xref: /openbmc/linux/drivers/tty/synclink_gt.c (revision 11a163f2)
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  */
1682 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1683 {
1684 	struct slgt_info *info = dev_to_port(dev);
1685 	unsigned long flags;
1686 
1687 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1688 
1689 	dev->stats.tx_errors++;
1690 	dev->stats.tx_aborted_errors++;
1691 
1692 	spin_lock_irqsave(&info->lock,flags);
1693 	tx_stop(info);
1694 	spin_unlock_irqrestore(&info->lock,flags);
1695 
1696 	netif_wake_queue(dev);
1697 }
1698 
1699 /**
1700  * hdlcdev_tx_done - called by device driver when transmit completes
1701  * @info: pointer to device instance information
1702  *
1703  * Reenable network layer transmit if stopped.
1704  */
1705 static void hdlcdev_tx_done(struct slgt_info *info)
1706 {
1707 	if (netif_queue_stopped(info->netdev))
1708 		netif_wake_queue(info->netdev);
1709 }
1710 
1711 /**
1712  * hdlcdev_rx - called by device driver when frame received
1713  * @info: pointer to device instance information
1714  * @buf:  pointer to buffer contianing frame data
1715  * @size: count of data bytes in buf
1716  *
1717  * Pass frame to network layer.
1718  */
1719 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1720 {
1721 	struct sk_buff *skb = dev_alloc_skb(size);
1722 	struct net_device *dev = info->netdev;
1723 
1724 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1725 
1726 	if (skb == NULL) {
1727 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1728 		dev->stats.rx_dropped++;
1729 		return;
1730 	}
1731 
1732 	skb_put_data(skb, buf, size);
1733 
1734 	skb->protocol = hdlc_type_trans(skb, dev);
1735 
1736 	dev->stats.rx_packets++;
1737 	dev->stats.rx_bytes += size;
1738 
1739 	netif_rx(skb);
1740 }
1741 
1742 static const struct net_device_ops hdlcdev_ops = {
1743 	.ndo_open       = hdlcdev_open,
1744 	.ndo_stop       = hdlcdev_close,
1745 	.ndo_start_xmit = hdlc_start_xmit,
1746 	.ndo_do_ioctl   = hdlcdev_ioctl,
1747 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1748 };
1749 
1750 /**
1751  * hdlcdev_init - called by device driver when adding device instance
1752  * @info: pointer to device instance information
1753  *
1754  * Do generic HDLC initialization.
1755  *
1756  * Return: 0 if success, otherwise error code
1757  */
1758 static int hdlcdev_init(struct slgt_info *info)
1759 {
1760 	int rc;
1761 	struct net_device *dev;
1762 	hdlc_device *hdlc;
1763 
1764 	/* allocate and initialize network and HDLC layer objects */
1765 
1766 	dev = alloc_hdlcdev(info);
1767 	if (!dev) {
1768 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1769 		return -ENOMEM;
1770 	}
1771 
1772 	/* for network layer reporting purposes only */
1773 	dev->mem_start = info->phys_reg_addr;
1774 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1775 	dev->irq       = info->irq_level;
1776 
1777 	/* network layer callbacks and settings */
1778 	dev->netdev_ops	    = &hdlcdev_ops;
1779 	dev->watchdog_timeo = 10 * HZ;
1780 	dev->tx_queue_len   = 50;
1781 
1782 	/* generic HDLC layer callbacks and settings */
1783 	hdlc         = dev_to_hdlc(dev);
1784 	hdlc->attach = hdlcdev_attach;
1785 	hdlc->xmit   = hdlcdev_xmit;
1786 
1787 	/* register objects with HDLC layer */
1788 	rc = register_hdlc_device(dev);
1789 	if (rc) {
1790 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1791 		free_netdev(dev);
1792 		return rc;
1793 	}
1794 
1795 	info->netdev = dev;
1796 	return 0;
1797 }
1798 
1799 /**
1800  * hdlcdev_exit - called by device driver when removing device instance
1801  * @info: pointer to device instance information
1802  *
1803  * Do generic HDLC cleanup.
1804  */
1805 static void hdlcdev_exit(struct slgt_info *info)
1806 {
1807 	unregister_hdlc_device(info->netdev);
1808 	free_netdev(info->netdev);
1809 	info->netdev = NULL;
1810 }
1811 
1812 #endif /* ifdef CONFIG_HDLC */
1813 
1814 /*
1815  * get async data from rx DMA buffers
1816  */
1817 static void rx_async(struct slgt_info *info)
1818 {
1819  	struct mgsl_icount *icount = &info->icount;
1820 	unsigned int start, end;
1821 	unsigned char *p;
1822 	unsigned char status;
1823 	struct slgt_desc *bufs = info->rbufs;
1824 	int i, count;
1825 	int chars = 0;
1826 	int stat;
1827 	unsigned char ch;
1828 
1829 	start = end = info->rbuf_current;
1830 
1831 	while(desc_complete(bufs[end])) {
1832 		count = desc_count(bufs[end]) - info->rbuf_index;
1833 		p     = bufs[end].buf + info->rbuf_index;
1834 
1835 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1836 		DBGDATA(info, p, count, "rx");
1837 
1838 		for(i=0 ; i < count; i+=2, p+=2) {
1839 			ch = *p;
1840 			icount->rx++;
1841 
1842 			stat = 0;
1843 
1844 			status = *(p + 1) & (BIT1 + BIT0);
1845 			if (status) {
1846 				if (status & BIT1)
1847 					icount->parity++;
1848 				else if (status & BIT0)
1849 					icount->frame++;
1850 				/* discard char if tty control flags say so */
1851 				if (status & info->ignore_status_mask)
1852 					continue;
1853 				if (status & BIT1)
1854 					stat = TTY_PARITY;
1855 				else if (status & BIT0)
1856 					stat = TTY_FRAME;
1857 			}
1858 			tty_insert_flip_char(&info->port, ch, stat);
1859 			chars++;
1860 		}
1861 
1862 		if (i < count) {
1863 			/* receive buffer not completed */
1864 			info->rbuf_index += i;
1865 			mod_timer(&info->rx_timer, jiffies + 1);
1866 			break;
1867 		}
1868 
1869 		info->rbuf_index = 0;
1870 		free_rbufs(info, end, end);
1871 
1872 		if (++end == info->rbuf_count)
1873 			end = 0;
1874 
1875 		/* if entire list searched then no frame available */
1876 		if (end == start)
1877 			break;
1878 	}
1879 
1880 	if (chars)
1881 		tty_flip_buffer_push(&info->port);
1882 }
1883 
1884 /*
1885  * return next bottom half action to perform
1886  */
1887 static int bh_action(struct slgt_info *info)
1888 {
1889 	unsigned long flags;
1890 	int rc;
1891 
1892 	spin_lock_irqsave(&info->lock,flags);
1893 
1894 	if (info->pending_bh & BH_RECEIVE) {
1895 		info->pending_bh &= ~BH_RECEIVE;
1896 		rc = BH_RECEIVE;
1897 	} else if (info->pending_bh & BH_TRANSMIT) {
1898 		info->pending_bh &= ~BH_TRANSMIT;
1899 		rc = BH_TRANSMIT;
1900 	} else if (info->pending_bh & BH_STATUS) {
1901 		info->pending_bh &= ~BH_STATUS;
1902 		rc = BH_STATUS;
1903 	} else {
1904 		/* Mark BH routine as complete */
1905 		info->bh_running = false;
1906 		info->bh_requested = false;
1907 		rc = 0;
1908 	}
1909 
1910 	spin_unlock_irqrestore(&info->lock,flags);
1911 
1912 	return rc;
1913 }
1914 
1915 /*
1916  * perform bottom half processing
1917  */
1918 static void bh_handler(struct work_struct *work)
1919 {
1920 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1921 	int action;
1922 
1923 	info->bh_running = true;
1924 
1925 	while((action = bh_action(info))) {
1926 		switch (action) {
1927 		case BH_RECEIVE:
1928 			DBGBH(("%s bh receive\n", info->device_name));
1929 			switch(info->params.mode) {
1930 			case MGSL_MODE_ASYNC:
1931 				rx_async(info);
1932 				break;
1933 			case MGSL_MODE_HDLC:
1934 				while(rx_get_frame(info));
1935 				break;
1936 			case MGSL_MODE_RAW:
1937 			case MGSL_MODE_MONOSYNC:
1938 			case MGSL_MODE_BISYNC:
1939 			case MGSL_MODE_XSYNC:
1940 				while(rx_get_buf(info));
1941 				break;
1942 			}
1943 			/* restart receiver if rx DMA buffers exhausted */
1944 			if (info->rx_restart)
1945 				rx_start(info);
1946 			break;
1947 		case BH_TRANSMIT:
1948 			bh_transmit(info);
1949 			break;
1950 		case BH_STATUS:
1951 			DBGBH(("%s bh status\n", info->device_name));
1952 			info->ri_chkcount = 0;
1953 			info->dsr_chkcount = 0;
1954 			info->dcd_chkcount = 0;
1955 			info->cts_chkcount = 0;
1956 			break;
1957 		default:
1958 			DBGBH(("%s unknown action\n", info->device_name));
1959 			break;
1960 		}
1961 	}
1962 	DBGBH(("%s bh_handler exit\n", info->device_name));
1963 }
1964 
1965 static void bh_transmit(struct slgt_info *info)
1966 {
1967 	struct tty_struct *tty = info->port.tty;
1968 
1969 	DBGBH(("%s bh_transmit\n", info->device_name));
1970 	if (tty)
1971 		tty_wakeup(tty);
1972 }
1973 
1974 static void dsr_change(struct slgt_info *info, unsigned short status)
1975 {
1976 	if (status & BIT3) {
1977 		info->signals |= SerialSignal_DSR;
1978 		info->input_signal_events.dsr_up++;
1979 	} else {
1980 		info->signals &= ~SerialSignal_DSR;
1981 		info->input_signal_events.dsr_down++;
1982 	}
1983 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1984 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1985 		slgt_irq_off(info, IRQ_DSR);
1986 		return;
1987 	}
1988 	info->icount.dsr++;
1989 	wake_up_interruptible(&info->status_event_wait_q);
1990 	wake_up_interruptible(&info->event_wait_q);
1991 	info->pending_bh |= BH_STATUS;
1992 }
1993 
1994 static void cts_change(struct slgt_info *info, unsigned short status)
1995 {
1996 	if (status & BIT2) {
1997 		info->signals |= SerialSignal_CTS;
1998 		info->input_signal_events.cts_up++;
1999 	} else {
2000 		info->signals &= ~SerialSignal_CTS;
2001 		info->input_signal_events.cts_down++;
2002 	}
2003 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
2004 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2005 		slgt_irq_off(info, IRQ_CTS);
2006 		return;
2007 	}
2008 	info->icount.cts++;
2009 	wake_up_interruptible(&info->status_event_wait_q);
2010 	wake_up_interruptible(&info->event_wait_q);
2011 	info->pending_bh |= BH_STATUS;
2012 
2013 	if (tty_port_cts_enabled(&info->port)) {
2014 		if (info->port.tty) {
2015 			if (info->port.tty->hw_stopped) {
2016 				if (info->signals & SerialSignal_CTS) {
2017 		 			info->port.tty->hw_stopped = 0;
2018 					info->pending_bh |= BH_TRANSMIT;
2019 					return;
2020 				}
2021 			} else {
2022 				if (!(info->signals & SerialSignal_CTS))
2023 		 			info->port.tty->hw_stopped = 1;
2024 			}
2025 		}
2026 	}
2027 }
2028 
2029 static void dcd_change(struct slgt_info *info, unsigned short status)
2030 {
2031 	if (status & BIT1) {
2032 		info->signals |= SerialSignal_DCD;
2033 		info->input_signal_events.dcd_up++;
2034 	} else {
2035 		info->signals &= ~SerialSignal_DCD;
2036 		info->input_signal_events.dcd_down++;
2037 	}
2038 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
2039 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2040 		slgt_irq_off(info, IRQ_DCD);
2041 		return;
2042 	}
2043 	info->icount.dcd++;
2044 #if SYNCLINK_GENERIC_HDLC
2045 	if (info->netcount) {
2046 		if (info->signals & SerialSignal_DCD)
2047 			netif_carrier_on(info->netdev);
2048 		else
2049 			netif_carrier_off(info->netdev);
2050 	}
2051 #endif
2052 	wake_up_interruptible(&info->status_event_wait_q);
2053 	wake_up_interruptible(&info->event_wait_q);
2054 	info->pending_bh |= BH_STATUS;
2055 
2056 	if (tty_port_check_carrier(&info->port)) {
2057 		if (info->signals & SerialSignal_DCD)
2058 			wake_up_interruptible(&info->port.open_wait);
2059 		else {
2060 			if (info->port.tty)
2061 				tty_hangup(info->port.tty);
2062 		}
2063 	}
2064 }
2065 
2066 static void ri_change(struct slgt_info *info, unsigned short status)
2067 {
2068 	if (status & BIT0) {
2069 		info->signals |= SerialSignal_RI;
2070 		info->input_signal_events.ri_up++;
2071 	} else {
2072 		info->signals &= ~SerialSignal_RI;
2073 		info->input_signal_events.ri_down++;
2074 	}
2075 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2076 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2077 		slgt_irq_off(info, IRQ_RI);
2078 		return;
2079 	}
2080 	info->icount.rng++;
2081 	wake_up_interruptible(&info->status_event_wait_q);
2082 	wake_up_interruptible(&info->event_wait_q);
2083 	info->pending_bh |= BH_STATUS;
2084 }
2085 
2086 static void isr_rxdata(struct slgt_info *info)
2087 {
2088 	unsigned int count = info->rbuf_fill_count;
2089 	unsigned int i = info->rbuf_fill_index;
2090 	unsigned short reg;
2091 
2092 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2093 		reg = rd_reg16(info, RDR);
2094 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2095 		if (desc_complete(info->rbufs[i])) {
2096 			/* all buffers full */
2097 			rx_stop(info);
2098 			info->rx_restart = true;
2099 			continue;
2100 		}
2101 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2102 		/* async mode saves status byte to buffer for each data byte */
2103 		if (info->params.mode == MGSL_MODE_ASYNC)
2104 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2105 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2106 			/* buffer full or end of frame */
2107 			set_desc_count(info->rbufs[i], count);
2108 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2109 			info->rbuf_fill_count = count = 0;
2110 			if (++i == info->rbuf_count)
2111 				i = 0;
2112 			info->pending_bh |= BH_RECEIVE;
2113 		}
2114 	}
2115 
2116 	info->rbuf_fill_index = i;
2117 	info->rbuf_fill_count = count;
2118 }
2119 
2120 static void isr_serial(struct slgt_info *info)
2121 {
2122 	unsigned short status = rd_reg16(info, SSR);
2123 
2124 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2125 
2126 	wr_reg16(info, SSR, status); /* clear pending */
2127 
2128 	info->irq_occurred = true;
2129 
2130 	if (info->params.mode == MGSL_MODE_ASYNC) {
2131 		if (status & IRQ_TXIDLE) {
2132 			if (info->tx_active)
2133 				isr_txeom(info, status);
2134 		}
2135 		if (info->rx_pio && (status & IRQ_RXDATA))
2136 			isr_rxdata(info);
2137 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2138 			info->icount.brk++;
2139 			/* process break detection if tty control allows */
2140 			if (info->port.tty) {
2141 				if (!(status & info->ignore_status_mask)) {
2142 					if (info->read_status_mask & MASK_BREAK) {
2143 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2144 						if (info->port.flags & ASYNC_SAK)
2145 							do_SAK(info->port.tty);
2146 					}
2147 				}
2148 			}
2149 		}
2150 	} else {
2151 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2152 			isr_txeom(info, status);
2153 		if (info->rx_pio && (status & IRQ_RXDATA))
2154 			isr_rxdata(info);
2155 		if (status & IRQ_RXIDLE) {
2156 			if (status & RXIDLE)
2157 				info->icount.rxidle++;
2158 			else
2159 				info->icount.exithunt++;
2160 			wake_up_interruptible(&info->event_wait_q);
2161 		}
2162 
2163 		if (status & IRQ_RXOVER)
2164 			rx_start(info);
2165 	}
2166 
2167 	if (status & IRQ_DSR)
2168 		dsr_change(info, status);
2169 	if (status & IRQ_CTS)
2170 		cts_change(info, status);
2171 	if (status & IRQ_DCD)
2172 		dcd_change(info, status);
2173 	if (status & IRQ_RI)
2174 		ri_change(info, status);
2175 }
2176 
2177 static void isr_rdma(struct slgt_info *info)
2178 {
2179 	unsigned int status = rd_reg32(info, RDCSR);
2180 
2181 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2182 
2183 	/* RDCSR (rx DMA control/status)
2184 	 *
2185 	 * 31..07  reserved
2186 	 * 06      save status byte to DMA buffer
2187 	 * 05      error
2188 	 * 04      eol (end of list)
2189 	 * 03      eob (end of buffer)
2190 	 * 02      IRQ enable
2191 	 * 01      reset
2192 	 * 00      enable
2193 	 */
2194 	wr_reg32(info, RDCSR, status);	/* clear pending */
2195 
2196 	if (status & (BIT5 + BIT4)) {
2197 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2198 		info->rx_restart = true;
2199 	}
2200 	info->pending_bh |= BH_RECEIVE;
2201 }
2202 
2203 static void isr_tdma(struct slgt_info *info)
2204 {
2205 	unsigned int status = rd_reg32(info, TDCSR);
2206 
2207 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2208 
2209 	/* TDCSR (tx DMA control/status)
2210 	 *
2211 	 * 31..06  reserved
2212 	 * 05      error
2213 	 * 04      eol (end of list)
2214 	 * 03      eob (end of buffer)
2215 	 * 02      IRQ enable
2216 	 * 01      reset
2217 	 * 00      enable
2218 	 */
2219 	wr_reg32(info, TDCSR, status);	/* clear pending */
2220 
2221 	if (status & (BIT5 + BIT4 + BIT3)) {
2222 		// another transmit buffer has completed
2223 		// run bottom half to get more send data from user
2224 		info->pending_bh |= BH_TRANSMIT;
2225 	}
2226 }
2227 
2228 /*
2229  * return true if there are unsent tx DMA buffers, otherwise false
2230  *
2231  * if there are unsent buffers then info->tbuf_start
2232  * is set to index of first unsent buffer
2233  */
2234 static bool unsent_tbufs(struct slgt_info *info)
2235 {
2236 	unsigned int i = info->tbuf_current;
2237 	bool rc = false;
2238 
2239 	/*
2240 	 * search backwards from last loaded buffer (precedes tbuf_current)
2241 	 * for first unsent buffer (desc_count > 0)
2242 	 */
2243 
2244 	do {
2245 		if (i)
2246 			i--;
2247 		else
2248 			i = info->tbuf_count - 1;
2249 		if (!desc_count(info->tbufs[i]))
2250 			break;
2251 		info->tbuf_start = i;
2252 		rc = true;
2253 	} while (i != info->tbuf_current);
2254 
2255 	return rc;
2256 }
2257 
2258 static void isr_txeom(struct slgt_info *info, unsigned short status)
2259 {
2260 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2261 
2262 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2263 	tdma_reset(info);
2264 	if (status & IRQ_TXUNDER) {
2265 		unsigned short val = rd_reg16(info, TCR);
2266 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2267 		wr_reg16(info, TCR, val); /* clear reset bit */
2268 	}
2269 
2270 	if (info->tx_active) {
2271 		if (info->params.mode != MGSL_MODE_ASYNC) {
2272 			if (status & IRQ_TXUNDER)
2273 				info->icount.txunder++;
2274 			else if (status & IRQ_TXIDLE)
2275 				info->icount.txok++;
2276 		}
2277 
2278 		if (unsent_tbufs(info)) {
2279 			tx_start(info);
2280 			update_tx_timer(info);
2281 			return;
2282 		}
2283 		info->tx_active = false;
2284 
2285 		del_timer(&info->tx_timer);
2286 
2287 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2288 			info->signals &= ~SerialSignal_RTS;
2289 			info->drop_rts_on_tx_done = false;
2290 			set_signals(info);
2291 		}
2292 
2293 #if SYNCLINK_GENERIC_HDLC
2294 		if (info->netcount)
2295 			hdlcdev_tx_done(info);
2296 		else
2297 #endif
2298 		{
2299 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2300 				tx_stop(info);
2301 				return;
2302 			}
2303 			info->pending_bh |= BH_TRANSMIT;
2304 		}
2305 	}
2306 }
2307 
2308 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2309 {
2310 	struct cond_wait *w, *prev;
2311 
2312 	/* wake processes waiting for specific transitions */
2313 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2314 		if (w->data & changed) {
2315 			w->data = state;
2316 			wake_up_interruptible(&w->q);
2317 			if (prev != NULL)
2318 				prev->next = w->next;
2319 			else
2320 				info->gpio_wait_q = w->next;
2321 		} else
2322 			prev = w;
2323 	}
2324 }
2325 
2326 /* interrupt service routine
2327  *
2328  * 	irq	interrupt number
2329  * 	dev_id	device ID supplied during interrupt registration
2330  */
2331 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2332 {
2333 	struct slgt_info *info = dev_id;
2334 	unsigned int gsr;
2335 	unsigned int i;
2336 
2337 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2338 
2339 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2340 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2341 		info->irq_occurred = true;
2342 		for(i=0; i < info->port_count ; i++) {
2343 			if (info->port_array[i] == NULL)
2344 				continue;
2345 			spin_lock(&info->port_array[i]->lock);
2346 			if (gsr & (BIT8 << i))
2347 				isr_serial(info->port_array[i]);
2348 			if (gsr & (BIT16 << (i*2)))
2349 				isr_rdma(info->port_array[i]);
2350 			if (gsr & (BIT17 << (i*2)))
2351 				isr_tdma(info->port_array[i]);
2352 			spin_unlock(&info->port_array[i]->lock);
2353 		}
2354 	}
2355 
2356 	if (info->gpio_present) {
2357 		unsigned int state;
2358 		unsigned int changed;
2359 		spin_lock(&info->lock);
2360 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2361 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2362 			/* read latched state of GPIO signals */
2363 			state = rd_reg32(info, IOVR);
2364 			/* clear pending GPIO interrupt bits */
2365 			wr_reg32(info, IOSR, changed);
2366 			for (i=0 ; i < info->port_count ; i++) {
2367 				if (info->port_array[i] != NULL)
2368 					isr_gpio(info->port_array[i], changed, state);
2369 			}
2370 		}
2371 		spin_unlock(&info->lock);
2372 	}
2373 
2374 	for(i=0; i < info->port_count ; i++) {
2375 		struct slgt_info *port = info->port_array[i];
2376 		if (port == NULL)
2377 			continue;
2378 		spin_lock(&port->lock);
2379 		if ((port->port.count || port->netcount) &&
2380 		    port->pending_bh && !port->bh_running &&
2381 		    !port->bh_requested) {
2382 			DBGISR(("%s bh queued\n", port->device_name));
2383 			schedule_work(&port->task);
2384 			port->bh_requested = true;
2385 		}
2386 		spin_unlock(&port->lock);
2387 	}
2388 
2389 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2390 	return IRQ_HANDLED;
2391 }
2392 
2393 static int startup(struct slgt_info *info)
2394 {
2395 	DBGINFO(("%s startup\n", info->device_name));
2396 
2397 	if (tty_port_initialized(&info->port))
2398 		return 0;
2399 
2400 	if (!info->tx_buf) {
2401 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2402 		if (!info->tx_buf) {
2403 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2404 			return -ENOMEM;
2405 		}
2406 	}
2407 
2408 	info->pending_bh = 0;
2409 
2410 	memset(&info->icount, 0, sizeof(info->icount));
2411 
2412 	/* program hardware for current parameters */
2413 	change_params(info);
2414 
2415 	if (info->port.tty)
2416 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2417 
2418 	tty_port_set_initialized(&info->port, 1);
2419 
2420 	return 0;
2421 }
2422 
2423 /*
2424  *  called by close() and hangup() to shutdown hardware
2425  */
2426 static void shutdown(struct slgt_info *info)
2427 {
2428 	unsigned long flags;
2429 
2430 	if (!tty_port_initialized(&info->port))
2431 		return;
2432 
2433 	DBGINFO(("%s shutdown\n", info->device_name));
2434 
2435 	/* clear status wait queue because status changes */
2436 	/* can't happen after shutting down the hardware */
2437 	wake_up_interruptible(&info->status_event_wait_q);
2438 	wake_up_interruptible(&info->event_wait_q);
2439 
2440 	del_timer_sync(&info->tx_timer);
2441 	del_timer_sync(&info->rx_timer);
2442 
2443 	kfree(info->tx_buf);
2444 	info->tx_buf = NULL;
2445 
2446 	spin_lock_irqsave(&info->lock,flags);
2447 
2448 	tx_stop(info);
2449 	rx_stop(info);
2450 
2451 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2452 
2453  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2454 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2455 		set_signals(info);
2456 	}
2457 
2458 	flush_cond_wait(&info->gpio_wait_q);
2459 
2460 	spin_unlock_irqrestore(&info->lock,flags);
2461 
2462 	if (info->port.tty)
2463 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2464 
2465 	tty_port_set_initialized(&info->port, 0);
2466 }
2467 
2468 static void program_hw(struct slgt_info *info)
2469 {
2470 	unsigned long flags;
2471 
2472 	spin_lock_irqsave(&info->lock,flags);
2473 
2474 	rx_stop(info);
2475 	tx_stop(info);
2476 
2477 	if (info->params.mode != MGSL_MODE_ASYNC ||
2478 	    info->netcount)
2479 		sync_mode(info);
2480 	else
2481 		async_mode(info);
2482 
2483 	set_signals(info);
2484 
2485 	info->dcd_chkcount = 0;
2486 	info->cts_chkcount = 0;
2487 	info->ri_chkcount = 0;
2488 	info->dsr_chkcount = 0;
2489 
2490 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2491 	get_signals(info);
2492 
2493 	if (info->netcount ||
2494 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2495 		rx_start(info);
2496 
2497 	spin_unlock_irqrestore(&info->lock,flags);
2498 }
2499 
2500 /*
2501  * reconfigure adapter based on new parameters
2502  */
2503 static void change_params(struct slgt_info *info)
2504 {
2505 	unsigned cflag;
2506 	int bits_per_char;
2507 
2508 	if (!info->port.tty)
2509 		return;
2510 	DBGINFO(("%s change_params\n", info->device_name));
2511 
2512 	cflag = info->port.tty->termios.c_cflag;
2513 
2514 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2515 	/* otherwise assert RTS and DTR */
2516  	if (cflag & CBAUD)
2517 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2518 	else
2519 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2520 
2521 	/* byte size and parity */
2522 
2523 	switch (cflag & CSIZE) {
2524 	case CS5: info->params.data_bits = 5; break;
2525 	case CS6: info->params.data_bits = 6; break;
2526 	case CS7: info->params.data_bits = 7; break;
2527 	case CS8: info->params.data_bits = 8; break;
2528 	default:  info->params.data_bits = 7; break;
2529 	}
2530 
2531 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2532 
2533 	if (cflag & PARENB)
2534 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2535 	else
2536 		info->params.parity = ASYNC_PARITY_NONE;
2537 
2538 	/* calculate number of jiffies to transmit a full
2539 	 * FIFO (32 bytes) at specified data rate
2540 	 */
2541 	bits_per_char = info->params.data_bits +
2542 			info->params.stop_bits + 1;
2543 
2544 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2545 
2546 	if (info->params.data_rate) {
2547 		info->timeout = (32*HZ*bits_per_char) /
2548 				info->params.data_rate;
2549 	}
2550 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2551 
2552 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2553 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2554 
2555 	/* process tty input control flags */
2556 
2557 	info->read_status_mask = IRQ_RXOVER;
2558 	if (I_INPCK(info->port.tty))
2559 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2560 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2561 		info->read_status_mask |= MASK_BREAK;
2562 	if (I_IGNPAR(info->port.tty))
2563 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2564 	if (I_IGNBRK(info->port.tty)) {
2565 		info->ignore_status_mask |= MASK_BREAK;
2566 		/* If ignoring parity and break indicators, ignore
2567 		 * overruns too.  (For real raw support).
2568 		 */
2569 		if (I_IGNPAR(info->port.tty))
2570 			info->ignore_status_mask |= MASK_OVERRUN;
2571 	}
2572 
2573 	program_hw(info);
2574 }
2575 
2576 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2577 {
2578 	DBGINFO(("%s get_stats\n",  info->device_name));
2579 	if (!user_icount) {
2580 		memset(&info->icount, 0, sizeof(info->icount));
2581 	} else {
2582 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2583 			return -EFAULT;
2584 	}
2585 	return 0;
2586 }
2587 
2588 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2589 {
2590 	DBGINFO(("%s get_params\n", info->device_name));
2591 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2592 		return -EFAULT;
2593 	return 0;
2594 }
2595 
2596 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2597 {
2598  	unsigned long flags;
2599 	MGSL_PARAMS tmp_params;
2600 
2601 	DBGINFO(("%s set_params\n", info->device_name));
2602 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2603 		return -EFAULT;
2604 
2605 	spin_lock_irqsave(&info->lock, flags);
2606 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2607 		info->base_clock = tmp_params.clock_speed;
2608 	else
2609 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2610 	spin_unlock_irqrestore(&info->lock, flags);
2611 
2612 	program_hw(info);
2613 
2614 	return 0;
2615 }
2616 
2617 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2618 {
2619 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2620 	if (put_user(info->idle_mode, idle_mode))
2621 		return -EFAULT;
2622 	return 0;
2623 }
2624 
2625 static int set_txidle(struct slgt_info *info, int idle_mode)
2626 {
2627  	unsigned long flags;
2628 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2629 	spin_lock_irqsave(&info->lock,flags);
2630 	info->idle_mode = idle_mode;
2631 	if (info->params.mode != MGSL_MODE_ASYNC)
2632 		tx_set_idle(info);
2633 	spin_unlock_irqrestore(&info->lock,flags);
2634 	return 0;
2635 }
2636 
2637 static int tx_enable(struct slgt_info *info, int enable)
2638 {
2639  	unsigned long flags;
2640 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2641 	spin_lock_irqsave(&info->lock,flags);
2642 	if (enable) {
2643 		if (!info->tx_enabled)
2644 			tx_start(info);
2645 	} else {
2646 		if (info->tx_enabled)
2647 			tx_stop(info);
2648 	}
2649 	spin_unlock_irqrestore(&info->lock,flags);
2650 	return 0;
2651 }
2652 
2653 /*
2654  * abort transmit HDLC frame
2655  */
2656 static int tx_abort(struct slgt_info *info)
2657 {
2658  	unsigned long flags;
2659 	DBGINFO(("%s tx_abort\n", info->device_name));
2660 	spin_lock_irqsave(&info->lock,flags);
2661 	tdma_reset(info);
2662 	spin_unlock_irqrestore(&info->lock,flags);
2663 	return 0;
2664 }
2665 
2666 static int rx_enable(struct slgt_info *info, int enable)
2667 {
2668  	unsigned long flags;
2669 	unsigned int rbuf_fill_level;
2670 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2671 	spin_lock_irqsave(&info->lock,flags);
2672 	/*
2673 	 * enable[31..16] = receive DMA buffer fill level
2674 	 * 0 = noop (leave fill level unchanged)
2675 	 * fill level must be multiple of 4 and <= buffer size
2676 	 */
2677 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2678 	if (rbuf_fill_level) {
2679 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2680 			spin_unlock_irqrestore(&info->lock, flags);
2681 			return -EINVAL;
2682 		}
2683 		info->rbuf_fill_level = rbuf_fill_level;
2684 		if (rbuf_fill_level < 128)
2685 			info->rx_pio = 1; /* PIO mode */
2686 		else
2687 			info->rx_pio = 0; /* DMA mode */
2688 		rx_stop(info); /* restart receiver to use new fill level */
2689 	}
2690 
2691 	/*
2692 	 * enable[1..0] = receiver enable command
2693 	 * 0 = disable
2694 	 * 1 = enable
2695 	 * 2 = enable or force hunt mode if already enabled
2696 	 */
2697 	enable &= 3;
2698 	if (enable) {
2699 		if (!info->rx_enabled)
2700 			rx_start(info);
2701 		else if (enable == 2) {
2702 			/* force hunt mode (write 1 to RCR[3]) */
2703 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2704 		}
2705 	} else {
2706 		if (info->rx_enabled)
2707 			rx_stop(info);
2708 	}
2709 	spin_unlock_irqrestore(&info->lock,flags);
2710 	return 0;
2711 }
2712 
2713 /*
2714  *  wait for specified event to occur
2715  */
2716 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2717 {
2718  	unsigned long flags;
2719 	int s;
2720 	int rc=0;
2721 	struct mgsl_icount cprev, cnow;
2722 	int events;
2723 	int mask;
2724 	struct	_input_signal_events oldsigs, newsigs;
2725 	DECLARE_WAITQUEUE(wait, current);
2726 
2727 	if (get_user(mask, mask_ptr))
2728 		return -EFAULT;
2729 
2730 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2731 
2732 	spin_lock_irqsave(&info->lock,flags);
2733 
2734 	/* return immediately if state matches requested events */
2735 	get_signals(info);
2736 	s = info->signals;
2737 
2738 	events = mask &
2739 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2740  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2741 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2742 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2743 	if (events) {
2744 		spin_unlock_irqrestore(&info->lock,flags);
2745 		goto exit;
2746 	}
2747 
2748 	/* save current irq counts */
2749 	cprev = info->icount;
2750 	oldsigs = info->input_signal_events;
2751 
2752 	/* enable hunt and idle irqs if needed */
2753 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2754 		unsigned short val = rd_reg16(info, SCR);
2755 		if (!(val & IRQ_RXIDLE))
2756 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2757 	}
2758 
2759 	set_current_state(TASK_INTERRUPTIBLE);
2760 	add_wait_queue(&info->event_wait_q, &wait);
2761 
2762 	spin_unlock_irqrestore(&info->lock,flags);
2763 
2764 	for(;;) {
2765 		schedule();
2766 		if (signal_pending(current)) {
2767 			rc = -ERESTARTSYS;
2768 			break;
2769 		}
2770 
2771 		/* get current irq counts */
2772 		spin_lock_irqsave(&info->lock,flags);
2773 		cnow = info->icount;
2774 		newsigs = info->input_signal_events;
2775 		set_current_state(TASK_INTERRUPTIBLE);
2776 		spin_unlock_irqrestore(&info->lock,flags);
2777 
2778 		/* if no change, wait aborted for some reason */
2779 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2780 		    newsigs.dsr_down == oldsigs.dsr_down &&
2781 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2782 		    newsigs.dcd_down == oldsigs.dcd_down &&
2783 		    newsigs.cts_up   == oldsigs.cts_up   &&
2784 		    newsigs.cts_down == oldsigs.cts_down &&
2785 		    newsigs.ri_up    == oldsigs.ri_up    &&
2786 		    newsigs.ri_down  == oldsigs.ri_down  &&
2787 		    cnow.exithunt    == cprev.exithunt   &&
2788 		    cnow.rxidle      == cprev.rxidle) {
2789 			rc = -EIO;
2790 			break;
2791 		}
2792 
2793 		events = mask &
2794 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2795 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2796 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2797 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2798 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2799 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2800 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2801 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2802 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2803 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2804 		if (events)
2805 			break;
2806 
2807 		cprev = cnow;
2808 		oldsigs = newsigs;
2809 	}
2810 
2811 	remove_wait_queue(&info->event_wait_q, &wait);
2812 	set_current_state(TASK_RUNNING);
2813 
2814 
2815 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2816 		spin_lock_irqsave(&info->lock,flags);
2817 		if (!waitqueue_active(&info->event_wait_q)) {
2818 			/* disable enable exit hunt mode/idle rcvd IRQs */
2819 			wr_reg16(info, SCR,
2820 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2821 		}
2822 		spin_unlock_irqrestore(&info->lock,flags);
2823 	}
2824 exit:
2825 	if (rc == 0)
2826 		rc = put_user(events, mask_ptr);
2827 	return rc;
2828 }
2829 
2830 static int get_interface(struct slgt_info *info, int __user *if_mode)
2831 {
2832 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2833 	if (put_user(info->if_mode, if_mode))
2834 		return -EFAULT;
2835 	return 0;
2836 }
2837 
2838 static int set_interface(struct slgt_info *info, int if_mode)
2839 {
2840  	unsigned long flags;
2841 	unsigned short val;
2842 
2843 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2844 	spin_lock_irqsave(&info->lock,flags);
2845 	info->if_mode = if_mode;
2846 
2847 	msc_set_vcr(info);
2848 
2849 	/* TCR (tx control) 07  1=RTS driver control */
2850 	val = rd_reg16(info, TCR);
2851 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2852 		val |= BIT7;
2853 	else
2854 		val &= ~BIT7;
2855 	wr_reg16(info, TCR, val);
2856 
2857 	spin_unlock_irqrestore(&info->lock,flags);
2858 	return 0;
2859 }
2860 
2861 static int get_xsync(struct slgt_info *info, int __user *xsync)
2862 {
2863 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2864 	if (put_user(info->xsync, xsync))
2865 		return -EFAULT;
2866 	return 0;
2867 }
2868 
2869 /*
2870  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2871  *
2872  * sync pattern is contained in least significant bytes of value
2873  * most significant byte of sync pattern is oldest (1st sent/detected)
2874  */
2875 static int set_xsync(struct slgt_info *info, int xsync)
2876 {
2877 	unsigned long flags;
2878 
2879 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2880 	spin_lock_irqsave(&info->lock, flags);
2881 	info->xsync = xsync;
2882 	wr_reg32(info, XSR, xsync);
2883 	spin_unlock_irqrestore(&info->lock, flags);
2884 	return 0;
2885 }
2886 
2887 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2888 {
2889 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2890 	if (put_user(info->xctrl, xctrl))
2891 		return -EFAULT;
2892 	return 0;
2893 }
2894 
2895 /*
2896  * set extended control options
2897  *
2898  * xctrl[31:19] reserved, must be zero
2899  * xctrl[18:17] extended sync pattern length in bytes
2900  *              00 = 1 byte  in xsr[7:0]
2901  *              01 = 2 bytes in xsr[15:0]
2902  *              10 = 3 bytes in xsr[23:0]
2903  *              11 = 4 bytes in xsr[31:0]
2904  * xctrl[16]    1 = enable terminal count, 0=disabled
2905  * xctrl[15:0]  receive terminal count for fixed length packets
2906  *              value is count minus one (0 = 1 byte packet)
2907  *              when terminal count is reached, receiver
2908  *              automatically returns to hunt mode and receive
2909  *              FIFO contents are flushed to DMA buffers with
2910  *              end of frame (EOF) status
2911  */
2912 static int set_xctrl(struct slgt_info *info, int xctrl)
2913 {
2914 	unsigned long flags;
2915 
2916 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2917 	spin_lock_irqsave(&info->lock, flags);
2918 	info->xctrl = xctrl;
2919 	wr_reg32(info, XCR, xctrl);
2920 	spin_unlock_irqrestore(&info->lock, flags);
2921 	return 0;
2922 }
2923 
2924 /*
2925  * set general purpose IO pin state and direction
2926  *
2927  * user_gpio fields:
2928  * state   each bit indicates a pin state
2929  * smask   set bit indicates pin state to set
2930  * dir     each bit indicates a pin direction (0=input, 1=output)
2931  * dmask   set bit indicates pin direction to set
2932  */
2933 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2934 {
2935  	unsigned long flags;
2936 	struct gpio_desc gpio;
2937 	__u32 data;
2938 
2939 	if (!info->gpio_present)
2940 		return -EINVAL;
2941 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2942 		return -EFAULT;
2943 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2944 		 info->device_name, gpio.state, gpio.smask,
2945 		 gpio.dir, gpio.dmask));
2946 
2947 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2948 	if (gpio.dmask) {
2949 		data = rd_reg32(info, IODR);
2950 		data |= gpio.dmask & gpio.dir;
2951 		data &= ~(gpio.dmask & ~gpio.dir);
2952 		wr_reg32(info, IODR, data);
2953 	}
2954 	if (gpio.smask) {
2955 		data = rd_reg32(info, IOVR);
2956 		data |= gpio.smask & gpio.state;
2957 		data &= ~(gpio.smask & ~gpio.state);
2958 		wr_reg32(info, IOVR, data);
2959 	}
2960 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2961 
2962 	return 0;
2963 }
2964 
2965 /*
2966  * get general purpose IO pin state and direction
2967  */
2968 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2969 {
2970 	struct gpio_desc gpio;
2971 	if (!info->gpio_present)
2972 		return -EINVAL;
2973 	gpio.state = rd_reg32(info, IOVR);
2974 	gpio.smask = 0xffffffff;
2975 	gpio.dir   = rd_reg32(info, IODR);
2976 	gpio.dmask = 0xffffffff;
2977 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2978 		return -EFAULT;
2979 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2980 		 info->device_name, gpio.state, gpio.dir));
2981 	return 0;
2982 }
2983 
2984 /*
2985  * conditional wait facility
2986  */
2987 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2988 {
2989 	init_waitqueue_head(&w->q);
2990 	init_waitqueue_entry(&w->wait, current);
2991 	w->data = data;
2992 }
2993 
2994 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2995 {
2996 	set_current_state(TASK_INTERRUPTIBLE);
2997 	add_wait_queue(&w->q, &w->wait);
2998 	w->next = *head;
2999 	*head = w;
3000 }
3001 
3002 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3003 {
3004 	struct cond_wait *w, *prev;
3005 	remove_wait_queue(&cw->q, &cw->wait);
3006 	set_current_state(TASK_RUNNING);
3007 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3008 		if (w == cw) {
3009 			if (prev != NULL)
3010 				prev->next = w->next;
3011 			else
3012 				*head = w->next;
3013 			break;
3014 		}
3015 	}
3016 }
3017 
3018 static void flush_cond_wait(struct cond_wait **head)
3019 {
3020 	while (*head != NULL) {
3021 		wake_up_interruptible(&(*head)->q);
3022 		*head = (*head)->next;
3023 	}
3024 }
3025 
3026 /*
3027  * wait for general purpose I/O pin(s) to enter specified state
3028  *
3029  * user_gpio fields:
3030  * state - bit indicates target pin state
3031  * smask - set bit indicates watched pin
3032  *
3033  * The wait ends when at least one watched pin enters the specified
3034  * state. When 0 (no error) is returned, user_gpio->state is set to the
3035  * state of all GPIO pins when the wait ends.
3036  *
3037  * Note: Each pin may be a dedicated input, dedicated output, or
3038  * configurable input/output. The number and configuration of pins
3039  * varies with the specific adapter model. Only input pins (dedicated
3040  * or configured) can be monitored with this function.
3041  */
3042 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3043 {
3044  	unsigned long flags;
3045 	int rc = 0;
3046 	struct gpio_desc gpio;
3047 	struct cond_wait wait;
3048 	u32 state;
3049 
3050 	if (!info->gpio_present)
3051 		return -EINVAL;
3052 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3053 		return -EFAULT;
3054 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3055 		 info->device_name, gpio.state, gpio.smask));
3056 	/* ignore output pins identified by set IODR bit */
3057 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3058 		return -EINVAL;
3059 	init_cond_wait(&wait, gpio.smask);
3060 
3061 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3062 	/* enable interrupts for watched pins */
3063 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3064 	/* get current pin states */
3065 	state = rd_reg32(info, IOVR);
3066 
3067 	if (gpio.smask & ~(state ^ gpio.state)) {
3068 		/* already in target state */
3069 		gpio.state = state;
3070 	} else {
3071 		/* wait for target state */
3072 		add_cond_wait(&info->gpio_wait_q, &wait);
3073 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3074 		schedule();
3075 		if (signal_pending(current))
3076 			rc = -ERESTARTSYS;
3077 		else
3078 			gpio.state = wait.data;
3079 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3080 		remove_cond_wait(&info->gpio_wait_q, &wait);
3081 	}
3082 
3083 	/* disable all GPIO interrupts if no waiting processes */
3084 	if (info->gpio_wait_q == NULL)
3085 		wr_reg32(info, IOER, 0);
3086 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3087 
3088 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3089 		rc = -EFAULT;
3090 	return rc;
3091 }
3092 
3093 static int modem_input_wait(struct slgt_info *info,int arg)
3094 {
3095  	unsigned long flags;
3096 	int rc;
3097 	struct mgsl_icount cprev, cnow;
3098 	DECLARE_WAITQUEUE(wait, current);
3099 
3100 	/* save current irq counts */
3101 	spin_lock_irqsave(&info->lock,flags);
3102 	cprev = info->icount;
3103 	add_wait_queue(&info->status_event_wait_q, &wait);
3104 	set_current_state(TASK_INTERRUPTIBLE);
3105 	spin_unlock_irqrestore(&info->lock,flags);
3106 
3107 	for(;;) {
3108 		schedule();
3109 		if (signal_pending(current)) {
3110 			rc = -ERESTARTSYS;
3111 			break;
3112 		}
3113 
3114 		/* get new irq counts */
3115 		spin_lock_irqsave(&info->lock,flags);
3116 		cnow = info->icount;
3117 		set_current_state(TASK_INTERRUPTIBLE);
3118 		spin_unlock_irqrestore(&info->lock,flags);
3119 
3120 		/* if no change, wait aborted for some reason */
3121 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3122 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3123 			rc = -EIO;
3124 			break;
3125 		}
3126 
3127 		/* check for change in caller specified modem input */
3128 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3129 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3130 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3131 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3132 			rc = 0;
3133 			break;
3134 		}
3135 
3136 		cprev = cnow;
3137 	}
3138 	remove_wait_queue(&info->status_event_wait_q, &wait);
3139 	set_current_state(TASK_RUNNING);
3140 	return rc;
3141 }
3142 
3143 /*
3144  *  return state of serial control and status signals
3145  */
3146 static int tiocmget(struct tty_struct *tty)
3147 {
3148 	struct slgt_info *info = tty->driver_data;
3149 	unsigned int result;
3150  	unsigned long flags;
3151 
3152 	spin_lock_irqsave(&info->lock,flags);
3153  	get_signals(info);
3154 	spin_unlock_irqrestore(&info->lock,flags);
3155 
3156 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3157 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3158 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3159 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3160 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3161 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3162 
3163 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3164 	return result;
3165 }
3166 
3167 /*
3168  * set modem control signals (DTR/RTS)
3169  *
3170  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3171  *		TIOCMSET = set/clear signal values
3172  * 	value	bit mask for command
3173  */
3174 static int tiocmset(struct tty_struct *tty,
3175 		    unsigned int set, unsigned int clear)
3176 {
3177 	struct slgt_info *info = tty->driver_data;
3178  	unsigned long flags;
3179 
3180 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3181 
3182 	if (set & TIOCM_RTS)
3183 		info->signals |= SerialSignal_RTS;
3184 	if (set & TIOCM_DTR)
3185 		info->signals |= SerialSignal_DTR;
3186 	if (clear & TIOCM_RTS)
3187 		info->signals &= ~SerialSignal_RTS;
3188 	if (clear & TIOCM_DTR)
3189 		info->signals &= ~SerialSignal_DTR;
3190 
3191 	spin_lock_irqsave(&info->lock,flags);
3192 	set_signals(info);
3193 	spin_unlock_irqrestore(&info->lock,flags);
3194 	return 0;
3195 }
3196 
3197 static int carrier_raised(struct tty_port *port)
3198 {
3199 	unsigned long flags;
3200 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3201 
3202 	spin_lock_irqsave(&info->lock,flags);
3203 	get_signals(info);
3204 	spin_unlock_irqrestore(&info->lock,flags);
3205 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3206 }
3207 
3208 static void dtr_rts(struct tty_port *port, int on)
3209 {
3210 	unsigned long flags;
3211 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3212 
3213 	spin_lock_irqsave(&info->lock,flags);
3214 	if (on)
3215 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3216 	else
3217 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3218 	set_signals(info);
3219 	spin_unlock_irqrestore(&info->lock,flags);
3220 }
3221 
3222 
3223 /*
3224  *  block current process until the device is ready to open
3225  */
3226 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3227 			   struct slgt_info *info)
3228 {
3229 	DECLARE_WAITQUEUE(wait, current);
3230 	int		retval;
3231 	bool		do_clocal = false;
3232 	unsigned long	flags;
3233 	int		cd;
3234 	struct tty_port *port = &info->port;
3235 
3236 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3237 
3238 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3239 		/* nonblock mode is set or port is not enabled */
3240 		tty_port_set_active(port, 1);
3241 		return 0;
3242 	}
3243 
3244 	if (C_CLOCAL(tty))
3245 		do_clocal = true;
3246 
3247 	/* Wait for carrier detect and the line to become
3248 	 * free (i.e., not in use by the callout).  While we are in
3249 	 * this loop, port->count is dropped by one, so that
3250 	 * close() knows when to free things.  We restore it upon
3251 	 * exit, either normal or abnormal.
3252 	 */
3253 
3254 	retval = 0;
3255 	add_wait_queue(&port->open_wait, &wait);
3256 
3257 	spin_lock_irqsave(&info->lock, flags);
3258 	port->count--;
3259 	spin_unlock_irqrestore(&info->lock, flags);
3260 	port->blocked_open++;
3261 
3262 	while (1) {
3263 		if (C_BAUD(tty) && tty_port_initialized(port))
3264 			tty_port_raise_dtr_rts(port);
3265 
3266 		set_current_state(TASK_INTERRUPTIBLE);
3267 
3268 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3269 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3270 					-EAGAIN : -ERESTARTSYS;
3271 			break;
3272 		}
3273 
3274 		cd = tty_port_carrier_raised(port);
3275 		if (do_clocal || cd)
3276 			break;
3277 
3278 		if (signal_pending(current)) {
3279 			retval = -ERESTARTSYS;
3280 			break;
3281 		}
3282 
3283 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3284 		tty_unlock(tty);
3285 		schedule();
3286 		tty_lock(tty);
3287 	}
3288 
3289 	set_current_state(TASK_RUNNING);
3290 	remove_wait_queue(&port->open_wait, &wait);
3291 
3292 	if (!tty_hung_up_p(filp))
3293 		port->count++;
3294 	port->blocked_open--;
3295 
3296 	if (!retval)
3297 		tty_port_set_active(port, 1);
3298 
3299 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3300 	return retval;
3301 }
3302 
3303 /*
3304  * allocate buffers used for calling line discipline receive_buf
3305  * directly in synchronous mode
3306  * note: add 5 bytes to max frame size to allow appending
3307  * 32-bit CRC and status byte when configured to do so
3308  */
3309 static int alloc_tmp_rbuf(struct slgt_info *info)
3310 {
3311 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3312 	if (info->tmp_rbuf == NULL)
3313 		return -ENOMEM;
3314 	/* unused flag buffer to satisfy receive_buf calling interface */
3315 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3316 	if (!info->flag_buf) {
3317 		kfree(info->tmp_rbuf);
3318 		info->tmp_rbuf = NULL;
3319 		return -ENOMEM;
3320 	}
3321 	return 0;
3322 }
3323 
3324 static void free_tmp_rbuf(struct slgt_info *info)
3325 {
3326 	kfree(info->tmp_rbuf);
3327 	info->tmp_rbuf = NULL;
3328 	kfree(info->flag_buf);
3329 	info->flag_buf = NULL;
3330 }
3331 
3332 /*
3333  * allocate DMA descriptor lists.
3334  */
3335 static int alloc_desc(struct slgt_info *info)
3336 {
3337 	unsigned int i;
3338 	unsigned int pbufs;
3339 
3340 	/* allocate memory to hold descriptor lists */
3341 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3342 					&info->bufs_dma_addr, GFP_KERNEL);
3343 	if (info->bufs == NULL)
3344 		return -ENOMEM;
3345 
3346 	info->rbufs = (struct slgt_desc*)info->bufs;
3347 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3348 
3349 	pbufs = (unsigned int)info->bufs_dma_addr;
3350 
3351 	/*
3352 	 * Build circular lists of descriptors
3353 	 */
3354 
3355 	for (i=0; i < info->rbuf_count; i++) {
3356 		/* physical address of this descriptor */
3357 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3358 
3359 		/* physical address of next descriptor */
3360 		if (i == info->rbuf_count - 1)
3361 			info->rbufs[i].next = cpu_to_le32(pbufs);
3362 		else
3363 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3364 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3365 	}
3366 
3367 	for (i=0; i < info->tbuf_count; i++) {
3368 		/* physical address of this descriptor */
3369 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3370 
3371 		/* physical address of next descriptor */
3372 		if (i == info->tbuf_count - 1)
3373 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3374 		else
3375 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3376 	}
3377 
3378 	return 0;
3379 }
3380 
3381 static void free_desc(struct slgt_info *info)
3382 {
3383 	if (info->bufs != NULL) {
3384 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3385 				  info->bufs, info->bufs_dma_addr);
3386 		info->bufs  = NULL;
3387 		info->rbufs = NULL;
3388 		info->tbufs = NULL;
3389 	}
3390 }
3391 
3392 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3393 {
3394 	int i;
3395 	for (i=0; i < count; i++) {
3396 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3397 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3398 		if (!bufs[i].buf)
3399 			return -ENOMEM;
3400 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3401 	}
3402 	return 0;
3403 }
3404 
3405 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3406 {
3407 	int i;
3408 	for (i=0; i < count; i++) {
3409 		if (bufs[i].buf == NULL)
3410 			continue;
3411 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3412 				  bufs[i].buf_dma_addr);
3413 		bufs[i].buf = NULL;
3414 	}
3415 }
3416 
3417 static int alloc_dma_bufs(struct slgt_info *info)
3418 {
3419 	info->rbuf_count = 32;
3420 	info->tbuf_count = 32;
3421 
3422 	if (alloc_desc(info) < 0 ||
3423 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3424 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3425 	    alloc_tmp_rbuf(info) < 0) {
3426 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3427 		return -ENOMEM;
3428 	}
3429 	reset_rbufs(info);
3430 	return 0;
3431 }
3432 
3433 static void free_dma_bufs(struct slgt_info *info)
3434 {
3435 	if (info->bufs) {
3436 		free_bufs(info, info->rbufs, info->rbuf_count);
3437 		free_bufs(info, info->tbufs, info->tbuf_count);
3438 		free_desc(info);
3439 	}
3440 	free_tmp_rbuf(info);
3441 }
3442 
3443 static int claim_resources(struct slgt_info *info)
3444 {
3445 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3446 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3447 			info->device_name, info->phys_reg_addr));
3448 		info->init_error = DiagStatus_AddressConflict;
3449 		goto errout;
3450 	}
3451 	else
3452 		info->reg_addr_requested = true;
3453 
3454 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3455 	if (!info->reg_addr) {
3456 		DBGERR(("%s can't map device registers, addr=%08X\n",
3457 			info->device_name, info->phys_reg_addr));
3458 		info->init_error = DiagStatus_CantAssignPciResources;
3459 		goto errout;
3460 	}
3461 	return 0;
3462 
3463 errout:
3464 	release_resources(info);
3465 	return -ENODEV;
3466 }
3467 
3468 static void release_resources(struct slgt_info *info)
3469 {
3470 	if (info->irq_requested) {
3471 		free_irq(info->irq_level, info);
3472 		info->irq_requested = false;
3473 	}
3474 
3475 	if (info->reg_addr_requested) {
3476 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3477 		info->reg_addr_requested = false;
3478 	}
3479 
3480 	if (info->reg_addr) {
3481 		iounmap(info->reg_addr);
3482 		info->reg_addr = NULL;
3483 	}
3484 }
3485 
3486 /* Add the specified device instance data structure to the
3487  * global linked list of devices and increment the device count.
3488  */
3489 static void add_device(struct slgt_info *info)
3490 {
3491 	char *devstr;
3492 
3493 	info->next_device = NULL;
3494 	info->line = slgt_device_count;
3495 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3496 
3497 	if (info->line < MAX_DEVICES) {
3498 		if (maxframe[info->line])
3499 			info->max_frame_size = maxframe[info->line];
3500 	}
3501 
3502 	slgt_device_count++;
3503 
3504 	if (!slgt_device_list)
3505 		slgt_device_list = info;
3506 	else {
3507 		struct slgt_info *current_dev = slgt_device_list;
3508 		while(current_dev->next_device)
3509 			current_dev = current_dev->next_device;
3510 		current_dev->next_device = info;
3511 	}
3512 
3513 	if (info->max_frame_size < 4096)
3514 		info->max_frame_size = 4096;
3515 	else if (info->max_frame_size > 65535)
3516 		info->max_frame_size = 65535;
3517 
3518 	switch(info->pdev->device) {
3519 	case SYNCLINK_GT_DEVICE_ID:
3520 		devstr = "GT";
3521 		break;
3522 	case SYNCLINK_GT2_DEVICE_ID:
3523 		devstr = "GT2";
3524 		break;
3525 	case SYNCLINK_GT4_DEVICE_ID:
3526 		devstr = "GT4";
3527 		break;
3528 	case SYNCLINK_AC_DEVICE_ID:
3529 		devstr = "AC";
3530 		info->params.mode = MGSL_MODE_ASYNC;
3531 		break;
3532 	default:
3533 		devstr = "(unknown model)";
3534 	}
3535 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3536 		devstr, info->device_name, info->phys_reg_addr,
3537 		info->irq_level, info->max_frame_size);
3538 
3539 #if SYNCLINK_GENERIC_HDLC
3540 	hdlcdev_init(info);
3541 #endif
3542 }
3543 
3544 static const struct tty_port_operations slgt_port_ops = {
3545 	.carrier_raised = carrier_raised,
3546 	.dtr_rts = dtr_rts,
3547 };
3548 
3549 /*
3550  *  allocate device instance structure, return NULL on failure
3551  */
3552 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3553 {
3554 	struct slgt_info *info;
3555 
3556 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3557 
3558 	if (!info) {
3559 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3560 			driver_name, adapter_num, port_num));
3561 	} else {
3562 		tty_port_init(&info->port);
3563 		info->port.ops = &slgt_port_ops;
3564 		info->magic = MGSL_MAGIC;
3565 		INIT_WORK(&info->task, bh_handler);
3566 		info->max_frame_size = 4096;
3567 		info->base_clock = 14745600;
3568 		info->rbuf_fill_level = DMABUFSIZE;
3569 		info->port.close_delay = 5*HZ/10;
3570 		info->port.closing_wait = 30*HZ;
3571 		init_waitqueue_head(&info->status_event_wait_q);
3572 		init_waitqueue_head(&info->event_wait_q);
3573 		spin_lock_init(&info->netlock);
3574 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3575 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3576 		info->adapter_num = adapter_num;
3577 		info->port_num = port_num;
3578 
3579 		timer_setup(&info->tx_timer, tx_timeout, 0);
3580 		timer_setup(&info->rx_timer, rx_timeout, 0);
3581 
3582 		/* Copy configuration info to device instance data */
3583 		info->pdev = pdev;
3584 		info->irq_level = pdev->irq;
3585 		info->phys_reg_addr = pci_resource_start(pdev,0);
3586 
3587 		info->bus_type = MGSL_BUS_TYPE_PCI;
3588 		info->irq_flags = IRQF_SHARED;
3589 
3590 		info->init_error = -1; /* assume error, set to 0 on successful init */
3591 	}
3592 
3593 	return info;
3594 }
3595 
3596 static void device_init(int adapter_num, struct pci_dev *pdev)
3597 {
3598 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3599 	int i;
3600 	int port_count = 1;
3601 
3602 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3603 		port_count = 2;
3604 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3605 		port_count = 4;
3606 
3607 	/* allocate device instances for all ports */
3608 	for (i=0; i < port_count; ++i) {
3609 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3610 		if (port_array[i] == NULL) {
3611 			for (--i; i >= 0; --i) {
3612 				tty_port_destroy(&port_array[i]->port);
3613 				kfree(port_array[i]);
3614 			}
3615 			return;
3616 		}
3617 	}
3618 
3619 	/* give copy of port_array to all ports and add to device list  */
3620 	for (i=0; i < port_count; ++i) {
3621 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3622 		add_device(port_array[i]);
3623 		port_array[i]->port_count = port_count;
3624 		spin_lock_init(&port_array[i]->lock);
3625 	}
3626 
3627 	/* Allocate and claim adapter resources */
3628 	if (!claim_resources(port_array[0])) {
3629 
3630 		alloc_dma_bufs(port_array[0]);
3631 
3632 		/* copy resource information from first port to others */
3633 		for (i = 1; i < port_count; ++i) {
3634 			port_array[i]->irq_level = port_array[0]->irq_level;
3635 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3636 			alloc_dma_bufs(port_array[i]);
3637 		}
3638 
3639 		if (request_irq(port_array[0]->irq_level,
3640 					slgt_interrupt,
3641 					port_array[0]->irq_flags,
3642 					port_array[0]->device_name,
3643 					port_array[0]) < 0) {
3644 			DBGERR(("%s request_irq failed IRQ=%d\n",
3645 				port_array[0]->device_name,
3646 				port_array[0]->irq_level));
3647 		} else {
3648 			port_array[0]->irq_requested = true;
3649 			adapter_test(port_array[0]);
3650 			for (i=1 ; i < port_count ; i++) {
3651 				port_array[i]->init_error = port_array[0]->init_error;
3652 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3653 			}
3654 		}
3655 	}
3656 
3657 	for (i = 0; i < port_count; ++i) {
3658 		struct slgt_info *info = port_array[i];
3659 		tty_port_register_device(&info->port, serial_driver, info->line,
3660 				&info->pdev->dev);
3661 	}
3662 }
3663 
3664 static int init_one(struct pci_dev *dev,
3665 			      const struct pci_device_id *ent)
3666 {
3667 	if (pci_enable_device(dev)) {
3668 		printk("error enabling pci device %p\n", dev);
3669 		return -EIO;
3670 	}
3671 	pci_set_master(dev);
3672 	device_init(slgt_device_count, dev);
3673 	return 0;
3674 }
3675 
3676 static void remove_one(struct pci_dev *dev)
3677 {
3678 }
3679 
3680 static const struct tty_operations ops = {
3681 	.open = open,
3682 	.close = close,
3683 	.write = write,
3684 	.put_char = put_char,
3685 	.flush_chars = flush_chars,
3686 	.write_room = write_room,
3687 	.chars_in_buffer = chars_in_buffer,
3688 	.flush_buffer = flush_buffer,
3689 	.ioctl = ioctl,
3690 	.compat_ioctl = slgt_compat_ioctl,
3691 	.throttle = throttle,
3692 	.unthrottle = unthrottle,
3693 	.send_xchar = send_xchar,
3694 	.break_ctl = set_break,
3695 	.wait_until_sent = wait_until_sent,
3696 	.set_termios = set_termios,
3697 	.stop = tx_hold,
3698 	.start = tx_release,
3699 	.hangup = hangup,
3700 	.tiocmget = tiocmget,
3701 	.tiocmset = tiocmset,
3702 	.get_icount = get_icount,
3703 	.proc_show = synclink_gt_proc_show,
3704 };
3705 
3706 static void slgt_cleanup(void)
3707 {
3708 	int rc;
3709 	struct slgt_info *info;
3710 	struct slgt_info *tmp;
3711 
3712 	printk(KERN_INFO "unload %s\n", driver_name);
3713 
3714 	if (serial_driver) {
3715 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3716 			tty_unregister_device(serial_driver, info->line);
3717 		rc = tty_unregister_driver(serial_driver);
3718 		if (rc)
3719 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3720 		put_tty_driver(serial_driver);
3721 	}
3722 
3723 	/* reset devices */
3724 	info = slgt_device_list;
3725 	while(info) {
3726 		reset_port(info);
3727 		info = info->next_device;
3728 	}
3729 
3730 	/* release devices */
3731 	info = slgt_device_list;
3732 	while(info) {
3733 #if SYNCLINK_GENERIC_HDLC
3734 		hdlcdev_exit(info);
3735 #endif
3736 		free_dma_bufs(info);
3737 		free_tmp_rbuf(info);
3738 		if (info->port_num == 0)
3739 			release_resources(info);
3740 		tmp = info;
3741 		info = info->next_device;
3742 		tty_port_destroy(&tmp->port);
3743 		kfree(tmp);
3744 	}
3745 
3746 	if (pci_registered)
3747 		pci_unregister_driver(&pci_driver);
3748 }
3749 
3750 /*
3751  *  Driver initialization entry point.
3752  */
3753 static int __init slgt_init(void)
3754 {
3755 	int rc;
3756 
3757 	printk(KERN_INFO "%s\n", driver_name);
3758 
3759 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3760 	if (!serial_driver) {
3761 		printk("%s can't allocate tty driver\n", driver_name);
3762 		return -ENOMEM;
3763 	}
3764 
3765 	/* Initialize the tty_driver structure */
3766 
3767 	serial_driver->driver_name = slgt_driver_name;
3768 	serial_driver->name = tty_dev_prefix;
3769 	serial_driver->major = ttymajor;
3770 	serial_driver->minor_start = 64;
3771 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3772 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3773 	serial_driver->init_termios = tty_std_termios;
3774 	serial_driver->init_termios.c_cflag =
3775 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3776 	serial_driver->init_termios.c_ispeed = 9600;
3777 	serial_driver->init_termios.c_ospeed = 9600;
3778 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3779 	tty_set_operations(serial_driver, &ops);
3780 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3781 		DBGERR(("%s can't register serial driver\n", driver_name));
3782 		put_tty_driver(serial_driver);
3783 		serial_driver = NULL;
3784 		goto error;
3785 	}
3786 
3787 	printk(KERN_INFO "%s, tty major#%d\n",
3788 	       driver_name, serial_driver->major);
3789 
3790 	slgt_device_count = 0;
3791 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3792 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3793 		goto error;
3794 	}
3795 	pci_registered = true;
3796 
3797 	if (!slgt_device_list)
3798 		printk("%s no devices found\n",driver_name);
3799 
3800 	return 0;
3801 
3802 error:
3803 	slgt_cleanup();
3804 	return rc;
3805 }
3806 
3807 static void __exit slgt_exit(void)
3808 {
3809 	slgt_cleanup();
3810 }
3811 
3812 module_init(slgt_init);
3813 module_exit(slgt_exit);
3814 
3815 /*
3816  * register access routines
3817  */
3818 
3819 #define CALC_REGADDR() \
3820 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3821 	if (addr >= 0x80) \
3822 		reg_addr += (info->port_num) * 32; \
3823 	else if (addr >= 0x40)	\
3824 		reg_addr += (info->port_num) * 16;
3825 
3826 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3827 {
3828 	CALC_REGADDR();
3829 	return readb((void __iomem *)reg_addr);
3830 }
3831 
3832 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3833 {
3834 	CALC_REGADDR();
3835 	writeb(value, (void __iomem *)reg_addr);
3836 }
3837 
3838 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3839 {
3840 	CALC_REGADDR();
3841 	return readw((void __iomem *)reg_addr);
3842 }
3843 
3844 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3845 {
3846 	CALC_REGADDR();
3847 	writew(value, (void __iomem *)reg_addr);
3848 }
3849 
3850 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3851 {
3852 	CALC_REGADDR();
3853 	return readl((void __iomem *)reg_addr);
3854 }
3855 
3856 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3857 {
3858 	CALC_REGADDR();
3859 	writel(value, (void __iomem *)reg_addr);
3860 }
3861 
3862 static void rdma_reset(struct slgt_info *info)
3863 {
3864 	unsigned int i;
3865 
3866 	/* set reset bit */
3867 	wr_reg32(info, RDCSR, BIT1);
3868 
3869 	/* wait for enable bit cleared */
3870 	for(i=0 ; i < 1000 ; i++)
3871 		if (!(rd_reg32(info, RDCSR) & BIT0))
3872 			break;
3873 }
3874 
3875 static void tdma_reset(struct slgt_info *info)
3876 {
3877 	unsigned int i;
3878 
3879 	/* set reset bit */
3880 	wr_reg32(info, TDCSR, BIT1);
3881 
3882 	/* wait for enable bit cleared */
3883 	for(i=0 ; i < 1000 ; i++)
3884 		if (!(rd_reg32(info, TDCSR) & BIT0))
3885 			break;
3886 }
3887 
3888 /*
3889  * enable internal loopback
3890  * TxCLK and RxCLK are generated from BRG
3891  * and TxD is looped back to RxD internally.
3892  */
3893 static void enable_loopback(struct slgt_info *info)
3894 {
3895 	/* SCR (serial control) BIT2=loopback enable */
3896 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3897 
3898 	if (info->params.mode != MGSL_MODE_ASYNC) {
3899 		/* CCR (clock control)
3900 		 * 07..05  tx clock source (010 = BRG)
3901 		 * 04..02  rx clock source (010 = BRG)
3902 		 * 01      auxclk enable   (0 = disable)
3903 		 * 00      BRG enable      (1 = enable)
3904 		 *
3905 		 * 0100 1001
3906 		 */
3907 		wr_reg8(info, CCR, 0x49);
3908 
3909 		/* set speed if available, otherwise use default */
3910 		if (info->params.clock_speed)
3911 			set_rate(info, info->params.clock_speed);
3912 		else
3913 			set_rate(info, 3686400);
3914 	}
3915 }
3916 
3917 /*
3918  *  set baud rate generator to specified rate
3919  */
3920 static void set_rate(struct slgt_info *info, u32 rate)
3921 {
3922 	unsigned int div;
3923 	unsigned int osc = info->base_clock;
3924 
3925 	/* div = osc/rate - 1
3926 	 *
3927 	 * Round div up if osc/rate is not integer to
3928 	 * force to next slowest rate.
3929 	 */
3930 
3931 	if (rate) {
3932 		div = osc/rate;
3933 		if (!(osc % rate) && div)
3934 			div--;
3935 		wr_reg16(info, BDR, (unsigned short)div);
3936 	}
3937 }
3938 
3939 static void rx_stop(struct slgt_info *info)
3940 {
3941 	unsigned short val;
3942 
3943 	/* disable and reset receiver */
3944 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3945 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3946 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3947 
3948 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3949 
3950 	/* clear pending rx interrupts */
3951 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3952 
3953 	rdma_reset(info);
3954 
3955 	info->rx_enabled = false;
3956 	info->rx_restart = false;
3957 }
3958 
3959 static void rx_start(struct slgt_info *info)
3960 {
3961 	unsigned short val;
3962 
3963 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3964 
3965 	/* clear pending rx overrun IRQ */
3966 	wr_reg16(info, SSR, IRQ_RXOVER);
3967 
3968 	/* reset and disable receiver */
3969 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3970 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3971 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3972 
3973 	rdma_reset(info);
3974 	reset_rbufs(info);
3975 
3976 	if (info->rx_pio) {
3977 		/* rx request when rx FIFO not empty */
3978 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3979 		slgt_irq_on(info, IRQ_RXDATA);
3980 		if (info->params.mode == MGSL_MODE_ASYNC) {
3981 			/* enable saving of rx status */
3982 			wr_reg32(info, RDCSR, BIT6);
3983 		}
3984 	} else {
3985 		/* rx request when rx FIFO half full */
3986 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3987 		/* set 1st descriptor address */
3988 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3989 
3990 		if (info->params.mode != MGSL_MODE_ASYNC) {
3991 			/* enable rx DMA and DMA interrupt */
3992 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3993 		} else {
3994 			/* enable saving of rx status, rx DMA and DMA interrupt */
3995 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3996 		}
3997 	}
3998 
3999 	slgt_irq_on(info, IRQ_RXOVER);
4000 
4001 	/* enable receiver */
4002 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4003 
4004 	info->rx_restart = false;
4005 	info->rx_enabled = true;
4006 }
4007 
4008 static void tx_start(struct slgt_info *info)
4009 {
4010 	if (!info->tx_enabled) {
4011 		wr_reg16(info, TCR,
4012 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4013 		info->tx_enabled = true;
4014 	}
4015 
4016 	if (desc_count(info->tbufs[info->tbuf_start])) {
4017 		info->drop_rts_on_tx_done = false;
4018 
4019 		if (info->params.mode != MGSL_MODE_ASYNC) {
4020 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4021 				get_signals(info);
4022 				if (!(info->signals & SerialSignal_RTS)) {
4023 					info->signals |= SerialSignal_RTS;
4024 					set_signals(info);
4025 					info->drop_rts_on_tx_done = true;
4026 				}
4027 			}
4028 
4029 			slgt_irq_off(info, IRQ_TXDATA);
4030 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4031 			/* clear tx idle and underrun status bits */
4032 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4033 		} else {
4034 			slgt_irq_off(info, IRQ_TXDATA);
4035 			slgt_irq_on(info, IRQ_TXIDLE);
4036 			/* clear tx idle status bit */
4037 			wr_reg16(info, SSR, IRQ_TXIDLE);
4038 		}
4039 		/* set 1st descriptor address and start DMA */
4040 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4041 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4042 		info->tx_active = true;
4043 	}
4044 }
4045 
4046 static void tx_stop(struct slgt_info *info)
4047 {
4048 	unsigned short val;
4049 
4050 	del_timer(&info->tx_timer);
4051 
4052 	tdma_reset(info);
4053 
4054 	/* reset and disable transmitter */
4055 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4056 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4057 
4058 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4059 
4060 	/* clear tx idle and underrun status bit */
4061 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4062 
4063 	reset_tbufs(info);
4064 
4065 	info->tx_enabled = false;
4066 	info->tx_active = false;
4067 }
4068 
4069 static void reset_port(struct slgt_info *info)
4070 {
4071 	if (!info->reg_addr)
4072 		return;
4073 
4074 	tx_stop(info);
4075 	rx_stop(info);
4076 
4077 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4078 	set_signals(info);
4079 
4080 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4081 }
4082 
4083 static void reset_adapter(struct slgt_info *info)
4084 {
4085 	int i;
4086 	for (i=0; i < info->port_count; ++i) {
4087 		if (info->port_array[i])
4088 			reset_port(info->port_array[i]);
4089 	}
4090 }
4091 
4092 static void async_mode(struct slgt_info *info)
4093 {
4094   	unsigned short val;
4095 
4096 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4097 	tx_stop(info);
4098 	rx_stop(info);
4099 
4100 	/* TCR (tx control)
4101 	 *
4102 	 * 15..13  mode, 010=async
4103 	 * 12..10  encoding, 000=NRZ
4104 	 * 09      parity enable
4105 	 * 08      1=odd parity, 0=even parity
4106 	 * 07      1=RTS driver control
4107 	 * 06      1=break enable
4108 	 * 05..04  character length
4109 	 *         00=5 bits
4110 	 *         01=6 bits
4111 	 *         10=7 bits
4112 	 *         11=8 bits
4113 	 * 03      0=1 stop bit, 1=2 stop bits
4114 	 * 02      reset
4115 	 * 01      enable
4116 	 * 00      auto-CTS enable
4117 	 */
4118 	val = 0x4000;
4119 
4120 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4121 		val |= BIT7;
4122 
4123 	if (info->params.parity != ASYNC_PARITY_NONE) {
4124 		val |= BIT9;
4125 		if (info->params.parity == ASYNC_PARITY_ODD)
4126 			val |= BIT8;
4127 	}
4128 
4129 	switch (info->params.data_bits)
4130 	{
4131 	case 6: val |= BIT4; break;
4132 	case 7: val |= BIT5; break;
4133 	case 8: val |= BIT5 + BIT4; break;
4134 	}
4135 
4136 	if (info->params.stop_bits != 1)
4137 		val |= BIT3;
4138 
4139 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4140 		val |= BIT0;
4141 
4142 	wr_reg16(info, TCR, val);
4143 
4144 	/* RCR (rx control)
4145 	 *
4146 	 * 15..13  mode, 010=async
4147 	 * 12..10  encoding, 000=NRZ
4148 	 * 09      parity enable
4149 	 * 08      1=odd parity, 0=even parity
4150 	 * 07..06  reserved, must be 0
4151 	 * 05..04  character length
4152 	 *         00=5 bits
4153 	 *         01=6 bits
4154 	 *         10=7 bits
4155 	 *         11=8 bits
4156 	 * 03      reserved, must be zero
4157 	 * 02      reset
4158 	 * 01      enable
4159 	 * 00      auto-DCD enable
4160 	 */
4161 	val = 0x4000;
4162 
4163 	if (info->params.parity != ASYNC_PARITY_NONE) {
4164 		val |= BIT9;
4165 		if (info->params.parity == ASYNC_PARITY_ODD)
4166 			val |= BIT8;
4167 	}
4168 
4169 	switch (info->params.data_bits)
4170 	{
4171 	case 6: val |= BIT4; break;
4172 	case 7: val |= BIT5; break;
4173 	case 8: val |= BIT5 + BIT4; break;
4174 	}
4175 
4176 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4177 		val |= BIT0;
4178 
4179 	wr_reg16(info, RCR, val);
4180 
4181 	/* CCR (clock control)
4182 	 *
4183 	 * 07..05  011 = tx clock source is BRG/16
4184 	 * 04..02  010 = rx clock source is BRG
4185 	 * 01      0 = auxclk disabled
4186 	 * 00      1 = BRG enabled
4187 	 *
4188 	 * 0110 1001
4189 	 */
4190 	wr_reg8(info, CCR, 0x69);
4191 
4192 	msc_set_vcr(info);
4193 
4194 	/* SCR (serial control)
4195 	 *
4196 	 * 15  1=tx req on FIFO half empty
4197 	 * 14  1=rx req on FIFO half full
4198 	 * 13  tx data  IRQ enable
4199 	 * 12  tx idle  IRQ enable
4200 	 * 11  rx break on IRQ enable
4201 	 * 10  rx data  IRQ enable
4202 	 * 09  rx break off IRQ enable
4203 	 * 08  overrun  IRQ enable
4204 	 * 07  DSR      IRQ enable
4205 	 * 06  CTS      IRQ enable
4206 	 * 05  DCD      IRQ enable
4207 	 * 04  RI       IRQ enable
4208 	 * 03  0=16x sampling, 1=8x sampling
4209 	 * 02  1=txd->rxd internal loopback enable
4210 	 * 01  reserved, must be zero
4211 	 * 00  1=master IRQ enable
4212 	 */
4213 	val = BIT15 + BIT14 + BIT0;
4214 	/* JCR[8] : 1 = x8 async mode feature available */
4215 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4216 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4217 	     (info->base_clock % (info->params.data_rate * 16)))) {
4218 		/* use 8x sampling */
4219 		val |= BIT3;
4220 		set_rate(info, info->params.data_rate * 8);
4221 	} else {
4222 		/* use 16x sampling */
4223 		set_rate(info, info->params.data_rate * 16);
4224 	}
4225 	wr_reg16(info, SCR, val);
4226 
4227 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4228 
4229 	if (info->params.loopback)
4230 		enable_loopback(info);
4231 }
4232 
4233 static void sync_mode(struct slgt_info *info)
4234 {
4235 	unsigned short val;
4236 
4237 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4238 	tx_stop(info);
4239 	rx_stop(info);
4240 
4241 	/* TCR (tx control)
4242 	 *
4243 	 * 15..13  mode
4244 	 *         000=HDLC/SDLC
4245 	 *         001=raw bit synchronous
4246 	 *         010=asynchronous/isochronous
4247 	 *         011=monosync byte synchronous
4248 	 *         100=bisync byte synchronous
4249 	 *         101=xsync byte synchronous
4250 	 * 12..10  encoding
4251 	 * 09      CRC enable
4252 	 * 08      CRC32
4253 	 * 07      1=RTS driver control
4254 	 * 06      preamble enable
4255 	 * 05..04  preamble length
4256 	 * 03      share open/close flag
4257 	 * 02      reset
4258 	 * 01      enable
4259 	 * 00      auto-CTS enable
4260 	 */
4261 	val = BIT2;
4262 
4263 	switch(info->params.mode) {
4264 	case MGSL_MODE_XSYNC:
4265 		val |= BIT15 + BIT13;
4266 		break;
4267 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4268 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4269 	case MGSL_MODE_RAW:      val |= BIT13; break;
4270 	}
4271 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4272 		val |= BIT7;
4273 
4274 	switch(info->params.encoding)
4275 	{
4276 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4277 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4278 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4279 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4280 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4281 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4282 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4283 	}
4284 
4285 	switch (info->params.crc_type & HDLC_CRC_MASK)
4286 	{
4287 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4288 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4289 	}
4290 
4291 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4292 		val |= BIT6;
4293 
4294 	switch (info->params.preamble_length)
4295 	{
4296 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4297 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4298 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4299 	}
4300 
4301 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4302 		val |= BIT0;
4303 
4304 	wr_reg16(info, TCR, val);
4305 
4306 	/* TPR (transmit preamble) */
4307 
4308 	switch (info->params.preamble)
4309 	{
4310 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4311 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4312 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4313 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4314 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4315 	default:                          val = 0x7e; break;
4316 	}
4317 	wr_reg8(info, TPR, (unsigned char)val);
4318 
4319 	/* RCR (rx control)
4320 	 *
4321 	 * 15..13  mode
4322 	 *         000=HDLC/SDLC
4323 	 *         001=raw bit synchronous
4324 	 *         010=asynchronous/isochronous
4325 	 *         011=monosync byte synchronous
4326 	 *         100=bisync byte synchronous
4327 	 *         101=xsync byte synchronous
4328 	 * 12..10  encoding
4329 	 * 09      CRC enable
4330 	 * 08      CRC32
4331 	 * 07..03  reserved, must be 0
4332 	 * 02      reset
4333 	 * 01      enable
4334 	 * 00      auto-DCD enable
4335 	 */
4336 	val = 0;
4337 
4338 	switch(info->params.mode) {
4339 	case MGSL_MODE_XSYNC:
4340 		val |= BIT15 + BIT13;
4341 		break;
4342 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4343 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4344 	case MGSL_MODE_RAW:      val |= BIT13; break;
4345 	}
4346 
4347 	switch(info->params.encoding)
4348 	{
4349 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4350 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4351 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4352 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4353 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4354 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4355 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4356 	}
4357 
4358 	switch (info->params.crc_type & HDLC_CRC_MASK)
4359 	{
4360 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4361 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4362 	}
4363 
4364 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4365 		val |= BIT0;
4366 
4367 	wr_reg16(info, RCR, val);
4368 
4369 	/* CCR (clock control)
4370 	 *
4371 	 * 07..05  tx clock source
4372 	 * 04..02  rx clock source
4373 	 * 01      auxclk enable
4374 	 * 00      BRG enable
4375 	 */
4376 	val = 0;
4377 
4378 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4379 	{
4380 		// when RxC source is DPLL, BRG generates 16X DPLL
4381 		// reference clock, so take TxC from BRG/16 to get
4382 		// transmit clock at actual data rate
4383 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4384 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4385 		else
4386 			val |= BIT6;	/* 010, txclk = BRG */
4387 	}
4388 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4389 		val |= BIT7;	/* 100, txclk = DPLL Input */
4390 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4391 		val |= BIT5;	/* 001, txclk = RXC Input */
4392 
4393 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4394 		val |= BIT3;	/* 010, rxclk = BRG */
4395 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4396 		val |= BIT4;	/* 100, rxclk = DPLL */
4397 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4398 		val |= BIT2;	/* 001, rxclk = TXC Input */
4399 
4400 	if (info->params.clock_speed)
4401 		val |= BIT1 + BIT0;
4402 
4403 	wr_reg8(info, CCR, (unsigned char)val);
4404 
4405 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4406 	{
4407 		// program DPLL mode
4408 		switch(info->params.encoding)
4409 		{
4410 		case HDLC_ENCODING_BIPHASE_MARK:
4411 		case HDLC_ENCODING_BIPHASE_SPACE:
4412 			val = BIT7; break;
4413 		case HDLC_ENCODING_BIPHASE_LEVEL:
4414 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4415 			val = BIT7 + BIT6; break;
4416 		default: val = BIT6;	// NRZ encodings
4417 		}
4418 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4419 
4420 		// DPLL requires a 16X reference clock from BRG
4421 		set_rate(info, info->params.clock_speed * 16);
4422 	}
4423 	else
4424 		set_rate(info, info->params.clock_speed);
4425 
4426 	tx_set_idle(info);
4427 
4428 	msc_set_vcr(info);
4429 
4430 	/* SCR (serial control)
4431 	 *
4432 	 * 15  1=tx req on FIFO half empty
4433 	 * 14  1=rx req on FIFO half full
4434 	 * 13  tx data  IRQ enable
4435 	 * 12  tx idle  IRQ enable
4436 	 * 11  underrun IRQ enable
4437 	 * 10  rx data  IRQ enable
4438 	 * 09  rx idle  IRQ enable
4439 	 * 08  overrun  IRQ enable
4440 	 * 07  DSR      IRQ enable
4441 	 * 06  CTS      IRQ enable
4442 	 * 05  DCD      IRQ enable
4443 	 * 04  RI       IRQ enable
4444 	 * 03  reserved, must be zero
4445 	 * 02  1=txd->rxd internal loopback enable
4446 	 * 01  reserved, must be zero
4447 	 * 00  1=master IRQ enable
4448 	 */
4449 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4450 
4451 	if (info->params.loopback)
4452 		enable_loopback(info);
4453 }
4454 
4455 /*
4456  *  set transmit idle mode
4457  */
4458 static void tx_set_idle(struct slgt_info *info)
4459 {
4460 	unsigned char val;
4461 	unsigned short tcr;
4462 
4463 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4464 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4465 	 */
4466 	tcr = rd_reg16(info, TCR);
4467 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4468 		/* disable preamble, set idle size to 16 bits */
4469 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4470 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4471 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4472 	} else if (!(tcr & BIT6)) {
4473 		/* preamble is disabled, set idle size to 8 bits */
4474 		tcr &= ~(BIT5 + BIT4);
4475 	}
4476 	wr_reg16(info, TCR, tcr);
4477 
4478 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4479 		/* LSB of custom tx idle specified in tx idle register */
4480 		val = (unsigned char)(info->idle_mode & 0xff);
4481 	} else {
4482 		/* standard 8 bit idle patterns */
4483 		switch(info->idle_mode)
4484 		{
4485 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4486 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4487 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4488 		case HDLC_TXIDLE_ZEROS:
4489 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4490 		default:                         val = 0xff;
4491 		}
4492 	}
4493 
4494 	wr_reg8(info, TIR, val);
4495 }
4496 
4497 /*
4498  * get state of V24 status (input) signals
4499  */
4500 static void get_signals(struct slgt_info *info)
4501 {
4502 	unsigned short status = rd_reg16(info, SSR);
4503 
4504 	/* clear all serial signals except RTS and DTR */
4505 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4506 
4507 	if (status & BIT3)
4508 		info->signals |= SerialSignal_DSR;
4509 	if (status & BIT2)
4510 		info->signals |= SerialSignal_CTS;
4511 	if (status & BIT1)
4512 		info->signals |= SerialSignal_DCD;
4513 	if (status & BIT0)
4514 		info->signals |= SerialSignal_RI;
4515 }
4516 
4517 /*
4518  * set V.24 Control Register based on current configuration
4519  */
4520 static void msc_set_vcr(struct slgt_info *info)
4521 {
4522 	unsigned char val = 0;
4523 
4524 	/* VCR (V.24 control)
4525 	 *
4526 	 * 07..04  serial IF select
4527 	 * 03      DTR
4528 	 * 02      RTS
4529 	 * 01      LL
4530 	 * 00      RL
4531 	 */
4532 
4533 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4534 	{
4535 	case MGSL_INTERFACE_RS232:
4536 		val |= BIT5; /* 0010 */
4537 		break;
4538 	case MGSL_INTERFACE_V35:
4539 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4540 		break;
4541 	case MGSL_INTERFACE_RS422:
4542 		val |= BIT6; /* 0100 */
4543 		break;
4544 	}
4545 
4546 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4547 		val |= BIT4;
4548 	if (info->signals & SerialSignal_DTR)
4549 		val |= BIT3;
4550 	if (info->signals & SerialSignal_RTS)
4551 		val |= BIT2;
4552 	if (info->if_mode & MGSL_INTERFACE_LL)
4553 		val |= BIT1;
4554 	if (info->if_mode & MGSL_INTERFACE_RL)
4555 		val |= BIT0;
4556 	wr_reg8(info, VCR, val);
4557 }
4558 
4559 /*
4560  * set state of V24 control (output) signals
4561  */
4562 static void set_signals(struct slgt_info *info)
4563 {
4564 	unsigned char val = rd_reg8(info, VCR);
4565 	if (info->signals & SerialSignal_DTR)
4566 		val |= BIT3;
4567 	else
4568 		val &= ~BIT3;
4569 	if (info->signals & SerialSignal_RTS)
4570 		val |= BIT2;
4571 	else
4572 		val &= ~BIT2;
4573 	wr_reg8(info, VCR, val);
4574 }
4575 
4576 /*
4577  * free range of receive DMA buffers (i to last)
4578  */
4579 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4580 {
4581 	int done = 0;
4582 
4583 	while(!done) {
4584 		/* reset current buffer for reuse */
4585 		info->rbufs[i].status = 0;
4586 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4587 		if (i == last)
4588 			done = 1;
4589 		if (++i == info->rbuf_count)
4590 			i = 0;
4591 	}
4592 	info->rbuf_current = i;
4593 }
4594 
4595 /*
4596  * mark all receive DMA buffers as free
4597  */
4598 static void reset_rbufs(struct slgt_info *info)
4599 {
4600 	free_rbufs(info, 0, info->rbuf_count - 1);
4601 	info->rbuf_fill_index = 0;
4602 	info->rbuf_fill_count = 0;
4603 }
4604 
4605 /*
4606  * pass receive HDLC frame to upper layer
4607  *
4608  * return true if frame available, otherwise false
4609  */
4610 static bool rx_get_frame(struct slgt_info *info)
4611 {
4612 	unsigned int start, end;
4613 	unsigned short status;
4614 	unsigned int framesize = 0;
4615 	unsigned long flags;
4616 	struct tty_struct *tty = info->port.tty;
4617 	unsigned char addr_field = 0xff;
4618 	unsigned int crc_size = 0;
4619 
4620 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4621 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4622 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4623 	}
4624 
4625 check_again:
4626 
4627 	framesize = 0;
4628 	addr_field = 0xff;
4629 	start = end = info->rbuf_current;
4630 
4631 	for (;;) {
4632 		if (!desc_complete(info->rbufs[end]))
4633 			goto cleanup;
4634 
4635 		if (framesize == 0 && info->params.addr_filter != 0xff)
4636 			addr_field = info->rbufs[end].buf[0];
4637 
4638 		framesize += desc_count(info->rbufs[end]);
4639 
4640 		if (desc_eof(info->rbufs[end]))
4641 			break;
4642 
4643 		if (++end == info->rbuf_count)
4644 			end = 0;
4645 
4646 		if (end == info->rbuf_current) {
4647 			if (info->rx_enabled){
4648 				spin_lock_irqsave(&info->lock,flags);
4649 				rx_start(info);
4650 				spin_unlock_irqrestore(&info->lock,flags);
4651 			}
4652 			goto cleanup;
4653 		}
4654 	}
4655 
4656 	/* status
4657 	 *
4658 	 * 15      buffer complete
4659 	 * 14..06  reserved
4660 	 * 05..04  residue
4661 	 * 02      eof (end of frame)
4662 	 * 01      CRC error
4663 	 * 00      abort
4664 	 */
4665 	status = desc_status(info->rbufs[end]);
4666 
4667 	/* ignore CRC bit if not using CRC (bit is undefined) */
4668 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4669 		status &= ~BIT1;
4670 
4671 	if (framesize == 0 ||
4672 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4673 		free_rbufs(info, start, end);
4674 		goto check_again;
4675 	}
4676 
4677 	if (framesize < (2 + crc_size) || status & BIT0) {
4678 		info->icount.rxshort++;
4679 		framesize = 0;
4680 	} else if (status & BIT1) {
4681 		info->icount.rxcrc++;
4682 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4683 			framesize = 0;
4684 	}
4685 
4686 #if SYNCLINK_GENERIC_HDLC
4687 	if (framesize == 0) {
4688 		info->netdev->stats.rx_errors++;
4689 		info->netdev->stats.rx_frame_errors++;
4690 	}
4691 #endif
4692 
4693 	DBGBH(("%s rx frame status=%04X size=%d\n",
4694 		info->device_name, status, framesize));
4695 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4696 
4697 	if (framesize) {
4698 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4699 			framesize -= crc_size;
4700 			crc_size = 0;
4701 		}
4702 
4703 		if (framesize > info->max_frame_size + crc_size)
4704 			info->icount.rxlong++;
4705 		else {
4706 			/* copy dma buffer(s) to contiguous temp buffer */
4707 			int copy_count = framesize;
4708 			int i = start;
4709 			unsigned char *p = info->tmp_rbuf;
4710 			info->tmp_rbuf_count = framesize;
4711 
4712 			info->icount.rxok++;
4713 
4714 			while(copy_count) {
4715 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4716 				memcpy(p, info->rbufs[i].buf, partial_count);
4717 				p += partial_count;
4718 				copy_count -= partial_count;
4719 				if (++i == info->rbuf_count)
4720 					i = 0;
4721 			}
4722 
4723 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4724 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4725 				framesize++;
4726 			}
4727 
4728 #if SYNCLINK_GENERIC_HDLC
4729 			if (info->netcount)
4730 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4731 			else
4732 #endif
4733 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4734 		}
4735 	}
4736 	free_rbufs(info, start, end);
4737 	return true;
4738 
4739 cleanup:
4740 	return false;
4741 }
4742 
4743 /*
4744  * pass receive buffer (RAW synchronous mode) to tty layer
4745  * return true if buffer available, otherwise false
4746  */
4747 static bool rx_get_buf(struct slgt_info *info)
4748 {
4749 	unsigned int i = info->rbuf_current;
4750 	unsigned int count;
4751 
4752 	if (!desc_complete(info->rbufs[i]))
4753 		return false;
4754 	count = desc_count(info->rbufs[i]);
4755 	switch(info->params.mode) {
4756 	case MGSL_MODE_MONOSYNC:
4757 	case MGSL_MODE_BISYNC:
4758 	case MGSL_MODE_XSYNC:
4759 		/* ignore residue in byte synchronous modes */
4760 		if (desc_residue(info->rbufs[i]))
4761 			count--;
4762 		break;
4763 	}
4764 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4765 	DBGINFO(("rx_get_buf size=%d\n", count));
4766 	if (count)
4767 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4768 				  info->flag_buf, count);
4769 	free_rbufs(info, i, i);
4770 	return true;
4771 }
4772 
4773 static void reset_tbufs(struct slgt_info *info)
4774 {
4775 	unsigned int i;
4776 	info->tbuf_current = 0;
4777 	for (i=0 ; i < info->tbuf_count ; i++) {
4778 		info->tbufs[i].status = 0;
4779 		info->tbufs[i].count  = 0;
4780 	}
4781 }
4782 
4783 /*
4784  * return number of free transmit DMA buffers
4785  */
4786 static unsigned int free_tbuf_count(struct slgt_info *info)
4787 {
4788 	unsigned int count = 0;
4789 	unsigned int i = info->tbuf_current;
4790 
4791 	do
4792 	{
4793 		if (desc_count(info->tbufs[i]))
4794 			break; /* buffer in use */
4795 		++count;
4796 		if (++i == info->tbuf_count)
4797 			i=0;
4798 	} while (i != info->tbuf_current);
4799 
4800 	/* if tx DMA active, last zero count buffer is in use */
4801 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4802 		--count;
4803 
4804 	return count;
4805 }
4806 
4807 /*
4808  * return number of bytes in unsent transmit DMA buffers
4809  * and the serial controller tx FIFO
4810  */
4811 static unsigned int tbuf_bytes(struct slgt_info *info)
4812 {
4813 	unsigned int total_count = 0;
4814 	unsigned int i = info->tbuf_current;
4815 	unsigned int reg_value;
4816 	unsigned int count;
4817 	unsigned int active_buf_count = 0;
4818 
4819 	/*
4820 	 * Add descriptor counts for all tx DMA buffers.
4821 	 * If count is zero (cleared by DMA controller after read),
4822 	 * the buffer is complete or is actively being read from.
4823 	 *
4824 	 * Record buf_count of last buffer with zero count starting
4825 	 * from current ring position. buf_count is mirror
4826 	 * copy of count and is not cleared by serial controller.
4827 	 * If DMA controller is active, that buffer is actively
4828 	 * being read so add to total.
4829 	 */
4830 	do {
4831 		count = desc_count(info->tbufs[i]);
4832 		if (count)
4833 			total_count += count;
4834 		else if (!total_count)
4835 			active_buf_count = info->tbufs[i].buf_count;
4836 		if (++i == info->tbuf_count)
4837 			i = 0;
4838 	} while (i != info->tbuf_current);
4839 
4840 	/* read tx DMA status register */
4841 	reg_value = rd_reg32(info, TDCSR);
4842 
4843 	/* if tx DMA active, last zero count buffer is in use */
4844 	if (reg_value & BIT0)
4845 		total_count += active_buf_count;
4846 
4847 	/* add tx FIFO count = reg_value[15..8] */
4848 	total_count += (reg_value >> 8) & 0xff;
4849 
4850 	/* if transmitter active add one byte for shift register */
4851 	if (info->tx_active)
4852 		total_count++;
4853 
4854 	return total_count;
4855 }
4856 
4857 /*
4858  * load data into transmit DMA buffer ring and start transmitter if needed
4859  * return true if data accepted, otherwise false (buffers full)
4860  */
4861 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4862 {
4863 	unsigned short count;
4864 	unsigned int i;
4865 	struct slgt_desc *d;
4866 
4867 	/* check required buffer space */
4868 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4869 		return false;
4870 
4871 	DBGDATA(info, buf, size, "tx");
4872 
4873 	/*
4874 	 * copy data to one or more DMA buffers in circular ring
4875 	 * tbuf_start   = first buffer for this data
4876 	 * tbuf_current = next free buffer
4877 	 *
4878 	 * Copy all data before making data visible to DMA controller by
4879 	 * setting descriptor count of the first buffer.
4880 	 * This prevents an active DMA controller from reading the first DMA
4881 	 * buffers of a frame and stopping before the final buffers are filled.
4882 	 */
4883 
4884 	info->tbuf_start = i = info->tbuf_current;
4885 
4886 	while (size) {
4887 		d = &info->tbufs[i];
4888 
4889 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4890 		memcpy(d->buf, buf, count);
4891 
4892 		size -= count;
4893 		buf  += count;
4894 
4895 		/*
4896 		 * set EOF bit for last buffer of HDLC frame or
4897 		 * for every buffer in raw mode
4898 		 */
4899 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4900 		    info->params.mode == MGSL_MODE_RAW)
4901 			set_desc_eof(*d, 1);
4902 		else
4903 			set_desc_eof(*d, 0);
4904 
4905 		/* set descriptor count for all but first buffer */
4906 		if (i != info->tbuf_start)
4907 			set_desc_count(*d, count);
4908 		d->buf_count = count;
4909 
4910 		if (++i == info->tbuf_count)
4911 			i = 0;
4912 	}
4913 
4914 	info->tbuf_current = i;
4915 
4916 	/* set first buffer count to make new data visible to DMA controller */
4917 	d = &info->tbufs[info->tbuf_start];
4918 	set_desc_count(*d, d->buf_count);
4919 
4920 	/* start transmitter if needed and update transmit timeout */
4921 	if (!info->tx_active)
4922 		tx_start(info);
4923 	update_tx_timer(info);
4924 
4925 	return true;
4926 }
4927 
4928 static int register_test(struct slgt_info *info)
4929 {
4930 	static unsigned short patterns[] =
4931 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4932 	static unsigned int count = ARRAY_SIZE(patterns);
4933 	unsigned int i;
4934 	int rc = 0;
4935 
4936 	for (i=0 ; i < count ; i++) {
4937 		wr_reg16(info, TIR, patterns[i]);
4938 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4939 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4940 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4941 			rc = -ENODEV;
4942 			break;
4943 		}
4944 	}
4945 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4946 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4947 	return rc;
4948 }
4949 
4950 static int irq_test(struct slgt_info *info)
4951 {
4952 	unsigned long timeout;
4953 	unsigned long flags;
4954 	struct tty_struct *oldtty = info->port.tty;
4955 	u32 speed = info->params.data_rate;
4956 
4957 	info->params.data_rate = 921600;
4958 	info->port.tty = NULL;
4959 
4960 	spin_lock_irqsave(&info->lock, flags);
4961 	async_mode(info);
4962 	slgt_irq_on(info, IRQ_TXIDLE);
4963 
4964 	/* enable transmitter */
4965 	wr_reg16(info, TCR,
4966 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4967 
4968 	/* write one byte and wait for tx idle */
4969 	wr_reg16(info, TDR, 0);
4970 
4971 	/* assume failure */
4972 	info->init_error = DiagStatus_IrqFailure;
4973 	info->irq_occurred = false;
4974 
4975 	spin_unlock_irqrestore(&info->lock, flags);
4976 
4977 	timeout=100;
4978 	while(timeout-- && !info->irq_occurred)
4979 		msleep_interruptible(10);
4980 
4981 	spin_lock_irqsave(&info->lock,flags);
4982 	reset_port(info);
4983 	spin_unlock_irqrestore(&info->lock,flags);
4984 
4985 	info->params.data_rate = speed;
4986 	info->port.tty = oldtty;
4987 
4988 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4989 	return info->irq_occurred ? 0 : -ENODEV;
4990 }
4991 
4992 static int loopback_test_rx(struct slgt_info *info)
4993 {
4994 	unsigned char *src, *dest;
4995 	int count;
4996 
4997 	if (desc_complete(info->rbufs[0])) {
4998 		count = desc_count(info->rbufs[0]);
4999 		src   = info->rbufs[0].buf;
5000 		dest  = info->tmp_rbuf;
5001 
5002 		for( ; count ; count-=2, src+=2) {
5003 			/* src=data byte (src+1)=status byte */
5004 			if (!(*(src+1) & (BIT9 + BIT8))) {
5005 				*dest = *src;
5006 				dest++;
5007 				info->tmp_rbuf_count++;
5008 			}
5009 		}
5010 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5011 		return 1;
5012 	}
5013 	return 0;
5014 }
5015 
5016 static int loopback_test(struct slgt_info *info)
5017 {
5018 #define TESTFRAMESIZE 20
5019 
5020 	unsigned long timeout;
5021 	u16 count = TESTFRAMESIZE;
5022 	unsigned char buf[TESTFRAMESIZE];
5023 	int rc = -ENODEV;
5024 	unsigned long flags;
5025 
5026 	struct tty_struct *oldtty = info->port.tty;
5027 	MGSL_PARAMS params;
5028 
5029 	memcpy(&params, &info->params, sizeof(params));
5030 
5031 	info->params.mode = MGSL_MODE_ASYNC;
5032 	info->params.data_rate = 921600;
5033 	info->params.loopback = 1;
5034 	info->port.tty = NULL;
5035 
5036 	/* build and send transmit frame */
5037 	for (count = 0; count < TESTFRAMESIZE; ++count)
5038 		buf[count] = (unsigned char)count;
5039 
5040 	info->tmp_rbuf_count = 0;
5041 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5042 
5043 	/* program hardware for HDLC and enabled receiver */
5044 	spin_lock_irqsave(&info->lock,flags);
5045 	async_mode(info);
5046 	rx_start(info);
5047 	tx_load(info, buf, count);
5048 	spin_unlock_irqrestore(&info->lock, flags);
5049 
5050 	/* wait for receive complete */
5051 	for (timeout = 100; timeout; --timeout) {
5052 		msleep_interruptible(10);
5053 		if (loopback_test_rx(info)) {
5054 			rc = 0;
5055 			break;
5056 		}
5057 	}
5058 
5059 	/* verify received frame length and contents */
5060 	if (!rc && (info->tmp_rbuf_count != count ||
5061 		  memcmp(buf, info->tmp_rbuf, count))) {
5062 		rc = -ENODEV;
5063 	}
5064 
5065 	spin_lock_irqsave(&info->lock,flags);
5066 	reset_adapter(info);
5067 	spin_unlock_irqrestore(&info->lock,flags);
5068 
5069 	memcpy(&info->params, &params, sizeof(info->params));
5070 	info->port.tty = oldtty;
5071 
5072 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5073 	return rc;
5074 }
5075 
5076 static int adapter_test(struct slgt_info *info)
5077 {
5078 	DBGINFO(("testing %s\n", info->device_name));
5079 	if (register_test(info) < 0) {
5080 		printk("register test failure %s addr=%08X\n",
5081 			info->device_name, info->phys_reg_addr);
5082 	} else if (irq_test(info) < 0) {
5083 		printk("IRQ test failure %s IRQ=%d\n",
5084 			info->device_name, info->irq_level);
5085 	} else if (loopback_test(info) < 0) {
5086 		printk("loopback test failure %s\n", info->device_name);
5087 	}
5088 	return info->init_error;
5089 }
5090 
5091 /*
5092  * transmit timeout handler
5093  */
5094 static void tx_timeout(struct timer_list *t)
5095 {
5096 	struct slgt_info *info = from_timer(info, t, tx_timer);
5097 	unsigned long flags;
5098 
5099 	DBGINFO(("%s tx_timeout\n", info->device_name));
5100 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5101 		info->icount.txtimeout++;
5102 	}
5103 	spin_lock_irqsave(&info->lock,flags);
5104 	tx_stop(info);
5105 	spin_unlock_irqrestore(&info->lock,flags);
5106 
5107 #if SYNCLINK_GENERIC_HDLC
5108 	if (info->netcount)
5109 		hdlcdev_tx_done(info);
5110 	else
5111 #endif
5112 		bh_transmit(info);
5113 }
5114 
5115 /*
5116  * receive buffer polling timer
5117  */
5118 static void rx_timeout(struct timer_list *t)
5119 {
5120 	struct slgt_info *info = from_timer(info, t, rx_timer);
5121 	unsigned long flags;
5122 
5123 	DBGINFO(("%s rx_timeout\n", info->device_name));
5124 	spin_lock_irqsave(&info->lock, flags);
5125 	info->pending_bh |= BH_RECEIVE;
5126 	spin_unlock_irqrestore(&info->lock, flags);
5127 	bh_handler(&info->task);
5128 }
5129 
5130