xref: /openbmc/linux/drivers/tty/synclink_gt.c (revision e40573a4)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22 
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36 
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44 
45 
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74 
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80 
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86 
87 /*
88  * module identification
89  */
90 static char *driver_name     = "SyncLink GT";
91 static char *slgt_driver_name = "synclink_gt";
92 static char *tty_dev_prefix  = "ttySLG";
93 MODULE_LICENSE("GPL");
94 #define MGSL_MAGIC 0x5401
95 #define MAX_DEVICES 32
96 
97 static const struct pci_device_id pci_table[] = {
98 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
102 	{0,}, /* terminate list */
103 };
104 MODULE_DEVICE_TABLE(pci, pci_table);
105 
106 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
107 static void remove_one(struct pci_dev *dev);
108 static struct pci_driver pci_driver = {
109 	.name		= "synclink_gt",
110 	.id_table	= pci_table,
111 	.probe		= init_one,
112 	.remove		= remove_one,
113 };
114 
115 static bool pci_registered;
116 
117 /*
118  * module configuration and status
119  */
120 static struct slgt_info *slgt_device_list;
121 static int slgt_device_count;
122 
123 static int ttymajor;
124 static int debug_level;
125 static int maxframe[MAX_DEVICES];
126 
127 module_param(ttymajor, int, 0);
128 module_param(debug_level, int, 0);
129 module_param_array(maxframe, int, NULL, 0);
130 
131 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
132 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
133 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
134 
135 /*
136  * tty support and callbacks
137  */
138 static struct tty_driver *serial_driver;
139 
140 static void wait_until_sent(struct tty_struct *tty, int timeout);
141 static void flush_buffer(struct tty_struct *tty);
142 static void tx_release(struct tty_struct *tty);
143 
144 /*
145  * generic HDLC support
146  */
147 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
148 
149 
150 /*
151  * device specific structures, macros and functions
152  */
153 
154 #define SLGT_MAX_PORTS 4
155 #define SLGT_REG_SIZE  256
156 
157 /*
158  * conditional wait facility
159  */
160 struct cond_wait {
161 	struct cond_wait *next;
162 	wait_queue_head_t q;
163 	wait_queue_entry_t wait;
164 	unsigned int data;
165 };
166 static void flush_cond_wait(struct cond_wait **head);
167 
168 /*
169  * DMA buffer descriptor and access macros
170  */
171 struct slgt_desc
172 {
173 	__le16 count;
174 	__le16 status;
175 	__le32 pbuf;  /* physical address of data buffer */
176 	__le32 next;  /* physical address of next descriptor */
177 
178 	/* driver book keeping */
179 	char *buf;          /* virtual  address of data buffer */
180     	unsigned int pdesc; /* physical address of this descriptor */
181 	dma_addr_t buf_dma_addr;
182 	unsigned short buf_count;
183 };
184 
185 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
186 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
187 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
188 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
189 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
190 #define desc_count(a)      (le16_to_cpu((a).count))
191 #define desc_status(a)     (le16_to_cpu((a).status))
192 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
193 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
194 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
195 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
196 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
197 
198 struct _input_signal_events {
199 	int ri_up;
200 	int ri_down;
201 	int dsr_up;
202 	int dsr_down;
203 	int dcd_up;
204 	int dcd_down;
205 	int cts_up;
206 	int cts_down;
207 };
208 
209 /*
210  * device instance data structure
211  */
212 struct slgt_info {
213 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
214 	struct tty_port port;
215 
216 	struct slgt_info *next_device;	/* device list link */
217 
218 	int magic;
219 
220 	char device_name[25];
221 	struct pci_dev *pdev;
222 
223 	int port_count;  /* count of ports on adapter */
224 	int adapter_num; /* adapter instance number */
225 	int port_num;    /* port instance number */
226 
227 	/* array of pointers to port contexts on this adapter */
228 	struct slgt_info *port_array[SLGT_MAX_PORTS];
229 
230 	int			line;		/* tty line instance number */
231 
232 	struct mgsl_icount	icount;
233 
234 	int			timeout;
235 	int			x_char;		/* xon/xoff character */
236 	unsigned int		read_status_mask;
237 	unsigned int 		ignore_status_mask;
238 
239 	wait_queue_head_t	status_event_wait_q;
240 	wait_queue_head_t	event_wait_q;
241 	struct timer_list	tx_timer;
242 	struct timer_list	rx_timer;
243 
244 	unsigned int            gpio_present;
245 	struct cond_wait        *gpio_wait_q;
246 
247 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
248 
249 	struct work_struct task;
250 	u32 pending_bh;
251 	bool bh_requested;
252 	bool bh_running;
253 
254 	int isr_overflow;
255 	bool irq_requested;	/* true if IRQ requested */
256 	bool irq_occurred;	/* for diagnostics use */
257 
258 	/* device configuration */
259 
260 	unsigned int bus_type;
261 	unsigned int irq_level;
262 	unsigned long irq_flags;
263 
264 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
265 	u32 phys_reg_addr;
266 	bool reg_addr_requested;
267 
268 	MGSL_PARAMS params;       /* communications parameters */
269 	u32 idle_mode;
270 	u32 max_frame_size;       /* as set by device config */
271 
272 	unsigned int rbuf_fill_level;
273 	unsigned int rx_pio;
274 	unsigned int if_mode;
275 	unsigned int base_clock;
276 	unsigned int xsync;
277 	unsigned int xctrl;
278 
279 	/* device status */
280 
281 	bool rx_enabled;
282 	bool rx_restart;
283 
284 	bool tx_enabled;
285 	bool tx_active;
286 
287 	unsigned char signals;    /* serial signal states */
288 	int init_error;  /* initialization error */
289 
290 	unsigned char *tx_buf;
291 	int tx_count;
292 
293 	char *flag_buf;
294 	bool drop_rts_on_tx_done;
295 	struct	_input_signal_events	input_signal_events;
296 
297 	int dcd_chkcount;	/* check counts to prevent */
298 	int cts_chkcount;	/* too many IRQs if a signal */
299 	int dsr_chkcount;	/* is floating */
300 	int ri_chkcount;
301 
302 	char *bufs;		/* virtual address of DMA buffer lists */
303 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
304 
305 	unsigned int rbuf_count;
306 	struct slgt_desc *rbufs;
307 	unsigned int rbuf_current;
308 	unsigned int rbuf_index;
309 	unsigned int rbuf_fill_index;
310 	unsigned short rbuf_fill_count;
311 
312 	unsigned int tbuf_count;
313 	struct slgt_desc *tbufs;
314 	unsigned int tbuf_current;
315 	unsigned int tbuf_start;
316 
317 	unsigned char *tmp_rbuf;
318 	unsigned int tmp_rbuf_count;
319 
320 	/* SPPP/Cisco HDLC device parts */
321 
322 	int netcount;
323 	spinlock_t netlock;
324 #if SYNCLINK_GENERIC_HDLC
325 	struct net_device *netdev;
326 #endif
327 
328 };
329 
330 static MGSL_PARAMS default_params = {
331 	.mode            = MGSL_MODE_HDLC,
332 	.loopback        = 0,
333 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
334 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
335 	.clock_speed     = 0,
336 	.addr_filter     = 0xff,
337 	.crc_type        = HDLC_CRC_16_CCITT,
338 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
339 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
340 	.data_rate       = 9600,
341 	.data_bits       = 8,
342 	.stop_bits       = 1,
343 	.parity          = ASYNC_PARITY_NONE
344 };
345 
346 
347 #define BH_RECEIVE  1
348 #define BH_TRANSMIT 2
349 #define BH_STATUS   4
350 #define IO_PIN_SHUTDOWN_LIMIT 100
351 
352 #define DMABUFSIZE 256
353 #define DESC_LIST_SIZE 4096
354 
355 #define MASK_PARITY  BIT1
356 #define MASK_FRAMING BIT0
357 #define MASK_BREAK   BIT14
358 #define MASK_OVERRUN BIT4
359 
360 #define GSR   0x00 /* global status */
361 #define JCR   0x04 /* JTAG control */
362 #define IODR  0x08 /* GPIO direction */
363 #define IOER  0x0c /* GPIO interrupt enable */
364 #define IOVR  0x10 /* GPIO value */
365 #define IOSR  0x14 /* GPIO interrupt status */
366 #define TDR   0x80 /* tx data */
367 #define RDR   0x80 /* rx data */
368 #define TCR   0x82 /* tx control */
369 #define TIR   0x84 /* tx idle */
370 #define TPR   0x85 /* tx preamble */
371 #define RCR   0x86 /* rx control */
372 #define VCR   0x88 /* V.24 control */
373 #define CCR   0x89 /* clock control */
374 #define BDR   0x8a /* baud divisor */
375 #define SCR   0x8c /* serial control */
376 #define SSR   0x8e /* serial status */
377 #define RDCSR 0x90 /* rx DMA control/status */
378 #define TDCSR 0x94 /* tx DMA control/status */
379 #define RDDAR 0x98 /* rx DMA descriptor address */
380 #define TDDAR 0x9c /* tx DMA descriptor address */
381 #define XSR   0x40 /* extended sync pattern */
382 #define XCR   0x44 /* extended control */
383 
384 #define RXIDLE      BIT14
385 #define RXBREAK     BIT14
386 #define IRQ_TXDATA  BIT13
387 #define IRQ_TXIDLE  BIT12
388 #define IRQ_TXUNDER BIT11 /* HDLC */
389 #define IRQ_RXDATA  BIT10
390 #define IRQ_RXIDLE  BIT9  /* HDLC */
391 #define IRQ_RXBREAK BIT9  /* async */
392 #define IRQ_RXOVER  BIT8
393 #define IRQ_DSR     BIT7
394 #define IRQ_CTS     BIT6
395 #define IRQ_DCD     BIT5
396 #define IRQ_RI      BIT4
397 #define IRQ_ALL     0x3ff0
398 #define IRQ_MASTER  BIT0
399 
400 #define slgt_irq_on(info, mask) \
401 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
402 #define slgt_irq_off(info, mask) \
403 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
404 
405 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
406 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
407 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
408 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
409 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
410 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
411 
412 static void  msc_set_vcr(struct slgt_info *info);
413 
414 static int  startup(struct slgt_info *info);
415 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
416 static void shutdown(struct slgt_info *info);
417 static void program_hw(struct slgt_info *info);
418 static void change_params(struct slgt_info *info);
419 
420 static int  adapter_test(struct slgt_info *info);
421 
422 static void reset_port(struct slgt_info *info);
423 static void async_mode(struct slgt_info *info);
424 static void sync_mode(struct slgt_info *info);
425 
426 static void rx_stop(struct slgt_info *info);
427 static void rx_start(struct slgt_info *info);
428 static void reset_rbufs(struct slgt_info *info);
429 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
430 static bool rx_get_frame(struct slgt_info *info);
431 static bool rx_get_buf(struct slgt_info *info);
432 
433 static void tx_start(struct slgt_info *info);
434 static void tx_stop(struct slgt_info *info);
435 static void tx_set_idle(struct slgt_info *info);
436 static unsigned int tbuf_bytes(struct slgt_info *info);
437 static void reset_tbufs(struct slgt_info *info);
438 static void tdma_reset(struct slgt_info *info);
439 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
440 
441 static void get_gtsignals(struct slgt_info *info);
442 static void set_gtsignals(struct slgt_info *info);
443 static void set_rate(struct slgt_info *info, u32 data_rate);
444 
445 static void bh_transmit(struct slgt_info *info);
446 static void isr_txeom(struct slgt_info *info, unsigned short status);
447 
448 static void tx_timeout(struct timer_list *t);
449 static void rx_timeout(struct timer_list *t);
450 
451 /*
452  * ioctl handlers
453  */
454 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
455 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
456 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
457 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
458 static int  set_txidle(struct slgt_info *info, int idle_mode);
459 static int  tx_enable(struct slgt_info *info, int enable);
460 static int  tx_abort(struct slgt_info *info);
461 static int  rx_enable(struct slgt_info *info, int enable);
462 static int  modem_input_wait(struct slgt_info *info,int arg);
463 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
464 static int  get_interface(struct slgt_info *info, int __user *if_mode);
465 static int  set_interface(struct slgt_info *info, int if_mode);
466 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
467 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
468 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
469 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
470 static int  set_xsync(struct slgt_info *info, int if_mode);
471 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
472 static int  set_xctrl(struct slgt_info *info, int if_mode);
473 
474 /*
475  * driver functions
476  */
477 static void release_resources(struct slgt_info *info);
478 
479 /*
480  * DEBUG OUTPUT CODE
481  */
482 #ifndef DBGINFO
483 #define DBGINFO(fmt)
484 #endif
485 #ifndef DBGERR
486 #define DBGERR(fmt)
487 #endif
488 #ifndef DBGBH
489 #define DBGBH(fmt)
490 #endif
491 #ifndef DBGISR
492 #define DBGISR(fmt)
493 #endif
494 
495 #ifdef DBGDATA
496 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
497 {
498 	int i;
499 	int linecount;
500 	printk("%s %s data:\n",info->device_name, label);
501 	while(count) {
502 		linecount = (count > 16) ? 16 : count;
503 		for(i=0; i < linecount; i++)
504 			printk("%02X ",(unsigned char)data[i]);
505 		for(;i<17;i++)
506 			printk("   ");
507 		for(i=0;i<linecount;i++) {
508 			if (data[i]>=040 && data[i]<=0176)
509 				printk("%c",data[i]);
510 			else
511 				printk(".");
512 		}
513 		printk("\n");
514 		data  += linecount;
515 		count -= linecount;
516 	}
517 }
518 #else
519 #define DBGDATA(info, buf, size, label)
520 #endif
521 
522 #ifdef DBGTBUF
523 static void dump_tbufs(struct slgt_info *info)
524 {
525 	int i;
526 	printk("tbuf_current=%d\n", info->tbuf_current);
527 	for (i=0 ; i < info->tbuf_count ; i++) {
528 		printk("%d: count=%04X status=%04X\n",
529 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
530 	}
531 }
532 #else
533 #define DBGTBUF(info)
534 #endif
535 
536 #ifdef DBGRBUF
537 static void dump_rbufs(struct slgt_info *info)
538 {
539 	int i;
540 	printk("rbuf_current=%d\n", info->rbuf_current);
541 	for (i=0 ; i < info->rbuf_count ; i++) {
542 		printk("%d: count=%04X status=%04X\n",
543 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
544 	}
545 }
546 #else
547 #define DBGRBUF(info)
548 #endif
549 
550 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
551 {
552 #ifdef SANITY_CHECK
553 	if (!info) {
554 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
555 		return 1;
556 	}
557 	if (info->magic != MGSL_MAGIC) {
558 		printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
559 		return 1;
560 	}
561 #else
562 	if (!info)
563 		return 1;
564 #endif
565 	return 0;
566 }
567 
568 /*
569  * line discipline callback wrappers
570  *
571  * The wrappers maintain line discipline references
572  * while calling into the line discipline.
573  *
574  * ldisc_receive_buf  - pass receive data to line discipline
575  */
576 static void ldisc_receive_buf(struct tty_struct *tty,
577 			      const __u8 *data, char *flags, int count)
578 {
579 	struct tty_ldisc *ld;
580 	if (!tty)
581 		return;
582 	ld = tty_ldisc_ref(tty);
583 	if (ld) {
584 		if (ld->ops->receive_buf)
585 			ld->ops->receive_buf(tty, data, flags, count);
586 		tty_ldisc_deref(ld);
587 	}
588 }
589 
590 /* tty callbacks */
591 
592 static int open(struct tty_struct *tty, struct file *filp)
593 {
594 	struct slgt_info *info;
595 	int retval, line;
596 	unsigned long flags;
597 
598 	line = tty->index;
599 	if (line >= slgt_device_count) {
600 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
601 		return -ENODEV;
602 	}
603 
604 	info = slgt_device_list;
605 	while(info && info->line != line)
606 		info = info->next_device;
607 	if (sanity_check(info, tty->name, "open"))
608 		return -ENODEV;
609 	if (info->init_error) {
610 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
611 		return -ENODEV;
612 	}
613 
614 	tty->driver_data = info;
615 	info->port.tty = tty;
616 
617 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
618 
619 	mutex_lock(&info->port.mutex);
620 
621 	spin_lock_irqsave(&info->netlock, flags);
622 	if (info->netcount) {
623 		retval = -EBUSY;
624 		spin_unlock_irqrestore(&info->netlock, flags);
625 		mutex_unlock(&info->port.mutex);
626 		goto cleanup;
627 	}
628 	info->port.count++;
629 	spin_unlock_irqrestore(&info->netlock, flags);
630 
631 	if (info->port.count == 1) {
632 		/* 1st open on this device, init hardware */
633 		retval = startup(info);
634 		if (retval < 0) {
635 			mutex_unlock(&info->port.mutex);
636 			goto cleanup;
637 		}
638 	}
639 	mutex_unlock(&info->port.mutex);
640 	retval = block_til_ready(tty, filp, info);
641 	if (retval) {
642 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
643 		goto cleanup;
644 	}
645 
646 	retval = 0;
647 
648 cleanup:
649 	if (retval) {
650 		if (tty->count == 1)
651 			info->port.tty = NULL; /* tty layer will release tty struct */
652 		if(info->port.count)
653 			info->port.count--;
654 	}
655 
656 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
657 	return retval;
658 }
659 
660 static void close(struct tty_struct *tty, struct file *filp)
661 {
662 	struct slgt_info *info = tty->driver_data;
663 
664 	if (sanity_check(info, tty->name, "close"))
665 		return;
666 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
667 
668 	if (tty_port_close_start(&info->port, tty, filp) == 0)
669 		goto cleanup;
670 
671 	mutex_lock(&info->port.mutex);
672 	if (tty_port_initialized(&info->port))
673  		wait_until_sent(tty, info->timeout);
674 	flush_buffer(tty);
675 	tty_ldisc_flush(tty);
676 
677 	shutdown(info);
678 	mutex_unlock(&info->port.mutex);
679 
680 	tty_port_close_end(&info->port, tty);
681 	info->port.tty = NULL;
682 cleanup:
683 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
684 }
685 
686 static void hangup(struct tty_struct *tty)
687 {
688 	struct slgt_info *info = tty->driver_data;
689 	unsigned long flags;
690 
691 	if (sanity_check(info, tty->name, "hangup"))
692 		return;
693 	DBGINFO(("%s hangup\n", info->device_name));
694 
695 	flush_buffer(tty);
696 
697 	mutex_lock(&info->port.mutex);
698 	shutdown(info);
699 
700 	spin_lock_irqsave(&info->port.lock, flags);
701 	info->port.count = 0;
702 	info->port.tty = NULL;
703 	spin_unlock_irqrestore(&info->port.lock, flags);
704 	tty_port_set_active(&info->port, 0);
705 	mutex_unlock(&info->port.mutex);
706 
707 	wake_up_interruptible(&info->port.open_wait);
708 }
709 
710 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
711 {
712 	struct slgt_info *info = tty->driver_data;
713 	unsigned long flags;
714 
715 	DBGINFO(("%s set_termios\n", tty->driver->name));
716 
717 	change_params(info);
718 
719 	/* Handle transition to B0 status */
720 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
721 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
722 		spin_lock_irqsave(&info->lock,flags);
723 		set_gtsignals(info);
724 		spin_unlock_irqrestore(&info->lock,flags);
725 	}
726 
727 	/* Handle transition away from B0 status */
728 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
729 		info->signals |= SerialSignal_DTR;
730 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
731 			info->signals |= SerialSignal_RTS;
732 		spin_lock_irqsave(&info->lock,flags);
733 	 	set_gtsignals(info);
734 		spin_unlock_irqrestore(&info->lock,flags);
735 	}
736 
737 	/* Handle turning off CRTSCTS */
738 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
739 		tty->hw_stopped = 0;
740 		tx_release(tty);
741 	}
742 }
743 
744 static void update_tx_timer(struct slgt_info *info)
745 {
746 	/*
747 	 * use worst case speed of 1200bps to calculate transmit timeout
748 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
749 	 */
750 	if (info->params.mode == MGSL_MODE_HDLC) {
751 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
752 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
753 	}
754 }
755 
756 static int write(struct tty_struct *tty,
757 		 const unsigned char *buf, int count)
758 {
759 	int ret = 0;
760 	struct slgt_info *info = tty->driver_data;
761 	unsigned long flags;
762 
763 	if (sanity_check(info, tty->name, "write"))
764 		return -EIO;
765 
766 	DBGINFO(("%s write count=%d\n", info->device_name, count));
767 
768 	if (!info->tx_buf || (count > info->max_frame_size))
769 		return -EIO;
770 
771 	if (!count || tty->flow.stopped || tty->hw_stopped)
772 		return 0;
773 
774 	spin_lock_irqsave(&info->lock, flags);
775 
776 	if (info->tx_count) {
777 		/* send accumulated data from send_char() */
778 		if (!tx_load(info, info->tx_buf, info->tx_count))
779 			goto cleanup;
780 		info->tx_count = 0;
781 	}
782 
783 	if (tx_load(info, buf, count))
784 		ret = count;
785 
786 cleanup:
787 	spin_unlock_irqrestore(&info->lock, flags);
788 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
789 	return ret;
790 }
791 
792 static int put_char(struct tty_struct *tty, unsigned char ch)
793 {
794 	struct slgt_info *info = tty->driver_data;
795 	unsigned long flags;
796 	int ret = 0;
797 
798 	if (sanity_check(info, tty->name, "put_char"))
799 		return 0;
800 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
801 	if (!info->tx_buf)
802 		return 0;
803 	spin_lock_irqsave(&info->lock,flags);
804 	if (info->tx_count < info->max_frame_size) {
805 		info->tx_buf[info->tx_count++] = ch;
806 		ret = 1;
807 	}
808 	spin_unlock_irqrestore(&info->lock,flags);
809 	return ret;
810 }
811 
812 static void send_xchar(struct tty_struct *tty, char ch)
813 {
814 	struct slgt_info *info = tty->driver_data;
815 	unsigned long flags;
816 
817 	if (sanity_check(info, tty->name, "send_xchar"))
818 		return;
819 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
820 	info->x_char = ch;
821 	if (ch) {
822 		spin_lock_irqsave(&info->lock,flags);
823 		if (!info->tx_enabled)
824 		 	tx_start(info);
825 		spin_unlock_irqrestore(&info->lock,flags);
826 	}
827 }
828 
829 static void wait_until_sent(struct tty_struct *tty, int timeout)
830 {
831 	struct slgt_info *info = tty->driver_data;
832 	unsigned long orig_jiffies, char_time;
833 
834 	if (!info )
835 		return;
836 	if (sanity_check(info, tty->name, "wait_until_sent"))
837 		return;
838 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
839 	if (!tty_port_initialized(&info->port))
840 		goto exit;
841 
842 	orig_jiffies = jiffies;
843 
844 	/* Set check interval to 1/5 of estimated time to
845 	 * send a character, and make it at least 1. The check
846 	 * interval should also be less than the timeout.
847 	 * Note: use tight timings here to satisfy the NIST-PCTS.
848 	 */
849 
850 	if (info->params.data_rate) {
851 	       	char_time = info->timeout/(32 * 5);
852 		if (!char_time)
853 			char_time++;
854 	} else
855 		char_time = 1;
856 
857 	if (timeout)
858 		char_time = min_t(unsigned long, char_time, timeout);
859 
860 	while (info->tx_active) {
861 		msleep_interruptible(jiffies_to_msecs(char_time));
862 		if (signal_pending(current))
863 			break;
864 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
865 			break;
866 	}
867 exit:
868 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
869 }
870 
871 static unsigned int write_room(struct tty_struct *tty)
872 {
873 	struct slgt_info *info = tty->driver_data;
874 	unsigned int ret;
875 
876 	if (sanity_check(info, tty->name, "write_room"))
877 		return 0;
878 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
879 	DBGINFO(("%s write_room=%u\n", info->device_name, ret));
880 	return ret;
881 }
882 
883 static void flush_chars(struct tty_struct *tty)
884 {
885 	struct slgt_info *info = tty->driver_data;
886 	unsigned long flags;
887 
888 	if (sanity_check(info, tty->name, "flush_chars"))
889 		return;
890 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
891 
892 	if (info->tx_count <= 0 || tty->flow.stopped ||
893 	    tty->hw_stopped || !info->tx_buf)
894 		return;
895 
896 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
897 
898 	spin_lock_irqsave(&info->lock,flags);
899 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
900 		info->tx_count = 0;
901 	spin_unlock_irqrestore(&info->lock,flags);
902 }
903 
904 static void flush_buffer(struct tty_struct *tty)
905 {
906 	struct slgt_info *info = tty->driver_data;
907 	unsigned long flags;
908 
909 	if (sanity_check(info, tty->name, "flush_buffer"))
910 		return;
911 	DBGINFO(("%s flush_buffer\n", info->device_name));
912 
913 	spin_lock_irqsave(&info->lock, flags);
914 	info->tx_count = 0;
915 	spin_unlock_irqrestore(&info->lock, flags);
916 
917 	tty_wakeup(tty);
918 }
919 
920 /*
921  * throttle (stop) transmitter
922  */
923 static void tx_hold(struct tty_struct *tty)
924 {
925 	struct slgt_info *info = tty->driver_data;
926 	unsigned long flags;
927 
928 	if (sanity_check(info, tty->name, "tx_hold"))
929 		return;
930 	DBGINFO(("%s tx_hold\n", info->device_name));
931 	spin_lock_irqsave(&info->lock,flags);
932 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
933 	 	tx_stop(info);
934 	spin_unlock_irqrestore(&info->lock,flags);
935 }
936 
937 /*
938  * release (start) transmitter
939  */
940 static void tx_release(struct tty_struct *tty)
941 {
942 	struct slgt_info *info = tty->driver_data;
943 	unsigned long flags;
944 
945 	if (sanity_check(info, tty->name, "tx_release"))
946 		return;
947 	DBGINFO(("%s tx_release\n", info->device_name));
948 	spin_lock_irqsave(&info->lock, flags);
949 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
950 		info->tx_count = 0;
951 	spin_unlock_irqrestore(&info->lock, flags);
952 }
953 
954 /*
955  * Service an IOCTL request
956  *
957  * Arguments
958  *
959  * 	tty	pointer to tty instance data
960  * 	cmd	IOCTL command code
961  * 	arg	command argument/context
962  *
963  * Return 0 if success, otherwise error code
964  */
965 static int ioctl(struct tty_struct *tty,
966 		 unsigned int cmd, unsigned long arg)
967 {
968 	struct slgt_info *info = tty->driver_data;
969 	void __user *argp = (void __user *)arg;
970 	int ret;
971 
972 	if (sanity_check(info, tty->name, "ioctl"))
973 		return -ENODEV;
974 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
975 
976 	if (cmd != TIOCMIWAIT) {
977 		if (tty_io_error(tty))
978 		    return -EIO;
979 	}
980 
981 	switch (cmd) {
982 	case MGSL_IOCWAITEVENT:
983 		return wait_mgsl_event(info, argp);
984 	case TIOCMIWAIT:
985 		return modem_input_wait(info,(int)arg);
986 	case MGSL_IOCSGPIO:
987 		return set_gpio(info, argp);
988 	case MGSL_IOCGGPIO:
989 		return get_gpio(info, argp);
990 	case MGSL_IOCWAITGPIO:
991 		return wait_gpio(info, argp);
992 	case MGSL_IOCGXSYNC:
993 		return get_xsync(info, argp);
994 	case MGSL_IOCSXSYNC:
995 		return set_xsync(info, (int)arg);
996 	case MGSL_IOCGXCTRL:
997 		return get_xctrl(info, argp);
998 	case MGSL_IOCSXCTRL:
999 		return set_xctrl(info, (int)arg);
1000 	}
1001 	mutex_lock(&info->port.mutex);
1002 	switch (cmd) {
1003 	case MGSL_IOCGPARAMS:
1004 		ret = get_params(info, argp);
1005 		break;
1006 	case MGSL_IOCSPARAMS:
1007 		ret = set_params(info, argp);
1008 		break;
1009 	case MGSL_IOCGTXIDLE:
1010 		ret = get_txidle(info, argp);
1011 		break;
1012 	case MGSL_IOCSTXIDLE:
1013 		ret = set_txidle(info, (int)arg);
1014 		break;
1015 	case MGSL_IOCTXENABLE:
1016 		ret = tx_enable(info, (int)arg);
1017 		break;
1018 	case MGSL_IOCRXENABLE:
1019 		ret = rx_enable(info, (int)arg);
1020 		break;
1021 	case MGSL_IOCTXABORT:
1022 		ret = tx_abort(info);
1023 		break;
1024 	case MGSL_IOCGSTATS:
1025 		ret = get_stats(info, argp);
1026 		break;
1027 	case MGSL_IOCGIF:
1028 		ret = get_interface(info, argp);
1029 		break;
1030 	case MGSL_IOCSIF:
1031 		ret = set_interface(info,(int)arg);
1032 		break;
1033 	default:
1034 		ret = -ENOIOCTLCMD;
1035 	}
1036 	mutex_unlock(&info->port.mutex);
1037 	return ret;
1038 }
1039 
1040 static int get_icount(struct tty_struct *tty,
1041 				struct serial_icounter_struct *icount)
1042 
1043 {
1044 	struct slgt_info *info = tty->driver_data;
1045 	struct mgsl_icount cnow;	/* kernel counter temps */
1046 	unsigned long flags;
1047 
1048 	spin_lock_irqsave(&info->lock,flags);
1049 	cnow = info->icount;
1050 	spin_unlock_irqrestore(&info->lock,flags);
1051 
1052 	icount->cts = cnow.cts;
1053 	icount->dsr = cnow.dsr;
1054 	icount->rng = cnow.rng;
1055 	icount->dcd = cnow.dcd;
1056 	icount->rx = cnow.rx;
1057 	icount->tx = cnow.tx;
1058 	icount->frame = cnow.frame;
1059 	icount->overrun = cnow.overrun;
1060 	icount->parity = cnow.parity;
1061 	icount->brk = cnow.brk;
1062 	icount->buf_overrun = cnow.buf_overrun;
1063 
1064 	return 0;
1065 }
1066 
1067 /*
1068  * support for 32 bit ioctl calls on 64 bit systems
1069  */
1070 #ifdef CONFIG_COMPAT
1071 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1072 {
1073 	struct MGSL_PARAMS32 tmp_params;
1074 
1075 	DBGINFO(("%s get_params32\n", info->device_name));
1076 	memset(&tmp_params, 0, sizeof(tmp_params));
1077 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1078 	tmp_params.loopback        = info->params.loopback;
1079 	tmp_params.flags           = info->params.flags;
1080 	tmp_params.encoding        = info->params.encoding;
1081 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1082 	tmp_params.addr_filter     = info->params.addr_filter;
1083 	tmp_params.crc_type        = info->params.crc_type;
1084 	tmp_params.preamble_length = info->params.preamble_length;
1085 	tmp_params.preamble        = info->params.preamble;
1086 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1087 	tmp_params.data_bits       = info->params.data_bits;
1088 	tmp_params.stop_bits       = info->params.stop_bits;
1089 	tmp_params.parity          = info->params.parity;
1090 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1091 		return -EFAULT;
1092 	return 0;
1093 }
1094 
1095 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1096 {
1097 	struct MGSL_PARAMS32 tmp_params;
1098 
1099 	DBGINFO(("%s set_params32\n", info->device_name));
1100 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1101 		return -EFAULT;
1102 
1103 	spin_lock(&info->lock);
1104 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1105 		info->base_clock = tmp_params.clock_speed;
1106 	} else {
1107 		info->params.mode            = tmp_params.mode;
1108 		info->params.loopback        = tmp_params.loopback;
1109 		info->params.flags           = tmp_params.flags;
1110 		info->params.encoding        = tmp_params.encoding;
1111 		info->params.clock_speed     = tmp_params.clock_speed;
1112 		info->params.addr_filter     = tmp_params.addr_filter;
1113 		info->params.crc_type        = tmp_params.crc_type;
1114 		info->params.preamble_length = tmp_params.preamble_length;
1115 		info->params.preamble        = tmp_params.preamble;
1116 		info->params.data_rate       = tmp_params.data_rate;
1117 		info->params.data_bits       = tmp_params.data_bits;
1118 		info->params.stop_bits       = tmp_params.stop_bits;
1119 		info->params.parity          = tmp_params.parity;
1120 	}
1121 	spin_unlock(&info->lock);
1122 
1123 	program_hw(info);
1124 
1125 	return 0;
1126 }
1127 
1128 static long slgt_compat_ioctl(struct tty_struct *tty,
1129 			 unsigned int cmd, unsigned long arg)
1130 {
1131 	struct slgt_info *info = tty->driver_data;
1132 	int rc;
1133 
1134 	if (sanity_check(info, tty->name, "compat_ioctl"))
1135 		return -ENODEV;
1136 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1137 
1138 	switch (cmd) {
1139 	case MGSL_IOCSPARAMS32:
1140 		rc = set_params32(info, compat_ptr(arg));
1141 		break;
1142 
1143 	case MGSL_IOCGPARAMS32:
1144 		rc = get_params32(info, compat_ptr(arg));
1145 		break;
1146 
1147 	case MGSL_IOCGPARAMS:
1148 	case MGSL_IOCSPARAMS:
1149 	case MGSL_IOCGTXIDLE:
1150 	case MGSL_IOCGSTATS:
1151 	case MGSL_IOCWAITEVENT:
1152 	case MGSL_IOCGIF:
1153 	case MGSL_IOCSGPIO:
1154 	case MGSL_IOCGGPIO:
1155 	case MGSL_IOCWAITGPIO:
1156 	case MGSL_IOCGXSYNC:
1157 	case MGSL_IOCGXCTRL:
1158 		rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1159 		break;
1160 	default:
1161 		rc = ioctl(tty, cmd, arg);
1162 	}
1163 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1164 	return rc;
1165 }
1166 #else
1167 #define slgt_compat_ioctl NULL
1168 #endif /* ifdef CONFIG_COMPAT */
1169 
1170 /*
1171  * proc fs support
1172  */
1173 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1174 {
1175 	char stat_buf[30];
1176 	unsigned long flags;
1177 
1178 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1179 		      info->device_name, info->phys_reg_addr,
1180 		      info->irq_level, info->max_frame_size);
1181 
1182 	/* output current serial signal states */
1183 	spin_lock_irqsave(&info->lock,flags);
1184 	get_gtsignals(info);
1185 	spin_unlock_irqrestore(&info->lock,flags);
1186 
1187 	stat_buf[0] = 0;
1188 	stat_buf[1] = 0;
1189 	if (info->signals & SerialSignal_RTS)
1190 		strcat(stat_buf, "|RTS");
1191 	if (info->signals & SerialSignal_CTS)
1192 		strcat(stat_buf, "|CTS");
1193 	if (info->signals & SerialSignal_DTR)
1194 		strcat(stat_buf, "|DTR");
1195 	if (info->signals & SerialSignal_DSR)
1196 		strcat(stat_buf, "|DSR");
1197 	if (info->signals & SerialSignal_DCD)
1198 		strcat(stat_buf, "|CD");
1199 	if (info->signals & SerialSignal_RI)
1200 		strcat(stat_buf, "|RI");
1201 
1202 	if (info->params.mode != MGSL_MODE_ASYNC) {
1203 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1204 			       info->icount.txok, info->icount.rxok);
1205 		if (info->icount.txunder)
1206 			seq_printf(m, " txunder:%d", info->icount.txunder);
1207 		if (info->icount.txabort)
1208 			seq_printf(m, " txabort:%d", info->icount.txabort);
1209 		if (info->icount.rxshort)
1210 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1211 		if (info->icount.rxlong)
1212 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1213 		if (info->icount.rxover)
1214 			seq_printf(m, " rxover:%d", info->icount.rxover);
1215 		if (info->icount.rxcrc)
1216 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1217 	} else {
1218 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1219 			       info->icount.tx, info->icount.rx);
1220 		if (info->icount.frame)
1221 			seq_printf(m, " fe:%d", info->icount.frame);
1222 		if (info->icount.parity)
1223 			seq_printf(m, " pe:%d", info->icount.parity);
1224 		if (info->icount.brk)
1225 			seq_printf(m, " brk:%d", info->icount.brk);
1226 		if (info->icount.overrun)
1227 			seq_printf(m, " oe:%d", info->icount.overrun);
1228 	}
1229 
1230 	/* Append serial signal status to end */
1231 	seq_printf(m, " %s\n", stat_buf+1);
1232 
1233 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1234 		       info->tx_active,info->bh_requested,info->bh_running,
1235 		       info->pending_bh);
1236 }
1237 
1238 /* Called to print information about devices
1239  */
1240 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1241 {
1242 	struct slgt_info *info;
1243 
1244 	seq_puts(m, "synclink_gt driver\n");
1245 
1246 	info = slgt_device_list;
1247 	while( info ) {
1248 		line_info(m, info);
1249 		info = info->next_device;
1250 	}
1251 	return 0;
1252 }
1253 
1254 /*
1255  * return count of bytes in transmit buffer
1256  */
1257 static unsigned int chars_in_buffer(struct tty_struct *tty)
1258 {
1259 	struct slgt_info *info = tty->driver_data;
1260 	unsigned int count;
1261 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1262 		return 0;
1263 	count = tbuf_bytes(info);
1264 	DBGINFO(("%s chars_in_buffer()=%u\n", info->device_name, count));
1265 	return count;
1266 }
1267 
1268 /*
1269  * signal remote device to throttle send data (our receive data)
1270  */
1271 static void throttle(struct tty_struct * tty)
1272 {
1273 	struct slgt_info *info = tty->driver_data;
1274 	unsigned long flags;
1275 
1276 	if (sanity_check(info, tty->name, "throttle"))
1277 		return;
1278 	DBGINFO(("%s throttle\n", info->device_name));
1279 	if (I_IXOFF(tty))
1280 		send_xchar(tty, STOP_CHAR(tty));
1281 	if (C_CRTSCTS(tty)) {
1282 		spin_lock_irqsave(&info->lock,flags);
1283 		info->signals &= ~SerialSignal_RTS;
1284 		set_gtsignals(info);
1285 		spin_unlock_irqrestore(&info->lock,flags);
1286 	}
1287 }
1288 
1289 /*
1290  * signal remote device to stop throttling send data (our receive data)
1291  */
1292 static void unthrottle(struct tty_struct * tty)
1293 {
1294 	struct slgt_info *info = tty->driver_data;
1295 	unsigned long flags;
1296 
1297 	if (sanity_check(info, tty->name, "unthrottle"))
1298 		return;
1299 	DBGINFO(("%s unthrottle\n", info->device_name));
1300 	if (I_IXOFF(tty)) {
1301 		if (info->x_char)
1302 			info->x_char = 0;
1303 		else
1304 			send_xchar(tty, START_CHAR(tty));
1305 	}
1306 	if (C_CRTSCTS(tty)) {
1307 		spin_lock_irqsave(&info->lock,flags);
1308 		info->signals |= SerialSignal_RTS;
1309 		set_gtsignals(info);
1310 		spin_unlock_irqrestore(&info->lock,flags);
1311 	}
1312 }
1313 
1314 /*
1315  * set or clear transmit break condition
1316  * break_state	-1=set break condition, 0=clear
1317  */
1318 static int set_break(struct tty_struct *tty, int break_state)
1319 {
1320 	struct slgt_info *info = tty->driver_data;
1321 	unsigned short value;
1322 	unsigned long flags;
1323 
1324 	if (sanity_check(info, tty->name, "set_break"))
1325 		return -EINVAL;
1326 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1327 
1328 	spin_lock_irqsave(&info->lock,flags);
1329 	value = rd_reg16(info, TCR);
1330  	if (break_state == -1)
1331 		value |= BIT6;
1332 	else
1333 		value &= ~BIT6;
1334 	wr_reg16(info, TCR, value);
1335 	spin_unlock_irqrestore(&info->lock,flags);
1336 	return 0;
1337 }
1338 
1339 #if SYNCLINK_GENERIC_HDLC
1340 
1341 /**
1342  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1343  * @dev:      pointer to network device structure
1344  * @encoding: serial encoding setting
1345  * @parity:   FCS setting
1346  *
1347  * Set encoding and frame check sequence (FCS) options.
1348  *
1349  * Return: 0 if success, otherwise error code
1350  */
1351 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1352 			  unsigned short parity)
1353 {
1354 	struct slgt_info *info = dev_to_port(dev);
1355 	unsigned char  new_encoding;
1356 	unsigned short new_crctype;
1357 
1358 	/* return error if TTY interface open */
1359 	if (info->port.count)
1360 		return -EBUSY;
1361 
1362 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1363 
1364 	switch (encoding)
1365 	{
1366 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1367 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1368 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1369 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1370 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1371 	default: return -EINVAL;
1372 	}
1373 
1374 	switch (parity)
1375 	{
1376 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1377 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1378 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1379 	default: return -EINVAL;
1380 	}
1381 
1382 	info->params.encoding = new_encoding;
1383 	info->params.crc_type = new_crctype;
1384 
1385 	/* if network interface up, reprogram hardware */
1386 	if (info->netcount)
1387 		program_hw(info);
1388 
1389 	return 0;
1390 }
1391 
1392 /**
1393  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1394  * @skb: socket buffer containing HDLC frame
1395  * @dev: pointer to network device structure
1396  */
1397 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1398 				      struct net_device *dev)
1399 {
1400 	struct slgt_info *info = dev_to_port(dev);
1401 	unsigned long flags;
1402 
1403 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1404 
1405 	if (!skb->len)
1406 		return NETDEV_TX_OK;
1407 
1408 	/* stop sending until this frame completes */
1409 	netif_stop_queue(dev);
1410 
1411 	/* update network statistics */
1412 	dev->stats.tx_packets++;
1413 	dev->stats.tx_bytes += skb->len;
1414 
1415 	/* save start time for transmit timeout detection */
1416 	netif_trans_update(dev);
1417 
1418 	spin_lock_irqsave(&info->lock, flags);
1419 	tx_load(info, skb->data, skb->len);
1420 	spin_unlock_irqrestore(&info->lock, flags);
1421 
1422 	/* done with socket buffer, so free it */
1423 	dev_kfree_skb(skb);
1424 
1425 	return NETDEV_TX_OK;
1426 }
1427 
1428 /**
1429  * hdlcdev_open - called by network layer when interface enabled
1430  * @dev: pointer to network device structure
1431  *
1432  * Claim resources and initialize hardware.
1433  *
1434  * Return: 0 if success, otherwise error code
1435  */
1436 static int hdlcdev_open(struct net_device *dev)
1437 {
1438 	struct slgt_info *info = dev_to_port(dev);
1439 	int rc;
1440 	unsigned long flags;
1441 
1442 	if (!try_module_get(THIS_MODULE))
1443 		return -EBUSY;
1444 
1445 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1446 
1447 	/* generic HDLC layer open processing */
1448 	rc = hdlc_open(dev);
1449 	if (rc)
1450 		return rc;
1451 
1452 	/* arbitrate between network and tty opens */
1453 	spin_lock_irqsave(&info->netlock, flags);
1454 	if (info->port.count != 0 || info->netcount != 0) {
1455 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1456 		spin_unlock_irqrestore(&info->netlock, flags);
1457 		return -EBUSY;
1458 	}
1459 	info->netcount=1;
1460 	spin_unlock_irqrestore(&info->netlock, flags);
1461 
1462 	/* claim resources and init adapter */
1463 	if ((rc = startup(info)) != 0) {
1464 		spin_lock_irqsave(&info->netlock, flags);
1465 		info->netcount=0;
1466 		spin_unlock_irqrestore(&info->netlock, flags);
1467 		return rc;
1468 	}
1469 
1470 	/* assert RTS and DTR, apply hardware settings */
1471 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1472 	program_hw(info);
1473 
1474 	/* enable network layer transmit */
1475 	netif_trans_update(dev);
1476 	netif_start_queue(dev);
1477 
1478 	/* inform generic HDLC layer of current DCD status */
1479 	spin_lock_irqsave(&info->lock, flags);
1480 	get_gtsignals(info);
1481 	spin_unlock_irqrestore(&info->lock, flags);
1482 	if (info->signals & SerialSignal_DCD)
1483 		netif_carrier_on(dev);
1484 	else
1485 		netif_carrier_off(dev);
1486 	return 0;
1487 }
1488 
1489 /**
1490  * hdlcdev_close - called by network layer when interface is disabled
1491  * @dev:  pointer to network device structure
1492  *
1493  * Shutdown hardware and release resources.
1494  *
1495  * Return: 0 if success, otherwise error code
1496  */
1497 static int hdlcdev_close(struct net_device *dev)
1498 {
1499 	struct slgt_info *info = dev_to_port(dev);
1500 	unsigned long flags;
1501 
1502 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1503 
1504 	netif_stop_queue(dev);
1505 
1506 	/* shutdown adapter and release resources */
1507 	shutdown(info);
1508 
1509 	hdlc_close(dev);
1510 
1511 	spin_lock_irqsave(&info->netlock, flags);
1512 	info->netcount=0;
1513 	spin_unlock_irqrestore(&info->netlock, flags);
1514 
1515 	module_put(THIS_MODULE);
1516 	return 0;
1517 }
1518 
1519 /**
1520  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1521  * @dev: pointer to network device structure
1522  * @ifr: pointer to network interface request structure
1523  * @cmd: IOCTL command code
1524  *
1525  * Return: 0 if success, otherwise error code
1526  */
1527 static int hdlcdev_ioctl(struct net_device *dev, struct if_settings *ifs)
1528 {
1529 	const size_t size = sizeof(sync_serial_settings);
1530 	sync_serial_settings new_line;
1531 	sync_serial_settings __user *line = ifs->ifs_ifsu.sync;
1532 	struct slgt_info *info = dev_to_port(dev);
1533 	unsigned int flags;
1534 
1535 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1536 
1537 	/* return error if TTY interface open */
1538 	if (info->port.count)
1539 		return -EBUSY;
1540 
1541 	memset(&new_line, 0, sizeof(new_line));
1542 
1543 	switch (ifs->type) {
1544 	case IF_GET_IFACE: /* return current sync_serial_settings */
1545 
1546 		ifs->type = IF_IFACE_SYNC_SERIAL;
1547 		if (ifs->size < size) {
1548 			ifs->size = size; /* data size wanted */
1549 			return -ENOBUFS;
1550 		}
1551 
1552 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1553 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1554 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1555 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1556 
1557 		switch (flags){
1558 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1559 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1560 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1561 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1562 		default: new_line.clock_type = CLOCK_DEFAULT;
1563 		}
1564 
1565 		new_line.clock_rate = info->params.clock_speed;
1566 		new_line.loopback   = info->params.loopback ? 1:0;
1567 
1568 		if (copy_to_user(line, &new_line, size))
1569 			return -EFAULT;
1570 		return 0;
1571 
1572 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1573 
1574 		if(!capable(CAP_NET_ADMIN))
1575 			return -EPERM;
1576 		if (copy_from_user(&new_line, line, size))
1577 			return -EFAULT;
1578 
1579 		switch (new_line.clock_type)
1580 		{
1581 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1582 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1583 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1584 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1585 		case CLOCK_DEFAULT:  flags = info->params.flags &
1586 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1587 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1588 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1589 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1590 		default: return -EINVAL;
1591 		}
1592 
1593 		if (new_line.loopback != 0 && new_line.loopback != 1)
1594 			return -EINVAL;
1595 
1596 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1597 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1598 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1599 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1600 		info->params.flags |= flags;
1601 
1602 		info->params.loopback = new_line.loopback;
1603 
1604 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1605 			info->params.clock_speed = new_line.clock_rate;
1606 		else
1607 			info->params.clock_speed = 0;
1608 
1609 		/* if network interface up, reprogram hardware */
1610 		if (info->netcount)
1611 			program_hw(info);
1612 		return 0;
1613 
1614 	default:
1615 		return hdlc_ioctl(dev, ifs);
1616 	}
1617 }
1618 
1619 /**
1620  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1621  * @dev: pointer to network device structure
1622  * @txqueue: unused
1623  */
1624 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1625 {
1626 	struct slgt_info *info = dev_to_port(dev);
1627 	unsigned long flags;
1628 
1629 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1630 
1631 	dev->stats.tx_errors++;
1632 	dev->stats.tx_aborted_errors++;
1633 
1634 	spin_lock_irqsave(&info->lock,flags);
1635 	tx_stop(info);
1636 	spin_unlock_irqrestore(&info->lock,flags);
1637 
1638 	netif_wake_queue(dev);
1639 }
1640 
1641 /**
1642  * hdlcdev_tx_done - called by device driver when transmit completes
1643  * @info: pointer to device instance information
1644  *
1645  * Reenable network layer transmit if stopped.
1646  */
1647 static void hdlcdev_tx_done(struct slgt_info *info)
1648 {
1649 	if (netif_queue_stopped(info->netdev))
1650 		netif_wake_queue(info->netdev);
1651 }
1652 
1653 /**
1654  * hdlcdev_rx - called by device driver when frame received
1655  * @info: pointer to device instance information
1656  * @buf:  pointer to buffer contianing frame data
1657  * @size: count of data bytes in buf
1658  *
1659  * Pass frame to network layer.
1660  */
1661 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1662 {
1663 	struct sk_buff *skb = dev_alloc_skb(size);
1664 	struct net_device *dev = info->netdev;
1665 
1666 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1667 
1668 	if (skb == NULL) {
1669 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1670 		dev->stats.rx_dropped++;
1671 		return;
1672 	}
1673 
1674 	skb_put_data(skb, buf, size);
1675 
1676 	skb->protocol = hdlc_type_trans(skb, dev);
1677 
1678 	dev->stats.rx_packets++;
1679 	dev->stats.rx_bytes += size;
1680 
1681 	netif_rx(skb);
1682 }
1683 
1684 static const struct net_device_ops hdlcdev_ops = {
1685 	.ndo_open       = hdlcdev_open,
1686 	.ndo_stop       = hdlcdev_close,
1687 	.ndo_start_xmit = hdlc_start_xmit,
1688 	.ndo_siocwandev = hdlcdev_ioctl,
1689 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1690 };
1691 
1692 /**
1693  * hdlcdev_init - called by device driver when adding device instance
1694  * @info: pointer to device instance information
1695  *
1696  * Do generic HDLC initialization.
1697  *
1698  * Return: 0 if success, otherwise error code
1699  */
1700 static int hdlcdev_init(struct slgt_info *info)
1701 {
1702 	int rc;
1703 	struct net_device *dev;
1704 	hdlc_device *hdlc;
1705 
1706 	/* allocate and initialize network and HDLC layer objects */
1707 
1708 	dev = alloc_hdlcdev(info);
1709 	if (!dev) {
1710 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1711 		return -ENOMEM;
1712 	}
1713 
1714 	/* for network layer reporting purposes only */
1715 	dev->mem_start = info->phys_reg_addr;
1716 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1717 	dev->irq       = info->irq_level;
1718 
1719 	/* network layer callbacks and settings */
1720 	dev->netdev_ops	    = &hdlcdev_ops;
1721 	dev->watchdog_timeo = 10 * HZ;
1722 	dev->tx_queue_len   = 50;
1723 
1724 	/* generic HDLC layer callbacks and settings */
1725 	hdlc         = dev_to_hdlc(dev);
1726 	hdlc->attach = hdlcdev_attach;
1727 	hdlc->xmit   = hdlcdev_xmit;
1728 
1729 	/* register objects with HDLC layer */
1730 	rc = register_hdlc_device(dev);
1731 	if (rc) {
1732 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1733 		free_netdev(dev);
1734 		return rc;
1735 	}
1736 
1737 	info->netdev = dev;
1738 	return 0;
1739 }
1740 
1741 /**
1742  * hdlcdev_exit - called by device driver when removing device instance
1743  * @info: pointer to device instance information
1744  *
1745  * Do generic HDLC cleanup.
1746  */
1747 static void hdlcdev_exit(struct slgt_info *info)
1748 {
1749 	if (!info->netdev)
1750 		return;
1751 	unregister_hdlc_device(info->netdev);
1752 	free_netdev(info->netdev);
1753 	info->netdev = NULL;
1754 }
1755 
1756 #endif /* ifdef CONFIG_HDLC */
1757 
1758 /*
1759  * get async data from rx DMA buffers
1760  */
1761 static void rx_async(struct slgt_info *info)
1762 {
1763  	struct mgsl_icount *icount = &info->icount;
1764 	unsigned int start, end;
1765 	unsigned char *p;
1766 	unsigned char status;
1767 	struct slgt_desc *bufs = info->rbufs;
1768 	int i, count;
1769 	int chars = 0;
1770 	int stat;
1771 	unsigned char ch;
1772 
1773 	start = end = info->rbuf_current;
1774 
1775 	while(desc_complete(bufs[end])) {
1776 		count = desc_count(bufs[end]) - info->rbuf_index;
1777 		p     = bufs[end].buf + info->rbuf_index;
1778 
1779 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1780 		DBGDATA(info, p, count, "rx");
1781 
1782 		for(i=0 ; i < count; i+=2, p+=2) {
1783 			ch = *p;
1784 			icount->rx++;
1785 
1786 			stat = 0;
1787 
1788 			status = *(p + 1) & (BIT1 + BIT0);
1789 			if (status) {
1790 				if (status & BIT1)
1791 					icount->parity++;
1792 				else if (status & BIT0)
1793 					icount->frame++;
1794 				/* discard char if tty control flags say so */
1795 				if (status & info->ignore_status_mask)
1796 					continue;
1797 				if (status & BIT1)
1798 					stat = TTY_PARITY;
1799 				else if (status & BIT0)
1800 					stat = TTY_FRAME;
1801 			}
1802 			tty_insert_flip_char(&info->port, ch, stat);
1803 			chars++;
1804 		}
1805 
1806 		if (i < count) {
1807 			/* receive buffer not completed */
1808 			info->rbuf_index += i;
1809 			mod_timer(&info->rx_timer, jiffies + 1);
1810 			break;
1811 		}
1812 
1813 		info->rbuf_index = 0;
1814 		free_rbufs(info, end, end);
1815 
1816 		if (++end == info->rbuf_count)
1817 			end = 0;
1818 
1819 		/* if entire list searched then no frame available */
1820 		if (end == start)
1821 			break;
1822 	}
1823 
1824 	if (chars)
1825 		tty_flip_buffer_push(&info->port);
1826 }
1827 
1828 /*
1829  * return next bottom half action to perform
1830  */
1831 static int bh_action(struct slgt_info *info)
1832 {
1833 	unsigned long flags;
1834 	int rc;
1835 
1836 	spin_lock_irqsave(&info->lock,flags);
1837 
1838 	if (info->pending_bh & BH_RECEIVE) {
1839 		info->pending_bh &= ~BH_RECEIVE;
1840 		rc = BH_RECEIVE;
1841 	} else if (info->pending_bh & BH_TRANSMIT) {
1842 		info->pending_bh &= ~BH_TRANSMIT;
1843 		rc = BH_TRANSMIT;
1844 	} else if (info->pending_bh & BH_STATUS) {
1845 		info->pending_bh &= ~BH_STATUS;
1846 		rc = BH_STATUS;
1847 	} else {
1848 		/* Mark BH routine as complete */
1849 		info->bh_running = false;
1850 		info->bh_requested = false;
1851 		rc = 0;
1852 	}
1853 
1854 	spin_unlock_irqrestore(&info->lock,flags);
1855 
1856 	return rc;
1857 }
1858 
1859 /*
1860  * perform bottom half processing
1861  */
1862 static void bh_handler(struct work_struct *work)
1863 {
1864 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1865 	int action;
1866 
1867 	info->bh_running = true;
1868 
1869 	while((action = bh_action(info))) {
1870 		switch (action) {
1871 		case BH_RECEIVE:
1872 			DBGBH(("%s bh receive\n", info->device_name));
1873 			switch(info->params.mode) {
1874 			case MGSL_MODE_ASYNC:
1875 				rx_async(info);
1876 				break;
1877 			case MGSL_MODE_HDLC:
1878 				while(rx_get_frame(info));
1879 				break;
1880 			case MGSL_MODE_RAW:
1881 			case MGSL_MODE_MONOSYNC:
1882 			case MGSL_MODE_BISYNC:
1883 			case MGSL_MODE_XSYNC:
1884 				while(rx_get_buf(info));
1885 				break;
1886 			}
1887 			/* restart receiver if rx DMA buffers exhausted */
1888 			if (info->rx_restart)
1889 				rx_start(info);
1890 			break;
1891 		case BH_TRANSMIT:
1892 			bh_transmit(info);
1893 			break;
1894 		case BH_STATUS:
1895 			DBGBH(("%s bh status\n", info->device_name));
1896 			info->ri_chkcount = 0;
1897 			info->dsr_chkcount = 0;
1898 			info->dcd_chkcount = 0;
1899 			info->cts_chkcount = 0;
1900 			break;
1901 		default:
1902 			DBGBH(("%s unknown action\n", info->device_name));
1903 			break;
1904 		}
1905 	}
1906 	DBGBH(("%s bh_handler exit\n", info->device_name));
1907 }
1908 
1909 static void bh_transmit(struct slgt_info *info)
1910 {
1911 	struct tty_struct *tty = info->port.tty;
1912 
1913 	DBGBH(("%s bh_transmit\n", info->device_name));
1914 	if (tty)
1915 		tty_wakeup(tty);
1916 }
1917 
1918 static void dsr_change(struct slgt_info *info, unsigned short status)
1919 {
1920 	if (status & BIT3) {
1921 		info->signals |= SerialSignal_DSR;
1922 		info->input_signal_events.dsr_up++;
1923 	} else {
1924 		info->signals &= ~SerialSignal_DSR;
1925 		info->input_signal_events.dsr_down++;
1926 	}
1927 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1928 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1929 		slgt_irq_off(info, IRQ_DSR);
1930 		return;
1931 	}
1932 	info->icount.dsr++;
1933 	wake_up_interruptible(&info->status_event_wait_q);
1934 	wake_up_interruptible(&info->event_wait_q);
1935 	info->pending_bh |= BH_STATUS;
1936 }
1937 
1938 static void cts_change(struct slgt_info *info, unsigned short status)
1939 {
1940 	if (status & BIT2) {
1941 		info->signals |= SerialSignal_CTS;
1942 		info->input_signal_events.cts_up++;
1943 	} else {
1944 		info->signals &= ~SerialSignal_CTS;
1945 		info->input_signal_events.cts_down++;
1946 	}
1947 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1948 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1949 		slgt_irq_off(info, IRQ_CTS);
1950 		return;
1951 	}
1952 	info->icount.cts++;
1953 	wake_up_interruptible(&info->status_event_wait_q);
1954 	wake_up_interruptible(&info->event_wait_q);
1955 	info->pending_bh |= BH_STATUS;
1956 
1957 	if (tty_port_cts_enabled(&info->port)) {
1958 		if (info->port.tty) {
1959 			if (info->port.tty->hw_stopped) {
1960 				if (info->signals & SerialSignal_CTS) {
1961 		 			info->port.tty->hw_stopped = 0;
1962 					info->pending_bh |= BH_TRANSMIT;
1963 					return;
1964 				}
1965 			} else {
1966 				if (!(info->signals & SerialSignal_CTS))
1967 		 			info->port.tty->hw_stopped = 1;
1968 			}
1969 		}
1970 	}
1971 }
1972 
1973 static void dcd_change(struct slgt_info *info, unsigned short status)
1974 {
1975 	if (status & BIT1) {
1976 		info->signals |= SerialSignal_DCD;
1977 		info->input_signal_events.dcd_up++;
1978 	} else {
1979 		info->signals &= ~SerialSignal_DCD;
1980 		info->input_signal_events.dcd_down++;
1981 	}
1982 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1983 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1984 		slgt_irq_off(info, IRQ_DCD);
1985 		return;
1986 	}
1987 	info->icount.dcd++;
1988 #if SYNCLINK_GENERIC_HDLC
1989 	if (info->netcount) {
1990 		if (info->signals & SerialSignal_DCD)
1991 			netif_carrier_on(info->netdev);
1992 		else
1993 			netif_carrier_off(info->netdev);
1994 	}
1995 #endif
1996 	wake_up_interruptible(&info->status_event_wait_q);
1997 	wake_up_interruptible(&info->event_wait_q);
1998 	info->pending_bh |= BH_STATUS;
1999 
2000 	if (tty_port_check_carrier(&info->port)) {
2001 		if (info->signals & SerialSignal_DCD)
2002 			wake_up_interruptible(&info->port.open_wait);
2003 		else {
2004 			if (info->port.tty)
2005 				tty_hangup(info->port.tty);
2006 		}
2007 	}
2008 }
2009 
2010 static void ri_change(struct slgt_info *info, unsigned short status)
2011 {
2012 	if (status & BIT0) {
2013 		info->signals |= SerialSignal_RI;
2014 		info->input_signal_events.ri_up++;
2015 	} else {
2016 		info->signals &= ~SerialSignal_RI;
2017 		info->input_signal_events.ri_down++;
2018 	}
2019 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2020 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2021 		slgt_irq_off(info, IRQ_RI);
2022 		return;
2023 	}
2024 	info->icount.rng++;
2025 	wake_up_interruptible(&info->status_event_wait_q);
2026 	wake_up_interruptible(&info->event_wait_q);
2027 	info->pending_bh |= BH_STATUS;
2028 }
2029 
2030 static void isr_rxdata(struct slgt_info *info)
2031 {
2032 	unsigned int count = info->rbuf_fill_count;
2033 	unsigned int i = info->rbuf_fill_index;
2034 	unsigned short reg;
2035 
2036 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2037 		reg = rd_reg16(info, RDR);
2038 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2039 		if (desc_complete(info->rbufs[i])) {
2040 			/* all buffers full */
2041 			rx_stop(info);
2042 			info->rx_restart = true;
2043 			continue;
2044 		}
2045 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2046 		/* async mode saves status byte to buffer for each data byte */
2047 		if (info->params.mode == MGSL_MODE_ASYNC)
2048 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2049 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2050 			/* buffer full or end of frame */
2051 			set_desc_count(info->rbufs[i], count);
2052 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2053 			info->rbuf_fill_count = count = 0;
2054 			if (++i == info->rbuf_count)
2055 				i = 0;
2056 			info->pending_bh |= BH_RECEIVE;
2057 		}
2058 	}
2059 
2060 	info->rbuf_fill_index = i;
2061 	info->rbuf_fill_count = count;
2062 }
2063 
2064 static void isr_serial(struct slgt_info *info)
2065 {
2066 	unsigned short status = rd_reg16(info, SSR);
2067 
2068 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2069 
2070 	wr_reg16(info, SSR, status); /* clear pending */
2071 
2072 	info->irq_occurred = true;
2073 
2074 	if (info->params.mode == MGSL_MODE_ASYNC) {
2075 		if (status & IRQ_TXIDLE) {
2076 			if (info->tx_active)
2077 				isr_txeom(info, status);
2078 		}
2079 		if (info->rx_pio && (status & IRQ_RXDATA))
2080 			isr_rxdata(info);
2081 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2082 			info->icount.brk++;
2083 			/* process break detection if tty control allows */
2084 			if (info->port.tty) {
2085 				if (!(status & info->ignore_status_mask)) {
2086 					if (info->read_status_mask & MASK_BREAK) {
2087 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2088 						if (info->port.flags & ASYNC_SAK)
2089 							do_SAK(info->port.tty);
2090 					}
2091 				}
2092 			}
2093 		}
2094 	} else {
2095 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2096 			isr_txeom(info, status);
2097 		if (info->rx_pio && (status & IRQ_RXDATA))
2098 			isr_rxdata(info);
2099 		if (status & IRQ_RXIDLE) {
2100 			if (status & RXIDLE)
2101 				info->icount.rxidle++;
2102 			else
2103 				info->icount.exithunt++;
2104 			wake_up_interruptible(&info->event_wait_q);
2105 		}
2106 
2107 		if (status & IRQ_RXOVER)
2108 			rx_start(info);
2109 	}
2110 
2111 	if (status & IRQ_DSR)
2112 		dsr_change(info, status);
2113 	if (status & IRQ_CTS)
2114 		cts_change(info, status);
2115 	if (status & IRQ_DCD)
2116 		dcd_change(info, status);
2117 	if (status & IRQ_RI)
2118 		ri_change(info, status);
2119 }
2120 
2121 static void isr_rdma(struct slgt_info *info)
2122 {
2123 	unsigned int status = rd_reg32(info, RDCSR);
2124 
2125 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2126 
2127 	/* RDCSR (rx DMA control/status)
2128 	 *
2129 	 * 31..07  reserved
2130 	 * 06      save status byte to DMA buffer
2131 	 * 05      error
2132 	 * 04      eol (end of list)
2133 	 * 03      eob (end of buffer)
2134 	 * 02      IRQ enable
2135 	 * 01      reset
2136 	 * 00      enable
2137 	 */
2138 	wr_reg32(info, RDCSR, status);	/* clear pending */
2139 
2140 	if (status & (BIT5 + BIT4)) {
2141 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2142 		info->rx_restart = true;
2143 	}
2144 	info->pending_bh |= BH_RECEIVE;
2145 }
2146 
2147 static void isr_tdma(struct slgt_info *info)
2148 {
2149 	unsigned int status = rd_reg32(info, TDCSR);
2150 
2151 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2152 
2153 	/* TDCSR (tx DMA control/status)
2154 	 *
2155 	 * 31..06  reserved
2156 	 * 05      error
2157 	 * 04      eol (end of list)
2158 	 * 03      eob (end of buffer)
2159 	 * 02      IRQ enable
2160 	 * 01      reset
2161 	 * 00      enable
2162 	 */
2163 	wr_reg32(info, TDCSR, status);	/* clear pending */
2164 
2165 	if (status & (BIT5 + BIT4 + BIT3)) {
2166 		// another transmit buffer has completed
2167 		// run bottom half to get more send data from user
2168 		info->pending_bh |= BH_TRANSMIT;
2169 	}
2170 }
2171 
2172 /*
2173  * return true if there are unsent tx DMA buffers, otherwise false
2174  *
2175  * if there are unsent buffers then info->tbuf_start
2176  * is set to index of first unsent buffer
2177  */
2178 static bool unsent_tbufs(struct slgt_info *info)
2179 {
2180 	unsigned int i = info->tbuf_current;
2181 	bool rc = false;
2182 
2183 	/*
2184 	 * search backwards from last loaded buffer (precedes tbuf_current)
2185 	 * for first unsent buffer (desc_count > 0)
2186 	 */
2187 
2188 	do {
2189 		if (i)
2190 			i--;
2191 		else
2192 			i = info->tbuf_count - 1;
2193 		if (!desc_count(info->tbufs[i]))
2194 			break;
2195 		info->tbuf_start = i;
2196 		rc = true;
2197 	} while (i != info->tbuf_current);
2198 
2199 	return rc;
2200 }
2201 
2202 static void isr_txeom(struct slgt_info *info, unsigned short status)
2203 {
2204 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2205 
2206 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2207 	tdma_reset(info);
2208 	if (status & IRQ_TXUNDER) {
2209 		unsigned short val = rd_reg16(info, TCR);
2210 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2211 		wr_reg16(info, TCR, val); /* clear reset bit */
2212 	}
2213 
2214 	if (info->tx_active) {
2215 		if (info->params.mode != MGSL_MODE_ASYNC) {
2216 			if (status & IRQ_TXUNDER)
2217 				info->icount.txunder++;
2218 			else if (status & IRQ_TXIDLE)
2219 				info->icount.txok++;
2220 		}
2221 
2222 		if (unsent_tbufs(info)) {
2223 			tx_start(info);
2224 			update_tx_timer(info);
2225 			return;
2226 		}
2227 		info->tx_active = false;
2228 
2229 		del_timer(&info->tx_timer);
2230 
2231 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2232 			info->signals &= ~SerialSignal_RTS;
2233 			info->drop_rts_on_tx_done = false;
2234 			set_gtsignals(info);
2235 		}
2236 
2237 #if SYNCLINK_GENERIC_HDLC
2238 		if (info->netcount)
2239 			hdlcdev_tx_done(info);
2240 		else
2241 #endif
2242 		{
2243 			if (info->port.tty && (info->port.tty->flow.stopped || info->port.tty->hw_stopped)) {
2244 				tx_stop(info);
2245 				return;
2246 			}
2247 			info->pending_bh |= BH_TRANSMIT;
2248 		}
2249 	}
2250 }
2251 
2252 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2253 {
2254 	struct cond_wait *w, *prev;
2255 
2256 	/* wake processes waiting for specific transitions */
2257 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2258 		if (w->data & changed) {
2259 			w->data = state;
2260 			wake_up_interruptible(&w->q);
2261 			if (prev != NULL)
2262 				prev->next = w->next;
2263 			else
2264 				info->gpio_wait_q = w->next;
2265 		} else
2266 			prev = w;
2267 	}
2268 }
2269 
2270 /* interrupt service routine
2271  *
2272  * 	irq	interrupt number
2273  * 	dev_id	device ID supplied during interrupt registration
2274  */
2275 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2276 {
2277 	struct slgt_info *info = dev_id;
2278 	unsigned int gsr;
2279 	unsigned int i;
2280 
2281 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2282 
2283 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2284 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2285 		info->irq_occurred = true;
2286 		for(i=0; i < info->port_count ; i++) {
2287 			if (info->port_array[i] == NULL)
2288 				continue;
2289 			spin_lock(&info->port_array[i]->lock);
2290 			if (gsr & (BIT8 << i))
2291 				isr_serial(info->port_array[i]);
2292 			if (gsr & (BIT16 << (i*2)))
2293 				isr_rdma(info->port_array[i]);
2294 			if (gsr & (BIT17 << (i*2)))
2295 				isr_tdma(info->port_array[i]);
2296 			spin_unlock(&info->port_array[i]->lock);
2297 		}
2298 	}
2299 
2300 	if (info->gpio_present) {
2301 		unsigned int state;
2302 		unsigned int changed;
2303 		spin_lock(&info->lock);
2304 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2305 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2306 			/* read latched state of GPIO signals */
2307 			state = rd_reg32(info, IOVR);
2308 			/* clear pending GPIO interrupt bits */
2309 			wr_reg32(info, IOSR, changed);
2310 			for (i=0 ; i < info->port_count ; i++) {
2311 				if (info->port_array[i] != NULL)
2312 					isr_gpio(info->port_array[i], changed, state);
2313 			}
2314 		}
2315 		spin_unlock(&info->lock);
2316 	}
2317 
2318 	for(i=0; i < info->port_count ; i++) {
2319 		struct slgt_info *port = info->port_array[i];
2320 		if (port == NULL)
2321 			continue;
2322 		spin_lock(&port->lock);
2323 		if ((port->port.count || port->netcount) &&
2324 		    port->pending_bh && !port->bh_running &&
2325 		    !port->bh_requested) {
2326 			DBGISR(("%s bh queued\n", port->device_name));
2327 			schedule_work(&port->task);
2328 			port->bh_requested = true;
2329 		}
2330 		spin_unlock(&port->lock);
2331 	}
2332 
2333 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2334 	return IRQ_HANDLED;
2335 }
2336 
2337 static int startup(struct slgt_info *info)
2338 {
2339 	DBGINFO(("%s startup\n", info->device_name));
2340 
2341 	if (tty_port_initialized(&info->port))
2342 		return 0;
2343 
2344 	if (!info->tx_buf) {
2345 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2346 		if (!info->tx_buf) {
2347 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2348 			return -ENOMEM;
2349 		}
2350 	}
2351 
2352 	info->pending_bh = 0;
2353 
2354 	memset(&info->icount, 0, sizeof(info->icount));
2355 
2356 	/* program hardware for current parameters */
2357 	change_params(info);
2358 
2359 	if (info->port.tty)
2360 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2361 
2362 	tty_port_set_initialized(&info->port, 1);
2363 
2364 	return 0;
2365 }
2366 
2367 /*
2368  *  called by close() and hangup() to shutdown hardware
2369  */
2370 static void shutdown(struct slgt_info *info)
2371 {
2372 	unsigned long flags;
2373 
2374 	if (!tty_port_initialized(&info->port))
2375 		return;
2376 
2377 	DBGINFO(("%s shutdown\n", info->device_name));
2378 
2379 	/* clear status wait queue because status changes */
2380 	/* can't happen after shutting down the hardware */
2381 	wake_up_interruptible(&info->status_event_wait_q);
2382 	wake_up_interruptible(&info->event_wait_q);
2383 
2384 	del_timer_sync(&info->tx_timer);
2385 	del_timer_sync(&info->rx_timer);
2386 
2387 	kfree(info->tx_buf);
2388 	info->tx_buf = NULL;
2389 
2390 	spin_lock_irqsave(&info->lock,flags);
2391 
2392 	tx_stop(info);
2393 	rx_stop(info);
2394 
2395 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2396 
2397  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2398 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2399 		set_gtsignals(info);
2400 	}
2401 
2402 	flush_cond_wait(&info->gpio_wait_q);
2403 
2404 	spin_unlock_irqrestore(&info->lock,flags);
2405 
2406 	if (info->port.tty)
2407 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2408 
2409 	tty_port_set_initialized(&info->port, 0);
2410 }
2411 
2412 static void program_hw(struct slgt_info *info)
2413 {
2414 	unsigned long flags;
2415 
2416 	spin_lock_irqsave(&info->lock,flags);
2417 
2418 	rx_stop(info);
2419 	tx_stop(info);
2420 
2421 	if (info->params.mode != MGSL_MODE_ASYNC ||
2422 	    info->netcount)
2423 		sync_mode(info);
2424 	else
2425 		async_mode(info);
2426 
2427 	set_gtsignals(info);
2428 
2429 	info->dcd_chkcount = 0;
2430 	info->cts_chkcount = 0;
2431 	info->ri_chkcount = 0;
2432 	info->dsr_chkcount = 0;
2433 
2434 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2435 	get_gtsignals(info);
2436 
2437 	if (info->netcount ||
2438 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2439 		rx_start(info);
2440 
2441 	spin_unlock_irqrestore(&info->lock,flags);
2442 }
2443 
2444 /*
2445  * reconfigure adapter based on new parameters
2446  */
2447 static void change_params(struct slgt_info *info)
2448 {
2449 	unsigned cflag;
2450 	int bits_per_char;
2451 
2452 	if (!info->port.tty)
2453 		return;
2454 	DBGINFO(("%s change_params\n", info->device_name));
2455 
2456 	cflag = info->port.tty->termios.c_cflag;
2457 
2458 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2459 	/* otherwise assert RTS and DTR */
2460  	if (cflag & CBAUD)
2461 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2462 	else
2463 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2464 
2465 	/* byte size and parity */
2466 
2467 	info->params.data_bits = tty_get_char_size(cflag);
2468 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2469 
2470 	if (cflag & PARENB)
2471 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2472 	else
2473 		info->params.parity = ASYNC_PARITY_NONE;
2474 
2475 	/* calculate number of jiffies to transmit a full
2476 	 * FIFO (32 bytes) at specified data rate
2477 	 */
2478 	bits_per_char = info->params.data_bits +
2479 			info->params.stop_bits + 1;
2480 
2481 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2482 
2483 	if (info->params.data_rate) {
2484 		info->timeout = (32*HZ*bits_per_char) /
2485 				info->params.data_rate;
2486 	}
2487 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2488 
2489 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2490 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2491 
2492 	/* process tty input control flags */
2493 
2494 	info->read_status_mask = IRQ_RXOVER;
2495 	if (I_INPCK(info->port.tty))
2496 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2497 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2498 		info->read_status_mask |= MASK_BREAK;
2499 	if (I_IGNPAR(info->port.tty))
2500 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2501 	if (I_IGNBRK(info->port.tty)) {
2502 		info->ignore_status_mask |= MASK_BREAK;
2503 		/* If ignoring parity and break indicators, ignore
2504 		 * overruns too.  (For real raw support).
2505 		 */
2506 		if (I_IGNPAR(info->port.tty))
2507 			info->ignore_status_mask |= MASK_OVERRUN;
2508 	}
2509 
2510 	program_hw(info);
2511 }
2512 
2513 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2514 {
2515 	DBGINFO(("%s get_stats\n",  info->device_name));
2516 	if (!user_icount) {
2517 		memset(&info->icount, 0, sizeof(info->icount));
2518 	} else {
2519 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2520 			return -EFAULT;
2521 	}
2522 	return 0;
2523 }
2524 
2525 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2526 {
2527 	DBGINFO(("%s get_params\n", info->device_name));
2528 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2529 		return -EFAULT;
2530 	return 0;
2531 }
2532 
2533 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2534 {
2535  	unsigned long flags;
2536 	MGSL_PARAMS tmp_params;
2537 
2538 	DBGINFO(("%s set_params\n", info->device_name));
2539 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2540 		return -EFAULT;
2541 
2542 	spin_lock_irqsave(&info->lock, flags);
2543 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2544 		info->base_clock = tmp_params.clock_speed;
2545 	else
2546 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2547 	spin_unlock_irqrestore(&info->lock, flags);
2548 
2549 	program_hw(info);
2550 
2551 	return 0;
2552 }
2553 
2554 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2555 {
2556 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2557 	if (put_user(info->idle_mode, idle_mode))
2558 		return -EFAULT;
2559 	return 0;
2560 }
2561 
2562 static int set_txidle(struct slgt_info *info, int idle_mode)
2563 {
2564  	unsigned long flags;
2565 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2566 	spin_lock_irqsave(&info->lock,flags);
2567 	info->idle_mode = idle_mode;
2568 	if (info->params.mode != MGSL_MODE_ASYNC)
2569 		tx_set_idle(info);
2570 	spin_unlock_irqrestore(&info->lock,flags);
2571 	return 0;
2572 }
2573 
2574 static int tx_enable(struct slgt_info *info, int enable)
2575 {
2576  	unsigned long flags;
2577 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2578 	spin_lock_irqsave(&info->lock,flags);
2579 	if (enable) {
2580 		if (!info->tx_enabled)
2581 			tx_start(info);
2582 	} else {
2583 		if (info->tx_enabled)
2584 			tx_stop(info);
2585 	}
2586 	spin_unlock_irqrestore(&info->lock,flags);
2587 	return 0;
2588 }
2589 
2590 /*
2591  * abort transmit HDLC frame
2592  */
2593 static int tx_abort(struct slgt_info *info)
2594 {
2595  	unsigned long flags;
2596 	DBGINFO(("%s tx_abort\n", info->device_name));
2597 	spin_lock_irqsave(&info->lock,flags);
2598 	tdma_reset(info);
2599 	spin_unlock_irqrestore(&info->lock,flags);
2600 	return 0;
2601 }
2602 
2603 static int rx_enable(struct slgt_info *info, int enable)
2604 {
2605  	unsigned long flags;
2606 	unsigned int rbuf_fill_level;
2607 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2608 	spin_lock_irqsave(&info->lock,flags);
2609 	/*
2610 	 * enable[31..16] = receive DMA buffer fill level
2611 	 * 0 = noop (leave fill level unchanged)
2612 	 * fill level must be multiple of 4 and <= buffer size
2613 	 */
2614 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2615 	if (rbuf_fill_level) {
2616 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2617 			spin_unlock_irqrestore(&info->lock, flags);
2618 			return -EINVAL;
2619 		}
2620 		info->rbuf_fill_level = rbuf_fill_level;
2621 		if (rbuf_fill_level < 128)
2622 			info->rx_pio = 1; /* PIO mode */
2623 		else
2624 			info->rx_pio = 0; /* DMA mode */
2625 		rx_stop(info); /* restart receiver to use new fill level */
2626 	}
2627 
2628 	/*
2629 	 * enable[1..0] = receiver enable command
2630 	 * 0 = disable
2631 	 * 1 = enable
2632 	 * 2 = enable or force hunt mode if already enabled
2633 	 */
2634 	enable &= 3;
2635 	if (enable) {
2636 		if (!info->rx_enabled)
2637 			rx_start(info);
2638 		else if (enable == 2) {
2639 			/* force hunt mode (write 1 to RCR[3]) */
2640 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2641 		}
2642 	} else {
2643 		if (info->rx_enabled)
2644 			rx_stop(info);
2645 	}
2646 	spin_unlock_irqrestore(&info->lock,flags);
2647 	return 0;
2648 }
2649 
2650 /*
2651  *  wait for specified event to occur
2652  */
2653 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2654 {
2655  	unsigned long flags;
2656 	int s;
2657 	int rc=0;
2658 	struct mgsl_icount cprev, cnow;
2659 	int events;
2660 	int mask;
2661 	struct	_input_signal_events oldsigs, newsigs;
2662 	DECLARE_WAITQUEUE(wait, current);
2663 
2664 	if (get_user(mask, mask_ptr))
2665 		return -EFAULT;
2666 
2667 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2668 
2669 	spin_lock_irqsave(&info->lock,flags);
2670 
2671 	/* return immediately if state matches requested events */
2672 	get_gtsignals(info);
2673 	s = info->signals;
2674 
2675 	events = mask &
2676 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2677  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2678 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2679 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2680 	if (events) {
2681 		spin_unlock_irqrestore(&info->lock,flags);
2682 		goto exit;
2683 	}
2684 
2685 	/* save current irq counts */
2686 	cprev = info->icount;
2687 	oldsigs = info->input_signal_events;
2688 
2689 	/* enable hunt and idle irqs if needed */
2690 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2691 		unsigned short val = rd_reg16(info, SCR);
2692 		if (!(val & IRQ_RXIDLE))
2693 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2694 	}
2695 
2696 	set_current_state(TASK_INTERRUPTIBLE);
2697 	add_wait_queue(&info->event_wait_q, &wait);
2698 
2699 	spin_unlock_irqrestore(&info->lock,flags);
2700 
2701 	for(;;) {
2702 		schedule();
2703 		if (signal_pending(current)) {
2704 			rc = -ERESTARTSYS;
2705 			break;
2706 		}
2707 
2708 		/* get current irq counts */
2709 		spin_lock_irqsave(&info->lock,flags);
2710 		cnow = info->icount;
2711 		newsigs = info->input_signal_events;
2712 		set_current_state(TASK_INTERRUPTIBLE);
2713 		spin_unlock_irqrestore(&info->lock,flags);
2714 
2715 		/* if no change, wait aborted for some reason */
2716 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2717 		    newsigs.dsr_down == oldsigs.dsr_down &&
2718 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2719 		    newsigs.dcd_down == oldsigs.dcd_down &&
2720 		    newsigs.cts_up   == oldsigs.cts_up   &&
2721 		    newsigs.cts_down == oldsigs.cts_down &&
2722 		    newsigs.ri_up    == oldsigs.ri_up    &&
2723 		    newsigs.ri_down  == oldsigs.ri_down  &&
2724 		    cnow.exithunt    == cprev.exithunt   &&
2725 		    cnow.rxidle      == cprev.rxidle) {
2726 			rc = -EIO;
2727 			break;
2728 		}
2729 
2730 		events = mask &
2731 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2732 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2733 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2734 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2735 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2736 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2737 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2738 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2739 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2740 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2741 		if (events)
2742 			break;
2743 
2744 		cprev = cnow;
2745 		oldsigs = newsigs;
2746 	}
2747 
2748 	remove_wait_queue(&info->event_wait_q, &wait);
2749 	set_current_state(TASK_RUNNING);
2750 
2751 
2752 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2753 		spin_lock_irqsave(&info->lock,flags);
2754 		if (!waitqueue_active(&info->event_wait_q)) {
2755 			/* disable enable exit hunt mode/idle rcvd IRQs */
2756 			wr_reg16(info, SCR,
2757 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2758 		}
2759 		spin_unlock_irqrestore(&info->lock,flags);
2760 	}
2761 exit:
2762 	if (rc == 0)
2763 		rc = put_user(events, mask_ptr);
2764 	return rc;
2765 }
2766 
2767 static int get_interface(struct slgt_info *info, int __user *if_mode)
2768 {
2769 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2770 	if (put_user(info->if_mode, if_mode))
2771 		return -EFAULT;
2772 	return 0;
2773 }
2774 
2775 static int set_interface(struct slgt_info *info, int if_mode)
2776 {
2777  	unsigned long flags;
2778 	unsigned short val;
2779 
2780 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2781 	spin_lock_irqsave(&info->lock,flags);
2782 	info->if_mode = if_mode;
2783 
2784 	msc_set_vcr(info);
2785 
2786 	/* TCR (tx control) 07  1=RTS driver control */
2787 	val = rd_reg16(info, TCR);
2788 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2789 		val |= BIT7;
2790 	else
2791 		val &= ~BIT7;
2792 	wr_reg16(info, TCR, val);
2793 
2794 	spin_unlock_irqrestore(&info->lock,flags);
2795 	return 0;
2796 }
2797 
2798 static int get_xsync(struct slgt_info *info, int __user *xsync)
2799 {
2800 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2801 	if (put_user(info->xsync, xsync))
2802 		return -EFAULT;
2803 	return 0;
2804 }
2805 
2806 /*
2807  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2808  *
2809  * sync pattern is contained in least significant bytes of value
2810  * most significant byte of sync pattern is oldest (1st sent/detected)
2811  */
2812 static int set_xsync(struct slgt_info *info, int xsync)
2813 {
2814 	unsigned long flags;
2815 
2816 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2817 	spin_lock_irqsave(&info->lock, flags);
2818 	info->xsync = xsync;
2819 	wr_reg32(info, XSR, xsync);
2820 	spin_unlock_irqrestore(&info->lock, flags);
2821 	return 0;
2822 }
2823 
2824 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2825 {
2826 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2827 	if (put_user(info->xctrl, xctrl))
2828 		return -EFAULT;
2829 	return 0;
2830 }
2831 
2832 /*
2833  * set extended control options
2834  *
2835  * xctrl[31:19] reserved, must be zero
2836  * xctrl[18:17] extended sync pattern length in bytes
2837  *              00 = 1 byte  in xsr[7:0]
2838  *              01 = 2 bytes in xsr[15:0]
2839  *              10 = 3 bytes in xsr[23:0]
2840  *              11 = 4 bytes in xsr[31:0]
2841  * xctrl[16]    1 = enable terminal count, 0=disabled
2842  * xctrl[15:0]  receive terminal count for fixed length packets
2843  *              value is count minus one (0 = 1 byte packet)
2844  *              when terminal count is reached, receiver
2845  *              automatically returns to hunt mode and receive
2846  *              FIFO contents are flushed to DMA buffers with
2847  *              end of frame (EOF) status
2848  */
2849 static int set_xctrl(struct slgt_info *info, int xctrl)
2850 {
2851 	unsigned long flags;
2852 
2853 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2854 	spin_lock_irqsave(&info->lock, flags);
2855 	info->xctrl = xctrl;
2856 	wr_reg32(info, XCR, xctrl);
2857 	spin_unlock_irqrestore(&info->lock, flags);
2858 	return 0;
2859 }
2860 
2861 /*
2862  * set general purpose IO pin state and direction
2863  *
2864  * user_gpio fields:
2865  * state   each bit indicates a pin state
2866  * smask   set bit indicates pin state to set
2867  * dir     each bit indicates a pin direction (0=input, 1=output)
2868  * dmask   set bit indicates pin direction to set
2869  */
2870 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2871 {
2872  	unsigned long flags;
2873 	struct gpio_desc gpio;
2874 	__u32 data;
2875 
2876 	if (!info->gpio_present)
2877 		return -EINVAL;
2878 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2879 		return -EFAULT;
2880 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2881 		 info->device_name, gpio.state, gpio.smask,
2882 		 gpio.dir, gpio.dmask));
2883 
2884 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2885 	if (gpio.dmask) {
2886 		data = rd_reg32(info, IODR);
2887 		data |= gpio.dmask & gpio.dir;
2888 		data &= ~(gpio.dmask & ~gpio.dir);
2889 		wr_reg32(info, IODR, data);
2890 	}
2891 	if (gpio.smask) {
2892 		data = rd_reg32(info, IOVR);
2893 		data |= gpio.smask & gpio.state;
2894 		data &= ~(gpio.smask & ~gpio.state);
2895 		wr_reg32(info, IOVR, data);
2896 	}
2897 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2898 
2899 	return 0;
2900 }
2901 
2902 /*
2903  * get general purpose IO pin state and direction
2904  */
2905 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2906 {
2907 	struct gpio_desc gpio;
2908 	if (!info->gpio_present)
2909 		return -EINVAL;
2910 	gpio.state = rd_reg32(info, IOVR);
2911 	gpio.smask = 0xffffffff;
2912 	gpio.dir   = rd_reg32(info, IODR);
2913 	gpio.dmask = 0xffffffff;
2914 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2915 		return -EFAULT;
2916 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2917 		 info->device_name, gpio.state, gpio.dir));
2918 	return 0;
2919 }
2920 
2921 /*
2922  * conditional wait facility
2923  */
2924 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2925 {
2926 	init_waitqueue_head(&w->q);
2927 	init_waitqueue_entry(&w->wait, current);
2928 	w->data = data;
2929 }
2930 
2931 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2932 {
2933 	set_current_state(TASK_INTERRUPTIBLE);
2934 	add_wait_queue(&w->q, &w->wait);
2935 	w->next = *head;
2936 	*head = w;
2937 }
2938 
2939 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2940 {
2941 	struct cond_wait *w, *prev;
2942 	remove_wait_queue(&cw->q, &cw->wait);
2943 	set_current_state(TASK_RUNNING);
2944 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2945 		if (w == cw) {
2946 			if (prev != NULL)
2947 				prev->next = w->next;
2948 			else
2949 				*head = w->next;
2950 			break;
2951 		}
2952 	}
2953 }
2954 
2955 static void flush_cond_wait(struct cond_wait **head)
2956 {
2957 	while (*head != NULL) {
2958 		wake_up_interruptible(&(*head)->q);
2959 		*head = (*head)->next;
2960 	}
2961 }
2962 
2963 /*
2964  * wait for general purpose I/O pin(s) to enter specified state
2965  *
2966  * user_gpio fields:
2967  * state - bit indicates target pin state
2968  * smask - set bit indicates watched pin
2969  *
2970  * The wait ends when at least one watched pin enters the specified
2971  * state. When 0 (no error) is returned, user_gpio->state is set to the
2972  * state of all GPIO pins when the wait ends.
2973  *
2974  * Note: Each pin may be a dedicated input, dedicated output, or
2975  * configurable input/output. The number and configuration of pins
2976  * varies with the specific adapter model. Only input pins (dedicated
2977  * or configured) can be monitored with this function.
2978  */
2979 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2980 {
2981  	unsigned long flags;
2982 	int rc = 0;
2983 	struct gpio_desc gpio;
2984 	struct cond_wait wait;
2985 	u32 state;
2986 
2987 	if (!info->gpio_present)
2988 		return -EINVAL;
2989 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2990 		return -EFAULT;
2991 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
2992 		 info->device_name, gpio.state, gpio.smask));
2993 	/* ignore output pins identified by set IODR bit */
2994 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
2995 		return -EINVAL;
2996 	init_cond_wait(&wait, gpio.smask);
2997 
2998 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2999 	/* enable interrupts for watched pins */
3000 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3001 	/* get current pin states */
3002 	state = rd_reg32(info, IOVR);
3003 
3004 	if (gpio.smask & ~(state ^ gpio.state)) {
3005 		/* already in target state */
3006 		gpio.state = state;
3007 	} else {
3008 		/* wait for target state */
3009 		add_cond_wait(&info->gpio_wait_q, &wait);
3010 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3011 		schedule();
3012 		if (signal_pending(current))
3013 			rc = -ERESTARTSYS;
3014 		else
3015 			gpio.state = wait.data;
3016 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3017 		remove_cond_wait(&info->gpio_wait_q, &wait);
3018 	}
3019 
3020 	/* disable all GPIO interrupts if no waiting processes */
3021 	if (info->gpio_wait_q == NULL)
3022 		wr_reg32(info, IOER, 0);
3023 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3024 
3025 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3026 		rc = -EFAULT;
3027 	return rc;
3028 }
3029 
3030 static int modem_input_wait(struct slgt_info *info,int arg)
3031 {
3032  	unsigned long flags;
3033 	int rc;
3034 	struct mgsl_icount cprev, cnow;
3035 	DECLARE_WAITQUEUE(wait, current);
3036 
3037 	/* save current irq counts */
3038 	spin_lock_irqsave(&info->lock,flags);
3039 	cprev = info->icount;
3040 	add_wait_queue(&info->status_event_wait_q, &wait);
3041 	set_current_state(TASK_INTERRUPTIBLE);
3042 	spin_unlock_irqrestore(&info->lock,flags);
3043 
3044 	for(;;) {
3045 		schedule();
3046 		if (signal_pending(current)) {
3047 			rc = -ERESTARTSYS;
3048 			break;
3049 		}
3050 
3051 		/* get new irq counts */
3052 		spin_lock_irqsave(&info->lock,flags);
3053 		cnow = info->icount;
3054 		set_current_state(TASK_INTERRUPTIBLE);
3055 		spin_unlock_irqrestore(&info->lock,flags);
3056 
3057 		/* if no change, wait aborted for some reason */
3058 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3059 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3060 			rc = -EIO;
3061 			break;
3062 		}
3063 
3064 		/* check for change in caller specified modem input */
3065 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3066 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3067 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3068 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3069 			rc = 0;
3070 			break;
3071 		}
3072 
3073 		cprev = cnow;
3074 	}
3075 	remove_wait_queue(&info->status_event_wait_q, &wait);
3076 	set_current_state(TASK_RUNNING);
3077 	return rc;
3078 }
3079 
3080 /*
3081  *  return state of serial control and status signals
3082  */
3083 static int tiocmget(struct tty_struct *tty)
3084 {
3085 	struct slgt_info *info = tty->driver_data;
3086 	unsigned int result;
3087  	unsigned long flags;
3088 
3089 	spin_lock_irqsave(&info->lock,flags);
3090  	get_gtsignals(info);
3091 	spin_unlock_irqrestore(&info->lock,flags);
3092 
3093 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3094 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3095 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3096 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3097 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3098 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3099 
3100 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3101 	return result;
3102 }
3103 
3104 /*
3105  * set modem control signals (DTR/RTS)
3106  *
3107  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3108  *		TIOCMSET = set/clear signal values
3109  * 	value	bit mask for command
3110  */
3111 static int tiocmset(struct tty_struct *tty,
3112 		    unsigned int set, unsigned int clear)
3113 {
3114 	struct slgt_info *info = tty->driver_data;
3115  	unsigned long flags;
3116 
3117 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3118 
3119 	if (set & TIOCM_RTS)
3120 		info->signals |= SerialSignal_RTS;
3121 	if (set & TIOCM_DTR)
3122 		info->signals |= SerialSignal_DTR;
3123 	if (clear & TIOCM_RTS)
3124 		info->signals &= ~SerialSignal_RTS;
3125 	if (clear & TIOCM_DTR)
3126 		info->signals &= ~SerialSignal_DTR;
3127 
3128 	spin_lock_irqsave(&info->lock,flags);
3129 	set_gtsignals(info);
3130 	spin_unlock_irqrestore(&info->lock,flags);
3131 	return 0;
3132 }
3133 
3134 static int carrier_raised(struct tty_port *port)
3135 {
3136 	unsigned long flags;
3137 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3138 
3139 	spin_lock_irqsave(&info->lock,flags);
3140 	get_gtsignals(info);
3141 	spin_unlock_irqrestore(&info->lock,flags);
3142 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3143 }
3144 
3145 static void dtr_rts(struct tty_port *port, int on)
3146 {
3147 	unsigned long flags;
3148 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3149 
3150 	spin_lock_irqsave(&info->lock,flags);
3151 	if (on)
3152 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3153 	else
3154 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3155 	set_gtsignals(info);
3156 	spin_unlock_irqrestore(&info->lock,flags);
3157 }
3158 
3159 
3160 /*
3161  *  block current process until the device is ready to open
3162  */
3163 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3164 			   struct slgt_info *info)
3165 {
3166 	DECLARE_WAITQUEUE(wait, current);
3167 	int		retval;
3168 	bool		do_clocal = false;
3169 	unsigned long	flags;
3170 	int		cd;
3171 	struct tty_port *port = &info->port;
3172 
3173 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3174 
3175 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3176 		/* nonblock mode is set or port is not enabled */
3177 		tty_port_set_active(port, 1);
3178 		return 0;
3179 	}
3180 
3181 	if (C_CLOCAL(tty))
3182 		do_clocal = true;
3183 
3184 	/* Wait for carrier detect and the line to become
3185 	 * free (i.e., not in use by the callout).  While we are in
3186 	 * this loop, port->count is dropped by one, so that
3187 	 * close() knows when to free things.  We restore it upon
3188 	 * exit, either normal or abnormal.
3189 	 */
3190 
3191 	retval = 0;
3192 	add_wait_queue(&port->open_wait, &wait);
3193 
3194 	spin_lock_irqsave(&info->lock, flags);
3195 	port->count--;
3196 	spin_unlock_irqrestore(&info->lock, flags);
3197 	port->blocked_open++;
3198 
3199 	while (1) {
3200 		if (C_BAUD(tty) && tty_port_initialized(port))
3201 			tty_port_raise_dtr_rts(port);
3202 
3203 		set_current_state(TASK_INTERRUPTIBLE);
3204 
3205 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3206 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3207 					-EAGAIN : -ERESTARTSYS;
3208 			break;
3209 		}
3210 
3211 		cd = tty_port_carrier_raised(port);
3212 		if (do_clocal || cd)
3213 			break;
3214 
3215 		if (signal_pending(current)) {
3216 			retval = -ERESTARTSYS;
3217 			break;
3218 		}
3219 
3220 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3221 		tty_unlock(tty);
3222 		schedule();
3223 		tty_lock(tty);
3224 	}
3225 
3226 	set_current_state(TASK_RUNNING);
3227 	remove_wait_queue(&port->open_wait, &wait);
3228 
3229 	if (!tty_hung_up_p(filp))
3230 		port->count++;
3231 	port->blocked_open--;
3232 
3233 	if (!retval)
3234 		tty_port_set_active(port, 1);
3235 
3236 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3237 	return retval;
3238 }
3239 
3240 /*
3241  * allocate buffers used for calling line discipline receive_buf
3242  * directly in synchronous mode
3243  * note: add 5 bytes to max frame size to allow appending
3244  * 32-bit CRC and status byte when configured to do so
3245  */
3246 static int alloc_tmp_rbuf(struct slgt_info *info)
3247 {
3248 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3249 	if (info->tmp_rbuf == NULL)
3250 		return -ENOMEM;
3251 	/* unused flag buffer to satisfy receive_buf calling interface */
3252 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3253 	if (!info->flag_buf) {
3254 		kfree(info->tmp_rbuf);
3255 		info->tmp_rbuf = NULL;
3256 		return -ENOMEM;
3257 	}
3258 	return 0;
3259 }
3260 
3261 static void free_tmp_rbuf(struct slgt_info *info)
3262 {
3263 	kfree(info->tmp_rbuf);
3264 	info->tmp_rbuf = NULL;
3265 	kfree(info->flag_buf);
3266 	info->flag_buf = NULL;
3267 }
3268 
3269 /*
3270  * allocate DMA descriptor lists.
3271  */
3272 static int alloc_desc(struct slgt_info *info)
3273 {
3274 	unsigned int i;
3275 	unsigned int pbufs;
3276 
3277 	/* allocate memory to hold descriptor lists */
3278 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3279 					&info->bufs_dma_addr, GFP_KERNEL);
3280 	if (info->bufs == NULL)
3281 		return -ENOMEM;
3282 
3283 	info->rbufs = (struct slgt_desc*)info->bufs;
3284 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3285 
3286 	pbufs = (unsigned int)info->bufs_dma_addr;
3287 
3288 	/*
3289 	 * Build circular lists of descriptors
3290 	 */
3291 
3292 	for (i=0; i < info->rbuf_count; i++) {
3293 		/* physical address of this descriptor */
3294 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3295 
3296 		/* physical address of next descriptor */
3297 		if (i == info->rbuf_count - 1)
3298 			info->rbufs[i].next = cpu_to_le32(pbufs);
3299 		else
3300 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3301 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3302 	}
3303 
3304 	for (i=0; i < info->tbuf_count; i++) {
3305 		/* physical address of this descriptor */
3306 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3307 
3308 		/* physical address of next descriptor */
3309 		if (i == info->tbuf_count - 1)
3310 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3311 		else
3312 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3313 	}
3314 
3315 	return 0;
3316 }
3317 
3318 static void free_desc(struct slgt_info *info)
3319 {
3320 	if (info->bufs != NULL) {
3321 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3322 				  info->bufs, info->bufs_dma_addr);
3323 		info->bufs  = NULL;
3324 		info->rbufs = NULL;
3325 		info->tbufs = NULL;
3326 	}
3327 }
3328 
3329 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3330 {
3331 	int i;
3332 	for (i=0; i < count; i++) {
3333 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3334 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3335 		if (!bufs[i].buf)
3336 			return -ENOMEM;
3337 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3338 	}
3339 	return 0;
3340 }
3341 
3342 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3343 {
3344 	int i;
3345 	for (i=0; i < count; i++) {
3346 		if (bufs[i].buf == NULL)
3347 			continue;
3348 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3349 				  bufs[i].buf_dma_addr);
3350 		bufs[i].buf = NULL;
3351 	}
3352 }
3353 
3354 static int alloc_dma_bufs(struct slgt_info *info)
3355 {
3356 	info->rbuf_count = 32;
3357 	info->tbuf_count = 32;
3358 
3359 	if (alloc_desc(info) < 0 ||
3360 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3361 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3362 	    alloc_tmp_rbuf(info) < 0) {
3363 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3364 		return -ENOMEM;
3365 	}
3366 	reset_rbufs(info);
3367 	return 0;
3368 }
3369 
3370 static void free_dma_bufs(struct slgt_info *info)
3371 {
3372 	if (info->bufs) {
3373 		free_bufs(info, info->rbufs, info->rbuf_count);
3374 		free_bufs(info, info->tbufs, info->tbuf_count);
3375 		free_desc(info);
3376 	}
3377 	free_tmp_rbuf(info);
3378 }
3379 
3380 static int claim_resources(struct slgt_info *info)
3381 {
3382 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3383 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3384 			info->device_name, info->phys_reg_addr));
3385 		info->init_error = DiagStatus_AddressConflict;
3386 		goto errout;
3387 	}
3388 	else
3389 		info->reg_addr_requested = true;
3390 
3391 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3392 	if (!info->reg_addr) {
3393 		DBGERR(("%s can't map device registers, addr=%08X\n",
3394 			info->device_name, info->phys_reg_addr));
3395 		info->init_error = DiagStatus_CantAssignPciResources;
3396 		goto errout;
3397 	}
3398 	return 0;
3399 
3400 errout:
3401 	release_resources(info);
3402 	return -ENODEV;
3403 }
3404 
3405 static void release_resources(struct slgt_info *info)
3406 {
3407 	if (info->irq_requested) {
3408 		free_irq(info->irq_level, info);
3409 		info->irq_requested = false;
3410 	}
3411 
3412 	if (info->reg_addr_requested) {
3413 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3414 		info->reg_addr_requested = false;
3415 	}
3416 
3417 	if (info->reg_addr) {
3418 		iounmap(info->reg_addr);
3419 		info->reg_addr = NULL;
3420 	}
3421 }
3422 
3423 /* Add the specified device instance data structure to the
3424  * global linked list of devices and increment the device count.
3425  */
3426 static void add_device(struct slgt_info *info)
3427 {
3428 	char *devstr;
3429 
3430 	info->next_device = NULL;
3431 	info->line = slgt_device_count;
3432 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3433 
3434 	if (info->line < MAX_DEVICES) {
3435 		if (maxframe[info->line])
3436 			info->max_frame_size = maxframe[info->line];
3437 	}
3438 
3439 	slgt_device_count++;
3440 
3441 	if (!slgt_device_list)
3442 		slgt_device_list = info;
3443 	else {
3444 		struct slgt_info *current_dev = slgt_device_list;
3445 		while(current_dev->next_device)
3446 			current_dev = current_dev->next_device;
3447 		current_dev->next_device = info;
3448 	}
3449 
3450 	if (info->max_frame_size < 4096)
3451 		info->max_frame_size = 4096;
3452 	else if (info->max_frame_size > 65535)
3453 		info->max_frame_size = 65535;
3454 
3455 	switch(info->pdev->device) {
3456 	case SYNCLINK_GT_DEVICE_ID:
3457 		devstr = "GT";
3458 		break;
3459 	case SYNCLINK_GT2_DEVICE_ID:
3460 		devstr = "GT2";
3461 		break;
3462 	case SYNCLINK_GT4_DEVICE_ID:
3463 		devstr = "GT4";
3464 		break;
3465 	case SYNCLINK_AC_DEVICE_ID:
3466 		devstr = "AC";
3467 		info->params.mode = MGSL_MODE_ASYNC;
3468 		break;
3469 	default:
3470 		devstr = "(unknown model)";
3471 	}
3472 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3473 		devstr, info->device_name, info->phys_reg_addr,
3474 		info->irq_level, info->max_frame_size);
3475 
3476 #if SYNCLINK_GENERIC_HDLC
3477 	hdlcdev_init(info);
3478 #endif
3479 }
3480 
3481 static const struct tty_port_operations slgt_port_ops = {
3482 	.carrier_raised = carrier_raised,
3483 	.dtr_rts = dtr_rts,
3484 };
3485 
3486 /*
3487  *  allocate device instance structure, return NULL on failure
3488  */
3489 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3490 {
3491 	struct slgt_info *info;
3492 
3493 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3494 
3495 	if (!info) {
3496 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3497 			driver_name, adapter_num, port_num));
3498 	} else {
3499 		tty_port_init(&info->port);
3500 		info->port.ops = &slgt_port_ops;
3501 		info->magic = MGSL_MAGIC;
3502 		INIT_WORK(&info->task, bh_handler);
3503 		info->max_frame_size = 4096;
3504 		info->base_clock = 14745600;
3505 		info->rbuf_fill_level = DMABUFSIZE;
3506 		init_waitqueue_head(&info->status_event_wait_q);
3507 		init_waitqueue_head(&info->event_wait_q);
3508 		spin_lock_init(&info->netlock);
3509 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3510 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3511 		info->adapter_num = adapter_num;
3512 		info->port_num = port_num;
3513 
3514 		timer_setup(&info->tx_timer, tx_timeout, 0);
3515 		timer_setup(&info->rx_timer, rx_timeout, 0);
3516 
3517 		/* Copy configuration info to device instance data */
3518 		info->pdev = pdev;
3519 		info->irq_level = pdev->irq;
3520 		info->phys_reg_addr = pci_resource_start(pdev,0);
3521 
3522 		info->bus_type = MGSL_BUS_TYPE_PCI;
3523 		info->irq_flags = IRQF_SHARED;
3524 
3525 		info->init_error = -1; /* assume error, set to 0 on successful init */
3526 	}
3527 
3528 	return info;
3529 }
3530 
3531 static void device_init(int adapter_num, struct pci_dev *pdev)
3532 {
3533 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3534 	int i;
3535 	int port_count = 1;
3536 
3537 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3538 		port_count = 2;
3539 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3540 		port_count = 4;
3541 
3542 	/* allocate device instances for all ports */
3543 	for (i=0; i < port_count; ++i) {
3544 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3545 		if (port_array[i] == NULL) {
3546 			for (--i; i >= 0; --i) {
3547 				tty_port_destroy(&port_array[i]->port);
3548 				kfree(port_array[i]);
3549 			}
3550 			return;
3551 		}
3552 	}
3553 
3554 	/* give copy of port_array to all ports and add to device list  */
3555 	for (i=0; i < port_count; ++i) {
3556 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3557 		add_device(port_array[i]);
3558 		port_array[i]->port_count = port_count;
3559 		spin_lock_init(&port_array[i]->lock);
3560 	}
3561 
3562 	/* Allocate and claim adapter resources */
3563 	if (!claim_resources(port_array[0])) {
3564 
3565 		alloc_dma_bufs(port_array[0]);
3566 
3567 		/* copy resource information from first port to others */
3568 		for (i = 1; i < port_count; ++i) {
3569 			port_array[i]->irq_level = port_array[0]->irq_level;
3570 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3571 			alloc_dma_bufs(port_array[i]);
3572 		}
3573 
3574 		if (request_irq(port_array[0]->irq_level,
3575 					slgt_interrupt,
3576 					port_array[0]->irq_flags,
3577 					port_array[0]->device_name,
3578 					port_array[0]) < 0) {
3579 			DBGERR(("%s request_irq failed IRQ=%d\n",
3580 				port_array[0]->device_name,
3581 				port_array[0]->irq_level));
3582 		} else {
3583 			port_array[0]->irq_requested = true;
3584 			adapter_test(port_array[0]);
3585 			for (i=1 ; i < port_count ; i++) {
3586 				port_array[i]->init_error = port_array[0]->init_error;
3587 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3588 			}
3589 		}
3590 	}
3591 
3592 	for (i = 0; i < port_count; ++i) {
3593 		struct slgt_info *info = port_array[i];
3594 		tty_port_register_device(&info->port, serial_driver, info->line,
3595 				&info->pdev->dev);
3596 	}
3597 }
3598 
3599 static int init_one(struct pci_dev *dev,
3600 			      const struct pci_device_id *ent)
3601 {
3602 	if (pci_enable_device(dev)) {
3603 		printk("error enabling pci device %p\n", dev);
3604 		return -EIO;
3605 	}
3606 	pci_set_master(dev);
3607 	device_init(slgt_device_count, dev);
3608 	return 0;
3609 }
3610 
3611 static void remove_one(struct pci_dev *dev)
3612 {
3613 }
3614 
3615 static const struct tty_operations ops = {
3616 	.open = open,
3617 	.close = close,
3618 	.write = write,
3619 	.put_char = put_char,
3620 	.flush_chars = flush_chars,
3621 	.write_room = write_room,
3622 	.chars_in_buffer = chars_in_buffer,
3623 	.flush_buffer = flush_buffer,
3624 	.ioctl = ioctl,
3625 	.compat_ioctl = slgt_compat_ioctl,
3626 	.throttle = throttle,
3627 	.unthrottle = unthrottle,
3628 	.send_xchar = send_xchar,
3629 	.break_ctl = set_break,
3630 	.wait_until_sent = wait_until_sent,
3631 	.set_termios = set_termios,
3632 	.stop = tx_hold,
3633 	.start = tx_release,
3634 	.hangup = hangup,
3635 	.tiocmget = tiocmget,
3636 	.tiocmset = tiocmset,
3637 	.get_icount = get_icount,
3638 	.proc_show = synclink_gt_proc_show,
3639 };
3640 
3641 static void slgt_cleanup(void)
3642 {
3643 	struct slgt_info *info;
3644 	struct slgt_info *tmp;
3645 
3646 	printk(KERN_INFO "unload %s\n", driver_name);
3647 
3648 	if (serial_driver) {
3649 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3650 			tty_unregister_device(serial_driver, info->line);
3651 		tty_unregister_driver(serial_driver);
3652 		tty_driver_kref_put(serial_driver);
3653 	}
3654 
3655 	/* reset devices */
3656 	info = slgt_device_list;
3657 	while(info) {
3658 		reset_port(info);
3659 		info = info->next_device;
3660 	}
3661 
3662 	/* release devices */
3663 	info = slgt_device_list;
3664 	while(info) {
3665 #if SYNCLINK_GENERIC_HDLC
3666 		hdlcdev_exit(info);
3667 #endif
3668 		free_dma_bufs(info);
3669 		free_tmp_rbuf(info);
3670 		if (info->port_num == 0)
3671 			release_resources(info);
3672 		tmp = info;
3673 		info = info->next_device;
3674 		tty_port_destroy(&tmp->port);
3675 		kfree(tmp);
3676 	}
3677 
3678 	if (pci_registered)
3679 		pci_unregister_driver(&pci_driver);
3680 }
3681 
3682 /*
3683  *  Driver initialization entry point.
3684  */
3685 static int __init slgt_init(void)
3686 {
3687 	int rc;
3688 
3689 	printk(KERN_INFO "%s\n", driver_name);
3690 
3691 	serial_driver = tty_alloc_driver(MAX_DEVICES, TTY_DRIVER_REAL_RAW |
3692 			TTY_DRIVER_DYNAMIC_DEV);
3693 	if (IS_ERR(serial_driver)) {
3694 		printk("%s can't allocate tty driver\n", driver_name);
3695 		return PTR_ERR(serial_driver);
3696 	}
3697 
3698 	/* Initialize the tty_driver structure */
3699 
3700 	serial_driver->driver_name = slgt_driver_name;
3701 	serial_driver->name = tty_dev_prefix;
3702 	serial_driver->major = ttymajor;
3703 	serial_driver->minor_start = 64;
3704 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3705 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3706 	serial_driver->init_termios = tty_std_termios;
3707 	serial_driver->init_termios.c_cflag =
3708 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3709 	serial_driver->init_termios.c_ispeed = 9600;
3710 	serial_driver->init_termios.c_ospeed = 9600;
3711 	tty_set_operations(serial_driver, &ops);
3712 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3713 		DBGERR(("%s can't register serial driver\n", driver_name));
3714 		tty_driver_kref_put(serial_driver);
3715 		serial_driver = NULL;
3716 		goto error;
3717 	}
3718 
3719 	printk(KERN_INFO "%s, tty major#%d\n",
3720 	       driver_name, serial_driver->major);
3721 
3722 	slgt_device_count = 0;
3723 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3724 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3725 		goto error;
3726 	}
3727 	pci_registered = true;
3728 
3729 	if (!slgt_device_list)
3730 		printk("%s no devices found\n",driver_name);
3731 
3732 	return 0;
3733 
3734 error:
3735 	slgt_cleanup();
3736 	return rc;
3737 }
3738 
3739 static void __exit slgt_exit(void)
3740 {
3741 	slgt_cleanup();
3742 }
3743 
3744 module_init(slgt_init);
3745 module_exit(slgt_exit);
3746 
3747 /*
3748  * register access routines
3749  */
3750 
3751 #define CALC_REGADDR() \
3752 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3753 	if (addr >= 0x80) \
3754 		reg_addr += (info->port_num) * 32; \
3755 	else if (addr >= 0x40)	\
3756 		reg_addr += (info->port_num) * 16;
3757 
3758 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3759 {
3760 	CALC_REGADDR();
3761 	return readb((void __iomem *)reg_addr);
3762 }
3763 
3764 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3765 {
3766 	CALC_REGADDR();
3767 	writeb(value, (void __iomem *)reg_addr);
3768 }
3769 
3770 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3771 {
3772 	CALC_REGADDR();
3773 	return readw((void __iomem *)reg_addr);
3774 }
3775 
3776 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3777 {
3778 	CALC_REGADDR();
3779 	writew(value, (void __iomem *)reg_addr);
3780 }
3781 
3782 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3783 {
3784 	CALC_REGADDR();
3785 	return readl((void __iomem *)reg_addr);
3786 }
3787 
3788 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3789 {
3790 	CALC_REGADDR();
3791 	writel(value, (void __iomem *)reg_addr);
3792 }
3793 
3794 static void rdma_reset(struct slgt_info *info)
3795 {
3796 	unsigned int i;
3797 
3798 	/* set reset bit */
3799 	wr_reg32(info, RDCSR, BIT1);
3800 
3801 	/* wait for enable bit cleared */
3802 	for(i=0 ; i < 1000 ; i++)
3803 		if (!(rd_reg32(info, RDCSR) & BIT0))
3804 			break;
3805 }
3806 
3807 static void tdma_reset(struct slgt_info *info)
3808 {
3809 	unsigned int i;
3810 
3811 	/* set reset bit */
3812 	wr_reg32(info, TDCSR, BIT1);
3813 
3814 	/* wait for enable bit cleared */
3815 	for(i=0 ; i < 1000 ; i++)
3816 		if (!(rd_reg32(info, TDCSR) & BIT0))
3817 			break;
3818 }
3819 
3820 /*
3821  * enable internal loopback
3822  * TxCLK and RxCLK are generated from BRG
3823  * and TxD is looped back to RxD internally.
3824  */
3825 static void enable_loopback(struct slgt_info *info)
3826 {
3827 	/* SCR (serial control) BIT2=loopback enable */
3828 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3829 
3830 	if (info->params.mode != MGSL_MODE_ASYNC) {
3831 		/* CCR (clock control)
3832 		 * 07..05  tx clock source (010 = BRG)
3833 		 * 04..02  rx clock source (010 = BRG)
3834 		 * 01      auxclk enable   (0 = disable)
3835 		 * 00      BRG enable      (1 = enable)
3836 		 *
3837 		 * 0100 1001
3838 		 */
3839 		wr_reg8(info, CCR, 0x49);
3840 
3841 		/* set speed if available, otherwise use default */
3842 		if (info->params.clock_speed)
3843 			set_rate(info, info->params.clock_speed);
3844 		else
3845 			set_rate(info, 3686400);
3846 	}
3847 }
3848 
3849 /*
3850  *  set baud rate generator to specified rate
3851  */
3852 static void set_rate(struct slgt_info *info, u32 rate)
3853 {
3854 	unsigned int div;
3855 	unsigned int osc = info->base_clock;
3856 
3857 	/* div = osc/rate - 1
3858 	 *
3859 	 * Round div up if osc/rate is not integer to
3860 	 * force to next slowest rate.
3861 	 */
3862 
3863 	if (rate) {
3864 		div = osc/rate;
3865 		if (!(osc % rate) && div)
3866 			div--;
3867 		wr_reg16(info, BDR, (unsigned short)div);
3868 	}
3869 }
3870 
3871 static void rx_stop(struct slgt_info *info)
3872 {
3873 	unsigned short val;
3874 
3875 	/* disable and reset receiver */
3876 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3877 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3878 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3879 
3880 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3881 
3882 	/* clear pending rx interrupts */
3883 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3884 
3885 	rdma_reset(info);
3886 
3887 	info->rx_enabled = false;
3888 	info->rx_restart = false;
3889 }
3890 
3891 static void rx_start(struct slgt_info *info)
3892 {
3893 	unsigned short val;
3894 
3895 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3896 
3897 	/* clear pending rx overrun IRQ */
3898 	wr_reg16(info, SSR, IRQ_RXOVER);
3899 
3900 	/* reset and disable receiver */
3901 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3902 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3903 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3904 
3905 	rdma_reset(info);
3906 	reset_rbufs(info);
3907 
3908 	if (info->rx_pio) {
3909 		/* rx request when rx FIFO not empty */
3910 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3911 		slgt_irq_on(info, IRQ_RXDATA);
3912 		if (info->params.mode == MGSL_MODE_ASYNC) {
3913 			/* enable saving of rx status */
3914 			wr_reg32(info, RDCSR, BIT6);
3915 		}
3916 	} else {
3917 		/* rx request when rx FIFO half full */
3918 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3919 		/* set 1st descriptor address */
3920 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3921 
3922 		if (info->params.mode != MGSL_MODE_ASYNC) {
3923 			/* enable rx DMA and DMA interrupt */
3924 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3925 		} else {
3926 			/* enable saving of rx status, rx DMA and DMA interrupt */
3927 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3928 		}
3929 	}
3930 
3931 	slgt_irq_on(info, IRQ_RXOVER);
3932 
3933 	/* enable receiver */
3934 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3935 
3936 	info->rx_restart = false;
3937 	info->rx_enabled = true;
3938 }
3939 
3940 static void tx_start(struct slgt_info *info)
3941 {
3942 	if (!info->tx_enabled) {
3943 		wr_reg16(info, TCR,
3944 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3945 		info->tx_enabled = true;
3946 	}
3947 
3948 	if (desc_count(info->tbufs[info->tbuf_start])) {
3949 		info->drop_rts_on_tx_done = false;
3950 
3951 		if (info->params.mode != MGSL_MODE_ASYNC) {
3952 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3953 				get_gtsignals(info);
3954 				if (!(info->signals & SerialSignal_RTS)) {
3955 					info->signals |= SerialSignal_RTS;
3956 					set_gtsignals(info);
3957 					info->drop_rts_on_tx_done = true;
3958 				}
3959 			}
3960 
3961 			slgt_irq_off(info, IRQ_TXDATA);
3962 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3963 			/* clear tx idle and underrun status bits */
3964 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3965 		} else {
3966 			slgt_irq_off(info, IRQ_TXDATA);
3967 			slgt_irq_on(info, IRQ_TXIDLE);
3968 			/* clear tx idle status bit */
3969 			wr_reg16(info, SSR, IRQ_TXIDLE);
3970 		}
3971 		/* set 1st descriptor address and start DMA */
3972 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3973 		wr_reg32(info, TDCSR, BIT2 + BIT0);
3974 		info->tx_active = true;
3975 	}
3976 }
3977 
3978 static void tx_stop(struct slgt_info *info)
3979 {
3980 	unsigned short val;
3981 
3982 	del_timer(&info->tx_timer);
3983 
3984 	tdma_reset(info);
3985 
3986 	/* reset and disable transmitter */
3987 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
3988 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
3989 
3990 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
3991 
3992 	/* clear tx idle and underrun status bit */
3993 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3994 
3995 	reset_tbufs(info);
3996 
3997 	info->tx_enabled = false;
3998 	info->tx_active = false;
3999 }
4000 
4001 static void reset_port(struct slgt_info *info)
4002 {
4003 	if (!info->reg_addr)
4004 		return;
4005 
4006 	tx_stop(info);
4007 	rx_stop(info);
4008 
4009 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4010 	set_gtsignals(info);
4011 
4012 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4013 }
4014 
4015 static void reset_adapter(struct slgt_info *info)
4016 {
4017 	int i;
4018 	for (i=0; i < info->port_count; ++i) {
4019 		if (info->port_array[i])
4020 			reset_port(info->port_array[i]);
4021 	}
4022 }
4023 
4024 static void async_mode(struct slgt_info *info)
4025 {
4026   	unsigned short val;
4027 
4028 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4029 	tx_stop(info);
4030 	rx_stop(info);
4031 
4032 	/* TCR (tx control)
4033 	 *
4034 	 * 15..13  mode, 010=async
4035 	 * 12..10  encoding, 000=NRZ
4036 	 * 09      parity enable
4037 	 * 08      1=odd parity, 0=even parity
4038 	 * 07      1=RTS driver control
4039 	 * 06      1=break enable
4040 	 * 05..04  character length
4041 	 *         00=5 bits
4042 	 *         01=6 bits
4043 	 *         10=7 bits
4044 	 *         11=8 bits
4045 	 * 03      0=1 stop bit, 1=2 stop bits
4046 	 * 02      reset
4047 	 * 01      enable
4048 	 * 00      auto-CTS enable
4049 	 */
4050 	val = 0x4000;
4051 
4052 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4053 		val |= BIT7;
4054 
4055 	if (info->params.parity != ASYNC_PARITY_NONE) {
4056 		val |= BIT9;
4057 		if (info->params.parity == ASYNC_PARITY_ODD)
4058 			val |= BIT8;
4059 	}
4060 
4061 	switch (info->params.data_bits)
4062 	{
4063 	case 6: val |= BIT4; break;
4064 	case 7: val |= BIT5; break;
4065 	case 8: val |= BIT5 + BIT4; break;
4066 	}
4067 
4068 	if (info->params.stop_bits != 1)
4069 		val |= BIT3;
4070 
4071 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4072 		val |= BIT0;
4073 
4074 	wr_reg16(info, TCR, val);
4075 
4076 	/* RCR (rx control)
4077 	 *
4078 	 * 15..13  mode, 010=async
4079 	 * 12..10  encoding, 000=NRZ
4080 	 * 09      parity enable
4081 	 * 08      1=odd parity, 0=even parity
4082 	 * 07..06  reserved, must be 0
4083 	 * 05..04  character length
4084 	 *         00=5 bits
4085 	 *         01=6 bits
4086 	 *         10=7 bits
4087 	 *         11=8 bits
4088 	 * 03      reserved, must be zero
4089 	 * 02      reset
4090 	 * 01      enable
4091 	 * 00      auto-DCD enable
4092 	 */
4093 	val = 0x4000;
4094 
4095 	if (info->params.parity != ASYNC_PARITY_NONE) {
4096 		val |= BIT9;
4097 		if (info->params.parity == ASYNC_PARITY_ODD)
4098 			val |= BIT8;
4099 	}
4100 
4101 	switch (info->params.data_bits)
4102 	{
4103 	case 6: val |= BIT4; break;
4104 	case 7: val |= BIT5; break;
4105 	case 8: val |= BIT5 + BIT4; break;
4106 	}
4107 
4108 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4109 		val |= BIT0;
4110 
4111 	wr_reg16(info, RCR, val);
4112 
4113 	/* CCR (clock control)
4114 	 *
4115 	 * 07..05  011 = tx clock source is BRG/16
4116 	 * 04..02  010 = rx clock source is BRG
4117 	 * 01      0 = auxclk disabled
4118 	 * 00      1 = BRG enabled
4119 	 *
4120 	 * 0110 1001
4121 	 */
4122 	wr_reg8(info, CCR, 0x69);
4123 
4124 	msc_set_vcr(info);
4125 
4126 	/* SCR (serial control)
4127 	 *
4128 	 * 15  1=tx req on FIFO half empty
4129 	 * 14  1=rx req on FIFO half full
4130 	 * 13  tx data  IRQ enable
4131 	 * 12  tx idle  IRQ enable
4132 	 * 11  rx break on IRQ enable
4133 	 * 10  rx data  IRQ enable
4134 	 * 09  rx break off IRQ enable
4135 	 * 08  overrun  IRQ enable
4136 	 * 07  DSR      IRQ enable
4137 	 * 06  CTS      IRQ enable
4138 	 * 05  DCD      IRQ enable
4139 	 * 04  RI       IRQ enable
4140 	 * 03  0=16x sampling, 1=8x sampling
4141 	 * 02  1=txd->rxd internal loopback enable
4142 	 * 01  reserved, must be zero
4143 	 * 00  1=master IRQ enable
4144 	 */
4145 	val = BIT15 + BIT14 + BIT0;
4146 	/* JCR[8] : 1 = x8 async mode feature available */
4147 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4148 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4149 	     (info->base_clock % (info->params.data_rate * 16)))) {
4150 		/* use 8x sampling */
4151 		val |= BIT3;
4152 		set_rate(info, info->params.data_rate * 8);
4153 	} else {
4154 		/* use 16x sampling */
4155 		set_rate(info, info->params.data_rate * 16);
4156 	}
4157 	wr_reg16(info, SCR, val);
4158 
4159 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4160 
4161 	if (info->params.loopback)
4162 		enable_loopback(info);
4163 }
4164 
4165 static void sync_mode(struct slgt_info *info)
4166 {
4167 	unsigned short val;
4168 
4169 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4170 	tx_stop(info);
4171 	rx_stop(info);
4172 
4173 	/* TCR (tx control)
4174 	 *
4175 	 * 15..13  mode
4176 	 *         000=HDLC/SDLC
4177 	 *         001=raw bit synchronous
4178 	 *         010=asynchronous/isochronous
4179 	 *         011=monosync byte synchronous
4180 	 *         100=bisync byte synchronous
4181 	 *         101=xsync byte synchronous
4182 	 * 12..10  encoding
4183 	 * 09      CRC enable
4184 	 * 08      CRC32
4185 	 * 07      1=RTS driver control
4186 	 * 06      preamble enable
4187 	 * 05..04  preamble length
4188 	 * 03      share open/close flag
4189 	 * 02      reset
4190 	 * 01      enable
4191 	 * 00      auto-CTS enable
4192 	 */
4193 	val = BIT2;
4194 
4195 	switch(info->params.mode) {
4196 	case MGSL_MODE_XSYNC:
4197 		val |= BIT15 + BIT13;
4198 		break;
4199 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4200 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4201 	case MGSL_MODE_RAW:      val |= BIT13; break;
4202 	}
4203 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4204 		val |= BIT7;
4205 
4206 	switch(info->params.encoding)
4207 	{
4208 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4209 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4210 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4211 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4212 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4213 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4214 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4215 	}
4216 
4217 	switch (info->params.crc_type & HDLC_CRC_MASK)
4218 	{
4219 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4220 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4221 	}
4222 
4223 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4224 		val |= BIT6;
4225 
4226 	switch (info->params.preamble_length)
4227 	{
4228 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4229 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4230 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4231 	}
4232 
4233 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4234 		val |= BIT0;
4235 
4236 	wr_reg16(info, TCR, val);
4237 
4238 	/* TPR (transmit preamble) */
4239 
4240 	switch (info->params.preamble)
4241 	{
4242 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4243 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4244 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4245 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4246 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4247 	default:                          val = 0x7e; break;
4248 	}
4249 	wr_reg8(info, TPR, (unsigned char)val);
4250 
4251 	/* RCR (rx control)
4252 	 *
4253 	 * 15..13  mode
4254 	 *         000=HDLC/SDLC
4255 	 *         001=raw bit synchronous
4256 	 *         010=asynchronous/isochronous
4257 	 *         011=monosync byte synchronous
4258 	 *         100=bisync byte synchronous
4259 	 *         101=xsync byte synchronous
4260 	 * 12..10  encoding
4261 	 * 09      CRC enable
4262 	 * 08      CRC32
4263 	 * 07..03  reserved, must be 0
4264 	 * 02      reset
4265 	 * 01      enable
4266 	 * 00      auto-DCD enable
4267 	 */
4268 	val = 0;
4269 
4270 	switch(info->params.mode) {
4271 	case MGSL_MODE_XSYNC:
4272 		val |= BIT15 + BIT13;
4273 		break;
4274 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4275 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4276 	case MGSL_MODE_RAW:      val |= BIT13; break;
4277 	}
4278 
4279 	switch(info->params.encoding)
4280 	{
4281 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4282 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4283 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4284 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4285 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4286 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4287 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4288 	}
4289 
4290 	switch (info->params.crc_type & HDLC_CRC_MASK)
4291 	{
4292 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4293 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4294 	}
4295 
4296 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4297 		val |= BIT0;
4298 
4299 	wr_reg16(info, RCR, val);
4300 
4301 	/* CCR (clock control)
4302 	 *
4303 	 * 07..05  tx clock source
4304 	 * 04..02  rx clock source
4305 	 * 01      auxclk enable
4306 	 * 00      BRG enable
4307 	 */
4308 	val = 0;
4309 
4310 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4311 	{
4312 		// when RxC source is DPLL, BRG generates 16X DPLL
4313 		// reference clock, so take TxC from BRG/16 to get
4314 		// transmit clock at actual data rate
4315 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4316 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4317 		else
4318 			val |= BIT6;	/* 010, txclk = BRG */
4319 	}
4320 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4321 		val |= BIT7;	/* 100, txclk = DPLL Input */
4322 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4323 		val |= BIT5;	/* 001, txclk = RXC Input */
4324 
4325 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4326 		val |= BIT3;	/* 010, rxclk = BRG */
4327 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4328 		val |= BIT4;	/* 100, rxclk = DPLL */
4329 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4330 		val |= BIT2;	/* 001, rxclk = TXC Input */
4331 
4332 	if (info->params.clock_speed)
4333 		val |= BIT1 + BIT0;
4334 
4335 	wr_reg8(info, CCR, (unsigned char)val);
4336 
4337 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4338 	{
4339 		// program DPLL mode
4340 		switch(info->params.encoding)
4341 		{
4342 		case HDLC_ENCODING_BIPHASE_MARK:
4343 		case HDLC_ENCODING_BIPHASE_SPACE:
4344 			val = BIT7; break;
4345 		case HDLC_ENCODING_BIPHASE_LEVEL:
4346 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4347 			val = BIT7 + BIT6; break;
4348 		default: val = BIT6;	// NRZ encodings
4349 		}
4350 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4351 
4352 		// DPLL requires a 16X reference clock from BRG
4353 		set_rate(info, info->params.clock_speed * 16);
4354 	}
4355 	else
4356 		set_rate(info, info->params.clock_speed);
4357 
4358 	tx_set_idle(info);
4359 
4360 	msc_set_vcr(info);
4361 
4362 	/* SCR (serial control)
4363 	 *
4364 	 * 15  1=tx req on FIFO half empty
4365 	 * 14  1=rx req on FIFO half full
4366 	 * 13  tx data  IRQ enable
4367 	 * 12  tx idle  IRQ enable
4368 	 * 11  underrun IRQ enable
4369 	 * 10  rx data  IRQ enable
4370 	 * 09  rx idle  IRQ enable
4371 	 * 08  overrun  IRQ enable
4372 	 * 07  DSR      IRQ enable
4373 	 * 06  CTS      IRQ enable
4374 	 * 05  DCD      IRQ enable
4375 	 * 04  RI       IRQ enable
4376 	 * 03  reserved, must be zero
4377 	 * 02  1=txd->rxd internal loopback enable
4378 	 * 01  reserved, must be zero
4379 	 * 00  1=master IRQ enable
4380 	 */
4381 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4382 
4383 	if (info->params.loopback)
4384 		enable_loopback(info);
4385 }
4386 
4387 /*
4388  *  set transmit idle mode
4389  */
4390 static void tx_set_idle(struct slgt_info *info)
4391 {
4392 	unsigned char val;
4393 	unsigned short tcr;
4394 
4395 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4396 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4397 	 */
4398 	tcr = rd_reg16(info, TCR);
4399 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4400 		/* disable preamble, set idle size to 16 bits */
4401 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4402 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4403 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4404 	} else if (!(tcr & BIT6)) {
4405 		/* preamble is disabled, set idle size to 8 bits */
4406 		tcr &= ~(BIT5 + BIT4);
4407 	}
4408 	wr_reg16(info, TCR, tcr);
4409 
4410 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4411 		/* LSB of custom tx idle specified in tx idle register */
4412 		val = (unsigned char)(info->idle_mode & 0xff);
4413 	} else {
4414 		/* standard 8 bit idle patterns */
4415 		switch(info->idle_mode)
4416 		{
4417 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4418 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4419 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4420 		case HDLC_TXIDLE_ZEROS:
4421 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4422 		default:                         val = 0xff;
4423 		}
4424 	}
4425 
4426 	wr_reg8(info, TIR, val);
4427 }
4428 
4429 /*
4430  * get state of V24 status (input) signals
4431  */
4432 static void get_gtsignals(struct slgt_info *info)
4433 {
4434 	unsigned short status = rd_reg16(info, SSR);
4435 
4436 	/* clear all serial signals except RTS and DTR */
4437 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4438 
4439 	if (status & BIT3)
4440 		info->signals |= SerialSignal_DSR;
4441 	if (status & BIT2)
4442 		info->signals |= SerialSignal_CTS;
4443 	if (status & BIT1)
4444 		info->signals |= SerialSignal_DCD;
4445 	if (status & BIT0)
4446 		info->signals |= SerialSignal_RI;
4447 }
4448 
4449 /*
4450  * set V.24 Control Register based on current configuration
4451  */
4452 static void msc_set_vcr(struct slgt_info *info)
4453 {
4454 	unsigned char val = 0;
4455 
4456 	/* VCR (V.24 control)
4457 	 *
4458 	 * 07..04  serial IF select
4459 	 * 03      DTR
4460 	 * 02      RTS
4461 	 * 01      LL
4462 	 * 00      RL
4463 	 */
4464 
4465 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4466 	{
4467 	case MGSL_INTERFACE_RS232:
4468 		val |= BIT5; /* 0010 */
4469 		break;
4470 	case MGSL_INTERFACE_V35:
4471 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4472 		break;
4473 	case MGSL_INTERFACE_RS422:
4474 		val |= BIT6; /* 0100 */
4475 		break;
4476 	}
4477 
4478 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4479 		val |= BIT4;
4480 	if (info->signals & SerialSignal_DTR)
4481 		val |= BIT3;
4482 	if (info->signals & SerialSignal_RTS)
4483 		val |= BIT2;
4484 	if (info->if_mode & MGSL_INTERFACE_LL)
4485 		val |= BIT1;
4486 	if (info->if_mode & MGSL_INTERFACE_RL)
4487 		val |= BIT0;
4488 	wr_reg8(info, VCR, val);
4489 }
4490 
4491 /*
4492  * set state of V24 control (output) signals
4493  */
4494 static void set_gtsignals(struct slgt_info *info)
4495 {
4496 	unsigned char val = rd_reg8(info, VCR);
4497 	if (info->signals & SerialSignal_DTR)
4498 		val |= BIT3;
4499 	else
4500 		val &= ~BIT3;
4501 	if (info->signals & SerialSignal_RTS)
4502 		val |= BIT2;
4503 	else
4504 		val &= ~BIT2;
4505 	wr_reg8(info, VCR, val);
4506 }
4507 
4508 /*
4509  * free range of receive DMA buffers (i to last)
4510  */
4511 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4512 {
4513 	int done = 0;
4514 
4515 	while(!done) {
4516 		/* reset current buffer for reuse */
4517 		info->rbufs[i].status = 0;
4518 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4519 		if (i == last)
4520 			done = 1;
4521 		if (++i == info->rbuf_count)
4522 			i = 0;
4523 	}
4524 	info->rbuf_current = i;
4525 }
4526 
4527 /*
4528  * mark all receive DMA buffers as free
4529  */
4530 static void reset_rbufs(struct slgt_info *info)
4531 {
4532 	free_rbufs(info, 0, info->rbuf_count - 1);
4533 	info->rbuf_fill_index = 0;
4534 	info->rbuf_fill_count = 0;
4535 }
4536 
4537 /*
4538  * pass receive HDLC frame to upper layer
4539  *
4540  * return true if frame available, otherwise false
4541  */
4542 static bool rx_get_frame(struct slgt_info *info)
4543 {
4544 	unsigned int start, end;
4545 	unsigned short status;
4546 	unsigned int framesize = 0;
4547 	unsigned long flags;
4548 	struct tty_struct *tty = info->port.tty;
4549 	unsigned char addr_field = 0xff;
4550 	unsigned int crc_size = 0;
4551 
4552 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4553 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4554 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4555 	}
4556 
4557 check_again:
4558 
4559 	framesize = 0;
4560 	addr_field = 0xff;
4561 	start = end = info->rbuf_current;
4562 
4563 	for (;;) {
4564 		if (!desc_complete(info->rbufs[end]))
4565 			goto cleanup;
4566 
4567 		if (framesize == 0 && info->params.addr_filter != 0xff)
4568 			addr_field = info->rbufs[end].buf[0];
4569 
4570 		framesize += desc_count(info->rbufs[end]);
4571 
4572 		if (desc_eof(info->rbufs[end]))
4573 			break;
4574 
4575 		if (++end == info->rbuf_count)
4576 			end = 0;
4577 
4578 		if (end == info->rbuf_current) {
4579 			if (info->rx_enabled){
4580 				spin_lock_irqsave(&info->lock,flags);
4581 				rx_start(info);
4582 				spin_unlock_irqrestore(&info->lock,flags);
4583 			}
4584 			goto cleanup;
4585 		}
4586 	}
4587 
4588 	/* status
4589 	 *
4590 	 * 15      buffer complete
4591 	 * 14..06  reserved
4592 	 * 05..04  residue
4593 	 * 02      eof (end of frame)
4594 	 * 01      CRC error
4595 	 * 00      abort
4596 	 */
4597 	status = desc_status(info->rbufs[end]);
4598 
4599 	/* ignore CRC bit if not using CRC (bit is undefined) */
4600 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4601 		status &= ~BIT1;
4602 
4603 	if (framesize == 0 ||
4604 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4605 		free_rbufs(info, start, end);
4606 		goto check_again;
4607 	}
4608 
4609 	if (framesize < (2 + crc_size) || status & BIT0) {
4610 		info->icount.rxshort++;
4611 		framesize = 0;
4612 	} else if (status & BIT1) {
4613 		info->icount.rxcrc++;
4614 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4615 			framesize = 0;
4616 	}
4617 
4618 #if SYNCLINK_GENERIC_HDLC
4619 	if (framesize == 0) {
4620 		info->netdev->stats.rx_errors++;
4621 		info->netdev->stats.rx_frame_errors++;
4622 	}
4623 #endif
4624 
4625 	DBGBH(("%s rx frame status=%04X size=%d\n",
4626 		info->device_name, status, framesize));
4627 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4628 
4629 	if (framesize) {
4630 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4631 			framesize -= crc_size;
4632 			crc_size = 0;
4633 		}
4634 
4635 		if (framesize > info->max_frame_size + crc_size)
4636 			info->icount.rxlong++;
4637 		else {
4638 			/* copy dma buffer(s) to contiguous temp buffer */
4639 			int copy_count = framesize;
4640 			int i = start;
4641 			unsigned char *p = info->tmp_rbuf;
4642 			info->tmp_rbuf_count = framesize;
4643 
4644 			info->icount.rxok++;
4645 
4646 			while(copy_count) {
4647 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4648 				memcpy(p, info->rbufs[i].buf, partial_count);
4649 				p += partial_count;
4650 				copy_count -= partial_count;
4651 				if (++i == info->rbuf_count)
4652 					i = 0;
4653 			}
4654 
4655 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4656 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4657 				framesize++;
4658 			}
4659 
4660 #if SYNCLINK_GENERIC_HDLC
4661 			if (info->netcount)
4662 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4663 			else
4664 #endif
4665 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4666 		}
4667 	}
4668 	free_rbufs(info, start, end);
4669 	return true;
4670 
4671 cleanup:
4672 	return false;
4673 }
4674 
4675 /*
4676  * pass receive buffer (RAW synchronous mode) to tty layer
4677  * return true if buffer available, otherwise false
4678  */
4679 static bool rx_get_buf(struct slgt_info *info)
4680 {
4681 	unsigned int i = info->rbuf_current;
4682 	unsigned int count;
4683 
4684 	if (!desc_complete(info->rbufs[i]))
4685 		return false;
4686 	count = desc_count(info->rbufs[i]);
4687 	switch(info->params.mode) {
4688 	case MGSL_MODE_MONOSYNC:
4689 	case MGSL_MODE_BISYNC:
4690 	case MGSL_MODE_XSYNC:
4691 		/* ignore residue in byte synchronous modes */
4692 		if (desc_residue(info->rbufs[i]))
4693 			count--;
4694 		break;
4695 	}
4696 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4697 	DBGINFO(("rx_get_buf size=%d\n", count));
4698 	if (count)
4699 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4700 				  info->flag_buf, count);
4701 	free_rbufs(info, i, i);
4702 	return true;
4703 }
4704 
4705 static void reset_tbufs(struct slgt_info *info)
4706 {
4707 	unsigned int i;
4708 	info->tbuf_current = 0;
4709 	for (i=0 ; i < info->tbuf_count ; i++) {
4710 		info->tbufs[i].status = 0;
4711 		info->tbufs[i].count  = 0;
4712 	}
4713 }
4714 
4715 /*
4716  * return number of free transmit DMA buffers
4717  */
4718 static unsigned int free_tbuf_count(struct slgt_info *info)
4719 {
4720 	unsigned int count = 0;
4721 	unsigned int i = info->tbuf_current;
4722 
4723 	do
4724 	{
4725 		if (desc_count(info->tbufs[i]))
4726 			break; /* buffer in use */
4727 		++count;
4728 		if (++i == info->tbuf_count)
4729 			i=0;
4730 	} while (i != info->tbuf_current);
4731 
4732 	/* if tx DMA active, last zero count buffer is in use */
4733 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4734 		--count;
4735 
4736 	return count;
4737 }
4738 
4739 /*
4740  * return number of bytes in unsent transmit DMA buffers
4741  * and the serial controller tx FIFO
4742  */
4743 static unsigned int tbuf_bytes(struct slgt_info *info)
4744 {
4745 	unsigned int total_count = 0;
4746 	unsigned int i = info->tbuf_current;
4747 	unsigned int reg_value;
4748 	unsigned int count;
4749 	unsigned int active_buf_count = 0;
4750 
4751 	/*
4752 	 * Add descriptor counts for all tx DMA buffers.
4753 	 * If count is zero (cleared by DMA controller after read),
4754 	 * the buffer is complete or is actively being read from.
4755 	 *
4756 	 * Record buf_count of last buffer with zero count starting
4757 	 * from current ring position. buf_count is mirror
4758 	 * copy of count and is not cleared by serial controller.
4759 	 * If DMA controller is active, that buffer is actively
4760 	 * being read so add to total.
4761 	 */
4762 	do {
4763 		count = desc_count(info->tbufs[i]);
4764 		if (count)
4765 			total_count += count;
4766 		else if (!total_count)
4767 			active_buf_count = info->tbufs[i].buf_count;
4768 		if (++i == info->tbuf_count)
4769 			i = 0;
4770 	} while (i != info->tbuf_current);
4771 
4772 	/* read tx DMA status register */
4773 	reg_value = rd_reg32(info, TDCSR);
4774 
4775 	/* if tx DMA active, last zero count buffer is in use */
4776 	if (reg_value & BIT0)
4777 		total_count += active_buf_count;
4778 
4779 	/* add tx FIFO count = reg_value[15..8] */
4780 	total_count += (reg_value >> 8) & 0xff;
4781 
4782 	/* if transmitter active add one byte for shift register */
4783 	if (info->tx_active)
4784 		total_count++;
4785 
4786 	return total_count;
4787 }
4788 
4789 /*
4790  * load data into transmit DMA buffer ring and start transmitter if needed
4791  * return true if data accepted, otherwise false (buffers full)
4792  */
4793 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4794 {
4795 	unsigned short count;
4796 	unsigned int i;
4797 	struct slgt_desc *d;
4798 
4799 	/* check required buffer space */
4800 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4801 		return false;
4802 
4803 	DBGDATA(info, buf, size, "tx");
4804 
4805 	/*
4806 	 * copy data to one or more DMA buffers in circular ring
4807 	 * tbuf_start   = first buffer for this data
4808 	 * tbuf_current = next free buffer
4809 	 *
4810 	 * Copy all data before making data visible to DMA controller by
4811 	 * setting descriptor count of the first buffer.
4812 	 * This prevents an active DMA controller from reading the first DMA
4813 	 * buffers of a frame and stopping before the final buffers are filled.
4814 	 */
4815 
4816 	info->tbuf_start = i = info->tbuf_current;
4817 
4818 	while (size) {
4819 		d = &info->tbufs[i];
4820 
4821 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4822 		memcpy(d->buf, buf, count);
4823 
4824 		size -= count;
4825 		buf  += count;
4826 
4827 		/*
4828 		 * set EOF bit for last buffer of HDLC frame or
4829 		 * for every buffer in raw mode
4830 		 */
4831 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4832 		    info->params.mode == MGSL_MODE_RAW)
4833 			set_desc_eof(*d, 1);
4834 		else
4835 			set_desc_eof(*d, 0);
4836 
4837 		/* set descriptor count for all but first buffer */
4838 		if (i != info->tbuf_start)
4839 			set_desc_count(*d, count);
4840 		d->buf_count = count;
4841 
4842 		if (++i == info->tbuf_count)
4843 			i = 0;
4844 	}
4845 
4846 	info->tbuf_current = i;
4847 
4848 	/* set first buffer count to make new data visible to DMA controller */
4849 	d = &info->tbufs[info->tbuf_start];
4850 	set_desc_count(*d, d->buf_count);
4851 
4852 	/* start transmitter if needed and update transmit timeout */
4853 	if (!info->tx_active)
4854 		tx_start(info);
4855 	update_tx_timer(info);
4856 
4857 	return true;
4858 }
4859 
4860 static int register_test(struct slgt_info *info)
4861 {
4862 	static unsigned short patterns[] =
4863 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4864 	static unsigned int count = ARRAY_SIZE(patterns);
4865 	unsigned int i;
4866 	int rc = 0;
4867 
4868 	for (i=0 ; i < count ; i++) {
4869 		wr_reg16(info, TIR, patterns[i]);
4870 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4871 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4872 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4873 			rc = -ENODEV;
4874 			break;
4875 		}
4876 	}
4877 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4878 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4879 	return rc;
4880 }
4881 
4882 static int irq_test(struct slgt_info *info)
4883 {
4884 	unsigned long timeout;
4885 	unsigned long flags;
4886 	struct tty_struct *oldtty = info->port.tty;
4887 	u32 speed = info->params.data_rate;
4888 
4889 	info->params.data_rate = 921600;
4890 	info->port.tty = NULL;
4891 
4892 	spin_lock_irqsave(&info->lock, flags);
4893 	async_mode(info);
4894 	slgt_irq_on(info, IRQ_TXIDLE);
4895 
4896 	/* enable transmitter */
4897 	wr_reg16(info, TCR,
4898 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4899 
4900 	/* write one byte and wait for tx idle */
4901 	wr_reg16(info, TDR, 0);
4902 
4903 	/* assume failure */
4904 	info->init_error = DiagStatus_IrqFailure;
4905 	info->irq_occurred = false;
4906 
4907 	spin_unlock_irqrestore(&info->lock, flags);
4908 
4909 	timeout=100;
4910 	while(timeout-- && !info->irq_occurred)
4911 		msleep_interruptible(10);
4912 
4913 	spin_lock_irqsave(&info->lock,flags);
4914 	reset_port(info);
4915 	spin_unlock_irqrestore(&info->lock,flags);
4916 
4917 	info->params.data_rate = speed;
4918 	info->port.tty = oldtty;
4919 
4920 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4921 	return info->irq_occurred ? 0 : -ENODEV;
4922 }
4923 
4924 static int loopback_test_rx(struct slgt_info *info)
4925 {
4926 	unsigned char *src, *dest;
4927 	int count;
4928 
4929 	if (desc_complete(info->rbufs[0])) {
4930 		count = desc_count(info->rbufs[0]);
4931 		src   = info->rbufs[0].buf;
4932 		dest  = info->tmp_rbuf;
4933 
4934 		for( ; count ; count-=2, src+=2) {
4935 			/* src=data byte (src+1)=status byte */
4936 			if (!(*(src+1) & (BIT9 + BIT8))) {
4937 				*dest = *src;
4938 				dest++;
4939 				info->tmp_rbuf_count++;
4940 			}
4941 		}
4942 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4943 		return 1;
4944 	}
4945 	return 0;
4946 }
4947 
4948 static int loopback_test(struct slgt_info *info)
4949 {
4950 #define TESTFRAMESIZE 20
4951 
4952 	unsigned long timeout;
4953 	u16 count;
4954 	unsigned char buf[TESTFRAMESIZE];
4955 	int rc = -ENODEV;
4956 	unsigned long flags;
4957 
4958 	struct tty_struct *oldtty = info->port.tty;
4959 	MGSL_PARAMS params;
4960 
4961 	memcpy(&params, &info->params, sizeof(params));
4962 
4963 	info->params.mode = MGSL_MODE_ASYNC;
4964 	info->params.data_rate = 921600;
4965 	info->params.loopback = 1;
4966 	info->port.tty = NULL;
4967 
4968 	/* build and send transmit frame */
4969 	for (count = 0; count < TESTFRAMESIZE; ++count)
4970 		buf[count] = (unsigned char)count;
4971 
4972 	info->tmp_rbuf_count = 0;
4973 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4974 
4975 	/* program hardware for HDLC and enabled receiver */
4976 	spin_lock_irqsave(&info->lock,flags);
4977 	async_mode(info);
4978 	rx_start(info);
4979 	tx_load(info, buf, count);
4980 	spin_unlock_irqrestore(&info->lock, flags);
4981 
4982 	/* wait for receive complete */
4983 	for (timeout = 100; timeout; --timeout) {
4984 		msleep_interruptible(10);
4985 		if (loopback_test_rx(info)) {
4986 			rc = 0;
4987 			break;
4988 		}
4989 	}
4990 
4991 	/* verify received frame length and contents */
4992 	if (!rc && (info->tmp_rbuf_count != count ||
4993 		  memcmp(buf, info->tmp_rbuf, count))) {
4994 		rc = -ENODEV;
4995 	}
4996 
4997 	spin_lock_irqsave(&info->lock,flags);
4998 	reset_adapter(info);
4999 	spin_unlock_irqrestore(&info->lock,flags);
5000 
5001 	memcpy(&info->params, &params, sizeof(info->params));
5002 	info->port.tty = oldtty;
5003 
5004 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5005 	return rc;
5006 }
5007 
5008 static int adapter_test(struct slgt_info *info)
5009 {
5010 	DBGINFO(("testing %s\n", info->device_name));
5011 	if (register_test(info) < 0) {
5012 		printk("register test failure %s addr=%08X\n",
5013 			info->device_name, info->phys_reg_addr);
5014 	} else if (irq_test(info) < 0) {
5015 		printk("IRQ test failure %s IRQ=%d\n",
5016 			info->device_name, info->irq_level);
5017 	} else if (loopback_test(info) < 0) {
5018 		printk("loopback test failure %s\n", info->device_name);
5019 	}
5020 	return info->init_error;
5021 }
5022 
5023 /*
5024  * transmit timeout handler
5025  */
5026 static void tx_timeout(struct timer_list *t)
5027 {
5028 	struct slgt_info *info = from_timer(info, t, tx_timer);
5029 	unsigned long flags;
5030 
5031 	DBGINFO(("%s tx_timeout\n", info->device_name));
5032 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5033 		info->icount.txtimeout++;
5034 	}
5035 	spin_lock_irqsave(&info->lock,flags);
5036 	tx_stop(info);
5037 	spin_unlock_irqrestore(&info->lock,flags);
5038 
5039 #if SYNCLINK_GENERIC_HDLC
5040 	if (info->netcount)
5041 		hdlcdev_tx_done(info);
5042 	else
5043 #endif
5044 		bh_transmit(info);
5045 }
5046 
5047 /*
5048  * receive buffer polling timer
5049  */
5050 static void rx_timeout(struct timer_list *t)
5051 {
5052 	struct slgt_info *info = from_timer(info, t, rx_timer);
5053 	unsigned long flags;
5054 
5055 	DBGINFO(("%s rx_timeout\n", info->device_name));
5056 	spin_lock_irqsave(&info->lock, flags);
5057 	info->pending_bh |= BH_RECEIVE;
5058 	spin_unlock_irqrestore(&info->lock, flags);
5059 	bh_handler(&info->task);
5060 }
5061 
5062