 	return 0;
3380 }
3381 
3382 static void free_desc(struct slgt_info *info)
3383 {
3384 	if (info->bufs != NULL) {
3385 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3386 				  info->bufs, info->bufs_dma_addr);
3387 		info->bufs  = NULL;
3388 		info->rbufs = NULL;
3389 		info->tbufs = NULL;
3390 	}
3391 }
3392 
3393 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3394 {
3395 	int i;
3396 	for (i=0; i < count; i++) {
3397 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3398 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3399 		if (!bufs[i].buf)
3400 			return -ENOMEM;
3401 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3402 	}
3403 	return 0;
3404 }
3405 
3406 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3407 {
3408 	int i;
3409 	for (i=0; i < count; i++) {
3410 		if (bufs[i].buf == NULL)
3411 			continue;
3412 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3413 				  bufs[i].buf_dma_addr);
3414 		bufs[i].buf = NULL;
3415 	}
3416 }
3417 
3418 static int alloc_dma_bufs(struct slgt_info *info)
3419 {
3420 	info->rbuf_count = 32;
3421 	info->tbuf_count = 32;
3422 
3423 	if (alloc_desc(info) < 0 ||
3424 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3425 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3426 	    alloc_tmp_rbuf(info) < 0) {
3427 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3428 		return -ENOMEM;
3429 	}
3430 	reset_rbufs(info);
3431 	return 0;
3432 }
3433 
3434 static void free_dma_bufs(struct slgt_info *info)
3435 {
3436 	if (info->bufs) {
3437 		free_bufs(info, info->rbufs, info->rbuf_count);
3438 		free_bufs(info, info->tbufs, info->tbuf_count);
3439 		free_desc(info);
3440 	}
3441 	free_tmp_rbuf(info);
3442 }
3443 
3444 static int claim_resources(struct slgt_info *info)
3445 {
3446 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3447 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3448 			info->device_name, info->phys_reg_addr));
3449 		info->init_error = DiagStatus_AddressConflict;
3450 		goto errout;
3451 	}
3452 	else
3453 		info->reg_addr_requested = true;
3454 
3455 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3456 	if (!info->reg_addr) {
3457 		DBGERR(("%s can't map device registers, addr=%08X\n",
3458 			info->device_name, info->phys_reg_addr));
3459 		info->init_error = DiagStatus_CantAssignPciResources;
3460 		goto errout;
3461 	}
3462 	return 0;
3463 
3464 errout:
3465 	release_resources(info);
3466 	return -ENODEV;
3467 }
3468 
3469 static void release_resources(struct slgt_info *info)
3470 {
3471 	if (info->irq_requested) {
3472 		free_irq(info->irq_level, info);
3473 		info->irq_requested = false;
3474 	}
3475 
3476 	if (info->reg_addr_requested) {
3477 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3478 		info->reg_addr_requested = false;
3479 	}
3480 
3481 	if (info->reg_addr) {
3482 		iounmap(info->reg_addr);
3483 		info->reg_addr = NULL;
3484 	}
3485 }
3486 
3487 /* Add the specified device instance data structure to the
3488  * global linked list of devices and increment the device count.
3489  */
3490 static void add_device(struct slgt_info *info)
3491 {
3492 	char *devstr;
3493 
3494 	info->next_device = NULL;
3495 	info->line = slgt_device_count;
3496 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3497 
3498 	if (info->line < MAX_DEVICES) {
3499 		if (maxframe[info->line])
3500 			info->max_frame_size = maxframe[info->line];
3501 	}
3502 
3503 	slgt_device_count++;
3504 
3505 	if (!slgt_device_list)
3506 		slgt_device_list = info;
3507 	else {
3508 		struct slgt_info *current_dev = slgt_device_list;
3509 		while(current_dev->next_device)
3510 			current_dev = current_dev->next_device;
3511 		current_dev->next_device = info;
3512 	}
3513 
3514 	if (info->max_frame_size < 4096)
3515 		info->max_frame_size = 4096;
3516 	else if (info->max_frame_size > 65535)
3517 		info->max_frame_size = 65535;
3518 
3519 	switch(info->pdev->device) {
3520 	case SYNCLINK_GT_DEVICE_ID:
3521 		devstr = "GT";
3522 		break;
3523 	case SYNCLINK_GT2_DEVICE_ID:
3524 		devstr = "GT2";
3525 		break;
3526 	case SYNCLINK_GT4_DEVICE_ID:
3527 		devstr = "GT4";
3528 		break;
3529 	case SYNCLINK_AC_DEVICE_ID:
3530 		devstr = "AC";
3531 		info->params.mode = MGSL_MODE_ASYNC;
3532 		break;
3533 	default:
3534 		devstr = "(unknown model)";
3535 	}
3536 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3537 		devstr, info->device_name, info->phys_reg_addr,
3538 		info->irq_level, info->max_frame_size);
3539 
3540 #if SYNCLINK_GENERIC_HDLC
3541 	hdlcdev_init(info);
3542 #endif
3543 }
3544 
3545 static const struct tty_port_operations slgt_port_ops = {
3546 	.carrier_raised = carrier_raised,
3547 	.dtr_rts = dtr_rts,
3548 };
3549 
3550 /*
3551  *  allocate device instance structure, return NULL on failure
3552  */
3553 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3554 {
3555 	struct slgt_info *info;
3556 
3557 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3558 
3559 	if (!info) {
3560 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3561 			driver_name, adapter_num, port_num));
3562 	} else {
3563 		tty_port_init(&info->port);
3564 		info->port.ops = &slgt_port_ops;
3565 		info->magic = MGSL_MAGIC;
3566 		INIT_WORK(&info->task, bh_handler);
3567 		info->max_frame_size = 4096;
3568 		info->base_clock = 14745600;
3569 		info->rbuf_fill_level = DMABUFSIZE;
3570 		info->port.close_delay = 5*HZ/10;
3571 		info->port.closing_wait = 30*HZ;
3572 		init_waitqueue_head(&info->status_event_wait_q);
3573 		init_waitqueue_head(&info->event_wait_q);
3574 		spin_lock_init(&info->netlock);
3575 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3576 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3577 		info->adapter_num = adapter_num;
3578 		info->port_num = port_num;
3579 
3580 		timer_setup(&info->tx_timer, tx_timeout, 0);
3581 		timer_setup(&info->rx_timer, rx_timeout, 0);
3582 
3583 		/* Copy configuration info to device instance data */
3584 		info->pdev = pdev;
3585 		info->irq_level = pdev->irq;
3586 		info->phys_reg_addr = pci_resource_start(pdev,0);
3587 
3588 		info->bus_type = MGSL_BUS_TYPE_PCI;
3589 		info->irq_flags = IRQF_SHARED;
3590 
3591 		info->init_error = -1; /* assume error, set to 0 on successful init */
3592 	}
3593 
3594 	return info;
3595 }
3596 
3597 static void device_init(int adapter_num, struct pci_dev *pdev)
3598 {
3599 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3600 	int i;
3601 	int port_count = 1;
3602 
3603 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3604 		port_count = 2;
3605 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3606 		port_count = 4;
3607 
3608 	/* allocate device instances for all ports */
3609 	for (i=0; i < port_count; ++i) {
3610 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3611 		if (port_array[i] == NULL) {
3612 			for (--i; i >= 0; --i) {
3613 				tty_port_destroy(&port_array[i]->port);
3614 				kfree(port_array[i]);
3615 			}
3616 			return;
3617 		}
3618 	}
3619 
3620 	/* give copy of port_array to all ports and add to device list  */
3621 	for (i=0; i < port_count; ++i) {
3622 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3623 		add_device(port_array[i]);
3624 		port_array[i]->port_count = port_count;
3625 		spin_lock_init(&port_array[i]->lock);
3626 	}
3627 
3628 	/* Allocate and claim adapter resources */
3629 	if (!claim_resources(port_array[0])) {
3630 
3631 		alloc_dma_bufs(port_array[0]);
3632 
3633 		/* copy resource information from first port to others */
3634 		for (i = 1; i < port_count; ++i) {
3635 			port_array[i]->irq_level = port_array[0]->irq_level;
3636 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3637 			alloc_dma_bufs(port_array[i]);
3638 		}
3639 
3640 		if (request_irq(port_array[0]->irq_level,
3641 					slgt_interrupt,
3642 					port_array[0]->irq_flags,
3643 					port_array[0]->device_name,
3644 					port_array[0]) < 0) {
3645 			DBGERR(("%s request_irq failed IRQ=%d\n",
3646 				port_array[0]->device_name,
3647 				port_array[0]->irq_level));
3648 		} else {
3649 			port_array[0]->irq_requested = true;
3650 			adapter_test(port_array[0]);
3651 			for (i=1 ; i < port_count ; i++) {
3652 				port_array[i]->init_error = port_array[0]->init_error;
3653 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3654 			}
3655 		}
3656 	}
3657 
3658 	for (i = 0; i < port_count; ++i) {
3659 		struct slgt_info *info = port_array[i];
3660 		tty_port_register_device(&info->port, serial_driver, info->line,
3661 				&info->pdev->dev);
3662 	}
3663 }
3664 
3665 static int init_one(struct pci_dev *dev,
3666 			      const struct pci_device_id *ent)
3667 {
3668 	if (pci_enable_device(dev)) {
3669 		printk("error enabling pci device %p\n", dev);
3670 		return -EIO;
3671 	}
3672 	pci_set_master(dev);
3673 	device_init(slgt_device_count, dev);
3674 	return 0;
3675 }
3676 
3677 static void remove_one(struct pci_dev *dev)
3678 {
3679 }
3680 
3681 static const struct tty_operations ops = {
3682 	.open = open,
3683 	.close = close,
3684 	.write = write,
3685 	.put_char = put_char,
3686 	.flush_chars = flush_chars,
3687 	.write_room = write_room,
3688 	.chars_in_buffer = chars_in_buffer,
3689 	.flush_buffer = flush_buffer,
3690 	.ioctl = ioctl,
3691 	.compat_ioctl = slgt_compat_ioctl,
3692 	.throttle = throttle,
3693 	.unthrottle = unthrottle,
3694 	.send_xchar = send_xchar,
3695 	.break_ctl = set_break,
3696 	.wait_until_sent = wait_until_sent,
3697 	.set_termios = set_termios,
3698 	.stop = tx_hold,
3699 	.start = tx_release,
3700 	.hangup = hangup,
3701 	.tiocmget = tiocmget,
3702 	.tiocmset = tiocmset,
3703 	.get_icount = get_icount,
3704 	.proc_show = synclink_gt_proc_show,
3705 };
3706 
3707 static void slgt_cleanup(void)
3708 {
3709 	int rc;
3710 	struct slgt_info *info;
3711 	struct slgt_info *tmp;
3712 
3713 	printk(KERN_INFO "unload %s\n", driver_name);
3714 
3715 	if (serial_driver) {
3716 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3717 			tty_unregister_device(serial_driver, info->line);
3718 		rc = tty_unregister_driver(serial_driver);
3719 		if (rc)
3720 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3721 		put_tty_driver(serial_driver);
3722 	}
3723 
3724 	/* reset devices */
3725 	info = slgt_device_list;
3726 	while(info) {
3727 		reset_port(info);
3728 		info = info->next_device;
3729 	}
3730 
3731 	/* release devices */
3732 	info = slgt_device_list;
3733 	while(info) {
3734 #if SYNCLINK_GENERIC_HDLC
3735 		hdlcdev_exit(info);
3736 #endif
3737 		free_dma_bufs(info);
3738 		free_tmp_rbuf(info);
3739 		if (info->port_num == 0)
3740 			release_resources(info);
3741 		tmp = info;
3742 		info = info->next_device;
3743 		tty_port_destroy(&tmp->port);
3744 		kfree(tmp);
3745 	}
3746 
3747 	if (pci_registered)
3748 		pci_unregister_driver(&pci_driver);
3749 }
3750 
3751 /*
3752  *  Driver initialization entry point.
3753  */
3754 static int __init slgt_init(void)
3755 {
3756 	int rc;
3757 
3758 	printk(KERN_INFO "%s\n", driver_name);
3759 
3760 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3761 	if (!serial_driver) {
3762 		printk("%s can't allocate tty driver\n", driver_name);
3763 		return -ENOMEM;
3764 	}
3765 
3766 	/* Initialize the tty_driver structure */
3767 
3768 	serial_driver->driver_name = slgt_driver_name;
3769 	serial_driver->name = tty_dev_prefix;
3770 	serial_driver->major = ttymajor;
3771 	serial_driver->minor_start = 64;
3772 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3773 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3774 	serial_driver->init_termios = tty_std_termios;
3775 	serial_driver->init_termios.c_cflag =
3776 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3777 	serial_driver->init_termios.c_ispeed = 9600;
3778 	serial_driver->init_termios.c_ospeed = 9600;
3779 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3780 	tty_set_operations(serial_driver, &ops);
3781 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3782 		DBGERR(("%s can't register serial driver\n", driver_name));
3783 		put_tty_driver(serial_driver);
3784 		serial_driver = NULL;
3785 		goto error;
3786 	}
3787 
3788 	printk(KERN_INFO "%s, tty major#%d\n",
3789 	       driver_name, serial_driver->major);
3790 
3791 	slgt_device_count = 0;
3792 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3793 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3794 		goto error;
3795 	}
3796 	pci_registered = true;
3797 
3798 	if (!slgt_device_list)
3799 		printk("%s no devices found\n",driver_name);
3800 
3801 	return 0;
3802 
3803 error:
3804 	slgt_cleanup();
3805 	return rc;
3806 }
3807 
3808 static void __exit slgt_exit(void)
3809 {
3810 	slgt_cleanup();
3811 }
3812 
3813 module_init(slgt_init);
3814 module_exit(slgt_exit);
3815 
3816 /*
3817  * register access routines
3818  */
3819 
3820 #define CALC_REGADDR() \
3821 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3822 	if (addr >= 0x80) \
3823 		reg_addr += (info->port_num) * 32; \
3824 	else if (addr >= 0x40)	\
3825 		reg_addr += (info->port_num) * 16;
3826 
3827 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3828 {
3829 	CALC_REGADDR();
3830 	return readb((void __iomem *)reg_addr);
3831 }
3832 
3833 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3834 {
3835 	CALC_REGADDR();
3836 	writeb(value, (void __iomem *)reg_addr);
3837 }
3838 
3839 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3840 {
3841 	CALC_REGADDR();
3842 	return readw((void __iomem *)reg_addr);
3843 }
3844 
3845 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3846 {
3847 	CALC_REGADDR();
3848 	writew(value, (void __iomem *)reg_addr);
3849 }
3850 
3851 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3852 {
3853 	CALC_REGADDR();
3854 	return readl((void __iomem *)reg_addr);
3855 }
3856 
3857 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3858 {
3859 	CALC_REGADDR();
3860 	writel(value, (void __iomem *)reg_addr);
3861 }
3862 
3863 static void rdma_reset(struct slgt_info *info)
3864 {
3865 	unsigned int i;
3866 
3867 	/* set reset bit */
3868 	wr_reg32(info, RDCSR, BIT1);
3869 
3870 	/* wait for enable bit cleared */
3871 	for(i=0 ; i < 1000 ; i++)
3872 		if (!(rd_reg32(info, RDCSR) & BIT0))
3873 			break;
3874 }
3875 
3876 static void tdma_reset(struct slgt_info *info)
3877 {
3878 	unsigned int i;
3879 
3880 	/* set reset bit */
3881 	wr_reg32(info, TDCSR, BIT1);
3882 
3883 	/* wait for enable bit cleared */
3884 	for(i=0 ; i < 1000 ; i++)
3885 		if (!(rd_reg32(info, TDCSR) & BIT0))
3886 			break;
3887 }
3888 
3889 /*
3890  * enable internal loopback
3891  * TxCLK and RxCLK are generated from BRG
3892  * and TxD is looped back to RxD internally.
3893  */
3894 static void enable_loopback(struct slgt_info *info)
3895 {
3896 	/* SCR (serial control) BIT2=loopback enable */
3897 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3898 
3899 	if (info->params.mode != MGSL_MODE_ASYNC) {
3900 		/* CCR (clock control)
3901 		 * 07..05  tx clock source (010 = BRG)
3902 		 * 04..02  rx clock source (010 = BRG)
3903 		 * 01      auxclk enable   (0 = disable)
3904 		 * 00      BRG enable      (1 = enable)
3905 		 *
3906 		 * 0100 1001
3907 		 */
3908 		wr_reg8(info, CCR, 0x49);
3909 
3910 		/* set speed if available, otherwise use default */
3911 		if (info->params.clock_speed)
3912 			set_rate(info, info->params.clock_speed);
3913 		else
3914 			set_rate(info, 3686400);
3915 	}
3916 }
3917 
3918 /*
3919  *  set baud rate generator to specified rate
3920  */
3921 static void set_rate(struct slgt_info *info, u32 rate)
3922 {
3923 	unsigned int div;
3924 	unsigned int osc = info->base_clock;
3925 
3926 	/* div = osc/rate - 1
3927 	 *
3928 	 * Round div up if osc/rate is not integer to
3929 	 * force to next slowest rate.
3930 	 */
3931 
3932 	if (rate) {
3933 		div = osc/rate;
3934 		if (!(osc % rate) && div)
3935 			div--;
3936 		wr_reg16(info, BDR, (unsigned short)div);
3937 	}
3938 }
3939 
3940 static void rx_stop(struct slgt_info *info)
3941 {
3942 	unsigned short val;
3943 
3944 	/* disable and reset receiver */
3945 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3946 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3947 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3948 
3949 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3950 
3951 	/* clear pending rx interrupts */
3952 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3953 
3954 	rdma_reset(info);
3955 
3956 	info->rx_enabled = false;
3957 	info->rx_restart = false;
3958 }
3959 
3960 static void rx_start(struct slgt_info *info)
3961 {
3962 	unsigned short val;
3963 
3964 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3965 
3966 	/* clear pending rx overrun IRQ */
3967 	wr_reg16(info, SSR, IRQ_RXOVER);
3968 
3969 	/* reset and disable receiver */
3970 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3971 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3972 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3973 
3974 	rdma_reset(info);
3975 	reset_rbufs(info);
3976 
3977 	if (info->rx_pio) {
3978 		/* rx request when rx FIFO not empty */
3979 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3980 		slgt_irq_on(info, IRQ_RXDATA);
3981 		if (info->params.mode == MGSL_MODE_ASYNC) {
3982 			/* enable saving of rx status */
3983 			wr_reg32(info, RDCSR, BIT6);
3984 		}
3985 	} else {
3986 		/* rx request when rx FIFO half full */
3987 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3988 		/* set 1st descriptor address */
3989 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3990 
3991 		if (info->params.mode != MGSL_MODE_ASYNC) {
3992 			/* enable rx DMA and DMA interrupt */
3993 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3994 		} else {
3995 			/* enable saving of rx status, rx DMA and DMA interrupt */
3996 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3997 		}
3998 	}
3999 
4000 	slgt_irq_on(info, IRQ_RXOVER);
4001 
4002 	/* enable receiver */
4003 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4004 
4005 	info->rx_restart = false;
4006 	info->rx_enabled = true;
4007 }
4008 
4009 static void tx_start(struct slgt_info *info)
4010 {
4011 	if (!info->tx_enabled) {
4012 		wr_reg16(info, TCR,
4013 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4014 		info->tx_enabled = true;
4015 	}
4016 
4017 	if (desc_count(info->tbufs[info->tbuf_start])) {
4018 		info->drop_rts_on_tx_done = false;
4019 
4020 		if (info->params.mode != MGSL_MODE_ASYNC) {
4021 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4022 				get_signals(info);
4023 				if (!(info->signals & SerialSignal_RTS)) {
4024 					info->signals |= SerialSignal_RTS;
4025 					set_signals(info);
4026 					info->drop_rts_on_tx_done = true;
4027 				}
4028 			}
4029 
4030 			slgt_irq_off(info, IRQ_TXDATA);
4031 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4032 			/* clear tx idle and underrun status bits */
4033 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4034 		} else {
4035 			slgt_irq_off(info, IRQ_TXDATA);
4036 			slgt_irq_on(info, IRQ_TXIDLE);
4037 			/* clear tx idle status bit */
4038 			wr_reg16(info, SSR, IRQ_TXIDLE);
4039 		}
4040 		/* set 1st descriptor address and start DMA */
4041 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4042 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4043 		info->tx_active = true;
4044 	}
4045 }
4046 
4047 static void tx_stop(struct slgt_info *info)
4048 {
4049 	unsigned short val;
4050 
4051 	del_timer(&info->tx_timer);
4052 
4053 	tdma_reset(info);
4054 
4055 	/* reset and disable transmitter */
4056 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4057 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4058 
4059 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4060 
4061 	/* clear tx idle and underrun status bit */
4062 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4063 
4064 	reset_tbufs(info);
4065 
4066 	info->tx_enabled = false;
4067 	info->tx_active = false;
4068 }
4069 
4070 static void reset_port(struct slgt_info *info)
4071 {
4072 	if (!info->reg_addr)
4073 		return;
4074 
4075 	tx_stop(info);
4076 	rx_stop(info);
4077 
4078 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4079 	set_signals(info);
4080 
4081 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4082 }
4083 
4084 static void reset_adapter(struct slgt_info *info)
4085 {
4086 	int i;
4087 	for (i=0; i < info->port_count; ++i) {
4088 		if (info->port_array[i])
4089 			reset_port(info->port_array[i]);
4090 	}
4091 }
4092 
4093 static void async_mode(struct slgt_info *info)
4094 {
4095   	unsigned short val;
4096 
4097 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4098 	tx_stop(info);
4099 	rx_stop(info);
4100 
4101 	/* TCR (tx control)
4102 	 *
4103 	 * 15..13  mode, 010=async
4104 	 * 12..10  encoding, 000=NRZ
4105 	 * 09      parity enable
4106 	 * 08      1=odd parity, 0=even parity
4107 	 * 07      1=RTS driver control
4108 	 * 06      1=break enable
4109 	 * 05..04  character length
4110 	 *         00=5 bits
4111 	 *         01=6 bits
4112 	 *         10=7 bits
4113 	 *         11=8 bits
4114 	 * 03      0=1 stop bit, 1=2 stop bits
4115 	 * 02      reset
4116 	 * 01      enable
4117 	 * 00      auto-CTS enable
4118 	 */
4119 	val = 0x4000;
4120 
4121 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4122 		val |= BIT7;
4123 
4124 	if (info->params.parity != ASYNC_PARITY_NONE) {
4125 		val |= BIT9;
4126 		if (info->params.parity == ASYNC_PARITY_ODD)
4127 			val |= BIT8;
4128 	}
4129 
4130 	switch (info->params.data_bits)
4131 	{
4132 	case 6: val |= BIT4; break;
4133 	case 7: val |= BIT5; break;
4134 	case 8: val |= BIT5 + BIT4; break;
4135 	}
4136 
4137 	if (info->params.stop_bits != 1)
4138 		val |= BIT3;
4139 
4140 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4141 		val |= BIT0;
4142 
4143 	wr_reg16(info, TCR, val);
4144 
4145 	/* RCR (rx control)
4146 	 *
4147 	 * 15..13  mode, 010=async
4148 	 * 12..10  encoding, 000=NRZ
4149 	 * 09      parity enable
4150 	 * 08      1=odd parity, 0=even parity
4151 	 * 07..06  reserved, must be 0
4152 	 * 05..04  character length
4153 	 *         00=5 bits
4154 	 *         01=6 bits
4155 	 *         10=7 bits
4156 	 *         11=8 bits
4157 	 * 03      reserved, must be zero
4158 	 * 02      reset
4159 	 * 01      enable
4160 	 * 00      auto-DCD enable
4161 	 */
4162 	val = 0x4000;
4163 
4164 	if (info->params.parity != ASYNC_PARITY_NONE) {
4165 		val |= BIT9;
4166 		if (info->params.parity == ASYNC_PARITY_ODD)
4167 			val |= BIT8;
4168 	}
4169 
4170 	switch (info->params.data_bits)
4171 	{
4172 	case 6: val |= BIT4; break;
4173 	case 7: val |= BIT5; break;
4174 	case 8: val |= BIT5 + BIT4; break;
4175 	}
4176 
4177 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4178 		val |= BIT0;
4179 
4180 	wr_reg16(info, RCR, val);
4181 
4182 	/* CCR (clock control)
4183 	 *
4184 	 * 07..05  011 = tx clock source is BRG/16
4185 	 * 04..02  010 = rx clock source is BRG
4186 	 * 01      0 = auxclk disabled
4187 	 * 00      1 = BRG enabled
4188 	 *
4189 	 * 0110 1001
4190 	 */
4191 	wr_reg8(info, CCR, 0x69);
4192 
4193 	msc_set_vcr(info);
4194 
4195 	/* SCR (serial control)
4196 	 *
4197 	 * 15  1=tx req on FIFO half empty
4198 	 * 14  1=rx req on FIFO half full
4199 	 * 13  tx data  IRQ enable
4200 	 * 12  tx idle  IRQ enable
4201 	 * 11  rx break on IRQ enable
4202 	 * 10  rx data  IRQ enable
4203 	 * 09  rx break off IRQ enable
4204 	 * 08  overrun  IRQ enable
4205 	 * 07  DSR      IRQ enable
4206 	 * 06  CTS      IRQ enable
4207 	 * 05  DCD      IRQ enable
4208 	 * 04  RI       IRQ enable
4209 	 * 03  0=16x sampling, 1=8x sampling
4210 	 * 02  1=txd->rxd internal loopback enable
4211 	 * 01  reserved, must be zero
4212 	 * 00  1=master IRQ enable
4213 	 */
4214 	val = BIT15 + BIT14 + BIT0;
4215 	/* JCR[8] : 1 = x8 async mode feature available */
4216 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4217 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4218 	     (info->base_clock % (info->params.data_rate * 16)))) {
4219 		/* use 8x sampling */
4220 		val |= BIT3;
4221 		set_rate(info, info->params.data_rate * 8);
4222 	} else {
4223 		/* use 16x sampling */
4224 		set_rate(info, info->params.data_rate * 16);
4225 	}
4226 	wr_reg16(info, SCR, val);
4227 
4228 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4229 
4230 	if (info->params.loopback)
4231 		enable_loopback(info);
4232 }
4233 
4234 static void sync_mode(struct slgt_info *info)
4235 {
4236 	unsigned short val;
4237 
4238 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4239 	tx_stop(info);
4240 	rx_stop(info);
4241 
4242 	/* TCR (tx control)
4243 	 *
4244 	 * 15..13  mode
4245 	 *         000=HDLC/SDLC
4246 	 *         001=raw bit synchronous
4247 	 *         010=asynchronous/isochronous
4248 	 *         011=monosync byte synchronous
4249 	 *         100=bisync byte synchronous
4250 	 *         101=xsync byte synchronous
4251 	 * 12..10  encoding
4252 	 * 09      CRC enable
4253 	 * 08      CRC32
4254 	 * 07      1=RTS driver control
4255 	 * 06      preamble enable
4256 	 * 05..04  preamble length
4257 	 * 03      share open/close flag
4258 	 * 02      reset
4259 	 * 01      enable
4260 	 * 00      auto-CTS enable
4261 	 */
4262 	val = BIT2;
4263 
4264 	switch(info->params.mode) {
4265 	case MGSL_MODE_XSYNC:
4266 		val |= BIT15 + BIT13;
4267 		break;
4268 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4269 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4270 	case MGSL_MODE_RAW:      val |= BIT13; break;
4271 	}
4272 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4273 		val |= BIT7;
4274 
4275 	switch(info->params.encoding)
4276 	{
4277 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4278 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4279 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4280 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4281 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4282 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4283 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4284 	}
4285 
4286 	switch (info->params.crc_type & HDLC_CRC_MASK)
4287 	{
4288 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4289 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4290 	}
4291 
4292 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4293 		val |= BIT6;
4294 
4295 	switch (info->params.preamble_length)
4296 	{
4297 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4298 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4299 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4300 	}
4301 
4302 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4303 		val |= BIT0;
4304 
4305 	wr_reg16(info, TCR, val);
4306 
4307 	/* TPR (transmit preamble) */
4308 
4309 	switch (info->params.preamble)
4310 	{
4311 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4312 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4313 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4314 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4315 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4316 	default:                          val = 0x7e; break;
4317 	}
4318 	wr_reg8(info, TPR, (unsigned char)val);
4319 
4320 	/* RCR (rx control)
4321 	 *
4322 	 * 15..13  mode
4323 	 *         000=HDLC/SDLC
4324 	 *         001=raw bit synchronous
4325 	 *         010=asynchronous/isochronous
4326 	 *         011=monosync byte synchronous
4327 	 *         100=bisync byte synchronous
4328 	 *         101=xsync byte synchronous
4329 	 * 12..10  encoding
4330 	 * 09      CRC enable
4331 	 * 08      CRC32
4332 	 * 07..03  reserved, must be 0
4333 	 * 02      reset
4334 	 * 01      enable
4335 	 * 00      auto-DCD enable
4336 	 */
4337 	val = 0;
4338 
4339 	switch(info->params.mode) {
4340 	case MGSL_MODE_XSYNC:
4341 		val |= BIT15 + BIT13;
4342 		break;
4343 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4344 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4345 	case MGSL_MODE_RAW:      val |= BIT13; break;
4346 	}
4347 
4348 	switch(info->params.encoding)
4349 	{
4350 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4351 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4352 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4353 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4354 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4355 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4356 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4357 	}
4358 
4359 	switch (info->params.crc_type & HDLC_CRC_MASK)
4360 	{
4361 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4362 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4363 	}
4364 
4365 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4366 		val |= BIT0;
4367 
4368 	wr_reg16(info, RCR, val);
4369 
4370 	/* CCR (clock control)
4371 	 *
4372 	 * 07..05  tx clock source
4373 	 * 04..02  rx clock source
4374 	 * 01      auxclk enable
4375 	 * 00      BRG enable
4376 	 */
4377 	val = 0;
4378 
4379 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4380 	{
4381 		// when RxC source is DPLL, BRG generates 16X DPLL
4382 		// reference clock, so take TxC from BRG/16 to get
4383 		// transmit clock at actual data rate
4384 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4385 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4386 		else
4387 			val |= BIT6;	/* 010, txclk = BRG */
4388 	}
4389 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4390 		val |= BIT7;	/* 100, txclk = DPLL Input */
4391 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4392 		val |= BIT5;	/* 001, txclk = RXC Input */
4393 
4394 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4395 		val |= BIT3;	/* 010, rxclk = BRG */
4396 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4397 		val |= BIT4;	/* 100, rxclk = DPLL */
4398 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4399 		val |= BIT2;	/* 001, rxclk = TXC Input */
4400 
4401 	if (info->params.clock_speed)
4402 		val |= BIT1 + BIT0;
4403 
4404 	wr_reg8(info, CCR, (unsigned char)val);
4405 
4406 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4407 	{
4408 		// program DPLL mode
4409 		switch(info->params.encoding)
4410 		{
4411 		case HDLC_ENCODING_BIPHASE_MARK:
4412 		case HDLC_ENCODING_BIPHASE_SPACE:
4413 			val = BIT7; break;
4414 		case HDLC_ENCODING_BIPHASE_LEVEL:
4415 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4416 			val = BIT7 + BIT6; break;
4417 		default: val = BIT6;	// NRZ encodings
4418 		}
4419 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4420 
4421 		// DPLL requires a 16X reference clock from BRG
4422 		set_rate(info, info->params.clock_speed * 16);
4423 	}
4424 	else
4425 		set_rate(info, info->params.clock_speed);
4426 
4427 	tx_set_idle(info);
4428 
4429 	msc_set_vcr(info);
4430 
4431 	/* SCR (serial control)
4432 	 *
4433 	 * 15  1=tx req on FIFO half empty
4434 	 * 14  1=rx req on FIFO half full
4435 	 * 13  tx data  IRQ enable
4436 	 * 12  tx idle  IRQ enable
4437 	 * 11  underrun IRQ enable
4438 	 * 10  rx data  IRQ enable
4439 	 * 09  rx idle  IRQ enable
4440 	 * 08  overrun  IRQ enable
4441 	 * 07  DSR      IRQ enable
4442 	 * 06  CTS      IRQ enable
4443 	 * 05  DCD      IRQ enable
4444 	 * 04  RI       IRQ enable
4445 	 * 03  reserved, must be zero
4446 	 * 02  1=txd->rxd internal loopback enable
4447 	 * 01  reserved, must be zero
4448 	 * 00  1=master IRQ enable
4449 	 */
4450 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4451 
4452 	if (info->params.loopback)
4453 		enable_loopback(info);
4454 }
4455 
4456 /*
4457  *  set transmit idle mode
4458  */
4459 static void tx_set_idle(struct slgt_info *info)
4460 {
4461 	unsigned char val;
4462 	unsigned short tcr;
4463 
4464 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4465 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4466 	 */
4467 	tcr = rd_reg16(info, TCR);
4468 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4469 		/* disable preamble, set idle size to 16 bits */
4470 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4471 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4472 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4473 	} else if (!(tcr & BIT6)) {
4474 		/* preamble is disabled, set idle size to 8 bits */
4475 		tcr &= ~(BIT5 + BIT4);
4476 	}
4477 	wr_reg16(info, TCR, tcr);
4478 
4479 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4480 		/* LSB of custom tx idle specified in tx idle register */
4481 		val = (unsigned char)(info->idle_mode & 0xff);
4482 	} else {
4483 		/* standard 8 bit idle patterns */
4484 		switch(info->idle_mode)
4485 		{
4486 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4487 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4488 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4489 		case HDLC_TXIDLE_ZEROS:
4490 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4491 		default:                         val = 0xff;
4492 		}
4493 	}
4494 
4495 	wr_reg8(info, TIR, val);
4496 }
4497 
4498 /*
4499  * get state of V24 status (input) signals
4500  */
4501 static void get_signals(struct slgt_info *info)
4502 {
4503 	unsigned short status = rd_reg16(info, SSR);
4504 
4505 	/* clear all serial signals except RTS and DTR */
4506 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4507 
4508 	if (status & BIT3)
4509 		info->signals |= SerialSignal_DSR;
4510 	if (status & BIT2)
4511 		info->signals |= SerialSignal_CTS;
4512 	if (status & BIT1)
4513 		info->signals |= SerialSignal_DCD;
4514 	if (status & BIT0)
4515 		info->signals |= SerialSignal_RI;
4516 }
4517 
4518 /*
4519  * set V.24 Control Register based on current configuration
4520  */
4521 static void msc_set_vcr(struct slgt_info *info)
4522 {
4523 	unsigned char val = 0;
4524 
4525 	/* VCR (V.24 control)
4526 	 *
4527 	 * 07..04  serial IF select
4528 	 * 03      DTR
4529 	 * 02      RTS
4530 	 * 01      LL
4531 	 * 00      RL
4532 	 */
4533 
4534 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4535 	{
4536 	case MGSL_INTERFACE_RS232:
4537 		val |= BIT5; /* 0010 */
4538 		break;
4539 	case MGSL_INTERFACE_V35:
4540 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4541 		break;
4542 	case MGSL_INTERFACE_RS422:
4543 		val |= BIT6; /* 0100 */
4544 		break;
4545 	}
4546 
4547 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4548 		val |= BIT4;
4549 	if (info->signals & SerialSignal_DTR)
4550 		val |= BIT3;
4551 	if (info->signals & SerialSignal_RTS)
4552 		val |= BIT2;
4553 	if (info->if_mode & MGSL_INTERFACE_LL)
4554 		val |= BIT1;
4555 	if (info->if_mode & MGSL_INTERFACE_RL)
4556 		val |= BIT0;
4557 	wr_reg8(info, VCR, val);
4558 }
4559 
4560 /*
4561  * set state of V24 control (output) signals
4562  */
4563 static void set_signals(struct slgt_info *info)
4564 {
4565 	unsigned char val = rd_reg8(info, VCR);
4566 	if (info->signals & SerialSignal_DTR)
4567 		val |= BIT3;
4568 	else
4569 		val &= ~BIT3;
4570 	if (info->signals & SerialSignal_RTS)
4571 		val |= BIT2;
4572 	else
4573 		val &= ~BIT2;
4574 	wr_reg8(info, VCR, val);
4575 }
4576 
4577 /*
4578  * free range of receive DMA buffers (i to last)
4579  */
4580 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4581 {
4582 	int done = 0;
4583 
4584 	while(!done) {
4585 		/* reset current buffer for reuse */
4586 		info->rbufs[i].status = 0;
4587 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4588 		if (i == last)
4589 			done = 1;
4590 		if (++i == info->rbuf_count)
4591 			i = 0;
4592 	}
4593 	info->rbuf_current = i;
4594 }
4595 
4596 /*
4597  * mark all receive DMA buffers as free
4598  */
4599 static void reset_rbufs(struct slgt_info *info)
4600 {
4601 	free_rbufs(info, 0, info->rbuf_count - 1);
4602 	info->rbuf_fill_index = 0;
4603 	info->rbuf_fill_count = 0;
4604 }
4605 
4606 /*
4607  * pass receive HDLC frame to upper layer
4608  *
4609  * return true if frame available, otherwise false
4610  */
4611 static bool rx_get_frame(struct slgt_info *info)
4612 {
4613 	unsigned int start, end;
4614 	unsigned short status;
4615 	unsigned int framesize = 0;
4616 	unsigned long flags;
4617 	struct tty_struct *tty = info->port.tty;
4618 	unsigned char addr_field = 0xff;
4619 	unsigned int crc_size = 0;
4620 
4621 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4622 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4623 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4624 	}
4625 
4626 check_again:
4627 
4628 	framesize = 0;
4629 	addr_field = 0xff;
4630 	start = end = info->rbuf_current;
4631 
4632 	for (;;) {
4633 		if (!desc_complete(info->rbufs[end]))
4634 			goto cleanup;
4635 
4636 		if (framesize == 0 && info->params.addr_filter != 0xff)
4637 			addr_field = info->rbufs[end].buf[0];
4638 
4639 		framesize += desc_count(info->rbufs[end]);
4640 
4641 		if (desc_eof(info->rbufs[end]))
4642 			break;
4643 
4644 		if (++end == info->rbuf_count)
4645 			end = 0;
4646 
4647 		if (end == info->rbuf_current) {
4648 			if (info->rx_enabled){
4649 				spin_lock_irqsave(&info->lock,flags);
4650 				rx_start(info);
4651 				spin_unlock_irqrestore(&info->lock,flags);
4652 			}
4653 			goto cleanup;
4654 		}
4655 	}
4656 
4657 	/* status
4658 	 *
4659 	 * 15      buffer complete
4660 	 * 14..06  reserved
4661 	 * 05..04  residue
4662 	 * 02      eof (end of frame)
4663 	 * 01      CRC error
4664 	 * 00      abort
4665 	 */
4666 	status = desc_status(info->rbufs[end]);
4667 
4668 	/* ignore CRC bit if not using CRC (bit is undefined) */
4669 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4670 		status &= ~BIT1;
4671 
4672 	if (framesize == 0 ||
4673 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4674 		free_rbufs(info, start, end);
4675 		goto check_again;
4676 	}
4677 
4678 	if (framesize < (2 + crc_size) || status & BIT0) {
4679 		info->icount.rxshort++;
4680 		framesize = 0;
4681 	} else if (status & BIT1) {
4682 		info->icount.rxcrc++;
4683 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4684 			framesize = 0;
4685 	}
4686 
4687 #if SYNCLINK_GENERIC_HDLC
4688 	if (framesize == 0) {
4689 		info->netdev->stats.rx_errors++;
4690 		info->netdev->stats.rx_frame_errors++;
4691 	}
4692 #endif
4693 
4694 	DBGBH(("%s rx frame status=%04X size=%d\n",
4695 		info->device_name, status, framesize));
4696 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4697 
4698 	if (framesize) {
4699 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4700 			framesize -= crc_size;
4701 			crc_size = 0;
4702 		}
4703 
4704 		if (framesize > info->max_frame_size + crc_size)
4705 			info->icount.rxlong++;
4706 		else {
4707 			/* copy dma buffer(s) to contiguous temp buffer */
4708 			int copy_count = framesize;
4709 			int i = start;
4710 			unsigned char *p = info->tmp_rbuf;
4711 			info->tmp_rbuf_count = framesize;
4712 
4713 			info->icount.rxok++;
4714 
4715 			while(copy_count) {
4716 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4717 				memcpy(p, info->rbufs[i].buf, partial_count);
4718 				p += partial_count;
4719 				copy_count -= partial_count;
4720 				if (++i == info->rbuf_count)
4721 					i = 0;
4722 			}
4723 
4724 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4725 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4726 				framesize++;
4727 			}
4728 
4729 #if SYNCLINK_GENERIC_HDLC
4730 			if (info->netcount)
4731 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4732 			else
4733 #endif
4734 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4735 		}
4736 	}
4737 	free_rbufs(info, start, end);
4738 	return true;
4739 
4740 cleanup:
4741 	return false;
4742 }
4743 
4744 /*
4745  * pass receive buffer (RAW synchronous mode) to tty layer
4746  * return true if buffer available, otherwise false
4747  */
4748 static bool rx_get_buf(struct slgt_info *info)
4749 {
4750 	unsigned int i = info->rbuf_current;
4751 	unsigned int count;
4752 
4753 	if (!desc_complete(info->rbufs[i]))
4754 		return false;
4755 	count = desc_count(info->rbufs[i]);
4756 	switch(info->params.mode) {
4757 	case MGSL_MODE_MONOSYNC:
4758 	case MGSL_MODE_BISYNC:
4759 	case MGSL_MODE_XSYNC:
4760 		/* ignore residue in byte synchronous modes */
4761 		if (desc_residue(info->rbufs[i]))
4762 			count--;
4763 		break;
4764 	}
4765 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4766 	DBGINFO(("rx_get_buf size=%d\n", count));
4767 	if (count)
4768 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4769 				  info->flag_buf, count);
4770 	free_rbufs(info, i, i);
4771 	return true;
4772 }
4773 
4774 static void reset_tbufs(struct slgt_info *info)
4775 {
4776 	unsigned int i;
4777 	info->tbuf_current = 0;
4778 	for (i=0 ; i < info->tbuf_count ; i++) {
4779 		info->tbufs[i].status = 0;
4780 		info->tbufs[i].count  = 0;
4781 	}
4782 }
4783 
4784 /*
4785  * return number of free transmit DMA buffers
4786  */
4787 static unsigned int free_tbuf_count(struct slgt_info *info)
4788 {
4789 	unsigned int count = 0;
4790 	unsigned int i = info->tbuf_current;
4791 
4792 	do
4793 	{
4794 		if (desc_count(info->tbufs[i]))
4795 			break; /* buffer in use */
4796 		++count;
4797 		if (++i == info->tbuf_count)
4798 			i=0;
4799 	} while (i != info->tbuf_current);
4800 
4801 	/* if tx DMA active, last zero count buffer is in use */
4802 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4803 		--count;
4804 
4805 	return count;
4806 }
4807 
4808 /*
4809  * return number of bytes in unsent transmit DMA buffers
4810  * and the serial controller tx FIFO
4811  */
4812 static unsigned int tbuf_bytes(struct slgt_info *info)
4813 {
4814 	unsigned int total_count = 0;
4815 	unsigned int i = info->tbuf_current;
4816 	unsigned int reg_value;
4817 	unsigned int count;
4818 	unsigned int active_buf_count = 0;
4819 
4820 	/*
4821 	 * Add descriptor counts for all tx DMA buffers.
4822 	 * If count is zero (cleared by DMA controller after read),
4823 	 * the buffer is complete or is actively being read from.
4824 	 *
4825 	 * Record buf_count of last buffer with zero count starting
4826 	 * from current ring position. buf_count is mirror
4827 	 * copy of count and is not cleared by serial controller.
4828 	 * If DMA controller is active, that buffer is actively
4829 	 * being read so add to total.
4830 	 */
4831 	do {
4832 		count = desc_count(info->tbufs[i]);
4833 		if (count)
4834 			total_count += count;
4835 		else if (!total_count)
4836 			active_buf_count = info->tbufs[i].buf_count;
4837 		if (++i == info->tbuf_count)
4838 			i = 0;
4839 	} while (i != info->tbuf_current);
4840 
4841 	/* read tx DMA status register */
4842 	reg_value = rd_reg32(info, TDCSR);
4843 
4844 	/* if tx DMA active, last zero count buffer is in use */
4845 	if (reg_value & BIT0)
4846 		total_count += active_buf_count;
4847 
4848 	/* add tx FIFO count = reg_value[15..8] */
4849 	total_count += (reg_value >> 8) & 0xff;
4850 
4851 	/* if transmitter active add one byte for shift register */
4852 	if (info->tx_active)
4853 		total_count++;
4854 
4855 	return total_count;
4856 }
4857 
4858 /*
4859  * load data into transmit DMA buffer ring and start transmitter if needed
4860  * return true if data accepted, otherwise false (buffers full)
4861  */
4862 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4863 {
4864 	unsigned short count;
4865 	unsigned int i;
4866 	struct slgt_desc *d;
4867 
4868 	/* check required buffer space */
4869 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4870 		return false;
4871 
4872 	DBGDATA(info, buf, size, "tx");
4873 
4874 	/*
4875 	 * copy data to one or more DMA buffers in circular ring
4876 	 * tbuf_start   = first buffer for this data
4877 	 * tbuf_current = next free buffer
4878 	 *
4879 	 * Copy all data before making data visible to DMA controller by
4880 	 * setting descriptor count of the first buffer.
4881 	 * This prevents an active DMA controller from reading the first DMA
4882 	 * buffers of a frame and stopping before the final buffers are filled.
4883 	 */
4884 
4885 	info->tbuf_start = i = info->tbuf_current;
4886 
4887 	while (size) {
4888 		d = &info->tbufs[i];
4889 
4890 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4891 		memcpy(d->buf, buf, count);
4892 
4893 		size -= count;
4894 		buf  += count;
4895 
4896 		/*
4897 		 * set EOF bit for last buffer of HDLC frame or
4898 		 * for every buffer in raw mode
4899 		 */
4900 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4901 		    info->params.mode == MGSL_MODE_RAW)
4902 			set_desc_eof(*d, 1);
4903 		else
4904 			set_desc_eof(*d, 0);
4905 
4906 		/* set descriptor count for all but first buffer */
4907 		if (i != info->tbuf_start)
4908 			set_desc_count(*d, count);
4909 		d->buf_count = count;
4910 
4911 		if (++i == info->tbuf_count)
4912 			i = 0;
4913 	}
4914 
4915 	info->tbuf_current = i;
4916 
4917 	/* set first buffer count to make new data visible to DMA controller */
4918 	d = &info->tbufs[info->tbuf_start];
4919 	set_desc_count(*d, d->buf_count);
4920 
4921 	/* start transmitter if needed and update transmit timeout */
4922 	if (!info->tx_active)
4923 		tx_start(info);
4924 	update_tx_timer(info);
4925 
4926 	return true;
4927 }
4928 
4929 static int register_test(struct slgt_info *info)
4930 {
4931 	static unsigned short patterns[] =
4932 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4933 	static unsigned int count = ARRAY_SIZE(patterns);
4934 	unsigned int i;
4935 	int rc = 0;
4936 
4937 	for (i=0 ; i < count ; i++) {
4938 		wr_reg16(info, TIR, patterns[i]);
4939 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4940 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4941 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4942 			rc = -ENODEV;
4943 			break;
4944 		}
4945 	}
4946 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4947 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4948 	return rc;
4949 }
4950 
4951 static int irq_test(struct slgt_info *info)
4952 {
4953 	unsigned long timeout;
4954 	unsigned long flags;
4955 	struct tty_struct *oldtty = info->port.tty;
4956 	u32 speed = info->params.data_rate;
4957 
4958 	info->params.data_rate = 921600;
4959 	info->port.tty = NULL;
4960 
4961 	spin_lock_irqsave(&info->lock, flags);
4962 	async_mode(info);
4963 	slgt_irq_on(info, IRQ_TXIDLE);
4964 
4965 	/* enable transmitter */
4966 	wr_reg16(info, TCR,
4967 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4968 
4969 	/* write one byte and wait for tx idle */
4970 	wr_reg16(info, TDR, 0);
4971 
4972 	/* assume failure */
4973 	info->init_error = DiagStatus_IrqFailure;
4974 	info->irq_occurred = false;
4975 
4976 	spin_unlock_irqrestore(&info->lock, flags);
4977 
4978 	timeout=100;
4979 	while(timeout-- && !info->irq_occurred)
4980 		msleep_interruptible(10);
4981 
4982 	spin_lock_irqsave(&info->lock,flags);
4983 	reset_port(info);
4984 	spin_unlock_irqrestore(&info->lock,flags);
4985 
4986 	info->params.data_rate = speed;
4987 	info->port.tty = oldtty;
4988 
4989 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4990 	return info->irq_occurred ? 0 : -ENODEV;
4991 }
4992 
4993 static int loopback_test_rx(struct slgt_info *info)
4994 {
4995 	unsigned char *src, *dest;
4996 	int count;
4997 
4998 	if (desc_complete(info->rbufs[0])) {
4999 		count = desc_count(info->rbufs[0]);
5000 		src   = info->rbufs[0].buf;
5001 		dest  = info->tmp_rbuf;
5002 
5003 		for( ; count ; count-=2, src+=2) {
5004 			/* src=data byte (src+1)=status byte */
5005 			if (!(*(src+1) & (BIT9 + BIT8))) {
5006 				*dest = *src;
5007 				dest++;
5008 				info->tmp_rbuf_count++;
5009 			}
5010 		}
5011 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5012 		return 1;
5013 	}
5014 	return 0;
5015 }
5016 
5017 static int loopback_test(struct slgt_info *info)
5018 {
5019 #define TESTFRAMESIZE 20
5020 
5021 	unsigned long timeout;
5022 	u16 count = TESTFRAMESIZE;
5023 	unsigned char buf[TESTFRAMESIZE];
5024 	int rc = -ENODEV;
5025 	unsigned long flags;
5026 
5027 	struct tty_struct *oldtty = info->port.tty;
5028 	MGSL_PARAMS params;
5029 
5030 	memcpy(&params, &info->params, sizeof(params));
5031 
5032 	info->params.mode = MGSL_MODE_ASYNC;
5033 	info->params.data_rate = 921600;
5034 	info->params.loopback = 1;
5035 	info->port.tty = NULL;
5036 
5037 	/* build and send transmit frame */
5038 	for (count = 0; count < TESTFRAMESIZE; ++count)
5039 		buf[count] = (unsigned char)count;
5040 
5041 	info->tmp_rbuf_count = 0;
5042 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5043 
5044 	/* program hardware for HDLC and enabled receiver */
5045 	spin_lock_irqsave(&info->lock,flags);
5046 	async_mode(info);
5047 	rx_start(info);
5048 	tx_load(info, buf, count);
5049 	spin_unlock_irqrestore(&info->lock, flags);
5050 
5051 	/* wait for receive complete */
5052 	for (timeout = 100; timeout; --timeout) {
5053 		msleep_interruptible(10);
5054 		if (loopback_test_rx(info)) {
5055 			rc = 0;
5056 			break;
5057 		}
5058 	}
5059 
5060 	/* verify received frame length and contents */
5061 	if (!rc && (info->tmp_rbuf_count != count ||
5062 		  memcmp(buf, info->tmp_rbuf, count))) {
5063 		rc = -ENODEV;
5064 	}
5065 
5066 	spin_lock_irqsave(&info->lock,flags);
5067 	reset_adapter(info);
5068 	spin_unlock_irqrestore(&info->lock,flags);
5069 
5070 	memcpy(&info->params, &params, sizeof(info->params));
5071 	info->port.tty = oldtty;
5072 
5073 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5074 	return rc;
5075 }
5076 
5077 static int adapter_test(struct slgt_info *info)
5078 {
5079 	DBGINFO(("testing %s\n", info->device_name));
5080 	if (register_test(info) < 0) {
5081 		printk("register test failure %s addr=%08X\n",
5082 			info->device_name, info->phys_reg_addr);
5083 	} else if (irq_test(info) < 0) {
5084 		printk("IRQ test failure %s IRQ=%d\n",
5085 			info->device_name, info->irq_level);
5086 	} else if (loopback_test(info) < 0) {
5087 		printk("loopback test failure %s\n", info->device_name);
5088 	}
5089 	return info->init_error;
5090 }
5091 
5092 /*
5093  * transmit timeout handler
5094  */
5095 static void tx_timeout(struct timer_list *t)
5096 {
5097 	struct slgt_info *info = from_timer(info, t, tx_timer);
5098 	unsigned long flags;
5099 
5100 	DBGINFO(("%s tx_timeout\n", info->device_name));
5101 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5102 		info->icount.txtimeout++;
5103 	}
5104 	spin_lock_irqsave(&info->lock,flags);
5105 	tx_stop(info);
5106 	spin_unlock_irqrestore(&info->lock,flags);
5107 
5108 #if SYNCLINK_GENERIC_HDLC
5109 	if (info->netcount)
5110 		hdlcdev_tx_done(info);
5111 	else
5112 #endif
5113 		bh_transmit(info);
5114 }
5115 
5116 /*
5117  * receive buffer polling timer
5118  */
5119 static void rx_timeout(struct timer_list *t)
5120 {
5121 	struct slgt_info *info = from_timer(info, t, rx_timer);
5122 	unsigned long flags;
5123 
5124 	DBGINFO(("%s rx_timeout\n", info->device_name));
5125 	spin_lock_irqsave(&info->lock, flags);
5126 	info->pending_bh |= BH_RECEIVE;
5127 	spin_unlock_irqrestore(&info->lock, flags);
5128 	bh_handler(&info->task);
5129 }
5130 
5131