xref: /linux/drivers/tty/synclink_gt.c (revision 9b5aa54986fc85f5e10045348a8a45894aeb18db)
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 MAX_DEVICES 32
95 
96 static const struct pci_device_id pci_table[] = {
97 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
98 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101 	{0,}, /* terminate list */
102 };
103 MODULE_DEVICE_TABLE(pci, pci_table);
104 
105 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
106 static void remove_one(struct pci_dev *dev);
107 static struct pci_driver pci_driver = {
108 	.name		= "synclink_gt",
109 	.id_table	= pci_table,
110 	.probe		= init_one,
111 	.remove		= remove_one,
112 };
113 
114 static bool pci_registered;
115 
116 /*
117  * module configuration and status
118  */
119 static struct slgt_info *slgt_device_list;
120 static int slgt_device_count;
121 
122 static int ttymajor;
123 static int debug_level;
124 static int maxframe[MAX_DEVICES];
125 
126 module_param(ttymajor, int, 0);
127 module_param(debug_level, int, 0);
128 module_param_array(maxframe, int, NULL, 0);
129 
130 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
131 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
132 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
133 
134 /*
135  * tty support and callbacks
136  */
137 static struct tty_driver *serial_driver;
138 
139 static void wait_until_sent(struct tty_struct *tty, int timeout);
140 static void flush_buffer(struct tty_struct *tty);
141 static void tx_release(struct tty_struct *tty);
142 
143 /*
144  * generic HDLC support
145  */
146 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
147 
148 
149 /*
150  * device specific structures, macros and functions
151  */
152 
153 #define SLGT_MAX_PORTS 4
154 #define SLGT_REG_SIZE  256
155 
156 /*
157  * conditional wait facility
158  */
159 struct cond_wait {
160 	struct cond_wait *next;
161 	wait_queue_head_t q;
162 	wait_queue_entry_t wait;
163 	unsigned int data;
164 };
165 static void flush_cond_wait(struct cond_wait **head);
166 
167 /*
168  * DMA buffer descriptor and access macros
169  */
170 struct slgt_desc
171 {
172 	__le16 count;
173 	__le16 status;
174 	__le32 pbuf;  /* physical address of data buffer */
175 	__le32 next;  /* physical address of next descriptor */
176 
177 	/* driver book keeping */
178 	char *buf;          /* virtual  address of data buffer */
179     	unsigned int pdesc; /* physical address of this descriptor */
180 	dma_addr_t buf_dma_addr;
181 	unsigned short buf_count;
182 };
183 
184 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
185 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
186 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
187 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
188 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
189 #define desc_count(a)      (le16_to_cpu((a).count))
190 #define desc_status(a)     (le16_to_cpu((a).status))
191 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
192 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
193 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
194 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
195 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
196 
197 struct _input_signal_events {
198 	int ri_up;
199 	int ri_down;
200 	int dsr_up;
201 	int dsr_down;
202 	int dcd_up;
203 	int dcd_down;
204 	int cts_up;
205 	int cts_down;
206 };
207 
208 /*
209  * device instance data structure
210  */
211 struct slgt_info {
212 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
213 	struct tty_port port;
214 
215 	struct slgt_info *next_device;	/* device list link */
216 
217 	char device_name[25];
218 	struct pci_dev *pdev;
219 
220 	int port_count;  /* count of ports on adapter */
221 	int adapter_num; /* adapter instance number */
222 	int port_num;    /* port instance number */
223 
224 	/* array of pointers to port contexts on this adapter */
225 	struct slgt_info *port_array[SLGT_MAX_PORTS];
226 
227 	int			line;		/* tty line instance number */
228 
229 	struct mgsl_icount	icount;
230 
231 	int			timeout;
232 	int			x_char;		/* xon/xoff character */
233 	unsigned int		read_status_mask;
234 	unsigned int 		ignore_status_mask;
235 
236 	wait_queue_head_t	status_event_wait_q;
237 	wait_queue_head_t	event_wait_q;
238 	struct timer_list	tx_timer;
239 	struct timer_list	rx_timer;
240 
241 	unsigned int            gpio_present;
242 	struct cond_wait        *gpio_wait_q;
243 
244 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
245 
246 	struct work_struct task;
247 	u32 pending_bh;
248 	bool bh_requested;
249 	bool bh_running;
250 
251 	int isr_overflow;
252 	bool irq_requested;	/* true if IRQ requested */
253 	bool irq_occurred;	/* for diagnostics use */
254 
255 	/* device configuration */
256 
257 	unsigned int bus_type;
258 	unsigned int irq_level;
259 	unsigned long irq_flags;
260 
261 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
262 	u32 phys_reg_addr;
263 	bool reg_addr_requested;
264 
265 	MGSL_PARAMS params;       /* communications parameters */
266 	u32 idle_mode;
267 	u32 max_frame_size;       /* as set by device config */
268 
269 	unsigned int rbuf_fill_level;
270 	unsigned int rx_pio;
271 	unsigned int if_mode;
272 	unsigned int base_clock;
273 	unsigned int xsync;
274 	unsigned int xctrl;
275 
276 	/* device status */
277 
278 	bool rx_enabled;
279 	bool rx_restart;
280 
281 	bool tx_enabled;
282 	bool tx_active;
283 
284 	unsigned char signals;    /* serial signal states */
285 	int init_error;  /* initialization error */
286 
287 	unsigned char *tx_buf;
288 	int tx_count;
289 
290 	char *flag_buf;
291 	bool drop_rts_on_tx_done;
292 	struct	_input_signal_events	input_signal_events;
293 
294 	int dcd_chkcount;	/* check counts to prevent */
295 	int cts_chkcount;	/* too many IRQs if a signal */
296 	int dsr_chkcount;	/* is floating */
297 	int ri_chkcount;
298 
299 	char *bufs;		/* virtual address of DMA buffer lists */
300 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
301 
302 	unsigned int rbuf_count;
303 	struct slgt_desc *rbufs;
304 	unsigned int rbuf_current;
305 	unsigned int rbuf_index;
306 	unsigned int rbuf_fill_index;
307 	unsigned short rbuf_fill_count;
308 
309 	unsigned int tbuf_count;
310 	struct slgt_desc *tbufs;
311 	unsigned int tbuf_current;
312 	unsigned int tbuf_start;
313 
314 	unsigned char *tmp_rbuf;
315 	unsigned int tmp_rbuf_count;
316 
317 	/* SPPP/Cisco HDLC device parts */
318 
319 	int netcount;
320 	spinlock_t netlock;
321 #if SYNCLINK_GENERIC_HDLC
322 	struct net_device *netdev;
323 #endif
324 
325 };
326 
327 static MGSL_PARAMS default_params = {
328 	.mode            = MGSL_MODE_HDLC,
329 	.loopback        = 0,
330 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
331 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
332 	.clock_speed     = 0,
333 	.addr_filter     = 0xff,
334 	.crc_type        = HDLC_CRC_16_CCITT,
335 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
336 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
337 	.data_rate       = 9600,
338 	.data_bits       = 8,
339 	.stop_bits       = 1,
340 	.parity          = ASYNC_PARITY_NONE
341 };
342 
343 
344 #define BH_RECEIVE  1
345 #define BH_TRANSMIT 2
346 #define BH_STATUS   4
347 #define IO_PIN_SHUTDOWN_LIMIT 100
348 
349 #define DMABUFSIZE 256
350 #define DESC_LIST_SIZE 4096
351 
352 #define MASK_PARITY  BIT1
353 #define MASK_FRAMING BIT0
354 #define MASK_BREAK   BIT14
355 #define MASK_OVERRUN BIT4
356 
357 #define GSR   0x00 /* global status */
358 #define JCR   0x04 /* JTAG control */
359 #define IODR  0x08 /* GPIO direction */
360 #define IOER  0x0c /* GPIO interrupt enable */
361 #define IOVR  0x10 /* GPIO value */
362 #define IOSR  0x14 /* GPIO interrupt status */
363 #define TDR   0x80 /* tx data */
364 #define RDR   0x80 /* rx data */
365 #define TCR   0x82 /* tx control */
366 #define TIR   0x84 /* tx idle */
367 #define TPR   0x85 /* tx preamble */
368 #define RCR   0x86 /* rx control */
369 #define VCR   0x88 /* V.24 control */
370 #define CCR   0x89 /* clock control */
371 #define BDR   0x8a /* baud divisor */
372 #define SCR   0x8c /* serial control */
373 #define SSR   0x8e /* serial status */
374 #define RDCSR 0x90 /* rx DMA control/status */
375 #define TDCSR 0x94 /* tx DMA control/status */
376 #define RDDAR 0x98 /* rx DMA descriptor address */
377 #define TDDAR 0x9c /* tx DMA descriptor address */
378 #define XSR   0x40 /* extended sync pattern */
379 #define XCR   0x44 /* extended control */
380 
381 #define RXIDLE      BIT14
382 #define RXBREAK     BIT14
383 #define IRQ_TXDATA  BIT13
384 #define IRQ_TXIDLE  BIT12
385 #define IRQ_TXUNDER BIT11 /* HDLC */
386 #define IRQ_RXDATA  BIT10
387 #define IRQ_RXIDLE  BIT9  /* HDLC */
388 #define IRQ_RXBREAK BIT9  /* async */
389 #define IRQ_RXOVER  BIT8
390 #define IRQ_DSR     BIT7
391 #define IRQ_CTS     BIT6
392 #define IRQ_DCD     BIT5
393 #define IRQ_RI      BIT4
394 #define IRQ_ALL     0x3ff0
395 #define IRQ_MASTER  BIT0
396 
397 #define slgt_irq_on(info, mask) \
398 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
399 #define slgt_irq_off(info, mask) \
400 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
401 
402 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
403 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
404 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
405 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
406 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
407 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
408 
409 static void  msc_set_vcr(struct slgt_info *info);
410 
411 static int  startup(struct slgt_info *info);
412 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
413 static void shutdown(struct slgt_info *info);
414 static void program_hw(struct slgt_info *info);
415 static void change_params(struct slgt_info *info);
416 
417 static int  adapter_test(struct slgt_info *info);
418 
419 static void reset_port(struct slgt_info *info);
420 static void async_mode(struct slgt_info *info);
421 static void sync_mode(struct slgt_info *info);
422 
423 static void rx_stop(struct slgt_info *info);
424 static void rx_start(struct slgt_info *info);
425 static void reset_rbufs(struct slgt_info *info);
426 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
427 static bool rx_get_frame(struct slgt_info *info);
428 static bool rx_get_buf(struct slgt_info *info);
429 
430 static void tx_start(struct slgt_info *info);
431 static void tx_stop(struct slgt_info *info);
432 static void tx_set_idle(struct slgt_info *info);
433 static unsigned int tbuf_bytes(struct slgt_info *info);
434 static void reset_tbufs(struct slgt_info *info);
435 static void tdma_reset(struct slgt_info *info);
436 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
437 
438 static void get_gtsignals(struct slgt_info *info);
439 static void set_gtsignals(struct slgt_info *info);
440 static void set_rate(struct slgt_info *info, u32 data_rate);
441 
442 static void bh_transmit(struct slgt_info *info);
443 static void isr_txeom(struct slgt_info *info, unsigned short status);
444 
445 static void tx_timeout(struct timer_list *t);
446 static void rx_timeout(struct timer_list *t);
447 
448 /*
449  * ioctl handlers
450  */
451 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
452 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
453 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
454 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
455 static int  set_txidle(struct slgt_info *info, int idle_mode);
456 static int  tx_enable(struct slgt_info *info, int enable);
457 static int  tx_abort(struct slgt_info *info);
458 static int  rx_enable(struct slgt_info *info, int enable);
459 static int  modem_input_wait(struct slgt_info *info,int arg);
460 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
461 static int  get_interface(struct slgt_info *info, int __user *if_mode);
462 static int  set_interface(struct slgt_info *info, int if_mode);
463 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
464 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
465 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
466 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
467 static int  set_xsync(struct slgt_info *info, int if_mode);
468 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
469 static int  set_xctrl(struct slgt_info *info, int if_mode);
470 
471 /*
472  * driver functions
473  */
474 static void release_resources(struct slgt_info *info);
475 
476 /*
477  * DEBUG OUTPUT CODE
478  */
479 #ifndef DBGINFO
480 #define DBGINFO(fmt)
481 #endif
482 #ifndef DBGERR
483 #define DBGERR(fmt)
484 #endif
485 #ifndef DBGBH
486 #define DBGBH(fmt)
487 #endif
488 #ifndef DBGISR
489 #define DBGISR(fmt)
490 #endif
491 
492 #ifdef DBGDATA
493 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
494 {
495 	int i;
496 	int linecount;
497 	printk("%s %s data:\n",info->device_name, label);
498 	while(count) {
499 		linecount = (count > 16) ? 16 : count;
500 		for(i=0; i < linecount; i++)
501 			printk("%02X ",(unsigned char)data[i]);
502 		for(;i<17;i++)
503 			printk("   ");
504 		for(i=0;i<linecount;i++) {
505 			if (data[i]>=040 && data[i]<=0176)
506 				printk("%c",data[i]);
507 			else
508 				printk(".");
509 		}
510 		printk("\n");
511 		data  += linecount;
512 		count -= linecount;
513 	}
514 }
515 #else
516 #define DBGDATA(info, buf, size, label)
517 #endif
518 
519 #ifdef DBGTBUF
520 static void dump_tbufs(struct slgt_info *info)
521 {
522 	int i;
523 	printk("tbuf_current=%d\n", info->tbuf_current);
524 	for (i=0 ; i < info->tbuf_count ; i++) {
525 		printk("%d: count=%04X status=%04X\n",
526 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
527 	}
528 }
529 #else
530 #define DBGTBUF(info)
531 #endif
532 
533 #ifdef DBGRBUF
534 static void dump_rbufs(struct slgt_info *info)
535 {
536 	int i;
537 	printk("rbuf_current=%d\n", info->rbuf_current);
538 	for (i=0 ; i < info->rbuf_count ; i++) {
539 		printk("%d: count=%04X status=%04X\n",
540 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
541 	}
542 }
543 #else
544 #define DBGRBUF(info)
545 #endif
546 
547 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
548 {
549 #ifdef SANITY_CHECK
550 	if (!info) {
551 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
552 		return 1;
553 	}
554 #else
555 	if (!info)
556 		return 1;
557 #endif
558 	return 0;
559 }
560 
561 /*
562  * line discipline callback wrappers
563  *
564  * The wrappers maintain line discipline references
565  * while calling into the line discipline.
566  *
567  * ldisc_receive_buf  - pass receive data to line discipline
568  */
569 static void ldisc_receive_buf(struct tty_struct *tty,
570 			      const __u8 *data, char *flags, int count)
571 {
572 	struct tty_ldisc *ld;
573 	if (!tty)
574 		return;
575 	ld = tty_ldisc_ref(tty);
576 	if (ld) {
577 		if (ld->ops->receive_buf)
578 			ld->ops->receive_buf(tty, data, flags, count);
579 		tty_ldisc_deref(ld);
580 	}
581 }
582 
583 /* tty callbacks */
584 
585 static int open(struct tty_struct *tty, struct file *filp)
586 {
587 	struct slgt_info *info;
588 	int retval, line;
589 	unsigned long flags;
590 
591 	line = tty->index;
592 	if (line >= slgt_device_count) {
593 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
594 		return -ENODEV;
595 	}
596 
597 	info = slgt_device_list;
598 	while(info && info->line != line)
599 		info = info->next_device;
600 	if (sanity_check(info, tty->name, "open"))
601 		return -ENODEV;
602 	if (info->init_error) {
603 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
604 		return -ENODEV;
605 	}
606 
607 	tty->driver_data = info;
608 	info->port.tty = tty;
609 
610 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
611 
612 	mutex_lock(&info->port.mutex);
613 
614 	spin_lock_irqsave(&info->netlock, flags);
615 	if (info->netcount) {
616 		retval = -EBUSY;
617 		spin_unlock_irqrestore(&info->netlock, flags);
618 		mutex_unlock(&info->port.mutex);
619 		goto cleanup;
620 	}
621 	info->port.count++;
622 	spin_unlock_irqrestore(&info->netlock, flags);
623 
624 	if (info->port.count == 1) {
625 		/* 1st open on this device, init hardware */
626 		retval = startup(info);
627 		if (retval < 0) {
628 			mutex_unlock(&info->port.mutex);
629 			goto cleanup;
630 		}
631 	}
632 	mutex_unlock(&info->port.mutex);
633 	retval = block_til_ready(tty, filp, info);
634 	if (retval) {
635 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
636 		goto cleanup;
637 	}
638 
639 	retval = 0;
640 
641 cleanup:
642 	if (retval) {
643 		if (tty->count == 1)
644 			info->port.tty = NULL; /* tty layer will release tty struct */
645 		if(info->port.count)
646 			info->port.count--;
647 	}
648 
649 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
650 	return retval;
651 }
652 
653 static void close(struct tty_struct *tty, struct file *filp)
654 {
655 	struct slgt_info *info = tty->driver_data;
656 
657 	if (sanity_check(info, tty->name, "close"))
658 		return;
659 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
660 
661 	if (tty_port_close_start(&info->port, tty, filp) == 0)
662 		goto cleanup;
663 
664 	mutex_lock(&info->port.mutex);
665 	if (tty_port_initialized(&info->port))
666  		wait_until_sent(tty, info->timeout);
667 	flush_buffer(tty);
668 	tty_ldisc_flush(tty);
669 
670 	shutdown(info);
671 	mutex_unlock(&info->port.mutex);
672 
673 	tty_port_close_end(&info->port, tty);
674 	info->port.tty = NULL;
675 cleanup:
676 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
677 }
678 
679 static void hangup(struct tty_struct *tty)
680 {
681 	struct slgt_info *info = tty->driver_data;
682 	unsigned long flags;
683 
684 	if (sanity_check(info, tty->name, "hangup"))
685 		return;
686 	DBGINFO(("%s hangup\n", info->device_name));
687 
688 	flush_buffer(tty);
689 
690 	mutex_lock(&info->port.mutex);
691 	shutdown(info);
692 
693 	spin_lock_irqsave(&info->port.lock, flags);
694 	info->port.count = 0;
695 	info->port.tty = NULL;
696 	spin_unlock_irqrestore(&info->port.lock, flags);
697 	tty_port_set_active(&info->port, false);
698 	mutex_unlock(&info->port.mutex);
699 
700 	wake_up_interruptible(&info->port.open_wait);
701 }
702 
703 static void set_termios(struct tty_struct *tty,
704 			const struct ktermios *old_termios)
705 {
706 	struct slgt_info *info = tty->driver_data;
707 	unsigned long flags;
708 
709 	DBGINFO(("%s set_termios\n", tty->driver->name));
710 
711 	change_params(info);
712 
713 	/* Handle transition to B0 status */
714 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
715 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
716 		spin_lock_irqsave(&info->lock,flags);
717 		set_gtsignals(info);
718 		spin_unlock_irqrestore(&info->lock,flags);
719 	}
720 
721 	/* Handle transition away from B0 status */
722 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
723 		info->signals |= SerialSignal_DTR;
724 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
725 			info->signals |= SerialSignal_RTS;
726 		spin_lock_irqsave(&info->lock,flags);
727 	 	set_gtsignals(info);
728 		spin_unlock_irqrestore(&info->lock,flags);
729 	}
730 
731 	/* Handle turning off CRTSCTS */
732 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
733 		tty->hw_stopped = 0;
734 		tx_release(tty);
735 	}
736 }
737 
738 static void update_tx_timer(struct slgt_info *info)
739 {
740 	/*
741 	 * use worst case speed of 1200bps to calculate transmit timeout
742 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
743 	 */
744 	if (info->params.mode == MGSL_MODE_HDLC) {
745 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
746 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
747 	}
748 }
749 
750 static int write(struct tty_struct *tty,
751 		 const unsigned char *buf, int count)
752 {
753 	int ret = 0;
754 	struct slgt_info *info = tty->driver_data;
755 	unsigned long flags;
756 
757 	if (sanity_check(info, tty->name, "write"))
758 		return -EIO;
759 
760 	DBGINFO(("%s write count=%d\n", info->device_name, count));
761 
762 	if (!info->tx_buf || (count > info->max_frame_size))
763 		return -EIO;
764 
765 	if (!count || tty->flow.stopped || tty->hw_stopped)
766 		return 0;
767 
768 	spin_lock_irqsave(&info->lock, flags);
769 
770 	if (info->tx_count) {
771 		/* send accumulated data from send_char() */
772 		if (!tx_load(info, info->tx_buf, info->tx_count))
773 			goto cleanup;
774 		info->tx_count = 0;
775 	}
776 
777 	if (tx_load(info, buf, count))
778 		ret = count;
779 
780 cleanup:
781 	spin_unlock_irqrestore(&info->lock, flags);
782 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
783 	return ret;
784 }
785 
786 static int put_char(struct tty_struct *tty, unsigned char ch)
787 {
788 	struct slgt_info *info = tty->driver_data;
789 	unsigned long flags;
790 	int ret = 0;
791 
792 	if (sanity_check(info, tty->name, "put_char"))
793 		return 0;
794 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
795 	if (!info->tx_buf)
796 		return 0;
797 	spin_lock_irqsave(&info->lock,flags);
798 	if (info->tx_count < info->max_frame_size) {
799 		info->tx_buf[info->tx_count++] = ch;
800 		ret = 1;
801 	}
802 	spin_unlock_irqrestore(&info->lock,flags);
803 	return ret;
804 }
805 
806 static void send_xchar(struct tty_struct *tty, char ch)
807 {
808 	struct slgt_info *info = tty->driver_data;
809 	unsigned long flags;
810 
811 	if (sanity_check(info, tty->name, "send_xchar"))
812 		return;
813 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
814 	info->x_char = ch;
815 	if (ch) {
816 		spin_lock_irqsave(&info->lock,flags);
817 		if (!info->tx_enabled)
818 		 	tx_start(info);
819 		spin_unlock_irqrestore(&info->lock,flags);
820 	}
821 }
822 
823 static void wait_until_sent(struct tty_struct *tty, int timeout)
824 {
825 	struct slgt_info *info = tty->driver_data;
826 	unsigned long orig_jiffies, char_time;
827 
828 	if (!info )
829 		return;
830 	if (sanity_check(info, tty->name, "wait_until_sent"))
831 		return;
832 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
833 	if (!tty_port_initialized(&info->port))
834 		goto exit;
835 
836 	orig_jiffies = jiffies;
837 
838 	/* Set check interval to 1/5 of estimated time to
839 	 * send a character, and make it at least 1. The check
840 	 * interval should also be less than the timeout.
841 	 * Note: use tight timings here to satisfy the NIST-PCTS.
842 	 */
843 
844 	if (info->params.data_rate) {
845 	       	char_time = info->timeout/(32 * 5);
846 		if (!char_time)
847 			char_time++;
848 	} else
849 		char_time = 1;
850 
851 	if (timeout)
852 		char_time = min_t(unsigned long, char_time, timeout);
853 
854 	while (info->tx_active) {
855 		msleep_interruptible(jiffies_to_msecs(char_time));
856 		if (signal_pending(current))
857 			break;
858 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
859 			break;
860 	}
861 exit:
862 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
863 }
864 
865 static unsigned int write_room(struct tty_struct *tty)
866 {
867 	struct slgt_info *info = tty->driver_data;
868 	unsigned int ret;
869 
870 	if (sanity_check(info, tty->name, "write_room"))
871 		return 0;
872 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
873 	DBGINFO(("%s write_room=%u\n", info->device_name, ret));
874 	return ret;
875 }
876 
877 static void flush_chars(struct tty_struct *tty)
878 {
879 	struct slgt_info *info = tty->driver_data;
880 	unsigned long flags;
881 
882 	if (sanity_check(info, tty->name, "flush_chars"))
883 		return;
884 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
885 
886 	if (info->tx_count <= 0 || tty->flow.stopped ||
887 	    tty->hw_stopped || !info->tx_buf)
888 		return;
889 
890 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
891 
892 	spin_lock_irqsave(&info->lock,flags);
893 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
894 		info->tx_count = 0;
895 	spin_unlock_irqrestore(&info->lock,flags);
896 }
897 
898 static void flush_buffer(struct tty_struct *tty)
899 {
900 	struct slgt_info *info = tty->driver_data;
901 	unsigned long flags;
902 
903 	if (sanity_check(info, tty->name, "flush_buffer"))
904 		return;
905 	DBGINFO(("%s flush_buffer\n", info->device_name));
906 
907 	spin_lock_irqsave(&info->lock, flags);
908 	info->tx_count = 0;
909 	spin_unlock_irqrestore(&info->lock, flags);
910 
911 	tty_wakeup(tty);
912 }
913 
914 /*
915  * throttle (stop) transmitter
916  */
917 static void tx_hold(struct tty_struct *tty)
918 {
919 	struct slgt_info *info = tty->driver_data;
920 	unsigned long flags;
921 
922 	if (sanity_check(info, tty->name, "tx_hold"))
923 		return;
924 	DBGINFO(("%s tx_hold\n", info->device_name));
925 	spin_lock_irqsave(&info->lock,flags);
926 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
927 	 	tx_stop(info);
928 	spin_unlock_irqrestore(&info->lock,flags);
929 }
930 
931 /*
932  * release (start) transmitter
933  */
934 static void tx_release(struct tty_struct *tty)
935 {
936 	struct slgt_info *info = tty->driver_data;
937 	unsigned long flags;
938 
939 	if (sanity_check(info, tty->name, "tx_release"))
940 		return;
941 	DBGINFO(("%s tx_release\n", info->device_name));
942 	spin_lock_irqsave(&info->lock, flags);
943 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
944 		info->tx_count = 0;
945 	spin_unlock_irqrestore(&info->lock, flags);
946 }
947 
948 /*
949  * Service an IOCTL request
950  *
951  * Arguments
952  *
953  * 	tty	pointer to tty instance data
954  * 	cmd	IOCTL command code
955  * 	arg	command argument/context
956  *
957  * Return 0 if success, otherwise error code
958  */
959 static int ioctl(struct tty_struct *tty,
960 		 unsigned int cmd, unsigned long arg)
961 {
962 	struct slgt_info *info = tty->driver_data;
963 	void __user *argp = (void __user *)arg;
964 	int ret;
965 
966 	if (sanity_check(info, tty->name, "ioctl"))
967 		return -ENODEV;
968 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
969 
970 	if (cmd != TIOCMIWAIT) {
971 		if (tty_io_error(tty))
972 		    return -EIO;
973 	}
974 
975 	switch (cmd) {
976 	case MGSL_IOCWAITEVENT:
977 		return wait_mgsl_event(info, argp);
978 	case TIOCMIWAIT:
979 		return modem_input_wait(info,(int)arg);
980 	case MGSL_IOCSGPIO:
981 		return set_gpio(info, argp);
982 	case MGSL_IOCGGPIO:
983 		return get_gpio(info, argp);
984 	case MGSL_IOCWAITGPIO:
985 		return wait_gpio(info, argp);
986 	case MGSL_IOCGXSYNC:
987 		return get_xsync(info, argp);
988 	case MGSL_IOCSXSYNC:
989 		return set_xsync(info, (int)arg);
990 	case MGSL_IOCGXCTRL:
991 		return get_xctrl(info, argp);
992 	case MGSL_IOCSXCTRL:
993 		return set_xctrl(info, (int)arg);
994 	}
995 	mutex_lock(&info->port.mutex);
996 	switch (cmd) {
997 	case MGSL_IOCGPARAMS:
998 		ret = get_params(info, argp);
999 		break;
1000 	case MGSL_IOCSPARAMS:
1001 		ret = set_params(info, argp);
1002 		break;
1003 	case MGSL_IOCGTXIDLE:
1004 		ret = get_txidle(info, argp);
1005 		break;
1006 	case MGSL_IOCSTXIDLE:
1007 		ret = set_txidle(info, (int)arg);
1008 		break;
1009 	case MGSL_IOCTXENABLE:
1010 		ret = tx_enable(info, (int)arg);
1011 		break;
1012 	case MGSL_IOCRXENABLE:
1013 		ret = rx_enable(info, (int)arg);
1014 		break;
1015 	case MGSL_IOCTXABORT:
1016 		ret = tx_abort(info);
1017 		break;
1018 	case MGSL_IOCGSTATS:
1019 		ret = get_stats(info, argp);
1020 		break;
1021 	case MGSL_IOCGIF:
1022 		ret = get_interface(info, argp);
1023 		break;
1024 	case MGSL_IOCSIF:
1025 		ret = set_interface(info,(int)arg);
1026 		break;
1027 	default:
1028 		ret = -ENOIOCTLCMD;
1029 	}
1030 	mutex_unlock(&info->port.mutex);
1031 	return ret;
1032 }
1033 
1034 static int get_icount(struct tty_struct *tty,
1035 				struct serial_icounter_struct *icount)
1036 
1037 {
1038 	struct slgt_info *info = tty->driver_data;
1039 	struct mgsl_icount cnow;	/* kernel counter temps */
1040 	unsigned long flags;
1041 
1042 	spin_lock_irqsave(&info->lock,flags);
1043 	cnow = info->icount;
1044 	spin_unlock_irqrestore(&info->lock,flags);
1045 
1046 	icount->cts = cnow.cts;
1047 	icount->dsr = cnow.dsr;
1048 	icount->rng = cnow.rng;
1049 	icount->dcd = cnow.dcd;
1050 	icount->rx = cnow.rx;
1051 	icount->tx = cnow.tx;
1052 	icount->frame = cnow.frame;
1053 	icount->overrun = cnow.overrun;
1054 	icount->parity = cnow.parity;
1055 	icount->brk = cnow.brk;
1056 	icount->buf_overrun = cnow.buf_overrun;
1057 
1058 	return 0;
1059 }
1060 
1061 /*
1062  * support for 32 bit ioctl calls on 64 bit systems
1063  */
1064 #ifdef CONFIG_COMPAT
1065 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1066 {
1067 	struct MGSL_PARAMS32 tmp_params;
1068 
1069 	DBGINFO(("%s get_params32\n", info->device_name));
1070 	memset(&tmp_params, 0, sizeof(tmp_params));
1071 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1072 	tmp_params.loopback        = info->params.loopback;
1073 	tmp_params.flags           = info->params.flags;
1074 	tmp_params.encoding        = info->params.encoding;
1075 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1076 	tmp_params.addr_filter     = info->params.addr_filter;
1077 	tmp_params.crc_type        = info->params.crc_type;
1078 	tmp_params.preamble_length = info->params.preamble_length;
1079 	tmp_params.preamble        = info->params.preamble;
1080 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1081 	tmp_params.data_bits       = info->params.data_bits;
1082 	tmp_params.stop_bits       = info->params.stop_bits;
1083 	tmp_params.parity          = info->params.parity;
1084 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1085 		return -EFAULT;
1086 	return 0;
1087 }
1088 
1089 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1090 {
1091 	struct MGSL_PARAMS32 tmp_params;
1092 
1093 	DBGINFO(("%s set_params32\n", info->device_name));
1094 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1095 		return -EFAULT;
1096 
1097 	spin_lock(&info->lock);
1098 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1099 		info->base_clock = tmp_params.clock_speed;
1100 	} else {
1101 		info->params.mode            = tmp_params.mode;
1102 		info->params.loopback        = tmp_params.loopback;
1103 		info->params.flags           = tmp_params.flags;
1104 		info->params.encoding        = tmp_params.encoding;
1105 		info->params.clock_speed     = tmp_params.clock_speed;
1106 		info->params.addr_filter     = tmp_params.addr_filter;
1107 		info->params.crc_type        = tmp_params.crc_type;
1108 		info->params.preamble_length = tmp_params.preamble_length;
1109 		info->params.preamble        = tmp_params.preamble;
1110 		info->params.data_rate       = tmp_params.data_rate;
1111 		info->params.data_bits       = tmp_params.data_bits;
1112 		info->params.stop_bits       = tmp_params.stop_bits;
1113 		info->params.parity          = tmp_params.parity;
1114 	}
1115 	spin_unlock(&info->lock);
1116 
1117 	program_hw(info);
1118 
1119 	return 0;
1120 }
1121 
1122 static long slgt_compat_ioctl(struct tty_struct *tty,
1123 			 unsigned int cmd, unsigned long arg)
1124 {
1125 	struct slgt_info *info = tty->driver_data;
1126 	int rc;
1127 
1128 	if (sanity_check(info, tty->name, "compat_ioctl"))
1129 		return -ENODEV;
1130 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1131 
1132 	switch (cmd) {
1133 	case MGSL_IOCSPARAMS32:
1134 		rc = set_params32(info, compat_ptr(arg));
1135 		break;
1136 
1137 	case MGSL_IOCGPARAMS32:
1138 		rc = get_params32(info, compat_ptr(arg));
1139 		break;
1140 
1141 	case MGSL_IOCGPARAMS:
1142 	case MGSL_IOCSPARAMS:
1143 	case MGSL_IOCGTXIDLE:
1144 	case MGSL_IOCGSTATS:
1145 	case MGSL_IOCWAITEVENT:
1146 	case MGSL_IOCGIF:
1147 	case MGSL_IOCSGPIO:
1148 	case MGSL_IOCGGPIO:
1149 	case MGSL_IOCWAITGPIO:
1150 	case MGSL_IOCGXSYNC:
1151 	case MGSL_IOCGXCTRL:
1152 		rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1153 		break;
1154 	default:
1155 		rc = ioctl(tty, cmd, arg);
1156 	}
1157 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1158 	return rc;
1159 }
1160 #else
1161 #define slgt_compat_ioctl NULL
1162 #endif /* ifdef CONFIG_COMPAT */
1163 
1164 /*
1165  * proc fs support
1166  */
1167 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1168 {
1169 	char stat_buf[30];
1170 	unsigned long flags;
1171 
1172 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1173 		      info->device_name, info->phys_reg_addr,
1174 		      info->irq_level, info->max_frame_size);
1175 
1176 	/* output current serial signal states */
1177 	spin_lock_irqsave(&info->lock,flags);
1178 	get_gtsignals(info);
1179 	spin_unlock_irqrestore(&info->lock,flags);
1180 
1181 	stat_buf[0] = 0;
1182 	stat_buf[1] = 0;
1183 	if (info->signals & SerialSignal_RTS)
1184 		strcat(stat_buf, "|RTS");
1185 	if (info->signals & SerialSignal_CTS)
1186 		strcat(stat_buf, "|CTS");
1187 	if (info->signals & SerialSignal_DTR)
1188 		strcat(stat_buf, "|DTR");
1189 	if (info->signals & SerialSignal_DSR)
1190 		strcat(stat_buf, "|DSR");
1191 	if (info->signals & SerialSignal_DCD)
1192 		strcat(stat_buf, "|CD");
1193 	if (info->signals & SerialSignal_RI)
1194 		strcat(stat_buf, "|RI");
1195 
1196 	if (info->params.mode != MGSL_MODE_ASYNC) {
1197 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1198 			       info->icount.txok, info->icount.rxok);
1199 		if (info->icount.txunder)
1200 			seq_printf(m, " txunder:%d", info->icount.txunder);
1201 		if (info->icount.txabort)
1202 			seq_printf(m, " txabort:%d", info->icount.txabort);
1203 		if (info->icount.rxshort)
1204 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1205 		if (info->icount.rxlong)
1206 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1207 		if (info->icount.rxover)
1208 			seq_printf(m, " rxover:%d", info->icount.rxover);
1209 		if (info->icount.rxcrc)
1210 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1211 	} else {
1212 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1213 			       info->icount.tx, info->icount.rx);
1214 		if (info->icount.frame)
1215 			seq_printf(m, " fe:%d", info->icount.frame);
1216 		if (info->icount.parity)
1217 			seq_printf(m, " pe:%d", info->icount.parity);
1218 		if (info->icount.brk)
1219 			seq_printf(m, " brk:%d", info->icount.brk);
1220 		if (info->icount.overrun)
1221 			seq_printf(m, " oe:%d", info->icount.overrun);
1222 	}
1223 
1224 	/* Append serial signal status to end */
1225 	seq_printf(m, " %s\n", stat_buf+1);
1226 
1227 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1228 		       info->tx_active,info->bh_requested,info->bh_running,
1229 		       info->pending_bh);
1230 }
1231 
1232 /* Called to print information about devices
1233  */
1234 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1235 {
1236 	struct slgt_info *info;
1237 
1238 	seq_puts(m, "synclink_gt driver\n");
1239 
1240 	info = slgt_device_list;
1241 	while( info ) {
1242 		line_info(m, info);
1243 		info = info->next_device;
1244 	}
1245 	return 0;
1246 }
1247 
1248 /*
1249  * return count of bytes in transmit buffer
1250  */
1251 static unsigned int chars_in_buffer(struct tty_struct *tty)
1252 {
1253 	struct slgt_info *info = tty->driver_data;
1254 	unsigned int count;
1255 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1256 		return 0;
1257 	count = tbuf_bytes(info);
1258 	DBGINFO(("%s chars_in_buffer()=%u\n", info->device_name, count));
1259 	return count;
1260 }
1261 
1262 /*
1263  * signal remote device to throttle send data (our receive data)
1264  */
1265 static void throttle(struct tty_struct * tty)
1266 {
1267 	struct slgt_info *info = tty->driver_data;
1268 	unsigned long flags;
1269 
1270 	if (sanity_check(info, tty->name, "throttle"))
1271 		return;
1272 	DBGINFO(("%s throttle\n", info->device_name));
1273 	if (I_IXOFF(tty))
1274 		send_xchar(tty, STOP_CHAR(tty));
1275 	if (C_CRTSCTS(tty)) {
1276 		spin_lock_irqsave(&info->lock,flags);
1277 		info->signals &= ~SerialSignal_RTS;
1278 		set_gtsignals(info);
1279 		spin_unlock_irqrestore(&info->lock,flags);
1280 	}
1281 }
1282 
1283 /*
1284  * signal remote device to stop throttling send data (our receive data)
1285  */
1286 static void unthrottle(struct tty_struct * tty)
1287 {
1288 	struct slgt_info *info = tty->driver_data;
1289 	unsigned long flags;
1290 
1291 	if (sanity_check(info, tty->name, "unthrottle"))
1292 		return;
1293 	DBGINFO(("%s unthrottle\n", info->device_name));
1294 	if (I_IXOFF(tty)) {
1295 		if (info->x_char)
1296 			info->x_char = 0;
1297 		else
1298 			send_xchar(tty, START_CHAR(tty));
1299 	}
1300 	if (C_CRTSCTS(tty)) {
1301 		spin_lock_irqsave(&info->lock,flags);
1302 		info->signals |= SerialSignal_RTS;
1303 		set_gtsignals(info);
1304 		spin_unlock_irqrestore(&info->lock,flags);
1305 	}
1306 }
1307 
1308 /*
1309  * set or clear transmit break condition
1310  * break_state	-1=set break condition, 0=clear
1311  */
1312 static int set_break(struct tty_struct *tty, int break_state)
1313 {
1314 	struct slgt_info *info = tty->driver_data;
1315 	unsigned short value;
1316 	unsigned long flags;
1317 
1318 	if (sanity_check(info, tty->name, "set_break"))
1319 		return -EINVAL;
1320 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1321 
1322 	spin_lock_irqsave(&info->lock,flags);
1323 	value = rd_reg16(info, TCR);
1324  	if (break_state == -1)
1325 		value |= BIT6;
1326 	else
1327 		value &= ~BIT6;
1328 	wr_reg16(info, TCR, value);
1329 	spin_unlock_irqrestore(&info->lock,flags);
1330 	return 0;
1331 }
1332 
1333 #if SYNCLINK_GENERIC_HDLC
1334 
1335 /**
1336  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1337  * @dev:      pointer to network device structure
1338  * @encoding: serial encoding setting
1339  * @parity:   FCS setting
1340  *
1341  * Set encoding and frame check sequence (FCS) options.
1342  *
1343  * Return: 0 if success, otherwise error code
1344  */
1345 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1346 			  unsigned short parity)
1347 {
1348 	struct slgt_info *info = dev_to_port(dev);
1349 	unsigned char  new_encoding;
1350 	unsigned short new_crctype;
1351 
1352 	/* return error if TTY interface open */
1353 	if (info->port.count)
1354 		return -EBUSY;
1355 
1356 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1357 
1358 	switch (encoding)
1359 	{
1360 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1361 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1362 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1363 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1364 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1365 	default: return -EINVAL;
1366 	}
1367 
1368 	switch (parity)
1369 	{
1370 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1371 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1372 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1373 	default: return -EINVAL;
1374 	}
1375 
1376 	info->params.encoding = new_encoding;
1377 	info->params.crc_type = new_crctype;
1378 
1379 	/* if network interface up, reprogram hardware */
1380 	if (info->netcount)
1381 		program_hw(info);
1382 
1383 	return 0;
1384 }
1385 
1386 /**
1387  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1388  * @skb: socket buffer containing HDLC frame
1389  * @dev: pointer to network device structure
1390  */
1391 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1392 				      struct net_device *dev)
1393 {
1394 	struct slgt_info *info = dev_to_port(dev);
1395 	unsigned long flags;
1396 
1397 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1398 
1399 	if (!skb->len)
1400 		return NETDEV_TX_OK;
1401 
1402 	/* stop sending until this frame completes */
1403 	netif_stop_queue(dev);
1404 
1405 	/* update network statistics */
1406 	dev->stats.tx_packets++;
1407 	dev->stats.tx_bytes += skb->len;
1408 
1409 	/* save start time for transmit timeout detection */
1410 	netif_trans_update(dev);
1411 
1412 	spin_lock_irqsave(&info->lock, flags);
1413 	tx_load(info, skb->data, skb->len);
1414 	spin_unlock_irqrestore(&info->lock, flags);
1415 
1416 	/* done with socket buffer, so free it */
1417 	dev_kfree_skb(skb);
1418 
1419 	return NETDEV_TX_OK;
1420 }
1421 
1422 /**
1423  * hdlcdev_open - called by network layer when interface enabled
1424  * @dev: pointer to network device structure
1425  *
1426  * Claim resources and initialize hardware.
1427  *
1428  * Return: 0 if success, otherwise error code
1429  */
1430 static int hdlcdev_open(struct net_device *dev)
1431 {
1432 	struct slgt_info *info = dev_to_port(dev);
1433 	int rc;
1434 	unsigned long flags;
1435 
1436 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1437 
1438 	/* arbitrate between network and tty opens */
1439 	spin_lock_irqsave(&info->netlock, flags);
1440 	if (info->port.count != 0 || info->netcount != 0) {
1441 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1442 		spin_unlock_irqrestore(&info->netlock, flags);
1443 		return -EBUSY;
1444 	}
1445 	info->netcount=1;
1446 	spin_unlock_irqrestore(&info->netlock, flags);
1447 
1448 	/* claim resources and init adapter */
1449 	if ((rc = startup(info)) != 0) {
1450 		spin_lock_irqsave(&info->netlock, flags);
1451 		info->netcount=0;
1452 		spin_unlock_irqrestore(&info->netlock, flags);
1453 		return rc;
1454 	}
1455 
1456 	/* generic HDLC layer open processing */
1457 	rc = hdlc_open(dev);
1458 	if (rc) {
1459 		shutdown(info);
1460 		spin_lock_irqsave(&info->netlock, flags);
1461 		info->netcount = 0;
1462 		spin_unlock_irqrestore(&info->netlock, flags);
1463 		return rc;
1464 	}
1465 
1466 	/* assert RTS and DTR, apply hardware settings */
1467 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1468 	program_hw(info);
1469 
1470 	/* enable network layer transmit */
1471 	netif_trans_update(dev);
1472 	netif_start_queue(dev);
1473 
1474 	/* inform generic HDLC layer of current DCD status */
1475 	spin_lock_irqsave(&info->lock, flags);
1476 	get_gtsignals(info);
1477 	spin_unlock_irqrestore(&info->lock, flags);
1478 	if (info->signals & SerialSignal_DCD)
1479 		netif_carrier_on(dev);
1480 	else
1481 		netif_carrier_off(dev);
1482 	return 0;
1483 }
1484 
1485 /**
1486  * hdlcdev_close - called by network layer when interface is disabled
1487  * @dev:  pointer to network device structure
1488  *
1489  * Shutdown hardware and release resources.
1490  *
1491  * Return: 0 if success, otherwise error code
1492  */
1493 static int hdlcdev_close(struct net_device *dev)
1494 {
1495 	struct slgt_info *info = dev_to_port(dev);
1496 	unsigned long flags;
1497 
1498 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1499 
1500 	netif_stop_queue(dev);
1501 
1502 	/* shutdown adapter and release resources */
1503 	shutdown(info);
1504 
1505 	hdlc_close(dev);
1506 
1507 	spin_lock_irqsave(&info->netlock, flags);
1508 	info->netcount=0;
1509 	spin_unlock_irqrestore(&info->netlock, flags);
1510 
1511 	return 0;
1512 }
1513 
1514 /**
1515  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1516  * @dev: pointer to network device structure
1517  * @ifr: pointer to network interface request structure
1518  * @cmd: IOCTL command code
1519  *
1520  * Return: 0 if success, otherwise error code
1521  */
1522 static int hdlcdev_ioctl(struct net_device *dev, struct if_settings *ifs)
1523 {
1524 	const size_t size = sizeof(sync_serial_settings);
1525 	sync_serial_settings new_line;
1526 	sync_serial_settings __user *line = ifs->ifs_ifsu.sync;
1527 	struct slgt_info *info = dev_to_port(dev);
1528 	unsigned int flags;
1529 
1530 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1531 
1532 	/* return error if TTY interface open */
1533 	if (info->port.count)
1534 		return -EBUSY;
1535 
1536 	memset(&new_line, 0, sizeof(new_line));
1537 
1538 	switch (ifs->type) {
1539 	case IF_GET_IFACE: /* return current sync_serial_settings */
1540 
1541 		ifs->type = IF_IFACE_SYNC_SERIAL;
1542 		if (ifs->size < size) {
1543 			ifs->size = size; /* data size wanted */
1544 			return -ENOBUFS;
1545 		}
1546 
1547 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1548 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1549 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1550 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1551 
1552 		switch (flags){
1553 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1554 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1555 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1556 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1557 		default: new_line.clock_type = CLOCK_DEFAULT;
1558 		}
1559 
1560 		new_line.clock_rate = info->params.clock_speed;
1561 		new_line.loopback   = info->params.loopback ? 1:0;
1562 
1563 		if (copy_to_user(line, &new_line, size))
1564 			return -EFAULT;
1565 		return 0;
1566 
1567 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1568 
1569 		if(!capable(CAP_NET_ADMIN))
1570 			return -EPERM;
1571 		if (copy_from_user(&new_line, line, size))
1572 			return -EFAULT;
1573 
1574 		switch (new_line.clock_type)
1575 		{
1576 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1577 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1578 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1579 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1580 		case CLOCK_DEFAULT:  flags = info->params.flags &
1581 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1582 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1583 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1584 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1585 		default: return -EINVAL;
1586 		}
1587 
1588 		if (new_line.loopback != 0 && new_line.loopback != 1)
1589 			return -EINVAL;
1590 
1591 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1592 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1593 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1594 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1595 		info->params.flags |= flags;
1596 
1597 		info->params.loopback = new_line.loopback;
1598 
1599 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1600 			info->params.clock_speed = new_line.clock_rate;
1601 		else
1602 			info->params.clock_speed = 0;
1603 
1604 		/* if network interface up, reprogram hardware */
1605 		if (info->netcount)
1606 			program_hw(info);
1607 		return 0;
1608 
1609 	default:
1610 		return hdlc_ioctl(dev, ifs);
1611 	}
1612 }
1613 
1614 /**
1615  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1616  * @dev: pointer to network device structure
1617  * @txqueue: unused
1618  */
1619 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1620 {
1621 	struct slgt_info *info = dev_to_port(dev);
1622 	unsigned long flags;
1623 
1624 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1625 
1626 	dev->stats.tx_errors++;
1627 	dev->stats.tx_aborted_errors++;
1628 
1629 	spin_lock_irqsave(&info->lock,flags);
1630 	tx_stop(info);
1631 	spin_unlock_irqrestore(&info->lock,flags);
1632 
1633 	netif_wake_queue(dev);
1634 }
1635 
1636 /**
1637  * hdlcdev_tx_done - called by device driver when transmit completes
1638  * @info: pointer to device instance information
1639  *
1640  * Reenable network layer transmit if stopped.
1641  */
1642 static void hdlcdev_tx_done(struct slgt_info *info)
1643 {
1644 	if (netif_queue_stopped(info->netdev))
1645 		netif_wake_queue(info->netdev);
1646 }
1647 
1648 /**
1649  * hdlcdev_rx - called by device driver when frame received
1650  * @info: pointer to device instance information
1651  * @buf:  pointer to buffer contianing frame data
1652  * @size: count of data bytes in buf
1653  *
1654  * Pass frame to network layer.
1655  */
1656 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1657 {
1658 	struct sk_buff *skb = dev_alloc_skb(size);
1659 	struct net_device *dev = info->netdev;
1660 
1661 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1662 
1663 	if (skb == NULL) {
1664 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1665 		dev->stats.rx_dropped++;
1666 		return;
1667 	}
1668 
1669 	skb_put_data(skb, buf, size);
1670 
1671 	skb->protocol = hdlc_type_trans(skb, dev);
1672 
1673 	dev->stats.rx_packets++;
1674 	dev->stats.rx_bytes += size;
1675 
1676 	netif_rx(skb);
1677 }
1678 
1679 static const struct net_device_ops hdlcdev_ops = {
1680 	.ndo_open       = hdlcdev_open,
1681 	.ndo_stop       = hdlcdev_close,
1682 	.ndo_start_xmit = hdlc_start_xmit,
1683 	.ndo_siocwandev = hdlcdev_ioctl,
1684 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1685 };
1686 
1687 /**
1688  * hdlcdev_init - called by device driver when adding device instance
1689  * @info: pointer to device instance information
1690  *
1691  * Do generic HDLC initialization.
1692  *
1693  * Return: 0 if success, otherwise error code
1694  */
1695 static int hdlcdev_init(struct slgt_info *info)
1696 {
1697 	int rc;
1698 	struct net_device *dev;
1699 	hdlc_device *hdlc;
1700 
1701 	/* allocate and initialize network and HDLC layer objects */
1702 
1703 	dev = alloc_hdlcdev(info);
1704 	if (!dev) {
1705 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1706 		return -ENOMEM;
1707 	}
1708 
1709 	/* for network layer reporting purposes only */
1710 	dev->mem_start = info->phys_reg_addr;
1711 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1712 	dev->irq       = info->irq_level;
1713 
1714 	/* network layer callbacks and settings */
1715 	dev->netdev_ops	    = &hdlcdev_ops;
1716 	dev->watchdog_timeo = 10 * HZ;
1717 	dev->tx_queue_len   = 50;
1718 
1719 	/* generic HDLC layer callbacks and settings */
1720 	hdlc         = dev_to_hdlc(dev);
1721 	hdlc->attach = hdlcdev_attach;
1722 	hdlc->xmit   = hdlcdev_xmit;
1723 
1724 	/* register objects with HDLC layer */
1725 	rc = register_hdlc_device(dev);
1726 	if (rc) {
1727 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1728 		free_netdev(dev);
1729 		return rc;
1730 	}
1731 
1732 	info->netdev = dev;
1733 	return 0;
1734 }
1735 
1736 /**
1737  * hdlcdev_exit - called by device driver when removing device instance
1738  * @info: pointer to device instance information
1739  *
1740  * Do generic HDLC cleanup.
1741  */
1742 static void hdlcdev_exit(struct slgt_info *info)
1743 {
1744 	if (!info->netdev)
1745 		return;
1746 	unregister_hdlc_device(info->netdev);
1747 	free_netdev(info->netdev);
1748 	info->netdev = NULL;
1749 }
1750 
1751 #endif /* ifdef CONFIG_HDLC */
1752 
1753 /*
1754  * get async data from rx DMA buffers
1755  */
1756 static void rx_async(struct slgt_info *info)
1757 {
1758  	struct mgsl_icount *icount = &info->icount;
1759 	unsigned int start, end;
1760 	unsigned char *p;
1761 	unsigned char status;
1762 	struct slgt_desc *bufs = info->rbufs;
1763 	int i, count;
1764 	int chars = 0;
1765 	int stat;
1766 	unsigned char ch;
1767 
1768 	start = end = info->rbuf_current;
1769 
1770 	while(desc_complete(bufs[end])) {
1771 		count = desc_count(bufs[end]) - info->rbuf_index;
1772 		p     = bufs[end].buf + info->rbuf_index;
1773 
1774 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1775 		DBGDATA(info, p, count, "rx");
1776 
1777 		for(i=0 ; i < count; i+=2, p+=2) {
1778 			ch = *p;
1779 			icount->rx++;
1780 
1781 			stat = 0;
1782 
1783 			status = *(p + 1) & (BIT1 + BIT0);
1784 			if (status) {
1785 				if (status & BIT1)
1786 					icount->parity++;
1787 				else if (status & BIT0)
1788 					icount->frame++;
1789 				/* discard char if tty control flags say so */
1790 				if (status & info->ignore_status_mask)
1791 					continue;
1792 				if (status & BIT1)
1793 					stat = TTY_PARITY;
1794 				else if (status & BIT0)
1795 					stat = TTY_FRAME;
1796 			}
1797 			tty_insert_flip_char(&info->port, ch, stat);
1798 			chars++;
1799 		}
1800 
1801 		if (i < count) {
1802 			/* receive buffer not completed */
1803 			info->rbuf_index += i;
1804 			mod_timer(&info->rx_timer, jiffies + 1);
1805 			break;
1806 		}
1807 
1808 		info->rbuf_index = 0;
1809 		free_rbufs(info, end, end);
1810 
1811 		if (++end == info->rbuf_count)
1812 			end = 0;
1813 
1814 		/* if entire list searched then no frame available */
1815 		if (end == start)
1816 			break;
1817 	}
1818 
1819 	if (chars)
1820 		tty_flip_buffer_push(&info->port);
1821 }
1822 
1823 /*
1824  * return next bottom half action to perform
1825  */
1826 static int bh_action(struct slgt_info *info)
1827 {
1828 	unsigned long flags;
1829 	int rc;
1830 
1831 	spin_lock_irqsave(&info->lock,flags);
1832 
1833 	if (info->pending_bh & BH_RECEIVE) {
1834 		info->pending_bh &= ~BH_RECEIVE;
1835 		rc = BH_RECEIVE;
1836 	} else if (info->pending_bh & BH_TRANSMIT) {
1837 		info->pending_bh &= ~BH_TRANSMIT;
1838 		rc = BH_TRANSMIT;
1839 	} else if (info->pending_bh & BH_STATUS) {
1840 		info->pending_bh &= ~BH_STATUS;
1841 		rc = BH_STATUS;
1842 	} else {
1843 		/* Mark BH routine as complete */
1844 		info->bh_running = false;
1845 		info->bh_requested = false;
1846 		rc = 0;
1847 	}
1848 
1849 	spin_unlock_irqrestore(&info->lock,flags);
1850 
1851 	return rc;
1852 }
1853 
1854 /*
1855  * perform bottom half processing
1856  */
1857 static void bh_handler(struct work_struct *work)
1858 {
1859 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1860 	int action;
1861 
1862 	info->bh_running = true;
1863 
1864 	while((action = bh_action(info))) {
1865 		switch (action) {
1866 		case BH_RECEIVE:
1867 			DBGBH(("%s bh receive\n", info->device_name));
1868 			switch(info->params.mode) {
1869 			case MGSL_MODE_ASYNC:
1870 				rx_async(info);
1871 				break;
1872 			case MGSL_MODE_HDLC:
1873 				while(rx_get_frame(info));
1874 				break;
1875 			case MGSL_MODE_RAW:
1876 			case MGSL_MODE_MONOSYNC:
1877 			case MGSL_MODE_BISYNC:
1878 			case MGSL_MODE_XSYNC:
1879 				while(rx_get_buf(info));
1880 				break;
1881 			}
1882 			/* restart receiver if rx DMA buffers exhausted */
1883 			if (info->rx_restart)
1884 				rx_start(info);
1885 			break;
1886 		case BH_TRANSMIT:
1887 			bh_transmit(info);
1888 			break;
1889 		case BH_STATUS:
1890 			DBGBH(("%s bh status\n", info->device_name));
1891 			info->ri_chkcount = 0;
1892 			info->dsr_chkcount = 0;
1893 			info->dcd_chkcount = 0;
1894 			info->cts_chkcount = 0;
1895 			break;
1896 		default:
1897 			DBGBH(("%s unknown action\n", info->device_name));
1898 			break;
1899 		}
1900 	}
1901 	DBGBH(("%s bh_handler exit\n", info->device_name));
1902 }
1903 
1904 static void bh_transmit(struct slgt_info *info)
1905 {
1906 	struct tty_struct *tty = info->port.tty;
1907 
1908 	DBGBH(("%s bh_transmit\n", info->device_name));
1909 	if (tty)
1910 		tty_wakeup(tty);
1911 }
1912 
1913 static void dsr_change(struct slgt_info *info, unsigned short status)
1914 {
1915 	if (status & BIT3) {
1916 		info->signals |= SerialSignal_DSR;
1917 		info->input_signal_events.dsr_up++;
1918 	} else {
1919 		info->signals &= ~SerialSignal_DSR;
1920 		info->input_signal_events.dsr_down++;
1921 	}
1922 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1923 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1924 		slgt_irq_off(info, IRQ_DSR);
1925 		return;
1926 	}
1927 	info->icount.dsr++;
1928 	wake_up_interruptible(&info->status_event_wait_q);
1929 	wake_up_interruptible(&info->event_wait_q);
1930 	info->pending_bh |= BH_STATUS;
1931 }
1932 
1933 static void cts_change(struct slgt_info *info, unsigned short status)
1934 {
1935 	if (status & BIT2) {
1936 		info->signals |= SerialSignal_CTS;
1937 		info->input_signal_events.cts_up++;
1938 	} else {
1939 		info->signals &= ~SerialSignal_CTS;
1940 		info->input_signal_events.cts_down++;
1941 	}
1942 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1943 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1944 		slgt_irq_off(info, IRQ_CTS);
1945 		return;
1946 	}
1947 	info->icount.cts++;
1948 	wake_up_interruptible(&info->status_event_wait_q);
1949 	wake_up_interruptible(&info->event_wait_q);
1950 	info->pending_bh |= BH_STATUS;
1951 
1952 	if (tty_port_cts_enabled(&info->port)) {
1953 		if (info->port.tty) {
1954 			if (info->port.tty->hw_stopped) {
1955 				if (info->signals & SerialSignal_CTS) {
1956 		 			info->port.tty->hw_stopped = 0;
1957 					info->pending_bh |= BH_TRANSMIT;
1958 					return;
1959 				}
1960 			} else {
1961 				if (!(info->signals & SerialSignal_CTS))
1962 		 			info->port.tty->hw_stopped = 1;
1963 			}
1964 		}
1965 	}
1966 }
1967 
1968 static void dcd_change(struct slgt_info *info, unsigned short status)
1969 {
1970 	if (status & BIT1) {
1971 		info->signals |= SerialSignal_DCD;
1972 		info->input_signal_events.dcd_up++;
1973 	} else {
1974 		info->signals &= ~SerialSignal_DCD;
1975 		info->input_signal_events.dcd_down++;
1976 	}
1977 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1978 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1979 		slgt_irq_off(info, IRQ_DCD);
1980 		return;
1981 	}
1982 	info->icount.dcd++;
1983 #if SYNCLINK_GENERIC_HDLC
1984 	if (info->netcount) {
1985 		if (info->signals & SerialSignal_DCD)
1986 			netif_carrier_on(info->netdev);
1987 		else
1988 			netif_carrier_off(info->netdev);
1989 	}
1990 #endif
1991 	wake_up_interruptible(&info->status_event_wait_q);
1992 	wake_up_interruptible(&info->event_wait_q);
1993 	info->pending_bh |= BH_STATUS;
1994 
1995 	if (tty_port_check_carrier(&info->port)) {
1996 		if (info->signals & SerialSignal_DCD)
1997 			wake_up_interruptible(&info->port.open_wait);
1998 		else {
1999 			if (info->port.tty)
2000 				tty_hangup(info->port.tty);
2001 		}
2002 	}
2003 }
2004 
2005 static void ri_change(struct slgt_info *info, unsigned short status)
2006 {
2007 	if (status & BIT0) {
2008 		info->signals |= SerialSignal_RI;
2009 		info->input_signal_events.ri_up++;
2010 	} else {
2011 		info->signals &= ~SerialSignal_RI;
2012 		info->input_signal_events.ri_down++;
2013 	}
2014 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2015 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2016 		slgt_irq_off(info, IRQ_RI);
2017 		return;
2018 	}
2019 	info->icount.rng++;
2020 	wake_up_interruptible(&info->status_event_wait_q);
2021 	wake_up_interruptible(&info->event_wait_q);
2022 	info->pending_bh |= BH_STATUS;
2023 }
2024 
2025 static void isr_rxdata(struct slgt_info *info)
2026 {
2027 	unsigned int count = info->rbuf_fill_count;
2028 	unsigned int i = info->rbuf_fill_index;
2029 	unsigned short reg;
2030 
2031 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2032 		reg = rd_reg16(info, RDR);
2033 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2034 		if (desc_complete(info->rbufs[i])) {
2035 			/* all buffers full */
2036 			rx_stop(info);
2037 			info->rx_restart = true;
2038 			continue;
2039 		}
2040 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2041 		/* async mode saves status byte to buffer for each data byte */
2042 		if (info->params.mode == MGSL_MODE_ASYNC)
2043 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2044 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2045 			/* buffer full or end of frame */
2046 			set_desc_count(info->rbufs[i], count);
2047 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2048 			info->rbuf_fill_count = count = 0;
2049 			if (++i == info->rbuf_count)
2050 				i = 0;
2051 			info->pending_bh |= BH_RECEIVE;
2052 		}
2053 	}
2054 
2055 	info->rbuf_fill_index = i;
2056 	info->rbuf_fill_count = count;
2057 }
2058 
2059 static void isr_serial(struct slgt_info *info)
2060 {
2061 	unsigned short status = rd_reg16(info, SSR);
2062 
2063 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2064 
2065 	wr_reg16(info, SSR, status); /* clear pending */
2066 
2067 	info->irq_occurred = true;
2068 
2069 	if (info->params.mode == MGSL_MODE_ASYNC) {
2070 		if (status & IRQ_TXIDLE) {
2071 			if (info->tx_active)
2072 				isr_txeom(info, status);
2073 		}
2074 		if (info->rx_pio && (status & IRQ_RXDATA))
2075 			isr_rxdata(info);
2076 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2077 			info->icount.brk++;
2078 			/* process break detection if tty control allows */
2079 			if (info->port.tty) {
2080 				if (!(status & info->ignore_status_mask)) {
2081 					if (info->read_status_mask & MASK_BREAK) {
2082 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2083 						if (info->port.flags & ASYNC_SAK)
2084 							do_SAK(info->port.tty);
2085 					}
2086 				}
2087 			}
2088 		}
2089 	} else {
2090 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2091 			isr_txeom(info, status);
2092 		if (info->rx_pio && (status & IRQ_RXDATA))
2093 			isr_rxdata(info);
2094 		if (status & IRQ_RXIDLE) {
2095 			if (status & RXIDLE)
2096 				info->icount.rxidle++;
2097 			else
2098 				info->icount.exithunt++;
2099 			wake_up_interruptible(&info->event_wait_q);
2100 		}
2101 
2102 		if (status & IRQ_RXOVER)
2103 			rx_start(info);
2104 	}
2105 
2106 	if (status & IRQ_DSR)
2107 		dsr_change(info, status);
2108 	if (status & IRQ_CTS)
2109 		cts_change(info, status);
2110 	if (status & IRQ_DCD)
2111 		dcd_change(info, status);
2112 	if (status & IRQ_RI)
2113 		ri_change(info, status);
2114 }
2115 
2116 static void isr_rdma(struct slgt_info *info)
2117 {
2118 	unsigned int status = rd_reg32(info, RDCSR);
2119 
2120 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2121 
2122 	/* RDCSR (rx DMA control/status)
2123 	 *
2124 	 * 31..07  reserved
2125 	 * 06      save status byte to DMA buffer
2126 	 * 05      error
2127 	 * 04      eol (end of list)
2128 	 * 03      eob (end of buffer)
2129 	 * 02      IRQ enable
2130 	 * 01      reset
2131 	 * 00      enable
2132 	 */
2133 	wr_reg32(info, RDCSR, status);	/* clear pending */
2134 
2135 	if (status & (BIT5 + BIT4)) {
2136 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2137 		info->rx_restart = true;
2138 	}
2139 	info->pending_bh |= BH_RECEIVE;
2140 }
2141 
2142 static void isr_tdma(struct slgt_info *info)
2143 {
2144 	unsigned int status = rd_reg32(info, TDCSR);
2145 
2146 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2147 
2148 	/* TDCSR (tx DMA control/status)
2149 	 *
2150 	 * 31..06  reserved
2151 	 * 05      error
2152 	 * 04      eol (end of list)
2153 	 * 03      eob (end of buffer)
2154 	 * 02      IRQ enable
2155 	 * 01      reset
2156 	 * 00      enable
2157 	 */
2158 	wr_reg32(info, TDCSR, status);	/* clear pending */
2159 
2160 	if (status & (BIT5 + BIT4 + BIT3)) {
2161 		// another transmit buffer has completed
2162 		// run bottom half to get more send data from user
2163 		info->pending_bh |= BH_TRANSMIT;
2164 	}
2165 }
2166 
2167 /*
2168  * return true if there are unsent tx DMA buffers, otherwise false
2169  *
2170  * if there are unsent buffers then info->tbuf_start
2171  * is set to index of first unsent buffer
2172  */
2173 static bool unsent_tbufs(struct slgt_info *info)
2174 {
2175 	unsigned int i = info->tbuf_current;
2176 	bool rc = false;
2177 
2178 	/*
2179 	 * search backwards from last loaded buffer (precedes tbuf_current)
2180 	 * for first unsent buffer (desc_count > 0)
2181 	 */
2182 
2183 	do {
2184 		if (i)
2185 			i--;
2186 		else
2187 			i = info->tbuf_count - 1;
2188 		if (!desc_count(info->tbufs[i]))
2189 			break;
2190 		info->tbuf_start = i;
2191 		rc = true;
2192 	} while (i != info->tbuf_current);
2193 
2194 	return rc;
2195 }
2196 
2197 static void isr_txeom(struct slgt_info *info, unsigned short status)
2198 {
2199 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2200 
2201 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2202 	tdma_reset(info);
2203 	if (status & IRQ_TXUNDER) {
2204 		unsigned short val = rd_reg16(info, TCR);
2205 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2206 		wr_reg16(info, TCR, val); /* clear reset bit */
2207 	}
2208 
2209 	if (info->tx_active) {
2210 		if (info->params.mode != MGSL_MODE_ASYNC) {
2211 			if (status & IRQ_TXUNDER)
2212 				info->icount.txunder++;
2213 			else if (status & IRQ_TXIDLE)
2214 				info->icount.txok++;
2215 		}
2216 
2217 		if (unsent_tbufs(info)) {
2218 			tx_start(info);
2219 			update_tx_timer(info);
2220 			return;
2221 		}
2222 		info->tx_active = false;
2223 
2224 		del_timer(&info->tx_timer);
2225 
2226 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2227 			info->signals &= ~SerialSignal_RTS;
2228 			info->drop_rts_on_tx_done = false;
2229 			set_gtsignals(info);
2230 		}
2231 
2232 #if SYNCLINK_GENERIC_HDLC
2233 		if (info->netcount)
2234 			hdlcdev_tx_done(info);
2235 		else
2236 #endif
2237 		{
2238 			if (info->port.tty && (info->port.tty->flow.stopped || info->port.tty->hw_stopped)) {
2239 				tx_stop(info);
2240 				return;
2241 			}
2242 			info->pending_bh |= BH_TRANSMIT;
2243 		}
2244 	}
2245 }
2246 
2247 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2248 {
2249 	struct cond_wait *w, *prev;
2250 
2251 	/* wake processes waiting for specific transitions */
2252 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2253 		if (w->data & changed) {
2254 			w->data = state;
2255 			wake_up_interruptible(&w->q);
2256 			if (prev != NULL)
2257 				prev->next = w->next;
2258 			else
2259 				info->gpio_wait_q = w->next;
2260 		} else
2261 			prev = w;
2262 	}
2263 }
2264 
2265 /* interrupt service routine
2266  *
2267  * 	irq	interrupt number
2268  * 	dev_id	device ID supplied during interrupt registration
2269  */
2270 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2271 {
2272 	struct slgt_info *info = dev_id;
2273 	unsigned int gsr;
2274 	unsigned int i;
2275 
2276 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2277 
2278 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2279 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2280 		info->irq_occurred = true;
2281 		for(i=0; i < info->port_count ; i++) {
2282 			if (info->port_array[i] == NULL)
2283 				continue;
2284 			spin_lock(&info->port_array[i]->lock);
2285 			if (gsr & (BIT8 << i))
2286 				isr_serial(info->port_array[i]);
2287 			if (gsr & (BIT16 << (i*2)))
2288 				isr_rdma(info->port_array[i]);
2289 			if (gsr & (BIT17 << (i*2)))
2290 				isr_tdma(info->port_array[i]);
2291 			spin_unlock(&info->port_array[i]->lock);
2292 		}
2293 	}
2294 
2295 	if (info->gpio_present) {
2296 		unsigned int state;
2297 		unsigned int changed;
2298 		spin_lock(&info->lock);
2299 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2300 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2301 			/* read latched state of GPIO signals */
2302 			state = rd_reg32(info, IOVR);
2303 			/* clear pending GPIO interrupt bits */
2304 			wr_reg32(info, IOSR, changed);
2305 			for (i=0 ; i < info->port_count ; i++) {
2306 				if (info->port_array[i] != NULL)
2307 					isr_gpio(info->port_array[i], changed, state);
2308 			}
2309 		}
2310 		spin_unlock(&info->lock);
2311 	}
2312 
2313 	for(i=0; i < info->port_count ; i++) {
2314 		struct slgt_info *port = info->port_array[i];
2315 		if (port == NULL)
2316 			continue;
2317 		spin_lock(&port->lock);
2318 		if ((port->port.count || port->netcount) &&
2319 		    port->pending_bh && !port->bh_running &&
2320 		    !port->bh_requested) {
2321 			DBGISR(("%s bh queued\n", port->device_name));
2322 			schedule_work(&port->task);
2323 			port->bh_requested = true;
2324 		}
2325 		spin_unlock(&port->lock);
2326 	}
2327 
2328 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2329 	return IRQ_HANDLED;
2330 }
2331 
2332 static int startup(struct slgt_info *info)
2333 {
2334 	DBGINFO(("%s startup\n", info->device_name));
2335 
2336 	if (tty_port_initialized(&info->port))
2337 		return 0;
2338 
2339 	if (!info->tx_buf) {
2340 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2341 		if (!info->tx_buf) {
2342 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2343 			return -ENOMEM;
2344 		}
2345 	}
2346 
2347 	info->pending_bh = 0;
2348 
2349 	memset(&info->icount, 0, sizeof(info->icount));
2350 
2351 	/* program hardware for current parameters */
2352 	change_params(info);
2353 
2354 	if (info->port.tty)
2355 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2356 
2357 	tty_port_set_initialized(&info->port, true);
2358 
2359 	return 0;
2360 }
2361 
2362 /*
2363  *  called by close() and hangup() to shutdown hardware
2364  */
2365 static void shutdown(struct slgt_info *info)
2366 {
2367 	unsigned long flags;
2368 
2369 	if (!tty_port_initialized(&info->port))
2370 		return;
2371 
2372 	DBGINFO(("%s shutdown\n", info->device_name));
2373 
2374 	/* clear status wait queue because status changes */
2375 	/* can't happen after shutting down the hardware */
2376 	wake_up_interruptible(&info->status_event_wait_q);
2377 	wake_up_interruptible(&info->event_wait_q);
2378 
2379 	del_timer_sync(&info->tx_timer);
2380 	del_timer_sync(&info->rx_timer);
2381 
2382 	kfree(info->tx_buf);
2383 	info->tx_buf = NULL;
2384 
2385 	spin_lock_irqsave(&info->lock,flags);
2386 
2387 	tx_stop(info);
2388 	rx_stop(info);
2389 
2390 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2391 
2392  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2393 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2394 		set_gtsignals(info);
2395 	}
2396 
2397 	flush_cond_wait(&info->gpio_wait_q);
2398 
2399 	spin_unlock_irqrestore(&info->lock,flags);
2400 
2401 	if (info->port.tty)
2402 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2403 
2404 	tty_port_set_initialized(&info->port, false);
2405 }
2406 
2407 static void program_hw(struct slgt_info *info)
2408 {
2409 	unsigned long flags;
2410 
2411 	spin_lock_irqsave(&info->lock,flags);
2412 
2413 	rx_stop(info);
2414 	tx_stop(info);
2415 
2416 	if (info->params.mode != MGSL_MODE_ASYNC ||
2417 	    info->netcount)
2418 		sync_mode(info);
2419 	else
2420 		async_mode(info);
2421 
2422 	set_gtsignals(info);
2423 
2424 	info->dcd_chkcount = 0;
2425 	info->cts_chkcount = 0;
2426 	info->ri_chkcount = 0;
2427 	info->dsr_chkcount = 0;
2428 
2429 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2430 	get_gtsignals(info);
2431 
2432 	if (info->netcount ||
2433 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2434 		rx_start(info);
2435 
2436 	spin_unlock_irqrestore(&info->lock,flags);
2437 }
2438 
2439 /*
2440  * reconfigure adapter based on new parameters
2441  */
2442 static void change_params(struct slgt_info *info)
2443 {
2444 	unsigned cflag;
2445 	int bits_per_char;
2446 
2447 	if (!info->port.tty)
2448 		return;
2449 	DBGINFO(("%s change_params\n", info->device_name));
2450 
2451 	cflag = info->port.tty->termios.c_cflag;
2452 
2453 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2454 	/* otherwise assert RTS and DTR */
2455  	if (cflag & CBAUD)
2456 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2457 	else
2458 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2459 
2460 	/* byte size and parity */
2461 
2462 	info->params.data_bits = tty_get_char_size(cflag);
2463 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2464 
2465 	if (cflag & PARENB)
2466 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2467 	else
2468 		info->params.parity = ASYNC_PARITY_NONE;
2469 
2470 	/* calculate number of jiffies to transmit a full
2471 	 * FIFO (32 bytes) at specified data rate
2472 	 */
2473 	bits_per_char = info->params.data_bits +
2474 			info->params.stop_bits + 1;
2475 
2476 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2477 
2478 	if (info->params.data_rate) {
2479 		info->timeout = (32*HZ*bits_per_char) /
2480 				info->params.data_rate;
2481 	}
2482 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2483 
2484 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2485 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2486 
2487 	/* process tty input control flags */
2488 
2489 	info->read_status_mask = IRQ_RXOVER;
2490 	if (I_INPCK(info->port.tty))
2491 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2492 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2493 		info->read_status_mask |= MASK_BREAK;
2494 	if (I_IGNPAR(info->port.tty))
2495 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2496 	if (I_IGNBRK(info->port.tty)) {
2497 		info->ignore_status_mask |= MASK_BREAK;
2498 		/* If ignoring parity and break indicators, ignore
2499 		 * overruns too.  (For real raw support).
2500 		 */
2501 		if (I_IGNPAR(info->port.tty))
2502 			info->ignore_status_mask |= MASK_OVERRUN;
2503 	}
2504 
2505 	program_hw(info);
2506 }
2507 
2508 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2509 {
2510 	DBGINFO(("%s get_stats\n",  info->device_name));
2511 	if (!user_icount) {
2512 		memset(&info->icount, 0, sizeof(info->icount));
2513 	} else {
2514 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2515 			return -EFAULT;
2516 	}
2517 	return 0;
2518 }
2519 
2520 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2521 {
2522 	DBGINFO(("%s get_params\n", info->device_name));
2523 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2524 		return -EFAULT;
2525 	return 0;
2526 }
2527 
2528 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2529 {
2530  	unsigned long flags;
2531 	MGSL_PARAMS tmp_params;
2532 
2533 	DBGINFO(("%s set_params\n", info->device_name));
2534 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2535 		return -EFAULT;
2536 
2537 	spin_lock_irqsave(&info->lock, flags);
2538 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2539 		info->base_clock = tmp_params.clock_speed;
2540 	else
2541 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2542 	spin_unlock_irqrestore(&info->lock, flags);
2543 
2544 	program_hw(info);
2545 
2546 	return 0;
2547 }
2548 
2549 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2550 {
2551 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2552 	if (put_user(info->idle_mode, idle_mode))
2553 		return -EFAULT;
2554 	return 0;
2555 }
2556 
2557 static int set_txidle(struct slgt_info *info, int idle_mode)
2558 {
2559  	unsigned long flags;
2560 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2561 	spin_lock_irqsave(&info->lock,flags);
2562 	info->idle_mode = idle_mode;
2563 	if (info->params.mode != MGSL_MODE_ASYNC)
2564 		tx_set_idle(info);
2565 	spin_unlock_irqrestore(&info->lock,flags);
2566 	return 0;
2567 }
2568 
2569 static int tx_enable(struct slgt_info *info, int enable)
2570 {
2571  	unsigned long flags;
2572 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2573 	spin_lock_irqsave(&info->lock,flags);
2574 	if (enable) {
2575 		if (!info->tx_enabled)
2576 			tx_start(info);
2577 	} else {
2578 		if (info->tx_enabled)
2579 			tx_stop(info);
2580 	}
2581 	spin_unlock_irqrestore(&info->lock,flags);
2582 	return 0;
2583 }
2584 
2585 /*
2586  * abort transmit HDLC frame
2587  */
2588 static int tx_abort(struct slgt_info *info)
2589 {
2590  	unsigned long flags;
2591 	DBGINFO(("%s tx_abort\n", info->device_name));
2592 	spin_lock_irqsave(&info->lock,flags);
2593 	tdma_reset(info);
2594 	spin_unlock_irqrestore(&info->lock,flags);
2595 	return 0;
2596 }
2597 
2598 static int rx_enable(struct slgt_info *info, int enable)
2599 {
2600  	unsigned long flags;
2601 	unsigned int rbuf_fill_level;
2602 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2603 	spin_lock_irqsave(&info->lock,flags);
2604 	/*
2605 	 * enable[31..16] = receive DMA buffer fill level
2606 	 * 0 = noop (leave fill level unchanged)
2607 	 * fill level must be multiple of 4 and <= buffer size
2608 	 */
2609 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2610 	if (rbuf_fill_level) {
2611 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2612 			spin_unlock_irqrestore(&info->lock, flags);
2613 			return -EINVAL;
2614 		}
2615 		info->rbuf_fill_level = rbuf_fill_level;
2616 		if (rbuf_fill_level < 128)
2617 			info->rx_pio = 1; /* PIO mode */
2618 		else
2619 			info->rx_pio = 0; /* DMA mode */
2620 		rx_stop(info); /* restart receiver to use new fill level */
2621 	}
2622 
2623 	/*
2624 	 * enable[1..0] = receiver enable command
2625 	 * 0 = disable
2626 	 * 1 = enable
2627 	 * 2 = enable or force hunt mode if already enabled
2628 	 */
2629 	enable &= 3;
2630 	if (enable) {
2631 		if (!info->rx_enabled)
2632 			rx_start(info);
2633 		else if (enable == 2) {
2634 			/* force hunt mode (write 1 to RCR[3]) */
2635 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2636 		}
2637 	} else {
2638 		if (info->rx_enabled)
2639 			rx_stop(info);
2640 	}
2641 	spin_unlock_irqrestore(&info->lock,flags);
2642 	return 0;
2643 }
2644 
2645 /*
2646  *  wait for specified event to occur
2647  */
2648 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2649 {
2650  	unsigned long flags;
2651 	int s;
2652 	int rc=0;
2653 	struct mgsl_icount cprev, cnow;
2654 	int events;
2655 	int mask;
2656 	struct	_input_signal_events oldsigs, newsigs;
2657 	DECLARE_WAITQUEUE(wait, current);
2658 
2659 	if (get_user(mask, mask_ptr))
2660 		return -EFAULT;
2661 
2662 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2663 
2664 	spin_lock_irqsave(&info->lock,flags);
2665 
2666 	/* return immediately if state matches requested events */
2667 	get_gtsignals(info);
2668 	s = info->signals;
2669 
2670 	events = mask &
2671 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2672  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2673 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2674 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2675 	if (events) {
2676 		spin_unlock_irqrestore(&info->lock,flags);
2677 		goto exit;
2678 	}
2679 
2680 	/* save current irq counts */
2681 	cprev = info->icount;
2682 	oldsigs = info->input_signal_events;
2683 
2684 	/* enable hunt and idle irqs if needed */
2685 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2686 		unsigned short val = rd_reg16(info, SCR);
2687 		if (!(val & IRQ_RXIDLE))
2688 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2689 	}
2690 
2691 	set_current_state(TASK_INTERRUPTIBLE);
2692 	add_wait_queue(&info->event_wait_q, &wait);
2693 
2694 	spin_unlock_irqrestore(&info->lock,flags);
2695 
2696 	for(;;) {
2697 		schedule();
2698 		if (signal_pending(current)) {
2699 			rc = -ERESTARTSYS;
2700 			break;
2701 		}
2702 
2703 		/* get current irq counts */
2704 		spin_lock_irqsave(&info->lock,flags);
2705 		cnow = info->icount;
2706 		newsigs = info->input_signal_events;
2707 		set_current_state(TASK_INTERRUPTIBLE);
2708 		spin_unlock_irqrestore(&info->lock,flags);
2709 
2710 		/* if no change, wait aborted for some reason */
2711 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2712 		    newsigs.dsr_down == oldsigs.dsr_down &&
2713 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2714 		    newsigs.dcd_down == oldsigs.dcd_down &&
2715 		    newsigs.cts_up   == oldsigs.cts_up   &&
2716 		    newsigs.cts_down == oldsigs.cts_down &&
2717 		    newsigs.ri_up    == oldsigs.ri_up    &&
2718 		    newsigs.ri_down  == oldsigs.ri_down  &&
2719 		    cnow.exithunt    == cprev.exithunt   &&
2720 		    cnow.rxidle      == cprev.rxidle) {
2721 			rc = -EIO;
2722 			break;
2723 		}
2724 
2725 		events = mask &
2726 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2727 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2728 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2729 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2730 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2731 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2732 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2733 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2734 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2735 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2736 		if (events)
2737 			break;
2738 
2739 		cprev = cnow;
2740 		oldsigs = newsigs;
2741 	}
2742 
2743 	remove_wait_queue(&info->event_wait_q, &wait);
2744 	set_current_state(TASK_RUNNING);
2745 
2746 
2747 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2748 		spin_lock_irqsave(&info->lock,flags);
2749 		if (!waitqueue_active(&info->event_wait_q)) {
2750 			/* disable enable exit hunt mode/idle rcvd IRQs */
2751 			wr_reg16(info, SCR,
2752 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2753 		}
2754 		spin_unlock_irqrestore(&info->lock,flags);
2755 	}
2756 exit:
2757 	if (rc == 0)
2758 		rc = put_user(events, mask_ptr);
2759 	return rc;
2760 }
2761 
2762 static int get_interface(struct slgt_info *info, int __user *if_mode)
2763 {
2764 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2765 	if (put_user(info->if_mode, if_mode))
2766 		return -EFAULT;
2767 	return 0;
2768 }
2769 
2770 static int set_interface(struct slgt_info *info, int if_mode)
2771 {
2772  	unsigned long flags;
2773 	unsigned short val;
2774 
2775 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2776 	spin_lock_irqsave(&info->lock,flags);
2777 	info->if_mode = if_mode;
2778 
2779 	msc_set_vcr(info);
2780 
2781 	/* TCR (tx control) 07  1=RTS driver control */
2782 	val = rd_reg16(info, TCR);
2783 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2784 		val |= BIT7;
2785 	else
2786 		val &= ~BIT7;
2787 	wr_reg16(info, TCR, val);
2788 
2789 	spin_unlock_irqrestore(&info->lock,flags);
2790 	return 0;
2791 }
2792 
2793 static int get_xsync(struct slgt_info *info, int __user *xsync)
2794 {
2795 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2796 	if (put_user(info->xsync, xsync))
2797 		return -EFAULT;
2798 	return 0;
2799 }
2800 
2801 /*
2802  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2803  *
2804  * sync pattern is contained in least significant bytes of value
2805  * most significant byte of sync pattern is oldest (1st sent/detected)
2806  */
2807 static int set_xsync(struct slgt_info *info, int xsync)
2808 {
2809 	unsigned long flags;
2810 
2811 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2812 	spin_lock_irqsave(&info->lock, flags);
2813 	info->xsync = xsync;
2814 	wr_reg32(info, XSR, xsync);
2815 	spin_unlock_irqrestore(&info->lock, flags);
2816 	return 0;
2817 }
2818 
2819 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2820 {
2821 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2822 	if (put_user(info->xctrl, xctrl))
2823 		return -EFAULT;
2824 	return 0;
2825 }
2826 
2827 /*
2828  * set extended control options
2829  *
2830  * xctrl[31:19] reserved, must be zero
2831  * xctrl[18:17] extended sync pattern length in bytes
2832  *              00 = 1 byte  in xsr[7:0]
2833  *              01 = 2 bytes in xsr[15:0]
2834  *              10 = 3 bytes in xsr[23:0]
2835  *              11 = 4 bytes in xsr[31:0]
2836  * xctrl[16]    1 = enable terminal count, 0=disabled
2837  * xctrl[15:0]  receive terminal count for fixed length packets
2838  *              value is count minus one (0 = 1 byte packet)
2839  *              when terminal count is reached, receiver
2840  *              automatically returns to hunt mode and receive
2841  *              FIFO contents are flushed to DMA buffers with
2842  *              end of frame (EOF) status
2843  */
2844 static int set_xctrl(struct slgt_info *info, int xctrl)
2845 {
2846 	unsigned long flags;
2847 
2848 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2849 	spin_lock_irqsave(&info->lock, flags);
2850 	info->xctrl = xctrl;
2851 	wr_reg32(info, XCR, xctrl);
2852 	spin_unlock_irqrestore(&info->lock, flags);
2853 	return 0;
2854 }
2855 
2856 /*
2857  * set general purpose IO pin state and direction
2858  *
2859  * user_gpio fields:
2860  * state   each bit indicates a pin state
2861  * smask   set bit indicates pin state to set
2862  * dir     each bit indicates a pin direction (0=input, 1=output)
2863  * dmask   set bit indicates pin direction to set
2864  */
2865 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2866 {
2867  	unsigned long flags;
2868 	struct gpio_desc gpio;
2869 	__u32 data;
2870 
2871 	if (!info->gpio_present)
2872 		return -EINVAL;
2873 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2874 		return -EFAULT;
2875 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2876 		 info->device_name, gpio.state, gpio.smask,
2877 		 gpio.dir, gpio.dmask));
2878 
2879 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2880 	if (gpio.dmask) {
2881 		data = rd_reg32(info, IODR);
2882 		data |= gpio.dmask & gpio.dir;
2883 		data &= ~(gpio.dmask & ~gpio.dir);
2884 		wr_reg32(info, IODR, data);
2885 	}
2886 	if (gpio.smask) {
2887 		data = rd_reg32(info, IOVR);
2888 		data |= gpio.smask & gpio.state;
2889 		data &= ~(gpio.smask & ~gpio.state);
2890 		wr_reg32(info, IOVR, data);
2891 	}
2892 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2893 
2894 	return 0;
2895 }
2896 
2897 /*
2898  * get general purpose IO pin state and direction
2899  */
2900 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2901 {
2902 	struct gpio_desc gpio;
2903 	if (!info->gpio_present)
2904 		return -EINVAL;
2905 	gpio.state = rd_reg32(info, IOVR);
2906 	gpio.smask = 0xffffffff;
2907 	gpio.dir   = rd_reg32(info, IODR);
2908 	gpio.dmask = 0xffffffff;
2909 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2910 		return -EFAULT;
2911 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2912 		 info->device_name, gpio.state, gpio.dir));
2913 	return 0;
2914 }
2915 
2916 /*
2917  * conditional wait facility
2918  */
2919 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2920 {
2921 	init_waitqueue_head(&w->q);
2922 	init_waitqueue_entry(&w->wait, current);
2923 	w->data = data;
2924 }
2925 
2926 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2927 {
2928 	set_current_state(TASK_INTERRUPTIBLE);
2929 	add_wait_queue(&w->q, &w->wait);
2930 	w->next = *head;
2931 	*head = w;
2932 }
2933 
2934 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2935 {
2936 	struct cond_wait *w, *prev;
2937 	remove_wait_queue(&cw->q, &cw->wait);
2938 	set_current_state(TASK_RUNNING);
2939 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2940 		if (w == cw) {
2941 			if (prev != NULL)
2942 				prev->next = w->next;
2943 			else
2944 				*head = w->next;
2945 			break;
2946 		}
2947 	}
2948 }
2949 
2950 static void flush_cond_wait(struct cond_wait **head)
2951 {
2952 	while (*head != NULL) {
2953 		wake_up_interruptible(&(*head)->q);
2954 		*head = (*head)->next;
2955 	}
2956 }
2957 
2958 /*
2959  * wait for general purpose I/O pin(s) to enter specified state
2960  *
2961  * user_gpio fields:
2962  * state - bit indicates target pin state
2963  * smask - set bit indicates watched pin
2964  *
2965  * The wait ends when at least one watched pin enters the specified
2966  * state. When 0 (no error) is returned, user_gpio->state is set to the
2967  * state of all GPIO pins when the wait ends.
2968  *
2969  * Note: Each pin may be a dedicated input, dedicated output, or
2970  * configurable input/output. The number and configuration of pins
2971  * varies with the specific adapter model. Only input pins (dedicated
2972  * or configured) can be monitored with this function.
2973  */
2974 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2975 {
2976  	unsigned long flags;
2977 	int rc = 0;
2978 	struct gpio_desc gpio;
2979 	struct cond_wait wait;
2980 	u32 state;
2981 
2982 	if (!info->gpio_present)
2983 		return -EINVAL;
2984 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2985 		return -EFAULT;
2986 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
2987 		 info->device_name, gpio.state, gpio.smask));
2988 	/* ignore output pins identified by set IODR bit */
2989 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
2990 		return -EINVAL;
2991 	init_cond_wait(&wait, gpio.smask);
2992 
2993 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2994 	/* enable interrupts for watched pins */
2995 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
2996 	/* get current pin states */
2997 	state = rd_reg32(info, IOVR);
2998 
2999 	if (gpio.smask & ~(state ^ gpio.state)) {
3000 		/* already in target state */
3001 		gpio.state = state;
3002 	} else {
3003 		/* wait for target state */
3004 		add_cond_wait(&info->gpio_wait_q, &wait);
3005 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3006 		schedule();
3007 		if (signal_pending(current))
3008 			rc = -ERESTARTSYS;
3009 		else
3010 			gpio.state = wait.data;
3011 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3012 		remove_cond_wait(&info->gpio_wait_q, &wait);
3013 	}
3014 
3015 	/* disable all GPIO interrupts if no waiting processes */
3016 	if (info->gpio_wait_q == NULL)
3017 		wr_reg32(info, IOER, 0);
3018 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3019 
3020 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3021 		rc = -EFAULT;
3022 	return rc;
3023 }
3024 
3025 static int modem_input_wait(struct slgt_info *info,int arg)
3026 {
3027  	unsigned long flags;
3028 	int rc;
3029 	struct mgsl_icount cprev, cnow;
3030 	DECLARE_WAITQUEUE(wait, current);
3031 
3032 	/* save current irq counts */
3033 	spin_lock_irqsave(&info->lock,flags);
3034 	cprev = info->icount;
3035 	add_wait_queue(&info->status_event_wait_q, &wait);
3036 	set_current_state(TASK_INTERRUPTIBLE);
3037 	spin_unlock_irqrestore(&info->lock,flags);
3038 
3039 	for(;;) {
3040 		schedule();
3041 		if (signal_pending(current)) {
3042 			rc = -ERESTARTSYS;
3043 			break;
3044 		}
3045 
3046 		/* get new irq counts */
3047 		spin_lock_irqsave(&info->lock,flags);
3048 		cnow = info->icount;
3049 		set_current_state(TASK_INTERRUPTIBLE);
3050 		spin_unlock_irqrestore(&info->lock,flags);
3051 
3052 		/* if no change, wait aborted for some reason */
3053 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3054 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3055 			rc = -EIO;
3056 			break;
3057 		}
3058 
3059 		/* check for change in caller specified modem input */
3060 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3061 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3062 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3063 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3064 			rc = 0;
3065 			break;
3066 		}
3067 
3068 		cprev = cnow;
3069 	}
3070 	remove_wait_queue(&info->status_event_wait_q, &wait);
3071 	set_current_state(TASK_RUNNING);
3072 	return rc;
3073 }
3074 
3075 /*
3076  *  return state of serial control and status signals
3077  */
3078 static int tiocmget(struct tty_struct *tty)
3079 {
3080 	struct slgt_info *info = tty->driver_data;
3081 	unsigned int result;
3082  	unsigned long flags;
3083 
3084 	spin_lock_irqsave(&info->lock,flags);
3085  	get_gtsignals(info);
3086 	spin_unlock_irqrestore(&info->lock,flags);
3087 
3088 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3089 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3090 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3091 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3092 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3093 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3094 
3095 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3096 	return result;
3097 }
3098 
3099 /*
3100  * set modem control signals (DTR/RTS)
3101  *
3102  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3103  *		TIOCMSET = set/clear signal values
3104  * 	value	bit mask for command
3105  */
3106 static int tiocmset(struct tty_struct *tty,
3107 		    unsigned int set, unsigned int clear)
3108 {
3109 	struct slgt_info *info = tty->driver_data;
3110  	unsigned long flags;
3111 
3112 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3113 
3114 	if (set & TIOCM_RTS)
3115 		info->signals |= SerialSignal_RTS;
3116 	if (set & TIOCM_DTR)
3117 		info->signals |= SerialSignal_DTR;
3118 	if (clear & TIOCM_RTS)
3119 		info->signals &= ~SerialSignal_RTS;
3120 	if (clear & TIOCM_DTR)
3121 		info->signals &= ~SerialSignal_DTR;
3122 
3123 	spin_lock_irqsave(&info->lock,flags);
3124 	set_gtsignals(info);
3125 	spin_unlock_irqrestore(&info->lock,flags);
3126 	return 0;
3127 }
3128 
3129 static int carrier_raised(struct tty_port *port)
3130 {
3131 	unsigned long flags;
3132 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3133 
3134 	spin_lock_irqsave(&info->lock,flags);
3135 	get_gtsignals(info);
3136 	spin_unlock_irqrestore(&info->lock,flags);
3137 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3138 }
3139 
3140 static void dtr_rts(struct tty_port *port, int on)
3141 {
3142 	unsigned long flags;
3143 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3144 
3145 	spin_lock_irqsave(&info->lock,flags);
3146 	if (on)
3147 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3148 	else
3149 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3150 	set_gtsignals(info);
3151 	spin_unlock_irqrestore(&info->lock,flags);
3152 }
3153 
3154 
3155 /*
3156  *  block current process until the device is ready to open
3157  */
3158 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3159 			   struct slgt_info *info)
3160 {
3161 	DECLARE_WAITQUEUE(wait, current);
3162 	int		retval;
3163 	bool		do_clocal = false;
3164 	unsigned long	flags;
3165 	int		cd;
3166 	struct tty_port *port = &info->port;
3167 
3168 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3169 
3170 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3171 		/* nonblock mode is set or port is not enabled */
3172 		tty_port_set_active(port, true);
3173 		return 0;
3174 	}
3175 
3176 	if (C_CLOCAL(tty))
3177 		do_clocal = true;
3178 
3179 	/* Wait for carrier detect and the line to become
3180 	 * free (i.e., not in use by the callout).  While we are in
3181 	 * this loop, port->count is dropped by one, so that
3182 	 * close() knows when to free things.  We restore it upon
3183 	 * exit, either normal or abnormal.
3184 	 */
3185 
3186 	retval = 0;
3187 	add_wait_queue(&port->open_wait, &wait);
3188 
3189 	spin_lock_irqsave(&info->lock, flags);
3190 	port->count--;
3191 	spin_unlock_irqrestore(&info->lock, flags);
3192 	port->blocked_open++;
3193 
3194 	while (1) {
3195 		if (C_BAUD(tty) && tty_port_initialized(port))
3196 			tty_port_raise_dtr_rts(port);
3197 
3198 		set_current_state(TASK_INTERRUPTIBLE);
3199 
3200 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3201 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3202 					-EAGAIN : -ERESTARTSYS;
3203 			break;
3204 		}
3205 
3206 		cd = tty_port_carrier_raised(port);
3207 		if (do_clocal || cd)
3208 			break;
3209 
3210 		if (signal_pending(current)) {
3211 			retval = -ERESTARTSYS;
3212 			break;
3213 		}
3214 
3215 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3216 		tty_unlock(tty);
3217 		schedule();
3218 		tty_lock(tty);
3219 	}
3220 
3221 	set_current_state(TASK_RUNNING);
3222 	remove_wait_queue(&port->open_wait, &wait);
3223 
3224 	if (!tty_hung_up_p(filp))
3225 		port->count++;
3226 	port->blocked_open--;
3227 
3228 	if (!retval)
3229 		tty_port_set_active(port, true);
3230 
3231 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3232 	return retval;
3233 }
3234 
3235 /*
3236  * allocate buffers used for calling line discipline receive_buf
3237  * directly in synchronous mode
3238  * note: add 5 bytes to max frame size to allow appending
3239  * 32-bit CRC and status byte when configured to do so
3240  */
3241 static int alloc_tmp_rbuf(struct slgt_info *info)
3242 {
3243 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3244 	if (info->tmp_rbuf == NULL)
3245 		return -ENOMEM;
3246 	/* unused flag buffer to satisfy receive_buf calling interface */
3247 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3248 	if (!info->flag_buf) {
3249 		kfree(info->tmp_rbuf);
3250 		info->tmp_rbuf = NULL;
3251 		return -ENOMEM;
3252 	}
3253 	return 0;
3254 }
3255 
3256 static void free_tmp_rbuf(struct slgt_info *info)
3257 {
3258 	kfree(info->tmp_rbuf);
3259 	info->tmp_rbuf = NULL;
3260 	kfree(info->flag_buf);
3261 	info->flag_buf = NULL;
3262 }
3263 
3264 /*
3265  * allocate DMA descriptor lists.
3266  */
3267 static int alloc_desc(struct slgt_info *info)
3268 {
3269 	unsigned int i;
3270 	unsigned int pbufs;
3271 
3272 	/* allocate memory to hold descriptor lists */
3273 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3274 					&info->bufs_dma_addr, GFP_KERNEL);
3275 	if (info->bufs == NULL)
3276 		return -ENOMEM;
3277 
3278 	info->rbufs = (struct slgt_desc*)info->bufs;
3279 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3280 
3281 	pbufs = (unsigned int)info->bufs_dma_addr;
3282 
3283 	/*
3284 	 * Build circular lists of descriptors
3285 	 */
3286 
3287 	for (i=0; i < info->rbuf_count; i++) {
3288 		/* physical address of this descriptor */
3289 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3290 
3291 		/* physical address of next descriptor */
3292 		if (i == info->rbuf_count - 1)
3293 			info->rbufs[i].next = cpu_to_le32(pbufs);
3294 		else
3295 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3296 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3297 	}
3298 
3299 	for (i=0; i < info->tbuf_count; i++) {
3300 		/* physical address of this descriptor */
3301 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3302 
3303 		/* physical address of next descriptor */
3304 		if (i == info->tbuf_count - 1)
3305 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3306 		else
3307 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3308 	}
3309 
3310 	return 0;
3311 }
3312 
3313 static void free_desc(struct slgt_info *info)
3314 {
3315 	if (info->bufs != NULL) {
3316 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3317 				  info->bufs, info->bufs_dma_addr);
3318 		info->bufs  = NULL;
3319 		info->rbufs = NULL;
3320 		info->tbufs = NULL;
3321 	}
3322 }
3323 
3324 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3325 {
3326 	int i;
3327 	for (i=0; i < count; i++) {
3328 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3329 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3330 		if (!bufs[i].buf)
3331 			return -ENOMEM;
3332 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3333 	}
3334 	return 0;
3335 }
3336 
3337 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3338 {
3339 	int i;
3340 	for (i=0; i < count; i++) {
3341 		if (bufs[i].buf == NULL)
3342 			continue;
3343 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3344 				  bufs[i].buf_dma_addr);
3345 		bufs[i].buf = NULL;
3346 	}
3347 }
3348 
3349 static int alloc_dma_bufs(struct slgt_info *info)
3350 {
3351 	info->rbuf_count = 32;
3352 	info->tbuf_count = 32;
3353 
3354 	if (alloc_desc(info) < 0 ||
3355 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3356 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3357 	    alloc_tmp_rbuf(info) < 0) {
3358 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3359 		return -ENOMEM;
3360 	}
3361 	reset_rbufs(info);
3362 	return 0;
3363 }
3364 
3365 static void free_dma_bufs(struct slgt_info *info)
3366 {
3367 	if (info->bufs) {
3368 		free_bufs(info, info->rbufs, info->rbuf_count);
3369 		free_bufs(info, info->tbufs, info->tbuf_count);
3370 		free_desc(info);
3371 	}
3372 	free_tmp_rbuf(info);
3373 }
3374 
3375 static int claim_resources(struct slgt_info *info)
3376 {
3377 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3378 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3379 			info->device_name, info->phys_reg_addr));
3380 		info->init_error = DiagStatus_AddressConflict;
3381 		goto errout;
3382 	}
3383 	else
3384 		info->reg_addr_requested = true;
3385 
3386 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3387 	if (!info->reg_addr) {
3388 		DBGERR(("%s can't map device registers, addr=%08X\n",
3389 			info->device_name, info->phys_reg_addr));
3390 		info->init_error = DiagStatus_CantAssignPciResources;
3391 		goto errout;
3392 	}
3393 	return 0;
3394 
3395 errout:
3396 	release_resources(info);
3397 	return -ENODEV;
3398 }
3399 
3400 static void release_resources(struct slgt_info *info)
3401 {
3402 	if (info->irq_requested) {
3403 		free_irq(info->irq_level, info);
3404 		info->irq_requested = false;
3405 	}
3406 
3407 	if (info->reg_addr_requested) {
3408 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3409 		info->reg_addr_requested = false;
3410 	}
3411 
3412 	if (info->reg_addr) {
3413 		iounmap(info->reg_addr);
3414 		info->reg_addr = NULL;
3415 	}
3416 }
3417 
3418 /* Add the specified device instance data structure to the
3419  * global linked list of devices and increment the device count.
3420  */
3421 static void add_device(struct slgt_info *info)
3422 {
3423 	char *devstr;
3424 
3425 	info->next_device = NULL;
3426 	info->line = slgt_device_count;
3427 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3428 
3429 	if (info->line < MAX_DEVICES) {
3430 		if (maxframe[info->line])
3431 			info->max_frame_size = maxframe[info->line];
3432 	}
3433 
3434 	slgt_device_count++;
3435 
3436 	if (!slgt_device_list)
3437 		slgt_device_list = info;
3438 	else {
3439 		struct slgt_info *current_dev = slgt_device_list;
3440 		while(current_dev->next_device)
3441 			current_dev = current_dev->next_device;
3442 		current_dev->next_device = info;
3443 	}
3444 
3445 	if (info->max_frame_size < 4096)
3446 		info->max_frame_size = 4096;
3447 	else if (info->max_frame_size > 65535)
3448 		info->max_frame_size = 65535;
3449 
3450 	switch(info->pdev->device) {
3451 	case SYNCLINK_GT_DEVICE_ID:
3452 		devstr = "GT";
3453 		break;
3454 	case SYNCLINK_GT2_DEVICE_ID:
3455 		devstr = "GT2";
3456 		break;
3457 	case SYNCLINK_GT4_DEVICE_ID:
3458 		devstr = "GT4";
3459 		break;
3460 	case SYNCLINK_AC_DEVICE_ID:
3461 		devstr = "AC";
3462 		info->params.mode = MGSL_MODE_ASYNC;
3463 		break;
3464 	default:
3465 		devstr = "(unknown model)";
3466 	}
3467 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3468 		devstr, info->device_name, info->phys_reg_addr,
3469 		info->irq_level, info->max_frame_size);
3470 
3471 #if SYNCLINK_GENERIC_HDLC
3472 	hdlcdev_init(info);
3473 #endif
3474 }
3475 
3476 static const struct tty_port_operations slgt_port_ops = {
3477 	.carrier_raised = carrier_raised,
3478 	.dtr_rts = dtr_rts,
3479 };
3480 
3481 /*
3482  *  allocate device instance structure, return NULL on failure
3483  */
3484 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3485 {
3486 	struct slgt_info *info;
3487 
3488 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3489 
3490 	if (!info) {
3491 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3492 			driver_name, adapter_num, port_num));
3493 	} else {
3494 		tty_port_init(&info->port);
3495 		info->port.ops = &slgt_port_ops;
3496 		INIT_WORK(&info->task, bh_handler);
3497 		info->max_frame_size = 4096;
3498 		info->base_clock = 14745600;
3499 		info->rbuf_fill_level = DMABUFSIZE;
3500 		init_waitqueue_head(&info->status_event_wait_q);
3501 		init_waitqueue_head(&info->event_wait_q);
3502 		spin_lock_init(&info->netlock);
3503 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3504 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3505 		info->adapter_num = adapter_num;
3506 		info->port_num = port_num;
3507 
3508 		timer_setup(&info->tx_timer, tx_timeout, 0);
3509 		timer_setup(&info->rx_timer, rx_timeout, 0);
3510 
3511 		/* Copy configuration info to device instance data */
3512 		info->pdev = pdev;
3513 		info->irq_level = pdev->irq;
3514 		info->phys_reg_addr = pci_resource_start(pdev,0);
3515 
3516 		info->bus_type = MGSL_BUS_TYPE_PCI;
3517 		info->irq_flags = IRQF_SHARED;
3518 
3519 		info->init_error = -1; /* assume error, set to 0 on successful init */
3520 	}
3521 
3522 	return info;
3523 }
3524 
3525 static void device_init(int adapter_num, struct pci_dev *pdev)
3526 {
3527 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3528 	int i;
3529 	int port_count = 1;
3530 
3531 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3532 		port_count = 2;
3533 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3534 		port_count = 4;
3535 
3536 	/* allocate device instances for all ports */
3537 	for (i=0; i < port_count; ++i) {
3538 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3539 		if (port_array[i] == NULL) {
3540 			for (--i; i >= 0; --i) {
3541 				tty_port_destroy(&port_array[i]->port);
3542 				kfree(port_array[i]);
3543 			}
3544 			return;
3545 		}
3546 	}
3547 
3548 	/* give copy of port_array to all ports and add to device list  */
3549 	for (i=0; i < port_count; ++i) {
3550 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3551 		add_device(port_array[i]);
3552 		port_array[i]->port_count = port_count;
3553 		spin_lock_init(&port_array[i]->lock);
3554 	}
3555 
3556 	/* Allocate and claim adapter resources */
3557 	if (!claim_resources(port_array[0])) {
3558 
3559 		alloc_dma_bufs(port_array[0]);
3560 
3561 		/* copy resource information from first port to others */
3562 		for (i = 1; i < port_count; ++i) {
3563 			port_array[i]->irq_level = port_array[0]->irq_level;
3564 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3565 			alloc_dma_bufs(port_array[i]);
3566 		}
3567 
3568 		if (request_irq(port_array[0]->irq_level,
3569 					slgt_interrupt,
3570 					port_array[0]->irq_flags,
3571 					port_array[0]->device_name,
3572 					port_array[0]) < 0) {
3573 			DBGERR(("%s request_irq failed IRQ=%d\n",
3574 				port_array[0]->device_name,
3575 				port_array[0]->irq_level));
3576 		} else {
3577 			port_array[0]->irq_requested = true;
3578 			adapter_test(port_array[0]);
3579 			for (i=1 ; i < port_count ; i++) {
3580 				port_array[i]->init_error = port_array[0]->init_error;
3581 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3582 			}
3583 		}
3584 	}
3585 
3586 	for (i = 0; i < port_count; ++i) {
3587 		struct slgt_info *info = port_array[i];
3588 		tty_port_register_device(&info->port, serial_driver, info->line,
3589 				&info->pdev->dev);
3590 	}
3591 }
3592 
3593 static int init_one(struct pci_dev *dev,
3594 			      const struct pci_device_id *ent)
3595 {
3596 	if (pci_enable_device(dev)) {
3597 		printk("error enabling pci device %p\n", dev);
3598 		return -EIO;
3599 	}
3600 	pci_set_master(dev);
3601 	device_init(slgt_device_count, dev);
3602 	return 0;
3603 }
3604 
3605 static void remove_one(struct pci_dev *dev)
3606 {
3607 }
3608 
3609 static const struct tty_operations ops = {
3610 	.open = open,
3611 	.close = close,
3612 	.write = write,
3613 	.put_char = put_char,
3614 	.flush_chars = flush_chars,
3615 	.write_room = write_room,
3616 	.chars_in_buffer = chars_in_buffer,
3617 	.flush_buffer = flush_buffer,
3618 	.ioctl = ioctl,
3619 	.compat_ioctl = slgt_compat_ioctl,
3620 	.throttle = throttle,
3621 	.unthrottle = unthrottle,
3622 	.send_xchar = send_xchar,
3623 	.break_ctl = set_break,
3624 	.wait_until_sent = wait_until_sent,
3625 	.set_termios = set_termios,
3626 	.stop = tx_hold,
3627 	.start = tx_release,
3628 	.hangup = hangup,
3629 	.tiocmget = tiocmget,
3630 	.tiocmset = tiocmset,
3631 	.get_icount = get_icount,
3632 	.proc_show = synclink_gt_proc_show,
3633 };
3634 
3635 static void slgt_cleanup(void)
3636 {
3637 	struct slgt_info *info;
3638 	struct slgt_info *tmp;
3639 
3640 	printk(KERN_INFO "unload %s\n", driver_name);
3641 
3642 	if (serial_driver) {
3643 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3644 			tty_unregister_device(serial_driver, info->line);
3645 		tty_unregister_driver(serial_driver);
3646 		tty_driver_kref_put(serial_driver);
3647 	}
3648 
3649 	/* reset devices */
3650 	info = slgt_device_list;
3651 	while(info) {
3652 		reset_port(info);
3653 		info = info->next_device;
3654 	}
3655 
3656 	/* release devices */
3657 	info = slgt_device_list;
3658 	while(info) {
3659 #if SYNCLINK_GENERIC_HDLC
3660 		hdlcdev_exit(info);
3661 #endif
3662 		free_dma_bufs(info);
3663 		free_tmp_rbuf(info);
3664 		if (info->port_num == 0)
3665 			release_resources(info);
3666 		tmp = info;
3667 		info = info->next_device;
3668 		tty_port_destroy(&tmp->port);
3669 		kfree(tmp);
3670 	}
3671 
3672 	if (pci_registered)
3673 		pci_unregister_driver(&pci_driver);
3674 }
3675 
3676 /*
3677  *  Driver initialization entry point.
3678  */
3679 static int __init slgt_init(void)
3680 {
3681 	int rc;
3682 
3683 	printk(KERN_INFO "%s\n", driver_name);
3684 
3685 	serial_driver = tty_alloc_driver(MAX_DEVICES, TTY_DRIVER_REAL_RAW |
3686 			TTY_DRIVER_DYNAMIC_DEV);
3687 	if (IS_ERR(serial_driver)) {
3688 		printk("%s can't allocate tty driver\n", driver_name);
3689 		return PTR_ERR(serial_driver);
3690 	}
3691 
3692 	/* Initialize the tty_driver structure */
3693 
3694 	serial_driver->driver_name = slgt_driver_name;
3695 	serial_driver->name = tty_dev_prefix;
3696 	serial_driver->major = ttymajor;
3697 	serial_driver->minor_start = 64;
3698 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3699 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3700 	serial_driver->init_termios = tty_std_termios;
3701 	serial_driver->init_termios.c_cflag =
3702 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3703 	serial_driver->init_termios.c_ispeed = 9600;
3704 	serial_driver->init_termios.c_ospeed = 9600;
3705 	tty_set_operations(serial_driver, &ops);
3706 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3707 		DBGERR(("%s can't register serial driver\n", driver_name));
3708 		tty_driver_kref_put(serial_driver);
3709 		serial_driver = NULL;
3710 		goto error;
3711 	}
3712 
3713 	printk(KERN_INFO "%s, tty major#%d\n",
3714 	       driver_name, serial_driver->major);
3715 
3716 	slgt_device_count = 0;
3717 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3718 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3719 		goto error;
3720 	}
3721 	pci_registered = true;
3722 
3723 	if (!slgt_device_list)
3724 		printk("%s no devices found\n",driver_name);
3725 
3726 	return 0;
3727 
3728 error:
3729 	slgt_cleanup();
3730 	return rc;
3731 }
3732 
3733 static void __exit slgt_exit(void)
3734 {
3735 	slgt_cleanup();
3736 }
3737 
3738 module_init(slgt_init);
3739 module_exit(slgt_exit);
3740 
3741 /*
3742  * register access routines
3743  */
3744 
3745 #define CALC_REGADDR() \
3746 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3747 	if (addr >= 0x80) \
3748 		reg_addr += (info->port_num) * 32; \
3749 	else if (addr >= 0x40)	\
3750 		reg_addr += (info->port_num) * 16;
3751 
3752 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3753 {
3754 	CALC_REGADDR();
3755 	return readb((void __iomem *)reg_addr);
3756 }
3757 
3758 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3759 {
3760 	CALC_REGADDR();
3761 	writeb(value, (void __iomem *)reg_addr);
3762 }
3763 
3764 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3765 {
3766 	CALC_REGADDR();
3767 	return readw((void __iomem *)reg_addr);
3768 }
3769 
3770 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3771 {
3772 	CALC_REGADDR();
3773 	writew(value, (void __iomem *)reg_addr);
3774 }
3775 
3776 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3777 {
3778 	CALC_REGADDR();
3779 	return readl((void __iomem *)reg_addr);
3780 }
3781 
3782 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3783 {
3784 	CALC_REGADDR();
3785 	writel(value, (void __iomem *)reg_addr);
3786 }
3787 
3788 static void rdma_reset(struct slgt_info *info)
3789 {
3790 	unsigned int i;
3791 
3792 	/* set reset bit */
3793 	wr_reg32(info, RDCSR, BIT1);
3794 
3795 	/* wait for enable bit cleared */
3796 	for(i=0 ; i < 1000 ; i++)
3797 		if (!(rd_reg32(info, RDCSR) & BIT0))
3798 			break;
3799 }
3800 
3801 static void tdma_reset(struct slgt_info *info)
3802 {
3803 	unsigned int i;
3804 
3805 	/* set reset bit */
3806 	wr_reg32(info, TDCSR, BIT1);
3807 
3808 	/* wait for enable bit cleared */
3809 	for(i=0 ; i < 1000 ; i++)
3810 		if (!(rd_reg32(info, TDCSR) & BIT0))
3811 			break;
3812 }
3813 
3814 /*
3815  * enable internal loopback
3816  * TxCLK and RxCLK are generated from BRG
3817  * and TxD is looped back to RxD internally.
3818  */
3819 static void enable_loopback(struct slgt_info *info)
3820 {
3821 	/* SCR (serial control) BIT2=loopback enable */
3822 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3823 
3824 	if (info->params.mode != MGSL_MODE_ASYNC) {
3825 		/* CCR (clock control)
3826 		 * 07..05  tx clock source (010 = BRG)
3827 		 * 04..02  rx clock source (010 = BRG)
3828 		 * 01      auxclk enable   (0 = disable)
3829 		 * 00      BRG enable      (1 = enable)
3830 		 *
3831 		 * 0100 1001
3832 		 */
3833 		wr_reg8(info, CCR, 0x49);
3834 
3835 		/* set speed if available, otherwise use default */
3836 		if (info->params.clock_speed)
3837 			set_rate(info, info->params.clock_speed);
3838 		else
3839 			set_rate(info, 3686400);
3840 	}
3841 }
3842 
3843 /*
3844  *  set baud rate generator to specified rate
3845  */
3846 static void set_rate(struct slgt_info *info, u32 rate)
3847 {
3848 	unsigned int div;
3849 	unsigned int osc = info->base_clock;
3850 
3851 	/* div = osc/rate - 1
3852 	 *
3853 	 * Round div up if osc/rate is not integer to
3854 	 * force to next slowest rate.
3855 	 */
3856 
3857 	if (rate) {
3858 		div = osc/rate;
3859 		if (!(osc % rate) && div)
3860 			div--;
3861 		wr_reg16(info, BDR, (unsigned short)div);
3862 	}
3863 }
3864 
3865 static void rx_stop(struct slgt_info *info)
3866 {
3867 	unsigned short val;
3868 
3869 	/* disable and reset receiver */
3870 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3871 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3872 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3873 
3874 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3875 
3876 	/* clear pending rx interrupts */
3877 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3878 
3879 	rdma_reset(info);
3880 
3881 	info->rx_enabled = false;
3882 	info->rx_restart = false;
3883 }
3884 
3885 static void rx_start(struct slgt_info *info)
3886 {
3887 	unsigned short val;
3888 
3889 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3890 
3891 	/* clear pending rx overrun IRQ */
3892 	wr_reg16(info, SSR, IRQ_RXOVER);
3893 
3894 	/* reset and disable receiver */
3895 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3896 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3897 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3898 
3899 	rdma_reset(info);
3900 	reset_rbufs(info);
3901 
3902 	if (info->rx_pio) {
3903 		/* rx request when rx FIFO not empty */
3904 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3905 		slgt_irq_on(info, IRQ_RXDATA);
3906 		if (info->params.mode == MGSL_MODE_ASYNC) {
3907 			/* enable saving of rx status */
3908 			wr_reg32(info, RDCSR, BIT6);
3909 		}
3910 	} else {
3911 		/* rx request when rx FIFO half full */
3912 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3913 		/* set 1st descriptor address */
3914 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3915 
3916 		if (info->params.mode != MGSL_MODE_ASYNC) {
3917 			/* enable rx DMA and DMA interrupt */
3918 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3919 		} else {
3920 			/* enable saving of rx status, rx DMA and DMA interrupt */
3921 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3922 		}
3923 	}
3924 
3925 	slgt_irq_on(info, IRQ_RXOVER);
3926 
3927 	/* enable receiver */
3928 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3929 
3930 	info->rx_restart = false;
3931 	info->rx_enabled = true;
3932 }
3933 
3934 static void tx_start(struct slgt_info *info)
3935 {
3936 	if (!info->tx_enabled) {
3937 		wr_reg16(info, TCR,
3938 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3939 		info->tx_enabled = true;
3940 	}
3941 
3942 	if (desc_count(info->tbufs[info->tbuf_start])) {
3943 		info->drop_rts_on_tx_done = false;
3944 
3945 		if (info->params.mode != MGSL_MODE_ASYNC) {
3946 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3947 				get_gtsignals(info);
3948 				if (!(info->signals & SerialSignal_RTS)) {
3949 					info->signals |= SerialSignal_RTS;
3950 					set_gtsignals(info);
3951 					info->drop_rts_on_tx_done = true;
3952 				}
3953 			}
3954 
3955 			slgt_irq_off(info, IRQ_TXDATA);
3956 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3957 			/* clear tx idle and underrun status bits */
3958 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3959 		} else {
3960 			slgt_irq_off(info, IRQ_TXDATA);
3961 			slgt_irq_on(info, IRQ_TXIDLE);
3962 			/* clear tx idle status bit */
3963 			wr_reg16(info, SSR, IRQ_TXIDLE);
3964 		}
3965 		/* set 1st descriptor address and start DMA */
3966 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3967 		wr_reg32(info, TDCSR, BIT2 + BIT0);
3968 		info->tx_active = true;
3969 	}
3970 }
3971 
3972 static void tx_stop(struct slgt_info *info)
3973 {
3974 	unsigned short val;
3975 
3976 	del_timer(&info->tx_timer);
3977 
3978 	tdma_reset(info);
3979 
3980 	/* reset and disable transmitter */
3981 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
3982 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
3983 
3984 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
3985 
3986 	/* clear tx idle and underrun status bit */
3987 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3988 
3989 	reset_tbufs(info);
3990 
3991 	info->tx_enabled = false;
3992 	info->tx_active = false;
3993 }
3994 
3995 static void reset_port(struct slgt_info *info)
3996 {
3997 	if (!info->reg_addr)
3998 		return;
3999 
4000 	tx_stop(info);
4001 	rx_stop(info);
4002 
4003 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4004 	set_gtsignals(info);
4005 
4006 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4007 }
4008 
4009 static void reset_adapter(struct slgt_info *info)
4010 {
4011 	int i;
4012 	for (i=0; i < info->port_count; ++i) {
4013 		if (info->port_array[i])
4014 			reset_port(info->port_array[i]);
4015 	}
4016 }
4017 
4018 static void async_mode(struct slgt_info *info)
4019 {
4020   	unsigned short val;
4021 
4022 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4023 	tx_stop(info);
4024 	rx_stop(info);
4025 
4026 	/* TCR (tx control)
4027 	 *
4028 	 * 15..13  mode, 010=async
4029 	 * 12..10  encoding, 000=NRZ
4030 	 * 09      parity enable
4031 	 * 08      1=odd parity, 0=even parity
4032 	 * 07      1=RTS driver control
4033 	 * 06      1=break enable
4034 	 * 05..04  character length
4035 	 *         00=5 bits
4036 	 *         01=6 bits
4037 	 *         10=7 bits
4038 	 *         11=8 bits
4039 	 * 03      0=1 stop bit, 1=2 stop bits
4040 	 * 02      reset
4041 	 * 01      enable
4042 	 * 00      auto-CTS enable
4043 	 */
4044 	val = 0x4000;
4045 
4046 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4047 		val |= BIT7;
4048 
4049 	if (info->params.parity != ASYNC_PARITY_NONE) {
4050 		val |= BIT9;
4051 		if (info->params.parity == ASYNC_PARITY_ODD)
4052 			val |= BIT8;
4053 	}
4054 
4055 	switch (info->params.data_bits)
4056 	{
4057 	case 6: val |= BIT4; break;
4058 	case 7: val |= BIT5; break;
4059 	case 8: val |= BIT5 + BIT4; break;
4060 	}
4061 
4062 	if (info->params.stop_bits != 1)
4063 		val |= BIT3;
4064 
4065 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4066 		val |= BIT0;
4067 
4068 	wr_reg16(info, TCR, val);
4069 
4070 	/* RCR (rx control)
4071 	 *
4072 	 * 15..13  mode, 010=async
4073 	 * 12..10  encoding, 000=NRZ
4074 	 * 09      parity enable
4075 	 * 08      1=odd parity, 0=even parity
4076 	 * 07..06  reserved, must be 0
4077 	 * 05..04  character length
4078 	 *         00=5 bits
4079 	 *         01=6 bits
4080 	 *         10=7 bits
4081 	 *         11=8 bits
4082 	 * 03      reserved, must be zero
4083 	 * 02      reset
4084 	 * 01      enable
4085 	 * 00      auto-DCD enable
4086 	 */
4087 	val = 0x4000;
4088 
4089 	if (info->params.parity != ASYNC_PARITY_NONE) {
4090 		val |= BIT9;
4091 		if (info->params.parity == ASYNC_PARITY_ODD)
4092 			val |= BIT8;
4093 	}
4094 
4095 	switch (info->params.data_bits)
4096 	{
4097 	case 6: val |= BIT4; break;
4098 	case 7: val |= BIT5; break;
4099 	case 8: val |= BIT5 + BIT4; break;
4100 	}
4101 
4102 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4103 		val |= BIT0;
4104 
4105 	wr_reg16(info, RCR, val);
4106 
4107 	/* CCR (clock control)
4108 	 *
4109 	 * 07..05  011 = tx clock source is BRG/16
4110 	 * 04..02  010 = rx clock source is BRG
4111 	 * 01      0 = auxclk disabled
4112 	 * 00      1 = BRG enabled
4113 	 *
4114 	 * 0110 1001
4115 	 */
4116 	wr_reg8(info, CCR, 0x69);
4117 
4118 	msc_set_vcr(info);
4119 
4120 	/* SCR (serial control)
4121 	 *
4122 	 * 15  1=tx req on FIFO half empty
4123 	 * 14  1=rx req on FIFO half full
4124 	 * 13  tx data  IRQ enable
4125 	 * 12  tx idle  IRQ enable
4126 	 * 11  rx break on IRQ enable
4127 	 * 10  rx data  IRQ enable
4128 	 * 09  rx break off IRQ enable
4129 	 * 08  overrun  IRQ enable
4130 	 * 07  DSR      IRQ enable
4131 	 * 06  CTS      IRQ enable
4132 	 * 05  DCD      IRQ enable
4133 	 * 04  RI       IRQ enable
4134 	 * 03  0=16x sampling, 1=8x sampling
4135 	 * 02  1=txd->rxd internal loopback enable
4136 	 * 01  reserved, must be zero
4137 	 * 00  1=master IRQ enable
4138 	 */
4139 	val = BIT15 + BIT14 + BIT0;
4140 	/* JCR[8] : 1 = x8 async mode feature available */
4141 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4142 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4143 	     (info->base_clock % (info->params.data_rate * 16)))) {
4144 		/* use 8x sampling */
4145 		val |= BIT3;
4146 		set_rate(info, info->params.data_rate * 8);
4147 	} else {
4148 		/* use 16x sampling */
4149 		set_rate(info, info->params.data_rate * 16);
4150 	}
4151 	wr_reg16(info, SCR, val);
4152 
4153 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4154 
4155 	if (info->params.loopback)
4156 		enable_loopback(info);
4157 }
4158 
4159 static void sync_mode(struct slgt_info *info)
4160 {
4161 	unsigned short val;
4162 
4163 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4164 	tx_stop(info);
4165 	rx_stop(info);
4166 
4167 	/* TCR (tx control)
4168 	 *
4169 	 * 15..13  mode
4170 	 *         000=HDLC/SDLC
4171 	 *         001=raw bit synchronous
4172 	 *         010=asynchronous/isochronous
4173 	 *         011=monosync byte synchronous
4174 	 *         100=bisync byte synchronous
4175 	 *         101=xsync byte synchronous
4176 	 * 12..10  encoding
4177 	 * 09      CRC enable
4178 	 * 08      CRC32
4179 	 * 07      1=RTS driver control
4180 	 * 06      preamble enable
4181 	 * 05..04  preamble length
4182 	 * 03      share open/close flag
4183 	 * 02      reset
4184 	 * 01      enable
4185 	 * 00      auto-CTS enable
4186 	 */
4187 	val = BIT2;
4188 
4189 	switch(info->params.mode) {
4190 	case MGSL_MODE_XSYNC:
4191 		val |= BIT15 + BIT13;
4192 		break;
4193 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4194 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4195 	case MGSL_MODE_RAW:      val |= BIT13; break;
4196 	}
4197 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4198 		val |= BIT7;
4199 
4200 	switch(info->params.encoding)
4201 	{
4202 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4203 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4204 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4205 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4206 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4207 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4208 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4209 	}
4210 
4211 	switch (info->params.crc_type & HDLC_CRC_MASK)
4212 	{
4213 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4214 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4215 	}
4216 
4217 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4218 		val |= BIT6;
4219 
4220 	switch (info->params.preamble_length)
4221 	{
4222 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4223 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4224 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4225 	}
4226 
4227 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4228 		val |= BIT0;
4229 
4230 	wr_reg16(info, TCR, val);
4231 
4232 	/* TPR (transmit preamble) */
4233 
4234 	switch (info->params.preamble)
4235 	{
4236 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4237 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4238 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4239 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4240 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4241 	default:                          val = 0x7e; break;
4242 	}
4243 	wr_reg8(info, TPR, (unsigned char)val);
4244 
4245 	/* RCR (rx control)
4246 	 *
4247 	 * 15..13  mode
4248 	 *         000=HDLC/SDLC
4249 	 *         001=raw bit synchronous
4250 	 *         010=asynchronous/isochronous
4251 	 *         011=monosync byte synchronous
4252 	 *         100=bisync byte synchronous
4253 	 *         101=xsync byte synchronous
4254 	 * 12..10  encoding
4255 	 * 09      CRC enable
4256 	 * 08      CRC32
4257 	 * 07..03  reserved, must be 0
4258 	 * 02      reset
4259 	 * 01      enable
4260 	 * 00      auto-DCD enable
4261 	 */
4262 	val = 0;
4263 
4264 	switch(info->params.mode) {
4265 	case MGSL_MODE_XSYNC:
4266 		val |= BIT15 + BIT13;
4267 		break;
4268 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4269 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4270 	case MGSL_MODE_RAW:      val |= BIT13; break;
4271 	}
4272 
4273 	switch(info->params.encoding)
4274 	{
4275 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4276 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4277 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4278 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4279 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4280 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4281 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4282 	}
4283 
4284 	switch (info->params.crc_type & HDLC_CRC_MASK)
4285 	{
4286 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4287 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4288 	}
4289 
4290 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4291 		val |= BIT0;
4292 
4293 	wr_reg16(info, RCR, val);
4294 
4295 	/* CCR (clock control)
4296 	 *
4297 	 * 07..05  tx clock source
4298 	 * 04..02  rx clock source
4299 	 * 01      auxclk enable
4300 	 * 00      BRG enable
4301 	 */
4302 	val = 0;
4303 
4304 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4305 	{
4306 		// when RxC source is DPLL, BRG generates 16X DPLL
4307 		// reference clock, so take TxC from BRG/16 to get
4308 		// transmit clock at actual data rate
4309 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4310 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4311 		else
4312 			val |= BIT6;	/* 010, txclk = BRG */
4313 	}
4314 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4315 		val |= BIT7;	/* 100, txclk = DPLL Input */
4316 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4317 		val |= BIT5;	/* 001, txclk = RXC Input */
4318 
4319 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4320 		val |= BIT3;	/* 010, rxclk = BRG */
4321 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4322 		val |= BIT4;	/* 100, rxclk = DPLL */
4323 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4324 		val |= BIT2;	/* 001, rxclk = TXC Input */
4325 
4326 	if (info->params.clock_speed)
4327 		val |= BIT1 + BIT0;
4328 
4329 	wr_reg8(info, CCR, (unsigned char)val);
4330 
4331 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4332 	{
4333 		// program DPLL mode
4334 		switch(info->params.encoding)
4335 		{
4336 		case HDLC_ENCODING_BIPHASE_MARK:
4337 		case HDLC_ENCODING_BIPHASE_SPACE:
4338 			val = BIT7; break;
4339 		case HDLC_ENCODING_BIPHASE_LEVEL:
4340 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4341 			val = BIT7 + BIT6; break;
4342 		default: val = BIT6;	// NRZ encodings
4343 		}
4344 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4345 
4346 		// DPLL requires a 16X reference clock from BRG
4347 		set_rate(info, info->params.clock_speed * 16);
4348 	}
4349 	else
4350 		set_rate(info, info->params.clock_speed);
4351 
4352 	tx_set_idle(info);
4353 
4354 	msc_set_vcr(info);
4355 
4356 	/* SCR (serial control)
4357 	 *
4358 	 * 15  1=tx req on FIFO half empty
4359 	 * 14  1=rx req on FIFO half full
4360 	 * 13  tx data  IRQ enable
4361 	 * 12  tx idle  IRQ enable
4362 	 * 11  underrun IRQ enable
4363 	 * 10  rx data  IRQ enable
4364 	 * 09  rx idle  IRQ enable
4365 	 * 08  overrun  IRQ enable
4366 	 * 07  DSR      IRQ enable
4367 	 * 06  CTS      IRQ enable
4368 	 * 05  DCD      IRQ enable
4369 	 * 04  RI       IRQ enable
4370 	 * 03  reserved, must be zero
4371 	 * 02  1=txd->rxd internal loopback enable
4372 	 * 01  reserved, must be zero
4373 	 * 00  1=master IRQ enable
4374 	 */
4375 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4376 
4377 	if (info->params.loopback)
4378 		enable_loopback(info);
4379 }
4380 
4381 /*
4382  *  set transmit idle mode
4383  */
4384 static void tx_set_idle(struct slgt_info *info)
4385 {
4386 	unsigned char val;
4387 	unsigned short tcr;
4388 
4389 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4390 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4391 	 */
4392 	tcr = rd_reg16(info, TCR);
4393 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4394 		/* disable preamble, set idle size to 16 bits */
4395 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4396 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4397 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4398 	} else if (!(tcr & BIT6)) {
4399 		/* preamble is disabled, set idle size to 8 bits */
4400 		tcr &= ~(BIT5 + BIT4);
4401 	}
4402 	wr_reg16(info, TCR, tcr);
4403 
4404 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4405 		/* LSB of custom tx idle specified in tx idle register */
4406 		val = (unsigned char)(info->idle_mode & 0xff);
4407 	} else {
4408 		/* standard 8 bit idle patterns */
4409 		switch(info->idle_mode)
4410 		{
4411 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4412 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4413 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4414 		case HDLC_TXIDLE_ZEROS:
4415 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4416 		default:                         val = 0xff;
4417 		}
4418 	}
4419 
4420 	wr_reg8(info, TIR, val);
4421 }
4422 
4423 /*
4424  * get state of V24 status (input) signals
4425  */
4426 static void get_gtsignals(struct slgt_info *info)
4427 {
4428 	unsigned short status = rd_reg16(info, SSR);
4429 
4430 	/* clear all serial signals except RTS and DTR */
4431 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4432 
4433 	if (status & BIT3)
4434 		info->signals |= SerialSignal_DSR;
4435 	if (status & BIT2)
4436 		info->signals |= SerialSignal_CTS;
4437 	if (status & BIT1)
4438 		info->signals |= SerialSignal_DCD;
4439 	if (status & BIT0)
4440 		info->signals |= SerialSignal_RI;
4441 }
4442 
4443 /*
4444  * set V.24 Control Register based on current configuration
4445  */
4446 static void msc_set_vcr(struct slgt_info *info)
4447 {
4448 	unsigned char val = 0;
4449 
4450 	/* VCR (V.24 control)
4451 	 *
4452 	 * 07..04  serial IF select
4453 	 * 03      DTR
4454 	 * 02      RTS
4455 	 * 01      LL
4456 	 * 00      RL
4457 	 */
4458 
4459 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4460 	{
4461 	case MGSL_INTERFACE_RS232:
4462 		val |= BIT5; /* 0010 */
4463 		break;
4464 	case MGSL_INTERFACE_V35:
4465 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4466 		break;
4467 	case MGSL_INTERFACE_RS422:
4468 		val |= BIT6; /* 0100 */
4469 		break;
4470 	}
4471 
4472 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4473 		val |= BIT4;
4474 	if (info->signals & SerialSignal_DTR)
4475 		val |= BIT3;
4476 	if (info->signals & SerialSignal_RTS)
4477 		val |= BIT2;
4478 	if (info->if_mode & MGSL_INTERFACE_LL)
4479 		val |= BIT1;
4480 	if (info->if_mode & MGSL_INTERFACE_RL)
4481 		val |= BIT0;
4482 	wr_reg8(info, VCR, val);
4483 }
4484 
4485 /*
4486  * set state of V24 control (output) signals
4487  */
4488 static void set_gtsignals(struct slgt_info *info)
4489 {
4490 	unsigned char val = rd_reg8(info, VCR);
4491 	if (info->signals & SerialSignal_DTR)
4492 		val |= BIT3;
4493 	else
4494 		val &= ~BIT3;
4495 	if (info->signals & SerialSignal_RTS)
4496 		val |= BIT2;
4497 	else
4498 		val &= ~BIT2;
4499 	wr_reg8(info, VCR, val);
4500 }
4501 
4502 /*
4503  * free range of receive DMA buffers (i to last)
4504  */
4505 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4506 {
4507 	int done = 0;
4508 
4509 	while(!done) {
4510 		/* reset current buffer for reuse */
4511 		info->rbufs[i].status = 0;
4512 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4513 		if (i == last)
4514 			done = 1;
4515 		if (++i == info->rbuf_count)
4516 			i = 0;
4517 	}
4518 	info->rbuf_current = i;
4519 }
4520 
4521 /*
4522  * mark all receive DMA buffers as free
4523  */
4524 static void reset_rbufs(struct slgt_info *info)
4525 {
4526 	free_rbufs(info, 0, info->rbuf_count - 1);
4527 	info->rbuf_fill_index = 0;
4528 	info->rbuf_fill_count = 0;
4529 }
4530 
4531 /*
4532  * pass receive HDLC frame to upper layer
4533  *
4534  * return true if frame available, otherwise false
4535  */
4536 static bool rx_get_frame(struct slgt_info *info)
4537 {
4538 	unsigned int start, end;
4539 	unsigned short status;
4540 	unsigned int framesize = 0;
4541 	unsigned long flags;
4542 	struct tty_struct *tty = info->port.tty;
4543 	unsigned char addr_field = 0xff;
4544 	unsigned int crc_size = 0;
4545 
4546 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4547 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4548 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4549 	}
4550 
4551 check_again:
4552 
4553 	framesize = 0;
4554 	addr_field = 0xff;
4555 	start = end = info->rbuf_current;
4556 
4557 	for (;;) {
4558 		if (!desc_complete(info->rbufs[end]))
4559 			goto cleanup;
4560 
4561 		if (framesize == 0 && info->params.addr_filter != 0xff)
4562 			addr_field = info->rbufs[end].buf[0];
4563 
4564 		framesize += desc_count(info->rbufs[end]);
4565 
4566 		if (desc_eof(info->rbufs[end]))
4567 			break;
4568 
4569 		if (++end == info->rbuf_count)
4570 			end = 0;
4571 
4572 		if (end == info->rbuf_current) {
4573 			if (info->rx_enabled){
4574 				spin_lock_irqsave(&info->lock,flags);
4575 				rx_start(info);
4576 				spin_unlock_irqrestore(&info->lock,flags);
4577 			}
4578 			goto cleanup;
4579 		}
4580 	}
4581 
4582 	/* status
4583 	 *
4584 	 * 15      buffer complete
4585 	 * 14..06  reserved
4586 	 * 05..04  residue
4587 	 * 02      eof (end of frame)
4588 	 * 01      CRC error
4589 	 * 00      abort
4590 	 */
4591 	status = desc_status(info->rbufs[end]);
4592 
4593 	/* ignore CRC bit if not using CRC (bit is undefined) */
4594 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4595 		status &= ~BIT1;
4596 
4597 	if (framesize == 0 ||
4598 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4599 		free_rbufs(info, start, end);
4600 		goto check_again;
4601 	}
4602 
4603 	if (framesize < (2 + crc_size) || status & BIT0) {
4604 		info->icount.rxshort++;
4605 		framesize = 0;
4606 	} else if (status & BIT1) {
4607 		info->icount.rxcrc++;
4608 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4609 			framesize = 0;
4610 	}
4611 
4612 #if SYNCLINK_GENERIC_HDLC
4613 	if (framesize == 0) {
4614 		info->netdev->stats.rx_errors++;
4615 		info->netdev->stats.rx_frame_errors++;
4616 	}
4617 #endif
4618 
4619 	DBGBH(("%s rx frame status=%04X size=%d\n",
4620 		info->device_name, status, framesize));
4621 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4622 
4623 	if (framesize) {
4624 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4625 			framesize -= crc_size;
4626 			crc_size = 0;
4627 		}
4628 
4629 		if (framesize > info->max_frame_size + crc_size)
4630 			info->icount.rxlong++;
4631 		else {
4632 			/* copy dma buffer(s) to contiguous temp buffer */
4633 			int copy_count = framesize;
4634 			int i = start;
4635 			unsigned char *p = info->tmp_rbuf;
4636 			info->tmp_rbuf_count = framesize;
4637 
4638 			info->icount.rxok++;
4639 
4640 			while(copy_count) {
4641 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4642 				memcpy(p, info->rbufs[i].buf, partial_count);
4643 				p += partial_count;
4644 				copy_count -= partial_count;
4645 				if (++i == info->rbuf_count)
4646 					i = 0;
4647 			}
4648 
4649 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4650 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4651 				framesize++;
4652 			}
4653 
4654 #if SYNCLINK_GENERIC_HDLC
4655 			if (info->netcount)
4656 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4657 			else
4658 #endif
4659 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4660 		}
4661 	}
4662 	free_rbufs(info, start, end);
4663 	return true;
4664 
4665 cleanup:
4666 	return false;
4667 }
4668 
4669 /*
4670  * pass receive buffer (RAW synchronous mode) to tty layer
4671  * return true if buffer available, otherwise false
4672  */
4673 static bool rx_get_buf(struct slgt_info *info)
4674 {
4675 	unsigned int i = info->rbuf_current;
4676 	unsigned int count;
4677 
4678 	if (!desc_complete(info->rbufs[i]))
4679 		return false;
4680 	count = desc_count(info->rbufs[i]);
4681 	switch(info->params.mode) {
4682 	case MGSL_MODE_MONOSYNC:
4683 	case MGSL_MODE_BISYNC:
4684 	case MGSL_MODE_XSYNC:
4685 		/* ignore residue in byte synchronous modes */
4686 		if (desc_residue(info->rbufs[i]))
4687 			count--;
4688 		break;
4689 	}
4690 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4691 	DBGINFO(("rx_get_buf size=%d\n", count));
4692 	if (count)
4693 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4694 				  info->flag_buf, count);
4695 	free_rbufs(info, i, i);
4696 	return true;
4697 }
4698 
4699 static void reset_tbufs(struct slgt_info *info)
4700 {
4701 	unsigned int i;
4702 	info->tbuf_current = 0;
4703 	for (i=0 ; i < info->tbuf_count ; i++) {
4704 		info->tbufs[i].status = 0;
4705 		info->tbufs[i].count  = 0;
4706 	}
4707 }
4708 
4709 /*
4710  * return number of free transmit DMA buffers
4711  */
4712 static unsigned int free_tbuf_count(struct slgt_info *info)
4713 {
4714 	unsigned int count = 0;
4715 	unsigned int i = info->tbuf_current;
4716 
4717 	do
4718 	{
4719 		if (desc_count(info->tbufs[i]))
4720 			break; /* buffer in use */
4721 		++count;
4722 		if (++i == info->tbuf_count)
4723 			i=0;
4724 	} while (i != info->tbuf_current);
4725 
4726 	/* if tx DMA active, last zero count buffer is in use */
4727 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4728 		--count;
4729 
4730 	return count;
4731 }
4732 
4733 /*
4734  * return number of bytes in unsent transmit DMA buffers
4735  * and the serial controller tx FIFO
4736  */
4737 static unsigned int tbuf_bytes(struct slgt_info *info)
4738 {
4739 	unsigned int total_count = 0;
4740 	unsigned int i = info->tbuf_current;
4741 	unsigned int reg_value;
4742 	unsigned int count;
4743 	unsigned int active_buf_count = 0;
4744 
4745 	/*
4746 	 * Add descriptor counts for all tx DMA buffers.
4747 	 * If count is zero (cleared by DMA controller after read),
4748 	 * the buffer is complete or is actively being read from.
4749 	 *
4750 	 * Record buf_count of last buffer with zero count starting
4751 	 * from current ring position. buf_count is mirror
4752 	 * copy of count and is not cleared by serial controller.
4753 	 * If DMA controller is active, that buffer is actively
4754 	 * being read so add to total.
4755 	 */
4756 	do {
4757 		count = desc_count(info->tbufs[i]);
4758 		if (count)
4759 			total_count += count;
4760 		else if (!total_count)
4761 			active_buf_count = info->tbufs[i].buf_count;
4762 		if (++i == info->tbuf_count)
4763 			i = 0;
4764 	} while (i != info->tbuf_current);
4765 
4766 	/* read tx DMA status register */
4767 	reg_value = rd_reg32(info, TDCSR);
4768 
4769 	/* if tx DMA active, last zero count buffer is in use */
4770 	if (reg_value & BIT0)
4771 		total_count += active_buf_count;
4772 
4773 	/* add tx FIFO count = reg_value[15..8] */
4774 	total_count += (reg_value >> 8) & 0xff;
4775 
4776 	/* if transmitter active add one byte for shift register */
4777 	if (info->tx_active)
4778 		total_count++;
4779 
4780 	return total_count;
4781 }
4782 
4783 /*
4784  * load data into transmit DMA buffer ring and start transmitter if needed
4785  * return true if data accepted, otherwise false (buffers full)
4786  */
4787 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4788 {
4789 	unsigned short count;
4790 	unsigned int i;
4791 	struct slgt_desc *d;
4792 
4793 	/* check required buffer space */
4794 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4795 		return false;
4796 
4797 	DBGDATA(info, buf, size, "tx");
4798 
4799 	/*
4800 	 * copy data to one or more DMA buffers in circular ring
4801 	 * tbuf_start   = first buffer for this data
4802 	 * tbuf_current = next free buffer
4803 	 *
4804 	 * Copy all data before making data visible to DMA controller by
4805 	 * setting descriptor count of the first buffer.
4806 	 * This prevents an active DMA controller from reading the first DMA
4807 	 * buffers of a frame and stopping before the final buffers are filled.
4808 	 */
4809 
4810 	info->tbuf_start = i = info->tbuf_current;
4811 
4812 	while (size) {
4813 		d = &info->tbufs[i];
4814 
4815 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4816 		memcpy(d->buf, buf, count);
4817 
4818 		size -= count;
4819 		buf  += count;
4820 
4821 		/*
4822 		 * set EOF bit for last buffer of HDLC frame or
4823 		 * for every buffer in raw mode
4824 		 */
4825 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4826 		    info->params.mode == MGSL_MODE_RAW)
4827 			set_desc_eof(*d, 1);
4828 		else
4829 			set_desc_eof(*d, 0);
4830 
4831 		/* set descriptor count for all but first buffer */
4832 		if (i != info->tbuf_start)
4833 			set_desc_count(*d, count);
4834 		d->buf_count = count;
4835 
4836 		if (++i == info->tbuf_count)
4837 			i = 0;
4838 	}
4839 
4840 	info->tbuf_current = i;
4841 
4842 	/* set first buffer count to make new data visible to DMA controller */
4843 	d = &info->tbufs[info->tbuf_start];
4844 	set_desc_count(*d, d->buf_count);
4845 
4846 	/* start transmitter if needed and update transmit timeout */
4847 	if (!info->tx_active)
4848 		tx_start(info);
4849 	update_tx_timer(info);
4850 
4851 	return true;
4852 }
4853 
4854 static int register_test(struct slgt_info *info)
4855 {
4856 	static unsigned short patterns[] =
4857 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4858 	static unsigned int count = ARRAY_SIZE(patterns);
4859 	unsigned int i;
4860 	int rc = 0;
4861 
4862 	for (i=0 ; i < count ; i++) {
4863 		wr_reg16(info, TIR, patterns[i]);
4864 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4865 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4866 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4867 			rc = -ENODEV;
4868 			break;
4869 		}
4870 	}
4871 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4872 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4873 	return rc;
4874 }
4875 
4876 static int irq_test(struct slgt_info *info)
4877 {
4878 	unsigned long timeout;
4879 	unsigned long flags;
4880 	struct tty_struct *oldtty = info->port.tty;
4881 	u32 speed = info->params.data_rate;
4882 
4883 	info->params.data_rate = 921600;
4884 	info->port.tty = NULL;
4885 
4886 	spin_lock_irqsave(&info->lock, flags);
4887 	async_mode(info);
4888 	slgt_irq_on(info, IRQ_TXIDLE);
4889 
4890 	/* enable transmitter */
4891 	wr_reg16(info, TCR,
4892 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4893 
4894 	/* write one byte and wait for tx idle */
4895 	wr_reg16(info, TDR, 0);
4896 
4897 	/* assume failure */
4898 	info->init_error = DiagStatus_IrqFailure;
4899 	info->irq_occurred = false;
4900 
4901 	spin_unlock_irqrestore(&info->lock, flags);
4902 
4903 	timeout=100;
4904 	while(timeout-- && !info->irq_occurred)
4905 		msleep_interruptible(10);
4906 
4907 	spin_lock_irqsave(&info->lock,flags);
4908 	reset_port(info);
4909 	spin_unlock_irqrestore(&info->lock,flags);
4910 
4911 	info->params.data_rate = speed;
4912 	info->port.tty = oldtty;
4913 
4914 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4915 	return info->irq_occurred ? 0 : -ENODEV;
4916 }
4917 
4918 static int loopback_test_rx(struct slgt_info *info)
4919 {
4920 	unsigned char *src, *dest;
4921 	int count;
4922 
4923 	if (desc_complete(info->rbufs[0])) {
4924 		count = desc_count(info->rbufs[0]);
4925 		src   = info->rbufs[0].buf;
4926 		dest  = info->tmp_rbuf;
4927 
4928 		for( ; count ; count-=2, src+=2) {
4929 			/* src=data byte (src+1)=status byte */
4930 			if (!(*(src+1) & (BIT9 + BIT8))) {
4931 				*dest = *src;
4932 				dest++;
4933 				info->tmp_rbuf_count++;
4934 			}
4935 		}
4936 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4937 		return 1;
4938 	}
4939 	return 0;
4940 }
4941 
4942 static int loopback_test(struct slgt_info *info)
4943 {
4944 #define TESTFRAMESIZE 20
4945 
4946 	unsigned long timeout;
4947 	u16 count;
4948 	unsigned char buf[TESTFRAMESIZE];
4949 	int rc = -ENODEV;
4950 	unsigned long flags;
4951 
4952 	struct tty_struct *oldtty = info->port.tty;
4953 	MGSL_PARAMS params;
4954 
4955 	memcpy(&params, &info->params, sizeof(params));
4956 
4957 	info->params.mode = MGSL_MODE_ASYNC;
4958 	info->params.data_rate = 921600;
4959 	info->params.loopback = 1;
4960 	info->port.tty = NULL;
4961 
4962 	/* build and send transmit frame */
4963 	for (count = 0; count < TESTFRAMESIZE; ++count)
4964 		buf[count] = (unsigned char)count;
4965 
4966 	info->tmp_rbuf_count = 0;
4967 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4968 
4969 	/* program hardware for HDLC and enabled receiver */
4970 	spin_lock_irqsave(&info->lock,flags);
4971 	async_mode(info);
4972 	rx_start(info);
4973 	tx_load(info, buf, count);
4974 	spin_unlock_irqrestore(&info->lock, flags);
4975 
4976 	/* wait for receive complete */
4977 	for (timeout = 100; timeout; --timeout) {
4978 		msleep_interruptible(10);
4979 		if (loopback_test_rx(info)) {
4980 			rc = 0;
4981 			break;
4982 		}
4983 	}
4984 
4985 	/* verify received frame length and contents */
4986 	if (!rc && (info->tmp_rbuf_count != count ||
4987 		  memcmp(buf, info->tmp_rbuf, count))) {
4988 		rc = -ENODEV;
4989 	}
4990 
4991 	spin_lock_irqsave(&info->lock,flags);
4992 	reset_adapter(info);
4993 	spin_unlock_irqrestore(&info->lock,flags);
4994 
4995 	memcpy(&info->params, &params, sizeof(info->params));
4996 	info->port.tty = oldtty;
4997 
4998 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
4999 	return rc;
5000 }
5001 
5002 static int adapter_test(struct slgt_info *info)
5003 {
5004 	DBGINFO(("testing %s\n", info->device_name));
5005 	if (register_test(info) < 0) {
5006 		printk("register test failure %s addr=%08X\n",
5007 			info->device_name, info->phys_reg_addr);
5008 	} else if (irq_test(info) < 0) {
5009 		printk("IRQ test failure %s IRQ=%d\n",
5010 			info->device_name, info->irq_level);
5011 	} else if (loopback_test(info) < 0) {
5012 		printk("loopback test failure %s\n", info->device_name);
5013 	}
5014 	return info->init_error;
5015 }
5016 
5017 /*
5018  * transmit timeout handler
5019  */
5020 static void tx_timeout(struct timer_list *t)
5021 {
5022 	struct slgt_info *info = from_timer(info, t, tx_timer);
5023 	unsigned long flags;
5024 
5025 	DBGINFO(("%s tx_timeout\n", info->device_name));
5026 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5027 		info->icount.txtimeout++;
5028 	}
5029 	spin_lock_irqsave(&info->lock,flags);
5030 	tx_stop(info);
5031 	spin_unlock_irqrestore(&info->lock,flags);
5032 
5033 #if SYNCLINK_GENERIC_HDLC
5034 	if (info->netcount)
5035 		hdlcdev_tx_done(info);
5036 	else
5037 #endif
5038 		bh_transmit(info);
5039 }
5040 
5041 /*
5042  * receive buffer polling timer
5043  */
5044 static void rx_timeout(struct timer_list *t)
5045 {
5046 	struct slgt_info *info = from_timer(info, t, rx_timer);
5047 	unsigned long flags;
5048 
5049 	DBGINFO(("%s rx_timeout\n", info->device_name));
5050 	spin_lock_irqsave(&info->lock, flags);
5051 	info->pending_bh |= BH_RECEIVE;
5052 	spin_unlock_irqrestore(&info->lock, flags);
5053 	bh_handler(&info->task);
5054 }
5055 
5056