xref: /openbmc/linux/drivers/tty/synclink_gt.c (revision be709d48)
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  * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1399  * set encoding and frame check sequence (FCS) options
1400  *
1401  * dev       pointer to network device structure
1402  * encoding  serial encoding setting
1403  * parity    FCS setting
1404  *
1405  * returns 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  * called by generic HDLC layer to send frame
1450  *
1451  * skb  socket buffer containing HDLC frame
1452  * dev  pointer to network device structure
1453  */
1454 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1455 				      struct net_device *dev)
1456 {
1457 	struct slgt_info *info = dev_to_port(dev);
1458 	unsigned long flags;
1459 
1460 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1461 
1462 	if (!skb->len)
1463 		return NETDEV_TX_OK;
1464 
1465 	/* stop sending until this frame completes */
1466 	netif_stop_queue(dev);
1467 
1468 	/* update network statistics */
1469 	dev->stats.tx_packets++;
1470 	dev->stats.tx_bytes += skb->len;
1471 
1472 	/* save start time for transmit timeout detection */
1473 	netif_trans_update(dev);
1474 
1475 	spin_lock_irqsave(&info->lock, flags);
1476 	tx_load(info, skb->data, skb->len);
1477 	spin_unlock_irqrestore(&info->lock, flags);
1478 
1479 	/* done with socket buffer, so free it */
1480 	dev_kfree_skb(skb);
1481 
1482 	return NETDEV_TX_OK;
1483 }
1484 
1485 /**
1486  * called by network layer when interface enabled
1487  * claim resources and initialize hardware
1488  *
1489  * dev  pointer to network device structure
1490  *
1491  * returns 0 if success, otherwise error code
1492  */
1493 static int hdlcdev_open(struct net_device *dev)
1494 {
1495 	struct slgt_info *info = dev_to_port(dev);
1496 	int rc;
1497 	unsigned long flags;
1498 
1499 	if (!try_module_get(THIS_MODULE))
1500 		return -EBUSY;
1501 
1502 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1503 
1504 	/* generic HDLC layer open processing */
1505 	rc = hdlc_open(dev);
1506 	if (rc)
1507 		return rc;
1508 
1509 	/* arbitrate between network and tty opens */
1510 	spin_lock_irqsave(&info->netlock, flags);
1511 	if (info->port.count != 0 || info->netcount != 0) {
1512 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1513 		spin_unlock_irqrestore(&info->netlock, flags);
1514 		return -EBUSY;
1515 	}
1516 	info->netcount=1;
1517 	spin_unlock_irqrestore(&info->netlock, flags);
1518 
1519 	/* claim resources and init adapter */
1520 	if ((rc = startup(info)) != 0) {
1521 		spin_lock_irqsave(&info->netlock, flags);
1522 		info->netcount=0;
1523 		spin_unlock_irqrestore(&info->netlock, flags);
1524 		return rc;
1525 	}
1526 
1527 	/* assert RTS and DTR, apply hardware settings */
1528 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1529 	program_hw(info);
1530 
1531 	/* enable network layer transmit */
1532 	netif_trans_update(dev);
1533 	netif_start_queue(dev);
1534 
1535 	/* inform generic HDLC layer of current DCD status */
1536 	spin_lock_irqsave(&info->lock, flags);
1537 	get_signals(info);
1538 	spin_unlock_irqrestore(&info->lock, flags);
1539 	if (info->signals & SerialSignal_DCD)
1540 		netif_carrier_on(dev);
1541 	else
1542 		netif_carrier_off(dev);
1543 	return 0;
1544 }
1545 
1546 /**
1547  * called by network layer when interface is disabled
1548  * shutdown hardware and release resources
1549  *
1550  * dev  pointer to network device structure
1551  *
1552  * returns 0 if success, otherwise error code
1553  */
1554 static int hdlcdev_close(struct net_device *dev)
1555 {
1556 	struct slgt_info *info = dev_to_port(dev);
1557 	unsigned long flags;
1558 
1559 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1560 
1561 	netif_stop_queue(dev);
1562 
1563 	/* shutdown adapter and release resources */
1564 	shutdown(info);
1565 
1566 	hdlc_close(dev);
1567 
1568 	spin_lock_irqsave(&info->netlock, flags);
1569 	info->netcount=0;
1570 	spin_unlock_irqrestore(&info->netlock, flags);
1571 
1572 	module_put(THIS_MODULE);
1573 	return 0;
1574 }
1575 
1576 /**
1577  * called by network layer to process IOCTL call to network device
1578  *
1579  * dev  pointer to network device structure
1580  * ifr  pointer to network interface request structure
1581  * cmd  IOCTL command code
1582  *
1583  * returns 0 if success, otherwise error code
1584  */
1585 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1586 {
1587 	const size_t size = sizeof(sync_serial_settings);
1588 	sync_serial_settings new_line;
1589 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1590 	struct slgt_info *info = dev_to_port(dev);
1591 	unsigned int flags;
1592 
1593 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1594 
1595 	/* return error if TTY interface open */
1596 	if (info->port.count)
1597 		return -EBUSY;
1598 
1599 	if (cmd != SIOCWANDEV)
1600 		return hdlc_ioctl(dev, ifr, cmd);
1601 
1602 	memset(&new_line, 0, sizeof(new_line));
1603 
1604 	switch(ifr->ifr_settings.type) {
1605 	case IF_GET_IFACE: /* return current sync_serial_settings */
1606 
1607 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1608 		if (ifr->ifr_settings.size < size) {
1609 			ifr->ifr_settings.size = size; /* data size wanted */
1610 			return -ENOBUFS;
1611 		}
1612 
1613 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1614 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1615 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1616 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1617 
1618 		switch (flags){
1619 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1620 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1621 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1622 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1623 		default: new_line.clock_type = CLOCK_DEFAULT;
1624 		}
1625 
1626 		new_line.clock_rate = info->params.clock_speed;
1627 		new_line.loopback   = info->params.loopback ? 1:0;
1628 
1629 		if (copy_to_user(line, &new_line, size))
1630 			return -EFAULT;
1631 		return 0;
1632 
1633 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1634 
1635 		if(!capable(CAP_NET_ADMIN))
1636 			return -EPERM;
1637 		if (copy_from_user(&new_line, line, size))
1638 			return -EFAULT;
1639 
1640 		switch (new_line.clock_type)
1641 		{
1642 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1643 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1644 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1645 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1646 		case CLOCK_DEFAULT:  flags = info->params.flags &
1647 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1648 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1649 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1650 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1651 		default: return -EINVAL;
1652 		}
1653 
1654 		if (new_line.loopback != 0 && new_line.loopback != 1)
1655 			return -EINVAL;
1656 
1657 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1658 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1659 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1660 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1661 		info->params.flags |= flags;
1662 
1663 		info->params.loopback = new_line.loopback;
1664 
1665 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1666 			info->params.clock_speed = new_line.clock_rate;
1667 		else
1668 			info->params.clock_speed = 0;
1669 
1670 		/* if network interface up, reprogram hardware */
1671 		if (info->netcount)
1672 			program_hw(info);
1673 		return 0;
1674 
1675 	default:
1676 		return hdlc_ioctl(dev, ifr, cmd);
1677 	}
1678 }
1679 
1680 /**
1681  * called by network layer when transmit timeout is detected
1682  *
1683  * dev  pointer to network device structure
1684  */
1685 static void hdlcdev_tx_timeout(struct net_device *dev)
1686 {
1687 	struct slgt_info *info = dev_to_port(dev);
1688 	unsigned long flags;
1689 
1690 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1691 
1692 	dev->stats.tx_errors++;
1693 	dev->stats.tx_aborted_errors++;
1694 
1695 	spin_lock_irqsave(&info->lock,flags);
1696 	tx_stop(info);
1697 	spin_unlock_irqrestore(&info->lock,flags);
1698 
1699 	netif_wake_queue(dev);
1700 }
1701 
1702 /**
1703  * called by device driver when transmit completes
1704  * reenable network layer transmit if stopped
1705  *
1706  * info  pointer to device instance information
1707  */
1708 static void hdlcdev_tx_done(struct slgt_info *info)
1709 {
1710 	if (netif_queue_stopped(info->netdev))
1711 		netif_wake_queue(info->netdev);
1712 }
1713 
1714 /**
1715  * called by device driver when frame received
1716  * pass frame to network layer
1717  *
1718  * info  pointer to device instance information
1719  * buf   pointer to buffer contianing frame data
1720  * size  count of data bytes in buf
1721  */
1722 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1723 {
1724 	struct sk_buff *skb = dev_alloc_skb(size);
1725 	struct net_device *dev = info->netdev;
1726 
1727 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1728 
1729 	if (skb == NULL) {
1730 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1731 		dev->stats.rx_dropped++;
1732 		return;
1733 	}
1734 
1735 	skb_put_data(skb, buf, size);
1736 
1737 	skb->protocol = hdlc_type_trans(skb, dev);
1738 
1739 	dev->stats.rx_packets++;
1740 	dev->stats.rx_bytes += size;
1741 
1742 	netif_rx(skb);
1743 }
1744 
1745 static const struct net_device_ops hdlcdev_ops = {
1746 	.ndo_open       = hdlcdev_open,
1747 	.ndo_stop       = hdlcdev_close,
1748 	.ndo_start_xmit = hdlc_start_xmit,
1749 	.ndo_do_ioctl   = hdlcdev_ioctl,
1750 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1751 };
1752 
1753 /**
1754  * called by device driver when adding device instance
1755  * do generic HDLC initialization
1756  *
1757  * info  pointer to device instance information
1758  *
1759  * returns 0 if success, otherwise error code
1760  */
1761 static int hdlcdev_init(struct slgt_info *info)
1762 {
1763 	int rc;
1764 	struct net_device *dev;
1765 	hdlc_device *hdlc;
1766 
1767 	/* allocate and initialize network and HDLC layer objects */
1768 
1769 	dev = alloc_hdlcdev(info);
1770 	if (!dev) {
1771 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1772 		return -ENOMEM;
1773 	}
1774 
1775 	/* for network layer reporting purposes only */
1776 	dev->mem_start = info->phys_reg_addr;
1777 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1778 	dev->irq       = info->irq_level;
1779 
1780 	/* network layer callbacks and settings */
1781 	dev->netdev_ops	    = &hdlcdev_ops;
1782 	dev->watchdog_timeo = 10 * HZ;
1783 	dev->tx_queue_len   = 50;
1784 
1785 	/* generic HDLC layer callbacks and settings */
1786 	hdlc         = dev_to_hdlc(dev);
1787 	hdlc->attach = hdlcdev_attach;
1788 	hdlc->xmit   = hdlcdev_xmit;
1789 
1790 	/* register objects with HDLC layer */
1791 	rc = register_hdlc_device(dev);
1792 	if (rc) {
1793 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1794 		free_netdev(dev);
1795 		return rc;
1796 	}
1797 
1798 	info->netdev = dev;
1799 	return 0;
1800 }
1801 
1802 /**
1803  * called by device driver when removing device instance
1804  * do generic HDLC cleanup
1805  *
1806  * info  pointer to device instance information
1807  */
1808 static void hdlcdev_exit(struct slgt_info *info)
1809 {
1810 	unregister_hdlc_device(info->netdev);
1811 	free_netdev(info->netdev);
1812 	info->netdev = NULL;
1813 }
1814 
1815 #endif /* ifdef CONFIG_HDLC */
1816 
1817 /*
1818  * get async data from rx DMA buffers
1819  */
1820 static void rx_async(struct slgt_info *info)
1821 {
1822  	struct mgsl_icount *icount = &info->icount;
1823 	unsigned int start, end;
1824 	unsigned char *p;
1825 	unsigned char status;
1826 	struct slgt_desc *bufs = info->rbufs;
1827 	int i, count;
1828 	int chars = 0;
1829 	int stat;
1830 	unsigned char ch;
1831 
1832 	start = end = info->rbuf_current;
1833 
1834 	while(desc_complete(bufs[end])) {
1835 		count = desc_count(bufs[end]) - info->rbuf_index;
1836 		p     = bufs[end].buf + info->rbuf_index;
1837 
1838 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1839 		DBGDATA(info, p, count, "rx");
1840 
1841 		for(i=0 ; i < count; i+=2, p+=2) {
1842 			ch = *p;
1843 			icount->rx++;
1844 
1845 			stat = 0;
1846 
1847 			status = *(p + 1) & (BIT1 + BIT0);
1848 			if (status) {
1849 				if (status & BIT1)
1850 					icount->parity++;
1851 				else if (status & BIT0)
1852 					icount->frame++;
1853 				/* discard char if tty control flags say so */
1854 				if (status & info->ignore_status_mask)
1855 					continue;
1856 				if (status & BIT1)
1857 					stat = TTY_PARITY;
1858 				else if (status & BIT0)
1859 					stat = TTY_FRAME;
1860 			}
1861 			tty_insert_flip_char(&info->port, ch, stat);
1862 			chars++;
1863 		}
1864 
1865 		if (i < count) {
1866 			/* receive buffer not completed */
1867 			info->rbuf_index += i;
1868 			mod_timer(&info->rx_timer, jiffies + 1);
1869 			break;
1870 		}
1871 
1872 		info->rbuf_index = 0;
1873 		free_rbufs(info, end, end);
1874 
1875 		if (++end == info->rbuf_count)
1876 			end = 0;
1877 
1878 		/* if entire list searched then no frame available */
1879 		if (end == start)
1880 			break;
1881 	}
1882 
1883 	if (chars)
1884 		tty_flip_buffer_push(&info->port);
1885 }
1886 
1887 /*
1888  * return next bottom half action to perform
1889  */
1890 static int bh_action(struct slgt_info *info)
1891 {
1892 	unsigned long flags;
1893 	int rc;
1894 
1895 	spin_lock_irqsave(&info->lock,flags);
1896 
1897 	if (info->pending_bh & BH_RECEIVE) {
1898 		info->pending_bh &= ~BH_RECEIVE;
1899 		rc = BH_RECEIVE;
1900 	} else if (info->pending_bh & BH_TRANSMIT) {
1901 		info->pending_bh &= ~BH_TRANSMIT;
1902 		rc = BH_TRANSMIT;
1903 	} else if (info->pending_bh & BH_STATUS) {
1904 		info->pending_bh &= ~BH_STATUS;
1905 		rc = BH_STATUS;
1906 	} else {
1907 		/* Mark BH routine as complete */
1908 		info->bh_running = false;
1909 		info->bh_requested = false;
1910 		rc = 0;
1911 	}
1912 
1913 	spin_unlock_irqrestore(&info->lock,flags);
1914 
1915 	return rc;
1916 }
1917 
1918 /*
1919  * perform bottom half processing
1920  */
1921 static void bh_handler(struct work_struct *work)
1922 {
1923 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1924 	int action;
1925 
1926 	info->bh_running = true;
1927 
1928 	while((action = bh_action(info))) {
1929 		switch (action) {
1930 		case BH_RECEIVE:
1931 			DBGBH(("%s bh receive\n", info->device_name));
1932 			switch(info->params.mode) {
1933 			case MGSL_MODE_ASYNC:
1934 				rx_async(info);
1935 				break;
1936 			case MGSL_MODE_HDLC:
1937 				while(rx_get_frame(info));
1938 				break;
1939 			case MGSL_MODE_RAW:
1940 			case MGSL_MODE_MONOSYNC:
1941 			case MGSL_MODE_BISYNC:
1942 			case MGSL_MODE_XSYNC:
1943 				while(rx_get_buf(info));
1944 				break;
1945 			}
1946 			/* restart receiver if rx DMA buffers exhausted */
1947 			if (info->rx_restart)
1948 				rx_start(info);
1949 			break;
1950 		case BH_TRANSMIT:
1951 			bh_transmit(info);
1952 			break;
1953 		case BH_STATUS:
1954 			DBGBH(("%s bh status\n", info->device_name));
1955 			info->ri_chkcount = 0;
1956 			info->dsr_chkcount = 0;
1957 			info->dcd_chkcount = 0;
1958 			info->cts_chkcount = 0;
1959 			break;
1960 		default:
1961 			DBGBH(("%s unknown action\n", info->device_name));
1962 			break;
1963 		}
1964 	}
1965 	DBGBH(("%s bh_handler exit\n", info->device_name));
1966 }
1967 
1968 static void bh_transmit(struct slgt_info *info)
1969 {
1970 	struct tty_struct *tty = info->port.tty;
1971 
1972 	DBGBH(("%s bh_transmit\n", info->device_name));
1973 	if (tty)
1974 		tty_wakeup(tty);
1975 }
1976 
1977 static void dsr_change(struct slgt_info *info, unsigned short status)
1978 {
1979 	if (status & BIT3) {
1980 		info->signals |= SerialSignal_DSR;
1981 		info->input_signal_events.dsr_up++;
1982 	} else {
1983 		info->signals &= ~SerialSignal_DSR;
1984 		info->input_signal_events.dsr_down++;
1985 	}
1986 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1987 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1988 		slgt_irq_off(info, IRQ_DSR);
1989 		return;
1990 	}
1991 	info->icount.dsr++;
1992 	wake_up_interruptible(&info->status_event_wait_q);
1993 	wake_up_interruptible(&info->event_wait_q);
1994 	info->pending_bh |= BH_STATUS;
1995 }
1996 
1997 static void cts_change(struct slgt_info *info, unsigned short status)
1998 {
1999 	if (status & BIT2) {
2000 		info->signals |= SerialSignal_CTS;
2001 		info->input_signal_events.cts_up++;
2002 	} else {
2003 		info->signals &= ~SerialSignal_CTS;
2004 		info->input_signal_events.cts_down++;
2005 	}
2006 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
2007 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2008 		slgt_irq_off(info, IRQ_CTS);
2009 		return;
2010 	}
2011 	info->icount.cts++;
2012 	wake_up_interruptible(&info->status_event_wait_q);
2013 	wake_up_interruptible(&info->event_wait_q);
2014 	info->pending_bh |= BH_STATUS;
2015 
2016 	if (tty_port_cts_enabled(&info->port)) {
2017 		if (info->port.tty) {
2018 			if (info->port.tty->hw_stopped) {
2019 				if (info->signals & SerialSignal_CTS) {
2020 		 			info->port.tty->hw_stopped = 0;
2021 					info->pending_bh |= BH_TRANSMIT;
2022 					return;
2023 				}
2024 			} else {
2025 				if (!(info->signals & SerialSignal_CTS))
2026 		 			info->port.tty->hw_stopped = 1;
2027 			}
2028 		}
2029 	}
2030 }
2031 
2032 static void dcd_change(struct slgt_info *info, unsigned short status)
2033 {
2034 	if (status & BIT1) {
2035 		info->signals |= SerialSignal_DCD;
2036 		info->input_signal_events.dcd_up++;
2037 	} else {
2038 		info->signals &= ~SerialSignal_DCD;
2039 		info->input_signal_events.dcd_down++;
2040 	}
2041 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
2042 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2043 		slgt_irq_off(info, IRQ_DCD);
2044 		return;
2045 	}
2046 	info->icount.dcd++;
2047 #if SYNCLINK_GENERIC_HDLC
2048 	if (info->netcount) {
2049 		if (info->signals & SerialSignal_DCD)
2050 			netif_carrier_on(info->netdev);
2051 		else
2052 			netif_carrier_off(info->netdev);
2053 	}
2054 #endif
2055 	wake_up_interruptible(&info->status_event_wait_q);
2056 	wake_up_interruptible(&info->event_wait_q);
2057 	info->pending_bh |= BH_STATUS;
2058 
2059 	if (tty_port_check_carrier(&info->port)) {
2060 		if (info->signals & SerialSignal_DCD)
2061 			wake_up_interruptible(&info->port.open_wait);
2062 		else {
2063 			if (info->port.tty)
2064 				tty_hangup(info->port.tty);
2065 		}
2066 	}
2067 }
2068 
2069 static void ri_change(struct slgt_info *info, unsigned short status)
2070 {
2071 	if (status & BIT0) {
2072 		info->signals |= SerialSignal_RI;
2073 		info->input_signal_events.ri_up++;
2074 	} else {
2075 		info->signals &= ~SerialSignal_RI;
2076 		info->input_signal_events.ri_down++;
2077 	}
2078 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2079 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2080 		slgt_irq_off(info, IRQ_RI);
2081 		return;
2082 	}
2083 	info->icount.rng++;
2084 	wake_up_interruptible(&info->status_event_wait_q);
2085 	wake_up_interruptible(&info->event_wait_q);
2086 	info->pending_bh |= BH_STATUS;
2087 }
2088 
2089 static void isr_rxdata(struct slgt_info *info)
2090 {
2091 	unsigned int count = info->rbuf_fill_count;
2092 	unsigned int i = info->rbuf_fill_index;
2093 	unsigned short reg;
2094 
2095 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2096 		reg = rd_reg16(info, RDR);
2097 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2098 		if (desc_complete(info->rbufs[i])) {
2099 			/* all buffers full */
2100 			rx_stop(info);
2101 			info->rx_restart = 1;
2102 			continue;
2103 		}
2104 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2105 		/* async mode saves status byte to buffer for each data byte */
2106 		if (info->params.mode == MGSL_MODE_ASYNC)
2107 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2108 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2109 			/* buffer full or end of frame */
2110 			set_desc_count(info->rbufs[i], count);
2111 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2112 			info->rbuf_fill_count = count = 0;
2113 			if (++i == info->rbuf_count)
2114 				i = 0;
2115 			info->pending_bh |= BH_RECEIVE;
2116 		}
2117 	}
2118 
2119 	info->rbuf_fill_index = i;
2120 	info->rbuf_fill_count = count;
2121 }
2122 
2123 static void isr_serial(struct slgt_info *info)
2124 {
2125 	unsigned short status = rd_reg16(info, SSR);
2126 
2127 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2128 
2129 	wr_reg16(info, SSR, status); /* clear pending */
2130 
2131 	info->irq_occurred = true;
2132 
2133 	if (info->params.mode == MGSL_MODE_ASYNC) {
2134 		if (status & IRQ_TXIDLE) {
2135 			if (info->tx_active)
2136 				isr_txeom(info, status);
2137 		}
2138 		if (info->rx_pio && (status & IRQ_RXDATA))
2139 			isr_rxdata(info);
2140 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2141 			info->icount.brk++;
2142 			/* process break detection if tty control allows */
2143 			if (info->port.tty) {
2144 				if (!(status & info->ignore_status_mask)) {
2145 					if (info->read_status_mask & MASK_BREAK) {
2146 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2147 						if (info->port.flags & ASYNC_SAK)
2148 							do_SAK(info->port.tty);
2149 					}
2150 				}
2151 			}
2152 		}
2153 	} else {
2154 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2155 			isr_txeom(info, status);
2156 		if (info->rx_pio && (status & IRQ_RXDATA))
2157 			isr_rxdata(info);
2158 		if (status & IRQ_RXIDLE) {
2159 			if (status & RXIDLE)
2160 				info->icount.rxidle++;
2161 			else
2162 				info->icount.exithunt++;
2163 			wake_up_interruptible(&info->event_wait_q);
2164 		}
2165 
2166 		if (status & IRQ_RXOVER)
2167 			rx_start(info);
2168 	}
2169 
2170 	if (status & IRQ_DSR)
2171 		dsr_change(info, status);
2172 	if (status & IRQ_CTS)
2173 		cts_change(info, status);
2174 	if (status & IRQ_DCD)
2175 		dcd_change(info, status);
2176 	if (status & IRQ_RI)
2177 		ri_change(info, status);
2178 }
2179 
2180 static void isr_rdma(struct slgt_info *info)
2181 {
2182 	unsigned int status = rd_reg32(info, RDCSR);
2183 
2184 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2185 
2186 	/* RDCSR (rx DMA control/status)
2187 	 *
2188 	 * 31..07  reserved
2189 	 * 06      save status byte to DMA buffer
2190 	 * 05      error
2191 	 * 04      eol (end of list)
2192 	 * 03      eob (end of buffer)
2193 	 * 02      IRQ enable
2194 	 * 01      reset
2195 	 * 00      enable
2196 	 */
2197 	wr_reg32(info, RDCSR, status);	/* clear pending */
2198 
2199 	if (status & (BIT5 + BIT4)) {
2200 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2201 		info->rx_restart = true;
2202 	}
2203 	info->pending_bh |= BH_RECEIVE;
2204 }
2205 
2206 static void isr_tdma(struct slgt_info *info)
2207 {
2208 	unsigned int status = rd_reg32(info, TDCSR);
2209 
2210 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2211 
2212 	/* TDCSR (tx DMA control/status)
2213 	 *
2214 	 * 31..06  reserved
2215 	 * 05      error
2216 	 * 04      eol (end of list)
2217 	 * 03      eob (end of buffer)
2218 	 * 02      IRQ enable
2219 	 * 01      reset
2220 	 * 00      enable
2221 	 */
2222 	wr_reg32(info, TDCSR, status);	/* clear pending */
2223 
2224 	if (status & (BIT5 + BIT4 + BIT3)) {
2225 		// another transmit buffer has completed
2226 		// run bottom half to get more send data from user
2227 		info->pending_bh |= BH_TRANSMIT;
2228 	}
2229 }
2230 
2231 /*
2232  * return true if there are unsent tx DMA buffers, otherwise false
2233  *
2234  * if there are unsent buffers then info->tbuf_start
2235  * is set to index of first unsent buffer
2236  */
2237 static bool unsent_tbufs(struct slgt_info *info)
2238 {
2239 	unsigned int i = info->tbuf_current;
2240 	bool rc = false;
2241 
2242 	/*
2243 	 * search backwards from last loaded buffer (precedes tbuf_current)
2244 	 * for first unsent buffer (desc_count > 0)
2245 	 */
2246 
2247 	do {
2248 		if (i)
2249 			i--;
2250 		else
2251 			i = info->tbuf_count - 1;
2252 		if (!desc_count(info->tbufs[i]))
2253 			break;
2254 		info->tbuf_start = i;
2255 		rc = true;
2256 	} while (i != info->tbuf_current);
2257 
2258 	return rc;
2259 }
2260 
2261 static void isr_txeom(struct slgt_info *info, unsigned short status)
2262 {
2263 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2264 
2265 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2266 	tdma_reset(info);
2267 	if (status & IRQ_TXUNDER) {
2268 		unsigned short val = rd_reg16(info, TCR);
2269 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2270 		wr_reg16(info, TCR, val); /* clear reset bit */
2271 	}
2272 
2273 	if (info->tx_active) {
2274 		if (info->params.mode != MGSL_MODE_ASYNC) {
2275 			if (status & IRQ_TXUNDER)
2276 				info->icount.txunder++;
2277 			else if (status & IRQ_TXIDLE)
2278 				info->icount.txok++;
2279 		}
2280 
2281 		if (unsent_tbufs(info)) {
2282 			tx_start(info);
2283 			update_tx_timer(info);
2284 			return;
2285 		}
2286 		info->tx_active = false;
2287 
2288 		del_timer(&info->tx_timer);
2289 
2290 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2291 			info->signals &= ~SerialSignal_RTS;
2292 			info->drop_rts_on_tx_done = false;
2293 			set_signals(info);
2294 		}
2295 
2296 #if SYNCLINK_GENERIC_HDLC
2297 		if (info->netcount)
2298 			hdlcdev_tx_done(info);
2299 		else
2300 #endif
2301 		{
2302 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2303 				tx_stop(info);
2304 				return;
2305 			}
2306 			info->pending_bh |= BH_TRANSMIT;
2307 		}
2308 	}
2309 }
2310 
2311 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2312 {
2313 	struct cond_wait *w, *prev;
2314 
2315 	/* wake processes waiting for specific transitions */
2316 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2317 		if (w->data & changed) {
2318 			w->data = state;
2319 			wake_up_interruptible(&w->q);
2320 			if (prev != NULL)
2321 				prev->next = w->next;
2322 			else
2323 				info->gpio_wait_q = w->next;
2324 		} else
2325 			prev = w;
2326 	}
2327 }
2328 
2329 /* interrupt service routine
2330  *
2331  * 	irq	interrupt number
2332  * 	dev_id	device ID supplied during interrupt registration
2333  */
2334 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2335 {
2336 	struct slgt_info *info = dev_id;
2337 	unsigned int gsr;
2338 	unsigned int i;
2339 
2340 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2341 
2342 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2343 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2344 		info->irq_occurred = true;
2345 		for(i=0; i < info->port_count ; i++) {
2346 			if (info->port_array[i] == NULL)
2347 				continue;
2348 			spin_lock(&info->port_array[i]->lock);
2349 			if (gsr & (BIT8 << i))
2350 				isr_serial(info->port_array[i]);
2351 			if (gsr & (BIT16 << (i*2)))
2352 				isr_rdma(info->port_array[i]);
2353 			if (gsr & (BIT17 << (i*2)))
2354 				isr_tdma(info->port_array[i]);
2355 			spin_unlock(&info->port_array[i]->lock);
2356 		}
2357 	}
2358 
2359 	if (info->gpio_present) {
2360 		unsigned int state;
2361 		unsigned int changed;
2362 		spin_lock(&info->lock);
2363 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2364 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2365 			/* read latched state of GPIO signals */
2366 			state = rd_reg32(info, IOVR);
2367 			/* clear pending GPIO interrupt bits */
2368 			wr_reg32(info, IOSR, changed);
2369 			for (i=0 ; i < info->port_count ; i++) {
2370 				if (info->port_array[i] != NULL)
2371 					isr_gpio(info->port_array[i], changed, state);
2372 			}
2373 		}
2374 		spin_unlock(&info->lock);
2375 	}
2376 
2377 	for(i=0; i < info->port_count ; i++) {
2378 		struct slgt_info *port = info->port_array[i];
2379 		if (port == NULL)
2380 			continue;
2381 		spin_lock(&port->lock);
2382 		if ((port->port.count || port->netcount) &&
2383 		    port->pending_bh && !port->bh_running &&
2384 		    !port->bh_requested) {
2385 			DBGISR(("%s bh queued\n", port->device_name));
2386 			schedule_work(&port->task);
2387 			port->bh_requested = true;
2388 		}
2389 		spin_unlock(&port->lock);
2390 	}
2391 
2392 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2393 	return IRQ_HANDLED;
2394 }
2395 
2396 static int startup(struct slgt_info *info)
2397 {
2398 	DBGINFO(("%s startup\n", info->device_name));
2399 
2400 	if (tty_port_initialized(&info->port))
2401 		return 0;
2402 
2403 	if (!info->tx_buf) {
2404 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2405 		if (!info->tx_buf) {
2406 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2407 			return -ENOMEM;
2408 		}
2409 	}
2410 
2411 	info->pending_bh = 0;
2412 
2413 	memset(&info->icount, 0, sizeof(info->icount));
2414 
2415 	/* program hardware for current parameters */
2416 	change_params(info);
2417 
2418 	if (info->port.tty)
2419 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2420 
2421 	tty_port_set_initialized(&info->port, 1);
2422 
2423 	return 0;
2424 }
2425 
2426 /*
2427  *  called by close() and hangup() to shutdown hardware
2428  */
2429 static void shutdown(struct slgt_info *info)
2430 {
2431 	unsigned long flags;
2432 
2433 	if (!tty_port_initialized(&info->port))
2434 		return;
2435 
2436 	DBGINFO(("%s shutdown\n", info->device_name));
2437 
2438 	/* clear status wait queue because status changes */
2439 	/* can't happen after shutting down the hardware */
2440 	wake_up_interruptible(&info->status_event_wait_q);
2441 	wake_up_interruptible(&info->event_wait_q);
2442 
2443 	del_timer_sync(&info->tx_timer);
2444 	del_timer_sync(&info->rx_timer);
2445 
2446 	kfree(info->tx_buf);
2447 	info->tx_buf = NULL;
2448 
2449 	spin_lock_irqsave(&info->lock,flags);
2450 
2451 	tx_stop(info);
2452 	rx_stop(info);
2453 
2454 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2455 
2456  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2457 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2458 		set_signals(info);
2459 	}
2460 
2461 	flush_cond_wait(&info->gpio_wait_q);
2462 
2463 	spin_unlock_irqrestore(&info->lock,flags);
2464 
2465 	if (info->port.tty)
2466 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2467 
2468 	tty_port_set_initialized(&info->port, 0);
2469 }
2470 
2471 static void program_hw(struct slgt_info *info)
2472 {
2473 	unsigned long flags;
2474 
2475 	spin_lock_irqsave(&info->lock,flags);
2476 
2477 	rx_stop(info);
2478 	tx_stop(info);
2479 
2480 	if (info->params.mode != MGSL_MODE_ASYNC ||
2481 	    info->netcount)
2482 		sync_mode(info);
2483 	else
2484 		async_mode(info);
2485 
2486 	set_signals(info);
2487 
2488 	info->dcd_chkcount = 0;
2489 	info->cts_chkcount = 0;
2490 	info->ri_chkcount = 0;
2491 	info->dsr_chkcount = 0;
2492 
2493 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2494 	get_signals(info);
2495 
2496 	if (info->netcount ||
2497 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2498 		rx_start(info);
2499 
2500 	spin_unlock_irqrestore(&info->lock,flags);
2501 }
2502 
2503 /*
2504  * reconfigure adapter based on new parameters
2505  */
2506 static void change_params(struct slgt_info *info)
2507 {
2508 	unsigned cflag;
2509 	int bits_per_char;
2510 
2511 	if (!info->port.tty)
2512 		return;
2513 	DBGINFO(("%s change_params\n", info->device_name));
2514 
2515 	cflag = info->port.tty->termios.c_cflag;
2516 
2517 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2518 	/* otherwise assert RTS and DTR */
2519  	if (cflag & CBAUD)
2520 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2521 	else
2522 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2523 
2524 	/* byte size and parity */
2525 
2526 	switch (cflag & CSIZE) {
2527 	case CS5: info->params.data_bits = 5; break;
2528 	case CS6: info->params.data_bits = 6; break;
2529 	case CS7: info->params.data_bits = 7; break;
2530 	case CS8: info->params.data_bits = 8; break;
2531 	default:  info->params.data_bits = 7; break;
2532 	}
2533 
2534 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2535 
2536 	if (cflag & PARENB)
2537 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2538 	else
2539 		info->params.parity = ASYNC_PARITY_NONE;
2540 
2541 	/* calculate number of jiffies to transmit a full
2542 	 * FIFO (32 bytes) at specified data rate
2543 	 */
2544 	bits_per_char = info->params.data_bits +
2545 			info->params.stop_bits + 1;
2546 
2547 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2548 
2549 	if (info->params.data_rate) {
2550 		info->timeout = (32*HZ*bits_per_char) /
2551 				info->params.data_rate;
2552 	}
2553 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2554 
2555 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2556 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2557 
2558 	/* process tty input control flags */
2559 
2560 	info->read_status_mask = IRQ_RXOVER;
2561 	if (I_INPCK(info->port.tty))
2562 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2563  	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2564  		info->read_status_mask |= MASK_BREAK;
2565 	if (I_IGNPAR(info->port.tty))
2566 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2567 	if (I_IGNBRK(info->port.tty)) {
2568 		info->ignore_status_mask |= MASK_BREAK;
2569 		/* If ignoring parity and break indicators, ignore
2570 		 * overruns too.  (For real raw support).
2571 		 */
2572 		if (I_IGNPAR(info->port.tty))
2573 			info->ignore_status_mask |= MASK_OVERRUN;
2574 	}
2575 
2576 	program_hw(info);
2577 }
2578 
2579 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2580 {
2581 	DBGINFO(("%s get_stats\n",  info->device_name));
2582 	if (!user_icount) {
2583 		memset(&info->icount, 0, sizeof(info->icount));
2584 	} else {
2585 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2586 			return -EFAULT;
2587 	}
2588 	return 0;
2589 }
2590 
2591 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2592 {
2593 	DBGINFO(("%s get_params\n", info->device_name));
2594 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2595 		return -EFAULT;
2596 	return 0;
2597 }
2598 
2599 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2600 {
2601  	unsigned long flags;
2602 	MGSL_PARAMS tmp_params;
2603 
2604 	DBGINFO(("%s set_params\n", info->device_name));
2605 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2606 		return -EFAULT;
2607 
2608 	spin_lock_irqsave(&info->lock, flags);
2609 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2610 		info->base_clock = tmp_params.clock_speed;
2611 	else
2612 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2613 	spin_unlock_irqrestore(&info->lock, flags);
2614 
2615 	program_hw(info);
2616 
2617 	return 0;
2618 }
2619 
2620 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2621 {
2622 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2623 	if (put_user(info->idle_mode, idle_mode))
2624 		return -EFAULT;
2625 	return 0;
2626 }
2627 
2628 static int set_txidle(struct slgt_info *info, int idle_mode)
2629 {
2630  	unsigned long flags;
2631 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2632 	spin_lock_irqsave(&info->lock,flags);
2633 	info->idle_mode = idle_mode;
2634 	if (info->params.mode != MGSL_MODE_ASYNC)
2635 		tx_set_idle(info);
2636 	spin_unlock_irqrestore(&info->lock,flags);
2637 	return 0;
2638 }
2639 
2640 static int tx_enable(struct slgt_info *info, int enable)
2641 {
2642  	unsigned long flags;
2643 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2644 	spin_lock_irqsave(&info->lock,flags);
2645 	if (enable) {
2646 		if (!info->tx_enabled)
2647 			tx_start(info);
2648 	} else {
2649 		if (info->tx_enabled)
2650 			tx_stop(info);
2651 	}
2652 	spin_unlock_irqrestore(&info->lock,flags);
2653 	return 0;
2654 }
2655 
2656 /*
2657  * abort transmit HDLC frame
2658  */
2659 static int tx_abort(struct slgt_info *info)
2660 {
2661  	unsigned long flags;
2662 	DBGINFO(("%s tx_abort\n", info->device_name));
2663 	spin_lock_irqsave(&info->lock,flags);
2664 	tdma_reset(info);
2665 	spin_unlock_irqrestore(&info->lock,flags);
2666 	return 0;
2667 }
2668 
2669 static int rx_enable(struct slgt_info *info, int enable)
2670 {
2671  	unsigned long flags;
2672 	unsigned int rbuf_fill_level;
2673 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2674 	spin_lock_irqsave(&info->lock,flags);
2675 	/*
2676 	 * enable[31..16] = receive DMA buffer fill level
2677 	 * 0 = noop (leave fill level unchanged)
2678 	 * fill level must be multiple of 4 and <= buffer size
2679 	 */
2680 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2681 	if (rbuf_fill_level) {
2682 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2683 			spin_unlock_irqrestore(&info->lock, flags);
2684 			return -EINVAL;
2685 		}
2686 		info->rbuf_fill_level = rbuf_fill_level;
2687 		if (rbuf_fill_level < 128)
2688 			info->rx_pio = 1; /* PIO mode */
2689 		else
2690 			info->rx_pio = 0; /* DMA mode */
2691 		rx_stop(info); /* restart receiver to use new fill level */
2692 	}
2693 
2694 	/*
2695 	 * enable[1..0] = receiver enable command
2696 	 * 0 = disable
2697 	 * 1 = enable
2698 	 * 2 = enable or force hunt mode if already enabled
2699 	 */
2700 	enable &= 3;
2701 	if (enable) {
2702 		if (!info->rx_enabled)
2703 			rx_start(info);
2704 		else if (enable == 2) {
2705 			/* force hunt mode (write 1 to RCR[3]) */
2706 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2707 		}
2708 	} else {
2709 		if (info->rx_enabled)
2710 			rx_stop(info);
2711 	}
2712 	spin_unlock_irqrestore(&info->lock,flags);
2713 	return 0;
2714 }
2715 
2716 /*
2717  *  wait for specified event to occur
2718  */
2719 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2720 {
2721  	unsigned long flags;
2722 	int s;
2723 	int rc=0;
2724 	struct mgsl_icount cprev, cnow;
2725 	int events;
2726 	int mask;
2727 	struct	_input_signal_events oldsigs, newsigs;
2728 	DECLARE_WAITQUEUE(wait, current);
2729 
2730 	if (get_user(mask, mask_ptr))
2731 		return -EFAULT;
2732 
2733 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2734 
2735 	spin_lock_irqsave(&info->lock,flags);
2736 
2737 	/* return immediately if state matches requested events */
2738 	get_signals(info);
2739 	s = info->signals;
2740 
2741 	events = mask &
2742 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2743  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2744 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2745 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2746 	if (events) {
2747 		spin_unlock_irqrestore(&info->lock,flags);
2748 		goto exit;
2749 	}
2750 
2751 	/* save current irq counts */
2752 	cprev = info->icount;
2753 	oldsigs = info->input_signal_events;
2754 
2755 	/* enable hunt and idle irqs if needed */
2756 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2757 		unsigned short val = rd_reg16(info, SCR);
2758 		if (!(val & IRQ_RXIDLE))
2759 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2760 	}
2761 
2762 	set_current_state(TASK_INTERRUPTIBLE);
2763 	add_wait_queue(&info->event_wait_q, &wait);
2764 
2765 	spin_unlock_irqrestore(&info->lock,flags);
2766 
2767 	for(;;) {
2768 		schedule();
2769 		if (signal_pending(current)) {
2770 			rc = -ERESTARTSYS;
2771 			break;
2772 		}
2773 
2774 		/* get current irq counts */
2775 		spin_lock_irqsave(&info->lock,flags);
2776 		cnow = info->icount;
2777 		newsigs = info->input_signal_events;
2778 		set_current_state(TASK_INTERRUPTIBLE);
2779 		spin_unlock_irqrestore(&info->lock,flags);
2780 
2781 		/* if no change, wait aborted for some reason */
2782 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2783 		    newsigs.dsr_down == oldsigs.dsr_down &&
2784 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2785 		    newsigs.dcd_down == oldsigs.dcd_down &&
2786 		    newsigs.cts_up   == oldsigs.cts_up   &&
2787 		    newsigs.cts_down == oldsigs.cts_down &&
2788 		    newsigs.ri_up    == oldsigs.ri_up    &&
2789 		    newsigs.ri_down  == oldsigs.ri_down  &&
2790 		    cnow.exithunt    == cprev.exithunt   &&
2791 		    cnow.rxidle      == cprev.rxidle) {
2792 			rc = -EIO;
2793 			break;
2794 		}
2795 
2796 		events = mask &
2797 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2798 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2799 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2800 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2801 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2802 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2803 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2804 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2805 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2806 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2807 		if (events)
2808 			break;
2809 
2810 		cprev = cnow;
2811 		oldsigs = newsigs;
2812 	}
2813 
2814 	remove_wait_queue(&info->event_wait_q, &wait);
2815 	set_current_state(TASK_RUNNING);
2816 
2817 
2818 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2819 		spin_lock_irqsave(&info->lock,flags);
2820 		if (!waitqueue_active(&info->event_wait_q)) {
2821 			/* disable enable exit hunt mode/idle rcvd IRQs */
2822 			wr_reg16(info, SCR,
2823 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2824 		}
2825 		spin_unlock_irqrestore(&info->lock,flags);
2826 	}
2827 exit:
2828 	if (rc == 0)
2829 		rc = put_user(events, mask_ptr);
2830 	return rc;
2831 }
2832 
2833 static int get_interface(struct slgt_info *info, int __user *if_mode)
2834 {
2835 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2836 	if (put_user(info->if_mode, if_mode))
2837 		return -EFAULT;
2838 	return 0;
2839 }
2840 
2841 static int set_interface(struct slgt_info *info, int if_mode)
2842 {
2843  	unsigned long flags;
2844 	unsigned short val;
2845 
2846 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2847 	spin_lock_irqsave(&info->lock,flags);
2848 	info->if_mode = if_mode;
2849 
2850 	msc_set_vcr(info);
2851 
2852 	/* TCR (tx control) 07  1=RTS driver control */
2853 	val = rd_reg16(info, TCR);
2854 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2855 		val |= BIT7;
2856 	else
2857 		val &= ~BIT7;
2858 	wr_reg16(info, TCR, val);
2859 
2860 	spin_unlock_irqrestore(&info->lock,flags);
2861 	return 0;
2862 }
2863 
2864 static int get_xsync(struct slgt_info *info, int __user *xsync)
2865 {
2866 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2867 	if (put_user(info->xsync, xsync))
2868 		return -EFAULT;
2869 	return 0;
2870 }
2871 
2872 /*
2873  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2874  *
2875  * sync pattern is contained in least significant bytes of value
2876  * most significant byte of sync pattern is oldest (1st sent/detected)
2877  */
2878 static int set_xsync(struct slgt_info *info, int xsync)
2879 {
2880 	unsigned long flags;
2881 
2882 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2883 	spin_lock_irqsave(&info->lock, flags);
2884 	info->xsync = xsync;
2885 	wr_reg32(info, XSR, xsync);
2886 	spin_unlock_irqrestore(&info->lock, flags);
2887 	return 0;
2888 }
2889 
2890 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2891 {
2892 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2893 	if (put_user(info->xctrl, xctrl))
2894 		return -EFAULT;
2895 	return 0;
2896 }
2897 
2898 /*
2899  * set extended control options
2900  *
2901  * xctrl[31:19] reserved, must be zero
2902  * xctrl[18:17] extended sync pattern length in bytes
2903  *              00 = 1 byte  in xsr[7:0]
2904  *              01 = 2 bytes in xsr[15:0]
2905  *              10 = 3 bytes in xsr[23:0]
2906  *              11 = 4 bytes in xsr[31:0]
2907  * xctrl[16]    1 = enable terminal count, 0=disabled
2908  * xctrl[15:0]  receive terminal count for fixed length packets
2909  *              value is count minus one (0 = 1 byte packet)
2910  *              when terminal count is reached, receiver
2911  *              automatically returns to hunt mode and receive
2912  *              FIFO contents are flushed to DMA buffers with
2913  *              end of frame (EOF) status
2914  */
2915 static int set_xctrl(struct slgt_info *info, int xctrl)
2916 {
2917 	unsigned long flags;
2918 
2919 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2920 	spin_lock_irqsave(&info->lock, flags);
2921 	info->xctrl = xctrl;
2922 	wr_reg32(info, XCR, xctrl);
2923 	spin_unlock_irqrestore(&info->lock, flags);
2924 	return 0;
2925 }
2926 
2927 /*
2928  * set general purpose IO pin state and direction
2929  *
2930  * user_gpio fields:
2931  * state   each bit indicates a pin state
2932  * smask   set bit indicates pin state to set
2933  * dir     each bit indicates a pin direction (0=input, 1=output)
2934  * dmask   set bit indicates pin direction to set
2935  */
2936 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2937 {
2938  	unsigned long flags;
2939 	struct gpio_desc gpio;
2940 	__u32 data;
2941 
2942 	if (!info->gpio_present)
2943 		return -EINVAL;
2944 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2945 		return -EFAULT;
2946 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2947 		 info->device_name, gpio.state, gpio.smask,
2948 		 gpio.dir, gpio.dmask));
2949 
2950 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2951 	if (gpio.dmask) {
2952 		data = rd_reg32(info, IODR);
2953 		data |= gpio.dmask & gpio.dir;
2954 		data &= ~(gpio.dmask & ~gpio.dir);
2955 		wr_reg32(info, IODR, data);
2956 	}
2957 	if (gpio.smask) {
2958 		data = rd_reg32(info, IOVR);
2959 		data |= gpio.smask & gpio.state;
2960 		data &= ~(gpio.smask & ~gpio.state);
2961 		wr_reg32(info, IOVR, data);
2962 	}
2963 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2964 
2965 	return 0;
2966 }
2967 
2968 /*
2969  * get general purpose IO pin state and direction
2970  */
2971 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2972 {
2973 	struct gpio_desc gpio;
2974 	if (!info->gpio_present)
2975 		return -EINVAL;
2976 	gpio.state = rd_reg32(info, IOVR);
2977 	gpio.smask = 0xffffffff;
2978 	gpio.dir   = rd_reg32(info, IODR);
2979 	gpio.dmask = 0xffffffff;
2980 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2981 		return -EFAULT;
2982 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2983 		 info->device_name, gpio.state, gpio.dir));
2984 	return 0;
2985 }
2986 
2987 /*
2988  * conditional wait facility
2989  */
2990 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2991 {
2992 	init_waitqueue_head(&w->q);
2993 	init_waitqueue_entry(&w->wait, current);
2994 	w->data = data;
2995 }
2996 
2997 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2998 {
2999 	set_current_state(TASK_INTERRUPTIBLE);
3000 	add_wait_queue(&w->q, &w->wait);
3001 	w->next = *head;
3002 	*head = w;
3003 }
3004 
3005 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3006 {
3007 	struct cond_wait *w, *prev;
3008 	remove_wait_queue(&cw->q, &cw->wait);
3009 	set_current_state(TASK_RUNNING);
3010 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3011 		if (w == cw) {
3012 			if (prev != NULL)
3013 				prev->next = w->next;
3014 			else
3015 				*head = w->next;
3016 			break;
3017 		}
3018 	}
3019 }
3020 
3021 static void flush_cond_wait(struct cond_wait **head)
3022 {
3023 	while (*head != NULL) {
3024 		wake_up_interruptible(&(*head)->q);
3025 		*head = (*head)->next;
3026 	}
3027 }
3028 
3029 /*
3030  * wait for general purpose I/O pin(s) to enter specified state
3031  *
3032  * user_gpio fields:
3033  * state - bit indicates target pin state
3034  * smask - set bit indicates watched pin
3035  *
3036  * The wait ends when at least one watched pin enters the specified
3037  * state. When 0 (no error) is returned, user_gpio->state is set to the
3038  * state of all GPIO pins when the wait ends.
3039  *
3040  * Note: Each pin may be a dedicated input, dedicated output, or
3041  * configurable input/output. The number and configuration of pins
3042  * varies with the specific adapter model. Only input pins (dedicated
3043  * or configured) can be monitored with this function.
3044  */
3045 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3046 {
3047  	unsigned long flags;
3048 	int rc = 0;
3049 	struct gpio_desc gpio;
3050 	struct cond_wait wait;
3051 	u32 state;
3052 
3053 	if (!info->gpio_present)
3054 		return -EINVAL;
3055 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3056 		return -EFAULT;
3057 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3058 		 info->device_name, gpio.state, gpio.smask));
3059 	/* ignore output pins identified by set IODR bit */
3060 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3061 		return -EINVAL;
3062 	init_cond_wait(&wait, gpio.smask);
3063 
3064 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3065 	/* enable interrupts for watched pins */
3066 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3067 	/* get current pin states */
3068 	state = rd_reg32(info, IOVR);
3069 
3070 	if (gpio.smask & ~(state ^ gpio.state)) {
3071 		/* already in target state */
3072 		gpio.state = state;
3073 	} else {
3074 		/* wait for target state */
3075 		add_cond_wait(&info->gpio_wait_q, &wait);
3076 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3077 		schedule();
3078 		if (signal_pending(current))
3079 			rc = -ERESTARTSYS;
3080 		else
3081 			gpio.state = wait.data;
3082 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3083 		remove_cond_wait(&info->gpio_wait_q, &wait);
3084 	}
3085 
3086 	/* disable all GPIO interrupts if no waiting processes */
3087 	if (info->gpio_wait_q == NULL)
3088 		wr_reg32(info, IOER, 0);
3089 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3090 
3091 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3092 		rc = -EFAULT;
3093 	return rc;
3094 }
3095 
3096 static int modem_input_wait(struct slgt_info *info,int arg)
3097 {
3098  	unsigned long flags;
3099 	int rc;
3100 	struct mgsl_icount cprev, cnow;
3101 	DECLARE_WAITQUEUE(wait, current);
3102 
3103 	/* save current irq counts */
3104 	spin_lock_irqsave(&info->lock,flags);
3105 	cprev = info->icount;
3106 	add_wait_queue(&info->status_event_wait_q, &wait);
3107 	set_current_state(TASK_INTERRUPTIBLE);
3108 	spin_unlock_irqrestore(&info->lock,flags);
3109 
3110 	for(;;) {
3111 		schedule();
3112 		if (signal_pending(current)) {
3113 			rc = -ERESTARTSYS;
3114 			break;
3115 		}
3116 
3117 		/* get new irq counts */
3118 		spin_lock_irqsave(&info->lock,flags);
3119 		cnow = info->icount;
3120 		set_current_state(TASK_INTERRUPTIBLE);
3121 		spin_unlock_irqrestore(&info->lock,flags);
3122 
3123 		/* if no change, wait aborted for some reason */
3124 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3125 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3126 			rc = -EIO;
3127 			break;
3128 		}
3129 
3130 		/* check for change in caller specified modem input */
3131 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3132 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3133 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3134 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3135 			rc = 0;
3136 			break;
3137 		}
3138 
3139 		cprev = cnow;
3140 	}
3141 	remove_wait_queue(&info->status_event_wait_q, &wait);
3142 	set_current_state(TASK_RUNNING);
3143 	return rc;
3144 }
3145 
3146 /*
3147  *  return state of serial control and status signals
3148  */
3149 static int tiocmget(struct tty_struct *tty)
3150 {
3151 	struct slgt_info *info = tty->driver_data;
3152 	unsigned int result;
3153  	unsigned long flags;
3154 
3155 	spin_lock_irqsave(&info->lock,flags);
3156  	get_signals(info);
3157 	spin_unlock_irqrestore(&info->lock,flags);
3158 
3159 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3160 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3161 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3162 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3163 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3164 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3165 
3166 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3167 	return result;
3168 }
3169 
3170 /*
3171  * set modem control signals (DTR/RTS)
3172  *
3173  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3174  *		TIOCMSET = set/clear signal values
3175  * 	value	bit mask for command
3176  */
3177 static int tiocmset(struct tty_struct *tty,
3178 		    unsigned int set, unsigned int clear)
3179 {
3180 	struct slgt_info *info = tty->driver_data;
3181  	unsigned long flags;
3182 
3183 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3184 
3185 	if (set & TIOCM_RTS)
3186 		info->signals |= SerialSignal_RTS;
3187 	if (set & TIOCM_DTR)
3188 		info->signals |= SerialSignal_DTR;
3189 	if (clear & TIOCM_RTS)
3190 		info->signals &= ~SerialSignal_RTS;
3191 	if (clear & TIOCM_DTR)
3192 		info->signals &= ~SerialSignal_DTR;
3193 
3194 	spin_lock_irqsave(&info->lock,flags);
3195  	set_signals(info);
3196 	spin_unlock_irqrestore(&info->lock,flags);
3197 	return 0;
3198 }
3199 
3200 static int carrier_raised(struct tty_port *port)
3201 {
3202 	unsigned long flags;
3203 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3204 
3205 	spin_lock_irqsave(&info->lock,flags);
3206  	get_signals(info);
3207 	spin_unlock_irqrestore(&info->lock,flags);
3208 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3209 }
3210 
3211 static void dtr_rts(struct tty_port *port, int on)
3212 {
3213 	unsigned long flags;
3214 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3215 
3216 	spin_lock_irqsave(&info->lock,flags);
3217 	if (on)
3218 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3219 	else
3220 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3221  	set_signals(info);
3222 	spin_unlock_irqrestore(&info->lock,flags);
3223 }
3224 
3225 
3226 /*
3227  *  block current process until the device is ready to open
3228  */
3229 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3230 			   struct slgt_info *info)
3231 {
3232 	DECLARE_WAITQUEUE(wait, current);
3233 	int		retval;
3234 	bool		do_clocal = false;
3235 	unsigned long	flags;
3236 	int		cd;
3237 	struct tty_port *port = &info->port;
3238 
3239 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3240 
3241 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3242 		/* nonblock mode is set or port is not enabled */
3243 		tty_port_set_active(port, 1);
3244 		return 0;
3245 	}
3246 
3247 	if (C_CLOCAL(tty))
3248 		do_clocal = true;
3249 
3250 	/* Wait for carrier detect and the line to become
3251 	 * free (i.e., not in use by the callout).  While we are in
3252 	 * this loop, port->count is dropped by one, so that
3253 	 * close() knows when to free things.  We restore it upon
3254 	 * exit, either normal or abnormal.
3255 	 */
3256 
3257 	retval = 0;
3258 	add_wait_queue(&port->open_wait, &wait);
3259 
3260 	spin_lock_irqsave(&info->lock, flags);
3261 	port->count--;
3262 	spin_unlock_irqrestore(&info->lock, flags);
3263 	port->blocked_open++;
3264 
3265 	while (1) {
3266 		if (C_BAUD(tty) && tty_port_initialized(port))
3267 			tty_port_raise_dtr_rts(port);
3268 
3269 		set_current_state(TASK_INTERRUPTIBLE);
3270 
3271 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3272 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3273 					-EAGAIN : -ERESTARTSYS;
3274 			break;
3275 		}
3276 
3277 		cd = tty_port_carrier_raised(port);
3278 		if (do_clocal || cd)
3279 			break;
3280 
3281 		if (signal_pending(current)) {
3282 			retval = -ERESTARTSYS;
3283 			break;
3284 		}
3285 
3286 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3287 		tty_unlock(tty);
3288 		schedule();
3289 		tty_lock(tty);
3290 	}
3291 
3292 	set_current_state(TASK_RUNNING);
3293 	remove_wait_queue(&port->open_wait, &wait);
3294 
3295 	if (!tty_hung_up_p(filp))
3296 		port->count++;
3297 	port->blocked_open--;
3298 
3299 	if (!retval)
3300 		tty_port_set_active(port, 1);
3301 
3302 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3303 	return retval;
3304 }
3305 
3306 /*
3307  * allocate buffers used for calling line discipline receive_buf
3308  * directly in synchronous mode
3309  * note: add 5 bytes to max frame size to allow appending
3310  * 32-bit CRC and status byte when configured to do so
3311  */
3312 static int alloc_tmp_rbuf(struct slgt_info *info)
3313 {
3314 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3315 	if (info->tmp_rbuf == NULL)
3316 		return -ENOMEM;
3317 	/* unused flag buffer to satisfy receive_buf calling interface */
3318 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3319 	if (!info->flag_buf) {
3320 		kfree(info->tmp_rbuf);
3321 		info->tmp_rbuf = NULL;
3322 		return -ENOMEM;
3323 	}
3324 	return 0;
3325 }
3326 
3327 static void free_tmp_rbuf(struct slgt_info *info)
3328 {
3329 	kfree(info->tmp_rbuf);
3330 	info->tmp_rbuf = NULL;
3331 	kfree(info->flag_buf);
3332 	info->flag_buf = NULL;
3333 }
3334 
3335 /*
3336  * allocate DMA descriptor lists.
3337  */
3338 static int alloc_desc(struct slgt_info *info)
3339 {
3340 	unsigned int i;
3341 	unsigned int pbufs;
3342 
3343 	/* allocate memory to hold descriptor lists */
3344 	info->bufs = pci_zalloc_consistent(info->pdev, DESC_LIST_SIZE,
3345 					   &info->bufs_dma_addr);
3346 	if (info->bufs == NULL)
3347 		return -ENOMEM;
3348 
3349 	info->rbufs = (struct slgt_desc*)info->bufs;
3350 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3351 
3352 	pbufs = (unsigned int)info->bufs_dma_addr;
3353 
3354 	/*
3355 	 * Build circular lists of descriptors
3356 	 */
3357 
3358 	for (i=0; i < info->rbuf_count; i++) {
3359 		/* physical address of this descriptor */
3360 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3361 
3362 		/* physical address of next descriptor */
3363 		if (i == info->rbuf_count - 1)
3364 			info->rbufs[i].next = cpu_to_le32(pbufs);
3365 		else
3366 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3367 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3368 	}
3369 
3370 	for (i=0; i < info->tbuf_count; i++) {
3371 		/* physical address of this descriptor */
3372 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3373 
3374 		/* physical address of next descriptor */
3375 		if (i == info->tbuf_count - 1)
3376 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3377 		else
3378 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3379 	}
3380 
3381 	return 0;
3382 }
3383 
3384 static void free_desc(struct slgt_info *info)
3385 {
3386 	if (info->bufs != NULL) {
3387 		pci_free_consistent(info->pdev, DESC_LIST_SIZE, info->bufs, info->bufs_dma_addr);
3388 		info->bufs  = NULL;
3389 		info->rbufs = NULL;
3390 		info->tbufs = NULL;
3391 	}
3392 }
3393 
3394 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3395 {
3396 	int i;
3397 	for (i=0; i < count; i++) {
3398 		if ((bufs[i].buf = pci_alloc_consistent(info->pdev, DMABUFSIZE, &bufs[i].buf_dma_addr)) == NULL)
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 		pci_free_consistent(info->pdev, DMABUFSIZE, bufs[i].buf, bufs[i].buf_dma_addr);
3412 		bufs[i].buf = NULL;
3413 	}
3414 }
3415 
3416 static int alloc_dma_bufs(struct slgt_info *info)
3417 {
3418 	info->rbuf_count = 32;
3419 	info->tbuf_count = 32;
3420 
3421 	if (alloc_desc(info) < 0 ||
3422 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3423 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3424 	    alloc_tmp_rbuf(info) < 0) {
3425 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3426 		return -ENOMEM;
3427 	}
3428 	reset_rbufs(info);
3429 	return 0;
3430 }
3431 
3432 static void free_dma_bufs(struct slgt_info *info)
3433 {
3434 	if (info->bufs) {
3435 		free_bufs(info, info->rbufs, info->rbuf_count);
3436 		free_bufs(info, info->tbufs, info->tbuf_count);
3437 		free_desc(info);
3438 	}
3439 	free_tmp_rbuf(info);
3440 }
3441 
3442 static int claim_resources(struct slgt_info *info)
3443 {
3444 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3445 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3446 			info->device_name, info->phys_reg_addr));
3447 		info->init_error = DiagStatus_AddressConflict;
3448 		goto errout;
3449 	}
3450 	else
3451 		info->reg_addr_requested = true;
3452 
3453 	info->reg_addr = ioremap_nocache(info->phys_reg_addr, SLGT_REG_SIZE);
3454 	if (!info->reg_addr) {
3455 		DBGERR(("%s can't map device registers, addr=%08X\n",
3456 			info->device_name, info->phys_reg_addr));
3457 		info->init_error = DiagStatus_CantAssignPciResources;
3458 		goto errout;
3459 	}
3460 	return 0;
3461 
3462 errout:
3463 	release_resources(info);
3464 	return -ENODEV;
3465 }
3466 
3467 static void release_resources(struct slgt_info *info)
3468 {
3469 	if (info->irq_requested) {
3470 		free_irq(info->irq_level, info);
3471 		info->irq_requested = false;
3472 	}
3473 
3474 	if (info->reg_addr_requested) {
3475 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3476 		info->reg_addr_requested = false;
3477 	}
3478 
3479 	if (info->reg_addr) {
3480 		iounmap(info->reg_addr);
3481 		info->reg_addr = NULL;
3482 	}
3483 }
3484 
3485 /* Add the specified device instance data structure to the
3486  * global linked list of devices and increment the device count.
3487  */
3488 static void add_device(struct slgt_info *info)
3489 {
3490 	char *devstr;
3491 
3492 	info->next_device = NULL;
3493 	info->line = slgt_device_count;
3494 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3495 
3496 	if (info->line < MAX_DEVICES) {
3497 		if (maxframe[info->line])
3498 			info->max_frame_size = maxframe[info->line];
3499 	}
3500 
3501 	slgt_device_count++;
3502 
3503 	if (!slgt_device_list)
3504 		slgt_device_list = info;
3505 	else {
3506 		struct slgt_info *current_dev = slgt_device_list;
3507 		while(current_dev->next_device)
3508 			current_dev = current_dev->next_device;
3509 		current_dev->next_device = info;
3510 	}
3511 
3512 	if (info->max_frame_size < 4096)
3513 		info->max_frame_size = 4096;
3514 	else if (info->max_frame_size > 65535)
3515 		info->max_frame_size = 65535;
3516 
3517 	switch(info->pdev->device) {
3518 	case SYNCLINK_GT_DEVICE_ID:
3519 		devstr = "GT";
3520 		break;
3521 	case SYNCLINK_GT2_DEVICE_ID:
3522 		devstr = "GT2";
3523 		break;
3524 	case SYNCLINK_GT4_DEVICE_ID:
3525 		devstr = "GT4";
3526 		break;
3527 	case SYNCLINK_AC_DEVICE_ID:
3528 		devstr = "AC";
3529 		info->params.mode = MGSL_MODE_ASYNC;
3530 		break;
3531 	default:
3532 		devstr = "(unknown model)";
3533 	}
3534 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3535 		devstr, info->device_name, info->phys_reg_addr,
3536 		info->irq_level, info->max_frame_size);
3537 
3538 #if SYNCLINK_GENERIC_HDLC
3539 	hdlcdev_init(info);
3540 #endif
3541 }
3542 
3543 static const struct tty_port_operations slgt_port_ops = {
3544 	.carrier_raised = carrier_raised,
3545 	.dtr_rts = dtr_rts,
3546 };
3547 
3548 /*
3549  *  allocate device instance structure, return NULL on failure
3550  */
3551 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3552 {
3553 	struct slgt_info *info;
3554 
3555 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3556 
3557 	if (!info) {
3558 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3559 			driver_name, adapter_num, port_num));
3560 	} else {
3561 		tty_port_init(&info->port);
3562 		info->port.ops = &slgt_port_ops;
3563 		info->magic = MGSL_MAGIC;
3564 		INIT_WORK(&info->task, bh_handler);
3565 		info->max_frame_size = 4096;
3566 		info->base_clock = 14745600;
3567 		info->rbuf_fill_level = DMABUFSIZE;
3568 		info->port.close_delay = 5*HZ/10;
3569 		info->port.closing_wait = 30*HZ;
3570 		init_waitqueue_head(&info->status_event_wait_q);
3571 		init_waitqueue_head(&info->event_wait_q);
3572 		spin_lock_init(&info->netlock);
3573 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3574 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3575 		info->adapter_num = adapter_num;
3576 		info->port_num = port_num;
3577 
3578 		timer_setup(&info->tx_timer, tx_timeout, 0);
3579 		timer_setup(&info->rx_timer, rx_timeout, 0);
3580 
3581 		/* Copy configuration info to device instance data */
3582 		info->pdev = pdev;
3583 		info->irq_level = pdev->irq;
3584 		info->phys_reg_addr = pci_resource_start(pdev,0);
3585 
3586 		info->bus_type = MGSL_BUS_TYPE_PCI;
3587 		info->irq_flags = IRQF_SHARED;
3588 
3589 		info->init_error = -1; /* assume error, set to 0 on successful init */
3590 	}
3591 
3592 	return info;
3593 }
3594 
3595 static void device_init(int adapter_num, struct pci_dev *pdev)
3596 {
3597 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3598 	int i;
3599 	int port_count = 1;
3600 
3601 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3602 		port_count = 2;
3603 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3604 		port_count = 4;
3605 
3606 	/* allocate device instances for all ports */
3607 	for (i=0; i < port_count; ++i) {
3608 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3609 		if (port_array[i] == NULL) {
3610 			for (--i; i >= 0; --i) {
3611 				tty_port_destroy(&port_array[i]->port);
3612 				kfree(port_array[i]);
3613 			}
3614 			return;
3615 		}
3616 	}
3617 
3618 	/* give copy of port_array to all ports and add to device list  */
3619 	for (i=0; i < port_count; ++i) {
3620 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3621 		add_device(port_array[i]);
3622 		port_array[i]->port_count = port_count;
3623 		spin_lock_init(&port_array[i]->lock);
3624 	}
3625 
3626 	/* Allocate and claim adapter resources */
3627 	if (!claim_resources(port_array[0])) {
3628 
3629 		alloc_dma_bufs(port_array[0]);
3630 
3631 		/* copy resource information from first port to others */
3632 		for (i = 1; i < port_count; ++i) {
3633 			port_array[i]->irq_level = port_array[0]->irq_level;
3634 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3635 			alloc_dma_bufs(port_array[i]);
3636 		}
3637 
3638 		if (request_irq(port_array[0]->irq_level,
3639 					slgt_interrupt,
3640 					port_array[0]->irq_flags,
3641 					port_array[0]->device_name,
3642 					port_array[0]) < 0) {
3643 			DBGERR(("%s request_irq failed IRQ=%d\n",
3644 				port_array[0]->device_name,
3645 				port_array[0]->irq_level));
3646 		} else {
3647 			port_array[0]->irq_requested = true;
3648 			adapter_test(port_array[0]);
3649 			for (i=1 ; i < port_count ; i++) {
3650 				port_array[i]->init_error = port_array[0]->init_error;
3651 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3652 			}
3653 		}
3654 	}
3655 
3656 	for (i = 0; i < port_count; ++i) {
3657 		struct slgt_info *info = port_array[i];
3658 		tty_port_register_device(&info->port, serial_driver, info->line,
3659 				&info->pdev->dev);
3660 	}
3661 }
3662 
3663 static int init_one(struct pci_dev *dev,
3664 			      const struct pci_device_id *ent)
3665 {
3666 	if (pci_enable_device(dev)) {
3667 		printk("error enabling pci device %p\n", dev);
3668 		return -EIO;
3669 	}
3670 	pci_set_master(dev);
3671 	device_init(slgt_device_count, dev);
3672 	return 0;
3673 }
3674 
3675 static void remove_one(struct pci_dev *dev)
3676 {
3677 }
3678 
3679 static const struct tty_operations ops = {
3680 	.open = open,
3681 	.close = close,
3682 	.write = write,
3683 	.put_char = put_char,
3684 	.flush_chars = flush_chars,
3685 	.write_room = write_room,
3686 	.chars_in_buffer = chars_in_buffer,
3687 	.flush_buffer = flush_buffer,
3688 	.ioctl = ioctl,
3689 	.compat_ioctl = slgt_compat_ioctl,
3690 	.throttle = throttle,
3691 	.unthrottle = unthrottle,
3692 	.send_xchar = send_xchar,
3693 	.break_ctl = set_break,
3694 	.wait_until_sent = wait_until_sent,
3695 	.set_termios = set_termios,
3696 	.stop = tx_hold,
3697 	.start = tx_release,
3698 	.hangup = hangup,
3699 	.tiocmget = tiocmget,
3700 	.tiocmset = tiocmset,
3701 	.get_icount = get_icount,
3702 	.proc_show = synclink_gt_proc_show,
3703 };
3704 
3705 static void slgt_cleanup(void)
3706 {
3707 	int rc;
3708 	struct slgt_info *info;
3709 	struct slgt_info *tmp;
3710 
3711 	printk(KERN_INFO "unload %s\n", driver_name);
3712 
3713 	if (serial_driver) {
3714 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3715 			tty_unregister_device(serial_driver, info->line);
3716 		rc = tty_unregister_driver(serial_driver);
3717 		if (rc)
3718 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3719 		put_tty_driver(serial_driver);
3720 	}
3721 
3722 	/* reset devices */
3723 	info = slgt_device_list;
3724 	while(info) {
3725 		reset_port(info);
3726 		info = info->next_device;
3727 	}
3728 
3729 	/* release devices */
3730 	info = slgt_device_list;
3731 	while(info) {
3732 #if SYNCLINK_GENERIC_HDLC
3733 		hdlcdev_exit(info);
3734 #endif
3735 		free_dma_bufs(info);
3736 		free_tmp_rbuf(info);
3737 		if (info->port_num == 0)
3738 			release_resources(info);
3739 		tmp = info;
3740 		info = info->next_device;
3741 		tty_port_destroy(&tmp->port);
3742 		kfree(tmp);
3743 	}
3744 
3745 	if (pci_registered)
3746 		pci_unregister_driver(&pci_driver);
3747 }
3748 
3749 /*
3750  *  Driver initialization entry point.
3751  */
3752 static int __init slgt_init(void)
3753 {
3754 	int rc;
3755 
3756 	printk(KERN_INFO "%s\n", driver_name);
3757 
3758 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3759 	if (!serial_driver) {
3760 		printk("%s can't allocate tty driver\n", driver_name);
3761 		return -ENOMEM;
3762 	}
3763 
3764 	/* Initialize the tty_driver structure */
3765 
3766 	serial_driver->driver_name = slgt_driver_name;
3767 	serial_driver->name = tty_dev_prefix;
3768 	serial_driver->major = ttymajor;
3769 	serial_driver->minor_start = 64;
3770 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3771 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3772 	serial_driver->init_termios = tty_std_termios;
3773 	serial_driver->init_termios.c_cflag =
3774 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3775 	serial_driver->init_termios.c_ispeed = 9600;
3776 	serial_driver->init_termios.c_ospeed = 9600;
3777 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3778 	tty_set_operations(serial_driver, &ops);
3779 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3780 		DBGERR(("%s can't register serial driver\n", driver_name));
3781 		put_tty_driver(serial_driver);
3782 		serial_driver = NULL;
3783 		goto error;
3784 	}
3785 
3786 	printk(KERN_INFO "%s, tty major#%d\n",
3787 	       driver_name, serial_driver->major);
3788 
3789 	slgt_device_count = 0;
3790 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3791 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3792 		goto error;
3793 	}
3794 	pci_registered = true;
3795 
3796 	if (!slgt_device_list)
3797 		printk("%s no devices found\n",driver_name);
3798 
3799 	return 0;
3800 
3801 error:
3802 	slgt_cleanup();
3803 	return rc;
3804 }
3805 
3806 static void __exit slgt_exit(void)
3807 {
3808 	slgt_cleanup();
3809 }
3810 
3811 module_init(slgt_init);
3812 module_exit(slgt_exit);
3813 
3814 /*
3815  * register access routines
3816  */
3817 
3818 #define CALC_REGADDR() \
3819 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3820 	if (addr >= 0x80) \
3821 		reg_addr += (info->port_num) * 32; \
3822 	else if (addr >= 0x40)	\
3823 		reg_addr += (info->port_num) * 16;
3824 
3825 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3826 {
3827 	CALC_REGADDR();
3828 	return readb((void __iomem *)reg_addr);
3829 }
3830 
3831 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3832 {
3833 	CALC_REGADDR();
3834 	writeb(value, (void __iomem *)reg_addr);
3835 }
3836 
3837 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3838 {
3839 	CALC_REGADDR();
3840 	return readw((void __iomem *)reg_addr);
3841 }
3842 
3843 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3844 {
3845 	CALC_REGADDR();
3846 	writew(value, (void __iomem *)reg_addr);
3847 }
3848 
3849 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3850 {
3851 	CALC_REGADDR();
3852 	return readl((void __iomem *)reg_addr);
3853 }
3854 
3855 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3856 {
3857 	CALC_REGADDR();
3858 	writel(value, (void __iomem *)reg_addr);
3859 }
3860 
3861 static void rdma_reset(struct slgt_info *info)
3862 {
3863 	unsigned int i;
3864 
3865 	/* set reset bit */
3866 	wr_reg32(info, RDCSR, BIT1);
3867 
3868 	/* wait for enable bit cleared */
3869 	for(i=0 ; i < 1000 ; i++)
3870 		if (!(rd_reg32(info, RDCSR) & BIT0))
3871 			break;
3872 }
3873 
3874 static void tdma_reset(struct slgt_info *info)
3875 {
3876 	unsigned int i;
3877 
3878 	/* set reset bit */
3879 	wr_reg32(info, TDCSR, BIT1);
3880 
3881 	/* wait for enable bit cleared */
3882 	for(i=0 ; i < 1000 ; i++)
3883 		if (!(rd_reg32(info, TDCSR) & BIT0))
3884 			break;
3885 }
3886 
3887 /*
3888  * enable internal loopback
3889  * TxCLK and RxCLK are generated from BRG
3890  * and TxD is looped back to RxD internally.
3891  */
3892 static void enable_loopback(struct slgt_info *info)
3893 {
3894 	/* SCR (serial control) BIT2=loopback enable */
3895 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3896 
3897 	if (info->params.mode != MGSL_MODE_ASYNC) {
3898 		/* CCR (clock control)
3899 		 * 07..05  tx clock source (010 = BRG)
3900 		 * 04..02  rx clock source (010 = BRG)
3901 		 * 01      auxclk enable   (0 = disable)
3902 		 * 00      BRG enable      (1 = enable)
3903 		 *
3904 		 * 0100 1001
3905 		 */
3906 		wr_reg8(info, CCR, 0x49);
3907 
3908 		/* set speed if available, otherwise use default */
3909 		if (info->params.clock_speed)
3910 			set_rate(info, info->params.clock_speed);
3911 		else
3912 			set_rate(info, 3686400);
3913 	}
3914 }
3915 
3916 /*
3917  *  set baud rate generator to specified rate
3918  */
3919 static void set_rate(struct slgt_info *info, u32 rate)
3920 {
3921 	unsigned int div;
3922 	unsigned int osc = info->base_clock;
3923 
3924 	/* div = osc/rate - 1
3925 	 *
3926 	 * Round div up if osc/rate is not integer to
3927 	 * force to next slowest rate.
3928 	 */
3929 
3930 	if (rate) {
3931 		div = osc/rate;
3932 		if (!(osc % rate) && div)
3933 			div--;
3934 		wr_reg16(info, BDR, (unsigned short)div);
3935 	}
3936 }
3937 
3938 static void rx_stop(struct slgt_info *info)
3939 {
3940 	unsigned short val;
3941 
3942 	/* disable and reset receiver */
3943 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3944 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3945 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3946 
3947 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3948 
3949 	/* clear pending rx interrupts */
3950 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3951 
3952 	rdma_reset(info);
3953 
3954 	info->rx_enabled = false;
3955 	info->rx_restart = false;
3956 }
3957 
3958 static void rx_start(struct slgt_info *info)
3959 {
3960 	unsigned short val;
3961 
3962 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3963 
3964 	/* clear pending rx overrun IRQ */
3965 	wr_reg16(info, SSR, IRQ_RXOVER);
3966 
3967 	/* reset and disable receiver */
3968 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3969 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3970 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3971 
3972 	rdma_reset(info);
3973 	reset_rbufs(info);
3974 
3975 	if (info->rx_pio) {
3976 		/* rx request when rx FIFO not empty */
3977 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3978 		slgt_irq_on(info, IRQ_RXDATA);
3979 		if (info->params.mode == MGSL_MODE_ASYNC) {
3980 			/* enable saving of rx status */
3981 			wr_reg32(info, RDCSR, BIT6);
3982 		}
3983 	} else {
3984 		/* rx request when rx FIFO half full */
3985 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3986 		/* set 1st descriptor address */
3987 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3988 
3989 		if (info->params.mode != MGSL_MODE_ASYNC) {
3990 			/* enable rx DMA and DMA interrupt */
3991 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3992 		} else {
3993 			/* enable saving of rx status, rx DMA and DMA interrupt */
3994 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3995 		}
3996 	}
3997 
3998 	slgt_irq_on(info, IRQ_RXOVER);
3999 
4000 	/* enable receiver */
4001 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4002 
4003 	info->rx_restart = false;
4004 	info->rx_enabled = true;
4005 }
4006 
4007 static void tx_start(struct slgt_info *info)
4008 {
4009 	if (!info->tx_enabled) {
4010 		wr_reg16(info, TCR,
4011 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4012 		info->tx_enabled = true;
4013 	}
4014 
4015 	if (desc_count(info->tbufs[info->tbuf_start])) {
4016 		info->drop_rts_on_tx_done = false;
4017 
4018 		if (info->params.mode != MGSL_MODE_ASYNC) {
4019 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4020 				get_signals(info);
4021 				if (!(info->signals & SerialSignal_RTS)) {
4022 					info->signals |= SerialSignal_RTS;
4023 					set_signals(info);
4024 					info->drop_rts_on_tx_done = true;
4025 				}
4026 			}
4027 
4028 			slgt_irq_off(info, IRQ_TXDATA);
4029 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4030 			/* clear tx idle and underrun status bits */
4031 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4032 		} else {
4033 			slgt_irq_off(info, IRQ_TXDATA);
4034 			slgt_irq_on(info, IRQ_TXIDLE);
4035 			/* clear tx idle status bit */
4036 			wr_reg16(info, SSR, IRQ_TXIDLE);
4037 		}
4038 		/* set 1st descriptor address and start DMA */
4039 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4040 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4041 		info->tx_active = true;
4042 	}
4043 }
4044 
4045 static void tx_stop(struct slgt_info *info)
4046 {
4047 	unsigned short val;
4048 
4049 	del_timer(&info->tx_timer);
4050 
4051 	tdma_reset(info);
4052 
4053 	/* reset and disable transmitter */
4054 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4055 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4056 
4057 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4058 
4059 	/* clear tx idle and underrun status bit */
4060 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4061 
4062 	reset_tbufs(info);
4063 
4064 	info->tx_enabled = false;
4065 	info->tx_active = false;
4066 }
4067 
4068 static void reset_port(struct slgt_info *info)
4069 {
4070 	if (!info->reg_addr)
4071 		return;
4072 
4073 	tx_stop(info);
4074 	rx_stop(info);
4075 
4076 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4077 	set_signals(info);
4078 
4079 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4080 }
4081 
4082 static void reset_adapter(struct slgt_info *info)
4083 {
4084 	int i;
4085 	for (i=0; i < info->port_count; ++i) {
4086 		if (info->port_array[i])
4087 			reset_port(info->port_array[i]);
4088 	}
4089 }
4090 
4091 static void async_mode(struct slgt_info *info)
4092 {
4093   	unsigned short val;
4094 
4095 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4096 	tx_stop(info);
4097 	rx_stop(info);
4098 
4099 	/* TCR (tx control)
4100 	 *
4101 	 * 15..13  mode, 010=async
4102 	 * 12..10  encoding, 000=NRZ
4103 	 * 09      parity enable
4104 	 * 08      1=odd parity, 0=even parity
4105 	 * 07      1=RTS driver control
4106 	 * 06      1=break enable
4107 	 * 05..04  character length
4108 	 *         00=5 bits
4109 	 *         01=6 bits
4110 	 *         10=7 bits
4111 	 *         11=8 bits
4112 	 * 03      0=1 stop bit, 1=2 stop bits
4113 	 * 02      reset
4114 	 * 01      enable
4115 	 * 00      auto-CTS enable
4116 	 */
4117 	val = 0x4000;
4118 
4119 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4120 		val |= BIT7;
4121 
4122 	if (info->params.parity != ASYNC_PARITY_NONE) {
4123 		val |= BIT9;
4124 		if (info->params.parity == ASYNC_PARITY_ODD)
4125 			val |= BIT8;
4126 	}
4127 
4128 	switch (info->params.data_bits)
4129 	{
4130 	case 6: val |= BIT4; break;
4131 	case 7: val |= BIT5; break;
4132 	case 8: val |= BIT5 + BIT4; break;
4133 	}
4134 
4135 	if (info->params.stop_bits != 1)
4136 		val |= BIT3;
4137 
4138 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4139 		val |= BIT0;
4140 
4141 	wr_reg16(info, TCR, val);
4142 
4143 	/* RCR (rx control)
4144 	 *
4145 	 * 15..13  mode, 010=async
4146 	 * 12..10  encoding, 000=NRZ
4147 	 * 09      parity enable
4148 	 * 08      1=odd parity, 0=even parity
4149 	 * 07..06  reserved, must be 0
4150 	 * 05..04  character length
4151 	 *         00=5 bits
4152 	 *         01=6 bits
4153 	 *         10=7 bits
4154 	 *         11=8 bits
4155 	 * 03      reserved, must be zero
4156 	 * 02      reset
4157 	 * 01      enable
4158 	 * 00      auto-DCD enable
4159 	 */
4160 	val = 0x4000;
4161 
4162 	if (info->params.parity != ASYNC_PARITY_NONE) {
4163 		val |= BIT9;
4164 		if (info->params.parity == ASYNC_PARITY_ODD)
4165 			val |= BIT8;
4166 	}
4167 
4168 	switch (info->params.data_bits)
4169 	{
4170 	case 6: val |= BIT4; break;
4171 	case 7: val |= BIT5; break;
4172 	case 8: val |= BIT5 + BIT4; break;
4173 	}
4174 
4175 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4176 		val |= BIT0;
4177 
4178 	wr_reg16(info, RCR, val);
4179 
4180 	/* CCR (clock control)
4181 	 *
4182 	 * 07..05  011 = tx clock source is BRG/16
4183 	 * 04..02  010 = rx clock source is BRG
4184 	 * 01      0 = auxclk disabled
4185 	 * 00      1 = BRG enabled
4186 	 *
4187 	 * 0110 1001
4188 	 */
4189 	wr_reg8(info, CCR, 0x69);
4190 
4191 	msc_set_vcr(info);
4192 
4193 	/* SCR (serial control)
4194 	 *
4195 	 * 15  1=tx req on FIFO half empty
4196 	 * 14  1=rx req on FIFO half full
4197 	 * 13  tx data  IRQ enable
4198 	 * 12  tx idle  IRQ enable
4199 	 * 11  rx break on IRQ enable
4200 	 * 10  rx data  IRQ enable
4201 	 * 09  rx break off IRQ enable
4202 	 * 08  overrun  IRQ enable
4203 	 * 07  DSR      IRQ enable
4204 	 * 06  CTS      IRQ enable
4205 	 * 05  DCD      IRQ enable
4206 	 * 04  RI       IRQ enable
4207 	 * 03  0=16x sampling, 1=8x sampling
4208 	 * 02  1=txd->rxd internal loopback enable
4209 	 * 01  reserved, must be zero
4210 	 * 00  1=master IRQ enable
4211 	 */
4212 	val = BIT15 + BIT14 + BIT0;
4213 	/* JCR[8] : 1 = x8 async mode feature available */
4214 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4215 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4216 	     (info->base_clock % (info->params.data_rate * 16)))) {
4217 		/* use 8x sampling */
4218 		val |= BIT3;
4219 		set_rate(info, info->params.data_rate * 8);
4220 	} else {
4221 		/* use 16x sampling */
4222 		set_rate(info, info->params.data_rate * 16);
4223 	}
4224 	wr_reg16(info, SCR, val);
4225 
4226 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4227 
4228 	if (info->params.loopback)
4229 		enable_loopback(info);
4230 }
4231 
4232 static void sync_mode(struct slgt_info *info)
4233 {
4234 	unsigned short val;
4235 
4236 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4237 	tx_stop(info);
4238 	rx_stop(info);
4239 
4240 	/* TCR (tx control)
4241 	 *
4242 	 * 15..13  mode
4243 	 *         000=HDLC/SDLC
4244 	 *         001=raw bit synchronous
4245 	 *         010=asynchronous/isochronous
4246 	 *         011=monosync byte synchronous
4247 	 *         100=bisync byte synchronous
4248 	 *         101=xsync byte synchronous
4249 	 * 12..10  encoding
4250 	 * 09      CRC enable
4251 	 * 08      CRC32
4252 	 * 07      1=RTS driver control
4253 	 * 06      preamble enable
4254 	 * 05..04  preamble length
4255 	 * 03      share open/close flag
4256 	 * 02      reset
4257 	 * 01      enable
4258 	 * 00      auto-CTS enable
4259 	 */
4260 	val = BIT2;
4261 
4262 	switch(info->params.mode) {
4263 	case MGSL_MODE_XSYNC:
4264 		val |= BIT15 + BIT13;
4265 		break;
4266 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4267 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4268 	case MGSL_MODE_RAW:      val |= BIT13; break;
4269 	}
4270 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4271 		val |= BIT7;
4272 
4273 	switch(info->params.encoding)
4274 	{
4275 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4276 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4277 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4278 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4279 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4280 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4281 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4282 	}
4283 
4284 	switch (info->params.crc_type & HDLC_CRC_MASK)
4285 	{
4286 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4287 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4288 	}
4289 
4290 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4291 		val |= BIT6;
4292 
4293 	switch (info->params.preamble_length)
4294 	{
4295 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4296 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4297 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4298 	}
4299 
4300 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4301 		val |= BIT0;
4302 
4303 	wr_reg16(info, TCR, val);
4304 
4305 	/* TPR (transmit preamble) */
4306 
4307 	switch (info->params.preamble)
4308 	{
4309 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4310 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4311 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4312 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4313 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4314 	default:                          val = 0x7e; break;
4315 	}
4316 	wr_reg8(info, TPR, (unsigned char)val);
4317 
4318 	/* RCR (rx control)
4319 	 *
4320 	 * 15..13  mode
4321 	 *         000=HDLC/SDLC
4322 	 *         001=raw bit synchronous
4323 	 *         010=asynchronous/isochronous
4324 	 *         011=monosync byte synchronous
4325 	 *         100=bisync byte synchronous
4326 	 *         101=xsync byte synchronous
4327 	 * 12..10  encoding
4328 	 * 09      CRC enable
4329 	 * 08      CRC32
4330 	 * 07..03  reserved, must be 0
4331 	 * 02      reset
4332 	 * 01      enable
4333 	 * 00      auto-DCD enable
4334 	 */
4335 	val = 0;
4336 
4337 	switch(info->params.mode) {
4338 	case MGSL_MODE_XSYNC:
4339 		val |= BIT15 + BIT13;
4340 		break;
4341 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4342 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4343 	case MGSL_MODE_RAW:      val |= BIT13; break;
4344 	}
4345 
4346 	switch(info->params.encoding)
4347 	{
4348 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4349 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4350 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4351 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4352 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4353 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4354 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4355 	}
4356 
4357 	switch (info->params.crc_type & HDLC_CRC_MASK)
4358 	{
4359 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4360 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4361 	}
4362 
4363 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4364 		val |= BIT0;
4365 
4366 	wr_reg16(info, RCR, val);
4367 
4368 	/* CCR (clock control)
4369 	 *
4370 	 * 07..05  tx clock source
4371 	 * 04..02  rx clock source
4372 	 * 01      auxclk enable
4373 	 * 00      BRG enable
4374 	 */
4375 	val = 0;
4376 
4377 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4378 	{
4379 		// when RxC source is DPLL, BRG generates 16X DPLL
4380 		// reference clock, so take TxC from BRG/16 to get
4381 		// transmit clock at actual data rate
4382 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4383 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4384 		else
4385 			val |= BIT6;	/* 010, txclk = BRG */
4386 	}
4387 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4388 		val |= BIT7;	/* 100, txclk = DPLL Input */
4389 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4390 		val |= BIT5;	/* 001, txclk = RXC Input */
4391 
4392 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4393 		val |= BIT3;	/* 010, rxclk = BRG */
4394 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4395 		val |= BIT4;	/* 100, rxclk = DPLL */
4396 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4397 		val |= BIT2;	/* 001, rxclk = TXC Input */
4398 
4399 	if (info->params.clock_speed)
4400 		val |= BIT1 + BIT0;
4401 
4402 	wr_reg8(info, CCR, (unsigned char)val);
4403 
4404 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4405 	{
4406 		// program DPLL mode
4407 		switch(info->params.encoding)
4408 		{
4409 		case HDLC_ENCODING_BIPHASE_MARK:
4410 		case HDLC_ENCODING_BIPHASE_SPACE:
4411 			val = BIT7; break;
4412 		case HDLC_ENCODING_BIPHASE_LEVEL:
4413 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4414 			val = BIT7 + BIT6; break;
4415 		default: val = BIT6;	// NRZ encodings
4416 		}
4417 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4418 
4419 		// DPLL requires a 16X reference clock from BRG
4420 		set_rate(info, info->params.clock_speed * 16);
4421 	}
4422 	else
4423 		set_rate(info, info->params.clock_speed);
4424 
4425 	tx_set_idle(info);
4426 
4427 	msc_set_vcr(info);
4428 
4429 	/* SCR (serial control)
4430 	 *
4431 	 * 15  1=tx req on FIFO half empty
4432 	 * 14  1=rx req on FIFO half full
4433 	 * 13  tx data  IRQ enable
4434 	 * 12  tx idle  IRQ enable
4435 	 * 11  underrun IRQ enable
4436 	 * 10  rx data  IRQ enable
4437 	 * 09  rx idle  IRQ enable
4438 	 * 08  overrun  IRQ enable
4439 	 * 07  DSR      IRQ enable
4440 	 * 06  CTS      IRQ enable
4441 	 * 05  DCD      IRQ enable
4442 	 * 04  RI       IRQ enable
4443 	 * 03  reserved, must be zero
4444 	 * 02  1=txd->rxd internal loopback enable
4445 	 * 01  reserved, must be zero
4446 	 * 00  1=master IRQ enable
4447 	 */
4448 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4449 
4450 	if (info->params.loopback)
4451 		enable_loopback(info);
4452 }
4453 
4454 /*
4455  *  set transmit idle mode
4456  */
4457 static void tx_set_idle(struct slgt_info *info)
4458 {
4459 	unsigned char val;
4460 	unsigned short tcr;
4461 
4462 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4463 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4464 	 */
4465 	tcr = rd_reg16(info, TCR);
4466 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4467 		/* disable preamble, set idle size to 16 bits */
4468 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4469 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4470 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4471 	} else if (!(tcr & BIT6)) {
4472 		/* preamble is disabled, set idle size to 8 bits */
4473 		tcr &= ~(BIT5 + BIT4);
4474 	}
4475 	wr_reg16(info, TCR, tcr);
4476 
4477 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4478 		/* LSB of custom tx idle specified in tx idle register */
4479 		val = (unsigned char)(info->idle_mode & 0xff);
4480 	} else {
4481 		/* standard 8 bit idle patterns */
4482 		switch(info->idle_mode)
4483 		{
4484 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4485 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4486 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4487 		case HDLC_TXIDLE_ZEROS:
4488 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4489 		default:                         val = 0xff;
4490 		}
4491 	}
4492 
4493 	wr_reg8(info, TIR, val);
4494 }
4495 
4496 /*
4497  * get state of V24 status (input) signals
4498  */
4499 static void get_signals(struct slgt_info *info)
4500 {
4501 	unsigned short status = rd_reg16(info, SSR);
4502 
4503 	/* clear all serial signals except RTS and DTR */
4504 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4505 
4506 	if (status & BIT3)
4507 		info->signals |= SerialSignal_DSR;
4508 	if (status & BIT2)
4509 		info->signals |= SerialSignal_CTS;
4510 	if (status & BIT1)
4511 		info->signals |= SerialSignal_DCD;
4512 	if (status & BIT0)
4513 		info->signals |= SerialSignal_RI;
4514 }
4515 
4516 /*
4517  * set V.24 Control Register based on current configuration
4518  */
4519 static void msc_set_vcr(struct slgt_info *info)
4520 {
4521 	unsigned char val = 0;
4522 
4523 	/* VCR (V.24 control)
4524 	 *
4525 	 * 07..04  serial IF select
4526 	 * 03      DTR
4527 	 * 02      RTS
4528 	 * 01      LL
4529 	 * 00      RL
4530 	 */
4531 
4532 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4533 	{
4534 	case MGSL_INTERFACE_RS232:
4535 		val |= BIT5; /* 0010 */
4536 		break;
4537 	case MGSL_INTERFACE_V35:
4538 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4539 		break;
4540 	case MGSL_INTERFACE_RS422:
4541 		val |= BIT6; /* 0100 */
4542 		break;
4543 	}
4544 
4545 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4546 		val |= BIT4;
4547 	if (info->signals & SerialSignal_DTR)
4548 		val |= BIT3;
4549 	if (info->signals & SerialSignal_RTS)
4550 		val |= BIT2;
4551 	if (info->if_mode & MGSL_INTERFACE_LL)
4552 		val |= BIT1;
4553 	if (info->if_mode & MGSL_INTERFACE_RL)
4554 		val |= BIT0;
4555 	wr_reg8(info, VCR, val);
4556 }
4557 
4558 /*
4559  * set state of V24 control (output) signals
4560  */
4561 static void set_signals(struct slgt_info *info)
4562 {
4563 	unsigned char val = rd_reg8(info, VCR);
4564 	if (info->signals & SerialSignal_DTR)
4565 		val |= BIT3;
4566 	else
4567 		val &= ~BIT3;
4568 	if (info->signals & SerialSignal_RTS)
4569 		val |= BIT2;
4570 	else
4571 		val &= ~BIT2;
4572 	wr_reg8(info, VCR, val);
4573 }
4574 
4575 /*
4576  * free range of receive DMA buffers (i to last)
4577  */
4578 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4579 {
4580 	int done = 0;
4581 
4582 	while(!done) {
4583 		/* reset current buffer for reuse */
4584 		info->rbufs[i].status = 0;
4585 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4586 		if (i == last)
4587 			done = 1;
4588 		if (++i == info->rbuf_count)
4589 			i = 0;
4590 	}
4591 	info->rbuf_current = i;
4592 }
4593 
4594 /*
4595  * mark all receive DMA buffers as free
4596  */
4597 static void reset_rbufs(struct slgt_info *info)
4598 {
4599 	free_rbufs(info, 0, info->rbuf_count - 1);
4600 	info->rbuf_fill_index = 0;
4601 	info->rbuf_fill_count = 0;
4602 }
4603 
4604 /*
4605  * pass receive HDLC frame to upper layer
4606  *
4607  * return true if frame available, otherwise false
4608  */
4609 static bool rx_get_frame(struct slgt_info *info)
4610 {
4611 	unsigned int start, end;
4612 	unsigned short status;
4613 	unsigned int framesize = 0;
4614 	unsigned long flags;
4615 	struct tty_struct *tty = info->port.tty;
4616 	unsigned char addr_field = 0xff;
4617 	unsigned int crc_size = 0;
4618 
4619 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4620 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4621 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4622 	}
4623 
4624 check_again:
4625 
4626 	framesize = 0;
4627 	addr_field = 0xff;
4628 	start = end = info->rbuf_current;
4629 
4630 	for (;;) {
4631 		if (!desc_complete(info->rbufs[end]))
4632 			goto cleanup;
4633 
4634 		if (framesize == 0 && info->params.addr_filter != 0xff)
4635 			addr_field = info->rbufs[end].buf[0];
4636 
4637 		framesize += desc_count(info->rbufs[end]);
4638 
4639 		if (desc_eof(info->rbufs[end]))
4640 			break;
4641 
4642 		if (++end == info->rbuf_count)
4643 			end = 0;
4644 
4645 		if (end == info->rbuf_current) {
4646 			if (info->rx_enabled){
4647 				spin_lock_irqsave(&info->lock,flags);
4648 				rx_start(info);
4649 				spin_unlock_irqrestore(&info->lock,flags);
4650 			}
4651 			goto cleanup;
4652 		}
4653 	}
4654 
4655 	/* status
4656 	 *
4657 	 * 15      buffer complete
4658 	 * 14..06  reserved
4659 	 * 05..04  residue
4660 	 * 02      eof (end of frame)
4661 	 * 01      CRC error
4662 	 * 00      abort
4663 	 */
4664 	status = desc_status(info->rbufs[end]);
4665 
4666 	/* ignore CRC bit if not using CRC (bit is undefined) */
4667 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4668 		status &= ~BIT1;
4669 
4670 	if (framesize == 0 ||
4671 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4672 		free_rbufs(info, start, end);
4673 		goto check_again;
4674 	}
4675 
4676 	if (framesize < (2 + crc_size) || status & BIT0) {
4677 		info->icount.rxshort++;
4678 		framesize = 0;
4679 	} else if (status & BIT1) {
4680 		info->icount.rxcrc++;
4681 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4682 			framesize = 0;
4683 	}
4684 
4685 #if SYNCLINK_GENERIC_HDLC
4686 	if (framesize == 0) {
4687 		info->netdev->stats.rx_errors++;
4688 		info->netdev->stats.rx_frame_errors++;
4689 	}
4690 #endif
4691 
4692 	DBGBH(("%s rx frame status=%04X size=%d\n",
4693 		info->device_name, status, framesize));
4694 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4695 
4696 	if (framesize) {
4697 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4698 			framesize -= crc_size;
4699 			crc_size = 0;
4700 		}
4701 
4702 		if (framesize > info->max_frame_size + crc_size)
4703 			info->icount.rxlong++;
4704 		else {
4705 			/* copy dma buffer(s) to contiguous temp buffer */
4706 			int copy_count = framesize;
4707 			int i = start;
4708 			unsigned char *p = info->tmp_rbuf;
4709 			info->tmp_rbuf_count = framesize;
4710 
4711 			info->icount.rxok++;
4712 
4713 			while(copy_count) {
4714 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4715 				memcpy(p, info->rbufs[i].buf, partial_count);
4716 				p += partial_count;
4717 				copy_count -= partial_count;
4718 				if (++i == info->rbuf_count)
4719 					i = 0;
4720 			}
4721 
4722 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4723 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4724 				framesize++;
4725 			}
4726 
4727 #if SYNCLINK_GENERIC_HDLC
4728 			if (info->netcount)
4729 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4730 			else
4731 #endif
4732 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4733 		}
4734 	}
4735 	free_rbufs(info, start, end);
4736 	return true;
4737 
4738 cleanup:
4739 	return false;
4740 }
4741 
4742 /*
4743  * pass receive buffer (RAW synchronous mode) to tty layer
4744  * return true if buffer available, otherwise false
4745  */
4746 static bool rx_get_buf(struct slgt_info *info)
4747 {
4748 	unsigned int i = info->rbuf_current;
4749 	unsigned int count;
4750 
4751 	if (!desc_complete(info->rbufs[i]))
4752 		return false;
4753 	count = desc_count(info->rbufs[i]);
4754 	switch(info->params.mode) {
4755 	case MGSL_MODE_MONOSYNC:
4756 	case MGSL_MODE_BISYNC:
4757 	case MGSL_MODE_XSYNC:
4758 		/* ignore residue in byte synchronous modes */
4759 		if (desc_residue(info->rbufs[i]))
4760 			count--;
4761 		break;
4762 	}
4763 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4764 	DBGINFO(("rx_get_buf size=%d\n", count));
4765 	if (count)
4766 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4767 				  info->flag_buf, count);
4768 	free_rbufs(info, i, i);
4769 	return true;
4770 }
4771 
4772 static void reset_tbufs(struct slgt_info *info)
4773 {
4774 	unsigned int i;
4775 	info->tbuf_current = 0;
4776 	for (i=0 ; i < info->tbuf_count ; i++) {
4777 		info->tbufs[i].status = 0;
4778 		info->tbufs[i].count  = 0;
4779 	}
4780 }
4781 
4782 /*
4783  * return number of free transmit DMA buffers
4784  */
4785 static unsigned int free_tbuf_count(struct slgt_info *info)
4786 {
4787 	unsigned int count = 0;
4788 	unsigned int i = info->tbuf_current;
4789 
4790 	do
4791 	{
4792 		if (desc_count(info->tbufs[i]))
4793 			break; /* buffer in use */
4794 		++count;
4795 		if (++i == info->tbuf_count)
4796 			i=0;
4797 	} while (i != info->tbuf_current);
4798 
4799 	/* if tx DMA active, last zero count buffer is in use */
4800 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4801 		--count;
4802 
4803 	return count;
4804 }
4805 
4806 /*
4807  * return number of bytes in unsent transmit DMA buffers
4808  * and the serial controller tx FIFO
4809  */
4810 static unsigned int tbuf_bytes(struct slgt_info *info)
4811 {
4812 	unsigned int total_count = 0;
4813 	unsigned int i = info->tbuf_current;
4814 	unsigned int reg_value;
4815 	unsigned int count;
4816 	unsigned int active_buf_count = 0;
4817 
4818 	/*
4819 	 * Add descriptor counts for all tx DMA buffers.
4820 	 * If count is zero (cleared by DMA controller after read),
4821 	 * the buffer is complete or is actively being read from.
4822 	 *
4823 	 * Record buf_count of last buffer with zero count starting
4824 	 * from current ring position. buf_count is mirror
4825 	 * copy of count and is not cleared by serial controller.
4826 	 * If DMA controller is active, that buffer is actively
4827 	 * being read so add to total.
4828 	 */
4829 	do {
4830 		count = desc_count(info->tbufs[i]);
4831 		if (count)
4832 			total_count += count;
4833 		else if (!total_count)
4834 			active_buf_count = info->tbufs[i].buf_count;
4835 		if (++i == info->tbuf_count)
4836 			i = 0;
4837 	} while (i != info->tbuf_current);
4838 
4839 	/* read tx DMA status register */
4840 	reg_value = rd_reg32(info, TDCSR);
4841 
4842 	/* if tx DMA active, last zero count buffer is in use */
4843 	if (reg_value & BIT0)
4844 		total_count += active_buf_count;
4845 
4846 	/* add tx FIFO count = reg_value[15..8] */
4847 	total_count += (reg_value >> 8) & 0xff;
4848 
4849 	/* if transmitter active add one byte for shift register */
4850 	if (info->tx_active)
4851 		total_count++;
4852 
4853 	return total_count;
4854 }
4855 
4856 /*
4857  * load data into transmit DMA buffer ring and start transmitter if needed
4858  * return true if data accepted, otherwise false (buffers full)
4859  */
4860 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4861 {
4862 	unsigned short count;
4863 	unsigned int i;
4864 	struct slgt_desc *d;
4865 
4866 	/* check required buffer space */
4867 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4868 		return false;
4869 
4870 	DBGDATA(info, buf, size, "tx");
4871 
4872 	/*
4873 	 * copy data to one or more DMA buffers in circular ring
4874 	 * tbuf_start   = first buffer for this data
4875 	 * tbuf_current = next free buffer
4876 	 *
4877 	 * Copy all data before making data visible to DMA controller by
4878 	 * setting descriptor count of the first buffer.
4879 	 * This prevents an active DMA controller from reading the first DMA
4880 	 * buffers of a frame and stopping before the final buffers are filled.
4881 	 */
4882 
4883 	info->tbuf_start = i = info->tbuf_current;
4884 
4885 	while (size) {
4886 		d = &info->tbufs[i];
4887 
4888 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4889 		memcpy(d->buf, buf, count);
4890 
4891 		size -= count;
4892 		buf  += count;
4893 
4894 		/*
4895 		 * set EOF bit for last buffer of HDLC frame or
4896 		 * for every buffer in raw mode
4897 		 */
4898 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4899 		    info->params.mode == MGSL_MODE_RAW)
4900 			set_desc_eof(*d, 1);
4901 		else
4902 			set_desc_eof(*d, 0);
4903 
4904 		/* set descriptor count for all but first buffer */
4905 		if (i != info->tbuf_start)
4906 			set_desc_count(*d, count);
4907 		d->buf_count = count;
4908 
4909 		if (++i == info->tbuf_count)
4910 			i = 0;
4911 	}
4912 
4913 	info->tbuf_current = i;
4914 
4915 	/* set first buffer count to make new data visible to DMA controller */
4916 	d = &info->tbufs[info->tbuf_start];
4917 	set_desc_count(*d, d->buf_count);
4918 
4919 	/* start transmitter if needed and update transmit timeout */
4920 	if (!info->tx_active)
4921 		tx_start(info);
4922 	update_tx_timer(info);
4923 
4924 	return true;
4925 }
4926 
4927 static int register_test(struct slgt_info *info)
4928 {
4929 	static unsigned short patterns[] =
4930 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4931 	static unsigned int count = ARRAY_SIZE(patterns);
4932 	unsigned int i;
4933 	int rc = 0;
4934 
4935 	for (i=0 ; i < count ; i++) {
4936 		wr_reg16(info, TIR, patterns[i]);
4937 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4938 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4939 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4940 			rc = -ENODEV;
4941 			break;
4942 		}
4943 	}
4944 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4945 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4946 	return rc;
4947 }
4948 
4949 static int irq_test(struct slgt_info *info)
4950 {
4951 	unsigned long timeout;
4952 	unsigned long flags;
4953 	struct tty_struct *oldtty = info->port.tty;
4954 	u32 speed = info->params.data_rate;
4955 
4956 	info->params.data_rate = 921600;
4957 	info->port.tty = NULL;
4958 
4959 	spin_lock_irqsave(&info->lock, flags);
4960 	async_mode(info);
4961 	slgt_irq_on(info, IRQ_TXIDLE);
4962 
4963 	/* enable transmitter */
4964 	wr_reg16(info, TCR,
4965 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4966 
4967 	/* write one byte and wait for tx idle */
4968 	wr_reg16(info, TDR, 0);
4969 
4970 	/* assume failure */
4971 	info->init_error = DiagStatus_IrqFailure;
4972 	info->irq_occurred = false;
4973 
4974 	spin_unlock_irqrestore(&info->lock, flags);
4975 
4976 	timeout=100;
4977 	while(timeout-- && !info->irq_occurred)
4978 		msleep_interruptible(10);
4979 
4980 	spin_lock_irqsave(&info->lock,flags);
4981 	reset_port(info);
4982 	spin_unlock_irqrestore(&info->lock,flags);
4983 
4984 	info->params.data_rate = speed;
4985 	info->port.tty = oldtty;
4986 
4987 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4988 	return info->irq_occurred ? 0 : -ENODEV;
4989 }
4990 
4991 static int loopback_test_rx(struct slgt_info *info)
4992 {
4993 	unsigned char *src, *dest;
4994 	int count;
4995 
4996 	if (desc_complete(info->rbufs[0])) {
4997 		count = desc_count(info->rbufs[0]);
4998 		src   = info->rbufs[0].buf;
4999 		dest  = info->tmp_rbuf;
5000 
5001 		for( ; count ; count-=2, src+=2) {
5002 			/* src=data byte (src+1)=status byte */
5003 			if (!(*(src+1) & (BIT9 + BIT8))) {
5004 				*dest = *src;
5005 				dest++;
5006 				info->tmp_rbuf_count++;
5007 			}
5008 		}
5009 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5010 		return 1;
5011 	}
5012 	return 0;
5013 }
5014 
5015 static int loopback_test(struct slgt_info *info)
5016 {
5017 #define TESTFRAMESIZE 20
5018 
5019 	unsigned long timeout;
5020 	u16 count = TESTFRAMESIZE;
5021 	unsigned char buf[TESTFRAMESIZE];
5022 	int rc = -ENODEV;
5023 	unsigned long flags;
5024 
5025 	struct tty_struct *oldtty = info->port.tty;
5026 	MGSL_PARAMS params;
5027 
5028 	memcpy(&params, &info->params, sizeof(params));
5029 
5030 	info->params.mode = MGSL_MODE_ASYNC;
5031 	info->params.data_rate = 921600;
5032 	info->params.loopback = 1;
5033 	info->port.tty = NULL;
5034 
5035 	/* build and send transmit frame */
5036 	for (count = 0; count < TESTFRAMESIZE; ++count)
5037 		buf[count] = (unsigned char)count;
5038 
5039 	info->tmp_rbuf_count = 0;
5040 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5041 
5042 	/* program hardware for HDLC and enabled receiver */
5043 	spin_lock_irqsave(&info->lock,flags);
5044 	async_mode(info);
5045 	rx_start(info);
5046 	tx_load(info, buf, count);
5047 	spin_unlock_irqrestore(&info->lock, flags);
5048 
5049 	/* wait for receive complete */
5050 	for (timeout = 100; timeout; --timeout) {
5051 		msleep_interruptible(10);
5052 		if (loopback_test_rx(info)) {
5053 			rc = 0;
5054 			break;
5055 		}
5056 	}
5057 
5058 	/* verify received frame length and contents */
5059 	if (!rc && (info->tmp_rbuf_count != count ||
5060 		  memcmp(buf, info->tmp_rbuf, count))) {
5061 		rc = -ENODEV;
5062 	}
5063 
5064 	spin_lock_irqsave(&info->lock,flags);
5065 	reset_adapter(info);
5066 	spin_unlock_irqrestore(&info->lock,flags);
5067 
5068 	memcpy(&info->params, &params, sizeof(info->params));
5069 	info->port.tty = oldtty;
5070 
5071 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5072 	return rc;
5073 }
5074 
5075 static int adapter_test(struct slgt_info *info)
5076 {
5077 	DBGINFO(("testing %s\n", info->device_name));
5078 	if (register_test(info) < 0) {
5079 		printk("register test failure %s addr=%08X\n",
5080 			info->device_name, info->phys_reg_addr);
5081 	} else if (irq_test(info) < 0) {
5082 		printk("IRQ test failure %s IRQ=%d\n",
5083 			info->device_name, info->irq_level);
5084 	} else if (loopback_test(info) < 0) {
5085 		printk("loopback test failure %s\n", info->device_name);
5086 	}
5087 	return info->init_error;
5088 }
5089 
5090 /*
5091  * transmit timeout handler
5092  */
5093 static void tx_timeout(struct timer_list *t)
5094 {
5095 	struct slgt_info *info = from_timer(info, t, tx_timer);
5096 	unsigned long flags;
5097 
5098 	DBGINFO(("%s tx_timeout\n", info->device_name));
5099 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5100 		info->icount.txtimeout++;
5101 	}
5102 	spin_lock_irqsave(&info->lock,flags);
5103 	tx_stop(info);
5104 	spin_unlock_irqrestore(&info->lock,flags);
5105 
5106 #if SYNCLINK_GENERIC_HDLC
5107 	if (info->netcount)
5108 		hdlcdev_tx_done(info);
5109 	else
5110 #endif
5111 		bh_transmit(info);
5112 }
5113 
5114 /*
5115  * receive buffer polling timer
5116  */
5117 static void rx_timeout(struct timer_list *t)
5118 {
5119 	struct slgt_info *info = from_timer(info, t, rx_timer);
5120 	unsigned long flags;
5121 
5122 	DBGINFO(("%s rx_timeout\n", info->device_name));
5123 	spin_lock_irqsave(&info->lock, flags);
5124 	info->pending_bh |= BH_RECEIVE;
5125 	spin_unlock_irqrestore(&info->lock, flags);
5126 	bh_handler(&info->task);
5127 }
5128 
5129