xref: /openbmc/linux/drivers/tty/synclink_gt.c (revision e73ad388)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22 
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36 
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44 
45 
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74 
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80 
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86 
87 /*
88  * module identification
89  */
90 static char *driver_name     = "SyncLink GT";
91 static char *slgt_driver_name = "synclink_gt";
92 static char *tty_dev_prefix  = "ttySLG";
93 MODULE_LICENSE("GPL");
94 #define MGSL_MAGIC 0x5401
95 #define MAX_DEVICES 32
96 
97 static const struct pci_device_id pci_table[] = {
98 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
102 	{0,}, /* terminate list */
103 };
104 MODULE_DEVICE_TABLE(pci, pci_table);
105 
106 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
107 static void remove_one(struct pci_dev *dev);
108 static struct pci_driver pci_driver = {
109 	.name		= "synclink_gt",
110 	.id_table	= pci_table,
111 	.probe		= init_one,
112 	.remove		= remove_one,
113 };
114 
115 static bool pci_registered;
116 
117 /*
118  * module configuration and status
119  */
120 static struct slgt_info *slgt_device_list;
121 static int slgt_device_count;
122 
123 static int ttymajor;
124 static int debug_level;
125 static int maxframe[MAX_DEVICES];
126 
127 module_param(ttymajor, int, 0);
128 module_param(debug_level, int, 0);
129 module_param_array(maxframe, int, NULL, 0);
130 
131 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
132 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
133 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
134 
135 /*
136  * tty support and callbacks
137  */
138 static struct tty_driver *serial_driver;
139 
140 static void wait_until_sent(struct tty_struct *tty, int timeout);
141 static void flush_buffer(struct tty_struct *tty);
142 static void tx_release(struct tty_struct *tty);
143 
144 /*
145  * generic HDLC support
146  */
147 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
148 
149 
150 /*
151  * device specific structures, macros and functions
152  */
153 
154 #define SLGT_MAX_PORTS 4
155 #define SLGT_REG_SIZE  256
156 
157 /*
158  * conditional wait facility
159  */
160 struct cond_wait {
161 	struct cond_wait *next;
162 	wait_queue_head_t q;
163 	wait_queue_entry_t wait;
164 	unsigned int data;
165 };
166 static void flush_cond_wait(struct cond_wait **head);
167 
168 /*
169  * DMA buffer descriptor and access macros
170  */
171 struct slgt_desc
172 {
173 	__le16 count;
174 	__le16 status;
175 	__le32 pbuf;  /* physical address of data buffer */
176 	__le32 next;  /* physical address of next descriptor */
177 
178 	/* driver book keeping */
179 	char *buf;          /* virtual  address of data buffer */
180     	unsigned int pdesc; /* physical address of this descriptor */
181 	dma_addr_t buf_dma_addr;
182 	unsigned short buf_count;
183 };
184 
185 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
186 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
187 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
188 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
189 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
190 #define desc_count(a)      (le16_to_cpu((a).count))
191 #define desc_status(a)     (le16_to_cpu((a).status))
192 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
193 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
194 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
195 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
196 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
197 
198 struct _input_signal_events {
199 	int ri_up;
200 	int ri_down;
201 	int dsr_up;
202 	int dsr_down;
203 	int dcd_up;
204 	int dcd_down;
205 	int cts_up;
206 	int cts_down;
207 };
208 
209 /*
210  * device instance data structure
211  */
212 struct slgt_info {
213 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
214 	struct tty_port port;
215 
216 	struct slgt_info *next_device;	/* device list link */
217 
218 	int magic;
219 
220 	char device_name[25];
221 	struct pci_dev *pdev;
222 
223 	int port_count;  /* count of ports on adapter */
224 	int adapter_num; /* adapter instance number */
225 	int port_num;    /* port instance number */
226 
227 	/* array of pointers to port contexts on this adapter */
228 	struct slgt_info *port_array[SLGT_MAX_PORTS];
229 
230 	int			line;		/* tty line instance number */
231 
232 	struct mgsl_icount	icount;
233 
234 	int			timeout;
235 	int			x_char;		/* xon/xoff character */
236 	unsigned int		read_status_mask;
237 	unsigned int 		ignore_status_mask;
238 
239 	wait_queue_head_t	status_event_wait_q;
240 	wait_queue_head_t	event_wait_q;
241 	struct timer_list	tx_timer;
242 	struct timer_list	rx_timer;
243 
244 	unsigned int            gpio_present;
245 	struct cond_wait        *gpio_wait_q;
246 
247 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
248 
249 	struct work_struct task;
250 	u32 pending_bh;
251 	bool bh_requested;
252 	bool bh_running;
253 
254 	int isr_overflow;
255 	bool irq_requested;	/* true if IRQ requested */
256 	bool irq_occurred;	/* for diagnostics use */
257 
258 	/* device configuration */
259 
260 	unsigned int bus_type;
261 	unsigned int irq_level;
262 	unsigned long irq_flags;
263 
264 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
265 	u32 phys_reg_addr;
266 	bool reg_addr_requested;
267 
268 	MGSL_PARAMS params;       /* communications parameters */
269 	u32 idle_mode;
270 	u32 max_frame_size;       /* as set by device config */
271 
272 	unsigned int rbuf_fill_level;
273 	unsigned int rx_pio;
274 	unsigned int if_mode;
275 	unsigned int base_clock;
276 	unsigned int xsync;
277 	unsigned int xctrl;
278 
279 	/* device status */
280 
281 	bool rx_enabled;
282 	bool rx_restart;
283 
284 	bool tx_enabled;
285 	bool tx_active;
286 
287 	unsigned char signals;    /* serial signal states */
288 	int init_error;  /* initialization error */
289 
290 	unsigned char *tx_buf;
291 	int tx_count;
292 
293 	char *flag_buf;
294 	bool drop_rts_on_tx_done;
295 	struct	_input_signal_events	input_signal_events;
296 
297 	int dcd_chkcount;	/* check counts to prevent */
298 	int cts_chkcount;	/* too many IRQs if a signal */
299 	int dsr_chkcount;	/* is floating */
300 	int ri_chkcount;
301 
302 	char *bufs;		/* virtual address of DMA buffer lists */
303 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
304 
305 	unsigned int rbuf_count;
306 	struct slgt_desc *rbufs;
307 	unsigned int rbuf_current;
308 	unsigned int rbuf_index;
309 	unsigned int rbuf_fill_index;
310 	unsigned short rbuf_fill_count;
311 
312 	unsigned int tbuf_count;
313 	struct slgt_desc *tbufs;
314 	unsigned int tbuf_current;
315 	unsigned int tbuf_start;
316 
317 	unsigned char *tmp_rbuf;
318 	unsigned int tmp_rbuf_count;
319 
320 	/* SPPP/Cisco HDLC device parts */
321 
322 	int netcount;
323 	spinlock_t netlock;
324 #if SYNCLINK_GENERIC_HDLC
325 	struct net_device *netdev;
326 #endif
327 
328 };
329 
330 static MGSL_PARAMS default_params = {
331 	.mode            = MGSL_MODE_HDLC,
332 	.loopback        = 0,
333 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
334 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
335 	.clock_speed     = 0,
336 	.addr_filter     = 0xff,
337 	.crc_type        = HDLC_CRC_16_CCITT,
338 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
339 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
340 	.data_rate       = 9600,
341 	.data_bits       = 8,
342 	.stop_bits       = 1,
343 	.parity          = ASYNC_PARITY_NONE
344 };
345 
346 
347 #define BH_RECEIVE  1
348 #define BH_TRANSMIT 2
349 #define BH_STATUS   4
350 #define IO_PIN_SHUTDOWN_LIMIT 100
351 
352 #define DMABUFSIZE 256
353 #define DESC_LIST_SIZE 4096
354 
355 #define MASK_PARITY  BIT1
356 #define MASK_FRAMING BIT0
357 #define MASK_BREAK   BIT14
358 #define MASK_OVERRUN BIT4
359 
360 #define GSR   0x00 /* global status */
361 #define JCR   0x04 /* JTAG control */
362 #define IODR  0x08 /* GPIO direction */
363 #define IOER  0x0c /* GPIO interrupt enable */
364 #define IOVR  0x10 /* GPIO value */
365 #define IOSR  0x14 /* GPIO interrupt status */
366 #define TDR   0x80 /* tx data */
367 #define RDR   0x80 /* rx data */
368 #define TCR   0x82 /* tx control */
369 #define TIR   0x84 /* tx idle */
370 #define TPR   0x85 /* tx preamble */
371 #define RCR   0x86 /* rx control */
372 #define VCR   0x88 /* V.24 control */
373 #define CCR   0x89 /* clock control */
374 #define BDR   0x8a /* baud divisor */
375 #define SCR   0x8c /* serial control */
376 #define SSR   0x8e /* serial status */
377 #define RDCSR 0x90 /* rx DMA control/status */
378 #define TDCSR 0x94 /* tx DMA control/status */
379 #define RDDAR 0x98 /* rx DMA descriptor address */
380 #define TDDAR 0x9c /* tx DMA descriptor address */
381 #define XSR   0x40 /* extended sync pattern */
382 #define XCR   0x44 /* extended control */
383 
384 #define RXIDLE      BIT14
385 #define RXBREAK     BIT14
386 #define IRQ_TXDATA  BIT13
387 #define IRQ_TXIDLE  BIT12
388 #define IRQ_TXUNDER BIT11 /* HDLC */
389 #define IRQ_RXDATA  BIT10
390 #define IRQ_RXIDLE  BIT9  /* HDLC */
391 #define IRQ_RXBREAK BIT9  /* async */
392 #define IRQ_RXOVER  BIT8
393 #define IRQ_DSR     BIT7
394 #define IRQ_CTS     BIT6
395 #define IRQ_DCD     BIT5
396 #define IRQ_RI      BIT4
397 #define IRQ_ALL     0x3ff0
398 #define IRQ_MASTER  BIT0
399 
400 #define slgt_irq_on(info, mask) \
401 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
402 #define slgt_irq_off(info, mask) \
403 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
404 
405 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
406 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
407 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
408 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
409 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
410 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
411 
412 static void  msc_set_vcr(struct slgt_info *info);
413 
414 static int  startup(struct slgt_info *info);
415 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
416 static void shutdown(struct slgt_info *info);
417 static void program_hw(struct slgt_info *info);
418 static void change_params(struct slgt_info *info);
419 
420 static int  adapter_test(struct slgt_info *info);
421 
422 static void reset_port(struct slgt_info *info);
423 static void async_mode(struct slgt_info *info);
424 static void sync_mode(struct slgt_info *info);
425 
426 static void rx_stop(struct slgt_info *info);
427 static void rx_start(struct slgt_info *info);
428 static void reset_rbufs(struct slgt_info *info);
429 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
430 static bool rx_get_frame(struct slgt_info *info);
431 static bool rx_get_buf(struct slgt_info *info);
432 
433 static void tx_start(struct slgt_info *info);
434 static void tx_stop(struct slgt_info *info);
435 static void tx_set_idle(struct slgt_info *info);
436 static unsigned int tbuf_bytes(struct slgt_info *info);
437 static void reset_tbufs(struct slgt_info *info);
438 static void tdma_reset(struct slgt_info *info);
439 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
440 
441 static void get_signals(struct slgt_info *info);
442 static void set_signals(struct slgt_info *info);
443 static void set_rate(struct slgt_info *info, u32 data_rate);
444 
445 static void bh_transmit(struct slgt_info *info);
446 static void isr_txeom(struct slgt_info *info, unsigned short status);
447 
448 static void tx_timeout(struct timer_list *t);
449 static void rx_timeout(struct timer_list *t);
450 
451 /*
452  * ioctl handlers
453  */
454 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
455 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
456 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
457 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
458 static int  set_txidle(struct slgt_info *info, int idle_mode);
459 static int  tx_enable(struct slgt_info *info, int enable);
460 static int  tx_abort(struct slgt_info *info);
461 static int  rx_enable(struct slgt_info *info, int enable);
462 static int  modem_input_wait(struct slgt_info *info,int arg);
463 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
464 static int  get_interface(struct slgt_info *info, int __user *if_mode);
465 static int  set_interface(struct slgt_info *info, int if_mode);
466 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
467 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
468 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
469 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
470 static int  set_xsync(struct slgt_info *info, int if_mode);
471 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
472 static int  set_xctrl(struct slgt_info *info, int if_mode);
473 
474 /*
475  * driver functions
476  */
477 static void release_resources(struct slgt_info *info);
478 
479 /*
480  * DEBUG OUTPUT CODE
481  */
482 #ifndef DBGINFO
483 #define DBGINFO(fmt)
484 #endif
485 #ifndef DBGERR
486 #define DBGERR(fmt)
487 #endif
488 #ifndef DBGBH
489 #define DBGBH(fmt)
490 #endif
491 #ifndef DBGISR
492 #define DBGISR(fmt)
493 #endif
494 
495 #ifdef DBGDATA
496 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
497 {
498 	int i;
499 	int linecount;
500 	printk("%s %s data:\n",info->device_name, label);
501 	while(count) {
502 		linecount = (count > 16) ? 16 : count;
503 		for(i=0; i < linecount; i++)
504 			printk("%02X ",(unsigned char)data[i]);
505 		for(;i<17;i++)
506 			printk("   ");
507 		for(i=0;i<linecount;i++) {
508 			if (data[i]>=040 && data[i]<=0176)
509 				printk("%c",data[i]);
510 			else
511 				printk(".");
512 		}
513 		printk("\n");
514 		data  += linecount;
515 		count -= linecount;
516 	}
517 }
518 #else
519 #define DBGDATA(info, buf, size, label)
520 #endif
521 
522 #ifdef DBGTBUF
523 static void dump_tbufs(struct slgt_info *info)
524 {
525 	int i;
526 	printk("tbuf_current=%d\n", info->tbuf_current);
527 	for (i=0 ; i < info->tbuf_count ; i++) {
528 		printk("%d: count=%04X status=%04X\n",
529 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
530 	}
531 }
532 #else
533 #define DBGTBUF(info)
534 #endif
535 
536 #ifdef DBGRBUF
537 static void dump_rbufs(struct slgt_info *info)
538 {
539 	int i;
540 	printk("rbuf_current=%d\n", info->rbuf_current);
541 	for (i=0 ; i < info->rbuf_count ; i++) {
542 		printk("%d: count=%04X status=%04X\n",
543 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
544 	}
545 }
546 #else
547 #define DBGRBUF(info)
548 #endif
549 
550 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
551 {
552 #ifdef SANITY_CHECK
553 	if (!info) {
554 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
555 		return 1;
556 	}
557 	if (info->magic != MGSL_MAGIC) {
558 		printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
559 		return 1;
560 	}
561 #else
562 	if (!info)
563 		return 1;
564 #endif
565 	return 0;
566 }
567 
568 /*
569  * line discipline callback wrappers
570  *
571  * The wrappers maintain line discipline references
572  * while calling into the line discipline.
573  *
574  * ldisc_receive_buf  - pass receive data to line discipline
575  */
576 static void ldisc_receive_buf(struct tty_struct *tty,
577 			      const __u8 *data, char *flags, int count)
578 {
579 	struct tty_ldisc *ld;
580 	if (!tty)
581 		return;
582 	ld = tty_ldisc_ref(tty);
583 	if (ld) {
584 		if (ld->ops->receive_buf)
585 			ld->ops->receive_buf(tty, data, flags, count);
586 		tty_ldisc_deref(ld);
587 	}
588 }
589 
590 /* tty callbacks */
591 
592 static int open(struct tty_struct *tty, struct file *filp)
593 {
594 	struct slgt_info *info;
595 	int retval, line;
596 	unsigned long flags;
597 
598 	line = tty->index;
599 	if (line >= slgt_device_count) {
600 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
601 		return -ENODEV;
602 	}
603 
604 	info = slgt_device_list;
605 	while(info && info->line != line)
606 		info = info->next_device;
607 	if (sanity_check(info, tty->name, "open"))
608 		return -ENODEV;
609 	if (info->init_error) {
610 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
611 		return -ENODEV;
612 	}
613 
614 	tty->driver_data = info;
615 	info->port.tty = tty;
616 
617 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
618 
619 	mutex_lock(&info->port.mutex);
620 
621 	spin_lock_irqsave(&info->netlock, flags);
622 	if (info->netcount) {
623 		retval = -EBUSY;
624 		spin_unlock_irqrestore(&info->netlock, flags);
625 		mutex_unlock(&info->port.mutex);
626 		goto cleanup;
627 	}
628 	info->port.count++;
629 	spin_unlock_irqrestore(&info->netlock, flags);
630 
631 	if (info->port.count == 1) {
632 		/* 1st open on this device, init hardware */
633 		retval = startup(info);
634 		if (retval < 0) {
635 			mutex_unlock(&info->port.mutex);
636 			goto cleanup;
637 		}
638 	}
639 	mutex_unlock(&info->port.mutex);
640 	retval = block_til_ready(tty, filp, info);
641 	if (retval) {
642 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
643 		goto cleanup;
644 	}
645 
646 	retval = 0;
647 
648 cleanup:
649 	if (retval) {
650 		if (tty->count == 1)
651 			info->port.tty = NULL; /* tty layer will release tty struct */
652 		if(info->port.count)
653 			info->port.count--;
654 	}
655 
656 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
657 	return retval;
658 }
659 
660 static void close(struct tty_struct *tty, struct file *filp)
661 {
662 	struct slgt_info *info = tty->driver_data;
663 
664 	if (sanity_check(info, tty->name, "close"))
665 		return;
666 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
667 
668 	if (tty_port_close_start(&info->port, tty, filp) == 0)
669 		goto cleanup;
670 
671 	mutex_lock(&info->port.mutex);
672 	if (tty_port_initialized(&info->port))
673  		wait_until_sent(tty, info->timeout);
674 	flush_buffer(tty);
675 	tty_ldisc_flush(tty);
676 
677 	shutdown(info);
678 	mutex_unlock(&info->port.mutex);
679 
680 	tty_port_close_end(&info->port, tty);
681 	info->port.tty = NULL;
682 cleanup:
683 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
684 }
685 
686 static void hangup(struct tty_struct *tty)
687 {
688 	struct slgt_info *info = tty->driver_data;
689 	unsigned long flags;
690 
691 	if (sanity_check(info, tty->name, "hangup"))
692 		return;
693 	DBGINFO(("%s hangup\n", info->device_name));
694 
695 	flush_buffer(tty);
696 
697 	mutex_lock(&info->port.mutex);
698 	shutdown(info);
699 
700 	spin_lock_irqsave(&info->port.lock, flags);
701 	info->port.count = 0;
702 	info->port.tty = NULL;
703 	spin_unlock_irqrestore(&info->port.lock, flags);
704 	tty_port_set_active(&info->port, 0);
705 	mutex_unlock(&info->port.mutex);
706 
707 	wake_up_interruptible(&info->port.open_wait);
708 }
709 
710 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
711 {
712 	struct slgt_info *info = tty->driver_data;
713 	unsigned long flags;
714 
715 	DBGINFO(("%s set_termios\n", tty->driver->name));
716 
717 	change_params(info);
718 
719 	/* Handle transition to B0 status */
720 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
721 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
722 		spin_lock_irqsave(&info->lock,flags);
723 		set_signals(info);
724 		spin_unlock_irqrestore(&info->lock,flags);
725 	}
726 
727 	/* Handle transition away from B0 status */
728 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
729 		info->signals |= SerialSignal_DTR;
730 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
731 			info->signals |= SerialSignal_RTS;
732 		spin_lock_irqsave(&info->lock,flags);
733 	 	set_signals(info);
734 		spin_unlock_irqrestore(&info->lock,flags);
735 	}
736 
737 	/* Handle turning off CRTSCTS */
738 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
739 		tty->hw_stopped = 0;
740 		tx_release(tty);
741 	}
742 }
743 
744 static void update_tx_timer(struct slgt_info *info)
745 {
746 	/*
747 	 * use worst case speed of 1200bps to calculate transmit timeout
748 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
749 	 */
750 	if (info->params.mode == MGSL_MODE_HDLC) {
751 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
752 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
753 	}
754 }
755 
756 static int write(struct tty_struct *tty,
757 		 const unsigned char *buf, int count)
758 {
759 	int ret = 0;
760 	struct slgt_info *info = tty->driver_data;
761 	unsigned long flags;
762 
763 	if (sanity_check(info, tty->name, "write"))
764 		return -EIO;
765 
766 	DBGINFO(("%s write count=%d\n", info->device_name, count));
767 
768 	if (!info->tx_buf || (count > info->max_frame_size))
769 		return -EIO;
770 
771 	if (!count || tty->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 int write_room(struct tty_struct *tty)
872 {
873 	struct slgt_info *info = tty->driver_data;
874 	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=%d\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->stopped ||
893 	    tty->hw_stopped || !info->tx_buf)
894 		return;
895 
896 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
897 
898 	spin_lock_irqsave(&info->lock,flags);
899 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
900 		info->tx_count = 0;
901 	spin_unlock_irqrestore(&info->lock,flags);
902 }
903 
904 static void flush_buffer(struct tty_struct *tty)
905 {
906 	struct slgt_info *info = tty->driver_data;
907 	unsigned long flags;
908 
909 	if (sanity_check(info, tty->name, "flush_buffer"))
910 		return;
911 	DBGINFO(("%s flush_buffer\n", info->device_name));
912 
913 	spin_lock_irqsave(&info->lock, flags);
914 	info->tx_count = 0;
915 	spin_unlock_irqrestore(&info->lock, flags);
916 
917 	tty_wakeup(tty);
918 }
919 
920 /*
921  * throttle (stop) transmitter
922  */
923 static void tx_hold(struct tty_struct *tty)
924 {
925 	struct slgt_info *info = tty->driver_data;
926 	unsigned long flags;
927 
928 	if (sanity_check(info, tty->name, "tx_hold"))
929 		return;
930 	DBGINFO(("%s tx_hold\n", info->device_name));
931 	spin_lock_irqsave(&info->lock,flags);
932 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
933 	 	tx_stop(info);
934 	spin_unlock_irqrestore(&info->lock,flags);
935 }
936 
937 /*
938  * release (start) transmitter
939  */
940 static void tx_release(struct tty_struct *tty)
941 {
942 	struct slgt_info *info = tty->driver_data;
943 	unsigned long flags;
944 
945 	if (sanity_check(info, tty->name, "tx_release"))
946 		return;
947 	DBGINFO(("%s tx_release\n", info->device_name));
948 	spin_lock_irqsave(&info->lock, flags);
949 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
950 		info->tx_count = 0;
951 	spin_unlock_irqrestore(&info->lock, flags);
952 }
953 
954 /*
955  * Service an IOCTL request
956  *
957  * Arguments
958  *
959  * 	tty	pointer to tty instance data
960  * 	cmd	IOCTL command code
961  * 	arg	command argument/context
962  *
963  * Return 0 if success, otherwise error code
964  */
965 static int ioctl(struct tty_struct *tty,
966 		 unsigned int cmd, unsigned long arg)
967 {
968 	struct slgt_info *info = tty->driver_data;
969 	void __user *argp = (void __user *)arg;
970 	int ret;
971 
972 	if (sanity_check(info, tty->name, "ioctl"))
973 		return -ENODEV;
974 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
975 
976 	if (cmd != TIOCMIWAIT) {
977 		if (tty_io_error(tty))
978 		    return -EIO;
979 	}
980 
981 	switch (cmd) {
982 	case MGSL_IOCWAITEVENT:
983 		return wait_mgsl_event(info, argp);
984 	case TIOCMIWAIT:
985 		return modem_input_wait(info,(int)arg);
986 	case MGSL_IOCSGPIO:
987 		return set_gpio(info, argp);
988 	case MGSL_IOCGGPIO:
989 		return get_gpio(info, argp);
990 	case MGSL_IOCWAITGPIO:
991 		return wait_gpio(info, argp);
992 	case MGSL_IOCGXSYNC:
993 		return get_xsync(info, argp);
994 	case MGSL_IOCSXSYNC:
995 		return set_xsync(info, (int)arg);
996 	case MGSL_IOCGXCTRL:
997 		return get_xctrl(info, argp);
998 	case MGSL_IOCSXCTRL:
999 		return set_xctrl(info, (int)arg);
1000 	}
1001 	mutex_lock(&info->port.mutex);
1002 	switch (cmd) {
1003 	case MGSL_IOCGPARAMS:
1004 		ret = get_params(info, argp);
1005 		break;
1006 	case MGSL_IOCSPARAMS:
1007 		ret = set_params(info, argp);
1008 		break;
1009 	case MGSL_IOCGTXIDLE:
1010 		ret = get_txidle(info, argp);
1011 		break;
1012 	case MGSL_IOCSTXIDLE:
1013 		ret = set_txidle(info, (int)arg);
1014 		break;
1015 	case MGSL_IOCTXENABLE:
1016 		ret = tx_enable(info, (int)arg);
1017 		break;
1018 	case MGSL_IOCRXENABLE:
1019 		ret = rx_enable(info, (int)arg);
1020 		break;
1021 	case MGSL_IOCTXABORT:
1022 		ret = tx_abort(info);
1023 		break;
1024 	case MGSL_IOCGSTATS:
1025 		ret = get_stats(info, argp);
1026 		break;
1027 	case MGSL_IOCGIF:
1028 		ret = get_interface(info, argp);
1029 		break;
1030 	case MGSL_IOCSIF:
1031 		ret = set_interface(info,(int)arg);
1032 		break;
1033 	default:
1034 		ret = -ENOIOCTLCMD;
1035 	}
1036 	mutex_unlock(&info->port.mutex);
1037 	return ret;
1038 }
1039 
1040 static int get_icount(struct tty_struct *tty,
1041 				struct serial_icounter_struct *icount)
1042 
1043 {
1044 	struct slgt_info *info = tty->driver_data;
1045 	struct mgsl_icount cnow;	/* kernel counter temps */
1046 	unsigned long flags;
1047 
1048 	spin_lock_irqsave(&info->lock,flags);
1049 	cnow = info->icount;
1050 	spin_unlock_irqrestore(&info->lock,flags);
1051 
1052 	icount->cts = cnow.cts;
1053 	icount->dsr = cnow.dsr;
1054 	icount->rng = cnow.rng;
1055 	icount->dcd = cnow.dcd;
1056 	icount->rx = cnow.rx;
1057 	icount->tx = cnow.tx;
1058 	icount->frame = cnow.frame;
1059 	icount->overrun = cnow.overrun;
1060 	icount->parity = cnow.parity;
1061 	icount->brk = cnow.brk;
1062 	icount->buf_overrun = cnow.buf_overrun;
1063 
1064 	return 0;
1065 }
1066 
1067 /*
1068  * support for 32 bit ioctl calls on 64 bit systems
1069  */
1070 #ifdef CONFIG_COMPAT
1071 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1072 {
1073 	struct MGSL_PARAMS32 tmp_params;
1074 
1075 	DBGINFO(("%s get_params32\n", info->device_name));
1076 	memset(&tmp_params, 0, sizeof(tmp_params));
1077 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1078 	tmp_params.loopback        = info->params.loopback;
1079 	tmp_params.flags           = info->params.flags;
1080 	tmp_params.encoding        = info->params.encoding;
1081 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1082 	tmp_params.addr_filter     = info->params.addr_filter;
1083 	tmp_params.crc_type        = info->params.crc_type;
1084 	tmp_params.preamble_length = info->params.preamble_length;
1085 	tmp_params.preamble        = info->params.preamble;
1086 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1087 	tmp_params.data_bits       = info->params.data_bits;
1088 	tmp_params.stop_bits       = info->params.stop_bits;
1089 	tmp_params.parity          = info->params.parity;
1090 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1091 		return -EFAULT;
1092 	return 0;
1093 }
1094 
1095 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1096 {
1097 	struct MGSL_PARAMS32 tmp_params;
1098 
1099 	DBGINFO(("%s set_params32\n", info->device_name));
1100 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1101 		return -EFAULT;
1102 
1103 	spin_lock(&info->lock);
1104 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1105 		info->base_clock = tmp_params.clock_speed;
1106 	} else {
1107 		info->params.mode            = tmp_params.mode;
1108 		info->params.loopback        = tmp_params.loopback;
1109 		info->params.flags           = tmp_params.flags;
1110 		info->params.encoding        = tmp_params.encoding;
1111 		info->params.clock_speed     = tmp_params.clock_speed;
1112 		info->params.addr_filter     = tmp_params.addr_filter;
1113 		info->params.crc_type        = tmp_params.crc_type;
1114 		info->params.preamble_length = tmp_params.preamble_length;
1115 		info->params.preamble        = tmp_params.preamble;
1116 		info->params.data_rate       = tmp_params.data_rate;
1117 		info->params.data_bits       = tmp_params.data_bits;
1118 		info->params.stop_bits       = tmp_params.stop_bits;
1119 		info->params.parity          = tmp_params.parity;
1120 	}
1121 	spin_unlock(&info->lock);
1122 
1123 	program_hw(info);
1124 
1125 	return 0;
1126 }
1127 
1128 static long slgt_compat_ioctl(struct tty_struct *tty,
1129 			 unsigned int cmd, unsigned long arg)
1130 {
1131 	struct slgt_info *info = tty->driver_data;
1132 	int rc;
1133 
1134 	if (sanity_check(info, tty->name, "compat_ioctl"))
1135 		return -ENODEV;
1136 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1137 
1138 	switch (cmd) {
1139 	case MGSL_IOCSPARAMS32:
1140 		rc = set_params32(info, compat_ptr(arg));
1141 		break;
1142 
1143 	case MGSL_IOCGPARAMS32:
1144 		rc = get_params32(info, compat_ptr(arg));
1145 		break;
1146 
1147 	case MGSL_IOCGPARAMS:
1148 	case MGSL_IOCSPARAMS:
1149 	case MGSL_IOCGTXIDLE:
1150 	case MGSL_IOCGSTATS:
1151 	case MGSL_IOCWAITEVENT:
1152 	case MGSL_IOCGIF:
1153 	case MGSL_IOCSGPIO:
1154 	case MGSL_IOCGGPIO:
1155 	case MGSL_IOCWAITGPIO:
1156 	case MGSL_IOCGXSYNC:
1157 	case MGSL_IOCGXCTRL:
1158 		rc = ioctl(tty, cmd, (unsigned long)compat_ptr(arg));
1159 		break;
1160 	default:
1161 		rc = ioctl(tty, cmd, arg);
1162 	}
1163 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1164 	return rc;
1165 }
1166 #else
1167 #define slgt_compat_ioctl NULL
1168 #endif /* ifdef CONFIG_COMPAT */
1169 
1170 /*
1171  * proc fs support
1172  */
1173 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1174 {
1175 	char stat_buf[30];
1176 	unsigned long flags;
1177 
1178 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1179 		      info->device_name, info->phys_reg_addr,
1180 		      info->irq_level, info->max_frame_size);
1181 
1182 	/* output current serial signal states */
1183 	spin_lock_irqsave(&info->lock,flags);
1184 	get_signals(info);
1185 	spin_unlock_irqrestore(&info->lock,flags);
1186 
1187 	stat_buf[0] = 0;
1188 	stat_buf[1] = 0;
1189 	if (info->signals & SerialSignal_RTS)
1190 		strcat(stat_buf, "|RTS");
1191 	if (info->signals & SerialSignal_CTS)
1192 		strcat(stat_buf, "|CTS");
1193 	if (info->signals & SerialSignal_DTR)
1194 		strcat(stat_buf, "|DTR");
1195 	if (info->signals & SerialSignal_DSR)
1196 		strcat(stat_buf, "|DSR");
1197 	if (info->signals & SerialSignal_DCD)
1198 		strcat(stat_buf, "|CD");
1199 	if (info->signals & SerialSignal_RI)
1200 		strcat(stat_buf, "|RI");
1201 
1202 	if (info->params.mode != MGSL_MODE_ASYNC) {
1203 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1204 			       info->icount.txok, info->icount.rxok);
1205 		if (info->icount.txunder)
1206 			seq_printf(m, " txunder:%d", info->icount.txunder);
1207 		if (info->icount.txabort)
1208 			seq_printf(m, " txabort:%d", info->icount.txabort);
1209 		if (info->icount.rxshort)
1210 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1211 		if (info->icount.rxlong)
1212 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1213 		if (info->icount.rxover)
1214 			seq_printf(m, " rxover:%d", info->icount.rxover);
1215 		if (info->icount.rxcrc)
1216 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1217 	} else {
1218 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1219 			       info->icount.tx, info->icount.rx);
1220 		if (info->icount.frame)
1221 			seq_printf(m, " fe:%d", info->icount.frame);
1222 		if (info->icount.parity)
1223 			seq_printf(m, " pe:%d", info->icount.parity);
1224 		if (info->icount.brk)
1225 			seq_printf(m, " brk:%d", info->icount.brk);
1226 		if (info->icount.overrun)
1227 			seq_printf(m, " oe:%d", info->icount.overrun);
1228 	}
1229 
1230 	/* Append serial signal status to end */
1231 	seq_printf(m, " %s\n", stat_buf+1);
1232 
1233 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1234 		       info->tx_active,info->bh_requested,info->bh_running,
1235 		       info->pending_bh);
1236 }
1237 
1238 /* Called to print information about devices
1239  */
1240 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1241 {
1242 	struct slgt_info *info;
1243 
1244 	seq_puts(m, "synclink_gt driver\n");
1245 
1246 	info = slgt_device_list;
1247 	while( info ) {
1248 		line_info(m, info);
1249 		info = info->next_device;
1250 	}
1251 	return 0;
1252 }
1253 
1254 /*
1255  * return count of bytes in transmit buffer
1256  */
1257 static int chars_in_buffer(struct tty_struct *tty)
1258 {
1259 	struct slgt_info *info = tty->driver_data;
1260 	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()=%d\n", info->device_name, count));
1265 	return count;
1266 }
1267 
1268 /*
1269  * signal remote device to throttle send data (our receive data)
1270  */
1271 static void throttle(struct tty_struct * tty)
1272 {
1273 	struct slgt_info *info = tty->driver_data;
1274 	unsigned long flags;
1275 
1276 	if (sanity_check(info, tty->name, "throttle"))
1277 		return;
1278 	DBGINFO(("%s throttle\n", info->device_name));
1279 	if (I_IXOFF(tty))
1280 		send_xchar(tty, STOP_CHAR(tty));
1281 	if (C_CRTSCTS(tty)) {
1282 		spin_lock_irqsave(&info->lock,flags);
1283 		info->signals &= ~SerialSignal_RTS;
1284 		set_signals(info);
1285 		spin_unlock_irqrestore(&info->lock,flags);
1286 	}
1287 }
1288 
1289 /*
1290  * signal remote device to stop throttling send data (our receive data)
1291  */
1292 static void unthrottle(struct tty_struct * tty)
1293 {
1294 	struct slgt_info *info = tty->driver_data;
1295 	unsigned long flags;
1296 
1297 	if (sanity_check(info, tty->name, "unthrottle"))
1298 		return;
1299 	DBGINFO(("%s unthrottle\n", info->device_name));
1300 	if (I_IXOFF(tty)) {
1301 		if (info->x_char)
1302 			info->x_char = 0;
1303 		else
1304 			send_xchar(tty, START_CHAR(tty));
1305 	}
1306 	if (C_CRTSCTS(tty)) {
1307 		spin_lock_irqsave(&info->lock,flags);
1308 		info->signals |= SerialSignal_RTS;
1309 		set_signals(info);
1310 		spin_unlock_irqrestore(&info->lock,flags);
1311 	}
1312 }
1313 
1314 /*
1315  * set or clear transmit break condition
1316  * break_state	-1=set break condition, 0=clear
1317  */
1318 static int set_break(struct tty_struct *tty, int break_state)
1319 {
1320 	struct slgt_info *info = tty->driver_data;
1321 	unsigned short value;
1322 	unsigned long flags;
1323 
1324 	if (sanity_check(info, tty->name, "set_break"))
1325 		return -EINVAL;
1326 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1327 
1328 	spin_lock_irqsave(&info->lock,flags);
1329 	value = rd_reg16(info, TCR);
1330  	if (break_state == -1)
1331 		value |= BIT6;
1332 	else
1333 		value &= ~BIT6;
1334 	wr_reg16(info, TCR, value);
1335 	spin_unlock_irqrestore(&info->lock,flags);
1336 	return 0;
1337 }
1338 
1339 #if SYNCLINK_GENERIC_HDLC
1340 
1341 /**
1342  * hdlcdev_attach - called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1343  * @dev:      pointer to network device structure
1344  * @encoding: serial encoding setting
1345  * @parity:   FCS setting
1346  *
1347  * Set encoding and frame check sequence (FCS) options.
1348  *
1349  * Return: 0 if success, otherwise error code
1350  */
1351 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1352 			  unsigned short parity)
1353 {
1354 	struct slgt_info *info = dev_to_port(dev);
1355 	unsigned char  new_encoding;
1356 	unsigned short new_crctype;
1357 
1358 	/* return error if TTY interface open */
1359 	if (info->port.count)
1360 		return -EBUSY;
1361 
1362 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1363 
1364 	switch (encoding)
1365 	{
1366 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1367 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1368 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1369 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1370 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1371 	default: return -EINVAL;
1372 	}
1373 
1374 	switch (parity)
1375 	{
1376 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1377 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1378 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1379 	default: return -EINVAL;
1380 	}
1381 
1382 	info->params.encoding = new_encoding;
1383 	info->params.crc_type = new_crctype;
1384 
1385 	/* if network interface up, reprogram hardware */
1386 	if (info->netcount)
1387 		program_hw(info);
1388 
1389 	return 0;
1390 }
1391 
1392 /**
1393  * hdlcdev_xmit - called by generic HDLC layer to send a frame
1394  * @skb: socket buffer containing HDLC frame
1395  * @dev: pointer to network device structure
1396  */
1397 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1398 				      struct net_device *dev)
1399 {
1400 	struct slgt_info *info = dev_to_port(dev);
1401 	unsigned long flags;
1402 
1403 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1404 
1405 	if (!skb->len)
1406 		return NETDEV_TX_OK;
1407 
1408 	/* stop sending until this frame completes */
1409 	netif_stop_queue(dev);
1410 
1411 	/* update network statistics */
1412 	dev->stats.tx_packets++;
1413 	dev->stats.tx_bytes += skb->len;
1414 
1415 	/* save start time for transmit timeout detection */
1416 	netif_trans_update(dev);
1417 
1418 	spin_lock_irqsave(&info->lock, flags);
1419 	tx_load(info, skb->data, skb->len);
1420 	spin_unlock_irqrestore(&info->lock, flags);
1421 
1422 	/* done with socket buffer, so free it */
1423 	dev_kfree_skb(skb);
1424 
1425 	return NETDEV_TX_OK;
1426 }
1427 
1428 /**
1429  * hdlcdev_open - called by network layer when interface enabled
1430  * @dev: pointer to network device structure
1431  *
1432  * Claim resources and initialize hardware.
1433  *
1434  * Return: 0 if success, otherwise error code
1435  */
1436 static int hdlcdev_open(struct net_device *dev)
1437 {
1438 	struct slgt_info *info = dev_to_port(dev);
1439 	int rc;
1440 	unsigned long flags;
1441 
1442 	if (!try_module_get(THIS_MODULE))
1443 		return -EBUSY;
1444 
1445 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1446 
1447 	/* generic HDLC layer open processing */
1448 	rc = hdlc_open(dev);
1449 	if (rc)
1450 		return rc;
1451 
1452 	/* arbitrate between network and tty opens */
1453 	spin_lock_irqsave(&info->netlock, flags);
1454 	if (info->port.count != 0 || info->netcount != 0) {
1455 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1456 		spin_unlock_irqrestore(&info->netlock, flags);
1457 		return -EBUSY;
1458 	}
1459 	info->netcount=1;
1460 	spin_unlock_irqrestore(&info->netlock, flags);
1461 
1462 	/* claim resources and init adapter */
1463 	if ((rc = startup(info)) != 0) {
1464 		spin_lock_irqsave(&info->netlock, flags);
1465 		info->netcount=0;
1466 		spin_unlock_irqrestore(&info->netlock, flags);
1467 		return rc;
1468 	}
1469 
1470 	/* assert RTS and DTR, apply hardware settings */
1471 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1472 	program_hw(info);
1473 
1474 	/* enable network layer transmit */
1475 	netif_trans_update(dev);
1476 	netif_start_queue(dev);
1477 
1478 	/* inform generic HDLC layer of current DCD status */
1479 	spin_lock_irqsave(&info->lock, flags);
1480 	get_signals(info);
1481 	spin_unlock_irqrestore(&info->lock, flags);
1482 	if (info->signals & SerialSignal_DCD)
1483 		netif_carrier_on(dev);
1484 	else
1485 		netif_carrier_off(dev);
1486 	return 0;
1487 }
1488 
1489 /**
1490  * hdlcdev_close - called by network layer when interface is disabled
1491  * @dev:  pointer to network device structure
1492  *
1493  * Shutdown hardware and release resources.
1494  *
1495  * Return: 0 if success, otherwise error code
1496  */
1497 static int hdlcdev_close(struct net_device *dev)
1498 {
1499 	struct slgt_info *info = dev_to_port(dev);
1500 	unsigned long flags;
1501 
1502 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1503 
1504 	netif_stop_queue(dev);
1505 
1506 	/* shutdown adapter and release resources */
1507 	shutdown(info);
1508 
1509 	hdlc_close(dev);
1510 
1511 	spin_lock_irqsave(&info->netlock, flags);
1512 	info->netcount=0;
1513 	spin_unlock_irqrestore(&info->netlock, flags);
1514 
1515 	module_put(THIS_MODULE);
1516 	return 0;
1517 }
1518 
1519 /**
1520  * hdlcdev_ioctl - called by network layer to process IOCTL call to network device
1521  * @dev: pointer to network device structure
1522  * @ifr: pointer to network interface request structure
1523  * @cmd: IOCTL command code
1524  *
1525  * Return: 0 if success, otherwise error code
1526  */
1527 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1528 {
1529 	const size_t size = sizeof(sync_serial_settings);
1530 	sync_serial_settings new_line;
1531 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1532 	struct slgt_info *info = dev_to_port(dev);
1533 	unsigned int flags;
1534 
1535 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1536 
1537 	/* return error if TTY interface open */
1538 	if (info->port.count)
1539 		return -EBUSY;
1540 
1541 	if (cmd != SIOCWANDEV)
1542 		return hdlc_ioctl(dev, ifr, cmd);
1543 
1544 	memset(&new_line, 0, sizeof(new_line));
1545 
1546 	switch(ifr->ifr_settings.type) {
1547 	case IF_GET_IFACE: /* return current sync_serial_settings */
1548 
1549 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1550 		if (ifr->ifr_settings.size < size) {
1551 			ifr->ifr_settings.size = size; /* data size wanted */
1552 			return -ENOBUFS;
1553 		}
1554 
1555 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1556 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1557 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1558 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1559 
1560 		switch (flags){
1561 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1562 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1563 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1564 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1565 		default: new_line.clock_type = CLOCK_DEFAULT;
1566 		}
1567 
1568 		new_line.clock_rate = info->params.clock_speed;
1569 		new_line.loopback   = info->params.loopback ? 1:0;
1570 
1571 		if (copy_to_user(line, &new_line, size))
1572 			return -EFAULT;
1573 		return 0;
1574 
1575 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1576 
1577 		if(!capable(CAP_NET_ADMIN))
1578 			return -EPERM;
1579 		if (copy_from_user(&new_line, line, size))
1580 			return -EFAULT;
1581 
1582 		switch (new_line.clock_type)
1583 		{
1584 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1585 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1586 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1587 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1588 		case CLOCK_DEFAULT:  flags = info->params.flags &
1589 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1590 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1591 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1592 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1593 		default: return -EINVAL;
1594 		}
1595 
1596 		if (new_line.loopback != 0 && new_line.loopback != 1)
1597 			return -EINVAL;
1598 
1599 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1600 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1601 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1602 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1603 		info->params.flags |= flags;
1604 
1605 		info->params.loopback = new_line.loopback;
1606 
1607 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1608 			info->params.clock_speed = new_line.clock_rate;
1609 		else
1610 			info->params.clock_speed = 0;
1611 
1612 		/* if network interface up, reprogram hardware */
1613 		if (info->netcount)
1614 			program_hw(info);
1615 		return 0;
1616 
1617 	default:
1618 		return hdlc_ioctl(dev, ifr, cmd);
1619 	}
1620 }
1621 
1622 /**
1623  * hdlcdev_tx_timeout - called by network layer when transmit timeout is detected
1624  * @dev: pointer to network device structure
1625  * @txqueue: unused
1626  */
1627 static void hdlcdev_tx_timeout(struct net_device *dev, unsigned int txqueue)
1628 {
1629 	struct slgt_info *info = dev_to_port(dev);
1630 	unsigned long flags;
1631 
1632 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1633 
1634 	dev->stats.tx_errors++;
1635 	dev->stats.tx_aborted_errors++;
1636 
1637 	spin_lock_irqsave(&info->lock,flags);
1638 	tx_stop(info);
1639 	spin_unlock_irqrestore(&info->lock,flags);
1640 
1641 	netif_wake_queue(dev);
1642 }
1643 
1644 /**
1645  * hdlcdev_tx_done - called by device driver when transmit completes
1646  * @info: pointer to device instance information
1647  *
1648  * Reenable network layer transmit if stopped.
1649  */
1650 static void hdlcdev_tx_done(struct slgt_info *info)
1651 {
1652 	if (netif_queue_stopped(info->netdev))
1653 		netif_wake_queue(info->netdev);
1654 }
1655 
1656 /**
1657  * hdlcdev_rx - called by device driver when frame received
1658  * @info: pointer to device instance information
1659  * @buf:  pointer to buffer contianing frame data
1660  * @size: count of data bytes in buf
1661  *
1662  * Pass frame to network layer.
1663  */
1664 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1665 {
1666 	struct sk_buff *skb = dev_alloc_skb(size);
1667 	struct net_device *dev = info->netdev;
1668 
1669 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1670 
1671 	if (skb == NULL) {
1672 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1673 		dev->stats.rx_dropped++;
1674 		return;
1675 	}
1676 
1677 	skb_put_data(skb, buf, size);
1678 
1679 	skb->protocol = hdlc_type_trans(skb, dev);
1680 
1681 	dev->stats.rx_packets++;
1682 	dev->stats.rx_bytes += size;
1683 
1684 	netif_rx(skb);
1685 }
1686 
1687 static const struct net_device_ops hdlcdev_ops = {
1688 	.ndo_open       = hdlcdev_open,
1689 	.ndo_stop       = hdlcdev_close,
1690 	.ndo_start_xmit = hdlc_start_xmit,
1691 	.ndo_do_ioctl   = hdlcdev_ioctl,
1692 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1693 };
1694 
1695 /**
1696  * hdlcdev_init - called by device driver when adding device instance
1697  * @info: pointer to device instance information
1698  *
1699  * Do generic HDLC initialization.
1700  *
1701  * Return: 0 if success, otherwise error code
1702  */
1703 static int hdlcdev_init(struct slgt_info *info)
1704 {
1705 	int rc;
1706 	struct net_device *dev;
1707 	hdlc_device *hdlc;
1708 
1709 	/* allocate and initialize network and HDLC layer objects */
1710 
1711 	dev = alloc_hdlcdev(info);
1712 	if (!dev) {
1713 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1714 		return -ENOMEM;
1715 	}
1716 
1717 	/* for network layer reporting purposes only */
1718 	dev->mem_start = info->phys_reg_addr;
1719 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1720 	dev->irq       = info->irq_level;
1721 
1722 	/* network layer callbacks and settings */
1723 	dev->netdev_ops	    = &hdlcdev_ops;
1724 	dev->watchdog_timeo = 10 * HZ;
1725 	dev->tx_queue_len   = 50;
1726 
1727 	/* generic HDLC layer callbacks and settings */
1728 	hdlc         = dev_to_hdlc(dev);
1729 	hdlc->attach = hdlcdev_attach;
1730 	hdlc->xmit   = hdlcdev_xmit;
1731 
1732 	/* register objects with HDLC layer */
1733 	rc = register_hdlc_device(dev);
1734 	if (rc) {
1735 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1736 		free_netdev(dev);
1737 		return rc;
1738 	}
1739 
1740 	info->netdev = dev;
1741 	return 0;
1742 }
1743 
1744 /**
1745  * hdlcdev_exit - called by device driver when removing device instance
1746  * @info: pointer to device instance information
1747  *
1748  * Do generic HDLC cleanup.
1749  */
1750 static void hdlcdev_exit(struct slgt_info *info)
1751 {
1752 	unregister_hdlc_device(info->netdev);
1753 	free_netdev(info->netdev);
1754 	info->netdev = NULL;
1755 }
1756 
1757 #endif /* ifdef CONFIG_HDLC */
1758 
1759 /*
1760  * get async data from rx DMA buffers
1761  */
1762 static void rx_async(struct slgt_info *info)
1763 {
1764  	struct mgsl_icount *icount = &info->icount;
1765 	unsigned int start, end;
1766 	unsigned char *p;
1767 	unsigned char status;
1768 	struct slgt_desc *bufs = info->rbufs;
1769 	int i, count;
1770 	int chars = 0;
1771 	int stat;
1772 	unsigned char ch;
1773 
1774 	start = end = info->rbuf_current;
1775 
1776 	while(desc_complete(bufs[end])) {
1777 		count = desc_count(bufs[end]) - info->rbuf_index;
1778 		p     = bufs[end].buf + info->rbuf_index;
1779 
1780 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1781 		DBGDATA(info, p, count, "rx");
1782 
1783 		for(i=0 ; i < count; i+=2, p+=2) {
1784 			ch = *p;
1785 			icount->rx++;
1786 
1787 			stat = 0;
1788 
1789 			status = *(p + 1) & (BIT1 + BIT0);
1790 			if (status) {
1791 				if (status & BIT1)
1792 					icount->parity++;
1793 				else if (status & BIT0)
1794 					icount->frame++;
1795 				/* discard char if tty control flags say so */
1796 				if (status & info->ignore_status_mask)
1797 					continue;
1798 				if (status & BIT1)
1799 					stat = TTY_PARITY;
1800 				else if (status & BIT0)
1801 					stat = TTY_FRAME;
1802 			}
1803 			tty_insert_flip_char(&info->port, ch, stat);
1804 			chars++;
1805 		}
1806 
1807 		if (i < count) {
1808 			/* receive buffer not completed */
1809 			info->rbuf_index += i;
1810 			mod_timer(&info->rx_timer, jiffies + 1);
1811 			break;
1812 		}
1813 
1814 		info->rbuf_index = 0;
1815 		free_rbufs(info, end, end);
1816 
1817 		if (++end == info->rbuf_count)
1818 			end = 0;
1819 
1820 		/* if entire list searched then no frame available */
1821 		if (end == start)
1822 			break;
1823 	}
1824 
1825 	if (chars)
1826 		tty_flip_buffer_push(&info->port);
1827 }
1828 
1829 /*
1830  * return next bottom half action to perform
1831  */
1832 static int bh_action(struct slgt_info *info)
1833 {
1834 	unsigned long flags;
1835 	int rc;
1836 
1837 	spin_lock_irqsave(&info->lock,flags);
1838 
1839 	if (info->pending_bh & BH_RECEIVE) {
1840 		info->pending_bh &= ~BH_RECEIVE;
1841 		rc = BH_RECEIVE;
1842 	} else if (info->pending_bh & BH_TRANSMIT) {
1843 		info->pending_bh &= ~BH_TRANSMIT;
1844 		rc = BH_TRANSMIT;
1845 	} else if (info->pending_bh & BH_STATUS) {
1846 		info->pending_bh &= ~BH_STATUS;
1847 		rc = BH_STATUS;
1848 	} else {
1849 		/* Mark BH routine as complete */
1850 		info->bh_running = false;
1851 		info->bh_requested = false;
1852 		rc = 0;
1853 	}
1854 
1855 	spin_unlock_irqrestore(&info->lock,flags);
1856 
1857 	return rc;
1858 }
1859 
1860 /*
1861  * perform bottom half processing
1862  */
1863 static void bh_handler(struct work_struct *work)
1864 {
1865 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1866 	int action;
1867 
1868 	info->bh_running = true;
1869 
1870 	while((action = bh_action(info))) {
1871 		switch (action) {
1872 		case BH_RECEIVE:
1873 			DBGBH(("%s bh receive\n", info->device_name));
1874 			switch(info->params.mode) {
1875 			case MGSL_MODE_ASYNC:
1876 				rx_async(info);
1877 				break;
1878 			case MGSL_MODE_HDLC:
1879 				while(rx_get_frame(info));
1880 				break;
1881 			case MGSL_MODE_RAW:
1882 			case MGSL_MODE_MONOSYNC:
1883 			case MGSL_MODE_BISYNC:
1884 			case MGSL_MODE_XSYNC:
1885 				while(rx_get_buf(info));
1886 				break;
1887 			}
1888 			/* restart receiver if rx DMA buffers exhausted */
1889 			if (info->rx_restart)
1890 				rx_start(info);
1891 			break;
1892 		case BH_TRANSMIT:
1893 			bh_transmit(info);
1894 			break;
1895 		case BH_STATUS:
1896 			DBGBH(("%s bh status\n", info->device_name));
1897 			info->ri_chkcount = 0;
1898 			info->dsr_chkcount = 0;
1899 			info->dcd_chkcount = 0;
1900 			info->cts_chkcount = 0;
1901 			break;
1902 		default:
1903 			DBGBH(("%s unknown action\n", info->device_name));
1904 			break;
1905 		}
1906 	}
1907 	DBGBH(("%s bh_handler exit\n", info->device_name));
1908 }
1909 
1910 static void bh_transmit(struct slgt_info *info)
1911 {
1912 	struct tty_struct *tty = info->port.tty;
1913 
1914 	DBGBH(("%s bh_transmit\n", info->device_name));
1915 	if (tty)
1916 		tty_wakeup(tty);
1917 }
1918 
1919 static void dsr_change(struct slgt_info *info, unsigned short status)
1920 {
1921 	if (status & BIT3) {
1922 		info->signals |= SerialSignal_DSR;
1923 		info->input_signal_events.dsr_up++;
1924 	} else {
1925 		info->signals &= ~SerialSignal_DSR;
1926 		info->input_signal_events.dsr_down++;
1927 	}
1928 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1929 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1930 		slgt_irq_off(info, IRQ_DSR);
1931 		return;
1932 	}
1933 	info->icount.dsr++;
1934 	wake_up_interruptible(&info->status_event_wait_q);
1935 	wake_up_interruptible(&info->event_wait_q);
1936 	info->pending_bh |= BH_STATUS;
1937 }
1938 
1939 static void cts_change(struct slgt_info *info, unsigned short status)
1940 {
1941 	if (status & BIT2) {
1942 		info->signals |= SerialSignal_CTS;
1943 		info->input_signal_events.cts_up++;
1944 	} else {
1945 		info->signals &= ~SerialSignal_CTS;
1946 		info->input_signal_events.cts_down++;
1947 	}
1948 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
1949 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1950 		slgt_irq_off(info, IRQ_CTS);
1951 		return;
1952 	}
1953 	info->icount.cts++;
1954 	wake_up_interruptible(&info->status_event_wait_q);
1955 	wake_up_interruptible(&info->event_wait_q);
1956 	info->pending_bh |= BH_STATUS;
1957 
1958 	if (tty_port_cts_enabled(&info->port)) {
1959 		if (info->port.tty) {
1960 			if (info->port.tty->hw_stopped) {
1961 				if (info->signals & SerialSignal_CTS) {
1962 		 			info->port.tty->hw_stopped = 0;
1963 					info->pending_bh |= BH_TRANSMIT;
1964 					return;
1965 				}
1966 			} else {
1967 				if (!(info->signals & SerialSignal_CTS))
1968 		 			info->port.tty->hw_stopped = 1;
1969 			}
1970 		}
1971 	}
1972 }
1973 
1974 static void dcd_change(struct slgt_info *info, unsigned short status)
1975 {
1976 	if (status & BIT1) {
1977 		info->signals |= SerialSignal_DCD;
1978 		info->input_signal_events.dcd_up++;
1979 	} else {
1980 		info->signals &= ~SerialSignal_DCD;
1981 		info->input_signal_events.dcd_down++;
1982 	}
1983 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
1984 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1985 		slgt_irq_off(info, IRQ_DCD);
1986 		return;
1987 	}
1988 	info->icount.dcd++;
1989 #if SYNCLINK_GENERIC_HDLC
1990 	if (info->netcount) {
1991 		if (info->signals & SerialSignal_DCD)
1992 			netif_carrier_on(info->netdev);
1993 		else
1994 			netif_carrier_off(info->netdev);
1995 	}
1996 #endif
1997 	wake_up_interruptible(&info->status_event_wait_q);
1998 	wake_up_interruptible(&info->event_wait_q);
1999 	info->pending_bh |= BH_STATUS;
2000 
2001 	if (tty_port_check_carrier(&info->port)) {
2002 		if (info->signals & SerialSignal_DCD)
2003 			wake_up_interruptible(&info->port.open_wait);
2004 		else {
2005 			if (info->port.tty)
2006 				tty_hangup(info->port.tty);
2007 		}
2008 	}
2009 }
2010 
2011 static void ri_change(struct slgt_info *info, unsigned short status)
2012 {
2013 	if (status & BIT0) {
2014 		info->signals |= SerialSignal_RI;
2015 		info->input_signal_events.ri_up++;
2016 	} else {
2017 		info->signals &= ~SerialSignal_RI;
2018 		info->input_signal_events.ri_down++;
2019 	}
2020 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2021 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2022 		slgt_irq_off(info, IRQ_RI);
2023 		return;
2024 	}
2025 	info->icount.rng++;
2026 	wake_up_interruptible(&info->status_event_wait_q);
2027 	wake_up_interruptible(&info->event_wait_q);
2028 	info->pending_bh |= BH_STATUS;
2029 }
2030 
2031 static void isr_rxdata(struct slgt_info *info)
2032 {
2033 	unsigned int count = info->rbuf_fill_count;
2034 	unsigned int i = info->rbuf_fill_index;
2035 	unsigned short reg;
2036 
2037 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2038 		reg = rd_reg16(info, RDR);
2039 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2040 		if (desc_complete(info->rbufs[i])) {
2041 			/* all buffers full */
2042 			rx_stop(info);
2043 			info->rx_restart = true;
2044 			continue;
2045 		}
2046 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2047 		/* async mode saves status byte to buffer for each data byte */
2048 		if (info->params.mode == MGSL_MODE_ASYNC)
2049 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2050 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2051 			/* buffer full or end of frame */
2052 			set_desc_count(info->rbufs[i], count);
2053 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2054 			info->rbuf_fill_count = count = 0;
2055 			if (++i == info->rbuf_count)
2056 				i = 0;
2057 			info->pending_bh |= BH_RECEIVE;
2058 		}
2059 	}
2060 
2061 	info->rbuf_fill_index = i;
2062 	info->rbuf_fill_count = count;
2063 }
2064 
2065 static void isr_serial(struct slgt_info *info)
2066 {
2067 	unsigned short status = rd_reg16(info, SSR);
2068 
2069 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2070 
2071 	wr_reg16(info, SSR, status); /* clear pending */
2072 
2073 	info->irq_occurred = true;
2074 
2075 	if (info->params.mode == MGSL_MODE_ASYNC) {
2076 		if (status & IRQ_TXIDLE) {
2077 			if (info->tx_active)
2078 				isr_txeom(info, status);
2079 		}
2080 		if (info->rx_pio && (status & IRQ_RXDATA))
2081 			isr_rxdata(info);
2082 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2083 			info->icount.brk++;
2084 			/* process break detection if tty control allows */
2085 			if (info->port.tty) {
2086 				if (!(status & info->ignore_status_mask)) {
2087 					if (info->read_status_mask & MASK_BREAK) {
2088 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2089 						if (info->port.flags & ASYNC_SAK)
2090 							do_SAK(info->port.tty);
2091 					}
2092 				}
2093 			}
2094 		}
2095 	} else {
2096 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2097 			isr_txeom(info, status);
2098 		if (info->rx_pio && (status & IRQ_RXDATA))
2099 			isr_rxdata(info);
2100 		if (status & IRQ_RXIDLE) {
2101 			if (status & RXIDLE)
2102 				info->icount.rxidle++;
2103 			else
2104 				info->icount.exithunt++;
2105 			wake_up_interruptible(&info->event_wait_q);
2106 		}
2107 
2108 		if (status & IRQ_RXOVER)
2109 			rx_start(info);
2110 	}
2111 
2112 	if (status & IRQ_DSR)
2113 		dsr_change(info, status);
2114 	if (status & IRQ_CTS)
2115 		cts_change(info, status);
2116 	if (status & IRQ_DCD)
2117 		dcd_change(info, status);
2118 	if (status & IRQ_RI)
2119 		ri_change(info, status);
2120 }
2121 
2122 static void isr_rdma(struct slgt_info *info)
2123 {
2124 	unsigned int status = rd_reg32(info, RDCSR);
2125 
2126 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2127 
2128 	/* RDCSR (rx DMA control/status)
2129 	 *
2130 	 * 31..07  reserved
2131 	 * 06      save status byte to DMA buffer
2132 	 * 05      error
2133 	 * 04      eol (end of list)
2134 	 * 03      eob (end of buffer)
2135 	 * 02      IRQ enable
2136 	 * 01      reset
2137 	 * 00      enable
2138 	 */
2139 	wr_reg32(info, RDCSR, status);	/* clear pending */
2140 
2141 	if (status & (BIT5 + BIT4)) {
2142 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2143 		info->rx_restart = true;
2144 	}
2145 	info->pending_bh |= BH_RECEIVE;
2146 }
2147 
2148 static void isr_tdma(struct slgt_info *info)
2149 {
2150 	unsigned int status = rd_reg32(info, TDCSR);
2151 
2152 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2153 
2154 	/* TDCSR (tx DMA control/status)
2155 	 *
2156 	 * 31..06  reserved
2157 	 * 05      error
2158 	 * 04      eol (end of list)
2159 	 * 03      eob (end of buffer)
2160 	 * 02      IRQ enable
2161 	 * 01      reset
2162 	 * 00      enable
2163 	 */
2164 	wr_reg32(info, TDCSR, status);	/* clear pending */
2165 
2166 	if (status & (BIT5 + BIT4 + BIT3)) {
2167 		// another transmit buffer has completed
2168 		// run bottom half to get more send data from user
2169 		info->pending_bh |= BH_TRANSMIT;
2170 	}
2171 }
2172 
2173 /*
2174  * return true if there are unsent tx DMA buffers, otherwise false
2175  *
2176  * if there are unsent buffers then info->tbuf_start
2177  * is set to index of first unsent buffer
2178  */
2179 static bool unsent_tbufs(struct slgt_info *info)
2180 {
2181 	unsigned int i = info->tbuf_current;
2182 	bool rc = false;
2183 
2184 	/*
2185 	 * search backwards from last loaded buffer (precedes tbuf_current)
2186 	 * for first unsent buffer (desc_count > 0)
2187 	 */
2188 
2189 	do {
2190 		if (i)
2191 			i--;
2192 		else
2193 			i = info->tbuf_count - 1;
2194 		if (!desc_count(info->tbufs[i]))
2195 			break;
2196 		info->tbuf_start = i;
2197 		rc = true;
2198 	} while (i != info->tbuf_current);
2199 
2200 	return rc;
2201 }
2202 
2203 static void isr_txeom(struct slgt_info *info, unsigned short status)
2204 {
2205 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2206 
2207 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2208 	tdma_reset(info);
2209 	if (status & IRQ_TXUNDER) {
2210 		unsigned short val = rd_reg16(info, TCR);
2211 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2212 		wr_reg16(info, TCR, val); /* clear reset bit */
2213 	}
2214 
2215 	if (info->tx_active) {
2216 		if (info->params.mode != MGSL_MODE_ASYNC) {
2217 			if (status & IRQ_TXUNDER)
2218 				info->icount.txunder++;
2219 			else if (status & IRQ_TXIDLE)
2220 				info->icount.txok++;
2221 		}
2222 
2223 		if (unsent_tbufs(info)) {
2224 			tx_start(info);
2225 			update_tx_timer(info);
2226 			return;
2227 		}
2228 		info->tx_active = false;
2229 
2230 		del_timer(&info->tx_timer);
2231 
2232 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2233 			info->signals &= ~SerialSignal_RTS;
2234 			info->drop_rts_on_tx_done = false;
2235 			set_signals(info);
2236 		}
2237 
2238 #if SYNCLINK_GENERIC_HDLC
2239 		if (info->netcount)
2240 			hdlcdev_tx_done(info);
2241 		else
2242 #endif
2243 		{
2244 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2245 				tx_stop(info);
2246 				return;
2247 			}
2248 			info->pending_bh |= BH_TRANSMIT;
2249 		}
2250 	}
2251 }
2252 
2253 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2254 {
2255 	struct cond_wait *w, *prev;
2256 
2257 	/* wake processes waiting for specific transitions */
2258 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2259 		if (w->data & changed) {
2260 			w->data = state;
2261 			wake_up_interruptible(&w->q);
2262 			if (prev != NULL)
2263 				prev->next = w->next;
2264 			else
2265 				info->gpio_wait_q = w->next;
2266 		} else
2267 			prev = w;
2268 	}
2269 }
2270 
2271 /* interrupt service routine
2272  *
2273  * 	irq	interrupt number
2274  * 	dev_id	device ID supplied during interrupt registration
2275  */
2276 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2277 {
2278 	struct slgt_info *info = dev_id;
2279 	unsigned int gsr;
2280 	unsigned int i;
2281 
2282 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2283 
2284 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2285 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2286 		info->irq_occurred = true;
2287 		for(i=0; i < info->port_count ; i++) {
2288 			if (info->port_array[i] == NULL)
2289 				continue;
2290 			spin_lock(&info->port_array[i]->lock);
2291 			if (gsr & (BIT8 << i))
2292 				isr_serial(info->port_array[i]);
2293 			if (gsr & (BIT16 << (i*2)))
2294 				isr_rdma(info->port_array[i]);
2295 			if (gsr & (BIT17 << (i*2)))
2296 				isr_tdma(info->port_array[i]);
2297 			spin_unlock(&info->port_array[i]->lock);
2298 		}
2299 	}
2300 
2301 	if (info->gpio_present) {
2302 		unsigned int state;
2303 		unsigned int changed;
2304 		spin_lock(&info->lock);
2305 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2306 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2307 			/* read latched state of GPIO signals */
2308 			state = rd_reg32(info, IOVR);
2309 			/* clear pending GPIO interrupt bits */
2310 			wr_reg32(info, IOSR, changed);
2311 			for (i=0 ; i < info->port_count ; i++) {
2312 				if (info->port_array[i] != NULL)
2313 					isr_gpio(info->port_array[i], changed, state);
2314 			}
2315 		}
2316 		spin_unlock(&info->lock);
2317 	}
2318 
2319 	for(i=0; i < info->port_count ; i++) {
2320 		struct slgt_info *port = info->port_array[i];
2321 		if (port == NULL)
2322 			continue;
2323 		spin_lock(&port->lock);
2324 		if ((port->port.count || port->netcount) &&
2325 		    port->pending_bh && !port->bh_running &&
2326 		    !port->bh_requested) {
2327 			DBGISR(("%s bh queued\n", port->device_name));
2328 			schedule_work(&port->task);
2329 			port->bh_requested = true;
2330 		}
2331 		spin_unlock(&port->lock);
2332 	}
2333 
2334 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2335 	return IRQ_HANDLED;
2336 }
2337 
2338 static int startup(struct slgt_info *info)
2339 {
2340 	DBGINFO(("%s startup\n", info->device_name));
2341 
2342 	if (tty_port_initialized(&info->port))
2343 		return 0;
2344 
2345 	if (!info->tx_buf) {
2346 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2347 		if (!info->tx_buf) {
2348 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2349 			return -ENOMEM;
2350 		}
2351 	}
2352 
2353 	info->pending_bh = 0;
2354 
2355 	memset(&info->icount, 0, sizeof(info->icount));
2356 
2357 	/* program hardware for current parameters */
2358 	change_params(info);
2359 
2360 	if (info->port.tty)
2361 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2362 
2363 	tty_port_set_initialized(&info->port, 1);
2364 
2365 	return 0;
2366 }
2367 
2368 /*
2369  *  called by close() and hangup() to shutdown hardware
2370  */
2371 static void shutdown(struct slgt_info *info)
2372 {
2373 	unsigned long flags;
2374 
2375 	if (!tty_port_initialized(&info->port))
2376 		return;
2377 
2378 	DBGINFO(("%s shutdown\n", info->device_name));
2379 
2380 	/* clear status wait queue because status changes */
2381 	/* can't happen after shutting down the hardware */
2382 	wake_up_interruptible(&info->status_event_wait_q);
2383 	wake_up_interruptible(&info->event_wait_q);
2384 
2385 	del_timer_sync(&info->tx_timer);
2386 	del_timer_sync(&info->rx_timer);
2387 
2388 	kfree(info->tx_buf);
2389 	info->tx_buf = NULL;
2390 
2391 	spin_lock_irqsave(&info->lock,flags);
2392 
2393 	tx_stop(info);
2394 	rx_stop(info);
2395 
2396 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2397 
2398  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2399 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2400 		set_signals(info);
2401 	}
2402 
2403 	flush_cond_wait(&info->gpio_wait_q);
2404 
2405 	spin_unlock_irqrestore(&info->lock,flags);
2406 
2407 	if (info->port.tty)
2408 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2409 
2410 	tty_port_set_initialized(&info->port, 0);
2411 }
2412 
2413 static void program_hw(struct slgt_info *info)
2414 {
2415 	unsigned long flags;
2416 
2417 	spin_lock_irqsave(&info->lock,flags);
2418 
2419 	rx_stop(info);
2420 	tx_stop(info);
2421 
2422 	if (info->params.mode != MGSL_MODE_ASYNC ||
2423 	    info->netcount)
2424 		sync_mode(info);
2425 	else
2426 		async_mode(info);
2427 
2428 	set_signals(info);
2429 
2430 	info->dcd_chkcount = 0;
2431 	info->cts_chkcount = 0;
2432 	info->ri_chkcount = 0;
2433 	info->dsr_chkcount = 0;
2434 
2435 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2436 	get_signals(info);
2437 
2438 	if (info->netcount ||
2439 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2440 		rx_start(info);
2441 
2442 	spin_unlock_irqrestore(&info->lock,flags);
2443 }
2444 
2445 /*
2446  * reconfigure adapter based on new parameters
2447  */
2448 static void change_params(struct slgt_info *info)
2449 {
2450 	unsigned cflag;
2451 	int bits_per_char;
2452 
2453 	if (!info->port.tty)
2454 		return;
2455 	DBGINFO(("%s change_params\n", info->device_name));
2456 
2457 	cflag = info->port.tty->termios.c_cflag;
2458 
2459 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2460 	/* otherwise assert RTS and DTR */
2461  	if (cflag & CBAUD)
2462 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2463 	else
2464 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2465 
2466 	/* byte size and parity */
2467 
2468 	switch (cflag & CSIZE) {
2469 	case CS5: info->params.data_bits = 5; break;
2470 	case CS6: info->params.data_bits = 6; break;
2471 	case CS7: info->params.data_bits = 7; break;
2472 	case CS8: info->params.data_bits = 8; break;
2473 	default:  info->params.data_bits = 7; break;
2474 	}
2475 
2476 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2477 
2478 	if (cflag & PARENB)
2479 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2480 	else
2481 		info->params.parity = ASYNC_PARITY_NONE;
2482 
2483 	/* calculate number of jiffies to transmit a full
2484 	 * FIFO (32 bytes) at specified data rate
2485 	 */
2486 	bits_per_char = info->params.data_bits +
2487 			info->params.stop_bits + 1;
2488 
2489 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2490 
2491 	if (info->params.data_rate) {
2492 		info->timeout = (32*HZ*bits_per_char) /
2493 				info->params.data_rate;
2494 	}
2495 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2496 
2497 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2498 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2499 
2500 	/* process tty input control flags */
2501 
2502 	info->read_status_mask = IRQ_RXOVER;
2503 	if (I_INPCK(info->port.tty))
2504 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2505 	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2506 		info->read_status_mask |= MASK_BREAK;
2507 	if (I_IGNPAR(info->port.tty))
2508 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2509 	if (I_IGNBRK(info->port.tty)) {
2510 		info->ignore_status_mask |= MASK_BREAK;
2511 		/* If ignoring parity and break indicators, ignore
2512 		 * overruns too.  (For real raw support).
2513 		 */
2514 		if (I_IGNPAR(info->port.tty))
2515 			info->ignore_status_mask |= MASK_OVERRUN;
2516 	}
2517 
2518 	program_hw(info);
2519 }
2520 
2521 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2522 {
2523 	DBGINFO(("%s get_stats\n",  info->device_name));
2524 	if (!user_icount) {
2525 		memset(&info->icount, 0, sizeof(info->icount));
2526 	} else {
2527 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2528 			return -EFAULT;
2529 	}
2530 	return 0;
2531 }
2532 
2533 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2534 {
2535 	DBGINFO(("%s get_params\n", info->device_name));
2536 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2537 		return -EFAULT;
2538 	return 0;
2539 }
2540 
2541 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2542 {
2543  	unsigned long flags;
2544 	MGSL_PARAMS tmp_params;
2545 
2546 	DBGINFO(("%s set_params\n", info->device_name));
2547 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2548 		return -EFAULT;
2549 
2550 	spin_lock_irqsave(&info->lock, flags);
2551 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2552 		info->base_clock = tmp_params.clock_speed;
2553 	else
2554 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2555 	spin_unlock_irqrestore(&info->lock, flags);
2556 
2557 	program_hw(info);
2558 
2559 	return 0;
2560 }
2561 
2562 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2563 {
2564 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2565 	if (put_user(info->idle_mode, idle_mode))
2566 		return -EFAULT;
2567 	return 0;
2568 }
2569 
2570 static int set_txidle(struct slgt_info *info, int idle_mode)
2571 {
2572  	unsigned long flags;
2573 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2574 	spin_lock_irqsave(&info->lock,flags);
2575 	info->idle_mode = idle_mode;
2576 	if (info->params.mode != MGSL_MODE_ASYNC)
2577 		tx_set_idle(info);
2578 	spin_unlock_irqrestore(&info->lock,flags);
2579 	return 0;
2580 }
2581 
2582 static int tx_enable(struct slgt_info *info, int enable)
2583 {
2584  	unsigned long flags;
2585 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2586 	spin_lock_irqsave(&info->lock,flags);
2587 	if (enable) {
2588 		if (!info->tx_enabled)
2589 			tx_start(info);
2590 	} else {
2591 		if (info->tx_enabled)
2592 			tx_stop(info);
2593 	}
2594 	spin_unlock_irqrestore(&info->lock,flags);
2595 	return 0;
2596 }
2597 
2598 /*
2599  * abort transmit HDLC frame
2600  */
2601 static int tx_abort(struct slgt_info *info)
2602 {
2603  	unsigned long flags;
2604 	DBGINFO(("%s tx_abort\n", info->device_name));
2605 	spin_lock_irqsave(&info->lock,flags);
2606 	tdma_reset(info);
2607 	spin_unlock_irqrestore(&info->lock,flags);
2608 	return 0;
2609 }
2610 
2611 static int rx_enable(struct slgt_info *info, int enable)
2612 {
2613  	unsigned long flags;
2614 	unsigned int rbuf_fill_level;
2615 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2616 	spin_lock_irqsave(&info->lock,flags);
2617 	/*
2618 	 * enable[31..16] = receive DMA buffer fill level
2619 	 * 0 = noop (leave fill level unchanged)
2620 	 * fill level must be multiple of 4 and <= buffer size
2621 	 */
2622 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2623 	if (rbuf_fill_level) {
2624 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2625 			spin_unlock_irqrestore(&info->lock, flags);
2626 			return -EINVAL;
2627 		}
2628 		info->rbuf_fill_level = rbuf_fill_level;
2629 		if (rbuf_fill_level < 128)
2630 			info->rx_pio = 1; /* PIO mode */
2631 		else
2632 			info->rx_pio = 0; /* DMA mode */
2633 		rx_stop(info); /* restart receiver to use new fill level */
2634 	}
2635 
2636 	/*
2637 	 * enable[1..0] = receiver enable command
2638 	 * 0 = disable
2639 	 * 1 = enable
2640 	 * 2 = enable or force hunt mode if already enabled
2641 	 */
2642 	enable &= 3;
2643 	if (enable) {
2644 		if (!info->rx_enabled)
2645 			rx_start(info);
2646 		else if (enable == 2) {
2647 			/* force hunt mode (write 1 to RCR[3]) */
2648 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2649 		}
2650 	} else {
2651 		if (info->rx_enabled)
2652 			rx_stop(info);
2653 	}
2654 	spin_unlock_irqrestore(&info->lock,flags);
2655 	return 0;
2656 }
2657 
2658 /*
2659  *  wait for specified event to occur
2660  */
2661 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2662 {
2663  	unsigned long flags;
2664 	int s;
2665 	int rc=0;
2666 	struct mgsl_icount cprev, cnow;
2667 	int events;
2668 	int mask;
2669 	struct	_input_signal_events oldsigs, newsigs;
2670 	DECLARE_WAITQUEUE(wait, current);
2671 
2672 	if (get_user(mask, mask_ptr))
2673 		return -EFAULT;
2674 
2675 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2676 
2677 	spin_lock_irqsave(&info->lock,flags);
2678 
2679 	/* return immediately if state matches requested events */
2680 	get_signals(info);
2681 	s = info->signals;
2682 
2683 	events = mask &
2684 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2685  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2686 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2687 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2688 	if (events) {
2689 		spin_unlock_irqrestore(&info->lock,flags);
2690 		goto exit;
2691 	}
2692 
2693 	/* save current irq counts */
2694 	cprev = info->icount;
2695 	oldsigs = info->input_signal_events;
2696 
2697 	/* enable hunt and idle irqs if needed */
2698 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2699 		unsigned short val = rd_reg16(info, SCR);
2700 		if (!(val & IRQ_RXIDLE))
2701 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2702 	}
2703 
2704 	set_current_state(TASK_INTERRUPTIBLE);
2705 	add_wait_queue(&info->event_wait_q, &wait);
2706 
2707 	spin_unlock_irqrestore(&info->lock,flags);
2708 
2709 	for(;;) {
2710 		schedule();
2711 		if (signal_pending(current)) {
2712 			rc = -ERESTARTSYS;
2713 			break;
2714 		}
2715 
2716 		/* get current irq counts */
2717 		spin_lock_irqsave(&info->lock,flags);
2718 		cnow = info->icount;
2719 		newsigs = info->input_signal_events;
2720 		set_current_state(TASK_INTERRUPTIBLE);
2721 		spin_unlock_irqrestore(&info->lock,flags);
2722 
2723 		/* if no change, wait aborted for some reason */
2724 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2725 		    newsigs.dsr_down == oldsigs.dsr_down &&
2726 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2727 		    newsigs.dcd_down == oldsigs.dcd_down &&
2728 		    newsigs.cts_up   == oldsigs.cts_up   &&
2729 		    newsigs.cts_down == oldsigs.cts_down &&
2730 		    newsigs.ri_up    == oldsigs.ri_up    &&
2731 		    newsigs.ri_down  == oldsigs.ri_down  &&
2732 		    cnow.exithunt    == cprev.exithunt   &&
2733 		    cnow.rxidle      == cprev.rxidle) {
2734 			rc = -EIO;
2735 			break;
2736 		}
2737 
2738 		events = mask &
2739 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2740 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2741 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2742 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2743 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2744 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2745 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2746 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2747 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2748 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2749 		if (events)
2750 			break;
2751 
2752 		cprev = cnow;
2753 		oldsigs = newsigs;
2754 	}
2755 
2756 	remove_wait_queue(&info->event_wait_q, &wait);
2757 	set_current_state(TASK_RUNNING);
2758 
2759 
2760 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2761 		spin_lock_irqsave(&info->lock,flags);
2762 		if (!waitqueue_active(&info->event_wait_q)) {
2763 			/* disable enable exit hunt mode/idle rcvd IRQs */
2764 			wr_reg16(info, SCR,
2765 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2766 		}
2767 		spin_unlock_irqrestore(&info->lock,flags);
2768 	}
2769 exit:
2770 	if (rc == 0)
2771 		rc = put_user(events, mask_ptr);
2772 	return rc;
2773 }
2774 
2775 static int get_interface(struct slgt_info *info, int __user *if_mode)
2776 {
2777 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2778 	if (put_user(info->if_mode, if_mode))
2779 		return -EFAULT;
2780 	return 0;
2781 }
2782 
2783 static int set_interface(struct slgt_info *info, int if_mode)
2784 {
2785  	unsigned long flags;
2786 	unsigned short val;
2787 
2788 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2789 	spin_lock_irqsave(&info->lock,flags);
2790 	info->if_mode = if_mode;
2791 
2792 	msc_set_vcr(info);
2793 
2794 	/* TCR (tx control) 07  1=RTS driver control */
2795 	val = rd_reg16(info, TCR);
2796 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2797 		val |= BIT7;
2798 	else
2799 		val &= ~BIT7;
2800 	wr_reg16(info, TCR, val);
2801 
2802 	spin_unlock_irqrestore(&info->lock,flags);
2803 	return 0;
2804 }
2805 
2806 static int get_xsync(struct slgt_info *info, int __user *xsync)
2807 {
2808 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2809 	if (put_user(info->xsync, xsync))
2810 		return -EFAULT;
2811 	return 0;
2812 }
2813 
2814 /*
2815  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2816  *
2817  * sync pattern is contained in least significant bytes of value
2818  * most significant byte of sync pattern is oldest (1st sent/detected)
2819  */
2820 static int set_xsync(struct slgt_info *info, int xsync)
2821 {
2822 	unsigned long flags;
2823 
2824 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2825 	spin_lock_irqsave(&info->lock, flags);
2826 	info->xsync = xsync;
2827 	wr_reg32(info, XSR, xsync);
2828 	spin_unlock_irqrestore(&info->lock, flags);
2829 	return 0;
2830 }
2831 
2832 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2833 {
2834 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2835 	if (put_user(info->xctrl, xctrl))
2836 		return -EFAULT;
2837 	return 0;
2838 }
2839 
2840 /*
2841  * set extended control options
2842  *
2843  * xctrl[31:19] reserved, must be zero
2844  * xctrl[18:17] extended sync pattern length in bytes
2845  *              00 = 1 byte  in xsr[7:0]
2846  *              01 = 2 bytes in xsr[15:0]
2847  *              10 = 3 bytes in xsr[23:0]
2848  *              11 = 4 bytes in xsr[31:0]
2849  * xctrl[16]    1 = enable terminal count, 0=disabled
2850  * xctrl[15:0]  receive terminal count for fixed length packets
2851  *              value is count minus one (0 = 1 byte packet)
2852  *              when terminal count is reached, receiver
2853  *              automatically returns to hunt mode and receive
2854  *              FIFO contents are flushed to DMA buffers with
2855  *              end of frame (EOF) status
2856  */
2857 static int set_xctrl(struct slgt_info *info, int xctrl)
2858 {
2859 	unsigned long flags;
2860 
2861 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2862 	spin_lock_irqsave(&info->lock, flags);
2863 	info->xctrl = xctrl;
2864 	wr_reg32(info, XCR, xctrl);
2865 	spin_unlock_irqrestore(&info->lock, flags);
2866 	return 0;
2867 }
2868 
2869 /*
2870  * set general purpose IO pin state and direction
2871  *
2872  * user_gpio fields:
2873  * state   each bit indicates a pin state
2874  * smask   set bit indicates pin state to set
2875  * dir     each bit indicates a pin direction (0=input, 1=output)
2876  * dmask   set bit indicates pin direction to set
2877  */
2878 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2879 {
2880  	unsigned long flags;
2881 	struct gpio_desc gpio;
2882 	__u32 data;
2883 
2884 	if (!info->gpio_present)
2885 		return -EINVAL;
2886 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2887 		return -EFAULT;
2888 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2889 		 info->device_name, gpio.state, gpio.smask,
2890 		 gpio.dir, gpio.dmask));
2891 
2892 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2893 	if (gpio.dmask) {
2894 		data = rd_reg32(info, IODR);
2895 		data |= gpio.dmask & gpio.dir;
2896 		data &= ~(gpio.dmask & ~gpio.dir);
2897 		wr_reg32(info, IODR, data);
2898 	}
2899 	if (gpio.smask) {
2900 		data = rd_reg32(info, IOVR);
2901 		data |= gpio.smask & gpio.state;
2902 		data &= ~(gpio.smask & ~gpio.state);
2903 		wr_reg32(info, IOVR, data);
2904 	}
2905 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2906 
2907 	return 0;
2908 }
2909 
2910 /*
2911  * get general purpose IO pin state and direction
2912  */
2913 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2914 {
2915 	struct gpio_desc gpio;
2916 	if (!info->gpio_present)
2917 		return -EINVAL;
2918 	gpio.state = rd_reg32(info, IOVR);
2919 	gpio.smask = 0xffffffff;
2920 	gpio.dir   = rd_reg32(info, IODR);
2921 	gpio.dmask = 0xffffffff;
2922 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2923 		return -EFAULT;
2924 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2925 		 info->device_name, gpio.state, gpio.dir));
2926 	return 0;
2927 }
2928 
2929 /*
2930  * conditional wait facility
2931  */
2932 static void init_cond_wait(struct cond_wait *w, unsigned int data)
2933 {
2934 	init_waitqueue_head(&w->q);
2935 	init_waitqueue_entry(&w->wait, current);
2936 	w->data = data;
2937 }
2938 
2939 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
2940 {
2941 	set_current_state(TASK_INTERRUPTIBLE);
2942 	add_wait_queue(&w->q, &w->wait);
2943 	w->next = *head;
2944 	*head = w;
2945 }
2946 
2947 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
2948 {
2949 	struct cond_wait *w, *prev;
2950 	remove_wait_queue(&cw->q, &cw->wait);
2951 	set_current_state(TASK_RUNNING);
2952 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
2953 		if (w == cw) {
2954 			if (prev != NULL)
2955 				prev->next = w->next;
2956 			else
2957 				*head = w->next;
2958 			break;
2959 		}
2960 	}
2961 }
2962 
2963 static void flush_cond_wait(struct cond_wait **head)
2964 {
2965 	while (*head != NULL) {
2966 		wake_up_interruptible(&(*head)->q);
2967 		*head = (*head)->next;
2968 	}
2969 }
2970 
2971 /*
2972  * wait for general purpose I/O pin(s) to enter specified state
2973  *
2974  * user_gpio fields:
2975  * state - bit indicates target pin state
2976  * smask - set bit indicates watched pin
2977  *
2978  * The wait ends when at least one watched pin enters the specified
2979  * state. When 0 (no error) is returned, user_gpio->state is set to the
2980  * state of all GPIO pins when the wait ends.
2981  *
2982  * Note: Each pin may be a dedicated input, dedicated output, or
2983  * configurable input/output. The number and configuration of pins
2984  * varies with the specific adapter model. Only input pins (dedicated
2985  * or configured) can be monitored with this function.
2986  */
2987 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2988 {
2989  	unsigned long flags;
2990 	int rc = 0;
2991 	struct gpio_desc gpio;
2992 	struct cond_wait wait;
2993 	u32 state;
2994 
2995 	if (!info->gpio_present)
2996 		return -EINVAL;
2997 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2998 		return -EFAULT;
2999 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3000 		 info->device_name, gpio.state, gpio.smask));
3001 	/* ignore output pins identified by set IODR bit */
3002 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3003 		return -EINVAL;
3004 	init_cond_wait(&wait, gpio.smask);
3005 
3006 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3007 	/* enable interrupts for watched pins */
3008 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3009 	/* get current pin states */
3010 	state = rd_reg32(info, IOVR);
3011 
3012 	if (gpio.smask & ~(state ^ gpio.state)) {
3013 		/* already in target state */
3014 		gpio.state = state;
3015 	} else {
3016 		/* wait for target state */
3017 		add_cond_wait(&info->gpio_wait_q, &wait);
3018 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3019 		schedule();
3020 		if (signal_pending(current))
3021 			rc = -ERESTARTSYS;
3022 		else
3023 			gpio.state = wait.data;
3024 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3025 		remove_cond_wait(&info->gpio_wait_q, &wait);
3026 	}
3027 
3028 	/* disable all GPIO interrupts if no waiting processes */
3029 	if (info->gpio_wait_q == NULL)
3030 		wr_reg32(info, IOER, 0);
3031 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3032 
3033 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3034 		rc = -EFAULT;
3035 	return rc;
3036 }
3037 
3038 static int modem_input_wait(struct slgt_info *info,int arg)
3039 {
3040  	unsigned long flags;
3041 	int rc;
3042 	struct mgsl_icount cprev, cnow;
3043 	DECLARE_WAITQUEUE(wait, current);
3044 
3045 	/* save current irq counts */
3046 	spin_lock_irqsave(&info->lock,flags);
3047 	cprev = info->icount;
3048 	add_wait_queue(&info->status_event_wait_q, &wait);
3049 	set_current_state(TASK_INTERRUPTIBLE);
3050 	spin_unlock_irqrestore(&info->lock,flags);
3051 
3052 	for(;;) {
3053 		schedule();
3054 		if (signal_pending(current)) {
3055 			rc = -ERESTARTSYS;
3056 			break;
3057 		}
3058 
3059 		/* get new irq counts */
3060 		spin_lock_irqsave(&info->lock,flags);
3061 		cnow = info->icount;
3062 		set_current_state(TASK_INTERRUPTIBLE);
3063 		spin_unlock_irqrestore(&info->lock,flags);
3064 
3065 		/* if no change, wait aborted for some reason */
3066 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3067 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3068 			rc = -EIO;
3069 			break;
3070 		}
3071 
3072 		/* check for change in caller specified modem input */
3073 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3074 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3075 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3076 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3077 			rc = 0;
3078 			break;
3079 		}
3080 
3081 		cprev = cnow;
3082 	}
3083 	remove_wait_queue(&info->status_event_wait_q, &wait);
3084 	set_current_state(TASK_RUNNING);
3085 	return rc;
3086 }
3087 
3088 /*
3089  *  return state of serial control and status signals
3090  */
3091 static int tiocmget(struct tty_struct *tty)
3092 {
3093 	struct slgt_info *info = tty->driver_data;
3094 	unsigned int result;
3095  	unsigned long flags;
3096 
3097 	spin_lock_irqsave(&info->lock,flags);
3098  	get_signals(info);
3099 	spin_unlock_irqrestore(&info->lock,flags);
3100 
3101 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3102 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3103 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3104 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3105 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3106 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3107 
3108 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3109 	return result;
3110 }
3111 
3112 /*
3113  * set modem control signals (DTR/RTS)
3114  *
3115  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3116  *		TIOCMSET = set/clear signal values
3117  * 	value	bit mask for command
3118  */
3119 static int tiocmset(struct tty_struct *tty,
3120 		    unsigned int set, unsigned int clear)
3121 {
3122 	struct slgt_info *info = tty->driver_data;
3123  	unsigned long flags;
3124 
3125 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3126 
3127 	if (set & TIOCM_RTS)
3128 		info->signals |= SerialSignal_RTS;
3129 	if (set & TIOCM_DTR)
3130 		info->signals |= SerialSignal_DTR;
3131 	if (clear & TIOCM_RTS)
3132 		info->signals &= ~SerialSignal_RTS;
3133 	if (clear & TIOCM_DTR)
3134 		info->signals &= ~SerialSignal_DTR;
3135 
3136 	spin_lock_irqsave(&info->lock,flags);
3137 	set_signals(info);
3138 	spin_unlock_irqrestore(&info->lock,flags);
3139 	return 0;
3140 }
3141 
3142 static int carrier_raised(struct tty_port *port)
3143 {
3144 	unsigned long flags;
3145 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3146 
3147 	spin_lock_irqsave(&info->lock,flags);
3148 	get_signals(info);
3149 	spin_unlock_irqrestore(&info->lock,flags);
3150 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3151 }
3152 
3153 static void dtr_rts(struct tty_port *port, int on)
3154 {
3155 	unsigned long flags;
3156 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3157 
3158 	spin_lock_irqsave(&info->lock,flags);
3159 	if (on)
3160 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3161 	else
3162 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3163 	set_signals(info);
3164 	spin_unlock_irqrestore(&info->lock,flags);
3165 }
3166 
3167 
3168 /*
3169  *  block current process until the device is ready to open
3170  */
3171 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3172 			   struct slgt_info *info)
3173 {
3174 	DECLARE_WAITQUEUE(wait, current);
3175 	int		retval;
3176 	bool		do_clocal = false;
3177 	unsigned long	flags;
3178 	int		cd;
3179 	struct tty_port *port = &info->port;
3180 
3181 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3182 
3183 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3184 		/* nonblock mode is set or port is not enabled */
3185 		tty_port_set_active(port, 1);
3186 		return 0;
3187 	}
3188 
3189 	if (C_CLOCAL(tty))
3190 		do_clocal = true;
3191 
3192 	/* Wait for carrier detect and the line to become
3193 	 * free (i.e., not in use by the callout).  While we are in
3194 	 * this loop, port->count is dropped by one, so that
3195 	 * close() knows when to free things.  We restore it upon
3196 	 * exit, either normal or abnormal.
3197 	 */
3198 
3199 	retval = 0;
3200 	add_wait_queue(&port->open_wait, &wait);
3201 
3202 	spin_lock_irqsave(&info->lock, flags);
3203 	port->count--;
3204 	spin_unlock_irqrestore(&info->lock, flags);
3205 	port->blocked_open++;
3206 
3207 	while (1) {
3208 		if (C_BAUD(tty) && tty_port_initialized(port))
3209 			tty_port_raise_dtr_rts(port);
3210 
3211 		set_current_state(TASK_INTERRUPTIBLE);
3212 
3213 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3214 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3215 					-EAGAIN : -ERESTARTSYS;
3216 			break;
3217 		}
3218 
3219 		cd = tty_port_carrier_raised(port);
3220 		if (do_clocal || cd)
3221 			break;
3222 
3223 		if (signal_pending(current)) {
3224 			retval = -ERESTARTSYS;
3225 			break;
3226 		}
3227 
3228 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3229 		tty_unlock(tty);
3230 		schedule();
3231 		tty_lock(tty);
3232 	}
3233 
3234 	set_current_state(TASK_RUNNING);
3235 	remove_wait_queue(&port->open_wait, &wait);
3236 
3237 	if (!tty_hung_up_p(filp))
3238 		port->count++;
3239 	port->blocked_open--;
3240 
3241 	if (!retval)
3242 		tty_port_set_active(port, 1);
3243 
3244 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3245 	return retval;
3246 }
3247 
3248 /*
3249  * allocate buffers used for calling line discipline receive_buf
3250  * directly in synchronous mode
3251  * note: add 5 bytes to max frame size to allow appending
3252  * 32-bit CRC and status byte when configured to do so
3253  */
3254 static int alloc_tmp_rbuf(struct slgt_info *info)
3255 {
3256 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3257 	if (info->tmp_rbuf == NULL)
3258 		return -ENOMEM;
3259 	/* unused flag buffer to satisfy receive_buf calling interface */
3260 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3261 	if (!info->flag_buf) {
3262 		kfree(info->tmp_rbuf);
3263 		info->tmp_rbuf = NULL;
3264 		return -ENOMEM;
3265 	}
3266 	return 0;
3267 }
3268 
3269 static void free_tmp_rbuf(struct slgt_info *info)
3270 {
3271 	kfree(info->tmp_rbuf);
3272 	info->tmp_rbuf = NULL;
3273 	kfree(info->flag_buf);
3274 	info->flag_buf = NULL;
3275 }
3276 
3277 /*
3278  * allocate DMA descriptor lists.
3279  */
3280 static int alloc_desc(struct slgt_info *info)
3281 {
3282 	unsigned int i;
3283 	unsigned int pbufs;
3284 
3285 	/* allocate memory to hold descriptor lists */
3286 	info->bufs = dma_alloc_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3287 					&info->bufs_dma_addr, GFP_KERNEL);
3288 	if (info->bufs == NULL)
3289 		return -ENOMEM;
3290 
3291 	info->rbufs = (struct slgt_desc*)info->bufs;
3292 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3293 
3294 	pbufs = (unsigned int)info->bufs_dma_addr;
3295 
3296 	/*
3297 	 * Build circular lists of descriptors
3298 	 */
3299 
3300 	for (i=0; i < info->rbuf_count; i++) {
3301 		/* physical address of this descriptor */
3302 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3303 
3304 		/* physical address of next descriptor */
3305 		if (i == info->rbuf_count - 1)
3306 			info->rbufs[i].next = cpu_to_le32(pbufs);
3307 		else
3308 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3309 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3310 	}
3311 
3312 	for (i=0; i < info->tbuf_count; i++) {
3313 		/* physical address of this descriptor */
3314 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3315 
3316 		/* physical address of next descriptor */
3317 		if (i == info->tbuf_count - 1)
3318 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3319 		else
3320 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3321 	}
3322 
3323 	return 0;
3324 }
3325 
3326 static void free_desc(struct slgt_info *info)
3327 {
3328 	if (info->bufs != NULL) {
3329 		dma_free_coherent(&info->pdev->dev, DESC_LIST_SIZE,
3330 				  info->bufs, info->bufs_dma_addr);
3331 		info->bufs  = NULL;
3332 		info->rbufs = NULL;
3333 		info->tbufs = NULL;
3334 	}
3335 }
3336 
3337 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3338 {
3339 	int i;
3340 	for (i=0; i < count; i++) {
3341 		bufs[i].buf = dma_alloc_coherent(&info->pdev->dev, DMABUFSIZE,
3342 						 &bufs[i].buf_dma_addr, GFP_KERNEL);
3343 		if (!bufs[i].buf)
3344 			return -ENOMEM;
3345 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3346 	}
3347 	return 0;
3348 }
3349 
3350 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3351 {
3352 	int i;
3353 	for (i=0; i < count; i++) {
3354 		if (bufs[i].buf == NULL)
3355 			continue;
3356 		dma_free_coherent(&info->pdev->dev, DMABUFSIZE, bufs[i].buf,
3357 				  bufs[i].buf_dma_addr);
3358 		bufs[i].buf = NULL;
3359 	}
3360 }
3361 
3362 static int alloc_dma_bufs(struct slgt_info *info)
3363 {
3364 	info->rbuf_count = 32;
3365 	info->tbuf_count = 32;
3366 
3367 	if (alloc_desc(info) < 0 ||
3368 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3369 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3370 	    alloc_tmp_rbuf(info) < 0) {
3371 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3372 		return -ENOMEM;
3373 	}
3374 	reset_rbufs(info);
3375 	return 0;
3376 }
3377 
3378 static void free_dma_bufs(struct slgt_info *info)
3379 {
3380 	if (info->bufs) {
3381 		free_bufs(info, info->rbufs, info->rbuf_count);
3382 		free_bufs(info, info->tbufs, info->tbuf_count);
3383 		free_desc(info);
3384 	}
3385 	free_tmp_rbuf(info);
3386 }
3387 
3388 static int claim_resources(struct slgt_info *info)
3389 {
3390 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3391 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3392 			info->device_name, info->phys_reg_addr));
3393 		info->init_error = DiagStatus_AddressConflict;
3394 		goto errout;
3395 	}
3396 	else
3397 		info->reg_addr_requested = true;
3398 
3399 	info->reg_addr = ioremap(info->phys_reg_addr, SLGT_REG_SIZE);
3400 	if (!info->reg_addr) {
3401 		DBGERR(("%s can't map device registers, addr=%08X\n",
3402 			info->device_name, info->phys_reg_addr));
3403 		info->init_error = DiagStatus_CantAssignPciResources;
3404 		goto errout;
3405 	}
3406 	return 0;
3407 
3408 errout:
3409 	release_resources(info);
3410 	return -ENODEV;
3411 }
3412 
3413 static void release_resources(struct slgt_info *info)
3414 {
3415 	if (info->irq_requested) {
3416 		free_irq(info->irq_level, info);
3417 		info->irq_requested = false;
3418 	}
3419 
3420 	if (info->reg_addr_requested) {
3421 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3422 		info->reg_addr_requested = false;
3423 	}
3424 
3425 	if (info->reg_addr) {
3426 		iounmap(info->reg_addr);
3427 		info->reg_addr = NULL;
3428 	}
3429 }
3430 
3431 /* Add the specified device instance data structure to the
3432  * global linked list of devices and increment the device count.
3433  */
3434 static void add_device(struct slgt_info *info)
3435 {
3436 	char *devstr;
3437 
3438 	info->next_device = NULL;
3439 	info->line = slgt_device_count;
3440 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3441 
3442 	if (info->line < MAX_DEVICES) {
3443 		if (maxframe[info->line])
3444 			info->max_frame_size = maxframe[info->line];
3445 	}
3446 
3447 	slgt_device_count++;
3448 
3449 	if (!slgt_device_list)
3450 		slgt_device_list = info;
3451 	else {
3452 		struct slgt_info *current_dev = slgt_device_list;
3453 		while(current_dev->next_device)
3454 			current_dev = current_dev->next_device;
3455 		current_dev->next_device = info;
3456 	}
3457 
3458 	if (info->max_frame_size < 4096)
3459 		info->max_frame_size = 4096;
3460 	else if (info->max_frame_size > 65535)
3461 		info->max_frame_size = 65535;
3462 
3463 	switch(info->pdev->device) {
3464 	case SYNCLINK_GT_DEVICE_ID:
3465 		devstr = "GT";
3466 		break;
3467 	case SYNCLINK_GT2_DEVICE_ID:
3468 		devstr = "GT2";
3469 		break;
3470 	case SYNCLINK_GT4_DEVICE_ID:
3471 		devstr = "GT4";
3472 		break;
3473 	case SYNCLINK_AC_DEVICE_ID:
3474 		devstr = "AC";
3475 		info->params.mode = MGSL_MODE_ASYNC;
3476 		break;
3477 	default:
3478 		devstr = "(unknown model)";
3479 	}
3480 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3481 		devstr, info->device_name, info->phys_reg_addr,
3482 		info->irq_level, info->max_frame_size);
3483 
3484 #if SYNCLINK_GENERIC_HDLC
3485 	hdlcdev_init(info);
3486 #endif
3487 }
3488 
3489 static const struct tty_port_operations slgt_port_ops = {
3490 	.carrier_raised = carrier_raised,
3491 	.dtr_rts = dtr_rts,
3492 };
3493 
3494 /*
3495  *  allocate device instance structure, return NULL on failure
3496  */
3497 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3498 {
3499 	struct slgt_info *info;
3500 
3501 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3502 
3503 	if (!info) {
3504 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3505 			driver_name, adapter_num, port_num));
3506 	} else {
3507 		tty_port_init(&info->port);
3508 		info->port.ops = &slgt_port_ops;
3509 		info->magic = MGSL_MAGIC;
3510 		INIT_WORK(&info->task, bh_handler);
3511 		info->max_frame_size = 4096;
3512 		info->base_clock = 14745600;
3513 		info->rbuf_fill_level = DMABUFSIZE;
3514 		init_waitqueue_head(&info->status_event_wait_q);
3515 		init_waitqueue_head(&info->event_wait_q);
3516 		spin_lock_init(&info->netlock);
3517 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3518 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3519 		info->adapter_num = adapter_num;
3520 		info->port_num = port_num;
3521 
3522 		timer_setup(&info->tx_timer, tx_timeout, 0);
3523 		timer_setup(&info->rx_timer, rx_timeout, 0);
3524 
3525 		/* Copy configuration info to device instance data */
3526 		info->pdev = pdev;
3527 		info->irq_level = pdev->irq;
3528 		info->phys_reg_addr = pci_resource_start(pdev,0);
3529 
3530 		info->bus_type = MGSL_BUS_TYPE_PCI;
3531 		info->irq_flags = IRQF_SHARED;
3532 
3533 		info->init_error = -1; /* assume error, set to 0 on successful init */
3534 	}
3535 
3536 	return info;
3537 }
3538 
3539 static void device_init(int adapter_num, struct pci_dev *pdev)
3540 {
3541 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3542 	int i;
3543 	int port_count = 1;
3544 
3545 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3546 		port_count = 2;
3547 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3548 		port_count = 4;
3549 
3550 	/* allocate device instances for all ports */
3551 	for (i=0; i < port_count; ++i) {
3552 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3553 		if (port_array[i] == NULL) {
3554 			for (--i; i >= 0; --i) {
3555 				tty_port_destroy(&port_array[i]->port);
3556 				kfree(port_array[i]);
3557 			}
3558 			return;
3559 		}
3560 	}
3561 
3562 	/* give copy of port_array to all ports and add to device list  */
3563 	for (i=0; i < port_count; ++i) {
3564 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3565 		add_device(port_array[i]);
3566 		port_array[i]->port_count = port_count;
3567 		spin_lock_init(&port_array[i]->lock);
3568 	}
3569 
3570 	/* Allocate and claim adapter resources */
3571 	if (!claim_resources(port_array[0])) {
3572 
3573 		alloc_dma_bufs(port_array[0]);
3574 
3575 		/* copy resource information from first port to others */
3576 		for (i = 1; i < port_count; ++i) {
3577 			port_array[i]->irq_level = port_array[0]->irq_level;
3578 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3579 			alloc_dma_bufs(port_array[i]);
3580 		}
3581 
3582 		if (request_irq(port_array[0]->irq_level,
3583 					slgt_interrupt,
3584 					port_array[0]->irq_flags,
3585 					port_array[0]->device_name,
3586 					port_array[0]) < 0) {
3587 			DBGERR(("%s request_irq failed IRQ=%d\n",
3588 				port_array[0]->device_name,
3589 				port_array[0]->irq_level));
3590 		} else {
3591 			port_array[0]->irq_requested = true;
3592 			adapter_test(port_array[0]);
3593 			for (i=1 ; i < port_count ; i++) {
3594 				port_array[i]->init_error = port_array[0]->init_error;
3595 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3596 			}
3597 		}
3598 	}
3599 
3600 	for (i = 0; i < port_count; ++i) {
3601 		struct slgt_info *info = port_array[i];
3602 		tty_port_register_device(&info->port, serial_driver, info->line,
3603 				&info->pdev->dev);
3604 	}
3605 }
3606 
3607 static int init_one(struct pci_dev *dev,
3608 			      const struct pci_device_id *ent)
3609 {
3610 	if (pci_enable_device(dev)) {
3611 		printk("error enabling pci device %p\n", dev);
3612 		return -EIO;
3613 	}
3614 	pci_set_master(dev);
3615 	device_init(slgt_device_count, dev);
3616 	return 0;
3617 }
3618 
3619 static void remove_one(struct pci_dev *dev)
3620 {
3621 }
3622 
3623 static const struct tty_operations ops = {
3624 	.open = open,
3625 	.close = close,
3626 	.write = write,
3627 	.put_char = put_char,
3628 	.flush_chars = flush_chars,
3629 	.write_room = write_room,
3630 	.chars_in_buffer = chars_in_buffer,
3631 	.flush_buffer = flush_buffer,
3632 	.ioctl = ioctl,
3633 	.compat_ioctl = slgt_compat_ioctl,
3634 	.throttle = throttle,
3635 	.unthrottle = unthrottle,
3636 	.send_xchar = send_xchar,
3637 	.break_ctl = set_break,
3638 	.wait_until_sent = wait_until_sent,
3639 	.set_termios = set_termios,
3640 	.stop = tx_hold,
3641 	.start = tx_release,
3642 	.hangup = hangup,
3643 	.tiocmget = tiocmget,
3644 	.tiocmset = tiocmset,
3645 	.get_icount = get_icount,
3646 	.proc_show = synclink_gt_proc_show,
3647 };
3648 
3649 static void slgt_cleanup(void)
3650 {
3651 	struct slgt_info *info;
3652 	struct slgt_info *tmp;
3653 
3654 	printk(KERN_INFO "unload %s\n", driver_name);
3655 
3656 	if (serial_driver) {
3657 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3658 			tty_unregister_device(serial_driver, info->line);
3659 		tty_unregister_driver(serial_driver);
3660 		put_tty_driver(serial_driver);
3661 	}
3662 
3663 	/* reset devices */
3664 	info = slgt_device_list;
3665 	while(info) {
3666 		reset_port(info);
3667 		info = info->next_device;
3668 	}
3669 
3670 	/* release devices */
3671 	info = slgt_device_list;
3672 	while(info) {
3673 #if SYNCLINK_GENERIC_HDLC
3674 		hdlcdev_exit(info);
3675 #endif
3676 		free_dma_bufs(info);
3677 		free_tmp_rbuf(info);
3678 		if (info->port_num == 0)
3679 			release_resources(info);
3680 		tmp = info;
3681 		info = info->next_device;
3682 		tty_port_destroy(&tmp->port);
3683 		kfree(tmp);
3684 	}
3685 
3686 	if (pci_registered)
3687 		pci_unregister_driver(&pci_driver);
3688 }
3689 
3690 /*
3691  *  Driver initialization entry point.
3692  */
3693 static int __init slgt_init(void)
3694 {
3695 	int rc;
3696 
3697 	printk(KERN_INFO "%s\n", driver_name);
3698 
3699 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3700 	if (!serial_driver) {
3701 		printk("%s can't allocate tty driver\n", driver_name);
3702 		return -ENOMEM;
3703 	}
3704 
3705 	/* Initialize the tty_driver structure */
3706 
3707 	serial_driver->driver_name = slgt_driver_name;
3708 	serial_driver->name = tty_dev_prefix;
3709 	serial_driver->major = ttymajor;
3710 	serial_driver->minor_start = 64;
3711 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3712 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3713 	serial_driver->init_termios = tty_std_termios;
3714 	serial_driver->init_termios.c_cflag =
3715 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3716 	serial_driver->init_termios.c_ispeed = 9600;
3717 	serial_driver->init_termios.c_ospeed = 9600;
3718 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3719 	tty_set_operations(serial_driver, &ops);
3720 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3721 		DBGERR(("%s can't register serial driver\n", driver_name));
3722 		put_tty_driver(serial_driver);
3723 		serial_driver = NULL;
3724 		goto error;
3725 	}
3726 
3727 	printk(KERN_INFO "%s, tty major#%d\n",
3728 	       driver_name, serial_driver->major);
3729 
3730 	slgt_device_count = 0;
3731 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3732 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3733 		goto error;
3734 	}
3735 	pci_registered = true;
3736 
3737 	if (!slgt_device_list)
3738 		printk("%s no devices found\n",driver_name);
3739 
3740 	return 0;
3741 
3742 error:
3743 	slgt_cleanup();
3744 	return rc;
3745 }
3746 
3747 static void __exit slgt_exit(void)
3748 {
3749 	slgt_cleanup();
3750 }
3751 
3752 module_init(slgt_init);
3753 module_exit(slgt_exit);
3754 
3755 /*
3756  * register access routines
3757  */
3758 
3759 #define CALC_REGADDR() \
3760 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3761 	if (addr >= 0x80) \
3762 		reg_addr += (info->port_num) * 32; \
3763 	else if (addr >= 0x40)	\
3764 		reg_addr += (info->port_num) * 16;
3765 
3766 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3767 {
3768 	CALC_REGADDR();
3769 	return readb((void __iomem *)reg_addr);
3770 }
3771 
3772 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3773 {
3774 	CALC_REGADDR();
3775 	writeb(value, (void __iomem *)reg_addr);
3776 }
3777 
3778 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3779 {
3780 	CALC_REGADDR();
3781 	return readw((void __iomem *)reg_addr);
3782 }
3783 
3784 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3785 {
3786 	CALC_REGADDR();
3787 	writew(value, (void __iomem *)reg_addr);
3788 }
3789 
3790 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3791 {
3792 	CALC_REGADDR();
3793 	return readl((void __iomem *)reg_addr);
3794 }
3795 
3796 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3797 {
3798 	CALC_REGADDR();
3799 	writel(value, (void __iomem *)reg_addr);
3800 }
3801 
3802 static void rdma_reset(struct slgt_info *info)
3803 {
3804 	unsigned int i;
3805 
3806 	/* set reset bit */
3807 	wr_reg32(info, RDCSR, BIT1);
3808 
3809 	/* wait for enable bit cleared */
3810 	for(i=0 ; i < 1000 ; i++)
3811 		if (!(rd_reg32(info, RDCSR) & BIT0))
3812 			break;
3813 }
3814 
3815 static void tdma_reset(struct slgt_info *info)
3816 {
3817 	unsigned int i;
3818 
3819 	/* set reset bit */
3820 	wr_reg32(info, TDCSR, BIT1);
3821 
3822 	/* wait for enable bit cleared */
3823 	for(i=0 ; i < 1000 ; i++)
3824 		if (!(rd_reg32(info, TDCSR) & BIT0))
3825 			break;
3826 }
3827 
3828 /*
3829  * enable internal loopback
3830  * TxCLK and RxCLK are generated from BRG
3831  * and TxD is looped back to RxD internally.
3832  */
3833 static void enable_loopback(struct slgt_info *info)
3834 {
3835 	/* SCR (serial control) BIT2=loopback enable */
3836 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3837 
3838 	if (info->params.mode != MGSL_MODE_ASYNC) {
3839 		/* CCR (clock control)
3840 		 * 07..05  tx clock source (010 = BRG)
3841 		 * 04..02  rx clock source (010 = BRG)
3842 		 * 01      auxclk enable   (0 = disable)
3843 		 * 00      BRG enable      (1 = enable)
3844 		 *
3845 		 * 0100 1001
3846 		 */
3847 		wr_reg8(info, CCR, 0x49);
3848 
3849 		/* set speed if available, otherwise use default */
3850 		if (info->params.clock_speed)
3851 			set_rate(info, info->params.clock_speed);
3852 		else
3853 			set_rate(info, 3686400);
3854 	}
3855 }
3856 
3857 /*
3858  *  set baud rate generator to specified rate
3859  */
3860 static void set_rate(struct slgt_info *info, u32 rate)
3861 {
3862 	unsigned int div;
3863 	unsigned int osc = info->base_clock;
3864 
3865 	/* div = osc/rate - 1
3866 	 *
3867 	 * Round div up if osc/rate is not integer to
3868 	 * force to next slowest rate.
3869 	 */
3870 
3871 	if (rate) {
3872 		div = osc/rate;
3873 		if (!(osc % rate) && div)
3874 			div--;
3875 		wr_reg16(info, BDR, (unsigned short)div);
3876 	}
3877 }
3878 
3879 static void rx_stop(struct slgt_info *info)
3880 {
3881 	unsigned short val;
3882 
3883 	/* disable and reset receiver */
3884 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3885 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3886 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3887 
3888 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3889 
3890 	/* clear pending rx interrupts */
3891 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3892 
3893 	rdma_reset(info);
3894 
3895 	info->rx_enabled = false;
3896 	info->rx_restart = false;
3897 }
3898 
3899 static void rx_start(struct slgt_info *info)
3900 {
3901 	unsigned short val;
3902 
3903 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3904 
3905 	/* clear pending rx overrun IRQ */
3906 	wr_reg16(info, SSR, IRQ_RXOVER);
3907 
3908 	/* reset and disable receiver */
3909 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3910 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3911 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3912 
3913 	rdma_reset(info);
3914 	reset_rbufs(info);
3915 
3916 	if (info->rx_pio) {
3917 		/* rx request when rx FIFO not empty */
3918 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3919 		slgt_irq_on(info, IRQ_RXDATA);
3920 		if (info->params.mode == MGSL_MODE_ASYNC) {
3921 			/* enable saving of rx status */
3922 			wr_reg32(info, RDCSR, BIT6);
3923 		}
3924 	} else {
3925 		/* rx request when rx FIFO half full */
3926 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3927 		/* set 1st descriptor address */
3928 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3929 
3930 		if (info->params.mode != MGSL_MODE_ASYNC) {
3931 			/* enable rx DMA and DMA interrupt */
3932 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
3933 		} else {
3934 			/* enable saving of rx status, rx DMA and DMA interrupt */
3935 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
3936 		}
3937 	}
3938 
3939 	slgt_irq_on(info, IRQ_RXOVER);
3940 
3941 	/* enable receiver */
3942 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
3943 
3944 	info->rx_restart = false;
3945 	info->rx_enabled = true;
3946 }
3947 
3948 static void tx_start(struct slgt_info *info)
3949 {
3950 	if (!info->tx_enabled) {
3951 		wr_reg16(info, TCR,
3952 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
3953 		info->tx_enabled = true;
3954 	}
3955 
3956 	if (desc_count(info->tbufs[info->tbuf_start])) {
3957 		info->drop_rts_on_tx_done = false;
3958 
3959 		if (info->params.mode != MGSL_MODE_ASYNC) {
3960 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
3961 				get_signals(info);
3962 				if (!(info->signals & SerialSignal_RTS)) {
3963 					info->signals |= SerialSignal_RTS;
3964 					set_signals(info);
3965 					info->drop_rts_on_tx_done = true;
3966 				}
3967 			}
3968 
3969 			slgt_irq_off(info, IRQ_TXDATA);
3970 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
3971 			/* clear tx idle and underrun status bits */
3972 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
3973 		} else {
3974 			slgt_irq_off(info, IRQ_TXDATA);
3975 			slgt_irq_on(info, IRQ_TXIDLE);
3976 			/* clear tx idle status bit */
3977 			wr_reg16(info, SSR, IRQ_TXIDLE);
3978 		}
3979 		/* set 1st descriptor address and start DMA */
3980 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
3981 		wr_reg32(info, TDCSR, BIT2 + BIT0);
3982 		info->tx_active = true;
3983 	}
3984 }
3985 
3986 static void tx_stop(struct slgt_info *info)
3987 {
3988 	unsigned short val;
3989 
3990 	del_timer(&info->tx_timer);
3991 
3992 	tdma_reset(info);
3993 
3994 	/* reset and disable transmitter */
3995 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
3996 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
3997 
3998 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
3999 
4000 	/* clear tx idle and underrun status bit */
4001 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4002 
4003 	reset_tbufs(info);
4004 
4005 	info->tx_enabled = false;
4006 	info->tx_active = false;
4007 }
4008 
4009 static void reset_port(struct slgt_info *info)
4010 {
4011 	if (!info->reg_addr)
4012 		return;
4013 
4014 	tx_stop(info);
4015 	rx_stop(info);
4016 
4017 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4018 	set_signals(info);
4019 
4020 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4021 }
4022 
4023 static void reset_adapter(struct slgt_info *info)
4024 {
4025 	int i;
4026 	for (i=0; i < info->port_count; ++i) {
4027 		if (info->port_array[i])
4028 			reset_port(info->port_array[i]);
4029 	}
4030 }
4031 
4032 static void async_mode(struct slgt_info *info)
4033 {
4034   	unsigned short val;
4035 
4036 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4037 	tx_stop(info);
4038 	rx_stop(info);
4039 
4040 	/* TCR (tx control)
4041 	 *
4042 	 * 15..13  mode, 010=async
4043 	 * 12..10  encoding, 000=NRZ
4044 	 * 09      parity enable
4045 	 * 08      1=odd parity, 0=even parity
4046 	 * 07      1=RTS driver control
4047 	 * 06      1=break enable
4048 	 * 05..04  character length
4049 	 *         00=5 bits
4050 	 *         01=6 bits
4051 	 *         10=7 bits
4052 	 *         11=8 bits
4053 	 * 03      0=1 stop bit, 1=2 stop bits
4054 	 * 02      reset
4055 	 * 01      enable
4056 	 * 00      auto-CTS enable
4057 	 */
4058 	val = 0x4000;
4059 
4060 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4061 		val |= BIT7;
4062 
4063 	if (info->params.parity != ASYNC_PARITY_NONE) {
4064 		val |= BIT9;
4065 		if (info->params.parity == ASYNC_PARITY_ODD)
4066 			val |= BIT8;
4067 	}
4068 
4069 	switch (info->params.data_bits)
4070 	{
4071 	case 6: val |= BIT4; break;
4072 	case 7: val |= BIT5; break;
4073 	case 8: val |= BIT5 + BIT4; break;
4074 	}
4075 
4076 	if (info->params.stop_bits != 1)
4077 		val |= BIT3;
4078 
4079 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4080 		val |= BIT0;
4081 
4082 	wr_reg16(info, TCR, val);
4083 
4084 	/* RCR (rx control)
4085 	 *
4086 	 * 15..13  mode, 010=async
4087 	 * 12..10  encoding, 000=NRZ
4088 	 * 09      parity enable
4089 	 * 08      1=odd parity, 0=even parity
4090 	 * 07..06  reserved, must be 0
4091 	 * 05..04  character length
4092 	 *         00=5 bits
4093 	 *         01=6 bits
4094 	 *         10=7 bits
4095 	 *         11=8 bits
4096 	 * 03      reserved, must be zero
4097 	 * 02      reset
4098 	 * 01      enable
4099 	 * 00      auto-DCD enable
4100 	 */
4101 	val = 0x4000;
4102 
4103 	if (info->params.parity != ASYNC_PARITY_NONE) {
4104 		val |= BIT9;
4105 		if (info->params.parity == ASYNC_PARITY_ODD)
4106 			val |= BIT8;
4107 	}
4108 
4109 	switch (info->params.data_bits)
4110 	{
4111 	case 6: val |= BIT4; break;
4112 	case 7: val |= BIT5; break;
4113 	case 8: val |= BIT5 + BIT4; break;
4114 	}
4115 
4116 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4117 		val |= BIT0;
4118 
4119 	wr_reg16(info, RCR, val);
4120 
4121 	/* CCR (clock control)
4122 	 *
4123 	 * 07..05  011 = tx clock source is BRG/16
4124 	 * 04..02  010 = rx clock source is BRG
4125 	 * 01      0 = auxclk disabled
4126 	 * 00      1 = BRG enabled
4127 	 *
4128 	 * 0110 1001
4129 	 */
4130 	wr_reg8(info, CCR, 0x69);
4131 
4132 	msc_set_vcr(info);
4133 
4134 	/* SCR (serial control)
4135 	 *
4136 	 * 15  1=tx req on FIFO half empty
4137 	 * 14  1=rx req on FIFO half full
4138 	 * 13  tx data  IRQ enable
4139 	 * 12  tx idle  IRQ enable
4140 	 * 11  rx break on IRQ enable
4141 	 * 10  rx data  IRQ enable
4142 	 * 09  rx break off IRQ enable
4143 	 * 08  overrun  IRQ enable
4144 	 * 07  DSR      IRQ enable
4145 	 * 06  CTS      IRQ enable
4146 	 * 05  DCD      IRQ enable
4147 	 * 04  RI       IRQ enable
4148 	 * 03  0=16x sampling, 1=8x sampling
4149 	 * 02  1=txd->rxd internal loopback enable
4150 	 * 01  reserved, must be zero
4151 	 * 00  1=master IRQ enable
4152 	 */
4153 	val = BIT15 + BIT14 + BIT0;
4154 	/* JCR[8] : 1 = x8 async mode feature available */
4155 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4156 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4157 	     (info->base_clock % (info->params.data_rate * 16)))) {
4158 		/* use 8x sampling */
4159 		val |= BIT3;
4160 		set_rate(info, info->params.data_rate * 8);
4161 	} else {
4162 		/* use 16x sampling */
4163 		set_rate(info, info->params.data_rate * 16);
4164 	}
4165 	wr_reg16(info, SCR, val);
4166 
4167 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4168 
4169 	if (info->params.loopback)
4170 		enable_loopback(info);
4171 }
4172 
4173 static void sync_mode(struct slgt_info *info)
4174 {
4175 	unsigned short val;
4176 
4177 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4178 	tx_stop(info);
4179 	rx_stop(info);
4180 
4181 	/* TCR (tx control)
4182 	 *
4183 	 * 15..13  mode
4184 	 *         000=HDLC/SDLC
4185 	 *         001=raw bit synchronous
4186 	 *         010=asynchronous/isochronous
4187 	 *         011=monosync byte synchronous
4188 	 *         100=bisync byte synchronous
4189 	 *         101=xsync byte synchronous
4190 	 * 12..10  encoding
4191 	 * 09      CRC enable
4192 	 * 08      CRC32
4193 	 * 07      1=RTS driver control
4194 	 * 06      preamble enable
4195 	 * 05..04  preamble length
4196 	 * 03      share open/close flag
4197 	 * 02      reset
4198 	 * 01      enable
4199 	 * 00      auto-CTS enable
4200 	 */
4201 	val = BIT2;
4202 
4203 	switch(info->params.mode) {
4204 	case MGSL_MODE_XSYNC:
4205 		val |= BIT15 + BIT13;
4206 		break;
4207 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4208 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4209 	case MGSL_MODE_RAW:      val |= BIT13; break;
4210 	}
4211 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4212 		val |= BIT7;
4213 
4214 	switch(info->params.encoding)
4215 	{
4216 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4217 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4218 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4219 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4220 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4221 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4222 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4223 	}
4224 
4225 	switch (info->params.crc_type & HDLC_CRC_MASK)
4226 	{
4227 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4228 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4229 	}
4230 
4231 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4232 		val |= BIT6;
4233 
4234 	switch (info->params.preamble_length)
4235 	{
4236 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4237 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4238 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4239 	}
4240 
4241 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4242 		val |= BIT0;
4243 
4244 	wr_reg16(info, TCR, val);
4245 
4246 	/* TPR (transmit preamble) */
4247 
4248 	switch (info->params.preamble)
4249 	{
4250 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4251 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4252 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4253 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4254 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4255 	default:                          val = 0x7e; break;
4256 	}
4257 	wr_reg8(info, TPR, (unsigned char)val);
4258 
4259 	/* RCR (rx control)
4260 	 *
4261 	 * 15..13  mode
4262 	 *         000=HDLC/SDLC
4263 	 *         001=raw bit synchronous
4264 	 *         010=asynchronous/isochronous
4265 	 *         011=monosync byte synchronous
4266 	 *         100=bisync byte synchronous
4267 	 *         101=xsync byte synchronous
4268 	 * 12..10  encoding
4269 	 * 09      CRC enable
4270 	 * 08      CRC32
4271 	 * 07..03  reserved, must be 0
4272 	 * 02      reset
4273 	 * 01      enable
4274 	 * 00      auto-DCD enable
4275 	 */
4276 	val = 0;
4277 
4278 	switch(info->params.mode) {
4279 	case MGSL_MODE_XSYNC:
4280 		val |= BIT15 + BIT13;
4281 		break;
4282 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4283 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4284 	case MGSL_MODE_RAW:      val |= BIT13; break;
4285 	}
4286 
4287 	switch(info->params.encoding)
4288 	{
4289 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4290 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4291 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4292 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4293 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4294 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4295 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4296 	}
4297 
4298 	switch (info->params.crc_type & HDLC_CRC_MASK)
4299 	{
4300 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4301 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4302 	}
4303 
4304 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4305 		val |= BIT0;
4306 
4307 	wr_reg16(info, RCR, val);
4308 
4309 	/* CCR (clock control)
4310 	 *
4311 	 * 07..05  tx clock source
4312 	 * 04..02  rx clock source
4313 	 * 01      auxclk enable
4314 	 * 00      BRG enable
4315 	 */
4316 	val = 0;
4317 
4318 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4319 	{
4320 		// when RxC source is DPLL, BRG generates 16X DPLL
4321 		// reference clock, so take TxC from BRG/16 to get
4322 		// transmit clock at actual data rate
4323 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4324 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4325 		else
4326 			val |= BIT6;	/* 010, txclk = BRG */
4327 	}
4328 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4329 		val |= BIT7;	/* 100, txclk = DPLL Input */
4330 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4331 		val |= BIT5;	/* 001, txclk = RXC Input */
4332 
4333 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4334 		val |= BIT3;	/* 010, rxclk = BRG */
4335 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4336 		val |= BIT4;	/* 100, rxclk = DPLL */
4337 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4338 		val |= BIT2;	/* 001, rxclk = TXC Input */
4339 
4340 	if (info->params.clock_speed)
4341 		val |= BIT1 + BIT0;
4342 
4343 	wr_reg8(info, CCR, (unsigned char)val);
4344 
4345 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4346 	{
4347 		// program DPLL mode
4348 		switch(info->params.encoding)
4349 		{
4350 		case HDLC_ENCODING_BIPHASE_MARK:
4351 		case HDLC_ENCODING_BIPHASE_SPACE:
4352 			val = BIT7; break;
4353 		case HDLC_ENCODING_BIPHASE_LEVEL:
4354 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4355 			val = BIT7 + BIT6; break;
4356 		default: val = BIT6;	// NRZ encodings
4357 		}
4358 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4359 
4360 		// DPLL requires a 16X reference clock from BRG
4361 		set_rate(info, info->params.clock_speed * 16);
4362 	}
4363 	else
4364 		set_rate(info, info->params.clock_speed);
4365 
4366 	tx_set_idle(info);
4367 
4368 	msc_set_vcr(info);
4369 
4370 	/* SCR (serial control)
4371 	 *
4372 	 * 15  1=tx req on FIFO half empty
4373 	 * 14  1=rx req on FIFO half full
4374 	 * 13  tx data  IRQ enable
4375 	 * 12  tx idle  IRQ enable
4376 	 * 11  underrun IRQ enable
4377 	 * 10  rx data  IRQ enable
4378 	 * 09  rx idle  IRQ enable
4379 	 * 08  overrun  IRQ enable
4380 	 * 07  DSR      IRQ enable
4381 	 * 06  CTS      IRQ enable
4382 	 * 05  DCD      IRQ enable
4383 	 * 04  RI       IRQ enable
4384 	 * 03  reserved, must be zero
4385 	 * 02  1=txd->rxd internal loopback enable
4386 	 * 01  reserved, must be zero
4387 	 * 00  1=master IRQ enable
4388 	 */
4389 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4390 
4391 	if (info->params.loopback)
4392 		enable_loopback(info);
4393 }
4394 
4395 /*
4396  *  set transmit idle mode
4397  */
4398 static void tx_set_idle(struct slgt_info *info)
4399 {
4400 	unsigned char val;
4401 	unsigned short tcr;
4402 
4403 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4404 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4405 	 */
4406 	tcr = rd_reg16(info, TCR);
4407 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4408 		/* disable preamble, set idle size to 16 bits */
4409 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4410 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4411 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4412 	} else if (!(tcr & BIT6)) {
4413 		/* preamble is disabled, set idle size to 8 bits */
4414 		tcr &= ~(BIT5 + BIT4);
4415 	}
4416 	wr_reg16(info, TCR, tcr);
4417 
4418 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4419 		/* LSB of custom tx idle specified in tx idle register */
4420 		val = (unsigned char)(info->idle_mode & 0xff);
4421 	} else {
4422 		/* standard 8 bit idle patterns */
4423 		switch(info->idle_mode)
4424 		{
4425 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4426 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4427 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4428 		case HDLC_TXIDLE_ZEROS:
4429 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4430 		default:                         val = 0xff;
4431 		}
4432 	}
4433 
4434 	wr_reg8(info, TIR, val);
4435 }
4436 
4437 /*
4438  * get state of V24 status (input) signals
4439  */
4440 static void get_signals(struct slgt_info *info)
4441 {
4442 	unsigned short status = rd_reg16(info, SSR);
4443 
4444 	/* clear all serial signals except RTS and DTR */
4445 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4446 
4447 	if (status & BIT3)
4448 		info->signals |= SerialSignal_DSR;
4449 	if (status & BIT2)
4450 		info->signals |= SerialSignal_CTS;
4451 	if (status & BIT1)
4452 		info->signals |= SerialSignal_DCD;
4453 	if (status & BIT0)
4454 		info->signals |= SerialSignal_RI;
4455 }
4456 
4457 /*
4458  * set V.24 Control Register based on current configuration
4459  */
4460 static void msc_set_vcr(struct slgt_info *info)
4461 {
4462 	unsigned char val = 0;
4463 
4464 	/* VCR (V.24 control)
4465 	 *
4466 	 * 07..04  serial IF select
4467 	 * 03      DTR
4468 	 * 02      RTS
4469 	 * 01      LL
4470 	 * 00      RL
4471 	 */
4472 
4473 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4474 	{
4475 	case MGSL_INTERFACE_RS232:
4476 		val |= BIT5; /* 0010 */
4477 		break;
4478 	case MGSL_INTERFACE_V35:
4479 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4480 		break;
4481 	case MGSL_INTERFACE_RS422:
4482 		val |= BIT6; /* 0100 */
4483 		break;
4484 	}
4485 
4486 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4487 		val |= BIT4;
4488 	if (info->signals & SerialSignal_DTR)
4489 		val |= BIT3;
4490 	if (info->signals & SerialSignal_RTS)
4491 		val |= BIT2;
4492 	if (info->if_mode & MGSL_INTERFACE_LL)
4493 		val |= BIT1;
4494 	if (info->if_mode & MGSL_INTERFACE_RL)
4495 		val |= BIT0;
4496 	wr_reg8(info, VCR, val);
4497 }
4498 
4499 /*
4500  * set state of V24 control (output) signals
4501  */
4502 static void set_signals(struct slgt_info *info)
4503 {
4504 	unsigned char val = rd_reg8(info, VCR);
4505 	if (info->signals & SerialSignal_DTR)
4506 		val |= BIT3;
4507 	else
4508 		val &= ~BIT3;
4509 	if (info->signals & SerialSignal_RTS)
4510 		val |= BIT2;
4511 	else
4512 		val &= ~BIT2;
4513 	wr_reg8(info, VCR, val);
4514 }
4515 
4516 /*
4517  * free range of receive DMA buffers (i to last)
4518  */
4519 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4520 {
4521 	int done = 0;
4522 
4523 	while(!done) {
4524 		/* reset current buffer for reuse */
4525 		info->rbufs[i].status = 0;
4526 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4527 		if (i == last)
4528 			done = 1;
4529 		if (++i == info->rbuf_count)
4530 			i = 0;
4531 	}
4532 	info->rbuf_current = i;
4533 }
4534 
4535 /*
4536  * mark all receive DMA buffers as free
4537  */
4538 static void reset_rbufs(struct slgt_info *info)
4539 {
4540 	free_rbufs(info, 0, info->rbuf_count - 1);
4541 	info->rbuf_fill_index = 0;
4542 	info->rbuf_fill_count = 0;
4543 }
4544 
4545 /*
4546  * pass receive HDLC frame to upper layer
4547  *
4548  * return true if frame available, otherwise false
4549  */
4550 static bool rx_get_frame(struct slgt_info *info)
4551 {
4552 	unsigned int start, end;
4553 	unsigned short status;
4554 	unsigned int framesize = 0;
4555 	unsigned long flags;
4556 	struct tty_struct *tty = info->port.tty;
4557 	unsigned char addr_field = 0xff;
4558 	unsigned int crc_size = 0;
4559 
4560 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4561 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4562 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4563 	}
4564 
4565 check_again:
4566 
4567 	framesize = 0;
4568 	addr_field = 0xff;
4569 	start = end = info->rbuf_current;
4570 
4571 	for (;;) {
4572 		if (!desc_complete(info->rbufs[end]))
4573 			goto cleanup;
4574 
4575 		if (framesize == 0 && info->params.addr_filter != 0xff)
4576 			addr_field = info->rbufs[end].buf[0];
4577 
4578 		framesize += desc_count(info->rbufs[end]);
4579 
4580 		if (desc_eof(info->rbufs[end]))
4581 			break;
4582 
4583 		if (++end == info->rbuf_count)
4584 			end = 0;
4585 
4586 		if (end == info->rbuf_current) {
4587 			if (info->rx_enabled){
4588 				spin_lock_irqsave(&info->lock,flags);
4589 				rx_start(info);
4590 				spin_unlock_irqrestore(&info->lock,flags);
4591 			}
4592 			goto cleanup;
4593 		}
4594 	}
4595 
4596 	/* status
4597 	 *
4598 	 * 15      buffer complete
4599 	 * 14..06  reserved
4600 	 * 05..04  residue
4601 	 * 02      eof (end of frame)
4602 	 * 01      CRC error
4603 	 * 00      abort
4604 	 */
4605 	status = desc_status(info->rbufs[end]);
4606 
4607 	/* ignore CRC bit if not using CRC (bit is undefined) */
4608 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4609 		status &= ~BIT1;
4610 
4611 	if (framesize == 0 ||
4612 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4613 		free_rbufs(info, start, end);
4614 		goto check_again;
4615 	}
4616 
4617 	if (framesize < (2 + crc_size) || status & BIT0) {
4618 		info->icount.rxshort++;
4619 		framesize = 0;
4620 	} else if (status & BIT1) {
4621 		info->icount.rxcrc++;
4622 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4623 			framesize = 0;
4624 	}
4625 
4626 #if SYNCLINK_GENERIC_HDLC
4627 	if (framesize == 0) {
4628 		info->netdev->stats.rx_errors++;
4629 		info->netdev->stats.rx_frame_errors++;
4630 	}
4631 #endif
4632 
4633 	DBGBH(("%s rx frame status=%04X size=%d\n",
4634 		info->device_name, status, framesize));
4635 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4636 
4637 	if (framesize) {
4638 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4639 			framesize -= crc_size;
4640 			crc_size = 0;
4641 		}
4642 
4643 		if (framesize > info->max_frame_size + crc_size)
4644 			info->icount.rxlong++;
4645 		else {
4646 			/* copy dma buffer(s) to contiguous temp buffer */
4647 			int copy_count = framesize;
4648 			int i = start;
4649 			unsigned char *p = info->tmp_rbuf;
4650 			info->tmp_rbuf_count = framesize;
4651 
4652 			info->icount.rxok++;
4653 
4654 			while(copy_count) {
4655 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4656 				memcpy(p, info->rbufs[i].buf, partial_count);
4657 				p += partial_count;
4658 				copy_count -= partial_count;
4659 				if (++i == info->rbuf_count)
4660 					i = 0;
4661 			}
4662 
4663 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4664 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4665 				framesize++;
4666 			}
4667 
4668 #if SYNCLINK_GENERIC_HDLC
4669 			if (info->netcount)
4670 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4671 			else
4672 #endif
4673 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4674 		}
4675 	}
4676 	free_rbufs(info, start, end);
4677 	return true;
4678 
4679 cleanup:
4680 	return false;
4681 }
4682 
4683 /*
4684  * pass receive buffer (RAW synchronous mode) to tty layer
4685  * return true if buffer available, otherwise false
4686  */
4687 static bool rx_get_buf(struct slgt_info *info)
4688 {
4689 	unsigned int i = info->rbuf_current;
4690 	unsigned int count;
4691 
4692 	if (!desc_complete(info->rbufs[i]))
4693 		return false;
4694 	count = desc_count(info->rbufs[i]);
4695 	switch(info->params.mode) {
4696 	case MGSL_MODE_MONOSYNC:
4697 	case MGSL_MODE_BISYNC:
4698 	case MGSL_MODE_XSYNC:
4699 		/* ignore residue in byte synchronous modes */
4700 		if (desc_residue(info->rbufs[i]))
4701 			count--;
4702 		break;
4703 	}
4704 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4705 	DBGINFO(("rx_get_buf size=%d\n", count));
4706 	if (count)
4707 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4708 				  info->flag_buf, count);
4709 	free_rbufs(info, i, i);
4710 	return true;
4711 }
4712 
4713 static void reset_tbufs(struct slgt_info *info)
4714 {
4715 	unsigned int i;
4716 	info->tbuf_current = 0;
4717 	for (i=0 ; i < info->tbuf_count ; i++) {
4718 		info->tbufs[i].status = 0;
4719 		info->tbufs[i].count  = 0;
4720 	}
4721 }
4722 
4723 /*
4724  * return number of free transmit DMA buffers
4725  */
4726 static unsigned int free_tbuf_count(struct slgt_info *info)
4727 {
4728 	unsigned int count = 0;
4729 	unsigned int i = info->tbuf_current;
4730 
4731 	do
4732 	{
4733 		if (desc_count(info->tbufs[i]))
4734 			break; /* buffer in use */
4735 		++count;
4736 		if (++i == info->tbuf_count)
4737 			i=0;
4738 	} while (i != info->tbuf_current);
4739 
4740 	/* if tx DMA active, last zero count buffer is in use */
4741 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4742 		--count;
4743 
4744 	return count;
4745 }
4746 
4747 /*
4748  * return number of bytes in unsent transmit DMA buffers
4749  * and the serial controller tx FIFO
4750  */
4751 static unsigned int tbuf_bytes(struct slgt_info *info)
4752 {
4753 	unsigned int total_count = 0;
4754 	unsigned int i = info->tbuf_current;
4755 	unsigned int reg_value;
4756 	unsigned int count;
4757 	unsigned int active_buf_count = 0;
4758 
4759 	/*
4760 	 * Add descriptor counts for all tx DMA buffers.
4761 	 * If count is zero (cleared by DMA controller after read),
4762 	 * the buffer is complete or is actively being read from.
4763 	 *
4764 	 * Record buf_count of last buffer with zero count starting
4765 	 * from current ring position. buf_count is mirror
4766 	 * copy of count and is not cleared by serial controller.
4767 	 * If DMA controller is active, that buffer is actively
4768 	 * being read so add to total.
4769 	 */
4770 	do {
4771 		count = desc_count(info->tbufs[i]);
4772 		if (count)
4773 			total_count += count;
4774 		else if (!total_count)
4775 			active_buf_count = info->tbufs[i].buf_count;
4776 		if (++i == info->tbuf_count)
4777 			i = 0;
4778 	} while (i != info->tbuf_current);
4779 
4780 	/* read tx DMA status register */
4781 	reg_value = rd_reg32(info, TDCSR);
4782 
4783 	/* if tx DMA active, last zero count buffer is in use */
4784 	if (reg_value & BIT0)
4785 		total_count += active_buf_count;
4786 
4787 	/* add tx FIFO count = reg_value[15..8] */
4788 	total_count += (reg_value >> 8) & 0xff;
4789 
4790 	/* if transmitter active add one byte for shift register */
4791 	if (info->tx_active)
4792 		total_count++;
4793 
4794 	return total_count;
4795 }
4796 
4797 /*
4798  * load data into transmit DMA buffer ring and start transmitter if needed
4799  * return true if data accepted, otherwise false (buffers full)
4800  */
4801 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4802 {
4803 	unsigned short count;
4804 	unsigned int i;
4805 	struct slgt_desc *d;
4806 
4807 	/* check required buffer space */
4808 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4809 		return false;
4810 
4811 	DBGDATA(info, buf, size, "tx");
4812 
4813 	/*
4814 	 * copy data to one or more DMA buffers in circular ring
4815 	 * tbuf_start   = first buffer for this data
4816 	 * tbuf_current = next free buffer
4817 	 *
4818 	 * Copy all data before making data visible to DMA controller by
4819 	 * setting descriptor count of the first buffer.
4820 	 * This prevents an active DMA controller from reading the first DMA
4821 	 * buffers of a frame and stopping before the final buffers are filled.
4822 	 */
4823 
4824 	info->tbuf_start = i = info->tbuf_current;
4825 
4826 	while (size) {
4827 		d = &info->tbufs[i];
4828 
4829 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4830 		memcpy(d->buf, buf, count);
4831 
4832 		size -= count;
4833 		buf  += count;
4834 
4835 		/*
4836 		 * set EOF bit for last buffer of HDLC frame or
4837 		 * for every buffer in raw mode
4838 		 */
4839 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4840 		    info->params.mode == MGSL_MODE_RAW)
4841 			set_desc_eof(*d, 1);
4842 		else
4843 			set_desc_eof(*d, 0);
4844 
4845 		/* set descriptor count for all but first buffer */
4846 		if (i != info->tbuf_start)
4847 			set_desc_count(*d, count);
4848 		d->buf_count = count;
4849 
4850 		if (++i == info->tbuf_count)
4851 			i = 0;
4852 	}
4853 
4854 	info->tbuf_current = i;
4855 
4856 	/* set first buffer count to make new data visible to DMA controller */
4857 	d = &info->tbufs[info->tbuf_start];
4858 	set_desc_count(*d, d->buf_count);
4859 
4860 	/* start transmitter if needed and update transmit timeout */
4861 	if (!info->tx_active)
4862 		tx_start(info);
4863 	update_tx_timer(info);
4864 
4865 	return true;
4866 }
4867 
4868 static int register_test(struct slgt_info *info)
4869 {
4870 	static unsigned short patterns[] =
4871 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4872 	static unsigned int count = ARRAY_SIZE(patterns);
4873 	unsigned int i;
4874 	int rc = 0;
4875 
4876 	for (i=0 ; i < count ; i++) {
4877 		wr_reg16(info, TIR, patterns[i]);
4878 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4879 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4880 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4881 			rc = -ENODEV;
4882 			break;
4883 		}
4884 	}
4885 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4886 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4887 	return rc;
4888 }
4889 
4890 static int irq_test(struct slgt_info *info)
4891 {
4892 	unsigned long timeout;
4893 	unsigned long flags;
4894 	struct tty_struct *oldtty = info->port.tty;
4895 	u32 speed = info->params.data_rate;
4896 
4897 	info->params.data_rate = 921600;
4898 	info->port.tty = NULL;
4899 
4900 	spin_lock_irqsave(&info->lock, flags);
4901 	async_mode(info);
4902 	slgt_irq_on(info, IRQ_TXIDLE);
4903 
4904 	/* enable transmitter */
4905 	wr_reg16(info, TCR,
4906 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4907 
4908 	/* write one byte and wait for tx idle */
4909 	wr_reg16(info, TDR, 0);
4910 
4911 	/* assume failure */
4912 	info->init_error = DiagStatus_IrqFailure;
4913 	info->irq_occurred = false;
4914 
4915 	spin_unlock_irqrestore(&info->lock, flags);
4916 
4917 	timeout=100;
4918 	while(timeout-- && !info->irq_occurred)
4919 		msleep_interruptible(10);
4920 
4921 	spin_lock_irqsave(&info->lock,flags);
4922 	reset_port(info);
4923 	spin_unlock_irqrestore(&info->lock,flags);
4924 
4925 	info->params.data_rate = speed;
4926 	info->port.tty = oldtty;
4927 
4928 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4929 	return info->irq_occurred ? 0 : -ENODEV;
4930 }
4931 
4932 static int loopback_test_rx(struct slgt_info *info)
4933 {
4934 	unsigned char *src, *dest;
4935 	int count;
4936 
4937 	if (desc_complete(info->rbufs[0])) {
4938 		count = desc_count(info->rbufs[0]);
4939 		src   = info->rbufs[0].buf;
4940 		dest  = info->tmp_rbuf;
4941 
4942 		for( ; count ; count-=2, src+=2) {
4943 			/* src=data byte (src+1)=status byte */
4944 			if (!(*(src+1) & (BIT9 + BIT8))) {
4945 				*dest = *src;
4946 				dest++;
4947 				info->tmp_rbuf_count++;
4948 			}
4949 		}
4950 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
4951 		return 1;
4952 	}
4953 	return 0;
4954 }
4955 
4956 static int loopback_test(struct slgt_info *info)
4957 {
4958 #define TESTFRAMESIZE 20
4959 
4960 	unsigned long timeout;
4961 	u16 count;
4962 	unsigned char buf[TESTFRAMESIZE];
4963 	int rc = -ENODEV;
4964 	unsigned long flags;
4965 
4966 	struct tty_struct *oldtty = info->port.tty;
4967 	MGSL_PARAMS params;
4968 
4969 	memcpy(&params, &info->params, sizeof(params));
4970 
4971 	info->params.mode = MGSL_MODE_ASYNC;
4972 	info->params.data_rate = 921600;
4973 	info->params.loopback = 1;
4974 	info->port.tty = NULL;
4975 
4976 	/* build and send transmit frame */
4977 	for (count = 0; count < TESTFRAMESIZE; ++count)
4978 		buf[count] = (unsigned char)count;
4979 
4980 	info->tmp_rbuf_count = 0;
4981 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
4982 
4983 	/* program hardware for HDLC and enabled receiver */
4984 	spin_lock_irqsave(&info->lock,flags);
4985 	async_mode(info);
4986 	rx_start(info);
4987 	tx_load(info, buf, count);
4988 	spin_unlock_irqrestore(&info->lock, flags);
4989 
4990 	/* wait for receive complete */
4991 	for (timeout = 100; timeout; --timeout) {
4992 		msleep_interruptible(10);
4993 		if (loopback_test_rx(info)) {
4994 			rc = 0;
4995 			break;
4996 		}
4997 	}
4998 
4999 	/* verify received frame length and contents */
5000 	if (!rc && (info->tmp_rbuf_count != count ||
5001 		  memcmp(buf, info->tmp_rbuf, count))) {
5002 		rc = -ENODEV;
5003 	}
5004 
5005 	spin_lock_irqsave(&info->lock,flags);
5006 	reset_adapter(info);
5007 	spin_unlock_irqrestore(&info->lock,flags);
5008 
5009 	memcpy(&info->params, &params, sizeof(info->params));
5010 	info->port.tty = oldtty;
5011 
5012 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5013 	return rc;
5014 }
5015 
5016 static int adapter_test(struct slgt_info *info)
5017 {
5018 	DBGINFO(("testing %s\n", info->device_name));
5019 	if (register_test(info) < 0) {
5020 		printk("register test failure %s addr=%08X\n",
5021 			info->device_name, info->phys_reg_addr);
5022 	} else if (irq_test(info) < 0) {
5023 		printk("IRQ test failure %s IRQ=%d\n",
5024 			info->device_name, info->irq_level);
5025 	} else if (loopback_test(info) < 0) {
5026 		printk("loopback test failure %s\n", info->device_name);
5027 	}
5028 	return info->init_error;
5029 }
5030 
5031 /*
5032  * transmit timeout handler
5033  */
5034 static void tx_timeout(struct timer_list *t)
5035 {
5036 	struct slgt_info *info = from_timer(info, t, tx_timer);
5037 	unsigned long flags;
5038 
5039 	DBGINFO(("%s tx_timeout\n", info->device_name));
5040 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5041 		info->icount.txtimeout++;
5042 	}
5043 	spin_lock_irqsave(&info->lock,flags);
5044 	tx_stop(info);
5045 	spin_unlock_irqrestore(&info->lock,flags);
5046 
5047 #if SYNCLINK_GENERIC_HDLC
5048 	if (info->netcount)
5049 		hdlcdev_tx_done(info);
5050 	else
5051 #endif
5052 		bh_transmit(info);
5053 }
5054 
5055 /*
5056  * receive buffer polling timer
5057  */
5058 static void rx_timeout(struct timer_list *t)
5059 {
5060 	struct slgt_info *info = from_timer(info, t, rx_timer);
5061 	unsigned long flags;
5062 
5063 	DBGINFO(("%s rx_timeout\n", info->device_name));
5064 	spin_lock_irqsave(&info->lock, flags);
5065 	info->pending_bh |= BH_RECEIVE;
5066 	spin_unlock_irqrestore(&info->lock, flags);
5067 	bh_handler(&info->task);
5068 }
5069 
5070