xref: /linux/drivers/tty/synclink_gt.c (revision 662fa3d6099374c4615bf64d06895e3573b935b2)
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 void wait_until_sent(struct tty_struct *tty, int timeout);
141 static void flush_buffer(struct tty_struct *tty);
142 static void tx_release(struct tty_struct *tty);
143 
144 /*
145  * generic HDLC support
146  */
147 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
148 
149 
150 /*
151  * device specific structures, macros and functions
152  */
153 
154 #define SLGT_MAX_PORTS 4
155 #define SLGT_REG_SIZE  256
156 
157 /*
158  * conditional wait facility
159  */
160 struct cond_wait {
161 	struct cond_wait *next;
162 	wait_queue_head_t q;
163 	wait_queue_entry_t wait;
164 	unsigned int data;
165 };
166 static void flush_cond_wait(struct cond_wait **head);
167 
168 /*
169  * DMA buffer descriptor and access macros
170  */
171 struct slgt_desc
172 {
173 	__le16 count;
174 	__le16 status;
175 	__le32 pbuf;  /* physical address of data buffer */
176 	__le32 next;  /* physical address of next descriptor */
177 
178 	/* driver book keeping */
179 	char *buf;          /* virtual  address of data buffer */
180     	unsigned int pdesc; /* physical address of this descriptor */
181 	dma_addr_t buf_dma_addr;
182 	unsigned short buf_count;
183 };
184 
185 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
186 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
187 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
188 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
189 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
190 #define desc_count(a)      (le16_to_cpu((a).count))
191 #define desc_status(a)     (le16_to_cpu((a).status))
192 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
193 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
194 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
195 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
196 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
197 
198 struct _input_signal_events {
199 	int ri_up;
200 	int ri_down;
201 	int dsr_up;
202 	int dsr_down;
203 	int dcd_up;
204 	int dcd_down;
205 	int cts_up;
206 	int cts_down;
207 };
208 
209 /*
210  * device instance data structure
211  */
212 struct slgt_info {
213 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
214 	struct tty_port port;
215 
216 	struct slgt_info *next_device;	/* device list link */
217 
218 	int magic;
219 
220 	char device_name[25];
221 	struct pci_dev *pdev;
222 
223 	int port_count;  /* count of ports on adapter */
224 	int adapter_num; /* adapter instance number */
225 	int port_num;    /* port instance number */
226 
227 	/* array of pointers to port contexts on this adapter */
228 	struct slgt_info *port_array[SLGT_MAX_PORTS];
229 
230 	int			line;		/* tty line instance number */
231 
232 	struct mgsl_icount	icount;
233 
234 	int			timeout;
235 	int			x_char;		/* xon/xoff character */
236 	unsigned int		read_status_mask;
237 	unsigned int 		ignore_status_mask;
238 
239 	wait_queue_head_t	status_event_wait_q;
240 	wait_queue_head_t	event_wait_q;
241 	struct timer_list	tx_timer;
242 	struct timer_list	rx_timer;
243 
244 	unsigned int            gpio_present;
245 	struct cond_wait        *gpio_wait_q;
246 
247 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
248 
249 	struct work_struct task;
250 	u32 pending_bh;
251 	bool bh_requested;
252 	bool bh_running;
253 
254 	int isr_overflow;
255 	bool irq_requested;	/* true if IRQ requested */
256 	bool irq_occurred;	/* for diagnostics use */
257 
258 	/* device configuration */
259 
260 	unsigned int bus_type;
261 	unsigned int irq_level;
262 	unsigned long irq_flags;
263 
264 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
265 	u32 phys_reg_addr;
266 	bool reg_addr_requested;
267 
268 	MGSL_PARAMS params;       /* communications parameters */
269 	u32 idle_mode;
270 	u32 max_frame_size;       /* as set by device config */
271 
272 	unsigned int rbuf_fill_level;
273 	unsigned int rx_pio;
274 	unsigned int if_mode;
275 	unsigned int base_clock;
276 	unsigned int xsync;
277 	unsigned int xctrl;
278 
279 	/* device status */
280 
281 	bool rx_enabled;
282 	bool rx_restart;
283 
284 	bool tx_enabled;
285 	bool tx_active;
286 
287 	unsigned char signals;    /* serial signal states */
288 	int init_error;  /* initialization error */
289 
290 	unsigned char *tx_buf;
291 	int tx_count;
292 
293 	char *flag_buf;
294 	bool drop_rts_on_tx_done;
295 	struct	_input_signal_events	input_signal_events;
296 
297 	int dcd_chkcount;	/* check counts to prevent */
298 	int cts_chkcount;	/* too many IRQs if a signal */
299 	int dsr_chkcount;	/* is floating */
300 	int ri_chkcount;
301 
302 	char *bufs;		/* virtual address of DMA buffer lists */
303 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
304 
305 	unsigned int rbuf_count;
306 	struct slgt_desc *rbufs;
307 	unsigned int rbuf_current;
308 	unsigned int rbuf_index;
309 	unsigned int rbuf_fill_index;
310 	unsigned short rbuf_fill_count;
311 
312 	unsigned int tbuf_count;
313 	struct slgt_desc *tbufs;
314 	unsigned int tbuf_current;
315 	unsigned int tbuf_start;
316 
317 	unsigned char *tmp_rbuf;
318 	unsigned int tmp_rbuf_count;
319 
320 	/* SPPP/Cisco HDLC device parts */
321 
322 	int netcount;
323 	spinlock_t netlock;
324 #if SYNCLINK_GENERIC_HDLC
325 	struct net_device *netdev;
326 #endif
327 
328 };
329 
330 static MGSL_PARAMS default_params = {
331 	.mode            = MGSL_MODE_HDLC,
332 	.loopback        = 0,
333 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
334 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
335 	.clock_speed     = 0,
336 	.addr_filter     = 0xff,
337 	.crc_type        = HDLC_CRC_16_CCITT,
338 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
339 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
340 	.data_rate       = 9600,
341 	.data_bits       = 8,
342 	.stop_bits       = 1,
343 	.parity          = ASYNC_PARITY_NONE
344 };
345 
346 
347 #define BH_RECEIVE  1
348 #define BH_TRANSMIT 2
349 #define BH_STATUS   4
350 #define IO_PIN_SHUTDOWN_LIMIT 100
351 
352 #define DMABUFSIZE 256
353 #define DESC_LIST_SIZE 4096
354 
355 #define MASK_PARITY  BIT1
356 #define MASK_FRAMING BIT0
357 #define MASK_BREAK   BIT14
358 #define MASK_OVERRUN BIT4
359 
360 #define GSR   0x00 /* global status */
361 #define JCR   0x04 /* JTAG control */
362 #define IODR  0x08 /* GPIO direction */
363 #define IOER  0x0c /* GPIO interrupt enable */
364 #define IOVR  0x10 /* GPIO value */
365 #define IOSR  0x14 /* GPIO interrupt status */
366 #define TDR   0x80 /* tx data */
367 #define RDR   0x80 /* rx data */
368 #define TCR   0x82 /* tx control */
369 #define TIR   0x84 /* tx idle */
370 #define TPR   0x85 /* tx preamble */
371 #define RCR   0x86 /* rx control */
372 #define VCR   0x88 /* V.24 control */
373 #define CCR   0x89 /* clock control */
374 #define BDR   0x8a /* baud divisor */
375 #define SCR   0x8c /* serial control */
376 #define SSR   0x8e /* serial status */
377 #define RDCSR 0x90 /* rx DMA control/status */
378 #define TDCSR 0x94 /* tx DMA control/status */
379 #define RDDAR 0x98 /* rx DMA descriptor address */
380 #define TDDAR 0x9c /* tx DMA descriptor address */
381 #define XSR   0x40 /* extended sync pattern */
382 #define XCR   0x44 /* extended control */
383 
384 #define RXIDLE      BIT14
385 #define RXBREAK     BIT14
386 #define IRQ_TXDATA  BIT13
387 #define IRQ_TXIDLE  BIT12
388 #define IRQ_TXUNDER BIT11 /* HDLC */
389 #define IRQ_RXDATA  BIT10
390 #define IRQ_RXIDLE  BIT9  /* HDLC */
391 #define IRQ_RXBREAK BIT9  /* async */
392 #define IRQ_RXOVER  BIT8
393 #define IRQ_DSR     BIT7
394 #define IRQ_CTS     BIT6
395 #define IRQ_DCD     BIT5
396 #define IRQ_RI      BIT4
397 #define IRQ_ALL     0x3ff0
398 #define IRQ_MASTER  BIT0
399 
400 #define slgt_irq_on(info, mask) \
401 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
402 #define slgt_irq_off(info, mask) \
403 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
404 
405 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
406 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
407 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
408 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
409 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
410 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
411 
412 static void  msc_set_vcr(struct slgt_info *info);
413 
414 static int  startup(struct slgt_info *info);
415 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
416 static void shutdown(struct slgt_info *info);
417 static void program_hw(struct slgt_info *info);
418 static void change_params(struct slgt_info *info);
419 
420 static int  adapter_test(struct slgt_info *info);
421 
422 static void reset_port(struct slgt_info *info);
423 static void async_mode(struct slgt_info *info);
424 static void sync_mode(struct slgt_info *info);
425 
426 static void rx_stop(struct slgt_info *info);
427 static void rx_start(struct slgt_info *info);
428 static void reset_rbufs(struct slgt_info *info);
429 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
430 static bool rx_get_frame(struct slgt_info *info);
431 static bool rx_get_buf(struct slgt_info *info);
432 
433 static void tx_start(struct slgt_info *info);
434 static void tx_stop(struct slgt_info *info);
435 static void tx_set_idle(struct slgt_info *info);
436 static unsigned int tbuf_bytes(struct slgt_info *info);
437 static void reset_tbufs(struct slgt_info *info);
438 static void tdma_reset(struct slgt_info *info);
439 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
440 
441 static void get_signals(struct slgt_info *info);
442 static void set_signals(struct slgt_info *info);
443 static void set_rate(struct slgt_info *info, u32 data_rate);
444 
445 static void bh_transmit(struct slgt_info *info);
446 static void isr_txeom(struct slgt_info *info, unsigned short status);
447 
448 static void tx_timeout(struct timer_list *t);
449 static void rx_timeout(struct timer_list *t);
450 
451 /*
452  * ioctl handlers
453  */
454 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
455 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
456 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
457 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
458 static int  set_txidle(struct slgt_info *info, int idle_mode);
459 static int  tx_enable(struct slgt_info *info, int enable);
460 static int  tx_abort(struct slgt_info *info);
461 static int  rx_enable(struct slgt_info *info, int enable);
462 static int  modem_input_wait(struct slgt_info *info,int arg);
463 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
464 static int  get_interface(struct slgt_info *info, int __user *if_mode);
465 static int  set_interface(struct slgt_info *info, int if_mode);
466 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
467 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
468 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
469 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
470 static int  set_xsync(struct slgt_info *info, int if_mode);
471 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
472 static int  set_xctrl(struct slgt_info *info, int if_mode);
473 
474 /*
475  * driver functions
476  */
477 static void release_resources(struct slgt_info *info);
478 
479 /*
480  * DEBUG OUTPUT CODE
481  */
482 #ifndef DBGINFO
483 #define DBGINFO(fmt)
484 #endif
485 #ifndef DBGERR
486 #define DBGERR(fmt)
487 #endif
488 #ifndef DBGBH
489 #define DBGBH(fmt)
490 #endif
491 #ifndef DBGISR
492 #define DBGISR(fmt)
493 #endif
494 
495 #ifdef DBGDATA
496 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
497 {
498 	int i;
499 	int linecount;
500 	printk("%s %s data:\n",info->device_name, label);
501 	while(count) {
502 		linecount = (count > 16) ? 16 : count;
503 		for(i=0; i < linecount; i++)
504 			printk("%02X ",(unsigned char)data[i]);
505 		for(;i<17;i++)
506 			printk("   ");
507 		for(i=0;i<linecount;i++) {
508 			if (data[i]>=040 && data[i]<=0176)
509 				printk("%c",data[i]);
510 			else
511 				printk(".");
512 		}
513 		printk("\n");
514 		data  += linecount;
515 		count -= linecount;
516 	}
517 }
518 #else
519 #define DBGDATA(info, buf, size, label)
520 #endif
521 
522 #ifdef DBGTBUF
523 static void dump_tbufs(struct slgt_info *info)
524 {
525 	int i;
526 	printk("tbuf_current=%d\n", info->tbuf_current);
527 	for (i=0 ; i < info->tbuf_count ; i++) {
528 		printk("%d: count=%04X status=%04X\n",
529 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
530 	}
531 }
532 #else
533 #define DBGTBUF(info)
534 #endif
535 
536 #ifdef DBGRBUF
537 static void dump_rbufs(struct slgt_info *info)
538 {
539 	int i;
540 	printk("rbuf_current=%d\n", info->rbuf_current);
541 	for (i=0 ; i < info->rbuf_count ; i++) {
542 		printk("%d: count=%04X status=%04X\n",
543 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
544 	}
545 }
546 #else
547 #define DBGRBUF(info)
548 #endif
549 
550 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
551 {
552 #ifdef SANITY_CHECK
553 	if (!info) {
554 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
555 		return 1;
556 	}
557 	if (info->magic != MGSL_MAGIC) {
558 		printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
559 		return 1;
560 	}
561 #else
562 	if (!info)
563 		return 1;
564 #endif
565 	return 0;
566 }
567 
568 /*
569  * line discipline callback wrappers
570  *
571  * The wrappers maintain line discipline references
572  * while calling into the line discipline.
573  *
574  * ldisc_receive_buf  - pass receive data to line discipline
575  */
576 static void ldisc_receive_buf(struct tty_struct *tty,
577 			      const __u8 *data, char *flags, int count)
578 {
579 	struct tty_ldisc *ld;
580 	if (!tty)
581 		return;
582 	ld = tty_ldisc_ref(tty);
583 	if (ld) {
584 		if (ld->ops->receive_buf)
585 			ld->ops->receive_buf(tty, data, flags, count);
586 		tty_ldisc_deref(ld);
587 	}
588 }
589 
590 /* tty callbacks */
591 
592 static int open(struct tty_struct *tty, struct file *filp)
593 {
594 	struct slgt_info *info;
595 	int retval, line;
596 	unsigned long flags;
597 
598 	line = tty->index;
599 	if (line >= slgt_device_count) {
600 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
601 		return -ENODEV;
602 	}
603 
604 	info = slgt_device_list;
605 	while(info && info->line != line)
606 		info = info->next_device;
607 	if (sanity_check(info, tty->name, "open"))
608 		return -ENODEV;
609 	if (info->init_error) {
610 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
611 		return -ENODEV;
612 	}
613 
614 	tty->driver_data = info;
615 	info->port.tty = tty;
616 
617 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
618 
619 	mutex_lock(&info->port.mutex);
620 
621 	spin_lock_irqsave(&info->netlock, flags);
622 	if (info->netcount) {
623 		retval = -EBUSY;
624 		spin_unlock_irqrestore(&info->netlock, flags);
625 		mutex_unlock(&info->port.mutex);
626 		goto cleanup;
627 	}
628 	info->port.count++;
629 	spin_unlock_irqrestore(&info->netlock, flags);
630 
631 	if (info->port.count == 1) {
632 		/* 1st open on this device, init hardware */
633 		retval = startup(info);
634 		if (retval < 0) {
635 			mutex_unlock(&info->port.mutex);
636 			goto cleanup;
637 		}
638 	}
639 	mutex_unlock(&info->port.mutex);
640 	retval = block_til_ready(tty, filp, info);
641 	if (retval) {
642 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
643 		goto cleanup;
644 	}
645 
646 	retval = 0;
647 
648 cleanup:
649 	if (retval) {
650 		if (tty->count == 1)
651 			info->port.tty = NULL; /* tty layer will release tty struct */
652 		if(info->port.count)
653 			info->port.count--;
654 	}
655 
656 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
657 	return retval;
658 }
659 
660 static void close(struct tty_struct *tty, struct file *filp)
661 {
662 	struct slgt_info *info = tty->driver_data;
663 
664 	if (sanity_check(info, tty->name, "close"))
665 		return;
666 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
667 
668 	if (tty_port_close_start(&info->port, tty, filp) == 0)
669 		goto cleanup;
670 
671 	mutex_lock(&info->port.mutex);
672 	if (tty_port_initialized(&info->port))
673  		wait_until_sent(tty, info->timeout);
674 	flush_buffer(tty);
675 	tty_ldisc_flush(tty);
676 
677 	shutdown(info);
678 	mutex_unlock(&info->port.mutex);
679 
680 	tty_port_close_end(&info->port, tty);
681 	info->port.tty = NULL;
682 cleanup:
683 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
684 }
685 
686 static void hangup(struct tty_struct *tty)
687 {
688 	struct slgt_info *info = tty->driver_data;
689 	unsigned long flags;
690 
691 	if (sanity_check(info, tty->name, "hangup"))
692 		return;
693 	DBGINFO(("%s hangup\n", info->device_name));
694 
695 	flush_buffer(tty);
696 
697 	mutex_lock(&info->port.mutex);
698 	shutdown(info);
699 
700 	spin_lock_irqsave(&info->port.lock, flags);
701 	info->port.count = 0;
702 	info->port.tty = NULL;
703 	spin_unlock_irqrestore(&info->port.lock, flags);
704 	tty_port_set_active(&info->port, 0);
705 	mutex_unlock(&info->port.mutex);
706 
707 	wake_up_interruptible(&info->port.open_wait);
708 }
709 
710 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
711 {
712 	struct slgt_info *info = tty->driver_data;
713 	unsigned long flags;
714 
715 	DBGINFO(("%s set_termios\n", tty->driver->name));
716 
717 	change_params(info);
718 
719 	/* Handle transition to B0 status */
720 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
721 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
722 		spin_lock_irqsave(&info->lock,flags);
723 		set_signals(info);
724 		spin_unlock_irqrestore(&info->lock,flags);
725 	}
726 
727 	/* Handle transition away from B0 status */
728 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
729 		info->signals |= SerialSignal_DTR;
730 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
731 			info->signals |= SerialSignal_RTS;
732 		spin_lock_irqsave(&info->lock,flags);
733 	 	set_signals(info);
734 		spin_unlock_irqrestore(&info->lock,flags);
735 	}
736 
737 	/* Handle turning off CRTSCTS */
738 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
739 		tty->hw_stopped = 0;
740 		tx_release(tty);
741 	}
742 }
743 
744 static void update_tx_timer(struct slgt_info *info)
745 {
746 	/*
747 	 * use worst case speed of 1200bps to calculate transmit timeout
748 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
749 	 */
750 	if (info->params.mode == MGSL_MODE_HDLC) {
751 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
752 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
753 	}
754 }
755 
756 static int write(struct tty_struct *tty,
757 		 const unsigned char *buf, int count)
758 {
759 	int ret = 0;
760 	struct slgt_info *info = tty->driver_data;
761 	unsigned long flags;
762 
763 	if (sanity_check(info, tty->name, "write"))
764 		return -EIO;
765 
766 	DBGINFO(("%s write count=%d\n", info->device_name, count));
767 
768 	if (!info->tx_buf || (count > info->max_frame_size))
769 		return -EIO;
770 
771 	if (!count || tty->flow.stopped || tty->hw_stopped)
772 		return 0;
773 
774 	spin_lock_irqsave(&info->lock, flags);
775 
776 	if (info->tx_count) {
777 		/* send accumulated data from send_char() */
778 		if (!tx_load(info, info->tx_buf, info->tx_count))
779 			goto cleanup;
780 		info->tx_count = 0;
781 	}
782 
783 	if (tx_load(info, buf, count))
784 		ret = count;
785 
786 cleanup:
787 	spin_unlock_irqrestore(&info->lock, flags);
788 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
789 	return ret;
790 }
791 
792 static int put_char(struct tty_struct *tty, unsigned char ch)
793 {
794 	struct slgt_info *info = tty->driver_data;
795 	unsigned long flags;
796 	int ret = 0;
797 
798 	if (sanity_check(info, tty->name, "put_char"))
799 		return 0;
800 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
801 	if (!info->tx_buf)
802 		return 0;
803 	spin_lock_irqsave(&info->lock,flags);
804 	if (info->tx_count < info->max_frame_size) {
805 		info->tx_buf[info->tx_count++] = ch;
806 		ret = 1;
807 	}
808 	spin_unlock_irqrestore(&info->lock,flags);
809 	return ret;
810 }
811 
812 static void send_xchar(struct tty_struct *tty, char ch)
813 {
814 	struct slgt_info *info = tty->driver_data;
815 	unsigned long flags;
816 
817 	if (sanity_check(info, tty->name, "send_xchar"))
818 		return;
819 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
820 	info->x_char = ch;
821 	if (ch) {
822 		spin_lock_irqsave(&info->lock,flags);
823 		if (!info->tx_enabled)
824 		 	tx_start(info);
825 		spin_unlock_irqrestore(&info->lock,flags);
826 	}
827 }
828 
829 static void wait_until_sent(struct tty_struct *tty, int timeout)
830 {
831 	struct slgt_info *info = tty->driver_data;
832 	unsigned long orig_jiffies, char_time;
833 
834 	if (!info )
835 		return;
836 	if (sanity_check(info, tty->name, "wait_until_sent"))
837 		return;
838 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
839 	if (!tty_port_initialized(&info->port))
840 		goto exit;
841 
842 	orig_jiffies = jiffies;
843 
844 	/* Set check interval to 1/5 of estimated time to
845 	 * send a character, and make it at least 1. The check
846 	 * interval should also be less than the timeout.
847 	 * Note: use tight timings here to satisfy the NIST-PCTS.
848 	 */
849 
850 	if (info->params.data_rate) {
851 	       	char_time = info->timeout/(32 * 5);
852 		if (!char_time)
853 			char_time++;
854 	} else
855 		char_time = 1;
856 
857 	if (timeout)
858 		char_time = min_t(unsigned long, char_time, timeout);
859 
860 	while (info->tx_active) {
861 		msleep_interruptible(jiffies_to_msecs(char_time));
862 		if (signal_pending(current))
863 			break;
864 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
865 			break;
866 	}
867 exit:
868 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
869 }
870 
871 static unsigned int write_room(struct tty_struct *tty)
872 {
873 	struct slgt_info *info = tty->driver_data;
874 	unsigned int ret;
875 
876 	if (sanity_check(info, tty->name, "write_room"))
877 		return 0;
878 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
879 	DBGINFO(("%s write_room=%u\n", info->device_name, ret));
880 	return ret;
881 }
882 
883 static void flush_chars(struct tty_struct *tty)
884 {
885 	struct slgt_info *info = tty->driver_data;
886 	unsigned long flags;
887 
888 	if (sanity_check(info, tty->name, "flush_chars"))
889 		return;
890 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
891 
892 	if (info->tx_count <= 0 || tty->flow.stopped ||
893 	    tty->hw_stopped || !info->tx_buf)
894 		return;
895 
896 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
897 
898 	spin_lock_irqsave(&info->lock,flags);
899 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
900 		info->tx_count = 0;
901 	spin_unlock_irqrestore(&info->lock,flags);
902 }
903 
904 static void flush_buffer(struct tty_struct *tty)
905 {
906 	struct slgt_info *info = tty->driver_data;
907 	unsigned long flags;
908 
909 	if (sanity_check(info, tty->name, "flush_buffer"))
910 		return;
911 	DBGINFO(("%s flush_buffer\n", info->device_name));
912 
913 	spin_lock_irqsave(&info->lock, flags);
914 	info->tx_count = 0;
915 	spin_unlock_irqrestore(&info->lock, flags);
916 
917 	tty_wakeup(tty);
918 }
919 
920 /*
921  * throttle (stop) transmitter
922  */
923 static void tx_hold(struct tty_struct *tty)
924 {
925 	struct slgt_info *info = tty->driver_data;
926 	unsigned long flags;
927 
928 	if (sanity_check(info, tty->name, "tx_hold"))
929 		return;
930 	DBGINFO(("%s tx_hold\n", info->device_name));
931 	spin_lock_irqsave(&info->lock,flags);
932 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
933 	 	tx_stop(info);
934 	spin_unlock_irqrestore(&info->lock,flags);
935 }
936 
937 /*
938  * release (start) transmitter
939  */
940 static void tx_release(struct tty_struct *tty)
941 {
942 	struct slgt_info *info = tty->driver_data;
943 	unsigned long flags;
944 
945 	if (sanity_check(info, tty->name, "tx_release"))
946 		return;
947 	DBGINFO(("%s tx_release\n", info->device_name));
948 	spin_lock_irqsave(&info->lock, flags);
949 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
950 		info->tx_count = 0;
951 	spin_unlock_irqrestore(&info->lock, flags);
952 }
953 
954 /*
955  * Service an IOCTL request
956  *
957  * Arguments
958  *
959  * 	tty	pointer to tty instance data
960  * 	cmd	IOCTL command code
961  * 	arg	command argument/context
962  *
963  * Return 0 if success, otherwise error code
964  */
965 static int ioctl(struct tty_struct *tty,
966 		 unsigned int cmd, unsigned long arg)
967 {
968 	struct slgt_info *info = tty->driver_data;
969 	void __user *argp = (void __user *)arg;
970 	int ret;
971 
972 	if (sanity_check(info, tty->name, "ioctl"))
973 		return -ENODEV;
974 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
975 
976 	if (cmd != TIOCMIWAIT) {
977 		if (tty_io_error(tty))
978 		    return -EIO;
979 	}
980 
981 	switch (cmd) {
982 	case MGSL_IOCWAITEVENT:
983 		return wait_mgsl_event(info, argp);
984 	case TIOCMIWAIT:
985 		return modem_input_wait(info,(int)arg);
986 	case MGSL_IOCSGPIO:
987 		return set_gpio(info, argp);
988 	case MGSL_IOCGGPIO:
989 		return get_gpio(info, argp);
990 	case MGSL_IOCWAITGPIO:
991 		return wait_gpio(info, argp);
992 	case MGSL_IOCGXSYNC:
993 		return get_xsync(info, argp);
994 	case MGSL_IOCSXSYNC:
995 		return set_xsync(info, (int)arg);
996 	case MGSL_IOCGXCTRL:
997 		return get_xctrl(info, argp);
998 	case MGSL_IOCSXCTRL:
999 		return set_xctrl(info, (int)arg);
1000 	}
1001 	mutex_lock(&info->port.mutex);
1002 	switch (cmd) {
1003 	case MGSL_IOCGPARAMS:
1004 		ret = get_params(info, argp);
1005 		break;
1006 	case MGSL_IOCSPARAMS:
1007 		ret = set_params(info, argp);
1008 		break;
1009 	case MGSL_IOCGTXIDLE:
1010 		ret = get_txidle(info, argp);
1011 		break;
1012 	case MGSL_IOCSTXIDLE:
1013 		ret = set_txidle(info, (int)arg);
1014 		break;
1015 	case MGSL_IOCTXENABLE:
1016 		ret = tx_enable(info, (int)arg);
1017 		break;
1018 	case MGSL_IOCRXENABLE:
1019 		ret = rx_enable(info, (int)arg);
1020 		break;
1021 	case MGSL_IOCTXABORT:
1022 		ret = tx_abort(info);
1023 		break;
1024 	case MGSL_IOCGSTATS:
1025 		ret = get_stats(info, argp);
1026 		break;
1027 	case MGSL_IOCGIF:
1028 		ret = get_interface(info, argp);
1029 		break;
1030 	case MGSL_IOCSIF:
1031 		ret = set_interface(info,(int)arg);
1032 		break;
1033 	default:
1034 		ret = -ENOIOCTLCMD;
1035 	}
1036 	mutex_unlock(&info->port.mutex);
1037 	return ret;
1038 }
1039 
1040 static int get_icount(struct tty_struct *tty,
1041 				struct serial_icounter_struct *icount)
1042 
1043 {
1044 	struct slgt_info *info = tty->driver_data;
1045 	struct mgsl_icount cnow;	/* kernel counter temps */
1046 	unsigned long flags;
1047 
1048 	spin_lock_irqsave(&info->lock,flags);
1049 	cnow = info->icount;
1050 	spin_unlock_irqrestore(&info->lock,flags);
1051 
1052 	icount->cts = cnow.cts;
1053 	icount->dsr = cnow.dsr;
1054 	icount->rng = cnow.rng;
1055 	icount->dcd = cnow.dcd;
1056 	icount->rx = cnow.rx;
1057 	icount->tx = cnow.tx;
1058 	icount->frame = cnow.frame;
1059 	icount->overrun = cnow.overrun;
1060 	icount->parity = cnow.parity;
1061 	icount->brk = cnow.brk;
1062 	icount->buf_overrun = cnow.buf_overrun;
1063 
1064 	return 0;
1065 }
1066 
1067 /*
1068  * support for 32 bit ioctl calls on 64 bit systems
1069  */
1070 #ifdef CONFIG_COMPAT
1071 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1072 {
1073 	struct MGSL_PARAMS32 tmp_params;
1074 
1075 	DBGINFO(("%s get_params32\n", info->device_name));
1076 	memset(&tmp_params, 0, sizeof(tmp_params));
1077 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1078 	tmp_params.loopback        = info->params.loopback;
1079 	tmp_params.flags           = info->params.flags;
1080 	tmp_params.encoding        = info->params.encoding;
1081 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1082 	tmp_params.addr_filter     = info->params.addr_filter;
1083 	tmp_params.crc_type        = info->params.crc_type;
1084 	tmp_params.preamble_length = info->params.preamble_length;
1085 	tmp_params.preamble        = info->params.preamble;
1086 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1087 	tmp_params.data_bits       = info->params.data_bits;
1088 	tmp_params.stop_bits       = info->params.stop_bits;
1089 	tmp_params.parity          = info->params.parity;
1090 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1091 		return -EFAULT;
1092 	return 0;
1093 }
1094 
1095 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1096 {
1097 	struct MGSL_PARAMS32 tmp_params;
1098 
1099 	DBGINFO(("%s set_params32\n", info->device_name));
1100 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1101 		return -EFAULT;
1102 
1103 	spin_lock(&info->lock);
1104 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1105 		info->base_clock = tmp_params.clock_speed;
1106 	} else {
1107 		info->params.mode            = tmp_params.mode;
1108 		info->params.loopback        = tmp_params.loopback;
1109 		info->params.flags           = tmp_params.flags;
1110 		info->params.encoding        = tmp_params.encoding;
1111 		info->params.clock_speed     = tmp_params.clock_speed;
1112 		info->params.addr_filter     = tmp_params.addr_filter;
1113 		info->params.crc_type        = tmp_params.crc_type;
1114 		info->params.preamble_length = tmp_params.preamble_length;
1115 		info->params.preamble        = tmp_params.preamble;
1116 		info->params.data_rate       = tmp_params.data_rate;
1117 		info->params.data_bits       = tmp_params.data_bits;
1118 		info->params.stop_bits       = tmp_params.stop_bits;
1119 		info->params.parity          = tmp_params.parity;
1120 	}
1121 	spin_unlock(&info->lock);
1122 
1123 	program_hw(info);
1124 
1125 	return 0;
1126 }
1127 
1128 static long slgt_compat_ioctl(struct tty_struct *tty,
1129 			 unsigned int cmd, unsigned long arg)
1130 {
1131 	struct slgt_info *info = tty->driver_data;
1132 	int rc;
1133 
1134 	if (sanity_check(info, tty->name, "compat_ioctl"))
1135 		return -ENODEV;
1136 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1137 
1138 	switch (cmd) {
1139 	case MGSL_IOCSPARAMS32:
1140 		rc = set_params32(info, compat_ptr(arg));
1141 		break;
1142 
1143 	case MGSL_IOCGPARAMS32:
1144 		rc = get_params32(info, compat_ptr(arg));
1145 		break;
1146 
1147 	case MGSL_IOCGPARAMS:
1148 	case MGSL_IOCSPARAMS:
1149 	case MGSL_IOCGTXIDLE:
1150 	case MGSL_IOCGSTATS:
1151 	case MGSL_IOCWAITEVENT:
1152 	case MGSL_IOCGIF:
1153 	case MGSL_IOCSGPIO:
1154 	case MGSL_IOCGGPIO:
1155 	case MGSL_IOCWAITGPIO:
1156 	case MGSL_IOCGXSYNC:
1157 	case MGSL_IOCGXCTRL:
1158 		rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1159 		break;
1160 	default:
1161 		rc = ioctl(tty, cmd, arg);
1162 	}
1163 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1164 	return rc;
1165 }
1166 #else
1167 #define slgt_compat_ioctl NULL
1168 #endif /* ifdef CONFIG_COMPAT */
1169 
1170 /*
1171  * proc fs support
1172  */
1173 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1174 {
1175 	char stat_buf[30];
1176 	unsigned long flags;
1177 
1178 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1179 		      info->device_name, info->phys_reg_addr,
1180 		      info->irq_level, info->max_frame_size);
1181 
1182 	/* output current serial signal states */
1183 	spin_lock_irqsave(&info->lock,flags);
1184 	get_signals(info);
1185 	spin_unlock_irqrestore(&info->lock,flags);
1186 
1187 	stat_buf[0] = 0;
1188 	stat_buf[1] = 0;
1189 	if (info->signals & SerialSignal_RTS)
1190 		strcat(stat_buf, "|RTS");
1191 	if (info->signals & SerialSignal_CTS)
1192 		strcat(stat_buf, "|CTS");
1193 	if (info->signals & SerialSignal_DTR)
1194 		strcat(stat_buf, "|DTR");
1195 	if (info->signals & SerialSignal_DSR)
1196 		strcat(stat_buf, "|DSR");
1197 	if (info->signals & SerialSignal_DCD)
1198 		strcat(stat_buf, "|CD");
1199 	if (info->signals & SerialSignal_RI)
1200 		strcat(stat_buf, "|RI");
1201 
1202 	if (info->params.mode != MGSL_MODE_ASYNC) {
1203 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1204 			       info->icount.txok, info->icount.rxok);
1205 		if (info->icount.txunder)
1206 			seq_printf(m, " txunder:%d", info->icount.txunder);
1207 		if (info->icount.txabort)
1208 			seq_printf(m, " txabort:%d", info->icount.txabort);
1209 		if (info->icount.rxshort)
1210 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1211 		if (info->icount.rxlong)
1212 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1213 		if (info->icount.rxover)
1214 			seq_printf(m, " rxover:%d", info->icount.rxover);
1215 		if (info->icount.rxcrc)
1216 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1217 	} else {
1218 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1219 			       info->icount.tx, info->icount.rx);
1220 		if (info->icount.frame)
1221 			seq_printf(m, " fe:%d", info->icount.frame);
1222 		if (info->icount.parity)
1223 			seq_printf(m, " pe:%d", info->icount.parity);
1224 		if (info->icount.brk)
1225 			seq_printf(m, " brk:%d", info->icount.brk);
1226 		if (info->icount.overrun)
1227 			seq_printf(m, " oe:%d", info->icount.overrun);
1228 	}
1229 
1230 	/* Append serial signal status to end */
1231 	seq_printf(m, " %s\n", stat_buf+1);
1232 
1233 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1234 		       info->tx_active,info->bh_requested,info->bh_running,
1235 		       info->pending_bh);
1236 }
1237 
1238 /* Called to print information about devices
1239  */
1240 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1241 {
1242 	struct slgt_info *info;
1243 
1244 	seq_puts(m, "synclink_gt driver\n");
1245 
1246 	info = slgt_device_list;
1247 	while( info ) {
1248 		line_info(m, info);
1249 		info = info->next_device;
1250 	}
1251 	return 0;
1252 }
1253 
1254 /*
1255  * return count of bytes in transmit buffer
1256  */
1257 static unsigned int chars_in_buffer(struct tty_struct *tty)
1258 {
1259 	struct slgt_info *info = tty->driver_data;
1260 	unsigned int count;
1261 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1262 		return 0;
1263 	count = tbuf_bytes(info);
1264 	DBGINFO(("%s chars_in_buffer()=%u\n", info->device_name, count));
1265 	return count;
1266 }
1267 
1268 /*
1269  * signal remote device to throttle send data (our receive data)
1270  */
1271 static void throttle(struct tty_struct * tty)
1272 {
1273 	struct slgt_info *info = tty->driver_data;
1274 	unsigned long flags;
1275 
1276 	if (sanity_check(info, tty->name, "throttle"))
1277 		return;
1278 	DBGINFO(("%s throttle\n", info->device_name));
1279 	if (I_IXOFF(tty))
1280 		send_xchar(tty, STOP_CHAR(tty));
1281 	if (C_CRTSCTS(tty)) {
1282 		spin_lock_irqsave(&info->lock,flags);
1283 		info->signals &= ~SerialSignal_RTS;
1284 		set_signals(info);
1285 		spin_unlock_irqrestore(&info->lock,flags);
1286 	}
1287 }
1288 
1289 /*
1290  * signal remote device to stop throttling send data (our receive data)
1291  */
1292 static void unthrottle(struct tty_struct * tty)
1293 {
1294 	struct slgt_info *info = tty->driver_data;
1295 	unsigned long flags;
1296 
1297 	if (sanity_check(info, tty->name, "unthrottle"))
1298 		return;
1299 	DBGINFO(("%s unthrottle\n", info->device_name));
1300 	if (I_IXOFF(tty)) {
1301 		if (info->x_char)
1302 			info->x_char = 0;
1303 		else
1304 			send_xchar(tty, START_CHAR(tty));
1305 	}
1306 	if (C_CRTSCTS(tty)) {
1307 		spin_lock_irqsave(&info->lock,flags);
1308 		info->signals |= SerialSignal_RTS;
1309 		set_signals(info);
1310 		spin_unlock_irqrestore(&info->lock,flags);
1311 	}
1312 }
1313 
1314 /*
1315  * set or clear transmit break condition
1316  * break_state	-1=set break condition, 0=clear
1317  */
1318 static int set_break(struct tty_struct *tty, int break_state)
1319 {
1320 	struct slgt_info *info = tty->driver_data;
1321 	unsigned short value;
1322 	unsigned long flags;
1323 
1324 	if (sanity_check(info, tty->name, "set_break"))
1325 		return -EINVAL;
1326 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1327 
1328 	spin_lock_irqsave(&info->lock,flags);
1329 	value = rd_reg16(info, TCR);
1330  	if (break_state == -1)
1331 		value |= BIT6;
1332 	else
1333 		value &= ~BIT6;
1334 	wr_reg16(info, TCR, value);
1335 	spin_unlock_irqrestore(&info->lock,flags);
1336 	return 0;
1337 }
1338 
1339 #if SYNCLINK_GENERIC_HDLC
1340 
1341 /**
1342  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1343  * @dev:      pointer to network device structure
1344  * @encoding: serial encoding setting
1345  * @parity:   FCS setting
1346  *
1347  * Set encoding and frame check sequence (FCS) options.
1348  *
1349  * Return: 0 if success, otherwise error code
1350  */
1351 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1352 			  unsigned short parity)
1353 {
1354 	struct slgt_info *info = dev_to_port(dev);
1355 	unsigned char  new_encoding;
1356 	unsigned short new_crctype;
1357 
1358 	/* return error if TTY interface open */
1359 	if (info->port.count)
1360 		return -EBUSY;
1361 
1362 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1363 
1364 	switch (encoding)
1365 	{
1366 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1367 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1368 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1369 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1370 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1371 	default: return -EINVAL;
1372 	}
1373 
1374 	switch (parity)
1375 	{
1376 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1377 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1378 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1379 	default: return -EINVAL;
1380 	}
1381 
1382 	info->params.encoding = new_encoding;
1383 	info->params.crc_type = new_crctype;
1384 
1385 	/* if network interface up, reprogram hardware */
1386 	if (info->netcount)
1387 		program_hw(info);
1388 
1389 	return 0;
1390 }
1391 
1392 /**
1393  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1394  * @skb: socket buffer containing HDLC frame
1395  * @dev: pointer to network device structure
1396  */
1397 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1398 				      struct net_device *dev)
1399 {
1400 	struct slgt_info *info = dev_to_port(dev);
1401 	unsigned long flags;
1402 
1403 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1404 
1405 	if (!skb->len)
1406 		return NETDEV_TX_OK;
1407 
1408 	/* stop sending until this frame completes */
1409 	netif_stop_queue(dev);
1410 
1411 	/* update network statistics */
1412 	dev->stats.tx_packets++;
1413 	dev->stats.tx_bytes += skb->len;
1414 
1415 	/* save start time for transmit timeout detection */
1416 	netif_trans_update(dev);
1417 
1418 	spin_lock_irqsave(&info->lock, flags);
1419 	tx_load(info, skb->data, skb->len);
1420 	spin_unlock_irqrestore(&info->lock, flags);
1421 
1422 	/* done with socket buffer, so free it */
1423 	dev_kfree_skb(skb);
1424 
1425 	return NETDEV_TX_OK;
1426 }
1427 
1428 /**
1429  * hdlcdev_open - called by network layer when interface enabled
1430  * @dev: pointer to network device structure
1431  *
1432  * Claim resources and initialize hardware.
1433  *
1434  * Return: 0 if success, otherwise error code
1435  */
1436 static int hdlcdev_open(struct net_device *dev)
1437 {
1438 	struct slgt_info *info = dev_to_port(dev);
1439 	int rc;
1440 	unsigned long flags;
1441 
1442 	if (!try_module_get(THIS_MODULE))
1443 		return -EBUSY;
1444 
1445 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1446 
1447 	/* generic HDLC layer open processing */
1448 	rc = hdlc_open(dev);
1449 	if (rc)
1450 		return rc;
1451 
1452 	/* arbitrate between network and tty opens */
1453 	spin_lock_irqsave(&info->netlock, flags);
1454 	if (info->port.count != 0 || info->netcount != 0) {
1455 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1456 		spin_unlock_irqrestore(&info->netlock, flags);
1457 		return -EBUSY;
1458 	}
1459 	info->netcount=1;
1460 	spin_unlock_irqrestore(&info->netlock, flags);
1461 
1462 	/* claim resources and init adapter */
1463 	if ((rc = startup(info)) != 0) {
1464 		spin_lock_irqsave(&info->netlock, flags);
1465 		info->netcount=0;
1466 		spin_unlock_irqrestore(&info->netlock, flags);
1467 		return rc;
1468 	}
1469 
1470 	/* assert RTS and DTR, apply hardware settings */
1471 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1472 	program_hw(info);
1473 
1474 	/* enable network layer transmit */
1475 	netif_trans_update(dev);
1476 	netif_start_queue(dev);
1477 
1478 	/* inform generic HDLC layer of current DCD status */
1479 	spin_lock_irqsave(&info->lock, flags);
1480 	get_signals(info);
1481 	spin_unlock_irqrestore(&info->lock, flags);
1482 	if (info->signals & SerialSignal_DCD)
1483 		netif_carrier_on(dev);
1484 	else
1485 		netif_carrier_off(dev);
1486 	return 0;
1487 }
1488 
1489 /**
1490  * hdlcdev_close - called by network layer when interface is disabled
1491  * @dev:  pointer to network device structure
1492  *
1493  * Shutdown hardware and release resources.
1494  *
1495  * Return: 0 if success, otherwise error code
1496  */
1497 static int hdlcdev_close(struct net_device *dev)
1498 {
1499 	struct slgt_info *info = dev_to_port(dev);
1500 	unsigned long flags;
1501 
1502 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1503 
1504 	netif_stop_queue(dev);
1505 
1506 	/* shutdown adapter and release resources */
1507 	shutdown(info);
1508 
1509 	hdlc_close(dev);
1510 
1511 	spin_lock_irqsave(&info->netlock, flags);
1512 	info->netcount=0;
1513 	spin_unlock_irqrestore(&info->netlock, flags);
1514 
1515 	module_put(THIS_MODULE);
1516 	return 0;
1517 }
1518 
1519 /**
1520  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1521  * @dev: pointer to network device structure
1522  * @ifr: pointer to network interface request structure
1523  * @cmd: IOCTL command code
1524  *
1525  * Return: 0 if success, otherwise error code
1526  */
1527 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1528 {
1529 	const size_t size = sizeof(sync_serial_settings);
1530 	sync_serial_settings new_line;
1531 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1532 	struct slgt_info *info = dev_to_port(dev);
1533 	unsigned int flags;
1534 
1535 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1536 
1537 	/* return error if TTY interface open */
1538 	if (info->port.count)
1539 		return -EBUSY;
1540 
1541 	if (cmd != SIOCWANDEV)
1542 		return hdlc_ioctl(dev, ifr, cmd);
1543 
1544 	memset(&new_line, 0, sizeof(new_line));
1545 
1546 	switch(ifr->ifr_settings.type) {
1547 	case IF_GET_IFACE: /* return current sync_serial_settings */
1548 
1549 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1550 		if (ifr->ifr_settings.size < size) {
1551 			ifr->ifr_settings.size = size; /* data size wanted */
1552 			return -ENOBUFS;
1553 		}
1554 
1555 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1556 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1557 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1558 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1559 
1560 		switch (flags){
1561 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1562 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1563 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1564 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1565 		default: new_line.clock_type = CLOCK_DEFAULT;
1566 		}
1567 
1568 		new_line.clock_rate = info->params.clock_speed;
1569 		new_line.loopback   = info->params.loopback ? 1:0;
1570 
1571 		if (copy_to_user(line, &new_line, size))
1572 			return -EFAULT;
1573 		return 0;
1574 
1575 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1576 
1577 		if(!capable(CAP_NET_ADMIN))
1578 			return -EPERM;
1579 		if (copy_from_user(&new_line, line, size))
1580 			return -EFAULT;
1581 
1582 		switch (new_line.clock_type)
1583 		{
1584 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1585 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1586 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1587 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1588 		case CLOCK_DEFAULT:  flags = info->params.flags &
1589 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1590 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1591 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1592 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1593 		default: return -EINVAL;
1594 		}
1595 
1596 		if (new_line.loopback != 0 && new_line.loopback != 1)
1597 			return -EINVAL;
1598 
1599 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1600 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1601 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1602 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1603 		info->params.flags |= flags;
1604 
1605 		info->params.loopback = new_line.loopback;
1606 
1607 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1608 			info->params.clock_speed = new_line.clock_rate;
1609 		else
1610 			info->params.clock_speed = 0;
1611 
1612 		/* if network interface up, reprogram hardware */
1613 		if (info->netcount)
1614 			program_hw(info);
1615 		return 0;
1616 
1617 	default:
1618 		return hdlc_ioctl(dev, ifr, cmd);
1619 	}
1620 }
1621 
1622 /**
1623  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1624  * @dev: pointer to network device structure
1625  * @txqueue: unused
1626  */
1627 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1628 {
1629 	struct slgt_info *info = dev_to_port(dev);
1630 	unsigned long flags;
1631 
1632 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1633 
1634 	dev->stats.tx_errors++;
1635 	dev->stats.tx_aborted_errors++;
1636 
1637 	spin_lock_irqsave(&info->lock,flags);
1638 	tx_stop(info);
1639 	spin_unlock_irqrestore(&info->lock,flags);
1640 
1641 	netif_wake_queue(dev);
1642 }
1643 
1644 /**
1645  * hdlcdev_tx_done - called by device driver when transmit completes
1646  * @info: pointer to device instance information
1647  *
1648  * Reenable network layer transmit if stopped.
1649  */
1650 static void hdlcdev_tx_done(struct slgt_info *info)
1651 {
1652 	if (netif_queue_stopped(info->netdev))
1653 		netif_wake_queue(info->netdev);
1654 }
1655 
1656 /**
1657  * hdlcdev_rx - called by device driver when frame received
1658  * @info: pointer to device instance information
1659  * @buf:  pointer to buffer contianing frame data
1660  * @size: count of data bytes in buf
1661  *
1662  * Pass frame to network layer.
1663  */
1664 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1665 {
1666 	struct sk_buff *skb = dev_alloc_skb(size);
1667 	struct net_device *dev = info->netdev;
1668 
1669 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1670 
1671 	if (skb == NULL) {
1672 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1673 		dev->stats.rx_dropped++;
1674 		return;
1675 	}
1676 
1677 	skb_put_data(skb, buf, size);
1678 
1679 	skb->protocol = hdlc_type_trans(skb, dev);
1680 
1681 	dev->stats.rx_packets++;
1682 	dev->stats.rx_bytes += size;
1683 
1684 	netif_rx(skb);
1685 }
1686 
1687 static const struct net_device_ops hdlcdev_ops = {
1688 	.ndo_open       = hdlcdev_open,
1689 	.ndo_stop       = hdlcdev_close,
1690 	.ndo_start_xmit = hdlc_start_xmit,
1691 	.ndo_do_ioctl   = hdlcdev_ioctl,
1692 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1693 };
1694 
1695 /**
1696  * hdlcdev_init - called by device driver when adding device instance
1697  * @info: pointer to device instance information
1698  *
1699  * Do generic HDLC initialization.
1700  *
1701  * Return: 0 if success, otherwise error code
1702  */
1703 static int hdlcdev_init(struct slgt_info *info)
1704 {
1705 	int rc;
1706 	struct net_device *dev;
1707 	hdlc_device *hdlc;
1708 
1709 	/* allocate and initialize network and HDLC layer objects */
1710 
1711 	dev = alloc_hdlcdev(info);
1712 	if (!dev) {
1713 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1714 		return -ENOMEM;
1715 	}
1716 
1717 	/* for network layer reporting purposes only */
1718 	dev->mem_start = info->phys_reg_addr;
1719 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1720 	dev->irq       = info->irq_level;
1721 
1722 	/* network layer callbacks and settings */
1723 	dev->netdev_ops	    = &hdlcdev_ops;
1724 	dev->watchdog_timeo = 10 * HZ;
1725 	dev->tx_queue_len   = 50;
1726 
1727 	/* generic HDLC layer callbacks and settings */
1728 	hdlc         = dev_to_hdlc(dev);
1729 	hdlc->attach = hdlcdev_attach;
1730 	hdlc->xmit   = hdlcdev_xmit;
1731 
1732 	/* register objects with HDLC layer */
1733 	rc = register_hdlc_device(dev);
1734 	if (rc) {
1735 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1736 		free_netdev(dev);
1737 		return rc;
1738 	}
1739 
1740 	info->netdev = dev;
1741 	return 0;
1742 }
1743 
1744 /**
1745  * hdlcdev_exit - called by device driver when removing device instance
1746  * @info: pointer to device instance information
1747  *
1748  * Do generic HDLC cleanup.
1749  */
1750 static void hdlcdev_exit(struct slgt_info *info)
1751 {
1752 	unregister_hdlc_device(info->netdev);
1753 	free_netdev(info->netdev);
1754 	info->netdev = NULL;
1755 }
1756 
1757 #endif /* ifdef CONFIG_HDLC */
1758 
1759 /*
1760  * get async data from rx DMA buffers
1761  */
1762 static void rx_async(struct slgt_info *info)
1763 {
1764  	struct mgsl_icount *icount = &info->icount;
1765 	unsigned int start, end;
1766 	unsigned char *p;
1767 	unsigned char status;
1768 	struct slgt_desc *bufs = info->rbufs;
1769 	int i, count;
1770 	int chars = 0;
1771 	int stat;
1772 	unsigned char ch;
1773 
1774 	start = end = info->rbuf_current;
1775 
1776 	while(desc_complete(bufs[end])) {
1777 		count = desc_count(bufs[end]) - info->rbuf_index;
1778 		p     = bufs[end].buf + info->rbuf_index;
1779 
1780 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1781 		DBGDATA(info, p, count, "rx");
1782 
1783 		for(i=0 ; i < count; i+=2, p+=2) {
1784 			ch = *p;
1785 			icount->rx++;
1786 
1787 			stat = 0;
1788 
1789 			status = *(p + 1) & (BIT1 + BIT0);
1790 			if (status) {
1791 				if (status & BIT1)
1792 					icount->parity++;
1793 				else if (status & BIT0)
1794 					icount->frame++;
1795 				/* discard char if tty control flags say so */
1796 				if (status & info->ignore_status_mask)
1797 					continue;
1798 				if (status & BIT1)
1799 					stat = TTY_PARITY;
1800 				else if (status & BIT0)
1801 					stat = TTY_FRAME;
1802 			}
1803 			tty_insert_flip_char(&info->port, ch, stat);
1804 			chars++;
1805 		}
1806 
1807 		if (i < count) {
1808 			/* receive buffer not completed */
1809 			info->rbuf_index += i;
1810 			mod_timer(&info->rx_timer, jiffies + 1);
1811 			break;
1812 		}
1813 
1814 		info->rbuf_index = 0;
1815 		free_rbufs(info, end, end);
1816 
1817 		if (++end == info->rbuf_count)
1818 			end = 0;
1819 
1820 		/* if entire list searched then no frame available */
1821 		if (end == start)
1822 			break;
1823 	}
1824 
1825 	if (chars)
1826 		tty_flip_buffer_push(&info->port);
1827 }
1828 
1829 /*
1830  * return next bottom half action to perform
1831  */
1832 static int bh_action(struct slgt_info *info)
1833 {
1834 	unsigned long flags;
1835 	int rc;
1836 
1837 	spin_lock_irqsave(&info->lock,flags);
1838 
1839 	if (info->pending_bh & BH_RECEIVE) {
1840 		info->pending_bh &= ~BH_RECEIVE;
1841 		rc = BH_RECEIVE;
1842 	} else if (info->pending_bh & BH_TRANSMIT) {
1843 		info->pending_bh &= ~BH_TRANSMIT;
1844 		rc = BH_TRANSMIT;
1845 	} else if (info->pending_bh & BH_STATUS) {
1846 		info->pending_bh &= ~BH_STATUS;
1847 		rc = BH_STATUS;
1848 	} else {
1849 		/* Mark BH routine as complete */
1850 		info->bh_running = false;
1851 		info->bh_requested = false;
1852 		rc = 0;
1853 	}
1854 
1855 	spin_unlock_irqrestore(&info->lock,flags);
1856 
1857 	return rc;
1858 }
1859 
1860 /*
1861  * perform bottom half processing
1862  */
1863 static void bh_handler(struct work_struct *work)
1864 {
1865 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1866 	int action;
1867 
1868 	info->bh_running = true;
1869 
1870 	while((action = bh_action(info))) {
1871 		switch (action) {
1872 		case BH_RECEIVE:
1873 			DBGBH(("%s bh receive\n", info->device_name));
1874 			switch(info->params.mode) {
1875 			case MGSL_MODE_ASYNC:
1876 				rx_async(info);
1877 				break;
1878 			case MGSL_MODE_HDLC:
1879 				while(rx_get_frame(info));
1880 				break;
1881 			case MGSL_MODE_RAW:
1882 			case MGSL_MODE_MONOSYNC:
1883 			case MGSL_MODE_BISYNC:
1884 			case MGSL_MODE_XSYNC:
1885 				while(rx_get_buf(info));
1886 				break;
1887 			}
1888 			/* restart receiver if rx DMA buffers exhausted */
1889 			if (info->rx_restart)
1890 				rx_start(info);
1891 			break;
1892 		case BH_TRANSMIT:
1893 			bh_transmit(info);
1894 			break;
1895 		case BH_STATUS:
1896 			DBGBH(("%s bh status\n", info->device_name));
1897 			info->ri_chkcount = 0;
1898 			info->dsr_chkcount = 0;
1899 			info->dcd_chkcount = 0;
1900 			info->cts_chkcount = 0;
1901 			break;
1902 		default:
1903 			DBGBH(("%s unknown action\n", info->device_name));
1904 			break;
1905 		}
1906 	}
1907 	DBGBH(("%s bh_handler exit\n", info->device_name));
1908 }
1909 
1910 static void bh_transmit(struct slgt_info *info)
1911 {
1912 	struct tty_struct *tty = info->port.tty;
1913 
1914 	DBGBH(("%s bh_transmit\n", info->device_name));
1915 	if (tty)
1916 		tty_wakeup(tty);
1917 }
1918 
1919 static void dsr_change(struct slgt_info *info, unsigned short status)
1920 {
1921 	if (status & BIT3) {
1922 		info->signals |= SerialSignal_DSR;
1923 		info->input_signal_events.dsr_up++;
1924 	} else {
1925 		info->signals &= ~SerialSignal_DSR;
1926 		info->input_signal_events.dsr_down++;
1927 	}
1928 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1929 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1930 		slgt_irq_off(info, IRQ_DSR);
1931 		return;
1932 	}
1933 	info->icount.dsr++;
1934 	wake_up_interruptible(&info->status_event_wait_q);
1935 	wake_up_interruptible(&info->event_wait_q);
1936 	info->pending_bh |= BH_STATUS;
1937 }
1938 
1939 static void cts_change(struct slgt_info *info, unsigned short status)
1940 {
1941 	if (status & BIT2) {
1942 		info->signals |= SerialSignal_CTS;
1943 		info->input_signal_events.cts_up++;
1944 	} else {
1945 		info->signals &= ~SerialSignal_CTS;
1946 		info->input_signal_events.cts_down++;
1947 	}
1948 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1949 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1950 		slgt_irq_off(info, IRQ_CTS);
1951 		return;
1952 	}
1953 	info->icount.cts++;
1954 	wake_up_interruptible(&info->status_event_wait_q);
1955 	wake_up_interruptible(&info->event_wait_q);
1956 	info->pending_bh |= BH_STATUS;
1957 
1958 	if (tty_port_cts_enabled(&info->port)) {
1959 		if (info->port.tty) {
1960 			if (info->port.tty->hw_stopped) {
1961 				if (info->signals & SerialSignal_CTS) {
1962 		 			info->port.tty->hw_stopped = 0;
1963 					info->pending_bh |= BH_TRANSMIT;
1964 					return;
1965 				}
1966 			} else {
1967 				if (!(info->signals & SerialSignal_CTS))
1968 		 			info->port.tty->hw_stopped = 1;
1969 			}
1970 		}
1971 	}
1972 }
1973 
1974 static void dcd_change(struct slgt_info *info, unsigned short status)
1975 {
1976 	if (status & BIT1) {
1977 		info->signals |= SerialSignal_DCD;
1978 		info->input_signal_events.dcd_up++;
1979 	} else {
1980 		info->signals &= ~SerialSignal_DCD;
1981 		info->input_signal_events.dcd_down++;
1982 	}
1983 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1984 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1985 		slgt_irq_off(info, IRQ_DCD);
1986 		return;
1987 	}
1988 	info->icount.dcd++;
1989 #if SYNCLINK_GENERIC_HDLC
1990 	if (info->netcount) {
1991 		if (info->signals & SerialSignal_DCD)
1992 			netif_carrier_on(info->netdev);
1993 		else
1994 			netif_carrier_off(info->netdev);
1995 	}
1996 #endif
1997 	wake_up_interruptible(&info->status_event_wait_q);
1998 	wake_up_interruptible(&info->event_wait_q);
1999 	info->pending_bh |= BH_STATUS;
2000 
2001 	if (tty_port_check_carrier(&info->port)) {
2002 		if (info->signals & SerialSignal_DCD)
2003 			wake_up_interruptible(&info->port.open_wait);
2004 		else {
2005 			if (info->port.tty)
2006 				tty_hangup(info->port.tty);
2007 		}
2008 	}
2009 }
2010 
2011 static void ri_change(struct slgt_info *info, unsigned short status)
2012 {
2013 	if (status & BIT0) {
2014 		info->signals |= SerialSignal_RI;
2015 		info->input_signal_events.ri_up++;
2016 	} else {
2017 		info->signals &= ~SerialSignal_RI;
2018 		info->input_signal_events.ri_down++;
2019 	}
2020 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2021 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2022 		slgt_irq_off(info, IRQ_RI);
2023 		return;
2024 	}
2025 	info->icount.rng++;
2026 	wake_up_interruptible(&info->status_event_wait_q);
2027 	wake_up_interruptible(&info->event_wait_q);
2028 	info->pending_bh |= BH_STATUS;
2029 }
2030 
2031 static void isr_rxdata(struct slgt_info *info)
2032 {
2033 	unsigned int count = info->rbuf_fill_count;
2034 	unsigned int i = info->rbuf_fill_index;
2035 	unsigned short reg;
2036 
2037 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2038 		reg = rd_reg16(info, RDR);
2039 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2040 		if (desc_complete(info->rbufs[i])) {
2041 			/* all buffers full */
2042 			rx_stop(info);
2043 			info->rx_restart = true;
2044 			continue;
2045 		}
2046 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2047 		/* async mode saves status byte to buffer for each data byte */
2048 		if (info->params.mode == MGSL_MODE_ASYNC)
2049 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2050 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2051 			/* buffer full or end of frame */
2052 			set_desc_count(info->rbufs[i], count);
2053 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2054 			info->rbuf_fill_count = count = 0;
2055 			if (++i == info->rbuf_count)
2056 				i = 0;
2057 			info->pending_bh |= BH_RECEIVE;
2058 		}
2059 	}
2060 
2061 	info->rbuf_fill_index = i;
2062 	info->rbuf_fill_count = count;
2063 }
2064 
2065 static void isr_serial(struct slgt_info *info)
2066 {
2067 	unsigned short status = rd_reg16(info, SSR);
2068 
2069 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2070 
2071 	wr_reg16(info, SSR, status); /* clear pending */
2072 
2073 	info->irq_occurred = true;
2074 
2075 	if (info->params.mode == MGSL_MODE_ASYNC) {
2076 		if (status & IRQ_TXIDLE) {
2077 			if (info->tx_active)
2078 				isr_txeom(info, status);
2079 		}
2080 		if (info->rx_pio && (status & IRQ_RXDATA))
2081 			isr_rxdata(info);
2082 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2083 			info->icount.brk++;
2084 			/* process break detection if tty control allows */
2085 			if (info->port.tty) {
2086 				if (!(status & info->ignore_status_mask)) {
2087 					if (info->read_status_mask & MASK_BREAK) {
2088 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2089 						if (info->port.flags & ASYNC_SAK)
2090 							do_SAK(info->port.tty);
2091 					}
2092 				}
2093 			}
2094 		}
2095 	} else {
2096 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2097 			isr_txeom(info, status);
2098 		if (info->rx_pio && (status & IRQ_RXDATA))
2099 			isr_rxdata(info);
2100 		if (status & IRQ_RXIDLE) {
2101 			if (status & RXIDLE)
2102 				info->icount.rxidle++;
2103 			else
2104 				info->icount.exithunt++;
2105 			wake_up_interruptible(&info->event_wait_q);
2106 		}
2107 
2108 		if (status & IRQ_RXOVER)
2109 			rx_start(info);
2110 	}
2111 
2112 	if (status & IRQ_DSR)
2113 		dsr_change(info, status);
2114 	if (status & IRQ_CTS)
2115 		cts_change(info, status);
2116 	if (status & IRQ_DCD)
2117 		dcd_change(info, status);
2118 	if (status & IRQ_RI)
2119 		ri_change(info, status);
2120 }
2121 
2122 static void isr_rdma(struct slgt_info *info)
2123 {
2124 	unsigned int status = rd_reg32(info, RDCSR);
2125 
2126 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2127 
2128 	/* RDCSR (rx DMA control/status)
2129 	 *
2130 	 * 31..07  reserved
2131 	 * 06      save status byte to DMA buffer
2132 	 * 05      error
2133 	 * 04      eol (end of list)
2134 	 * 03      eob (end of buffer)
2135 	 * 02      IRQ enable
2136 	 * 01      reset
2137 	 * 00      enable
2138 	 */
2139 	wr_reg32(info, RDCSR, status);	/* clear pending */
2140 
2141 	if (status & (BIT5 + BIT4)) {
2142 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2143 		info->rx_restart = true;
2144 	}
2145 	info->pending_bh |= BH_RECEIVE;
2146 }
2147 
2148 static void isr_tdma(struct slgt_info *info)
2149 {
2150 	unsigned int status = rd_reg32(info, TDCSR);
2151 
2152 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2153 
2154 	/* TDCSR (tx DMA control/status)
2155 	 *
2156 	 * 31..06  reserved
2157 	 * 05      error
2158 	 * 04      eol (end of list)
2159 	 * 03      eob (end of buffer)
2160 	 * 02      IRQ enable
2161 	 * 01      reset
2162 	 * 00      enable
2163 	 */
2164 	wr_reg32(info, TDCSR, status);	/* clear pending */
2165 
2166 	if (status & (BIT5 + BIT4 + BIT3)) {
2167 		// another transmit buffer has completed
2168 		// run bottom half to get more send data from user
2169 		info->pending_bh |= BH_TRANSMIT;
2170 	}
2171 }
2172 
2173 /*
2174  * return true if there are unsent tx DMA buffers, otherwise false
2175  *
2176  * if there are unsent buffers then info->tbuf_start
2177  * is set to index of first unsent buffer
2178  */
2179 static bool unsent_tbufs(struct slgt_info *info)
2180 {
2181 	unsigned int i = info->tbuf_current;
2182 	bool rc = false;
2183 
2184 	/*
2185 	 * search backwards from last loaded buffer (precedes tbuf_current)
2186 	 * for first unsent buffer (desc_count > 0)
2187 	 */
2188 
2189 	do {
2190 		if (i)
2191 			i--;
2192 		else
2193 			i = info->tbuf_count - 1;
2194 		if (!desc_count(info->tbufs[i]))
2195 			break;
2196 		info->tbuf_start = i;
2197 		rc = true;
2198 	} while (i != info->tbuf_current);
2199 
2200 	return rc;
2201 }
2202 
2203 static void isr_txeom(struct slgt_info *info, unsigned short status)
2204 {
2205 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2206 
2207 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2208 	tdma_reset(info);
2209 	if (status & IRQ_TXUNDER) {
2210 		unsigned short val = rd_reg16(info, TCR);
2211 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2212 		wr_reg16(info, TCR, val); /* clear reset bit */
2213 	}
2214 
2215 	if (info->tx_active) {
2216 		if (info->params.mode != MGSL_MODE_ASYNC) {
2217 			if (status & IRQ_TXUNDER)
2218 				info->icount.txunder++;
2219 			else if (status & IRQ_TXIDLE)
2220 				info->icount.txok++;
2221 		}
2222 
2223 		if (unsent_tbufs(info)) {
2224 			tx_start(info);
2225 			update_tx_timer(info);
2226 			return;
2227 		}
2228 		info->tx_active = false;
2229 
2230 		del_timer(&info->tx_timer);
2231 
2232 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2233 			info->signals &= ~SerialSignal_RTS;
2234 			info->drop_rts_on_tx_done = false;
2235 			set_signals(info);
2236 		}
2237 
2238 #if SYNCLINK_GENERIC_HDLC
2239 		if (info->netcount)
2240 			hdlcdev_tx_done(info);
2241 		else
2242 #endif
2243 		{
2244 			if (info->port.tty && (info->port.tty->flow.stopped || info->port.tty->hw_stopped)) {
2245 				tx_stop(info);
2246 				return;
2247 			}
2248 			info->pending_bh |= BH_TRANSMIT;
2249 		}
2250 	}
2251 }
2252 
2253 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2254 {
2255 	struct cond_wait *w, *prev;
2256 
2257 	/* wake processes waiting for specific transitions */
2258 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2259 		if (w->data & changed) {
2260 			w->data = state;
2261 			wake_up_interruptible(&w->q);
2262 			if (prev != NULL)
2263 				prev->next = w->next;
2264 			else
2265 				info->gpio_wait_q = w->next;
2266 		} else
2267 			prev = w;
2268 	}
2269 }
2270 
2271 /* interrupt service routine
2272  *
2273  * 	irq	interrupt number
2274  * 	dev_id	device ID supplied during interrupt registration
2275  */
2276 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2277 {
2278 	struct slgt_info *info = dev_id;
2279 	unsigned int gsr;
2280 	unsigned int i;
2281 
2282 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2283 
2284 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2285 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2286 		info->irq_occurred = true;
2287 		for(i=0; i < info->port_count ; i++) {
2288 			if (info->port_array[i] == NULL)
2289 				continue;
2290 			spin_lock(&info->port_array[i]->lock);
2291 			if (gsr & (BIT8 << i))
2292 				isr_serial(info->port_array[i]);
2293 			if (gsr & (BIT16 << (i*2)))
2294 				isr_rdma(info->port_array[i]);
2295 			if (gsr & (BIT17 << (i*2)))
2296 				isr_tdma(info->port_array[i]);
2297 			spin_unlock(&info->port_array[i]->lock);
2298 		}
2299 	}
2300 
2301 	if (info->gpio_present) {
2302 		unsigned int state;
2303 		unsigned int changed;
2304 		spin_lock(&info->lock);
2305 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2306 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2307 			/* read latched state of GPIO signals */
2308 			state = rd_reg32(info, IOVR);
2309 			/* clear pending GPIO interrupt bits */
2310 			wr_reg32(info, IOSR, changed);
2311 			for (i=0 ; i < info->port_count ; i++) {
2312 				if (info->port_array[i] != NULL)
2313 					isr_gpio(info->port_array[i], changed, state);
2314 			}
2315 		}
2316 		spin_unlock(&info->lock);
2317 	}
2318 
2319 	for(i=0; i < info->port_count ; i++) {
2320 		struct slgt_info *port = info->port_array[i];
2321 		if (port == NULL)
2322 			continue;
2323 		spin_lock(&port->lock);
2324 		if ((port->port.count || port->netcount) &&
2325 		    port->pending_bh && !port->bh_running &&
2326 		    !port->bh_requested) {
2327 			DBGISR(("%s bh queued\n", port->device_name));
2328 			schedule_work(&port->task);
2329 			port->bh_requested = true;
2330 		}
2331 		spin_unlock(&port->lock);
2332 	}
2333 
2334 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2335 	return IRQ_HANDLED;
2336 }
2337 
2338 static int startup(struct slgt_info *info)
2339 {
2340 	DBGINFO(("%s startup\n", info->device_name));
2341 
2342 	if (tty_port_initialized(&info->port))
2343 		return 0;
2344 
2345 	if (!info->tx_buf) {
2346 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2347 		if (!info->tx_buf) {
2348 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2349 			return -ENOMEM;
2350 		}
2351 	}
2352 
2353 	info->pending_bh = 0;
2354 
2355 	memset(&info->icount, 0, sizeof(info->icount));
2356 
2357 	/* program hardware for current parameters */
2358 	change_params(info);
2359 
2360 	if (info->port.tty)
2361 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2362 
2363 	tty_port_set_initialized(&info->port, 1);
2364 
2365 	return 0;
2366 }
2367 
2368 /*
2369  *  called by close() and hangup() to shutdown hardware
2370  */
2371 static void shutdown(struct slgt_info *info)
2372 {
2373 	unsigned long flags;
2374 
2375 	if (!tty_port_initialized(&info->port))
2376 		return;
2377 
2378 	DBGINFO(("%s shutdown\n", info->device_name));
2379 
2380 	/* clear status wait queue because status changes */
2381 	/* can't happen after shutting down the hardware */
2382 	wake_up_interruptible(&info->status_event_wait_q);
2383 	wake_up_interruptible(&info->event_wait_q);
2384 
2385 	del_timer_sync(&info->tx_timer);
2386 	del_timer_sync(&info->rx_timer);
2387 
2388 	kfree(info->tx_buf);
2389 	info->tx_buf = NULL;
2390 
2391 	spin_lock_irqsave(&info->lock,flags);
2392 
2393 	tx_stop(info);
2394 	rx_stop(info);
2395 
2396 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2397 
2398  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2399 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2400 		set_signals(info);
2401 	}
2402 
2403 	flush_cond_wait(&info->gpio_wait_q);
2404 
2405 	spin_unlock_irqrestore(&info->lock,flags);
2406 
2407 	if (info->port.tty)
2408 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2409 
2410 	tty_port_set_initialized(&info->port, 0);
2411 }
2412 
2413 static void program_hw(struct slgt_info *info)
2414 {
2415 	unsigned long flags;
2416 
2417 	spin_lock_irqsave(&info->lock,flags);
2418 
2419 	rx_stop(info);
2420 	tx_stop(info);
2421 
2422 	if (info->params.mode != MGSL_MODE_ASYNC ||
2423 	    info->netcount)
2424 		sync_mode(info);
2425 	else
2426 		async_mode(info);
2427 
2428 	set_signals(info);
2429 
2430 	info->dcd_chkcount = 0;
2431 	info->cts_chkcount = 0;
2432 	info->ri_chkcount = 0;
2433 	info->dsr_chkcount = 0;
2434 
2435 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2436 	get_signals(info);
2437 
2438 	if (info->netcount ||
2439 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2440 		rx_start(info);
2441 
2442 	spin_unlock_irqrestore(&info->lock,flags);
2443 }
2444 
2445 /*
2446  * reconfigure adapter based on new parameters
2447  */
2448 static void change_params(struct slgt_info *info)
2449 {
2450 	unsigned cflag;
2451 	int bits_per_char;
2452 
2453 	if (!info->port.tty)
2454 		return;
2455 	DBGINFO(("%s change_params\n", info->device_name));
2456 
2457 	cflag = info->port.tty->termios.c_cflag;
2458 
2459 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2460 	/* otherwise assert RTS and DTR */
2461  	if (cflag & CBAUD)
2462 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2463 	else
2464 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2465 
2466 	/* byte size and parity */
2467 
2468 	info->params.data_bits = tty_get_char_size(cflag);
2469 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2470 
2471 	if (cflag & PARENB)
2472 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2473 	else
2474 		info->params.parity = ASYNC_PARITY_NONE;
2475 
2476 	/* calculate number of jiffies to transmit a full
2477 	 * FIFO (32 bytes) at specified data rate
2478 	 */
2479 	bits_per_char = info->params.data_bits +
2480 			info->params.stop_bits + 1;
2481 
2482 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2483 
2484 	if (info->params.data_rate) {
2485 		info->timeout = (32*HZ*bits_per_char) /
2486 				info->params.data_rate;
2487 	}
2488 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2489 
2490 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2491 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2492 
2493 	/* process tty input control flags */
2494 
2495 	info->read_status_mask = IRQ_RXOVER;
2496 	if (I_INPCK(info->port.tty))
2497 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2498 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2499 		info->read_status_mask |= MASK_BREAK;
2500 	if (I_IGNPAR(info->port.tty))
2501 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2502 	if (I_IGNBRK(info->port.tty)) {
2503 		info->ignore_status_mask |= MASK_BREAK;
2504 		/* If ignoring parity and break indicators, ignore
2505 		 * overruns too.  (For real raw support).
2506 		 */
2507 		if (I_IGNPAR(info->port.tty))
2508 			info->ignore_status_mask |= MASK_OVERRUN;
2509 	}
2510 
2511 	program_hw(info);
2512 }
2513 
2514 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2515 {
2516 	DBGINFO(("%s get_stats\n",  info->device_name));
2517 	if (!user_icount) {
2518 		memset(&info->icount, 0, sizeof(info->icount));
2519 	} else {
2520 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2521 			return -EFAULT;
2522 	}
2523 	return 0;
2524 }
2525 
2526 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2527 {
2528 	DBGINFO(("%s get_params\n", info->device_name));
2529 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2530 		return -EFAULT;
2531 	return 0;
2532 }
2533 
2534 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2535 {
2536  	unsigned long flags;
2537 	MGSL_PARAMS tmp_params;
2538 
2539 	DBGINFO(("%s set_params\n", info->device_name));
2540 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2541 		return -EFAULT;
2542 
2543 	spin_lock_irqsave(&info->lock, flags);
2544 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2545 		info->base_clock = tmp_params.clock_speed;
2546 	else
2547 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2548 	spin_unlock_irqrestore(&info->lock, flags);
2549 
2550 	program_hw(info);
2551 
2552 	return 0;
2553 }
2554 
2555 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2556 {
2557 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2558 	if (put_user(info->idle_mode, idle_mode))
2559 		return -EFAULT;
2560 	return 0;
2561 }
2562 
2563 static int set_txidle(struct slgt_info *info, int idle_mode)
2564 {
2565  	unsigned long flags;
2566 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2567 	spin_lock_irqsave(&info->lock,flags);
2568 	info->idle_mode = idle_mode;
2569 	if (info->params.mode != MGSL_MODE_ASYNC)
2570 		tx_set_idle(info);
2571 	spin_unlock_irqrestore(&info->lock,flags);
2572 	return 0;
2573 }
2574 
2575 static int tx_enable(struct slgt_info *info, int enable)
2576 {
2577  	unsigned long flags;
2578 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2579 	spin_lock_irqsave(&info->lock,flags);
2580 	if (enable) {
2581 		if (!info->tx_enabled)
2582 			tx_start(info);
2583 	} else {
2584 		if (info->tx_enabled)
2585 			tx_stop(info);
2586 	}
2587 	spin_unlock_irqrestore(&info->lock,flags);
2588 	return 0;
2589 }
2590 
2591 /*
2592  * abort transmit HDLC frame
2593  */
2594 static int tx_abort(struct slgt_info *info)
2595 {
2596  	unsigned long flags;
2597 	DBGINFO(("%s tx_abort\n", info->device_name));
2598 	spin_lock_irqsave(&info->lock,flags);
2599 	tdma_reset(info);
2600 	spin_unlock_irqrestore(&info->lock,flags);
2601 	return 0;
2602 }
2603 
2604 static int rx_enable(struct slgt_info *info, int enable)
2605 {
2606  	unsigned long flags;
2607 	unsigned int rbuf_fill_level;
2608 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2609 	spin_lock_irqsave(&info->lock,flags);
2610 	/*
2611 	 * enable[31..16] = receive DMA buffer fill level
2612 	 * 0 = noop (leave fill level unchanged)
2613 	 * fill level must be multiple of 4 and <= buffer size
2614 	 */
2615 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2616 	if (rbuf_fill_level) {
2617 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2618 			spin_unlock_irqrestore(&info->lock, flags);
2619 			return -EINVAL;
2620 		}
2621 		info->rbuf_fill_level = rbuf_fill_level;
2622 		if (rbuf_fill_level < 128)
2623 			info->rx_pio = 1; /* PIO mode */
2624 		else
2625 			info->rx_pio = 0; /* DMA mode */
2626 		rx_stop(info); /* restart receiver to use new fill level */
2627 	}
2628 
2629 	/*
2630 	 * enable[1..0] = receiver enable command
2631 	 * 0 = disable
2632 	 * 1 = enable
2633 	 * 2 = enable or force hunt mode if already enabled
2634 	 */
2635 	enable &= 3;
2636 	if (enable) {
2637 		if (!info->rx_enabled)
2638 			rx_start(info);
2639 		else if (enable == 2) {
2640 			/* force hunt mode (write 1 to RCR[3]) */
2641 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2642 		}
2643 	} else {
2644 		if (info->rx_enabled)
2645 			rx_stop(info);
2646 	}
2647 	spin_unlock_irqrestore(&info->lock,flags);
2648 	return 0;
2649 }
2650 
2651 /*
2652  *  wait for specified event to occur
2653  */
2654 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2655 {
2656  	unsigned long flags;
2657 	int s;
2658 	int rc=0;
2659 	struct mgsl_icount cprev, cnow;
2660 	int events;
2661 	int mask;
2662 	struct	_input_signal_events oldsigs, newsigs;
2663 	DECLARE_WAITQUEUE(wait, current);
2664 
2665 	if (get_user(mask, mask_ptr))
2666 		return -EFAULT;
2667 
2668 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2669 
2670 	spin_lock_irqsave(&info->lock,flags);
2671 
2672 	/* return immediately if state matches requested events */
2673 	get_signals(info);
2674 	s = info->signals;
2675 
2676 	events = mask &
2677 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2678  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2679 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2680 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2681 	if (events) {
2682 		spin_unlock_irqrestore(&info->lock,flags);
2683 		goto exit;
2684 	}
2685 
2686 	/* save current irq counts */
2687 	cprev = info->icount;
2688 	oldsigs = info->input_signal_events;
2689 
2690 	/* enable hunt and idle irqs if needed */
2691 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2692 		unsigned short val = rd_reg16(info, SCR);
2693 		if (!(val & IRQ_RXIDLE))
2694 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2695 	}
2696 
2697 	set_current_state(TASK_INTERRUPTIBLE);
2698 	add_wait_queue(&info->event_wait_q, &wait);
2699 
2700 	spin_unlock_irqrestore(&info->lock,flags);
2701 
2702 	for(;;) {
2703 		schedule();
2704 		if (signal_pending(current)) {
2705 			rc = -ERESTARTSYS;
2706 			break;
2707 		}
2708 
2709 		/* get current irq counts */
2710 		spin_lock_irqsave(&info->lock,flags);
2711 		cnow = info->icount;
2712 		newsigs = info->input_signal_events;
2713 		set_current_state(TASK_INTERRUPTIBLE);
2714 		spin_unlock_irqrestore(&info->lock,flags);
2715 
2716 		/* if no change, wait aborted for some reason */
2717 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2718 		    newsigs.dsr_down == oldsigs.dsr_down &&
2719 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2720 		    newsigs.dcd_down == oldsigs.dcd_down &&
2721 		    newsigs.cts_up   == oldsigs.cts_up   &&
2722 		    newsigs.cts_down == oldsigs.cts_down &&
2723 		    newsigs.ri_up    == oldsigs.ri_up    &&
2724 		    newsigs.ri_down  == oldsigs.ri_down  &&
2725 		    cnow.exithunt    == cprev.exithunt   &&
2726 		    cnow.rxidle      == cprev.rxidle) {
2727 			rc = -EIO;
2728 			break;
2729 		}
2730 
2731 		events = mask &
2732 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2733 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2734 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2735 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2736 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2737 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2738 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2739 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2740 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2741 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2742 		if (events)
2743 			break;
2744 
2745 		cprev = cnow;
2746 		oldsigs = newsigs;
2747 	}
2748 
2749 	remove_wait_queue(&info->event_wait_q, &wait);
2750 	set_current_state(TASK_RUNNING);
2751 
2752 
2753 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2754 		spin_lock_irqsave(&info->lock,flags);
2755 		if (!waitqueue_active(&info->event_wait_q)) {
2756 			/* disable enable exit hunt mode/idle rcvd IRQs */
2757 			wr_reg16(info, SCR,
2758 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2759 		}
2760 		spin_unlock_irqrestore(&info->lock,flags);
2761 	}
2762 exit:
2763 	if (rc == 0)
2764 		rc = put_user(events, mask_ptr);
2765 	return rc;
2766 }
2767 
2768 static int get_interface(struct slgt_info *info, int __user *if_mode)
2769 {
2770 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2771 	if (put_user(info->if_mode, if_mode))
2772 		return -EFAULT;
2773 	return 0;
2774 }
2775 
2776 static int set_interface(struct slgt_info *info, int if_mode)
2777 {
2778  	unsigned long flags;
2779 	unsigned short val;
2780 
2781 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2782 	spin_lock_irqsave(&info->lock,flags);
2783 	info->if_mode = if_mode;
2784 
2785 	msc_set_vcr(info);
2786 
2787 	/* TCR (tx control) 07  1=RTS driver control */
2788 	val = rd_reg16(info, TCR);
2789 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2790 		val |= BIT7;
2791 	else
2792 		val &= ~BIT7;
2793 	wr_reg16(info, TCR, val);
2794 
2795 	spin_unlock_irqrestore(&info->lock,flags);
2796 	return 0;
2797 }
2798 
2799 static int get_xsync(struct slgt_info *info, int __user *xsync)
2800 {
2801 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2802 	if (put_user(info->xsync, xsync))
2803 		return -EFAULT;
2804 	return 0;
2805 }
2806 
2807 /*
2808  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2809  *
2810  * sync pattern is contained in least significant bytes of value
2811  * most significant byte of sync pattern is oldest (1st sent/detected)
2812  */
2813 static int set_xsync(struct slgt_info *info, int xsync)
2814 {
2815 	unsigned long flags;
2816 
2817 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2818 	spin_lock_irqsave(&info->lock, flags);
2819 	info->xsync = xsync;
2820 	wr_reg32(info, XSR, xsync);
2821 	spin_unlock_irqrestore(&info->lock, flags);
2822 	return 0;
2823 }
2824 
2825 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2826 {
2827 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2828 	if (put_user(info->xctrl, xctrl))
2829 		return -EFAULT;
2830 	return 0;
2831 }
2832 
2833 /*
2834  * set extended control options
2835  *
2836  * xctrl[31:19] reserved, must be zero
2837  * xctrl[18:17] extended sync pattern length in bytes
2838  *              00 = 1 byte  in xsr[7:0]
2839  *              01 = 2 bytes in xsr[15:0]
2840  *              10 = 3 bytes in xsr[23:0]
2841  *              11 = 4 bytes in xsr[31:0]
2842  * xctrl[16]    1 = enable terminal count, 0=disabled
2843  * xctrl[15:0]  receive terminal count for fixed length packets
2844  *              value is count minus one (0 = 1 byte packet)
2845  *              when terminal count is reached, receiver
2846  *              automatically returns to hunt mode and receive
2847  *              FIFO contents are flushed to DMA buffers with
2848  *              end of frame (EOF) status
2849  */
2850 static int set_xctrl(struct slgt_info *info, int xctrl)
2851 {
2852 	unsigned long flags;
2853 
2854 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2855 	spin_lock_irqsave(&info->lock, flags);
2856 	info->xctrl = xctrl;
2857 	wr_reg32(info, XCR, xctrl);
2858 	spin_unlock_irqrestore(&info->lock, flags);
2859 	return 0;
2860 }
2861 
2862 /*
2863  * set general purpose IO pin state and direction
2864  *
2865  * user_gpio fields:
2866  * state   each bit indicates a pin state
2867  * smask   set bit indicates pin state to set
2868  * dir     each bit indicates a pin direction (0=input, 1=output)
2869  * dmask   set bit indicates pin direction to set
2870  */
2871 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2872 {
2873  	unsigned long flags;
2874 	struct gpio_desc gpio;
2875 	__u32 data;
2876 
2877 	if (!info->gpio_present)
2878 		return -EINVAL;
2879 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2880 		return -EFAULT;
2881 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2882 		 info->device_name, gpio.state, gpio.smask,
2883 		 gpio.dir, gpio.dmask));
2884 
2885 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2886 	if (gpio.dmask) {
2887 		data = rd_reg32(info, IODR);
2888 		data |= gpio.dmask & gpio.dir;
2889 		data &= ~(gpio.dmask & ~gpio.dir);
2890 		wr_reg32(info, IODR, data);
2891 	}
2892 	if (gpio.smask) {
2893 		data = rd_reg32(info, IOVR);
2894 		data |= gpio.smask & gpio.state;
2895 		data &= ~(gpio.smask & ~gpio.state);
2896 		wr_reg32(info, IOVR, data);
2897 	}
2898 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2899 
2900 	return 0;
2901 }
2902 
2903 /*
2904  * get general purpose IO pin state and direction
2905  */
2906 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2907 {
2908 	struct gpio_desc gpio;
2909 	if (!info->gpio_present)
2910 		return -EINVAL;
2911 	gpio.state = rd_reg32(info, IOVR);
2912 	gpio.smask = 0xffffffff;
2913 	gpio.dir   = rd_reg32(info, IODR);
2914 	gpio.dmask = 0xffffffff;
2915 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2916 		return -EFAULT;
2917 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2918 		 info->device_name, gpio.state, gpio.dir));
2919 	return 0;
2920 }
2921 
2922 /*
2923  * conditional wait facility
2924  */
2925 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2926 {
2927 	init_waitqueue_head(&w->q);
2928 	init_waitqueue_entry(&w->wait, current);
2929 	w->data = data;
2930 }
2931 
2932 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2933 {
2934 	set_current_state(TASK_INTERRUPTIBLE);
2935 	add_wait_queue(&w->q, &w->wait);
2936 	w->next = *head;
2937 	*head = w;
2938 }
2939 
2940 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2941 {
2942 	struct cond_wait *w, *prev;
2943 	remove_wait_queue(&cw->q, &cw->wait);
2944 	set_current_state(TASK_RUNNING);
2945 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2946 		if (w == cw) {
2947 			if (prev != NULL)
2948 				prev->next = w->next;
2949 			else
2950 				*head = w->next;
2951 			break;
2952 		}
2953 	}
2954 }
2955 
2956 static void flush_cond_wait(struct cond_wait **head)
2957 {
2958 	while (*head != NULL) {
2959 		wake_up_interruptible(&(*head)->q);
2960 		*head = (*head)->next;
2961 	}
2962 }
2963 
2964 /*
2965  * wait for general purpose I/O pin(s) to enter specified state
2966  *
2967  * user_gpio fields:
2968  * state - bit indicates target pin state
2969  * smask - set bit indicates watched pin
2970  *
2971  * The wait ends when at least one watched pin enters the specified
2972  * state. When 0 (no error) is returned, user_gpio->state is set to the
2973  * state of all GPIO pins when the wait ends.
2974  *
2975  * Note: Each pin may be a dedicated input, dedicated output, or
2976  * configurable input/output. The number and configuration of pins
2977  * varies with the specific adapter model. Only input pins (dedicated
2978  * or configured) can be monitored with this function.
2979  */
2980 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2981 {
2982  	unsigned long flags;
2983 	int rc = 0;
2984 	struct gpio_desc gpio;
2985 	struct cond_wait wait;
2986 	u32 state;
2987 
2988 	if (!info->gpio_present)
2989 		return -EINVAL;
2990 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2991 		return -EFAULT;
2992 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
2993 		 info->device_name, gpio.state, gpio.smask));
2994 	/* ignore output pins identified by set IODR bit */
2995 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
2996 		return -EINVAL;
2997 	init_cond_wait(&wait, gpio.smask);
2998 
2999 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3000 	/* enable interrupts for watched pins */
3001 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3002 	/* get current pin states */
3003 	state = rd_reg32(info, IOVR);
3004 
3005 	if (gpio.smask & ~(state ^ gpio.state)) {
3006 		/* already in target state */
3007 		gpio.state = state;
3008 	} else {
3009 		/* wait for target state */
3010 		add_cond_wait(&info->gpio_wait_q, &wait);
3011 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3012 		schedule();
3013 		if (signal_pending(current))
3014 			rc = -ERESTARTSYS;
3015 		else
3016 			gpio.state = wait.data;
3017 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3018 		remove_cond_wait(&info->gpio_wait_q, &wait);
3019 	}
3020 
3021 	/* disable all GPIO interrupts if no waiting processes */
3022 	if (info->gpio_wait_q == NULL)
3023 		wr_reg32(info, IOER, 0);
3024 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3025 
3026 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3027 		rc = -EFAULT;
3028 	return rc;
3029 }
3030 
3031 static int modem_input_wait(struct slgt_info *info,int arg)
3032 {
3033  	unsigned long flags;
3034 	int rc;
3035 	struct mgsl_icount cprev, cnow;
3036 	DECLARE_WAITQUEUE(wait, current);
3037 
3038 	/* save current irq counts */
3039 	spin_lock_irqsave(&info->lock,flags);
3040 	cprev = info->icount;
3041 	add_wait_queue(&info->status_event_wait_q, &wait);
3042 	set_current_state(TASK_INTERRUPTIBLE);
3043 	spin_unlock_irqrestore(&info->lock,flags);
3044 
3045 	for(;;) {
3046 		schedule();
3047 		if (signal_pending(current)) {
3048 			rc = -ERESTARTSYS;
3049 			break;
3050 		}
3051 
3052 		/* get new irq counts */
3053 		spin_lock_irqsave(&info->lock,flags);
3054 		cnow = info->icount;
3055 		set_current_state(TASK_INTERRUPTIBLE);
3056 		spin_unlock_irqrestore(&info->lock,flags);
3057 
3058 		/* if no change, wait aborted for some reason */
3059 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3060 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3061 			rc = -EIO;
3062 			break;
3063 		}
3064 
3065 		/* check for change in caller specified modem input */
3066 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3067 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3068 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3069 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3070 			rc = 0;
3071 			break;
3072 		}
3073 
3074 		cprev = cnow;
3075 	}
3076 	remove_wait_queue(&info->status_event_wait_q, &wait);
3077 	set_current_state(TASK_RUNNING);
3078 	return rc;
3079 }
3080 
3081 /*
3082  *  return state of serial control and status signals
3083  */
3084 static int tiocmget(struct tty_struct *tty)
3085 {
3086 	struct slgt_info *info = tty->driver_data;
3087 	unsigned int result;
3088  	unsigned long flags;
3089 
3090 	spin_lock_irqsave(&info->lock,flags);
3091  	get_signals(info);
3092 	spin_unlock_irqrestore(&info->lock,flags);
3093 
3094 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3095 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3096 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3097 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3098 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3099 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3100 
3101 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3102 	return result;
3103 }
3104 
3105 /*
3106  * set modem control signals (DTR/RTS)
3107  *
3108  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3109  *		TIOCMSET = set/clear signal values
3110  * 	value	bit mask for command
3111  */
3112 static int tiocmset(struct tty_struct *tty,
3113 		    unsigned int set, unsigned int clear)
3114 {
3115 	struct slgt_info *info = tty->driver_data;
3116  	unsigned long flags;
3117 
3118 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3119 
3120 	if (set & TIOCM_RTS)
3121 		info->signals |= SerialSignal_RTS;
3122 	if (set & TIOCM_DTR)
3123 		info->signals |= SerialSignal_DTR;
3124 	if (clear & TIOCM_RTS)
3125 		info->signals &= ~SerialSignal_RTS;
3126 	if (clear & TIOCM_DTR)
3127 		info->signals &= ~SerialSignal_DTR;
3128 
3129 	spin_lock_irqsave(&info->lock,flags);
3130 	set_signals(info);
3131 	spin_unlock_irqrestore(&info->lock,flags);
3132 	return 0;
3133 }
3134 
3135 static int carrier_raised(struct tty_port *port)
3136 {
3137 	unsigned long flags;
3138 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3139 
3140 	spin_lock_irqsave(&info->lock,flags);
3141 	get_signals(info);
3142 	spin_unlock_irqrestore(&info->lock,flags);
3143 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3144 }
3145 
3146 static void dtr_rts(struct tty_port *port, int on)
3147 {
3148 	unsigned long flags;
3149 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3150 
3151 	spin_lock_irqsave(&info->lock,flags);
3152 	if (on)
3153 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3154 	else
3155 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3156 	set_signals(info);
3157 	spin_unlock_irqrestore(&info->lock,flags);
3158 }
3159 
3160 
3161 /*
3162  *  block current process until the device is ready to open
3163  */
3164 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3165 			   struct slgt_info *info)
3166 {
3167 	DECLARE_WAITQUEUE(wait, current);
3168 	int		retval;
3169 	bool		do_clocal = false;
3170 	unsigned long	flags;
3171 	int		cd;
3172 	struct tty_port *port = &info->port;
3173 
3174 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3175 
3176 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3177 		/* nonblock mode is set or port is not enabled */
3178 		tty_port_set_active(port, 1);
3179 		return 0;
3180 	}
3181 
3182 	if (C_CLOCAL(tty))
3183 		do_clocal = true;
3184 
3185 	/* Wait for carrier detect and the line to become
3186 	 * free (i.e., not in use by the callout).  While we are in
3187 	 * this loop, port->count is dropped by one, so that
3188 	 * close() knows when to free things.  We restore it upon
3189 	 * exit, either normal or abnormal.
3190 	 */
3191 
3192 	retval = 0;
3193 	add_wait_queue(&port->open_wait, &wait);
3194 
3195 	spin_lock_irqsave(&info->lock, flags);
3196 	port->count--;
3197 	spin_unlock_irqrestore(&info->lock, flags);
3198 	port->blocked_open++;
3199 
3200 	while (1) {
3201 		if (C_BAUD(tty) && tty_port_initialized(port))
3202 			tty_port_raise_dtr_rts(port);
3203 
3204 		set_current_state(TASK_INTERRUPTIBLE);
3205 
3206 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3207 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3208 					-EAGAIN : -ERESTARTSYS;
3209 			break;
3210 		}
3211 
3212 		cd = tty_port_carrier_raised(port);
3213 		if (do_clocal || cd)
3214 			break;
3215 
3216 		if (signal_pending(current)) {
3217 			retval = -ERESTARTSYS;
3218 			break;
3219 		}
3220 
3221 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3222 		tty_unlock(tty);
3223 		schedule();
3224 		tty_lock(tty);
3225 	}
3226 
3227 	set_current_state(TASK_RUNNING);
3228 	remove_wait_queue(&port->open_wait, &wait);
3229 
3230 	if (!tty_hung_up_p(filp))
3231 		port->count++;
3232 	port->blocked_open--;
3233 
3234 	if (!retval)
3235 		tty_port_set_active(port, 1);
3236 
3237 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3238 	return retval;
3239 }
3240 
3241 /*
3242  * allocate buffers used for calling line discipline receive_buf
3243  * directly in synchronous mode
3244  * note: add 5 bytes to max frame size to allow appending
3245  * 32-bit CRC and status byte when configured to do so
3246  */
3247 static int alloc_tmp_rbuf(struct slgt_info *info)
3248 {
3249 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3250 	if (info->tmp_rbuf == NULL)
3251 		return -ENOMEM;
3252 	/* unused flag buffer to satisfy receive_buf calling interface */
3253 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3254 	if (!info->flag_buf) {
3255 		kfree(info->tmp_rbuf);
3256 		info->tmp_rbuf = NULL;
3257 		return -ENOMEM;
3258 	}
3259 	return 0;
3260 }
3261 
3262 static void free_tmp_rbuf(struct slgt_info *info)
3263 {
3264 	kfree(info->tmp_rbuf);
3265 	info->tmp_rbuf = NULL;
3266 	kfree(info->flag_buf);
3267 	info->flag_buf = NULL;
3268 }
3269 
3270 /*
3271  * allocate DMA descriptor lists.
3272  */
3273 static int alloc_desc(struct slgt_info *info)
3274 {
3275 	unsigned int i;
3276 	unsigned int pbufs;
3277 
3278 	/* allocate memory to hold descriptor lists */
3279 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3280 					&info->bufs_dma_addr, GFP_KERNEL);
3281 	if (info->bufs == NULL)
3282 		return -ENOMEM;
3283 
3284 	info->rbufs = (struct slgt_desc*)info->bufs;
3285 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3286 
3287 	pbufs = (unsigned int)info->bufs_dma_addr;
3288 
3289 	/*
3290 	 * Build circular lists of descriptors
3291 	 */
3292 
3293 	for (i=0; i < info->rbuf_count; i++) {
3294 		/* physical address of this descriptor */
3295 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3296 
3297 		/* physical address of next descriptor */
3298 		if (i == info->rbuf_count - 1)
3299 			info->rbufs[i].next = cpu_to_le32(pbufs);
3300 		else
3301 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3302 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3303 	}
3304 
3305 	for (i=0; i < info->tbuf_count; i++) {
3306 		/* physical address of this descriptor */
3307 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3308 
3309 		/* physical address of next descriptor */
3310 		if (i == info->tbuf_count - 1)
3311 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3312 		else
3313 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3314 	}
3315 
3316 	return 0;
3317 }
3318 
3319 static void free_desc(struct slgt_info *info)
3320 {
3321 	if (info->bufs != NULL) {
3322 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3323 				  info->bufs, info->bufs_dma_addr);
3324 		info->bufs  = NULL;
3325 		info->rbufs = NULL;
3326 		info->tbufs = NULL;
3327 	}
3328 }
3329 
3330 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3331 {
3332 	int i;
3333 	for (i=0; i < count; i++) {
3334 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3335 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3336 		if (!bufs[i].buf)
3337 			return -ENOMEM;
3338 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3339 	}
3340 	return 0;
3341 }
3342 
3343 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3344 {
3345 	int i;
3346 	for (i=0; i < count; i++) {
3347 		if (bufs[i].buf == NULL)
3348 			continue;
3349 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3350 				  bufs[i].buf_dma_addr);
3351 		bufs[i].buf = NULL;
3352 	}
3353 }
3354 
3355 static int alloc_dma_bufs(struct slgt_info *info)
3356 {
3357 	info->rbuf_count = 32;
3358 	info->tbuf_count = 32;
3359 
3360 	if (alloc_desc(info) < 0 ||
3361 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3362 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3363 	    alloc_tmp_rbuf(info) < 0) {
3364 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3365 		return -ENOMEM;
3366 	}
3367 	reset_rbufs(info);
3368 	return 0;
3369 }
3370 
3371 static void free_dma_bufs(struct slgt_info *info)
3372 {
3373 	if (info->bufs) {
3374 		free_bufs(info, info->rbufs, info->rbuf_count);
3375 		free_bufs(info, info->tbufs, info->tbuf_count);
3376 		free_desc(info);
3377 	}
3378 	free_tmp_rbuf(info);
3379 }
3380 
3381 static int claim_resources(struct slgt_info *info)
3382 {
3383 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3384 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3385 			info->device_name, info->phys_reg_addr));
3386 		info->init_error = DiagStatus_AddressConflict;
3387 		goto errout;
3388 	}
3389 	else
3390 		info->reg_addr_requested = true;
3391 
3392 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3393 	if (!info->reg_addr) {
3394 		DBGERR(("%s can't map device registers, addr=%08X\n",
3395 			info->device_name, info->phys_reg_addr));
3396 		info->init_error = DiagStatus_CantAssignPciResources;
3397 		goto errout;
3398 	}
3399 	return 0;
3400 
3401 errout:
3402 	release_resources(info);
3403 	return -ENODEV;
3404 }
3405 
3406 static void release_resources(struct slgt_info *info)
3407 {
3408 	if (info->irq_requested) {
3409 		free_irq(info->irq_level, info);
3410 		info->irq_requested = false;
3411 	}
3412 
3413 	if (info->reg_addr_requested) {
3414 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3415 		info->reg_addr_requested = false;
3416 	}
3417 
3418 	if (info->reg_addr) {
3419 		iounmap(info->reg_addr);
3420 		info->reg_addr = NULL;
3421 	}
3422 }
3423 
3424 /* Add the specified device instance data structure to the
3425  * global linked list of devices and increment the device count.
3426  */
3427 static void add_device(struct slgt_info *info)
3428 {
3429 	char *devstr;
3430 
3431 	info->next_device = NULL;
3432 	info->line = slgt_device_count;
3433 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3434 
3435 	if (info->line < MAX_DEVICES) {
3436 		if (maxframe[info->line])
3437 			info->max_frame_size = maxframe[info->line];
3438 	}
3439 
3440 	slgt_device_count++;
3441 
3442 	if (!slgt_device_list)
3443 		slgt_device_list = info;
3444 	else {
3445 		struct slgt_info *current_dev = slgt_device_list;
3446 		while(current_dev->next_device)
3447 			current_dev = current_dev->next_device;
3448 		current_dev->next_device = info;
3449 	}
3450 
3451 	if (info->max_frame_size < 4096)
3452 		info->max_frame_size = 4096;
3453 	else if (info->max_frame_size > 65535)
3454 		info->max_frame_size = 65535;
3455 
3456 	switch(info->pdev->device) {
3457 	case SYNCLINK_GT_DEVICE_ID:
3458 		devstr = "GT";
3459 		break;
3460 	case SYNCLINK_GT2_DEVICE_ID:
3461 		devstr = "GT2";
3462 		break;
3463 	case SYNCLINK_GT4_DEVICE_ID:
3464 		devstr = "GT4";
3465 		break;
3466 	case SYNCLINK_AC_DEVICE_ID:
3467 		devstr = "AC";
3468 		info->params.mode = MGSL_MODE_ASYNC;
3469 		break;
3470 	default:
3471 		devstr = "(unknown model)";
3472 	}
3473 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3474 		devstr, info->device_name, info->phys_reg_addr,
3475 		info->irq_level, info->max_frame_size);
3476 
3477 #if SYNCLINK_GENERIC_HDLC
3478 	hdlcdev_init(info);
3479 #endif
3480 }
3481 
3482 static const struct tty_port_operations slgt_port_ops = {
3483 	.carrier_raised = carrier_raised,
3484 	.dtr_rts = dtr_rts,
3485 };
3486 
3487 /*
3488  *  allocate device instance structure, return NULL on failure
3489  */
3490 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3491 {
3492 	struct slgt_info *info;
3493 
3494 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3495 
3496 	if (!info) {
3497 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3498 			driver_name, adapter_num, port_num));
3499 	} else {
3500 		tty_port_init(&info->port);
3501 		info->port.ops = &slgt_port_ops;
3502 		info->magic = MGSL_MAGIC;
3503 		INIT_WORK(&info->task, bh_handler);
3504 		info->max_frame_size = 4096;
3505 		info->base_clock = 14745600;
3506 		info->rbuf_fill_level = DMABUFSIZE;
3507 		init_waitqueue_head(&info->status_event_wait_q);
3508 		init_waitqueue_head(&info->event_wait_q);
3509 		spin_lock_init(&info->netlock);
3510 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3511 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3512 		info->adapter_num = adapter_num;
3513 		info->port_num = port_num;
3514 
3515 		timer_setup(&info->tx_timer, tx_timeout, 0);
3516 		timer_setup(&info->rx_timer, rx_timeout, 0);
3517 
3518 		/* Copy configuration info to device instance data */
3519 		info->pdev = pdev;
3520 		info->irq_level = pdev->irq;
3521 		info->phys_reg_addr = pci_resource_start(pdev,0);
3522 
3523 		info->bus_type = MGSL_BUS_TYPE_PCI;
3524 		info->irq_flags = IRQF_SHARED;
3525 
3526 		info->init_error = -1; /* assume error, set to 0 on successful init */
3527 	}
3528 
3529 	return info;
3530 }
3531 
3532 static void device_init(int adapter_num, struct pci_dev *pdev)
3533 {
3534 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3535 	int i;
3536 	int port_count = 1;
3537 
3538 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3539 		port_count = 2;
3540 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3541 		port_count = 4;
3542 
3543 	/* allocate device instances for all ports */
3544 	for (i=0; i < port_count; ++i) {
3545 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3546 		if (port_array[i] == NULL) {
3547 			for (--i; i >= 0; --i) {
3548 				tty_port_destroy(&port_array[i]->port);
3549 				kfree(port_array[i]);
3550 			}
3551 			return;
3552 		}
3553 	}
3554 
3555 	/* give copy of port_array to all ports and add to device list  */
3556 	for (i=0; i < port_count; ++i) {
3557 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3558 		add_device(port_array[i]);
3559 		port_array[i]->port_count = port_count;
3560 		spin_lock_init(&port_array[i]->lock);
3561 	}
3562 
3563 	/* Allocate and claim adapter resources */
3564 	if (!claim_resources(port_array[0])) {
3565 
3566 		alloc_dma_bufs(port_array[0]);
3567 
3568 		/* copy resource information from first port to others */
3569 		for (i = 1; i < port_count; ++i) {
3570 			port_array[i]->irq_level = port_array[0]->irq_level;
3571 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3572 			alloc_dma_bufs(port_array[i]);
3573 		}
3574 
3575 		if (request_irq(port_array[0]->irq_level,
3576 					slgt_interrupt,
3577 					port_array[0]->irq_flags,
3578 					port_array[0]->device_name,
3579 					port_array[0]) < 0) {
3580 			DBGERR(("%s request_irq failed IRQ=%d\n",
3581 				port_array[0]->device_name,
3582 				port_array[0]->irq_level));
3583 		} else {
3584 			port_array[0]->irq_requested = true;
3585 			adapter_test(port_array[0]);
3586 			for (i=1 ; i < port_count ; i++) {
3587 				port_array[i]->init_error = port_array[0]->init_error;
3588 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3589 			}
3590 		}
3591 	}
3592 
3593 	for (i = 0; i < port_count; ++i) {
3594 		struct slgt_info *info = port_array[i];
3595 		tty_port_register_device(&info->port, serial_driver, info->line,
3596 				&info->pdev->dev);
3597 	}
3598 }
3599 
3600 static int init_one(struct pci_dev *dev,
3601 			      const struct pci_device_id *ent)
3602 {
3603 	if (pci_enable_device(dev)) {
3604 		printk("error enabling pci device %p\n", dev);
3605 		return -EIO;
3606 	}
3607 	pci_set_master(dev);
3608 	device_init(slgt_device_count, dev);
3609 	return 0;
3610 }
3611 
3612 static void remove_one(struct pci_dev *dev)
3613 {
3614 }
3615 
3616 static const struct tty_operations ops = {
3617 	.open = open,
3618 	.close = close,
3619 	.write = write,
3620 	.put_char = put_char,
3621 	.flush_chars = flush_chars,
3622 	.write_room = write_room,
3623 	.chars_in_buffer = chars_in_buffer,
3624 	.flush_buffer = flush_buffer,
3625 	.ioctl = ioctl,
3626 	.compat_ioctl = slgt_compat_ioctl,
3627 	.throttle = throttle,
3628 	.unthrottle = unthrottle,
3629 	.send_xchar = send_xchar,
3630 	.break_ctl = set_break,
3631 	.wait_until_sent = wait_until_sent,
3632 	.set_termios = set_termios,
3633 	.stop = tx_hold,
3634 	.start = tx_release,
3635 	.hangup = hangup,
3636 	.tiocmget = tiocmget,
3637 	.tiocmset = tiocmset,
3638 	.get_icount = get_icount,
3639 	.proc_show = synclink_gt_proc_show,
3640 };
3641 
3642 static void slgt_cleanup(void)
3643 {
3644 	struct slgt_info *info;
3645 	struct slgt_info *tmp;
3646 
3647 	printk(KERN_INFO "unload %s\n", driver_name);
3648 
3649 	if (serial_driver) {
3650 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3651 			tty_unregister_device(serial_driver, info->line);
3652 		tty_unregister_driver(serial_driver);
3653 		put_tty_driver(serial_driver);
3654 	}
3655 
3656 	/* reset devices */
3657 	info = slgt_device_list;
3658 	while(info) {
3659 		reset_port(info);
3660 		info = info->next_device;
3661 	}
3662 
3663 	/* release devices */
3664 	info = slgt_device_list;
3665 	while(info) {
3666 #if SYNCLINK_GENERIC_HDLC
3667 		hdlcdev_exit(info);
3668 #endif
3669 		free_dma_bufs(info);
3670 		free_tmp_rbuf(info);
3671 		if (info->port_num == 0)
3672 			release_resources(info);
3673 		tmp = info;
3674 		info = info->next_device;
3675 		tty_port_destroy(&tmp->port);
3676 		kfree(tmp);
3677 	}
3678 
3679 	if (pci_registered)
3680 		pci_unregister_driver(&pci_driver);
3681 }
3682 
3683 /*
3684  *  Driver initialization entry point.
3685  */
3686 static int __init slgt_init(void)
3687 {
3688 	int rc;
3689 
3690 	printk(KERN_INFO "%s\n", driver_name);
3691 
3692 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3693 	if (!serial_driver) {
3694 		printk("%s can't allocate tty driver\n", driver_name);
3695 		return -ENOMEM;
3696 	}
3697 
3698 	/* Initialize the tty_driver structure */
3699 
3700 	serial_driver->driver_name = slgt_driver_name;
3701 	serial_driver->name = tty_dev_prefix;
3702 	serial_driver->major = ttymajor;
3703 	serial_driver->minor_start = 64;
3704 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3705 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3706 	serial_driver->init_termios = tty_std_termios;
3707 	serial_driver->init_termios.c_cflag =
3708 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3709 	serial_driver->init_termios.c_ispeed = 9600;
3710 	serial_driver->init_termios.c_ospeed = 9600;
3711 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3712 	tty_set_operations(serial_driver, &ops);
3713 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3714 		DBGERR(("%s can't register serial driver\n", driver_name));
3715 		put_tty_driver(serial_driver);
3716 		serial_driver = NULL;
3717 		goto error;
3718 	}
3719 
3720 	printk(KERN_INFO "%s, tty major#%d\n",
3721 	       driver_name, serial_driver->major);
3722 
3723 	slgt_device_count = 0;
3724 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3725 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3726 		goto error;
3727 	}
3728 	pci_registered = true;
3729 
3730 	if (!slgt_device_list)
3731 		printk("%s no devices found\n",driver_name);
3732 
3733 	return 0;
3734 
3735 error:
3736 	slgt_cleanup();
3737 	return rc;
3738 }
3739 
3740 static void __exit slgt_exit(void)
3741 {
3742 	slgt_cleanup();
3743 }
3744 
3745 module_init(slgt_init);
3746 module_exit(slgt_exit);
3747 
3748 /*
3749  * register access routines
3750  */
3751 
3752 #define CALC_REGADDR() \
3753 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3754 	if (addr >= 0x80) \
3755 		reg_addr += (info->port_num) * 32; \
3756 	else if (addr >= 0x40)	\
3757 		reg_addr += (info->port_num) * 16;
3758 
3759 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3760 {
3761 	CALC_REGADDR();
3762 	return readb((void __iomem *)reg_addr);
3763 }
3764 
3765 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3766 {
3767 	CALC_REGADDR();
3768 	writeb(value, (void __iomem *)reg_addr);
3769 }
3770 
3771 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3772 {
3773 	CALC_REGADDR();
3774 	return readw((void __iomem *)reg_addr);
3775 }
3776 
3777 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3778 {
3779 	CALC_REGADDR();
3780 	writew(value, (void __iomem *)reg_addr);
3781 }
3782 
3783 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3784 {
3785 	CALC_REGADDR();
3786 	return readl((void __iomem *)reg_addr);
3787 }
3788 
3789 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3790 {
3791 	CALC_REGADDR();
3792 	writel(value, (void __iomem *)reg_addr);
3793 }
3794 
3795 static void rdma_reset(struct slgt_info *info)
3796 {
3797 	unsigned int i;
3798 
3799 	/* set reset bit */
3800 	wr_reg32(info, RDCSR, BIT1);
3801 
3802 	/* wait for enable bit cleared */
3803 	for(i=0 ; i < 1000 ; i++)
3804 		if (!(rd_reg32(info, RDCSR) & BIT0))
3805 			break;
3806 }
3807 
3808 static void tdma_reset(struct slgt_info *info)
3809 {
3810 	unsigned int i;
3811 
3812 	/* set reset bit */
3813 	wr_reg32(info, TDCSR, BIT1);
3814 
3815 	/* wait for enable bit cleared */
3816 	for(i=0 ; i < 1000 ; i++)
3817 		if (!(rd_reg32(info, TDCSR) & BIT0))
3818 			break;
3819 }
3820 
3821 /*
3822  * enable internal loopback
3823  * TxCLK and RxCLK are generated from BRG
3824  * and TxD is looped back to RxD internally.
3825  */
3826 static void enable_loopback(struct slgt_info *info)
3827 {
3828 	/* SCR (serial control) BIT2=loopback enable */
3829 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3830 
3831 	if (info->params.mode != MGSL_MODE_ASYNC) {
3832 		/* CCR (clock control)
3833 		 * 07..05  tx clock source (010 = BRG)
3834 		 * 04..02  rx clock source (010 = BRG)
3835 		 * 01      auxclk enable   (0 = disable)
3836 		 * 00      BRG enable      (1 = enable)
3837 		 *
3838 		 * 0100 1001
3839 		 */
3840 		wr_reg8(info, CCR, 0x49);
3841 
3842 		/* set speed if available, otherwise use default */
3843 		if (info->params.clock_speed)
3844 			set_rate(info, info->params.clock_speed);
3845 		else
3846 			set_rate(info, 3686400);
3847 	}
3848 }
3849 
3850 /*
3851  *  set baud rate generator to specified rate
3852  */
3853 static void set_rate(struct slgt_info *info, u32 rate)
3854 {
3855 	unsigned int div;
3856 	unsigned int osc = info->base_clock;
3857 
3858 	/* div = osc/rate - 1
3859 	 *
3860 	 * Round div up if osc/rate is not integer to
3861 	 * force to next slowest rate.
3862 	 */
3863 
3864 	if (rate) {
3865 		div = osc/rate;
3866 		if (!(osc % rate) && div)
3867 			div--;
3868 		wr_reg16(info, BDR, (unsigned short)div);
3869 	}
3870 }
3871 
3872 static void rx_stop(struct slgt_info *info)
3873 {
3874 	unsigned short val;
3875 
3876 	/* disable and reset receiver */
3877 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3878 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3879 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3880 
3881 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3882 
3883 	/* clear pending rx interrupts */
3884 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3885 
3886 	rdma_reset(info);
3887 
3888 	info->rx_enabled = false;
3889 	info->rx_restart = false;
3890 }
3891 
3892 static void rx_start(struct slgt_info *info)
3893 {
3894 	unsigned short val;
3895 
3896 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3897 
3898 	/* clear pending rx overrun IRQ */
3899 	wr_reg16(info, SSR, IRQ_RXOVER);
3900 
3901 	/* reset and disable receiver */
3902 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3903 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3904 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3905 
3906 	rdma_reset(info);
3907 	reset_rbufs(info);
3908 
3909 	if (info->rx_pio) {
3910 		/* rx request when rx FIFO not empty */
3911 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3912 		slgt_irq_on(info, IRQ_RXDATA);
3913 		if (info->params.mode == MGSL_MODE_ASYNC) {
3914 			/* enable saving of rx status */
3915 			wr_reg32(info, RDCSR, BIT6);
3916 		}
3917 	} else {
3918 		/* rx request when rx FIFO half full */
3919 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3920 		/* set 1st descriptor address */
3921 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3922 
3923 		if (info->params.mode != MGSL_MODE_ASYNC) {
3924 			/* enable rx DMA and DMA interrupt */
3925 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3926 		} else {
3927 			/* enable saving of rx status, rx DMA and DMA interrupt */
3928 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3929 		}
3930 	}
3931 
3932 	slgt_irq_on(info, IRQ_RXOVER);
3933 
3934 	/* enable receiver */
3935 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3936 
3937 	info->rx_restart = false;
3938 	info->rx_enabled = true;
3939 }
3940 
3941 static void tx_start(struct slgt_info *info)
3942 {
3943 	if (!info->tx_enabled) {
3944 		wr_reg16(info, TCR,
3945 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3946 		info->tx_enabled = true;
3947 	}
3948 
3949 	if (desc_count(info->tbufs[info->tbuf_start])) {
3950 		info->drop_rts_on_tx_done = false;
3951 
3952 		if (info->params.mode != MGSL_MODE_ASYNC) {
3953 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3954 				get_signals(info);
3955 				if (!(info->signals & SerialSignal_RTS)) {
3956 					info->signals |= SerialSignal_RTS;
3957 					set_signals(info);
3958 					info->drop_rts_on_tx_done = true;
3959 				}
3960 			}
3961 
3962 			slgt_irq_off(info, IRQ_TXDATA);
3963 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3964 			/* clear tx idle and underrun status bits */
3965 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3966 		} else {
3967 			slgt_irq_off(info, IRQ_TXDATA);
3968 			slgt_irq_on(info, IRQ_TXIDLE);
3969 			/* clear tx idle status bit */
3970 			wr_reg16(info, SSR, IRQ_TXIDLE);
3971 		}
3972 		/* set 1st descriptor address and start DMA */
3973 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3974 		wr_reg32(info, TDCSR, BIT2 + BIT0);
3975 		info->tx_active = true;
3976 	}
3977 }
3978 
3979 static void tx_stop(struct slgt_info *info)
3980 {
3981 	unsigned short val;
3982 
3983 	del_timer(&info->tx_timer);
3984 
3985 	tdma_reset(info);
3986 
3987 	/* reset and disable transmitter */
3988 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
3989 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
3990 
3991 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
3992 
3993 	/* clear tx idle and underrun status bit */
3994 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3995 
3996 	reset_tbufs(info);
3997 
3998 	info->tx_enabled = false;
3999 	info->tx_active = false;
4000 }
4001 
4002 static void reset_port(struct slgt_info *info)
4003 {
4004 	if (!info->reg_addr)
4005 		return;
4006 
4007 	tx_stop(info);
4008 	rx_stop(info);
4009 
4010 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4011 	set_signals(info);
4012 
4013 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4014 }
4015 
4016 static void reset_adapter(struct slgt_info *info)
4017 {
4018 	int i;
4019 	for (i=0; i < info->port_count; ++i) {
4020 		if (info->port_array[i])
4021 			reset_port(info->port_array[i]);
4022 	}
4023 }
4024 
4025 static void async_mode(struct slgt_info *info)
4026 {
4027   	unsigned short val;
4028 
4029 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4030 	tx_stop(info);
4031 	rx_stop(info);
4032 
4033 	/* TCR (tx control)
4034 	 *
4035 	 * 15..13  mode, 010=async
4036 	 * 12..10  encoding, 000=NRZ
4037 	 * 09      parity enable
4038 	 * 08      1=odd parity, 0=even parity
4039 	 * 07      1=RTS driver control
4040 	 * 06      1=break enable
4041 	 * 05..04  character length
4042 	 *         00=5 bits
4043 	 *         01=6 bits
4044 	 *         10=7 bits
4045 	 *         11=8 bits
4046 	 * 03      0=1 stop bit, 1=2 stop bits
4047 	 * 02      reset
4048 	 * 01      enable
4049 	 * 00      auto-CTS enable
4050 	 */
4051 	val = 0x4000;
4052 
4053 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4054 		val |= BIT7;
4055 
4056 	if (info->params.parity != ASYNC_PARITY_NONE) {
4057 		val |= BIT9;
4058 		if (info->params.parity == ASYNC_PARITY_ODD)
4059 			val |= BIT8;
4060 	}
4061 
4062 	switch (info->params.data_bits)
4063 	{
4064 	case 6: val |= BIT4; break;
4065 	case 7: val |= BIT5; break;
4066 	case 8: val |= BIT5 + BIT4; break;
4067 	}
4068 
4069 	if (info->params.stop_bits != 1)
4070 		val |= BIT3;
4071 
4072 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4073 		val |= BIT0;
4074 
4075 	wr_reg16(info, TCR, val);
4076 
4077 	/* RCR (rx control)
4078 	 *
4079 	 * 15..13  mode, 010=async
4080 	 * 12..10  encoding, 000=NRZ
4081 	 * 09      parity enable
4082 	 * 08      1=odd parity, 0=even parity
4083 	 * 07..06  reserved, must be 0
4084 	 * 05..04  character length
4085 	 *         00=5 bits
4086 	 *         01=6 bits
4087 	 *         10=7 bits
4088 	 *         11=8 bits
4089 	 * 03      reserved, must be zero
4090 	 * 02      reset
4091 	 * 01      enable
4092 	 * 00      auto-DCD enable
4093 	 */
4094 	val = 0x4000;
4095 
4096 	if (info->params.parity != ASYNC_PARITY_NONE) {
4097 		val |= BIT9;
4098 		if (info->params.parity == ASYNC_PARITY_ODD)
4099 			val |= BIT8;
4100 	}
4101 
4102 	switch (info->params.data_bits)
4103 	{
4104 	case 6: val |= BIT4; break;
4105 	case 7: val |= BIT5; break;
4106 	case 8: val |= BIT5 + BIT4; break;
4107 	}
4108 
4109 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4110 		val |= BIT0;
4111 
4112 	wr_reg16(info, RCR, val);
4113 
4114 	/* CCR (clock control)
4115 	 *
4116 	 * 07..05  011 = tx clock source is BRG/16
4117 	 * 04..02  010 = rx clock source is BRG
4118 	 * 01      0 = auxclk disabled
4119 	 * 00      1 = BRG enabled
4120 	 *
4121 	 * 0110 1001
4122 	 */
4123 	wr_reg8(info, CCR, 0x69);
4124 
4125 	msc_set_vcr(info);
4126 
4127 	/* SCR (serial control)
4128 	 *
4129 	 * 15  1=tx req on FIFO half empty
4130 	 * 14  1=rx req on FIFO half full
4131 	 * 13  tx data  IRQ enable
4132 	 * 12  tx idle  IRQ enable
4133 	 * 11  rx break on IRQ enable
4134 	 * 10  rx data  IRQ enable
4135 	 * 09  rx break off IRQ enable
4136 	 * 08  overrun  IRQ enable
4137 	 * 07  DSR      IRQ enable
4138 	 * 06  CTS      IRQ enable
4139 	 * 05  DCD      IRQ enable
4140 	 * 04  RI       IRQ enable
4141 	 * 03  0=16x sampling, 1=8x sampling
4142 	 * 02  1=txd->rxd internal loopback enable
4143 	 * 01  reserved, must be zero
4144 	 * 00  1=master IRQ enable
4145 	 */
4146 	val = BIT15 + BIT14 + BIT0;
4147 	/* JCR[8] : 1 = x8 async mode feature available */
4148 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4149 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4150 	     (info->base_clock % (info->params.data_rate * 16)))) {
4151 		/* use 8x sampling */
4152 		val |= BIT3;
4153 		set_rate(info, info->params.data_rate * 8);
4154 	} else {
4155 		/* use 16x sampling */
4156 		set_rate(info, info->params.data_rate * 16);
4157 	}
4158 	wr_reg16(info, SCR, val);
4159 
4160 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4161 
4162 	if (info->params.loopback)
4163 		enable_loopback(info);
4164 }
4165 
4166 static void sync_mode(struct slgt_info *info)
4167 {
4168 	unsigned short val;
4169 
4170 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4171 	tx_stop(info);
4172 	rx_stop(info);
4173 
4174 	/* TCR (tx control)
4175 	 *
4176 	 * 15..13  mode
4177 	 *         000=HDLC/SDLC
4178 	 *         001=raw bit synchronous
4179 	 *         010=asynchronous/isochronous
4180 	 *         011=monosync byte synchronous
4181 	 *         100=bisync byte synchronous
4182 	 *         101=xsync byte synchronous
4183 	 * 12..10  encoding
4184 	 * 09      CRC enable
4185 	 * 08      CRC32
4186 	 * 07      1=RTS driver control
4187 	 * 06      preamble enable
4188 	 * 05..04  preamble length
4189 	 * 03      share open/close flag
4190 	 * 02      reset
4191 	 * 01      enable
4192 	 * 00      auto-CTS enable
4193 	 */
4194 	val = BIT2;
4195 
4196 	switch(info->params.mode) {
4197 	case MGSL_MODE_XSYNC:
4198 		val |= BIT15 + BIT13;
4199 		break;
4200 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4201 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4202 	case MGSL_MODE_RAW:      val |= BIT13; break;
4203 	}
4204 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4205 		val |= BIT7;
4206 
4207 	switch(info->params.encoding)
4208 	{
4209 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4210 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4211 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4212 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4213 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4214 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4215 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4216 	}
4217 
4218 	switch (info->params.crc_type & HDLC_CRC_MASK)
4219 	{
4220 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4221 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4222 	}
4223 
4224 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4225 		val |= BIT6;
4226 
4227 	switch (info->params.preamble_length)
4228 	{
4229 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4230 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4231 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4232 	}
4233 
4234 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4235 		val |= BIT0;
4236 
4237 	wr_reg16(info, TCR, val);
4238 
4239 	/* TPR (transmit preamble) */
4240 
4241 	switch (info->params.preamble)
4242 	{
4243 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4244 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4245 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4246 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4247 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4248 	default:                          val = 0x7e; break;
4249 	}
4250 	wr_reg8(info, TPR, (unsigned char)val);
4251 
4252 	/* RCR (rx control)
4253 	 *
4254 	 * 15..13  mode
4255 	 *         000=HDLC/SDLC
4256 	 *         001=raw bit synchronous
4257 	 *         010=asynchronous/isochronous
4258 	 *         011=monosync byte synchronous
4259 	 *         100=bisync byte synchronous
4260 	 *         101=xsync byte synchronous
4261 	 * 12..10  encoding
4262 	 * 09      CRC enable
4263 	 * 08      CRC32
4264 	 * 07..03  reserved, must be 0
4265 	 * 02      reset
4266 	 * 01      enable
4267 	 * 00      auto-DCD enable
4268 	 */
4269 	val = 0;
4270 
4271 	switch(info->params.mode) {
4272 	case MGSL_MODE_XSYNC:
4273 		val |= BIT15 + BIT13;
4274 		break;
4275 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4276 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4277 	case MGSL_MODE_RAW:      val |= BIT13; break;
4278 	}
4279 
4280 	switch(info->params.encoding)
4281 	{
4282 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4283 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4284 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4285 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4286 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4287 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4288 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4289 	}
4290 
4291 	switch (info->params.crc_type & HDLC_CRC_MASK)
4292 	{
4293 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4294 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4295 	}
4296 
4297 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4298 		val |= BIT0;
4299 
4300 	wr_reg16(info, RCR, val);
4301 
4302 	/* CCR (clock control)
4303 	 *
4304 	 * 07..05  tx clock source
4305 	 * 04..02  rx clock source
4306 	 * 01      auxclk enable
4307 	 * 00      BRG enable
4308 	 */
4309 	val = 0;
4310 
4311 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4312 	{
4313 		// when RxC source is DPLL, BRG generates 16X DPLL
4314 		// reference clock, so take TxC from BRG/16 to get
4315 		// transmit clock at actual data rate
4316 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4317 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4318 		else
4319 			val |= BIT6;	/* 010, txclk = BRG */
4320 	}
4321 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4322 		val |= BIT7;	/* 100, txclk = DPLL Input */
4323 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4324 		val |= BIT5;	/* 001, txclk = RXC Input */
4325 
4326 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4327 		val |= BIT3;	/* 010, rxclk = BRG */
4328 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4329 		val |= BIT4;	/* 100, rxclk = DPLL */
4330 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4331 		val |= BIT2;	/* 001, rxclk = TXC Input */
4332 
4333 	if (info->params.clock_speed)
4334 		val |= BIT1 + BIT0;
4335 
4336 	wr_reg8(info, CCR, (unsigned char)val);
4337 
4338 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4339 	{
4340 		// program DPLL mode
4341 		switch(info->params.encoding)
4342 		{
4343 		case HDLC_ENCODING_BIPHASE_MARK:
4344 		case HDLC_ENCODING_BIPHASE_SPACE:
4345 			val = BIT7; break;
4346 		case HDLC_ENCODING_BIPHASE_LEVEL:
4347 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4348 			val = BIT7 + BIT6; break;
4349 		default: val = BIT6;	// NRZ encodings
4350 		}
4351 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4352 
4353 		// DPLL requires a 16X reference clock from BRG
4354 		set_rate(info, info->params.clock_speed * 16);
4355 	}
4356 	else
4357 		set_rate(info, info->params.clock_speed);
4358 
4359 	tx_set_idle(info);
4360 
4361 	msc_set_vcr(info);
4362 
4363 	/* SCR (serial control)
4364 	 *
4365 	 * 15  1=tx req on FIFO half empty
4366 	 * 14  1=rx req on FIFO half full
4367 	 * 13  tx data  IRQ enable
4368 	 * 12  tx idle  IRQ enable
4369 	 * 11  underrun IRQ enable
4370 	 * 10  rx data  IRQ enable
4371 	 * 09  rx idle  IRQ enable
4372 	 * 08  overrun  IRQ enable
4373 	 * 07  DSR      IRQ enable
4374 	 * 06  CTS      IRQ enable
4375 	 * 05  DCD      IRQ enable
4376 	 * 04  RI       IRQ enable
4377 	 * 03  reserved, must be zero
4378 	 * 02  1=txd->rxd internal loopback enable
4379 	 * 01  reserved, must be zero
4380 	 * 00  1=master IRQ enable
4381 	 */
4382 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4383 
4384 	if (info->params.loopback)
4385 		enable_loopback(info);
4386 }
4387 
4388 /*
4389  *  set transmit idle mode
4390  */
4391 static void tx_set_idle(struct slgt_info *info)
4392 {
4393 	unsigned char val;
4394 	unsigned short tcr;
4395 
4396 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4397 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4398 	 */
4399 	tcr = rd_reg16(info, TCR);
4400 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4401 		/* disable preamble, set idle size to 16 bits */
4402 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4403 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4404 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4405 	} else if (!(tcr & BIT6)) {
4406 		/* preamble is disabled, set idle size to 8 bits */
4407 		tcr &= ~(BIT5 + BIT4);
4408 	}
4409 	wr_reg16(info, TCR, tcr);
4410 
4411 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4412 		/* LSB of custom tx idle specified in tx idle register */
4413 		val = (unsigned char)(info->idle_mode & 0xff);
4414 	} else {
4415 		/* standard 8 bit idle patterns */
4416 		switch(info->idle_mode)
4417 		{
4418 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4419 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4420 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4421 		case HDLC_TXIDLE_ZEROS:
4422 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4423 		default:                         val = 0xff;
4424 		}
4425 	}
4426 
4427 	wr_reg8(info, TIR, val);
4428 }
4429 
4430 /*
4431  * get state of V24 status (input) signals
4432  */
4433 static void get_signals(struct slgt_info *info)
4434 {
4435 	unsigned short status = rd_reg16(info, SSR);
4436 
4437 	/* clear all serial signals except RTS and DTR */
4438 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4439 
4440 	if (status & BIT3)
4441 		info->signals |= SerialSignal_DSR;
4442 	if (status & BIT2)
4443 		info->signals |= SerialSignal_CTS;
4444 	if (status & BIT1)
4445 		info->signals |= SerialSignal_DCD;
4446 	if (status & BIT0)
4447 		info->signals |= SerialSignal_RI;
4448 }
4449 
4450 /*
4451  * set V.24 Control Register based on current configuration
4452  */
4453 static void msc_set_vcr(struct slgt_info *info)
4454 {
4455 	unsigned char val = 0;
4456 
4457 	/* VCR (V.24 control)
4458 	 *
4459 	 * 07..04  serial IF select
4460 	 * 03      DTR
4461 	 * 02      RTS
4462 	 * 01      LL
4463 	 * 00      RL
4464 	 */
4465 
4466 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4467 	{
4468 	case MGSL_INTERFACE_RS232:
4469 		val |= BIT5; /* 0010 */
4470 		break;
4471 	case MGSL_INTERFACE_V35:
4472 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4473 		break;
4474 	case MGSL_INTERFACE_RS422:
4475 		val |= BIT6; /* 0100 */
4476 		break;
4477 	}
4478 
4479 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4480 		val |= BIT4;
4481 	if (info->signals & SerialSignal_DTR)
4482 		val |= BIT3;
4483 	if (info->signals & SerialSignal_RTS)
4484 		val |= BIT2;
4485 	if (info->if_mode & MGSL_INTERFACE_LL)
4486 		val |= BIT1;
4487 	if (info->if_mode & MGSL_INTERFACE_RL)
4488 		val |= BIT0;
4489 	wr_reg8(info, VCR, val);
4490 }
4491 
4492 /*
4493  * set state of V24 control (output) signals
4494  */
4495 static void set_signals(struct slgt_info *info)
4496 {
4497 	unsigned char val = rd_reg8(info, VCR);
4498 	if (info->signals & SerialSignal_DTR)
4499 		val |= BIT3;
4500 	else
4501 		val &= ~BIT3;
4502 	if (info->signals & SerialSignal_RTS)
4503 		val |= BIT2;
4504 	else
4505 		val &= ~BIT2;
4506 	wr_reg8(info, VCR, val);
4507 }
4508 
4509 /*
4510  * free range of receive DMA buffers (i to last)
4511  */
4512 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4513 {
4514 	int done = 0;
4515 
4516 	while(!done) {
4517 		/* reset current buffer for reuse */
4518 		info->rbufs[i].status = 0;
4519 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4520 		if (i == last)
4521 			done = 1;
4522 		if (++i == info->rbuf_count)
4523 			i = 0;
4524 	}
4525 	info->rbuf_current = i;
4526 }
4527 
4528 /*
4529  * mark all receive DMA buffers as free
4530  */
4531 static void reset_rbufs(struct slgt_info *info)
4532 {
4533 	free_rbufs(info, 0, info->rbuf_count - 1);
4534 	info->rbuf_fill_index = 0;
4535 	info->rbuf_fill_count = 0;
4536 }
4537 
4538 /*
4539  * pass receive HDLC frame to upper layer
4540  *
4541  * return true if frame available, otherwise false
4542  */
4543 static bool rx_get_frame(struct slgt_info *info)
4544 {
4545 	unsigned int start, end;
4546 	unsigned short status;
4547 	unsigned int framesize = 0;
4548 	unsigned long flags;
4549 	struct tty_struct *tty = info->port.tty;
4550 	unsigned char addr_field = 0xff;
4551 	unsigned int crc_size = 0;
4552 
4553 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4554 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4555 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4556 	}
4557 
4558 check_again:
4559 
4560 	framesize = 0;
4561 	addr_field = 0xff;
4562 	start = end = info->rbuf_current;
4563 
4564 	for (;;) {
4565 		if (!desc_complete(info->rbufs[end]))
4566 			goto cleanup;
4567 
4568 		if (framesize == 0 && info->params.addr_filter != 0xff)
4569 			addr_field = info->rbufs[end].buf[0];
4570 
4571 		framesize += desc_count(info->rbufs[end]);
4572 
4573 		if (desc_eof(info->rbufs[end]))
4574 			break;
4575 
4576 		if (++end == info->rbuf_count)
4577 			end = 0;
4578 
4579 		if (end == info->rbuf_current) {
4580 			if (info->rx_enabled){
4581 				spin_lock_irqsave(&info->lock,flags);
4582 				rx_start(info);
4583 				spin_unlock_irqrestore(&info->lock,flags);
4584 			}
4585 			goto cleanup;
4586 		}
4587 	}
4588 
4589 	/* status
4590 	 *
4591 	 * 15      buffer complete
4592 	 * 14..06  reserved
4593 	 * 05..04  residue
4594 	 * 02      eof (end of frame)
4595 	 * 01      CRC error
4596 	 * 00      abort
4597 	 */
4598 	status = desc_status(info->rbufs[end]);
4599 
4600 	/* ignore CRC bit if not using CRC (bit is undefined) */
4601 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4602 		status &= ~BIT1;
4603 
4604 	if (framesize == 0 ||
4605 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4606 		free_rbufs(info, start, end);
4607 		goto check_again;
4608 	}
4609 
4610 	if (framesize < (2 + crc_size) || status & BIT0) {
4611 		info->icount.rxshort++;
4612 		framesize = 0;
4613 	} else if (status & BIT1) {
4614 		info->icount.rxcrc++;
4615 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4616 			framesize = 0;
4617 	}
4618 
4619 #if SYNCLINK_GENERIC_HDLC
4620 	if (framesize == 0) {
4621 		info->netdev->stats.rx_errors++;
4622 		info->netdev->stats.rx_frame_errors++;
4623 	}
4624 #endif
4625 
4626 	DBGBH(("%s rx frame status=%04X size=%d\n",
4627 		info->device_name, status, framesize));
4628 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4629 
4630 	if (framesize) {
4631 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4632 			framesize -= crc_size;
4633 			crc_size = 0;
4634 		}
4635 
4636 		if (framesize > info->max_frame_size + crc_size)
4637 			info->icount.rxlong++;
4638 		else {
4639 			/* copy dma buffer(s) to contiguous temp buffer */
4640 			int copy_count = framesize;
4641 			int i = start;
4642 			unsigned char *p = info->tmp_rbuf;
4643 			info->tmp_rbuf_count = framesize;
4644 
4645 			info->icount.rxok++;
4646 
4647 			while(copy_count) {
4648 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4649 				memcpy(p, info->rbufs[i].buf, partial_count);
4650 				p += partial_count;
4651 				copy_count -= partial_count;
4652 				if (++i == info->rbuf_count)
4653 					i = 0;
4654 			}
4655 
4656 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4657 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4658 				framesize++;
4659 			}
4660 
4661 #if SYNCLINK_GENERIC_HDLC
4662 			if (info->netcount)
4663 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4664 			else
4665 #endif
4666 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4667 		}
4668 	}
4669 	free_rbufs(info, start, end);
4670 	return true;
4671 
4672 cleanup:
4673 	return false;
4674 }
4675 
4676 /*
4677  * pass receive buffer (RAW synchronous mode) to tty layer
4678  * return true if buffer available, otherwise false
4679  */
4680 static bool rx_get_buf(struct slgt_info *info)
4681 {
4682 	unsigned int i = info->rbuf_current;
4683 	unsigned int count;
4684 
4685 	if (!desc_complete(info->rbufs[i]))
4686 		return false;
4687 	count = desc_count(info->rbufs[i]);
4688 	switch(info->params.mode) {
4689 	case MGSL_MODE_MONOSYNC:
4690 	case MGSL_MODE_BISYNC:
4691 	case MGSL_MODE_XSYNC:
4692 		/* ignore residue in byte synchronous modes */
4693 		if (desc_residue(info->rbufs[i]))
4694 			count--;
4695 		break;
4696 	}
4697 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4698 	DBGINFO(("rx_get_buf size=%d\n", count));
4699 	if (count)
4700 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4701 				  info->flag_buf, count);
4702 	free_rbufs(info, i, i);
4703 	return true;
4704 }
4705 
4706 static void reset_tbufs(struct slgt_info *info)
4707 {
4708 	unsigned int i;
4709 	info->tbuf_current = 0;
4710 	for (i=0 ; i < info->tbuf_count ; i++) {
4711 		info->tbufs[i].status = 0;
4712 		info->tbufs[i].count  = 0;
4713 	}
4714 }
4715 
4716 /*
4717  * return number of free transmit DMA buffers
4718  */
4719 static unsigned int free_tbuf_count(struct slgt_info *info)
4720 {
4721 	unsigned int count = 0;
4722 	unsigned int i = info->tbuf_current;
4723 
4724 	do
4725 	{
4726 		if (desc_count(info->tbufs[i]))
4727 			break; /* buffer in use */
4728 		++count;
4729 		if (++i == info->tbuf_count)
4730 			i=0;
4731 	} while (i != info->tbuf_current);
4732 
4733 	/* if tx DMA active, last zero count buffer is in use */
4734 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4735 		--count;
4736 
4737 	return count;
4738 }
4739 
4740 /*
4741  * return number of bytes in unsent transmit DMA buffers
4742  * and the serial controller tx FIFO
4743  */
4744 static unsigned int tbuf_bytes(struct slgt_info *info)
4745 {
4746 	unsigned int total_count = 0;
4747 	unsigned int i = info->tbuf_current;
4748 	unsigned int reg_value;
4749 	unsigned int count;
4750 	unsigned int active_buf_count = 0;
4751 
4752 	/*
4753 	 * Add descriptor counts for all tx DMA buffers.
4754 	 * If count is zero (cleared by DMA controller after read),
4755 	 * the buffer is complete or is actively being read from.
4756 	 *
4757 	 * Record buf_count of last buffer with zero count starting
4758 	 * from current ring position. buf_count is mirror
4759 	 * copy of count and is not cleared by serial controller.
4760 	 * If DMA controller is active, that buffer is actively
4761 	 * being read so add to total.
4762 	 */
4763 	do {
4764 		count = desc_count(info->tbufs[i]);
4765 		if (count)
4766 			total_count += count;
4767 		else if (!total_count)
4768 			active_buf_count = info->tbufs[i].buf_count;
4769 		if (++i == info->tbuf_count)
4770 			i = 0;
4771 	} while (i != info->tbuf_current);
4772 
4773 	/* read tx DMA status register */
4774 	reg_value = rd_reg32(info, TDCSR);
4775 
4776 	/* if tx DMA active, last zero count buffer is in use */
4777 	if (reg_value & BIT0)
4778 		total_count += active_buf_count;
4779 
4780 	/* add tx FIFO count = reg_value[15..8] */
4781 	total_count += (reg_value >> 8) & 0xff;
4782 
4783 	/* if transmitter active add one byte for shift register */
4784 	if (info->tx_active)
4785 		total_count++;
4786 
4787 	return total_count;
4788 }
4789 
4790 /*
4791  * load data into transmit DMA buffer ring and start transmitter if needed
4792  * return true if data accepted, otherwise false (buffers full)
4793  */
4794 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4795 {
4796 	unsigned short count;
4797 	unsigned int i;
4798 	struct slgt_desc *d;
4799 
4800 	/* check required buffer space */
4801 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4802 		return false;
4803 
4804 	DBGDATA(info, buf, size, "tx");
4805 
4806 	/*
4807 	 * copy data to one or more DMA buffers in circular ring
4808 	 * tbuf_start   = first buffer for this data
4809 	 * tbuf_current = next free buffer
4810 	 *
4811 	 * Copy all data before making data visible to DMA controller by
4812 	 * setting descriptor count of the first buffer.
4813 	 * This prevents an active DMA controller from reading the first DMA
4814 	 * buffers of a frame and stopping before the final buffers are filled.
4815 	 */
4816 
4817 	info->tbuf_start = i = info->tbuf_current;
4818 
4819 	while (size) {
4820 		d = &info->tbufs[i];
4821 
4822 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4823 		memcpy(d->buf, buf, count);
4824 
4825 		size -= count;
4826 		buf  += count;
4827 
4828 		/*
4829 		 * set EOF bit for last buffer of HDLC frame or
4830 		 * for every buffer in raw mode
4831 		 */
4832 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4833 		    info->params.mode == MGSL_MODE_RAW)
4834 			set_desc_eof(*d, 1);
4835 		else
4836 			set_desc_eof(*d, 0);
4837 
4838 		/* set descriptor count for all but first buffer */
4839 		if (i != info->tbuf_start)
4840 			set_desc_count(*d, count);
4841 		d->buf_count = count;
4842 
4843 		if (++i == info->tbuf_count)
4844 			i = 0;
4845 	}
4846 
4847 	info->tbuf_current = i;
4848 
4849 	/* set first buffer count to make new data visible to DMA controller */
4850 	d = &info->tbufs[info->tbuf_start];
4851 	set_desc_count(*d, d->buf_count);
4852 
4853 	/* start transmitter if needed and update transmit timeout */
4854 	if (!info->tx_active)
4855 		tx_start(info);
4856 	update_tx_timer(info);
4857 
4858 	return true;
4859 }
4860 
4861 static int register_test(struct slgt_info *info)
4862 {
4863 	static unsigned short patterns[] =
4864 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4865 	static unsigned int count = ARRAY_SIZE(patterns);
4866 	unsigned int i;
4867 	int rc = 0;
4868 
4869 	for (i=0 ; i < count ; i++) {
4870 		wr_reg16(info, TIR, patterns[i]);
4871 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4872 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4873 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4874 			rc = -ENODEV;
4875 			break;
4876 		}
4877 	}
4878 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4879 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4880 	return rc;
4881 }
4882 
4883 static int irq_test(struct slgt_info *info)
4884 {
4885 	unsigned long timeout;
4886 	unsigned long flags;
4887 	struct tty_struct *oldtty = info->port.tty;
4888 	u32 speed = info->params.data_rate;
4889 
4890 	info->params.data_rate = 921600;
4891 	info->port.tty = NULL;
4892 
4893 	spin_lock_irqsave(&info->lock, flags);
4894 	async_mode(info);
4895 	slgt_irq_on(info, IRQ_TXIDLE);
4896 
4897 	/* enable transmitter */
4898 	wr_reg16(info, TCR,
4899 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4900 
4901 	/* write one byte and wait for tx idle */
4902 	wr_reg16(info, TDR, 0);
4903 
4904 	/* assume failure */
4905 	info->init_error = DiagStatus_IrqFailure;
4906 	info->irq_occurred = false;
4907 
4908 	spin_unlock_irqrestore(&info->lock, flags);
4909 
4910 	timeout=100;
4911 	while(timeout-- && !info->irq_occurred)
4912 		msleep_interruptible(10);
4913 
4914 	spin_lock_irqsave(&info->lock,flags);
4915 	reset_port(info);
4916 	spin_unlock_irqrestore(&info->lock,flags);
4917 
4918 	info->params.data_rate = speed;
4919 	info->port.tty = oldtty;
4920 
4921 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4922 	return info->irq_occurred ? 0 : -ENODEV;
4923 }
4924 
4925 static int loopback_test_rx(struct slgt_info *info)
4926 {
4927 	unsigned char *src, *dest;
4928 	int count;
4929 
4930 	if (desc_complete(info->rbufs[0])) {
4931 		count = desc_count(info->rbufs[0]);
4932 		src   = info->rbufs[0].buf;
4933 		dest  = info->tmp_rbuf;
4934 
4935 		for( ; count ; count-=2, src+=2) {
4936 			/* src=data byte (src+1)=status byte */
4937 			if (!(*(src+1) & (BIT9 + BIT8))) {
4938 				*dest = *src;
4939 				dest++;
4940 				info->tmp_rbuf_count++;
4941 			}
4942 		}
4943 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4944 		return 1;
4945 	}
4946 	return 0;
4947 }
4948 
4949 static int loopback_test(struct slgt_info *info)
4950 {
4951 #define TESTFRAMESIZE 20
4952 
4953 	unsigned long timeout;
4954 	u16 count;
4955 	unsigned char buf[TESTFRAMESIZE];
4956 	int rc = -ENODEV;
4957 	unsigned long flags;
4958 
4959 	struct tty_struct *oldtty = info->port.tty;
4960 	MGSL_PARAMS params;
4961 
4962 	memcpy(&params, &info->params, sizeof(params));
4963 
4964 	info->params.mode = MGSL_MODE_ASYNC;
4965 	info->params.data_rate = 921600;
4966 	info->params.loopback = 1;
4967 	info->port.tty = NULL;
4968 
4969 	/* build and send transmit frame */
4970 	for (count = 0; count < TESTFRAMESIZE; ++count)
4971 		buf[count] = (unsigned char)count;
4972 
4973 	info->tmp_rbuf_count = 0;
4974 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4975 
4976 	/* program hardware for HDLC and enabled receiver */
4977 	spin_lock_irqsave(&info->lock,flags);
4978 	async_mode(info);
4979 	rx_start(info);
4980 	tx_load(info, buf, count);
4981 	spin_unlock_irqrestore(&info->lock, flags);
4982 
4983 	/* wait for receive complete */
4984 	for (timeout = 100; timeout; --timeout) {
4985 		msleep_interruptible(10);
4986 		if (loopback_test_rx(info)) {
4987 			rc = 0;
4988 			break;
4989 		}
4990 	}
4991 
4992 	/* verify received frame length and contents */
4993 	if (!rc && (info->tmp_rbuf_count != count ||
4994 		  memcmp(buf, info->tmp_rbuf, count))) {
4995 		rc = -ENODEV;
4996 	}
4997 
4998 	spin_lock_irqsave(&info->lock,flags);
4999 	reset_adapter(info);
5000 	spin_unlock_irqrestore(&info->lock,flags);
5001 
5002 	memcpy(&info->params, &params, sizeof(info->params));
5003 	info->port.tty = oldtty;
5004 
5005 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5006 	return rc;
5007 }
5008 
5009 static int adapter_test(struct slgt_info *info)
5010 {
5011 	DBGINFO(("testing %s\n", info->device_name));
5012 	if (register_test(info) < 0) {
5013 		printk("register test failure %s addr=%08X\n",
5014 			info->device_name, info->phys_reg_addr);
5015 	} else if (irq_test(info) < 0) {
5016 		printk("IRQ test failure %s IRQ=%d\n",
5017 			info->device_name, info->irq_level);
5018 	} else if (loopback_test(info) < 0) {
5019 		printk("loopback test failure %s\n", info->device_name);
5020 	}
5021 	return info->init_error;
5022 }
5023 
5024 /*
5025  * transmit timeout handler
5026  */
5027 static void tx_timeout(struct timer_list *t)
5028 {
5029 	struct slgt_info *info = from_timer(info, t, tx_timer);
5030 	unsigned long flags;
5031 
5032 	DBGINFO(("%s tx_timeout\n", info->device_name));
5033 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5034 		info->icount.txtimeout++;
5035 	}
5036 	spin_lock_irqsave(&info->lock,flags);
5037 	tx_stop(info);
5038 	spin_unlock_irqrestore(&info->lock,flags);
5039 
5040 #if SYNCLINK_GENERIC_HDLC
5041 	if (info->netcount)
5042 		hdlcdev_tx_done(info);
5043 	else
5044 #endif
5045 		bh_transmit(info);
5046 }
5047 
5048 /*
5049  * receive buffer polling timer
5050  */
5051 static void rx_timeout(struct timer_list *t)
5052 {
5053 	struct slgt_info *info = from_timer(info, t, rx_timer);
5054 	unsigned long flags;
5055 
5056 	DBGINFO(("%s rx_timeout\n", info->device_name));
5057 	spin_lock_irqsave(&info->lock, flags);
5058 	info->pending_bh |= BH_RECEIVE;
5059 	spin_unlock_irqrestore(&info->lock, flags);
5060 	bh_handler(&info->task);
5061 }
5062 
5063