xref: /linux/drivers/tty/synclink_gt.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * Device driver for Microgate SyncLink GT serial adapters.
4  *
5  * written by Paul Fulghum for Microgate Corporation
6  * paulkf@microgate.com
7  *
8  * Microgate and SyncLink are trademarks of Microgate Corporation
9  *
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
11  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
12  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
14  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
15  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
18  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
19  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
20  * OF THE POSSIBILITY OF SUCH DAMAGE.
21  */
22 
23 /*
24  * DEBUG OUTPUT DEFINITIONS
25  *
26  * uncomment lines below to enable specific types of debug output
27  *
28  * DBGINFO   information - most verbose output
29  * DBGERR    serious errors
30  * DBGBH     bottom half service routine debugging
31  * DBGISR    interrupt service routine debugging
32  * DBGDATA   output receive and transmit data
33  * DBGTBUF   output transmit DMA buffers and registers
34  * DBGRBUF   output receive DMA buffers and registers
35  */
36 
37 #define DBGINFO(fmt) if (debug_level >= DEBUG_LEVEL_INFO) printk fmt
38 #define DBGERR(fmt) if (debug_level >= DEBUG_LEVEL_ERROR) printk fmt
39 #define DBGBH(fmt) if (debug_level >= DEBUG_LEVEL_BH) printk fmt
40 #define DBGISR(fmt) if (debug_level >= DEBUG_LEVEL_ISR) printk fmt
41 #define DBGDATA(info, buf, size, label) if (debug_level >= DEBUG_LEVEL_DATA) trace_block((info), (buf), (size), (label))
42 /*#define DBGTBUF(info) dump_tbufs(info)*/
43 /*#define DBGRBUF(info) dump_rbufs(info)*/
44 
45 
46 #include <linux/module.h>
47 #include <linux/errno.h>
48 #include <linux/signal.h>
49 #include <linux/sched.h>
50 #include <linux/timer.h>
51 #include <linux/interrupt.h>
52 #include <linux/pci.h>
53 #include <linux/tty.h>
54 #include <linux/tty_flip.h>
55 #include <linux/serial.h>
56 #include <linux/major.h>
57 #include <linux/string.h>
58 #include <linux/fcntl.h>
59 #include <linux/ptrace.h>
60 #include <linux/ioport.h>
61 #include <linux/mm.h>
62 #include <linux/seq_file.h>
63 #include <linux/slab.h>
64 #include <linux/netdevice.h>
65 #include <linux/vmalloc.h>
66 #include <linux/init.h>
67 #include <linux/delay.h>
68 #include <linux/ioctl.h>
69 #include <linux/termios.h>
70 #include <linux/bitops.h>
71 #include <linux/workqueue.h>
72 #include <linux/hdlc.h>
73 #include <linux/synclink.h>
74 
75 #include <asm/io.h>
76 #include <asm/irq.h>
77 #include <asm/dma.h>
78 #include <asm/types.h>
79 #include <linux/uaccess.h>
80 
81 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_GT_MODULE))
82 #define SYNCLINK_GENERIC_HDLC 1
83 #else
84 #define SYNCLINK_GENERIC_HDLC 0
85 #endif
86 
87 /*
88  * module identification
89  */
90 static char *driver_name     = "SyncLink GT";
91 static char *slgt_driver_name = "synclink_gt";
92 static char *tty_dev_prefix  = "ttySLG";
93 MODULE_LICENSE("GPL");
94 #define MGSL_MAGIC 0x5401
95 #define MAX_DEVICES 32
96 
97 static const struct pci_device_id pci_table[] = {
98 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
99 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT2_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
100 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_GT4_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
101 	{PCI_VENDOR_ID_MICROGATE, SYNCLINK_AC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
102 	{0,}, /* terminate list */
103 };
104 MODULE_DEVICE_TABLE(pci, pci_table);
105 
106 static int  init_one(struct pci_dev *dev,const struct pci_device_id *ent);
107 static void remove_one(struct pci_dev *dev);
108 static struct pci_driver pci_driver = {
109 	.name		= "synclink_gt",
110 	.id_table	= pci_table,
111 	.probe		= init_one,
112 	.remove		= remove_one,
113 };
114 
115 static bool pci_registered;
116 
117 /*
118  * module configuration and status
119  */
120 static struct slgt_info *slgt_device_list;
121 static int slgt_device_count;
122 
123 static int ttymajor;
124 static int debug_level;
125 static int maxframe[MAX_DEVICES];
126 
127 module_param(ttymajor, int, 0);
128 module_param(debug_level, int, 0);
129 module_param_array(maxframe, int, NULL, 0);
130 
131 MODULE_PARM_DESC(ttymajor, "TTY major device number override: 0=auto assigned");
132 MODULE_PARM_DESC(debug_level, "Debug syslog output: 0=disabled, 1 to 5=increasing detail");
133 MODULE_PARM_DESC(maxframe, "Maximum frame size used by device (4096 to 65535)");
134 
135 /*
136  * tty support and callbacks
137  */
138 static struct tty_driver *serial_driver;
139 
140 static int  open(struct tty_struct *tty, struct file * filp);
141 static void close(struct tty_struct *tty, struct file * filp);
142 static void hangup(struct tty_struct *tty);
143 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios);
144 
145 static int  write(struct tty_struct *tty, const unsigned char *buf, int count);
146 static int put_char(struct tty_struct *tty, unsigned char ch);
147 static void send_xchar(struct tty_struct *tty, char ch);
148 static void wait_until_sent(struct tty_struct *tty, int timeout);
149 static int  write_room(struct tty_struct *tty);
150 static void flush_chars(struct tty_struct *tty);
151 static void flush_buffer(struct tty_struct *tty);
152 static void tx_hold(struct tty_struct *tty);
153 static void tx_release(struct tty_struct *tty);
154 
155 static int  ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
156 static int  chars_in_buffer(struct tty_struct *tty);
157 static void throttle(struct tty_struct * tty);
158 static void unthrottle(struct tty_struct * tty);
159 static int set_break(struct tty_struct *tty, int break_state);
160 
161 /*
162  * generic HDLC support and callbacks
163  */
164 #if SYNCLINK_GENERIC_HDLC
165 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
166 static void hdlcdev_tx_done(struct slgt_info *info);
167 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size);
168 static int  hdlcdev_init(struct slgt_info *info);
169 static void hdlcdev_exit(struct slgt_info *info);
170 #endif
171 
172 
173 /*
174  * device specific structures, macros and functions
175  */
176 
177 #define SLGT_MAX_PORTS 4
178 #define SLGT_REG_SIZE  256
179 
180 /*
181  * conditional wait facility
182  */
183 struct cond_wait {
184 	struct cond_wait *next;
185 	wait_queue_head_t q;
186 	wait_queue_entry_t wait;
187 	unsigned int data;
188 };
189 static void init_cond_wait(struct cond_wait *w, unsigned int data);
190 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w);
191 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *w);
192 static void flush_cond_wait(struct cond_wait **head);
193 
194 /*
195  * DMA buffer descriptor and access macros
196  */
197 struct slgt_desc
198 {
199 	__le16 count;
200 	__le16 status;
201 	__le32 pbuf;  /* physical address of data buffer */
202 	__le32 next;  /* physical address of next descriptor */
203 
204 	/* driver book keeping */
205 	char *buf;          /* virtual  address of data buffer */
206     	unsigned int pdesc; /* physical address of this descriptor */
207 	dma_addr_t buf_dma_addr;
208 	unsigned short buf_count;
209 };
210 
211 #define set_desc_buffer(a,b) (a).pbuf = cpu_to_le32((unsigned int)(b))
212 #define set_desc_next(a,b) (a).next   = cpu_to_le32((unsigned int)(b))
213 #define set_desc_count(a,b)(a).count  = cpu_to_le16((unsigned short)(b))
214 #define set_desc_eof(a,b)  (a).status = cpu_to_le16((b) ? (le16_to_cpu((a).status) | BIT0) : (le16_to_cpu((a).status) & ~BIT0))
215 #define set_desc_status(a, b) (a).status = cpu_to_le16((unsigned short)(b))
216 #define desc_count(a)      (le16_to_cpu((a).count))
217 #define desc_status(a)     (le16_to_cpu((a).status))
218 #define desc_complete(a)   (le16_to_cpu((a).status) & BIT15)
219 #define desc_eof(a)        (le16_to_cpu((a).status) & BIT2)
220 #define desc_crc_error(a)  (le16_to_cpu((a).status) & BIT1)
221 #define desc_abort(a)      (le16_to_cpu((a).status) & BIT0)
222 #define desc_residue(a)    ((le16_to_cpu((a).status) & 0x38) >> 3)
223 
224 struct _input_signal_events {
225 	int ri_up;
226 	int ri_down;
227 	int dsr_up;
228 	int dsr_down;
229 	int dcd_up;
230 	int dcd_down;
231 	int cts_up;
232 	int cts_down;
233 };
234 
235 /*
236  * device instance data structure
237  */
238 struct slgt_info {
239 	void *if_ptr;		/* General purpose pointer (used by SPPP) */
240 	struct tty_port port;
241 
242 	struct slgt_info *next_device;	/* device list link */
243 
244 	int magic;
245 
246 	char device_name[25];
247 	struct pci_dev *pdev;
248 
249 	int port_count;  /* count of ports on adapter */
250 	int adapter_num; /* adapter instance number */
251 	int port_num;    /* port instance number */
252 
253 	/* array of pointers to port contexts on this adapter */
254 	struct slgt_info *port_array[SLGT_MAX_PORTS];
255 
256 	int			line;		/* tty line instance number */
257 
258 	struct mgsl_icount	icount;
259 
260 	int			timeout;
261 	int			x_char;		/* xon/xoff character */
262 	unsigned int		read_status_mask;
263 	unsigned int 		ignore_status_mask;
264 
265 	wait_queue_head_t	status_event_wait_q;
266 	wait_queue_head_t	event_wait_q;
267 	struct timer_list	tx_timer;
268 	struct timer_list	rx_timer;
269 
270 	unsigned int            gpio_present;
271 	struct cond_wait        *gpio_wait_q;
272 
273 	spinlock_t lock;	/* spinlock for synchronizing with ISR */
274 
275 	struct work_struct task;
276 	u32 pending_bh;
277 	bool bh_requested;
278 	bool bh_running;
279 
280 	int isr_overflow;
281 	bool irq_requested;	/* true if IRQ requested */
282 	bool irq_occurred;	/* for diagnostics use */
283 
284 	/* device configuration */
285 
286 	unsigned int bus_type;
287 	unsigned int irq_level;
288 	unsigned long irq_flags;
289 
290 	unsigned char __iomem * reg_addr;  /* memory mapped registers address */
291 	u32 phys_reg_addr;
292 	bool reg_addr_requested;
293 
294 	MGSL_PARAMS params;       /* communications parameters */
295 	u32 idle_mode;
296 	u32 max_frame_size;       /* as set by device config */
297 
298 	unsigned int rbuf_fill_level;
299 	unsigned int rx_pio;
300 	unsigned int if_mode;
301 	unsigned int base_clock;
302 	unsigned int xsync;
303 	unsigned int xctrl;
304 
305 	/* device status */
306 
307 	bool rx_enabled;
308 	bool rx_restart;
309 
310 	bool tx_enabled;
311 	bool tx_active;
312 
313 	unsigned char signals;    /* serial signal states */
314 	int init_error;  /* initialization error */
315 
316 	unsigned char *tx_buf;
317 	int tx_count;
318 
319 	char *flag_buf;
320 	bool drop_rts_on_tx_done;
321 	struct	_input_signal_events	input_signal_events;
322 
323 	int dcd_chkcount;	/* check counts to prevent */
324 	int cts_chkcount;	/* too many IRQs if a signal */
325 	int dsr_chkcount;	/* is floating */
326 	int ri_chkcount;
327 
328 	char *bufs;		/* virtual address of DMA buffer lists */
329 	dma_addr_t bufs_dma_addr; /* physical address of buffer descriptors */
330 
331 	unsigned int rbuf_count;
332 	struct slgt_desc *rbufs;
333 	unsigned int rbuf_current;
334 	unsigned int rbuf_index;
335 	unsigned int rbuf_fill_index;
336 	unsigned short rbuf_fill_count;
337 
338 	unsigned int tbuf_count;
339 	struct slgt_desc *tbufs;
340 	unsigned int tbuf_current;
341 	unsigned int tbuf_start;
342 
343 	unsigned char *tmp_rbuf;
344 	unsigned int tmp_rbuf_count;
345 
346 	/* SPPP/Cisco HDLC device parts */
347 
348 	int netcount;
349 	spinlock_t netlock;
350 #if SYNCLINK_GENERIC_HDLC
351 	struct net_device *netdev;
352 #endif
353 
354 };
355 
356 static MGSL_PARAMS default_params = {
357 	.mode            = MGSL_MODE_HDLC,
358 	.loopback        = 0,
359 	.flags           = HDLC_FLAG_UNDERRUN_ABORT15,
360 	.encoding        = HDLC_ENCODING_NRZI_SPACE,
361 	.clock_speed     = 0,
362 	.addr_filter     = 0xff,
363 	.crc_type        = HDLC_CRC_16_CCITT,
364 	.preamble_length = HDLC_PREAMBLE_LENGTH_8BITS,
365 	.preamble        = HDLC_PREAMBLE_PATTERN_NONE,
366 	.data_rate       = 9600,
367 	.data_bits       = 8,
368 	.stop_bits       = 1,
369 	.parity          = ASYNC_PARITY_NONE
370 };
371 
372 
373 #define BH_RECEIVE  1
374 #define BH_TRANSMIT 2
375 #define BH_STATUS   4
376 #define IO_PIN_SHUTDOWN_LIMIT 100
377 
378 #define DMABUFSIZE 256
379 #define DESC_LIST_SIZE 4096
380 
381 #define MASK_PARITY  BIT1
382 #define MASK_FRAMING BIT0
383 #define MASK_BREAK   BIT14
384 #define MASK_OVERRUN BIT4
385 
386 #define GSR   0x00 /* global status */
387 #define JCR   0x04 /* JTAG control */
388 #define IODR  0x08 /* GPIO direction */
389 #define IOER  0x0c /* GPIO interrupt enable */
390 #define IOVR  0x10 /* GPIO value */
391 #define IOSR  0x14 /* GPIO interrupt status */
392 #define TDR   0x80 /* tx data */
393 #define RDR   0x80 /* rx data */
394 #define TCR   0x82 /* tx control */
395 #define TIR   0x84 /* tx idle */
396 #define TPR   0x85 /* tx preamble */
397 #define RCR   0x86 /* rx control */
398 #define VCR   0x88 /* V.24 control */
399 #define CCR   0x89 /* clock control */
400 #define BDR   0x8a /* baud divisor */
401 #define SCR   0x8c /* serial control */
402 #define SSR   0x8e /* serial status */
403 #define RDCSR 0x90 /* rx DMA control/status */
404 #define TDCSR 0x94 /* tx DMA control/status */
405 #define RDDAR 0x98 /* rx DMA descriptor address */
406 #define TDDAR 0x9c /* tx DMA descriptor address */
407 #define XSR   0x40 /* extended sync pattern */
408 #define XCR   0x44 /* extended control */
409 
410 #define RXIDLE      BIT14
411 #define RXBREAK     BIT14
412 #define IRQ_TXDATA  BIT13
413 #define IRQ_TXIDLE  BIT12
414 #define IRQ_TXUNDER BIT11 /* HDLC */
415 #define IRQ_RXDATA  BIT10
416 #define IRQ_RXIDLE  BIT9  /* HDLC */
417 #define IRQ_RXBREAK BIT9  /* async */
418 #define IRQ_RXOVER  BIT8
419 #define IRQ_DSR     BIT7
420 #define IRQ_CTS     BIT6
421 #define IRQ_DCD     BIT5
422 #define IRQ_RI      BIT4
423 #define IRQ_ALL     0x3ff0
424 #define IRQ_MASTER  BIT0
425 
426 #define slgt_irq_on(info, mask) \
427 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) | (mask)))
428 #define slgt_irq_off(info, mask) \
429 	wr_reg16((info), SCR, (unsigned short)(rd_reg16((info), SCR) & ~(mask)))
430 
431 static __u8  rd_reg8(struct slgt_info *info, unsigned int addr);
432 static void  wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value);
433 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr);
434 static void  wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value);
435 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr);
436 static void  wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value);
437 
438 static void  msc_set_vcr(struct slgt_info *info);
439 
440 static int  startup(struct slgt_info *info);
441 static int  block_til_ready(struct tty_struct *tty, struct file * filp,struct slgt_info *info);
442 static void shutdown(struct slgt_info *info);
443 static void program_hw(struct slgt_info *info);
444 static void change_params(struct slgt_info *info);
445 
446 static int  register_test(struct slgt_info *info);
447 static int  irq_test(struct slgt_info *info);
448 static int  loopback_test(struct slgt_info *info);
449 static int  adapter_test(struct slgt_info *info);
450 
451 static void reset_adapter(struct slgt_info *info);
452 static void reset_port(struct slgt_info *info);
453 static void async_mode(struct slgt_info *info);
454 static void sync_mode(struct slgt_info *info);
455 
456 static void rx_stop(struct slgt_info *info);
457 static void rx_start(struct slgt_info *info);
458 static void reset_rbufs(struct slgt_info *info);
459 static void free_rbufs(struct slgt_info *info, unsigned int first, unsigned int last);
460 static void rdma_reset(struct slgt_info *info);
461 static bool rx_get_frame(struct slgt_info *info);
462 static bool rx_get_buf(struct slgt_info *info);
463 
464 static void tx_start(struct slgt_info *info);
465 static void tx_stop(struct slgt_info *info);
466 static void tx_set_idle(struct slgt_info *info);
467 static unsigned int free_tbuf_count(struct slgt_info *info);
468 static unsigned int tbuf_bytes(struct slgt_info *info);
469 static void reset_tbufs(struct slgt_info *info);
470 static void tdma_reset(struct slgt_info *info);
471 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int count);
472 
473 static void get_signals(struct slgt_info *info);
474 static void set_signals(struct slgt_info *info);
475 static void enable_loopback(struct slgt_info *info);
476 static void set_rate(struct slgt_info *info, u32 data_rate);
477 
478 static int  bh_action(struct slgt_info *info);
479 static void bh_handler(struct work_struct *work);
480 static void bh_transmit(struct slgt_info *info);
481 static void isr_serial(struct slgt_info *info);
482 static void isr_rdma(struct slgt_info *info);
483 static void isr_txeom(struct slgt_info *info, unsigned short status);
484 static void isr_tdma(struct slgt_info *info);
485 
486 static int  alloc_dma_bufs(struct slgt_info *info);
487 static void free_dma_bufs(struct slgt_info *info);
488 static int  alloc_desc(struct slgt_info *info);
489 static void free_desc(struct slgt_info *info);
490 static int  alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count);
491 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count);
492 
493 static int  alloc_tmp_rbuf(struct slgt_info *info);
494 static void free_tmp_rbuf(struct slgt_info *info);
495 
496 static void tx_timeout(struct timer_list *t);
497 static void rx_timeout(struct timer_list *t);
498 
499 /*
500  * ioctl handlers
501  */
502 static int  get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount);
503 static int  get_params(struct slgt_info *info, MGSL_PARAMS __user *params);
504 static int  set_params(struct slgt_info *info, MGSL_PARAMS __user *params);
505 static int  get_txidle(struct slgt_info *info, int __user *idle_mode);
506 static int  set_txidle(struct slgt_info *info, int idle_mode);
507 static int  tx_enable(struct slgt_info *info, int enable);
508 static int  tx_abort(struct slgt_info *info);
509 static int  rx_enable(struct slgt_info *info, int enable);
510 static int  modem_input_wait(struct slgt_info *info,int arg);
511 static int  wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr);
512 static int  tiocmget(struct tty_struct *tty);
513 static int  tiocmset(struct tty_struct *tty,
514 				unsigned int set, unsigned int clear);
515 static int set_break(struct tty_struct *tty, int break_state);
516 static int  get_interface(struct slgt_info *info, int __user *if_mode);
517 static int  set_interface(struct slgt_info *info, int if_mode);
518 static int  set_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
519 static int  get_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
520 static int  wait_gpio(struct slgt_info *info, struct gpio_desc __user *gpio);
521 static int  get_xsync(struct slgt_info *info, int __user *if_mode);
522 static int  set_xsync(struct slgt_info *info, int if_mode);
523 static int  get_xctrl(struct slgt_info *info, int __user *if_mode);
524 static int  set_xctrl(struct slgt_info *info, int if_mode);
525 
526 /*
527  * driver functions
528  */
529 static void add_device(struct slgt_info *info);
530 static void device_init(int adapter_num, struct pci_dev *pdev);
531 static int  claim_resources(struct slgt_info *info);
532 static void release_resources(struct slgt_info *info);
533 
534 /*
535  * DEBUG OUTPUT CODE
536  */
537 #ifndef DBGINFO
538 #define DBGINFO(fmt)
539 #endif
540 #ifndef DBGERR
541 #define DBGERR(fmt)
542 #endif
543 #ifndef DBGBH
544 #define DBGBH(fmt)
545 #endif
546 #ifndef DBGISR
547 #define DBGISR(fmt)
548 #endif
549 
550 #ifdef DBGDATA
551 static void trace_block(struct slgt_info *info, const char *data, int count, const char *label)
552 {
553 	int i;
554 	int linecount;
555 	printk("%s %s data:\n",info->device_name, label);
556 	while(count) {
557 		linecount = (count > 16) ? 16 : count;
558 		for(i=0; i < linecount; i++)
559 			printk("%02X ",(unsigned char)data[i]);
560 		for(;i<17;i++)
561 			printk("   ");
562 		for(i=0;i<linecount;i++) {
563 			if (data[i]>=040 && data[i]<=0176)
564 				printk("%c",data[i]);
565 			else
566 				printk(".");
567 		}
568 		printk("\n");
569 		data  += linecount;
570 		count -= linecount;
571 	}
572 }
573 #else
574 #define DBGDATA(info, buf, size, label)
575 #endif
576 
577 #ifdef DBGTBUF
578 static void dump_tbufs(struct slgt_info *info)
579 {
580 	int i;
581 	printk("tbuf_current=%d\n", info->tbuf_current);
582 	for (i=0 ; i < info->tbuf_count ; i++) {
583 		printk("%d: count=%04X status=%04X\n",
584 			i, le16_to_cpu(info->tbufs[i].count), le16_to_cpu(info->tbufs[i].status));
585 	}
586 }
587 #else
588 #define DBGTBUF(info)
589 #endif
590 
591 #ifdef DBGRBUF
592 static void dump_rbufs(struct slgt_info *info)
593 {
594 	int i;
595 	printk("rbuf_current=%d\n", info->rbuf_current);
596 	for (i=0 ; i < info->rbuf_count ; i++) {
597 		printk("%d: count=%04X status=%04X\n",
598 			i, le16_to_cpu(info->rbufs[i].count), le16_to_cpu(info->rbufs[i].status));
599 	}
600 }
601 #else
602 #define DBGRBUF(info)
603 #endif
604 
605 static inline int sanity_check(struct slgt_info *info, char *devname, const char *name)
606 {
607 #ifdef SANITY_CHECK
608 	if (!info) {
609 		printk("null struct slgt_info for (%s) in %s\n", devname, name);
610 		return 1;
611 	}
612 	if (info->magic != MGSL_MAGIC) {
613 		printk("bad magic number struct slgt_info (%s) in %s\n", devname, name);
614 		return 1;
615 	}
616 #else
617 	if (!info)
618 		return 1;
619 #endif
620 	return 0;
621 }
622 
623 /**
624  * line discipline callback wrappers
625  *
626  * The wrappers maintain line discipline references
627  * while calling into the line discipline.
628  *
629  * ldisc_receive_buf  - pass receive data to line discipline
630  */
631 static void ldisc_receive_buf(struct tty_struct *tty,
632 			      const __u8 *data, char *flags, int count)
633 {
634 	struct tty_ldisc *ld;
635 	if (!tty)
636 		return;
637 	ld = tty_ldisc_ref(tty);
638 	if (ld) {
639 		if (ld->ops->receive_buf)
640 			ld->ops->receive_buf(tty, data, flags, count);
641 		tty_ldisc_deref(ld);
642 	}
643 }
644 
645 /* tty callbacks */
646 
647 static int open(struct tty_struct *tty, struct file *filp)
648 {
649 	struct slgt_info *info;
650 	int retval, line;
651 	unsigned long flags;
652 
653 	line = tty->index;
654 	if (line >= slgt_device_count) {
655 		DBGERR(("%s: open with invalid line #%d.\n", driver_name, line));
656 		return -ENODEV;
657 	}
658 
659 	info = slgt_device_list;
660 	while(info && info->line != line)
661 		info = info->next_device;
662 	if (sanity_check(info, tty->name, "open"))
663 		return -ENODEV;
664 	if (info->init_error) {
665 		DBGERR(("%s init error=%d\n", info->device_name, info->init_error));
666 		return -ENODEV;
667 	}
668 
669 	tty->driver_data = info;
670 	info->port.tty = tty;
671 
672 	DBGINFO(("%s open, old ref count = %d\n", info->device_name, info->port.count));
673 
674 	mutex_lock(&info->port.mutex);
675 	info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
676 
677 	spin_lock_irqsave(&info->netlock, flags);
678 	if (info->netcount) {
679 		retval = -EBUSY;
680 		spin_unlock_irqrestore(&info->netlock, flags);
681 		mutex_unlock(&info->port.mutex);
682 		goto cleanup;
683 	}
684 	info->port.count++;
685 	spin_unlock_irqrestore(&info->netlock, flags);
686 
687 	if (info->port.count == 1) {
688 		/* 1st open on this device, init hardware */
689 		retval = startup(info);
690 		if (retval < 0) {
691 			mutex_unlock(&info->port.mutex);
692 			goto cleanup;
693 		}
694 	}
695 	mutex_unlock(&info->port.mutex);
696 	retval = block_til_ready(tty, filp, info);
697 	if (retval) {
698 		DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval));
699 		goto cleanup;
700 	}
701 
702 	retval = 0;
703 
704 cleanup:
705 	if (retval) {
706 		if (tty->count == 1)
707 			info->port.tty = NULL; /* tty layer will release tty struct */
708 		if(info->port.count)
709 			info->port.count--;
710 	}
711 
712 	DBGINFO(("%s open rc=%d\n", info->device_name, retval));
713 	return retval;
714 }
715 
716 static void close(struct tty_struct *tty, struct file *filp)
717 {
718 	struct slgt_info *info = tty->driver_data;
719 
720 	if (sanity_check(info, tty->name, "close"))
721 		return;
722 	DBGINFO(("%s close entry, count=%d\n", info->device_name, info->port.count));
723 
724 	if (tty_port_close_start(&info->port, tty, filp) == 0)
725 		goto cleanup;
726 
727 	mutex_lock(&info->port.mutex);
728 	if (tty_port_initialized(&info->port))
729  		wait_until_sent(tty, info->timeout);
730 	flush_buffer(tty);
731 	tty_ldisc_flush(tty);
732 
733 	shutdown(info);
734 	mutex_unlock(&info->port.mutex);
735 
736 	tty_port_close_end(&info->port, tty);
737 	info->port.tty = NULL;
738 cleanup:
739 	DBGINFO(("%s close exit, count=%d\n", tty->driver->name, info->port.count));
740 }
741 
742 static void hangup(struct tty_struct *tty)
743 {
744 	struct slgt_info *info = tty->driver_data;
745 	unsigned long flags;
746 
747 	if (sanity_check(info, tty->name, "hangup"))
748 		return;
749 	DBGINFO(("%s hangup\n", info->device_name));
750 
751 	flush_buffer(tty);
752 
753 	mutex_lock(&info->port.mutex);
754 	shutdown(info);
755 
756 	spin_lock_irqsave(&info->port.lock, flags);
757 	info->port.count = 0;
758 	info->port.tty = NULL;
759 	spin_unlock_irqrestore(&info->port.lock, flags);
760 	tty_port_set_active(&info->port, 0);
761 	mutex_unlock(&info->port.mutex);
762 
763 	wake_up_interruptible(&info->port.open_wait);
764 }
765 
766 static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
767 {
768 	struct slgt_info *info = tty->driver_data;
769 	unsigned long flags;
770 
771 	DBGINFO(("%s set_termios\n", tty->driver->name));
772 
773 	change_params(info);
774 
775 	/* Handle transition to B0 status */
776 	if ((old_termios->c_cflag & CBAUD) && !C_BAUD(tty)) {
777 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
778 		spin_lock_irqsave(&info->lock,flags);
779 		set_signals(info);
780 		spin_unlock_irqrestore(&info->lock,flags);
781 	}
782 
783 	/* Handle transition away from B0 status */
784 	if (!(old_termios->c_cflag & CBAUD) && C_BAUD(tty)) {
785 		info->signals |= SerialSignal_DTR;
786 		if (!C_CRTSCTS(tty) || !tty_throttled(tty))
787 			info->signals |= SerialSignal_RTS;
788 		spin_lock_irqsave(&info->lock,flags);
789 	 	set_signals(info);
790 		spin_unlock_irqrestore(&info->lock,flags);
791 	}
792 
793 	/* Handle turning off CRTSCTS */
794 	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
795 		tty->hw_stopped = 0;
796 		tx_release(tty);
797 	}
798 }
799 
800 static void update_tx_timer(struct slgt_info *info)
801 {
802 	/*
803 	 * use worst case speed of 1200bps to calculate transmit timeout
804 	 * based on data in buffers (tbuf_bytes) and FIFO (128 bytes)
805 	 */
806 	if (info->params.mode == MGSL_MODE_HDLC) {
807 		int timeout  = (tbuf_bytes(info) * 7) + 1000;
808 		mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(timeout));
809 	}
810 }
811 
812 static int write(struct tty_struct *tty,
813 		 const unsigned char *buf, int count)
814 {
815 	int ret = 0;
816 	struct slgt_info *info = tty->driver_data;
817 	unsigned long flags;
818 
819 	if (sanity_check(info, tty->name, "write"))
820 		return -EIO;
821 
822 	DBGINFO(("%s write count=%d\n", info->device_name, count));
823 
824 	if (!info->tx_buf || (count > info->max_frame_size))
825 		return -EIO;
826 
827 	if (!count || tty->stopped || tty->hw_stopped)
828 		return 0;
829 
830 	spin_lock_irqsave(&info->lock, flags);
831 
832 	if (info->tx_count) {
833 		/* send accumulated data from send_char() */
834 		if (!tx_load(info, info->tx_buf, info->tx_count))
835 			goto cleanup;
836 		info->tx_count = 0;
837 	}
838 
839 	if (tx_load(info, buf, count))
840 		ret = count;
841 
842 cleanup:
843 	spin_unlock_irqrestore(&info->lock, flags);
844 	DBGINFO(("%s write rc=%d\n", info->device_name, ret));
845 	return ret;
846 }
847 
848 static int put_char(struct tty_struct *tty, unsigned char ch)
849 {
850 	struct slgt_info *info = tty->driver_data;
851 	unsigned long flags;
852 	int ret = 0;
853 
854 	if (sanity_check(info, tty->name, "put_char"))
855 		return 0;
856 	DBGINFO(("%s put_char(%d)\n", info->device_name, ch));
857 	if (!info->tx_buf)
858 		return 0;
859 	spin_lock_irqsave(&info->lock,flags);
860 	if (info->tx_count < info->max_frame_size) {
861 		info->tx_buf[info->tx_count++] = ch;
862 		ret = 1;
863 	}
864 	spin_unlock_irqrestore(&info->lock,flags);
865 	return ret;
866 }
867 
868 static void send_xchar(struct tty_struct *tty, char ch)
869 {
870 	struct slgt_info *info = tty->driver_data;
871 	unsigned long flags;
872 
873 	if (sanity_check(info, tty->name, "send_xchar"))
874 		return;
875 	DBGINFO(("%s send_xchar(%d)\n", info->device_name, ch));
876 	info->x_char = ch;
877 	if (ch) {
878 		spin_lock_irqsave(&info->lock,flags);
879 		if (!info->tx_enabled)
880 		 	tx_start(info);
881 		spin_unlock_irqrestore(&info->lock,flags);
882 	}
883 }
884 
885 static void wait_until_sent(struct tty_struct *tty, int timeout)
886 {
887 	struct slgt_info *info = tty->driver_data;
888 	unsigned long orig_jiffies, char_time;
889 
890 	if (!info )
891 		return;
892 	if (sanity_check(info, tty->name, "wait_until_sent"))
893 		return;
894 	DBGINFO(("%s wait_until_sent entry\n", info->device_name));
895 	if (!tty_port_initialized(&info->port))
896 		goto exit;
897 
898 	orig_jiffies = jiffies;
899 
900 	/* Set check interval to 1/5 of estimated time to
901 	 * send a character, and make it at least 1. The check
902 	 * interval should also be less than the timeout.
903 	 * Note: use tight timings here to satisfy the NIST-PCTS.
904 	 */
905 
906 	if (info->params.data_rate) {
907 	       	char_time = info->timeout/(32 * 5);
908 		if (!char_time)
909 			char_time++;
910 	} else
911 		char_time = 1;
912 
913 	if (timeout)
914 		char_time = min_t(unsigned long, char_time, timeout);
915 
916 	while (info->tx_active) {
917 		msleep_interruptible(jiffies_to_msecs(char_time));
918 		if (signal_pending(current))
919 			break;
920 		if (timeout && time_after(jiffies, orig_jiffies + timeout))
921 			break;
922 	}
923 exit:
924 	DBGINFO(("%s wait_until_sent exit\n", info->device_name));
925 }
926 
927 static int write_room(struct tty_struct *tty)
928 {
929 	struct slgt_info *info = tty->driver_data;
930 	int ret;
931 
932 	if (sanity_check(info, tty->name, "write_room"))
933 		return 0;
934 	ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
935 	DBGINFO(("%s write_room=%d\n", info->device_name, ret));
936 	return ret;
937 }
938 
939 static void flush_chars(struct tty_struct *tty)
940 {
941 	struct slgt_info *info = tty->driver_data;
942 	unsigned long flags;
943 
944 	if (sanity_check(info, tty->name, "flush_chars"))
945 		return;
946 	DBGINFO(("%s flush_chars entry tx_count=%d\n", info->device_name, info->tx_count));
947 
948 	if (info->tx_count <= 0 || tty->stopped ||
949 	    tty->hw_stopped || !info->tx_buf)
950 		return;
951 
952 	DBGINFO(("%s flush_chars start transmit\n", info->device_name));
953 
954 	spin_lock_irqsave(&info->lock,flags);
955 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
956 		info->tx_count = 0;
957 	spin_unlock_irqrestore(&info->lock,flags);
958 }
959 
960 static void flush_buffer(struct tty_struct *tty)
961 {
962 	struct slgt_info *info = tty->driver_data;
963 	unsigned long flags;
964 
965 	if (sanity_check(info, tty->name, "flush_buffer"))
966 		return;
967 	DBGINFO(("%s flush_buffer\n", info->device_name));
968 
969 	spin_lock_irqsave(&info->lock, flags);
970 	info->tx_count = 0;
971 	spin_unlock_irqrestore(&info->lock, flags);
972 
973 	tty_wakeup(tty);
974 }
975 
976 /*
977  * throttle (stop) transmitter
978  */
979 static void tx_hold(struct tty_struct *tty)
980 {
981 	struct slgt_info *info = tty->driver_data;
982 	unsigned long flags;
983 
984 	if (sanity_check(info, tty->name, "tx_hold"))
985 		return;
986 	DBGINFO(("%s tx_hold\n", info->device_name));
987 	spin_lock_irqsave(&info->lock,flags);
988 	if (info->tx_enabled && info->params.mode == MGSL_MODE_ASYNC)
989 	 	tx_stop(info);
990 	spin_unlock_irqrestore(&info->lock,flags);
991 }
992 
993 /*
994  * release (start) transmitter
995  */
996 static void tx_release(struct tty_struct *tty)
997 {
998 	struct slgt_info *info = tty->driver_data;
999 	unsigned long flags;
1000 
1001 	if (sanity_check(info, tty->name, "tx_release"))
1002 		return;
1003 	DBGINFO(("%s tx_release\n", info->device_name));
1004 	spin_lock_irqsave(&info->lock, flags);
1005 	if (info->tx_count && tx_load(info, info->tx_buf, info->tx_count))
1006 		info->tx_count = 0;
1007 	spin_unlock_irqrestore(&info->lock, flags);
1008 }
1009 
1010 /*
1011  * Service an IOCTL request
1012  *
1013  * Arguments
1014  *
1015  * 	tty	pointer to tty instance data
1016  * 	cmd	IOCTL command code
1017  * 	arg	command argument/context
1018  *
1019  * Return 0 if success, otherwise error code
1020  */
1021 static int ioctl(struct tty_struct *tty,
1022 		 unsigned int cmd, unsigned long arg)
1023 {
1024 	struct slgt_info *info = tty->driver_data;
1025 	void __user *argp = (void __user *)arg;
1026 	int ret;
1027 
1028 	if (sanity_check(info, tty->name, "ioctl"))
1029 		return -ENODEV;
1030 	DBGINFO(("%s ioctl() cmd=%08X\n", info->device_name, cmd));
1031 
1032 	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
1033 	    (cmd != TIOCMIWAIT)) {
1034 		if (tty_io_error(tty))
1035 		    return -EIO;
1036 	}
1037 
1038 	switch (cmd) {
1039 	case MGSL_IOCWAITEVENT:
1040 		return wait_mgsl_event(info, argp);
1041 	case TIOCMIWAIT:
1042 		return modem_input_wait(info,(int)arg);
1043 	case MGSL_IOCSGPIO:
1044 		return set_gpio(info, argp);
1045 	case MGSL_IOCGGPIO:
1046 		return get_gpio(info, argp);
1047 	case MGSL_IOCWAITGPIO:
1048 		return wait_gpio(info, argp);
1049 	case MGSL_IOCGXSYNC:
1050 		return get_xsync(info, argp);
1051 	case MGSL_IOCSXSYNC:
1052 		return set_xsync(info, (int)arg);
1053 	case MGSL_IOCGXCTRL:
1054 		return get_xctrl(info, argp);
1055 	case MGSL_IOCSXCTRL:
1056 		return set_xctrl(info, (int)arg);
1057 	}
1058 	mutex_lock(&info->port.mutex);
1059 	switch (cmd) {
1060 	case MGSL_IOCGPARAMS:
1061 		ret = get_params(info, argp);
1062 		break;
1063 	case MGSL_IOCSPARAMS:
1064 		ret = set_params(info, argp);
1065 		break;
1066 	case MGSL_IOCGTXIDLE:
1067 		ret = get_txidle(info, argp);
1068 		break;
1069 	case MGSL_IOCSTXIDLE:
1070 		ret = set_txidle(info, (int)arg);
1071 		break;
1072 	case MGSL_IOCTXENABLE:
1073 		ret = tx_enable(info, (int)arg);
1074 		break;
1075 	case MGSL_IOCRXENABLE:
1076 		ret = rx_enable(info, (int)arg);
1077 		break;
1078 	case MGSL_IOCTXABORT:
1079 		ret = tx_abort(info);
1080 		break;
1081 	case MGSL_IOCGSTATS:
1082 		ret = get_stats(info, argp);
1083 		break;
1084 	case MGSL_IOCGIF:
1085 		ret = get_interface(info, argp);
1086 		break;
1087 	case MGSL_IOCSIF:
1088 		ret = set_interface(info,(int)arg);
1089 		break;
1090 	default:
1091 		ret = -ENOIOCTLCMD;
1092 	}
1093 	mutex_unlock(&info->port.mutex);
1094 	return ret;
1095 }
1096 
1097 static int get_icount(struct tty_struct *tty,
1098 				struct serial_icounter_struct *icount)
1099 
1100 {
1101 	struct slgt_info *info = tty->driver_data;
1102 	struct mgsl_icount cnow;	/* kernel counter temps */
1103 	unsigned long flags;
1104 
1105 	spin_lock_irqsave(&info->lock,flags);
1106 	cnow = info->icount;
1107 	spin_unlock_irqrestore(&info->lock,flags);
1108 
1109 	icount->cts = cnow.cts;
1110 	icount->dsr = cnow.dsr;
1111 	icount->rng = cnow.rng;
1112 	icount->dcd = cnow.dcd;
1113 	icount->rx = cnow.rx;
1114 	icount->tx = cnow.tx;
1115 	icount->frame = cnow.frame;
1116 	icount->overrun = cnow.overrun;
1117 	icount->parity = cnow.parity;
1118 	icount->brk = cnow.brk;
1119 	icount->buf_overrun = cnow.buf_overrun;
1120 
1121 	return 0;
1122 }
1123 
1124 /*
1125  * support for 32 bit ioctl calls on 64 bit systems
1126  */
1127 #ifdef CONFIG_COMPAT
1128 static long get_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *user_params)
1129 {
1130 	struct MGSL_PARAMS32 tmp_params;
1131 
1132 	DBGINFO(("%s get_params32\n", info->device_name));
1133 	memset(&tmp_params, 0, sizeof(tmp_params));
1134 	tmp_params.mode            = (compat_ulong_t)info->params.mode;
1135 	tmp_params.loopback        = info->params.loopback;
1136 	tmp_params.flags           = info->params.flags;
1137 	tmp_params.encoding        = info->params.encoding;
1138 	tmp_params.clock_speed     = (compat_ulong_t)info->params.clock_speed;
1139 	tmp_params.addr_filter     = info->params.addr_filter;
1140 	tmp_params.crc_type        = info->params.crc_type;
1141 	tmp_params.preamble_length = info->params.preamble_length;
1142 	tmp_params.preamble        = info->params.preamble;
1143 	tmp_params.data_rate       = (compat_ulong_t)info->params.data_rate;
1144 	tmp_params.data_bits       = info->params.data_bits;
1145 	tmp_params.stop_bits       = info->params.stop_bits;
1146 	tmp_params.parity          = info->params.parity;
1147 	if (copy_to_user(user_params, &tmp_params, sizeof(struct MGSL_PARAMS32)))
1148 		return -EFAULT;
1149 	return 0;
1150 }
1151 
1152 static long set_params32(struct slgt_info *info, struct MGSL_PARAMS32 __user *new_params)
1153 {
1154 	struct MGSL_PARAMS32 tmp_params;
1155 
1156 	DBGINFO(("%s set_params32\n", info->device_name));
1157 	if (copy_from_user(&tmp_params, new_params, sizeof(struct MGSL_PARAMS32)))
1158 		return -EFAULT;
1159 
1160 	spin_lock(&info->lock);
1161 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK) {
1162 		info->base_clock = tmp_params.clock_speed;
1163 	} else {
1164 		info->params.mode            = tmp_params.mode;
1165 		info->params.loopback        = tmp_params.loopback;
1166 		info->params.flags           = tmp_params.flags;
1167 		info->params.encoding        = tmp_params.encoding;
1168 		info->params.clock_speed     = tmp_params.clock_speed;
1169 		info->params.addr_filter     = tmp_params.addr_filter;
1170 		info->params.crc_type        = tmp_params.crc_type;
1171 		info->params.preamble_length = tmp_params.preamble_length;
1172 		info->params.preamble        = tmp_params.preamble;
1173 		info->params.data_rate       = tmp_params.data_rate;
1174 		info->params.data_bits       = tmp_params.data_bits;
1175 		info->params.stop_bits       = tmp_params.stop_bits;
1176 		info->params.parity          = tmp_params.parity;
1177 	}
1178 	spin_unlock(&info->lock);
1179 
1180 	program_hw(info);
1181 
1182 	return 0;
1183 }
1184 
1185 static long slgt_compat_ioctl(struct tty_struct *tty,
1186 			 unsigned int cmd, unsigned long arg)
1187 {
1188 	struct slgt_info *info = tty->driver_data;
1189 	int rc = -ENOIOCTLCMD;
1190 
1191 	if (sanity_check(info, tty->name, "compat_ioctl"))
1192 		return -ENODEV;
1193 	DBGINFO(("%s compat_ioctl() cmd=%08X\n", info->device_name, cmd));
1194 
1195 	switch (cmd) {
1196 
1197 	case MGSL_IOCSPARAMS32:
1198 		rc = set_params32(info, compat_ptr(arg));
1199 		break;
1200 
1201 	case MGSL_IOCGPARAMS32:
1202 		rc = get_params32(info, compat_ptr(arg));
1203 		break;
1204 
1205 	case MGSL_IOCGPARAMS:
1206 	case MGSL_IOCSPARAMS:
1207 	case MGSL_IOCGTXIDLE:
1208 	case MGSL_IOCGSTATS:
1209 	case MGSL_IOCWAITEVENT:
1210 	case MGSL_IOCGIF:
1211 	case MGSL_IOCSGPIO:
1212 	case MGSL_IOCGGPIO:
1213 	case MGSL_IOCWAITGPIO:
1214 	case MGSL_IOCGXSYNC:
1215 	case MGSL_IOCGXCTRL:
1216 	case MGSL_IOCSTXIDLE:
1217 	case MGSL_IOCTXENABLE:
1218 	case MGSL_IOCRXENABLE:
1219 	case MGSL_IOCTXABORT:
1220 	case TIOCMIWAIT:
1221 	case MGSL_IOCSIF:
1222 	case MGSL_IOCSXSYNC:
1223 	case MGSL_IOCSXCTRL:
1224 		rc = ioctl(tty, cmd, arg);
1225 		break;
1226 	}
1227 
1228 	DBGINFO(("%s compat_ioctl() cmd=%08X rc=%d\n", info->device_name, cmd, rc));
1229 	return rc;
1230 }
1231 #else
1232 #define slgt_compat_ioctl NULL
1233 #endif /* ifdef CONFIG_COMPAT */
1234 
1235 /*
1236  * proc fs support
1237  */
1238 static inline void line_info(struct seq_file *m, struct slgt_info *info)
1239 {
1240 	char stat_buf[30];
1241 	unsigned long flags;
1242 
1243 	seq_printf(m, "%s: IO=%08X IRQ=%d MaxFrameSize=%u\n",
1244 		      info->device_name, info->phys_reg_addr,
1245 		      info->irq_level, info->max_frame_size);
1246 
1247 	/* output current serial signal states */
1248 	spin_lock_irqsave(&info->lock,flags);
1249 	get_signals(info);
1250 	spin_unlock_irqrestore(&info->lock,flags);
1251 
1252 	stat_buf[0] = 0;
1253 	stat_buf[1] = 0;
1254 	if (info->signals & SerialSignal_RTS)
1255 		strcat(stat_buf, "|RTS");
1256 	if (info->signals & SerialSignal_CTS)
1257 		strcat(stat_buf, "|CTS");
1258 	if (info->signals & SerialSignal_DTR)
1259 		strcat(stat_buf, "|DTR");
1260 	if (info->signals & SerialSignal_DSR)
1261 		strcat(stat_buf, "|DSR");
1262 	if (info->signals & SerialSignal_DCD)
1263 		strcat(stat_buf, "|CD");
1264 	if (info->signals & SerialSignal_RI)
1265 		strcat(stat_buf, "|RI");
1266 
1267 	if (info->params.mode != MGSL_MODE_ASYNC) {
1268 		seq_printf(m, "\tHDLC txok:%d rxok:%d",
1269 			       info->icount.txok, info->icount.rxok);
1270 		if (info->icount.txunder)
1271 			seq_printf(m, " txunder:%d", info->icount.txunder);
1272 		if (info->icount.txabort)
1273 			seq_printf(m, " txabort:%d", info->icount.txabort);
1274 		if (info->icount.rxshort)
1275 			seq_printf(m, " rxshort:%d", info->icount.rxshort);
1276 		if (info->icount.rxlong)
1277 			seq_printf(m, " rxlong:%d", info->icount.rxlong);
1278 		if (info->icount.rxover)
1279 			seq_printf(m, " rxover:%d", info->icount.rxover);
1280 		if (info->icount.rxcrc)
1281 			seq_printf(m, " rxcrc:%d", info->icount.rxcrc);
1282 	} else {
1283 		seq_printf(m, "\tASYNC tx:%d rx:%d",
1284 			       info->icount.tx, info->icount.rx);
1285 		if (info->icount.frame)
1286 			seq_printf(m, " fe:%d", info->icount.frame);
1287 		if (info->icount.parity)
1288 			seq_printf(m, " pe:%d", info->icount.parity);
1289 		if (info->icount.brk)
1290 			seq_printf(m, " brk:%d", info->icount.brk);
1291 		if (info->icount.overrun)
1292 			seq_printf(m, " oe:%d", info->icount.overrun);
1293 	}
1294 
1295 	/* Append serial signal status to end */
1296 	seq_printf(m, " %s\n", stat_buf+1);
1297 
1298 	seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
1299 		       info->tx_active,info->bh_requested,info->bh_running,
1300 		       info->pending_bh);
1301 }
1302 
1303 /* Called to print information about devices
1304  */
1305 static int synclink_gt_proc_show(struct seq_file *m, void *v)
1306 {
1307 	struct slgt_info *info;
1308 
1309 	seq_puts(m, "synclink_gt driver\n");
1310 
1311 	info = slgt_device_list;
1312 	while( info ) {
1313 		line_info(m, info);
1314 		info = info->next_device;
1315 	}
1316 	return 0;
1317 }
1318 
1319 /*
1320  * return count of bytes in transmit buffer
1321  */
1322 static int chars_in_buffer(struct tty_struct *tty)
1323 {
1324 	struct slgt_info *info = tty->driver_data;
1325 	int count;
1326 	if (sanity_check(info, tty->name, "chars_in_buffer"))
1327 		return 0;
1328 	count = tbuf_bytes(info);
1329 	DBGINFO(("%s chars_in_buffer()=%d\n", info->device_name, count));
1330 	return count;
1331 }
1332 
1333 /*
1334  * signal remote device to throttle send data (our receive data)
1335  */
1336 static void throttle(struct tty_struct * tty)
1337 {
1338 	struct slgt_info *info = tty->driver_data;
1339 	unsigned long flags;
1340 
1341 	if (sanity_check(info, tty->name, "throttle"))
1342 		return;
1343 	DBGINFO(("%s throttle\n", info->device_name));
1344 	if (I_IXOFF(tty))
1345 		send_xchar(tty, STOP_CHAR(tty));
1346  	if (C_CRTSCTS(tty)) {
1347 		spin_lock_irqsave(&info->lock,flags);
1348 		info->signals &= ~SerialSignal_RTS;
1349 	 	set_signals(info);
1350 		spin_unlock_irqrestore(&info->lock,flags);
1351 	}
1352 }
1353 
1354 /*
1355  * signal remote device to stop throttling send data (our receive data)
1356  */
1357 static void unthrottle(struct tty_struct * tty)
1358 {
1359 	struct slgt_info *info = tty->driver_data;
1360 	unsigned long flags;
1361 
1362 	if (sanity_check(info, tty->name, "unthrottle"))
1363 		return;
1364 	DBGINFO(("%s unthrottle\n", info->device_name));
1365 	if (I_IXOFF(tty)) {
1366 		if (info->x_char)
1367 			info->x_char = 0;
1368 		else
1369 			send_xchar(tty, START_CHAR(tty));
1370 	}
1371  	if (C_CRTSCTS(tty)) {
1372 		spin_lock_irqsave(&info->lock,flags);
1373 		info->signals |= SerialSignal_RTS;
1374 	 	set_signals(info);
1375 		spin_unlock_irqrestore(&info->lock,flags);
1376 	}
1377 }
1378 
1379 /*
1380  * set or clear transmit break condition
1381  * break_state	-1=set break condition, 0=clear
1382  */
1383 static int set_break(struct tty_struct *tty, int break_state)
1384 {
1385 	struct slgt_info *info = tty->driver_data;
1386 	unsigned short value;
1387 	unsigned long flags;
1388 
1389 	if (sanity_check(info, tty->name, "set_break"))
1390 		return -EINVAL;
1391 	DBGINFO(("%s set_break(%d)\n", info->device_name, break_state));
1392 
1393 	spin_lock_irqsave(&info->lock,flags);
1394 	value = rd_reg16(info, TCR);
1395  	if (break_state == -1)
1396 		value |= BIT6;
1397 	else
1398 		value &= ~BIT6;
1399 	wr_reg16(info, TCR, value);
1400 	spin_unlock_irqrestore(&info->lock,flags);
1401 	return 0;
1402 }
1403 
1404 #if SYNCLINK_GENERIC_HDLC
1405 
1406 /**
1407  * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
1408  * set encoding and frame check sequence (FCS) options
1409  *
1410  * dev       pointer to network device structure
1411  * encoding  serial encoding setting
1412  * parity    FCS setting
1413  *
1414  * returns 0 if success, otherwise error code
1415  */
1416 static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
1417 			  unsigned short parity)
1418 {
1419 	struct slgt_info *info = dev_to_port(dev);
1420 	unsigned char  new_encoding;
1421 	unsigned short new_crctype;
1422 
1423 	/* return error if TTY interface open */
1424 	if (info->port.count)
1425 		return -EBUSY;
1426 
1427 	DBGINFO(("%s hdlcdev_attach\n", info->device_name));
1428 
1429 	switch (encoding)
1430 	{
1431 	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
1432 	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
1433 	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
1434 	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
1435 	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
1436 	default: return -EINVAL;
1437 	}
1438 
1439 	switch (parity)
1440 	{
1441 	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
1442 	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
1443 	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
1444 	default: return -EINVAL;
1445 	}
1446 
1447 	info->params.encoding = new_encoding;
1448 	info->params.crc_type = new_crctype;
1449 
1450 	/* if network interface up, reprogram hardware */
1451 	if (info->netcount)
1452 		program_hw(info);
1453 
1454 	return 0;
1455 }
1456 
1457 /**
1458  * called by generic HDLC layer to send frame
1459  *
1460  * skb  socket buffer containing HDLC frame
1461  * dev  pointer to network device structure
1462  */
1463 static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
1464 				      struct net_device *dev)
1465 {
1466 	struct slgt_info *info = dev_to_port(dev);
1467 	unsigned long flags;
1468 
1469 	DBGINFO(("%s hdlc_xmit\n", dev->name));
1470 
1471 	if (!skb->len)
1472 		return NETDEV_TX_OK;
1473 
1474 	/* stop sending until this frame completes */
1475 	netif_stop_queue(dev);
1476 
1477 	/* update network statistics */
1478 	dev->stats.tx_packets++;
1479 	dev->stats.tx_bytes += skb->len;
1480 
1481 	/* save start time for transmit timeout detection */
1482 	netif_trans_update(dev);
1483 
1484 	spin_lock_irqsave(&info->lock, flags);
1485 	tx_load(info, skb->data, skb->len);
1486 	spin_unlock_irqrestore(&info->lock, flags);
1487 
1488 	/* done with socket buffer, so free it */
1489 	dev_kfree_skb(skb);
1490 
1491 	return NETDEV_TX_OK;
1492 }
1493 
1494 /**
1495  * called by network layer when interface enabled
1496  * claim resources and initialize hardware
1497  *
1498  * dev  pointer to network device structure
1499  *
1500  * returns 0 if success, otherwise error code
1501  */
1502 static int hdlcdev_open(struct net_device *dev)
1503 {
1504 	struct slgt_info *info = dev_to_port(dev);
1505 	int rc;
1506 	unsigned long flags;
1507 
1508 	if (!try_module_get(THIS_MODULE))
1509 		return -EBUSY;
1510 
1511 	DBGINFO(("%s hdlcdev_open\n", dev->name));
1512 
1513 	/* generic HDLC layer open processing */
1514 	rc = hdlc_open(dev);
1515 	if (rc)
1516 		return rc;
1517 
1518 	/* arbitrate between network and tty opens */
1519 	spin_lock_irqsave(&info->netlock, flags);
1520 	if (info->port.count != 0 || info->netcount != 0) {
1521 		DBGINFO(("%s hdlc_open busy\n", dev->name));
1522 		spin_unlock_irqrestore(&info->netlock, flags);
1523 		return -EBUSY;
1524 	}
1525 	info->netcount=1;
1526 	spin_unlock_irqrestore(&info->netlock, flags);
1527 
1528 	/* claim resources and init adapter */
1529 	if ((rc = startup(info)) != 0) {
1530 		spin_lock_irqsave(&info->netlock, flags);
1531 		info->netcount=0;
1532 		spin_unlock_irqrestore(&info->netlock, flags);
1533 		return rc;
1534 	}
1535 
1536 	/* assert RTS and DTR, apply hardware settings */
1537 	info->signals |= SerialSignal_RTS | SerialSignal_DTR;
1538 	program_hw(info);
1539 
1540 	/* enable network layer transmit */
1541 	netif_trans_update(dev);
1542 	netif_start_queue(dev);
1543 
1544 	/* inform generic HDLC layer of current DCD status */
1545 	spin_lock_irqsave(&info->lock, flags);
1546 	get_signals(info);
1547 	spin_unlock_irqrestore(&info->lock, flags);
1548 	if (info->signals & SerialSignal_DCD)
1549 		netif_carrier_on(dev);
1550 	else
1551 		netif_carrier_off(dev);
1552 	return 0;
1553 }
1554 
1555 /**
1556  * called by network layer when interface is disabled
1557  * shutdown hardware and release resources
1558  *
1559  * dev  pointer to network device structure
1560  *
1561  * returns 0 if success, otherwise error code
1562  */
1563 static int hdlcdev_close(struct net_device *dev)
1564 {
1565 	struct slgt_info *info = dev_to_port(dev);
1566 	unsigned long flags;
1567 
1568 	DBGINFO(("%s hdlcdev_close\n", dev->name));
1569 
1570 	netif_stop_queue(dev);
1571 
1572 	/* shutdown adapter and release resources */
1573 	shutdown(info);
1574 
1575 	hdlc_close(dev);
1576 
1577 	spin_lock_irqsave(&info->netlock, flags);
1578 	info->netcount=0;
1579 	spin_unlock_irqrestore(&info->netlock, flags);
1580 
1581 	module_put(THIS_MODULE);
1582 	return 0;
1583 }
1584 
1585 /**
1586  * called by network layer to process IOCTL call to network device
1587  *
1588  * dev  pointer to network device structure
1589  * ifr  pointer to network interface request structure
1590  * cmd  IOCTL command code
1591  *
1592  * returns 0 if success, otherwise error code
1593  */
1594 static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1595 {
1596 	const size_t size = sizeof(sync_serial_settings);
1597 	sync_serial_settings new_line;
1598 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1599 	struct slgt_info *info = dev_to_port(dev);
1600 	unsigned int flags;
1601 
1602 	DBGINFO(("%s hdlcdev_ioctl\n", dev->name));
1603 
1604 	/* return error if TTY interface open */
1605 	if (info->port.count)
1606 		return -EBUSY;
1607 
1608 	if (cmd != SIOCWANDEV)
1609 		return hdlc_ioctl(dev, ifr, cmd);
1610 
1611 	memset(&new_line, 0, sizeof(new_line));
1612 
1613 	switch(ifr->ifr_settings.type) {
1614 	case IF_GET_IFACE: /* return current sync_serial_settings */
1615 
1616 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
1617 		if (ifr->ifr_settings.size < size) {
1618 			ifr->ifr_settings.size = size; /* data size wanted */
1619 			return -ENOBUFS;
1620 		}
1621 
1622 		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1623 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1624 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1625 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1626 
1627 		switch (flags){
1628 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
1629 		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
1630 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
1631 		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
1632 		default: new_line.clock_type = CLOCK_DEFAULT;
1633 		}
1634 
1635 		new_line.clock_rate = info->params.clock_speed;
1636 		new_line.loopback   = info->params.loopback ? 1:0;
1637 
1638 		if (copy_to_user(line, &new_line, size))
1639 			return -EFAULT;
1640 		return 0;
1641 
1642 	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
1643 
1644 		if(!capable(CAP_NET_ADMIN))
1645 			return -EPERM;
1646 		if (copy_from_user(&new_line, line, size))
1647 			return -EFAULT;
1648 
1649 		switch (new_line.clock_type)
1650 		{
1651 		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
1652 		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
1653 		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
1654 		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
1655 		case CLOCK_DEFAULT:  flags = info->params.flags &
1656 					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1657 					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1658 					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1659 					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
1660 		default: return -EINVAL;
1661 		}
1662 
1663 		if (new_line.loopback != 0 && new_line.loopback != 1)
1664 			return -EINVAL;
1665 
1666 		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
1667 					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
1668 					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
1669 					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
1670 		info->params.flags |= flags;
1671 
1672 		info->params.loopback = new_line.loopback;
1673 
1674 		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
1675 			info->params.clock_speed = new_line.clock_rate;
1676 		else
1677 			info->params.clock_speed = 0;
1678 
1679 		/* if network interface up, reprogram hardware */
1680 		if (info->netcount)
1681 			program_hw(info);
1682 		return 0;
1683 
1684 	default:
1685 		return hdlc_ioctl(dev, ifr, cmd);
1686 	}
1687 }
1688 
1689 /**
1690  * called by network layer when transmit timeout is detected
1691  *
1692  * dev  pointer to network device structure
1693  */
1694 static void hdlcdev_tx_timeout(struct net_device *dev)
1695 {
1696 	struct slgt_info *info = dev_to_port(dev);
1697 	unsigned long flags;
1698 
1699 	DBGINFO(("%s hdlcdev_tx_timeout\n", dev->name));
1700 
1701 	dev->stats.tx_errors++;
1702 	dev->stats.tx_aborted_errors++;
1703 
1704 	spin_lock_irqsave(&info->lock,flags);
1705 	tx_stop(info);
1706 	spin_unlock_irqrestore(&info->lock,flags);
1707 
1708 	netif_wake_queue(dev);
1709 }
1710 
1711 /**
1712  * called by device driver when transmit completes
1713  * reenable network layer transmit if stopped
1714  *
1715  * info  pointer to device instance information
1716  */
1717 static void hdlcdev_tx_done(struct slgt_info *info)
1718 {
1719 	if (netif_queue_stopped(info->netdev))
1720 		netif_wake_queue(info->netdev);
1721 }
1722 
1723 /**
1724  * called by device driver when frame received
1725  * pass frame to network layer
1726  *
1727  * info  pointer to device instance information
1728  * buf   pointer to buffer contianing frame data
1729  * size  count of data bytes in buf
1730  */
1731 static void hdlcdev_rx(struct slgt_info *info, char *buf, int size)
1732 {
1733 	struct sk_buff *skb = dev_alloc_skb(size);
1734 	struct net_device *dev = info->netdev;
1735 
1736 	DBGINFO(("%s hdlcdev_rx\n", dev->name));
1737 
1738 	if (skb == NULL) {
1739 		DBGERR(("%s: can't alloc skb, drop packet\n", dev->name));
1740 		dev->stats.rx_dropped++;
1741 		return;
1742 	}
1743 
1744 	skb_put_data(skb, buf, size);
1745 
1746 	skb->protocol = hdlc_type_trans(skb, dev);
1747 
1748 	dev->stats.rx_packets++;
1749 	dev->stats.rx_bytes += size;
1750 
1751 	netif_rx(skb);
1752 }
1753 
1754 static const struct net_device_ops hdlcdev_ops = {
1755 	.ndo_open       = hdlcdev_open,
1756 	.ndo_stop       = hdlcdev_close,
1757 	.ndo_start_xmit = hdlc_start_xmit,
1758 	.ndo_do_ioctl   = hdlcdev_ioctl,
1759 	.ndo_tx_timeout = hdlcdev_tx_timeout,
1760 };
1761 
1762 /**
1763  * called by device driver when adding device instance
1764  * do generic HDLC initialization
1765  *
1766  * info  pointer to device instance information
1767  *
1768  * returns 0 if success, otherwise error code
1769  */
1770 static int hdlcdev_init(struct slgt_info *info)
1771 {
1772 	int rc;
1773 	struct net_device *dev;
1774 	hdlc_device *hdlc;
1775 
1776 	/* allocate and initialize network and HDLC layer objects */
1777 
1778 	dev = alloc_hdlcdev(info);
1779 	if (!dev) {
1780 		printk(KERN_ERR "%s hdlc device alloc failure\n", info->device_name);
1781 		return -ENOMEM;
1782 	}
1783 
1784 	/* for network layer reporting purposes only */
1785 	dev->mem_start = info->phys_reg_addr;
1786 	dev->mem_end   = info->phys_reg_addr + SLGT_REG_SIZE - 1;
1787 	dev->irq       = info->irq_level;
1788 
1789 	/* network layer callbacks and settings */
1790 	dev->netdev_ops	    = &hdlcdev_ops;
1791 	dev->watchdog_timeo = 10 * HZ;
1792 	dev->tx_queue_len   = 50;
1793 
1794 	/* generic HDLC layer callbacks and settings */
1795 	hdlc         = dev_to_hdlc(dev);
1796 	hdlc->attach = hdlcdev_attach;
1797 	hdlc->xmit   = hdlcdev_xmit;
1798 
1799 	/* register objects with HDLC layer */
1800 	rc = register_hdlc_device(dev);
1801 	if (rc) {
1802 		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
1803 		free_netdev(dev);
1804 		return rc;
1805 	}
1806 
1807 	info->netdev = dev;
1808 	return 0;
1809 }
1810 
1811 /**
1812  * called by device driver when removing device instance
1813  * do generic HDLC cleanup
1814  *
1815  * info  pointer to device instance information
1816  */
1817 static void hdlcdev_exit(struct slgt_info *info)
1818 {
1819 	unregister_hdlc_device(info->netdev);
1820 	free_netdev(info->netdev);
1821 	info->netdev = NULL;
1822 }
1823 
1824 #endif /* ifdef CONFIG_HDLC */
1825 
1826 /*
1827  * get async data from rx DMA buffers
1828  */
1829 static void rx_async(struct slgt_info *info)
1830 {
1831  	struct mgsl_icount *icount = &info->icount;
1832 	unsigned int start, end;
1833 	unsigned char *p;
1834 	unsigned char status;
1835 	struct slgt_desc *bufs = info->rbufs;
1836 	int i, count;
1837 	int chars = 0;
1838 	int stat;
1839 	unsigned char ch;
1840 
1841 	start = end = info->rbuf_current;
1842 
1843 	while(desc_complete(bufs[end])) {
1844 		count = desc_count(bufs[end]) - info->rbuf_index;
1845 		p     = bufs[end].buf + info->rbuf_index;
1846 
1847 		DBGISR(("%s rx_async count=%d\n", info->device_name, count));
1848 		DBGDATA(info, p, count, "rx");
1849 
1850 		for(i=0 ; i < count; i+=2, p+=2) {
1851 			ch = *p;
1852 			icount->rx++;
1853 
1854 			stat = 0;
1855 
1856 			status = *(p + 1) & (BIT1 + BIT0);
1857 			if (status) {
1858 				if (status & BIT1)
1859 					icount->parity++;
1860 				else if (status & BIT0)
1861 					icount->frame++;
1862 				/* discard char if tty control flags say so */
1863 				if (status & info->ignore_status_mask)
1864 					continue;
1865 				if (status & BIT1)
1866 					stat = TTY_PARITY;
1867 				else if (status & BIT0)
1868 					stat = TTY_FRAME;
1869 			}
1870 			tty_insert_flip_char(&info->port, ch, stat);
1871 			chars++;
1872 		}
1873 
1874 		if (i < count) {
1875 			/* receive buffer not completed */
1876 			info->rbuf_index += i;
1877 			mod_timer(&info->rx_timer, jiffies + 1);
1878 			break;
1879 		}
1880 
1881 		info->rbuf_index = 0;
1882 		free_rbufs(info, end, end);
1883 
1884 		if (++end == info->rbuf_count)
1885 			end = 0;
1886 
1887 		/* if entire list searched then no frame available */
1888 		if (end == start)
1889 			break;
1890 	}
1891 
1892 	if (chars)
1893 		tty_flip_buffer_push(&info->port);
1894 }
1895 
1896 /*
1897  * return next bottom half action to perform
1898  */
1899 static int bh_action(struct slgt_info *info)
1900 {
1901 	unsigned long flags;
1902 	int rc;
1903 
1904 	spin_lock_irqsave(&info->lock,flags);
1905 
1906 	if (info->pending_bh & BH_RECEIVE) {
1907 		info->pending_bh &= ~BH_RECEIVE;
1908 		rc = BH_RECEIVE;
1909 	} else if (info->pending_bh & BH_TRANSMIT) {
1910 		info->pending_bh &= ~BH_TRANSMIT;
1911 		rc = BH_TRANSMIT;
1912 	} else if (info->pending_bh & BH_STATUS) {
1913 		info->pending_bh &= ~BH_STATUS;
1914 		rc = BH_STATUS;
1915 	} else {
1916 		/* Mark BH routine as complete */
1917 		info->bh_running = false;
1918 		info->bh_requested = false;
1919 		rc = 0;
1920 	}
1921 
1922 	spin_unlock_irqrestore(&info->lock,flags);
1923 
1924 	return rc;
1925 }
1926 
1927 /*
1928  * perform bottom half processing
1929  */
1930 static void bh_handler(struct work_struct *work)
1931 {
1932 	struct slgt_info *info = container_of(work, struct slgt_info, task);
1933 	int action;
1934 
1935 	info->bh_running = true;
1936 
1937 	while((action = bh_action(info))) {
1938 		switch (action) {
1939 		case BH_RECEIVE:
1940 			DBGBH(("%s bh receive\n", info->device_name));
1941 			switch(info->params.mode) {
1942 			case MGSL_MODE_ASYNC:
1943 				rx_async(info);
1944 				break;
1945 			case MGSL_MODE_HDLC:
1946 				while(rx_get_frame(info));
1947 				break;
1948 			case MGSL_MODE_RAW:
1949 			case MGSL_MODE_MONOSYNC:
1950 			case MGSL_MODE_BISYNC:
1951 			case MGSL_MODE_XSYNC:
1952 				while(rx_get_buf(info));
1953 				break;
1954 			}
1955 			/* restart receiver if rx DMA buffers exhausted */
1956 			if (info->rx_restart)
1957 				rx_start(info);
1958 			break;
1959 		case BH_TRANSMIT:
1960 			bh_transmit(info);
1961 			break;
1962 		case BH_STATUS:
1963 			DBGBH(("%s bh status\n", info->device_name));
1964 			info->ri_chkcount = 0;
1965 			info->dsr_chkcount = 0;
1966 			info->dcd_chkcount = 0;
1967 			info->cts_chkcount = 0;
1968 			break;
1969 		default:
1970 			DBGBH(("%s unknown action\n", info->device_name));
1971 			break;
1972 		}
1973 	}
1974 	DBGBH(("%s bh_handler exit\n", info->device_name));
1975 }
1976 
1977 static void bh_transmit(struct slgt_info *info)
1978 {
1979 	struct tty_struct *tty = info->port.tty;
1980 
1981 	DBGBH(("%s bh_transmit\n", info->device_name));
1982 	if (tty)
1983 		tty_wakeup(tty);
1984 }
1985 
1986 static void dsr_change(struct slgt_info *info, unsigned short status)
1987 {
1988 	if (status & BIT3) {
1989 		info->signals |= SerialSignal_DSR;
1990 		info->input_signal_events.dsr_up++;
1991 	} else {
1992 		info->signals &= ~SerialSignal_DSR;
1993 		info->input_signal_events.dsr_down++;
1994 	}
1995 	DBGISR(("dsr_change %s signals=%04X\n", info->device_name, info->signals));
1996 	if ((info->dsr_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
1997 		slgt_irq_off(info, IRQ_DSR);
1998 		return;
1999 	}
2000 	info->icount.dsr++;
2001 	wake_up_interruptible(&info->status_event_wait_q);
2002 	wake_up_interruptible(&info->event_wait_q);
2003 	info->pending_bh |= BH_STATUS;
2004 }
2005 
2006 static void cts_change(struct slgt_info *info, unsigned short status)
2007 {
2008 	if (status & BIT2) {
2009 		info->signals |= SerialSignal_CTS;
2010 		info->input_signal_events.cts_up++;
2011 	} else {
2012 		info->signals &= ~SerialSignal_CTS;
2013 		info->input_signal_events.cts_down++;
2014 	}
2015 	DBGISR(("cts_change %s signals=%04X\n", info->device_name, info->signals));
2016 	if ((info->cts_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2017 		slgt_irq_off(info, IRQ_CTS);
2018 		return;
2019 	}
2020 	info->icount.cts++;
2021 	wake_up_interruptible(&info->status_event_wait_q);
2022 	wake_up_interruptible(&info->event_wait_q);
2023 	info->pending_bh |= BH_STATUS;
2024 
2025 	if (tty_port_cts_enabled(&info->port)) {
2026 		if (info->port.tty) {
2027 			if (info->port.tty->hw_stopped) {
2028 				if (info->signals & SerialSignal_CTS) {
2029 		 			info->port.tty->hw_stopped = 0;
2030 					info->pending_bh |= BH_TRANSMIT;
2031 					return;
2032 				}
2033 			} else {
2034 				if (!(info->signals & SerialSignal_CTS))
2035 		 			info->port.tty->hw_stopped = 1;
2036 			}
2037 		}
2038 	}
2039 }
2040 
2041 static void dcd_change(struct slgt_info *info, unsigned short status)
2042 {
2043 	if (status & BIT1) {
2044 		info->signals |= SerialSignal_DCD;
2045 		info->input_signal_events.dcd_up++;
2046 	} else {
2047 		info->signals &= ~SerialSignal_DCD;
2048 		info->input_signal_events.dcd_down++;
2049 	}
2050 	DBGISR(("dcd_change %s signals=%04X\n", info->device_name, info->signals));
2051 	if ((info->dcd_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2052 		slgt_irq_off(info, IRQ_DCD);
2053 		return;
2054 	}
2055 	info->icount.dcd++;
2056 #if SYNCLINK_GENERIC_HDLC
2057 	if (info->netcount) {
2058 		if (info->signals & SerialSignal_DCD)
2059 			netif_carrier_on(info->netdev);
2060 		else
2061 			netif_carrier_off(info->netdev);
2062 	}
2063 #endif
2064 	wake_up_interruptible(&info->status_event_wait_q);
2065 	wake_up_interruptible(&info->event_wait_q);
2066 	info->pending_bh |= BH_STATUS;
2067 
2068 	if (tty_port_check_carrier(&info->port)) {
2069 		if (info->signals & SerialSignal_DCD)
2070 			wake_up_interruptible(&info->port.open_wait);
2071 		else {
2072 			if (info->port.tty)
2073 				tty_hangup(info->port.tty);
2074 		}
2075 	}
2076 }
2077 
2078 static void ri_change(struct slgt_info *info, unsigned short status)
2079 {
2080 	if (status & BIT0) {
2081 		info->signals |= SerialSignal_RI;
2082 		info->input_signal_events.ri_up++;
2083 	} else {
2084 		info->signals &= ~SerialSignal_RI;
2085 		info->input_signal_events.ri_down++;
2086 	}
2087 	DBGISR(("ri_change %s signals=%04X\n", info->device_name, info->signals));
2088 	if ((info->ri_chkcount)++ == IO_PIN_SHUTDOWN_LIMIT) {
2089 		slgt_irq_off(info, IRQ_RI);
2090 		return;
2091 	}
2092 	info->icount.rng++;
2093 	wake_up_interruptible(&info->status_event_wait_q);
2094 	wake_up_interruptible(&info->event_wait_q);
2095 	info->pending_bh |= BH_STATUS;
2096 }
2097 
2098 static void isr_rxdata(struct slgt_info *info)
2099 {
2100 	unsigned int count = info->rbuf_fill_count;
2101 	unsigned int i = info->rbuf_fill_index;
2102 	unsigned short reg;
2103 
2104 	while (rd_reg16(info, SSR) & IRQ_RXDATA) {
2105 		reg = rd_reg16(info, RDR);
2106 		DBGISR(("isr_rxdata %s RDR=%04X\n", info->device_name, reg));
2107 		if (desc_complete(info->rbufs[i])) {
2108 			/* all buffers full */
2109 			rx_stop(info);
2110 			info->rx_restart = 1;
2111 			continue;
2112 		}
2113 		info->rbufs[i].buf[count++] = (unsigned char)reg;
2114 		/* async mode saves status byte to buffer for each data byte */
2115 		if (info->params.mode == MGSL_MODE_ASYNC)
2116 			info->rbufs[i].buf[count++] = (unsigned char)(reg >> 8);
2117 		if (count == info->rbuf_fill_level || (reg & BIT10)) {
2118 			/* buffer full or end of frame */
2119 			set_desc_count(info->rbufs[i], count);
2120 			set_desc_status(info->rbufs[i], BIT15 | (reg >> 8));
2121 			info->rbuf_fill_count = count = 0;
2122 			if (++i == info->rbuf_count)
2123 				i = 0;
2124 			info->pending_bh |= BH_RECEIVE;
2125 		}
2126 	}
2127 
2128 	info->rbuf_fill_index = i;
2129 	info->rbuf_fill_count = count;
2130 }
2131 
2132 static void isr_serial(struct slgt_info *info)
2133 {
2134 	unsigned short status = rd_reg16(info, SSR);
2135 
2136 	DBGISR(("%s isr_serial status=%04X\n", info->device_name, status));
2137 
2138 	wr_reg16(info, SSR, status); /* clear pending */
2139 
2140 	info->irq_occurred = true;
2141 
2142 	if (info->params.mode == MGSL_MODE_ASYNC) {
2143 		if (status & IRQ_TXIDLE) {
2144 			if (info->tx_active)
2145 				isr_txeom(info, status);
2146 		}
2147 		if (info->rx_pio && (status & IRQ_RXDATA))
2148 			isr_rxdata(info);
2149 		if ((status & IRQ_RXBREAK) && (status & RXBREAK)) {
2150 			info->icount.brk++;
2151 			/* process break detection if tty control allows */
2152 			if (info->port.tty) {
2153 				if (!(status & info->ignore_status_mask)) {
2154 					if (info->read_status_mask & MASK_BREAK) {
2155 						tty_insert_flip_char(&info->port, 0, TTY_BREAK);
2156 						if (info->port.flags & ASYNC_SAK)
2157 							do_SAK(info->port.tty);
2158 					}
2159 				}
2160 			}
2161 		}
2162 	} else {
2163 		if (status & (IRQ_TXIDLE + IRQ_TXUNDER))
2164 			isr_txeom(info, status);
2165 		if (info->rx_pio && (status & IRQ_RXDATA))
2166 			isr_rxdata(info);
2167 		if (status & IRQ_RXIDLE) {
2168 			if (status & RXIDLE)
2169 				info->icount.rxidle++;
2170 			else
2171 				info->icount.exithunt++;
2172 			wake_up_interruptible(&info->event_wait_q);
2173 		}
2174 
2175 		if (status & IRQ_RXOVER)
2176 			rx_start(info);
2177 	}
2178 
2179 	if (status & IRQ_DSR)
2180 		dsr_change(info, status);
2181 	if (status & IRQ_CTS)
2182 		cts_change(info, status);
2183 	if (status & IRQ_DCD)
2184 		dcd_change(info, status);
2185 	if (status & IRQ_RI)
2186 		ri_change(info, status);
2187 }
2188 
2189 static void isr_rdma(struct slgt_info *info)
2190 {
2191 	unsigned int status = rd_reg32(info, RDCSR);
2192 
2193 	DBGISR(("%s isr_rdma status=%08x\n", info->device_name, status));
2194 
2195 	/* RDCSR (rx DMA control/status)
2196 	 *
2197 	 * 31..07  reserved
2198 	 * 06      save status byte to DMA buffer
2199 	 * 05      error
2200 	 * 04      eol (end of list)
2201 	 * 03      eob (end of buffer)
2202 	 * 02      IRQ enable
2203 	 * 01      reset
2204 	 * 00      enable
2205 	 */
2206 	wr_reg32(info, RDCSR, status);	/* clear pending */
2207 
2208 	if (status & (BIT5 + BIT4)) {
2209 		DBGISR(("%s isr_rdma rx_restart=1\n", info->device_name));
2210 		info->rx_restart = true;
2211 	}
2212 	info->pending_bh |= BH_RECEIVE;
2213 }
2214 
2215 static void isr_tdma(struct slgt_info *info)
2216 {
2217 	unsigned int status = rd_reg32(info, TDCSR);
2218 
2219 	DBGISR(("%s isr_tdma status=%08x\n", info->device_name, status));
2220 
2221 	/* TDCSR (tx DMA control/status)
2222 	 *
2223 	 * 31..06  reserved
2224 	 * 05      error
2225 	 * 04      eol (end of list)
2226 	 * 03      eob (end of buffer)
2227 	 * 02      IRQ enable
2228 	 * 01      reset
2229 	 * 00      enable
2230 	 */
2231 	wr_reg32(info, TDCSR, status);	/* clear pending */
2232 
2233 	if (status & (BIT5 + BIT4 + BIT3)) {
2234 		// another transmit buffer has completed
2235 		// run bottom half to get more send data from user
2236 		info->pending_bh |= BH_TRANSMIT;
2237 	}
2238 }
2239 
2240 /*
2241  * return true if there are unsent tx DMA buffers, otherwise false
2242  *
2243  * if there are unsent buffers then info->tbuf_start
2244  * is set to index of first unsent buffer
2245  */
2246 static bool unsent_tbufs(struct slgt_info *info)
2247 {
2248 	unsigned int i = info->tbuf_current;
2249 	bool rc = false;
2250 
2251 	/*
2252 	 * search backwards from last loaded buffer (precedes tbuf_current)
2253 	 * for first unsent buffer (desc_count > 0)
2254 	 */
2255 
2256 	do {
2257 		if (i)
2258 			i--;
2259 		else
2260 			i = info->tbuf_count - 1;
2261 		if (!desc_count(info->tbufs[i]))
2262 			break;
2263 		info->tbuf_start = i;
2264 		rc = true;
2265 	} while (i != info->tbuf_current);
2266 
2267 	return rc;
2268 }
2269 
2270 static void isr_txeom(struct slgt_info *info, unsigned short status)
2271 {
2272 	DBGISR(("%s txeom status=%04x\n", info->device_name, status));
2273 
2274 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
2275 	tdma_reset(info);
2276 	if (status & IRQ_TXUNDER) {
2277 		unsigned short val = rd_reg16(info, TCR);
2278 		wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
2279 		wr_reg16(info, TCR, val); /* clear reset bit */
2280 	}
2281 
2282 	if (info->tx_active) {
2283 		if (info->params.mode != MGSL_MODE_ASYNC) {
2284 			if (status & IRQ_TXUNDER)
2285 				info->icount.txunder++;
2286 			else if (status & IRQ_TXIDLE)
2287 				info->icount.txok++;
2288 		}
2289 
2290 		if (unsent_tbufs(info)) {
2291 			tx_start(info);
2292 			update_tx_timer(info);
2293 			return;
2294 		}
2295 		info->tx_active = false;
2296 
2297 		del_timer(&info->tx_timer);
2298 
2299 		if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done) {
2300 			info->signals &= ~SerialSignal_RTS;
2301 			info->drop_rts_on_tx_done = false;
2302 			set_signals(info);
2303 		}
2304 
2305 #if SYNCLINK_GENERIC_HDLC
2306 		if (info->netcount)
2307 			hdlcdev_tx_done(info);
2308 		else
2309 #endif
2310 		{
2311 			if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
2312 				tx_stop(info);
2313 				return;
2314 			}
2315 			info->pending_bh |= BH_TRANSMIT;
2316 		}
2317 	}
2318 }
2319 
2320 static void isr_gpio(struct slgt_info *info, unsigned int changed, unsigned int state)
2321 {
2322 	struct cond_wait *w, *prev;
2323 
2324 	/* wake processes waiting for specific transitions */
2325 	for (w = info->gpio_wait_q, prev = NULL ; w != NULL ; w = w->next) {
2326 		if (w->data & changed) {
2327 			w->data = state;
2328 			wake_up_interruptible(&w->q);
2329 			if (prev != NULL)
2330 				prev->next = w->next;
2331 			else
2332 				info->gpio_wait_q = w->next;
2333 		} else
2334 			prev = w;
2335 	}
2336 }
2337 
2338 /* interrupt service routine
2339  *
2340  * 	irq	interrupt number
2341  * 	dev_id	device ID supplied during interrupt registration
2342  */
2343 static irqreturn_t slgt_interrupt(int dummy, void *dev_id)
2344 {
2345 	struct slgt_info *info = dev_id;
2346 	unsigned int gsr;
2347 	unsigned int i;
2348 
2349 	DBGISR(("slgt_interrupt irq=%d entry\n", info->irq_level));
2350 
2351 	while((gsr = rd_reg32(info, GSR) & 0xffffff00)) {
2352 		DBGISR(("%s gsr=%08x\n", info->device_name, gsr));
2353 		info->irq_occurred = true;
2354 		for(i=0; i < info->port_count ; i++) {
2355 			if (info->port_array[i] == NULL)
2356 				continue;
2357 			spin_lock(&info->port_array[i]->lock);
2358 			if (gsr & (BIT8 << i))
2359 				isr_serial(info->port_array[i]);
2360 			if (gsr & (BIT16 << (i*2)))
2361 				isr_rdma(info->port_array[i]);
2362 			if (gsr & (BIT17 << (i*2)))
2363 				isr_tdma(info->port_array[i]);
2364 			spin_unlock(&info->port_array[i]->lock);
2365 		}
2366 	}
2367 
2368 	if (info->gpio_present) {
2369 		unsigned int state;
2370 		unsigned int changed;
2371 		spin_lock(&info->lock);
2372 		while ((changed = rd_reg32(info, IOSR)) != 0) {
2373 			DBGISR(("%s iosr=%08x\n", info->device_name, changed));
2374 			/* read latched state of GPIO signals */
2375 			state = rd_reg32(info, IOVR);
2376 			/* clear pending GPIO interrupt bits */
2377 			wr_reg32(info, IOSR, changed);
2378 			for (i=0 ; i < info->port_count ; i++) {
2379 				if (info->port_array[i] != NULL)
2380 					isr_gpio(info->port_array[i], changed, state);
2381 			}
2382 		}
2383 		spin_unlock(&info->lock);
2384 	}
2385 
2386 	for(i=0; i < info->port_count ; i++) {
2387 		struct slgt_info *port = info->port_array[i];
2388 		if (port == NULL)
2389 			continue;
2390 		spin_lock(&port->lock);
2391 		if ((port->port.count || port->netcount) &&
2392 		    port->pending_bh && !port->bh_running &&
2393 		    !port->bh_requested) {
2394 			DBGISR(("%s bh queued\n", port->device_name));
2395 			schedule_work(&port->task);
2396 			port->bh_requested = true;
2397 		}
2398 		spin_unlock(&port->lock);
2399 	}
2400 
2401 	DBGISR(("slgt_interrupt irq=%d exit\n", info->irq_level));
2402 	return IRQ_HANDLED;
2403 }
2404 
2405 static int startup(struct slgt_info *info)
2406 {
2407 	DBGINFO(("%s startup\n", info->device_name));
2408 
2409 	if (tty_port_initialized(&info->port))
2410 		return 0;
2411 
2412 	if (!info->tx_buf) {
2413 		info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
2414 		if (!info->tx_buf) {
2415 			DBGERR(("%s can't allocate tx buffer\n", info->device_name));
2416 			return -ENOMEM;
2417 		}
2418 	}
2419 
2420 	info->pending_bh = 0;
2421 
2422 	memset(&info->icount, 0, sizeof(info->icount));
2423 
2424 	/* program hardware for current parameters */
2425 	change_params(info);
2426 
2427 	if (info->port.tty)
2428 		clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
2429 
2430 	tty_port_set_initialized(&info->port, 1);
2431 
2432 	return 0;
2433 }
2434 
2435 /*
2436  *  called by close() and hangup() to shutdown hardware
2437  */
2438 static void shutdown(struct slgt_info *info)
2439 {
2440 	unsigned long flags;
2441 
2442 	if (!tty_port_initialized(&info->port))
2443 		return;
2444 
2445 	DBGINFO(("%s shutdown\n", info->device_name));
2446 
2447 	/* clear status wait queue because status changes */
2448 	/* can't happen after shutting down the hardware */
2449 	wake_up_interruptible(&info->status_event_wait_q);
2450 	wake_up_interruptible(&info->event_wait_q);
2451 
2452 	del_timer_sync(&info->tx_timer);
2453 	del_timer_sync(&info->rx_timer);
2454 
2455 	kfree(info->tx_buf);
2456 	info->tx_buf = NULL;
2457 
2458 	spin_lock_irqsave(&info->lock,flags);
2459 
2460 	tx_stop(info);
2461 	rx_stop(info);
2462 
2463 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
2464 
2465  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
2466 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2467 		set_signals(info);
2468 	}
2469 
2470 	flush_cond_wait(&info->gpio_wait_q);
2471 
2472 	spin_unlock_irqrestore(&info->lock,flags);
2473 
2474 	if (info->port.tty)
2475 		set_bit(TTY_IO_ERROR, &info->port.tty->flags);
2476 
2477 	tty_port_set_initialized(&info->port, 0);
2478 }
2479 
2480 static void program_hw(struct slgt_info *info)
2481 {
2482 	unsigned long flags;
2483 
2484 	spin_lock_irqsave(&info->lock,flags);
2485 
2486 	rx_stop(info);
2487 	tx_stop(info);
2488 
2489 	if (info->params.mode != MGSL_MODE_ASYNC ||
2490 	    info->netcount)
2491 		sync_mode(info);
2492 	else
2493 		async_mode(info);
2494 
2495 	set_signals(info);
2496 
2497 	info->dcd_chkcount = 0;
2498 	info->cts_chkcount = 0;
2499 	info->ri_chkcount = 0;
2500 	info->dsr_chkcount = 0;
2501 
2502 	slgt_irq_on(info, IRQ_DCD | IRQ_CTS | IRQ_DSR | IRQ_RI);
2503 	get_signals(info);
2504 
2505 	if (info->netcount ||
2506 	    (info->port.tty && info->port.tty->termios.c_cflag & CREAD))
2507 		rx_start(info);
2508 
2509 	spin_unlock_irqrestore(&info->lock,flags);
2510 }
2511 
2512 /*
2513  * reconfigure adapter based on new parameters
2514  */
2515 static void change_params(struct slgt_info *info)
2516 {
2517 	unsigned cflag;
2518 	int bits_per_char;
2519 
2520 	if (!info->port.tty)
2521 		return;
2522 	DBGINFO(("%s change_params\n", info->device_name));
2523 
2524 	cflag = info->port.tty->termios.c_cflag;
2525 
2526 	/* if B0 rate (hangup) specified then negate RTS and DTR */
2527 	/* otherwise assert RTS and DTR */
2528  	if (cflag & CBAUD)
2529 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
2530 	else
2531 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
2532 
2533 	/* byte size and parity */
2534 
2535 	switch (cflag & CSIZE) {
2536 	case CS5: info->params.data_bits = 5; break;
2537 	case CS6: info->params.data_bits = 6; break;
2538 	case CS7: info->params.data_bits = 7; break;
2539 	case CS8: info->params.data_bits = 8; break;
2540 	default:  info->params.data_bits = 7; break;
2541 	}
2542 
2543 	info->params.stop_bits = (cflag & CSTOPB) ? 2 : 1;
2544 
2545 	if (cflag & PARENB)
2546 		info->params.parity = (cflag & PARODD) ? ASYNC_PARITY_ODD : ASYNC_PARITY_EVEN;
2547 	else
2548 		info->params.parity = ASYNC_PARITY_NONE;
2549 
2550 	/* calculate number of jiffies to transmit a full
2551 	 * FIFO (32 bytes) at specified data rate
2552 	 */
2553 	bits_per_char = info->params.data_bits +
2554 			info->params.stop_bits + 1;
2555 
2556 	info->params.data_rate = tty_get_baud_rate(info->port.tty);
2557 
2558 	if (info->params.data_rate) {
2559 		info->timeout = (32*HZ*bits_per_char) /
2560 				info->params.data_rate;
2561 	}
2562 	info->timeout += HZ/50;		/* Add .02 seconds of slop */
2563 
2564 	tty_port_set_cts_flow(&info->port, cflag & CRTSCTS);
2565 	tty_port_set_check_carrier(&info->port, ~cflag & CLOCAL);
2566 
2567 	/* process tty input control flags */
2568 
2569 	info->read_status_mask = IRQ_RXOVER;
2570 	if (I_INPCK(info->port.tty))
2571 		info->read_status_mask |= MASK_PARITY | MASK_FRAMING;
2572  	if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
2573  		info->read_status_mask |= MASK_BREAK;
2574 	if (I_IGNPAR(info->port.tty))
2575 		info->ignore_status_mask |= MASK_PARITY | MASK_FRAMING;
2576 	if (I_IGNBRK(info->port.tty)) {
2577 		info->ignore_status_mask |= MASK_BREAK;
2578 		/* If ignoring parity and break indicators, ignore
2579 		 * overruns too.  (For real raw support).
2580 		 */
2581 		if (I_IGNPAR(info->port.tty))
2582 			info->ignore_status_mask |= MASK_OVERRUN;
2583 	}
2584 
2585 	program_hw(info);
2586 }
2587 
2588 static int get_stats(struct slgt_info *info, struct mgsl_icount __user *user_icount)
2589 {
2590 	DBGINFO(("%s get_stats\n",  info->device_name));
2591 	if (!user_icount) {
2592 		memset(&info->icount, 0, sizeof(info->icount));
2593 	} else {
2594 		if (copy_to_user(user_icount, &info->icount, sizeof(struct mgsl_icount)))
2595 			return -EFAULT;
2596 	}
2597 	return 0;
2598 }
2599 
2600 static int get_params(struct slgt_info *info, MGSL_PARAMS __user *user_params)
2601 {
2602 	DBGINFO(("%s get_params\n", info->device_name));
2603 	if (copy_to_user(user_params, &info->params, sizeof(MGSL_PARAMS)))
2604 		return -EFAULT;
2605 	return 0;
2606 }
2607 
2608 static int set_params(struct slgt_info *info, MGSL_PARAMS __user *new_params)
2609 {
2610  	unsigned long flags;
2611 	MGSL_PARAMS tmp_params;
2612 
2613 	DBGINFO(("%s set_params\n", info->device_name));
2614 	if (copy_from_user(&tmp_params, new_params, sizeof(MGSL_PARAMS)))
2615 		return -EFAULT;
2616 
2617 	spin_lock_irqsave(&info->lock, flags);
2618 	if (tmp_params.mode == MGSL_MODE_BASE_CLOCK)
2619 		info->base_clock = tmp_params.clock_speed;
2620 	else
2621 		memcpy(&info->params, &tmp_params, sizeof(MGSL_PARAMS));
2622 	spin_unlock_irqrestore(&info->lock, flags);
2623 
2624 	program_hw(info);
2625 
2626 	return 0;
2627 }
2628 
2629 static int get_txidle(struct slgt_info *info, int __user *idle_mode)
2630 {
2631 	DBGINFO(("%s get_txidle=%d\n", info->device_name, info->idle_mode));
2632 	if (put_user(info->idle_mode, idle_mode))
2633 		return -EFAULT;
2634 	return 0;
2635 }
2636 
2637 static int set_txidle(struct slgt_info *info, int idle_mode)
2638 {
2639  	unsigned long flags;
2640 	DBGINFO(("%s set_txidle(%d)\n", info->device_name, idle_mode));
2641 	spin_lock_irqsave(&info->lock,flags);
2642 	info->idle_mode = idle_mode;
2643 	if (info->params.mode != MGSL_MODE_ASYNC)
2644 		tx_set_idle(info);
2645 	spin_unlock_irqrestore(&info->lock,flags);
2646 	return 0;
2647 }
2648 
2649 static int tx_enable(struct slgt_info *info, int enable)
2650 {
2651  	unsigned long flags;
2652 	DBGINFO(("%s tx_enable(%d)\n", info->device_name, enable));
2653 	spin_lock_irqsave(&info->lock,flags);
2654 	if (enable) {
2655 		if (!info->tx_enabled)
2656 			tx_start(info);
2657 	} else {
2658 		if (info->tx_enabled)
2659 			tx_stop(info);
2660 	}
2661 	spin_unlock_irqrestore(&info->lock,flags);
2662 	return 0;
2663 }
2664 
2665 /*
2666  * abort transmit HDLC frame
2667  */
2668 static int tx_abort(struct slgt_info *info)
2669 {
2670  	unsigned long flags;
2671 	DBGINFO(("%s tx_abort\n", info->device_name));
2672 	spin_lock_irqsave(&info->lock,flags);
2673 	tdma_reset(info);
2674 	spin_unlock_irqrestore(&info->lock,flags);
2675 	return 0;
2676 }
2677 
2678 static int rx_enable(struct slgt_info *info, int enable)
2679 {
2680  	unsigned long flags;
2681 	unsigned int rbuf_fill_level;
2682 	DBGINFO(("%s rx_enable(%08x)\n", info->device_name, enable));
2683 	spin_lock_irqsave(&info->lock,flags);
2684 	/*
2685 	 * enable[31..16] = receive DMA buffer fill level
2686 	 * 0 = noop (leave fill level unchanged)
2687 	 * fill level must be multiple of 4 and <= buffer size
2688 	 */
2689 	rbuf_fill_level = ((unsigned int)enable) >> 16;
2690 	if (rbuf_fill_level) {
2691 		if ((rbuf_fill_level > DMABUFSIZE) || (rbuf_fill_level % 4)) {
2692 			spin_unlock_irqrestore(&info->lock, flags);
2693 			return -EINVAL;
2694 		}
2695 		info->rbuf_fill_level = rbuf_fill_level;
2696 		if (rbuf_fill_level < 128)
2697 			info->rx_pio = 1; /* PIO mode */
2698 		else
2699 			info->rx_pio = 0; /* DMA mode */
2700 		rx_stop(info); /* restart receiver to use new fill level */
2701 	}
2702 
2703 	/*
2704 	 * enable[1..0] = receiver enable command
2705 	 * 0 = disable
2706 	 * 1 = enable
2707 	 * 2 = enable or force hunt mode if already enabled
2708 	 */
2709 	enable &= 3;
2710 	if (enable) {
2711 		if (!info->rx_enabled)
2712 			rx_start(info);
2713 		else if (enable == 2) {
2714 			/* force hunt mode (write 1 to RCR[3]) */
2715 			wr_reg16(info, RCR, rd_reg16(info, RCR) | BIT3);
2716 		}
2717 	} else {
2718 		if (info->rx_enabled)
2719 			rx_stop(info);
2720 	}
2721 	spin_unlock_irqrestore(&info->lock,flags);
2722 	return 0;
2723 }
2724 
2725 /*
2726  *  wait for specified event to occur
2727  */
2728 static int wait_mgsl_event(struct slgt_info *info, int __user *mask_ptr)
2729 {
2730  	unsigned long flags;
2731 	int s;
2732 	int rc=0;
2733 	struct mgsl_icount cprev, cnow;
2734 	int events;
2735 	int mask;
2736 	struct	_input_signal_events oldsigs, newsigs;
2737 	DECLARE_WAITQUEUE(wait, current);
2738 
2739 	if (get_user(mask, mask_ptr))
2740 		return -EFAULT;
2741 
2742 	DBGINFO(("%s wait_mgsl_event(%d)\n", info->device_name, mask));
2743 
2744 	spin_lock_irqsave(&info->lock,flags);
2745 
2746 	/* return immediately if state matches requested events */
2747 	get_signals(info);
2748 	s = info->signals;
2749 
2750 	events = mask &
2751 		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2752  		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2753 		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2754 		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2755 	if (events) {
2756 		spin_unlock_irqrestore(&info->lock,flags);
2757 		goto exit;
2758 	}
2759 
2760 	/* save current irq counts */
2761 	cprev = info->icount;
2762 	oldsigs = info->input_signal_events;
2763 
2764 	/* enable hunt and idle irqs if needed */
2765 	if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
2766 		unsigned short val = rd_reg16(info, SCR);
2767 		if (!(val & IRQ_RXIDLE))
2768 			wr_reg16(info, SCR, (unsigned short)(val | IRQ_RXIDLE));
2769 	}
2770 
2771 	set_current_state(TASK_INTERRUPTIBLE);
2772 	add_wait_queue(&info->event_wait_q, &wait);
2773 
2774 	spin_unlock_irqrestore(&info->lock,flags);
2775 
2776 	for(;;) {
2777 		schedule();
2778 		if (signal_pending(current)) {
2779 			rc = -ERESTARTSYS;
2780 			break;
2781 		}
2782 
2783 		/* get current irq counts */
2784 		spin_lock_irqsave(&info->lock,flags);
2785 		cnow = info->icount;
2786 		newsigs = info->input_signal_events;
2787 		set_current_state(TASK_INTERRUPTIBLE);
2788 		spin_unlock_irqrestore(&info->lock,flags);
2789 
2790 		/* if no change, wait aborted for some reason */
2791 		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2792 		    newsigs.dsr_down == oldsigs.dsr_down &&
2793 		    newsigs.dcd_up   == oldsigs.dcd_up   &&
2794 		    newsigs.dcd_down == oldsigs.dcd_down &&
2795 		    newsigs.cts_up   == oldsigs.cts_up   &&
2796 		    newsigs.cts_down == oldsigs.cts_down &&
2797 		    newsigs.ri_up    == oldsigs.ri_up    &&
2798 		    newsigs.ri_down  == oldsigs.ri_down  &&
2799 		    cnow.exithunt    == cprev.exithunt   &&
2800 		    cnow.rxidle      == cprev.rxidle) {
2801 			rc = -EIO;
2802 			break;
2803 		}
2804 
2805 		events = mask &
2806 			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2807 			  (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2808 			  (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2809 			  (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2810 			  (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2811 			  (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2812 			  (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2813 			  (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2814 			  (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2815 			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2816 		if (events)
2817 			break;
2818 
2819 		cprev = cnow;
2820 		oldsigs = newsigs;
2821 	}
2822 
2823 	remove_wait_queue(&info->event_wait_q, &wait);
2824 	set_current_state(TASK_RUNNING);
2825 
2826 
2827 	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2828 		spin_lock_irqsave(&info->lock,flags);
2829 		if (!waitqueue_active(&info->event_wait_q)) {
2830 			/* disable enable exit hunt mode/idle rcvd IRQs */
2831 			wr_reg16(info, SCR,
2832 				(unsigned short)(rd_reg16(info, SCR) & ~IRQ_RXIDLE));
2833 		}
2834 		spin_unlock_irqrestore(&info->lock,flags);
2835 	}
2836 exit:
2837 	if (rc == 0)
2838 		rc = put_user(events, mask_ptr);
2839 	return rc;
2840 }
2841 
2842 static int get_interface(struct slgt_info *info, int __user *if_mode)
2843 {
2844 	DBGINFO(("%s get_interface=%x\n", info->device_name, info->if_mode));
2845 	if (put_user(info->if_mode, if_mode))
2846 		return -EFAULT;
2847 	return 0;
2848 }
2849 
2850 static int set_interface(struct slgt_info *info, int if_mode)
2851 {
2852  	unsigned long flags;
2853 	unsigned short val;
2854 
2855 	DBGINFO(("%s set_interface=%x)\n", info->device_name, if_mode));
2856 	spin_lock_irqsave(&info->lock,flags);
2857 	info->if_mode = if_mode;
2858 
2859 	msc_set_vcr(info);
2860 
2861 	/* TCR (tx control) 07  1=RTS driver control */
2862 	val = rd_reg16(info, TCR);
2863 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
2864 		val |= BIT7;
2865 	else
2866 		val &= ~BIT7;
2867 	wr_reg16(info, TCR, val);
2868 
2869 	spin_unlock_irqrestore(&info->lock,flags);
2870 	return 0;
2871 }
2872 
2873 static int get_xsync(struct slgt_info *info, int __user *xsync)
2874 {
2875 	DBGINFO(("%s get_xsync=%x\n", info->device_name, info->xsync));
2876 	if (put_user(info->xsync, xsync))
2877 		return -EFAULT;
2878 	return 0;
2879 }
2880 
2881 /*
2882  * set extended sync pattern (1 to 4 bytes) for extended sync mode
2883  *
2884  * sync pattern is contained in least significant bytes of value
2885  * most significant byte of sync pattern is oldest (1st sent/detected)
2886  */
2887 static int set_xsync(struct slgt_info *info, int xsync)
2888 {
2889 	unsigned long flags;
2890 
2891 	DBGINFO(("%s set_xsync=%x)\n", info->device_name, xsync));
2892 	spin_lock_irqsave(&info->lock, flags);
2893 	info->xsync = xsync;
2894 	wr_reg32(info, XSR, xsync);
2895 	spin_unlock_irqrestore(&info->lock, flags);
2896 	return 0;
2897 }
2898 
2899 static int get_xctrl(struct slgt_info *info, int __user *xctrl)
2900 {
2901 	DBGINFO(("%s get_xctrl=%x\n", info->device_name, info->xctrl));
2902 	if (put_user(info->xctrl, xctrl))
2903 		return -EFAULT;
2904 	return 0;
2905 }
2906 
2907 /*
2908  * set extended control options
2909  *
2910  * xctrl[31:19] reserved, must be zero
2911  * xctrl[18:17] extended sync pattern length in bytes
2912  *              00 = 1 byte  in xsr[7:0]
2913  *              01 = 2 bytes in xsr[15:0]
2914  *              10 = 3 bytes in xsr[23:0]
2915  *              11 = 4 bytes in xsr[31:0]
2916  * xctrl[16]    1 = enable terminal count, 0=disabled
2917  * xctrl[15:0]  receive terminal count for fixed length packets
2918  *              value is count minus one (0 = 1 byte packet)
2919  *              when terminal count is reached, receiver
2920  *              automatically returns to hunt mode and receive
2921  *              FIFO contents are flushed to DMA buffers with
2922  *              end of frame (EOF) status
2923  */
2924 static int set_xctrl(struct slgt_info *info, int xctrl)
2925 {
2926 	unsigned long flags;
2927 
2928 	DBGINFO(("%s set_xctrl=%x)\n", info->device_name, xctrl));
2929 	spin_lock_irqsave(&info->lock, flags);
2930 	info->xctrl = xctrl;
2931 	wr_reg32(info, XCR, xctrl);
2932 	spin_unlock_irqrestore(&info->lock, flags);
2933 	return 0;
2934 }
2935 
2936 /*
2937  * set general purpose IO pin state and direction
2938  *
2939  * user_gpio fields:
2940  * state   each bit indicates a pin state
2941  * smask   set bit indicates pin state to set
2942  * dir     each bit indicates a pin direction (0=input, 1=output)
2943  * dmask   set bit indicates pin direction to set
2944  */
2945 static int set_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2946 {
2947  	unsigned long flags;
2948 	struct gpio_desc gpio;
2949 	__u32 data;
2950 
2951 	if (!info->gpio_present)
2952 		return -EINVAL;
2953 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
2954 		return -EFAULT;
2955 	DBGINFO(("%s set_gpio state=%08x smask=%08x dir=%08x dmask=%08x\n",
2956 		 info->device_name, gpio.state, gpio.smask,
2957 		 gpio.dir, gpio.dmask));
2958 
2959 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
2960 	if (gpio.dmask) {
2961 		data = rd_reg32(info, IODR);
2962 		data |= gpio.dmask & gpio.dir;
2963 		data &= ~(gpio.dmask & ~gpio.dir);
2964 		wr_reg32(info, IODR, data);
2965 	}
2966 	if (gpio.smask) {
2967 		data = rd_reg32(info, IOVR);
2968 		data |= gpio.smask & gpio.state;
2969 		data &= ~(gpio.smask & ~gpio.state);
2970 		wr_reg32(info, IOVR, data);
2971 	}
2972 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
2973 
2974 	return 0;
2975 }
2976 
2977 /*
2978  * get general purpose IO pin state and direction
2979  */
2980 static int get_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
2981 {
2982 	struct gpio_desc gpio;
2983 	if (!info->gpio_present)
2984 		return -EINVAL;
2985 	gpio.state = rd_reg32(info, IOVR);
2986 	gpio.smask = 0xffffffff;
2987 	gpio.dir   = rd_reg32(info, IODR);
2988 	gpio.dmask = 0xffffffff;
2989 	if (copy_to_user(user_gpio, &gpio, sizeof(gpio)))
2990 		return -EFAULT;
2991 	DBGINFO(("%s get_gpio state=%08x dir=%08x\n",
2992 		 info->device_name, gpio.state, gpio.dir));
2993 	return 0;
2994 }
2995 
2996 /*
2997  * conditional wait facility
2998  */
2999 static void init_cond_wait(struct cond_wait *w, unsigned int data)
3000 {
3001 	init_waitqueue_head(&w->q);
3002 	init_waitqueue_entry(&w->wait, current);
3003 	w->data = data;
3004 }
3005 
3006 static void add_cond_wait(struct cond_wait **head, struct cond_wait *w)
3007 {
3008 	set_current_state(TASK_INTERRUPTIBLE);
3009 	add_wait_queue(&w->q, &w->wait);
3010 	w->next = *head;
3011 	*head = w;
3012 }
3013 
3014 static void remove_cond_wait(struct cond_wait **head, struct cond_wait *cw)
3015 {
3016 	struct cond_wait *w, *prev;
3017 	remove_wait_queue(&cw->q, &cw->wait);
3018 	set_current_state(TASK_RUNNING);
3019 	for (w = *head, prev = NULL ; w != NULL ; prev = w, w = w->next) {
3020 		if (w == cw) {
3021 			if (prev != NULL)
3022 				prev->next = w->next;
3023 			else
3024 				*head = w->next;
3025 			break;
3026 		}
3027 	}
3028 }
3029 
3030 static void flush_cond_wait(struct cond_wait **head)
3031 {
3032 	while (*head != NULL) {
3033 		wake_up_interruptible(&(*head)->q);
3034 		*head = (*head)->next;
3035 	}
3036 }
3037 
3038 /*
3039  * wait for general purpose I/O pin(s) to enter specified state
3040  *
3041  * user_gpio fields:
3042  * state - bit indicates target pin state
3043  * smask - set bit indicates watched pin
3044  *
3045  * The wait ends when at least one watched pin enters the specified
3046  * state. When 0 (no error) is returned, user_gpio->state is set to the
3047  * state of all GPIO pins when the wait ends.
3048  *
3049  * Note: Each pin may be a dedicated input, dedicated output, or
3050  * configurable input/output. The number and configuration of pins
3051  * varies with the specific adapter model. Only input pins (dedicated
3052  * or configured) can be monitored with this function.
3053  */
3054 static int wait_gpio(struct slgt_info *info, struct gpio_desc __user *user_gpio)
3055 {
3056  	unsigned long flags;
3057 	int rc = 0;
3058 	struct gpio_desc gpio;
3059 	struct cond_wait wait;
3060 	u32 state;
3061 
3062 	if (!info->gpio_present)
3063 		return -EINVAL;
3064 	if (copy_from_user(&gpio, user_gpio, sizeof(gpio)))
3065 		return -EFAULT;
3066 	DBGINFO(("%s wait_gpio() state=%08x smask=%08x\n",
3067 		 info->device_name, gpio.state, gpio.smask));
3068 	/* ignore output pins identified by set IODR bit */
3069 	if ((gpio.smask &= ~rd_reg32(info, IODR)) == 0)
3070 		return -EINVAL;
3071 	init_cond_wait(&wait, gpio.smask);
3072 
3073 	spin_lock_irqsave(&info->port_array[0]->lock, flags);
3074 	/* enable interrupts for watched pins */
3075 	wr_reg32(info, IOER, rd_reg32(info, IOER) | gpio.smask);
3076 	/* get current pin states */
3077 	state = rd_reg32(info, IOVR);
3078 
3079 	if (gpio.smask & ~(state ^ gpio.state)) {
3080 		/* already in target state */
3081 		gpio.state = state;
3082 	} else {
3083 		/* wait for target state */
3084 		add_cond_wait(&info->gpio_wait_q, &wait);
3085 		spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3086 		schedule();
3087 		if (signal_pending(current))
3088 			rc = -ERESTARTSYS;
3089 		else
3090 			gpio.state = wait.data;
3091 		spin_lock_irqsave(&info->port_array[0]->lock, flags);
3092 		remove_cond_wait(&info->gpio_wait_q, &wait);
3093 	}
3094 
3095 	/* disable all GPIO interrupts if no waiting processes */
3096 	if (info->gpio_wait_q == NULL)
3097 		wr_reg32(info, IOER, 0);
3098 	spin_unlock_irqrestore(&info->port_array[0]->lock, flags);
3099 
3100 	if ((rc == 0) && copy_to_user(user_gpio, &gpio, sizeof(gpio)))
3101 		rc = -EFAULT;
3102 	return rc;
3103 }
3104 
3105 static int modem_input_wait(struct slgt_info *info,int arg)
3106 {
3107  	unsigned long flags;
3108 	int rc;
3109 	struct mgsl_icount cprev, cnow;
3110 	DECLARE_WAITQUEUE(wait, current);
3111 
3112 	/* save current irq counts */
3113 	spin_lock_irqsave(&info->lock,flags);
3114 	cprev = info->icount;
3115 	add_wait_queue(&info->status_event_wait_q, &wait);
3116 	set_current_state(TASK_INTERRUPTIBLE);
3117 	spin_unlock_irqrestore(&info->lock,flags);
3118 
3119 	for(;;) {
3120 		schedule();
3121 		if (signal_pending(current)) {
3122 			rc = -ERESTARTSYS;
3123 			break;
3124 		}
3125 
3126 		/* get new irq counts */
3127 		spin_lock_irqsave(&info->lock,flags);
3128 		cnow = info->icount;
3129 		set_current_state(TASK_INTERRUPTIBLE);
3130 		spin_unlock_irqrestore(&info->lock,flags);
3131 
3132 		/* if no change, wait aborted for some reason */
3133 		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
3134 		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
3135 			rc = -EIO;
3136 			break;
3137 		}
3138 
3139 		/* check for change in caller specified modem input */
3140 		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
3141 		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
3142 		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
3143 		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
3144 			rc = 0;
3145 			break;
3146 		}
3147 
3148 		cprev = cnow;
3149 	}
3150 	remove_wait_queue(&info->status_event_wait_q, &wait);
3151 	set_current_state(TASK_RUNNING);
3152 	return rc;
3153 }
3154 
3155 /*
3156  *  return state of serial control and status signals
3157  */
3158 static int tiocmget(struct tty_struct *tty)
3159 {
3160 	struct slgt_info *info = tty->driver_data;
3161 	unsigned int result;
3162  	unsigned long flags;
3163 
3164 	spin_lock_irqsave(&info->lock,flags);
3165  	get_signals(info);
3166 	spin_unlock_irqrestore(&info->lock,flags);
3167 
3168 	result = ((info->signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
3169 		((info->signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
3170 		((info->signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
3171 		((info->signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
3172 		((info->signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
3173 		((info->signals & SerialSignal_CTS) ? TIOCM_CTS:0);
3174 
3175 	DBGINFO(("%s tiocmget value=%08X\n", info->device_name, result));
3176 	return result;
3177 }
3178 
3179 /*
3180  * set modem control signals (DTR/RTS)
3181  *
3182  * 	cmd	signal command: TIOCMBIS = set bit TIOCMBIC = clear bit
3183  *		TIOCMSET = set/clear signal values
3184  * 	value	bit mask for command
3185  */
3186 static int tiocmset(struct tty_struct *tty,
3187 		    unsigned int set, unsigned int clear)
3188 {
3189 	struct slgt_info *info = tty->driver_data;
3190  	unsigned long flags;
3191 
3192 	DBGINFO(("%s tiocmset(%x,%x)\n", info->device_name, set, clear));
3193 
3194 	if (set & TIOCM_RTS)
3195 		info->signals |= SerialSignal_RTS;
3196 	if (set & TIOCM_DTR)
3197 		info->signals |= SerialSignal_DTR;
3198 	if (clear & TIOCM_RTS)
3199 		info->signals &= ~SerialSignal_RTS;
3200 	if (clear & TIOCM_DTR)
3201 		info->signals &= ~SerialSignal_DTR;
3202 
3203 	spin_lock_irqsave(&info->lock,flags);
3204  	set_signals(info);
3205 	spin_unlock_irqrestore(&info->lock,flags);
3206 	return 0;
3207 }
3208 
3209 static int carrier_raised(struct tty_port *port)
3210 {
3211 	unsigned long flags;
3212 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3213 
3214 	spin_lock_irqsave(&info->lock,flags);
3215  	get_signals(info);
3216 	spin_unlock_irqrestore(&info->lock,flags);
3217 	return (info->signals & SerialSignal_DCD) ? 1 : 0;
3218 }
3219 
3220 static void dtr_rts(struct tty_port *port, int on)
3221 {
3222 	unsigned long flags;
3223 	struct slgt_info *info = container_of(port, struct slgt_info, port);
3224 
3225 	spin_lock_irqsave(&info->lock,flags);
3226 	if (on)
3227 		info->signals |= SerialSignal_RTS | SerialSignal_DTR;
3228 	else
3229 		info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
3230  	set_signals(info);
3231 	spin_unlock_irqrestore(&info->lock,flags);
3232 }
3233 
3234 
3235 /*
3236  *  block current process until the device is ready to open
3237  */
3238 static int block_til_ready(struct tty_struct *tty, struct file *filp,
3239 			   struct slgt_info *info)
3240 {
3241 	DECLARE_WAITQUEUE(wait, current);
3242 	int		retval;
3243 	bool		do_clocal = false;
3244 	unsigned long	flags;
3245 	int		cd;
3246 	struct tty_port *port = &info->port;
3247 
3248 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
3249 
3250 	if (filp->f_flags & O_NONBLOCK || tty_io_error(tty)) {
3251 		/* nonblock mode is set or port is not enabled */
3252 		tty_port_set_active(port, 1);
3253 		return 0;
3254 	}
3255 
3256 	if (C_CLOCAL(tty))
3257 		do_clocal = true;
3258 
3259 	/* Wait for carrier detect and the line to become
3260 	 * free (i.e., not in use by the callout).  While we are in
3261 	 * this loop, port->count is dropped by one, so that
3262 	 * close() knows when to free things.  We restore it upon
3263 	 * exit, either normal or abnormal.
3264 	 */
3265 
3266 	retval = 0;
3267 	add_wait_queue(&port->open_wait, &wait);
3268 
3269 	spin_lock_irqsave(&info->lock, flags);
3270 	port->count--;
3271 	spin_unlock_irqrestore(&info->lock, flags);
3272 	port->blocked_open++;
3273 
3274 	while (1) {
3275 		if (C_BAUD(tty) && tty_port_initialized(port))
3276 			tty_port_raise_dtr_rts(port);
3277 
3278 		set_current_state(TASK_INTERRUPTIBLE);
3279 
3280 		if (tty_hung_up_p(filp) || !tty_port_initialized(port)) {
3281 			retval = (port->flags & ASYNC_HUP_NOTIFY) ?
3282 					-EAGAIN : -ERESTARTSYS;
3283 			break;
3284 		}
3285 
3286 		cd = tty_port_carrier_raised(port);
3287 		if (do_clocal || cd)
3288 			break;
3289 
3290 		if (signal_pending(current)) {
3291 			retval = -ERESTARTSYS;
3292 			break;
3293 		}
3294 
3295 		DBGINFO(("%s block_til_ready wait\n", tty->driver->name));
3296 		tty_unlock(tty);
3297 		schedule();
3298 		tty_lock(tty);
3299 	}
3300 
3301 	set_current_state(TASK_RUNNING);
3302 	remove_wait_queue(&port->open_wait, &wait);
3303 
3304 	if (!tty_hung_up_p(filp))
3305 		port->count++;
3306 	port->blocked_open--;
3307 
3308 	if (!retval)
3309 		tty_port_set_active(port, 1);
3310 
3311 	DBGINFO(("%s block_til_ready ready, rc=%d\n", tty->driver->name, retval));
3312 	return retval;
3313 }
3314 
3315 /*
3316  * allocate buffers used for calling line discipline receive_buf
3317  * directly in synchronous mode
3318  * note: add 5 bytes to max frame size to allow appending
3319  * 32-bit CRC and status byte when configured to do so
3320  */
3321 static int alloc_tmp_rbuf(struct slgt_info *info)
3322 {
3323 	info->tmp_rbuf = kmalloc(info->max_frame_size + 5, GFP_KERNEL);
3324 	if (info->tmp_rbuf == NULL)
3325 		return -ENOMEM;
3326 	/* unused flag buffer to satisfy receive_buf calling interface */
3327 	info->flag_buf = kzalloc(info->max_frame_size + 5, GFP_KERNEL);
3328 	if (!info->flag_buf) {
3329 		kfree(info->tmp_rbuf);
3330 		info->tmp_rbuf = NULL;
3331 		return -ENOMEM;
3332 	}
3333 	return 0;
3334 }
3335 
3336 static void free_tmp_rbuf(struct slgt_info *info)
3337 {
3338 	kfree(info->tmp_rbuf);
3339 	info->tmp_rbuf = NULL;
3340 	kfree(info->flag_buf);
3341 	info->flag_buf = NULL;
3342 }
3343 
3344 /*
3345  * allocate DMA descriptor lists.
3346  */
3347 static int alloc_desc(struct slgt_info *info)
3348 {
3349 	unsigned int i;
3350 	unsigned int pbufs;
3351 
3352 	/* allocate memory to hold descriptor lists */
3353 	info->bufs = pci_zalloc_consistent(info->pdev, DESC_LIST_SIZE,
3354 					   &info->bufs_dma_addr);
3355 	if (info->bufs == NULL)
3356 		return -ENOMEM;
3357 
3358 	info->rbufs = (struct slgt_desc*)info->bufs;
3359 	info->tbufs = ((struct slgt_desc*)info->bufs) + info->rbuf_count;
3360 
3361 	pbufs = (unsigned int)info->bufs_dma_addr;
3362 
3363 	/*
3364 	 * Build circular lists of descriptors
3365 	 */
3366 
3367 	for (i=0; i < info->rbuf_count; i++) {
3368 		/* physical address of this descriptor */
3369 		info->rbufs[i].pdesc = pbufs + (i * sizeof(struct slgt_desc));
3370 
3371 		/* physical address of next descriptor */
3372 		if (i == info->rbuf_count - 1)
3373 			info->rbufs[i].next = cpu_to_le32(pbufs);
3374 		else
3375 			info->rbufs[i].next = cpu_to_le32(pbufs + ((i+1) * sizeof(struct slgt_desc)));
3376 		set_desc_count(info->rbufs[i], DMABUFSIZE);
3377 	}
3378 
3379 	for (i=0; i < info->tbuf_count; i++) {
3380 		/* physical address of this descriptor */
3381 		info->tbufs[i].pdesc = pbufs + ((info->rbuf_count + i) * sizeof(struct slgt_desc));
3382 
3383 		/* physical address of next descriptor */
3384 		if (i == info->tbuf_count - 1)
3385 			info->tbufs[i].next = cpu_to_le32(pbufs + info->rbuf_count * sizeof(struct slgt_desc));
3386 		else
3387 			info->tbufs[i].next = cpu_to_le32(pbufs + ((info->rbuf_count + i + 1) * sizeof(struct slgt_desc)));
3388 	}
3389 
3390 	return 0;
3391 }
3392 
3393 static void free_desc(struct slgt_info *info)
3394 {
3395 	if (info->bufs != NULL) {
3396 		pci_free_consistent(info->pdev, DESC_LIST_SIZE, info->bufs, info->bufs_dma_addr);
3397 		info->bufs  = NULL;
3398 		info->rbufs = NULL;
3399 		info->tbufs = NULL;
3400 	}
3401 }
3402 
3403 static int alloc_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3404 {
3405 	int i;
3406 	for (i=0; i < count; i++) {
3407 		if ((bufs[i].buf = pci_alloc_consistent(info->pdev, DMABUFSIZE, &bufs[i].buf_dma_addr)) == NULL)
3408 			return -ENOMEM;
3409 		bufs[i].pbuf  = cpu_to_le32((unsigned int)bufs[i].buf_dma_addr);
3410 	}
3411 	return 0;
3412 }
3413 
3414 static void free_bufs(struct slgt_info *info, struct slgt_desc *bufs, int count)
3415 {
3416 	int i;
3417 	for (i=0; i < count; i++) {
3418 		if (bufs[i].buf == NULL)
3419 			continue;
3420 		pci_free_consistent(info->pdev, DMABUFSIZE, bufs[i].buf, bufs[i].buf_dma_addr);
3421 		bufs[i].buf = NULL;
3422 	}
3423 }
3424 
3425 static int alloc_dma_bufs(struct slgt_info *info)
3426 {
3427 	info->rbuf_count = 32;
3428 	info->tbuf_count = 32;
3429 
3430 	if (alloc_desc(info) < 0 ||
3431 	    alloc_bufs(info, info->rbufs, info->rbuf_count) < 0 ||
3432 	    alloc_bufs(info, info->tbufs, info->tbuf_count) < 0 ||
3433 	    alloc_tmp_rbuf(info) < 0) {
3434 		DBGERR(("%s DMA buffer alloc fail\n", info->device_name));
3435 		return -ENOMEM;
3436 	}
3437 	reset_rbufs(info);
3438 	return 0;
3439 }
3440 
3441 static void free_dma_bufs(struct slgt_info *info)
3442 {
3443 	if (info->bufs) {
3444 		free_bufs(info, info->rbufs, info->rbuf_count);
3445 		free_bufs(info, info->tbufs, info->tbuf_count);
3446 		free_desc(info);
3447 	}
3448 	free_tmp_rbuf(info);
3449 }
3450 
3451 static int claim_resources(struct slgt_info *info)
3452 {
3453 	if (request_mem_region(info->phys_reg_addr, SLGT_REG_SIZE, "synclink_gt") == NULL) {
3454 		DBGERR(("%s reg addr conflict, addr=%08X\n",
3455 			info->device_name, info->phys_reg_addr));
3456 		info->init_error = DiagStatus_AddressConflict;
3457 		goto errout;
3458 	}
3459 	else
3460 		info->reg_addr_requested = true;
3461 
3462 	info->reg_addr = ioremap_nocache(info->phys_reg_addr, SLGT_REG_SIZE);
3463 	if (!info->reg_addr) {
3464 		DBGERR(("%s can't map device registers, addr=%08X\n",
3465 			info->device_name, info->phys_reg_addr));
3466 		info->init_error = DiagStatus_CantAssignPciResources;
3467 		goto errout;
3468 	}
3469 	return 0;
3470 
3471 errout:
3472 	release_resources(info);
3473 	return -ENODEV;
3474 }
3475 
3476 static void release_resources(struct slgt_info *info)
3477 {
3478 	if (info->irq_requested) {
3479 		free_irq(info->irq_level, info);
3480 		info->irq_requested = false;
3481 	}
3482 
3483 	if (info->reg_addr_requested) {
3484 		release_mem_region(info->phys_reg_addr, SLGT_REG_SIZE);
3485 		info->reg_addr_requested = false;
3486 	}
3487 
3488 	if (info->reg_addr) {
3489 		iounmap(info->reg_addr);
3490 		info->reg_addr = NULL;
3491 	}
3492 }
3493 
3494 /* Add the specified device instance data structure to the
3495  * global linked list of devices and increment the device count.
3496  */
3497 static void add_device(struct slgt_info *info)
3498 {
3499 	char *devstr;
3500 
3501 	info->next_device = NULL;
3502 	info->line = slgt_device_count;
3503 	sprintf(info->device_name, "%s%d", tty_dev_prefix, info->line);
3504 
3505 	if (info->line < MAX_DEVICES) {
3506 		if (maxframe[info->line])
3507 			info->max_frame_size = maxframe[info->line];
3508 	}
3509 
3510 	slgt_device_count++;
3511 
3512 	if (!slgt_device_list)
3513 		slgt_device_list = info;
3514 	else {
3515 		struct slgt_info *current_dev = slgt_device_list;
3516 		while(current_dev->next_device)
3517 			current_dev = current_dev->next_device;
3518 		current_dev->next_device = info;
3519 	}
3520 
3521 	if (info->max_frame_size < 4096)
3522 		info->max_frame_size = 4096;
3523 	else if (info->max_frame_size > 65535)
3524 		info->max_frame_size = 65535;
3525 
3526 	switch(info->pdev->device) {
3527 	case SYNCLINK_GT_DEVICE_ID:
3528 		devstr = "GT";
3529 		break;
3530 	case SYNCLINK_GT2_DEVICE_ID:
3531 		devstr = "GT2";
3532 		break;
3533 	case SYNCLINK_GT4_DEVICE_ID:
3534 		devstr = "GT4";
3535 		break;
3536 	case SYNCLINK_AC_DEVICE_ID:
3537 		devstr = "AC";
3538 		info->params.mode = MGSL_MODE_ASYNC;
3539 		break;
3540 	default:
3541 		devstr = "(unknown model)";
3542 	}
3543 	printk("SyncLink %s %s IO=%08x IRQ=%d MaxFrameSize=%u\n",
3544 		devstr, info->device_name, info->phys_reg_addr,
3545 		info->irq_level, info->max_frame_size);
3546 
3547 #if SYNCLINK_GENERIC_HDLC
3548 	hdlcdev_init(info);
3549 #endif
3550 }
3551 
3552 static const struct tty_port_operations slgt_port_ops = {
3553 	.carrier_raised = carrier_raised,
3554 	.dtr_rts = dtr_rts,
3555 };
3556 
3557 /*
3558  *  allocate device instance structure, return NULL on failure
3559  */
3560 static struct slgt_info *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
3561 {
3562 	struct slgt_info *info;
3563 
3564 	info = kzalloc(sizeof(struct slgt_info), GFP_KERNEL);
3565 
3566 	if (!info) {
3567 		DBGERR(("%s device alloc failed adapter=%d port=%d\n",
3568 			driver_name, adapter_num, port_num));
3569 	} else {
3570 		tty_port_init(&info->port);
3571 		info->port.ops = &slgt_port_ops;
3572 		info->magic = MGSL_MAGIC;
3573 		INIT_WORK(&info->task, bh_handler);
3574 		info->max_frame_size = 4096;
3575 		info->base_clock = 14745600;
3576 		info->rbuf_fill_level = DMABUFSIZE;
3577 		info->port.close_delay = 5*HZ/10;
3578 		info->port.closing_wait = 30*HZ;
3579 		init_waitqueue_head(&info->status_event_wait_q);
3580 		init_waitqueue_head(&info->event_wait_q);
3581 		spin_lock_init(&info->netlock);
3582 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
3583 		info->idle_mode = HDLC_TXIDLE_FLAGS;
3584 		info->adapter_num = adapter_num;
3585 		info->port_num = port_num;
3586 
3587 		timer_setup(&info->tx_timer, tx_timeout, 0);
3588 		timer_setup(&info->rx_timer, rx_timeout, 0);
3589 
3590 		/* Copy configuration info to device instance data */
3591 		info->pdev = pdev;
3592 		info->irq_level = pdev->irq;
3593 		info->phys_reg_addr = pci_resource_start(pdev,0);
3594 
3595 		info->bus_type = MGSL_BUS_TYPE_PCI;
3596 		info->irq_flags = IRQF_SHARED;
3597 
3598 		info->init_error = -1; /* assume error, set to 0 on successful init */
3599 	}
3600 
3601 	return info;
3602 }
3603 
3604 static void device_init(int adapter_num, struct pci_dev *pdev)
3605 {
3606 	struct slgt_info *port_array[SLGT_MAX_PORTS];
3607 	int i;
3608 	int port_count = 1;
3609 
3610 	if (pdev->device == SYNCLINK_GT2_DEVICE_ID)
3611 		port_count = 2;
3612 	else if (pdev->device == SYNCLINK_GT4_DEVICE_ID)
3613 		port_count = 4;
3614 
3615 	/* allocate device instances for all ports */
3616 	for (i=0; i < port_count; ++i) {
3617 		port_array[i] = alloc_dev(adapter_num, i, pdev);
3618 		if (port_array[i] == NULL) {
3619 			for (--i; i >= 0; --i) {
3620 				tty_port_destroy(&port_array[i]->port);
3621 				kfree(port_array[i]);
3622 			}
3623 			return;
3624 		}
3625 	}
3626 
3627 	/* give copy of port_array to all ports and add to device list  */
3628 	for (i=0; i < port_count; ++i) {
3629 		memcpy(port_array[i]->port_array, port_array, sizeof(port_array));
3630 		add_device(port_array[i]);
3631 		port_array[i]->port_count = port_count;
3632 		spin_lock_init(&port_array[i]->lock);
3633 	}
3634 
3635 	/* Allocate and claim adapter resources */
3636 	if (!claim_resources(port_array[0])) {
3637 
3638 		alloc_dma_bufs(port_array[0]);
3639 
3640 		/* copy resource information from first port to others */
3641 		for (i = 1; i < port_count; ++i) {
3642 			port_array[i]->irq_level = port_array[0]->irq_level;
3643 			port_array[i]->reg_addr  = port_array[0]->reg_addr;
3644 			alloc_dma_bufs(port_array[i]);
3645 		}
3646 
3647 		if (request_irq(port_array[0]->irq_level,
3648 					slgt_interrupt,
3649 					port_array[0]->irq_flags,
3650 					port_array[0]->device_name,
3651 					port_array[0]) < 0) {
3652 			DBGERR(("%s request_irq failed IRQ=%d\n",
3653 				port_array[0]->device_name,
3654 				port_array[0]->irq_level));
3655 		} else {
3656 			port_array[0]->irq_requested = true;
3657 			adapter_test(port_array[0]);
3658 			for (i=1 ; i < port_count ; i++) {
3659 				port_array[i]->init_error = port_array[0]->init_error;
3660 				port_array[i]->gpio_present = port_array[0]->gpio_present;
3661 			}
3662 		}
3663 	}
3664 
3665 	for (i = 0; i < port_count; ++i) {
3666 		struct slgt_info *info = port_array[i];
3667 		tty_port_register_device(&info->port, serial_driver, info->line,
3668 				&info->pdev->dev);
3669 	}
3670 }
3671 
3672 static int init_one(struct pci_dev *dev,
3673 			      const struct pci_device_id *ent)
3674 {
3675 	if (pci_enable_device(dev)) {
3676 		printk("error enabling pci device %p\n", dev);
3677 		return -EIO;
3678 	}
3679 	pci_set_master(dev);
3680 	device_init(slgt_device_count, dev);
3681 	return 0;
3682 }
3683 
3684 static void remove_one(struct pci_dev *dev)
3685 {
3686 }
3687 
3688 static const struct tty_operations ops = {
3689 	.open = open,
3690 	.close = close,
3691 	.write = write,
3692 	.put_char = put_char,
3693 	.flush_chars = flush_chars,
3694 	.write_room = write_room,
3695 	.chars_in_buffer = chars_in_buffer,
3696 	.flush_buffer = flush_buffer,
3697 	.ioctl = ioctl,
3698 	.compat_ioctl = slgt_compat_ioctl,
3699 	.throttle = throttle,
3700 	.unthrottle = unthrottle,
3701 	.send_xchar = send_xchar,
3702 	.break_ctl = set_break,
3703 	.wait_until_sent = wait_until_sent,
3704 	.set_termios = set_termios,
3705 	.stop = tx_hold,
3706 	.start = tx_release,
3707 	.hangup = hangup,
3708 	.tiocmget = tiocmget,
3709 	.tiocmset = tiocmset,
3710 	.get_icount = get_icount,
3711 	.proc_show = synclink_gt_proc_show,
3712 };
3713 
3714 static void slgt_cleanup(void)
3715 {
3716 	int rc;
3717 	struct slgt_info *info;
3718 	struct slgt_info *tmp;
3719 
3720 	printk(KERN_INFO "unload %s\n", driver_name);
3721 
3722 	if (serial_driver) {
3723 		for (info=slgt_device_list ; info != NULL ; info=info->next_device)
3724 			tty_unregister_device(serial_driver, info->line);
3725 		rc = tty_unregister_driver(serial_driver);
3726 		if (rc)
3727 			DBGERR(("tty_unregister_driver error=%d\n", rc));
3728 		put_tty_driver(serial_driver);
3729 	}
3730 
3731 	/* reset devices */
3732 	info = slgt_device_list;
3733 	while(info) {
3734 		reset_port(info);
3735 		info = info->next_device;
3736 	}
3737 
3738 	/* release devices */
3739 	info = slgt_device_list;
3740 	while(info) {
3741 #if SYNCLINK_GENERIC_HDLC
3742 		hdlcdev_exit(info);
3743 #endif
3744 		free_dma_bufs(info);
3745 		free_tmp_rbuf(info);
3746 		if (info->port_num == 0)
3747 			release_resources(info);
3748 		tmp = info;
3749 		info = info->next_device;
3750 		tty_port_destroy(&tmp->port);
3751 		kfree(tmp);
3752 	}
3753 
3754 	if (pci_registered)
3755 		pci_unregister_driver(&pci_driver);
3756 }
3757 
3758 /*
3759  *  Driver initialization entry point.
3760  */
3761 static int __init slgt_init(void)
3762 {
3763 	int rc;
3764 
3765 	printk(KERN_INFO "%s\n", driver_name);
3766 
3767 	serial_driver = alloc_tty_driver(MAX_DEVICES);
3768 	if (!serial_driver) {
3769 		printk("%s can't allocate tty driver\n", driver_name);
3770 		return -ENOMEM;
3771 	}
3772 
3773 	/* Initialize the tty_driver structure */
3774 
3775 	serial_driver->driver_name = slgt_driver_name;
3776 	serial_driver->name = tty_dev_prefix;
3777 	serial_driver->major = ttymajor;
3778 	serial_driver->minor_start = 64;
3779 	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
3780 	serial_driver->subtype = SERIAL_TYPE_NORMAL;
3781 	serial_driver->init_termios = tty_std_termios;
3782 	serial_driver->init_termios.c_cflag =
3783 		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
3784 	serial_driver->init_termios.c_ispeed = 9600;
3785 	serial_driver->init_termios.c_ospeed = 9600;
3786 	serial_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
3787 	tty_set_operations(serial_driver, &ops);
3788 	if ((rc = tty_register_driver(serial_driver)) < 0) {
3789 		DBGERR(("%s can't register serial driver\n", driver_name));
3790 		put_tty_driver(serial_driver);
3791 		serial_driver = NULL;
3792 		goto error;
3793 	}
3794 
3795 	printk(KERN_INFO "%s, tty major#%d\n",
3796 	       driver_name, serial_driver->major);
3797 
3798 	slgt_device_count = 0;
3799 	if ((rc = pci_register_driver(&pci_driver)) < 0) {
3800 		printk("%s pci_register_driver error=%d\n", driver_name, rc);
3801 		goto error;
3802 	}
3803 	pci_registered = true;
3804 
3805 	if (!slgt_device_list)
3806 		printk("%s no devices found\n",driver_name);
3807 
3808 	return 0;
3809 
3810 error:
3811 	slgt_cleanup();
3812 	return rc;
3813 }
3814 
3815 static void __exit slgt_exit(void)
3816 {
3817 	slgt_cleanup();
3818 }
3819 
3820 module_init(slgt_init);
3821 module_exit(slgt_exit);
3822 
3823 /*
3824  * register access routines
3825  */
3826 
3827 #define CALC_REGADDR() \
3828 	unsigned long reg_addr = ((unsigned long)info->reg_addr) + addr; \
3829 	if (addr >= 0x80) \
3830 		reg_addr += (info->port_num) * 32; \
3831 	else if (addr >= 0x40)	\
3832 		reg_addr += (info->port_num) * 16;
3833 
3834 static __u8 rd_reg8(struct slgt_info *info, unsigned int addr)
3835 {
3836 	CALC_REGADDR();
3837 	return readb((void __iomem *)reg_addr);
3838 }
3839 
3840 static void wr_reg8(struct slgt_info *info, unsigned int addr, __u8 value)
3841 {
3842 	CALC_REGADDR();
3843 	writeb(value, (void __iomem *)reg_addr);
3844 }
3845 
3846 static __u16 rd_reg16(struct slgt_info *info, unsigned int addr)
3847 {
3848 	CALC_REGADDR();
3849 	return readw((void __iomem *)reg_addr);
3850 }
3851 
3852 static void wr_reg16(struct slgt_info *info, unsigned int addr, __u16 value)
3853 {
3854 	CALC_REGADDR();
3855 	writew(value, (void __iomem *)reg_addr);
3856 }
3857 
3858 static __u32 rd_reg32(struct slgt_info *info, unsigned int addr)
3859 {
3860 	CALC_REGADDR();
3861 	return readl((void __iomem *)reg_addr);
3862 }
3863 
3864 static void wr_reg32(struct slgt_info *info, unsigned int addr, __u32 value)
3865 {
3866 	CALC_REGADDR();
3867 	writel(value, (void __iomem *)reg_addr);
3868 }
3869 
3870 static void rdma_reset(struct slgt_info *info)
3871 {
3872 	unsigned int i;
3873 
3874 	/* set reset bit */
3875 	wr_reg32(info, RDCSR, BIT1);
3876 
3877 	/* wait for enable bit cleared */
3878 	for(i=0 ; i < 1000 ; i++)
3879 		if (!(rd_reg32(info, RDCSR) & BIT0))
3880 			break;
3881 }
3882 
3883 static void tdma_reset(struct slgt_info *info)
3884 {
3885 	unsigned int i;
3886 
3887 	/* set reset bit */
3888 	wr_reg32(info, TDCSR, BIT1);
3889 
3890 	/* wait for enable bit cleared */
3891 	for(i=0 ; i < 1000 ; i++)
3892 		if (!(rd_reg32(info, TDCSR) & BIT0))
3893 			break;
3894 }
3895 
3896 /*
3897  * enable internal loopback
3898  * TxCLK and RxCLK are generated from BRG
3899  * and TxD is looped back to RxD internally.
3900  */
3901 static void enable_loopback(struct slgt_info *info)
3902 {
3903 	/* SCR (serial control) BIT2=loopback enable */
3904 	wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT2));
3905 
3906 	if (info->params.mode != MGSL_MODE_ASYNC) {
3907 		/* CCR (clock control)
3908 		 * 07..05  tx clock source (010 = BRG)
3909 		 * 04..02  rx clock source (010 = BRG)
3910 		 * 01      auxclk enable   (0 = disable)
3911 		 * 00      BRG enable      (1 = enable)
3912 		 *
3913 		 * 0100 1001
3914 		 */
3915 		wr_reg8(info, CCR, 0x49);
3916 
3917 		/* set speed if available, otherwise use default */
3918 		if (info->params.clock_speed)
3919 			set_rate(info, info->params.clock_speed);
3920 		else
3921 			set_rate(info, 3686400);
3922 	}
3923 }
3924 
3925 /*
3926  *  set baud rate generator to specified rate
3927  */
3928 static void set_rate(struct slgt_info *info, u32 rate)
3929 {
3930 	unsigned int div;
3931 	unsigned int osc = info->base_clock;
3932 
3933 	/* div = osc/rate - 1
3934 	 *
3935 	 * Round div up if osc/rate is not integer to
3936 	 * force to next slowest rate.
3937 	 */
3938 
3939 	if (rate) {
3940 		div = osc/rate;
3941 		if (!(osc % rate) && div)
3942 			div--;
3943 		wr_reg16(info, BDR, (unsigned short)div);
3944 	}
3945 }
3946 
3947 static void rx_stop(struct slgt_info *info)
3948 {
3949 	unsigned short val;
3950 
3951 	/* disable and reset receiver */
3952 	val = rd_reg16(info, RCR) & ~BIT1;          /* clear enable bit */
3953 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3954 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3955 
3956 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA + IRQ_RXIDLE);
3957 
3958 	/* clear pending rx interrupts */
3959 	wr_reg16(info, SSR, IRQ_RXIDLE + IRQ_RXOVER);
3960 
3961 	rdma_reset(info);
3962 
3963 	info->rx_enabled = false;
3964 	info->rx_restart = false;
3965 }
3966 
3967 static void rx_start(struct slgt_info *info)
3968 {
3969 	unsigned short val;
3970 
3971 	slgt_irq_off(info, IRQ_RXOVER + IRQ_RXDATA);
3972 
3973 	/* clear pending rx overrun IRQ */
3974 	wr_reg16(info, SSR, IRQ_RXOVER);
3975 
3976 	/* reset and disable receiver */
3977 	val = rd_reg16(info, RCR) & ~BIT1; /* clear enable bit */
3978 	wr_reg16(info, RCR, (unsigned short)(val | BIT2)); /* set reset bit */
3979 	wr_reg16(info, RCR, val);                  /* clear reset bit */
3980 
3981 	rdma_reset(info);
3982 	reset_rbufs(info);
3983 
3984 	if (info->rx_pio) {
3985 		/* rx request when rx FIFO not empty */
3986 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) & ~BIT14));
3987 		slgt_irq_on(info, IRQ_RXDATA);
3988 		if (info->params.mode == MGSL_MODE_ASYNC) {
3989 			/* enable saving of rx status */
3990 			wr_reg32(info, RDCSR, BIT6);
3991 		}
3992 	} else {
3993 		/* rx request when rx FIFO half full */
3994 		wr_reg16(info, SCR, (unsigned short)(rd_reg16(info, SCR) | BIT14));
3995 		/* set 1st descriptor address */
3996 		wr_reg32(info, RDDAR, info->rbufs[0].pdesc);
3997 
3998 		if (info->params.mode != MGSL_MODE_ASYNC) {
3999 			/* enable rx DMA and DMA interrupt */
4000 			wr_reg32(info, RDCSR, (BIT2 + BIT0));
4001 		} else {
4002 			/* enable saving of rx status, rx DMA and DMA interrupt */
4003 			wr_reg32(info, RDCSR, (BIT6 + BIT2 + BIT0));
4004 		}
4005 	}
4006 
4007 	slgt_irq_on(info, IRQ_RXOVER);
4008 
4009 	/* enable receiver */
4010 	wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | BIT1));
4011 
4012 	info->rx_restart = false;
4013 	info->rx_enabled = true;
4014 }
4015 
4016 static void tx_start(struct slgt_info *info)
4017 {
4018 	if (!info->tx_enabled) {
4019 		wr_reg16(info, TCR,
4020 			 (unsigned short)((rd_reg16(info, TCR) | BIT1) & ~BIT2));
4021 		info->tx_enabled = true;
4022 	}
4023 
4024 	if (desc_count(info->tbufs[info->tbuf_start])) {
4025 		info->drop_rts_on_tx_done = false;
4026 
4027 		if (info->params.mode != MGSL_MODE_ASYNC) {
4028 			if (info->params.flags & HDLC_FLAG_AUTO_RTS) {
4029 				get_signals(info);
4030 				if (!(info->signals & SerialSignal_RTS)) {
4031 					info->signals |= SerialSignal_RTS;
4032 					set_signals(info);
4033 					info->drop_rts_on_tx_done = true;
4034 				}
4035 			}
4036 
4037 			slgt_irq_off(info, IRQ_TXDATA);
4038 			slgt_irq_on(info, IRQ_TXUNDER + IRQ_TXIDLE);
4039 			/* clear tx idle and underrun status bits */
4040 			wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4041 		} else {
4042 			slgt_irq_off(info, IRQ_TXDATA);
4043 			slgt_irq_on(info, IRQ_TXIDLE);
4044 			/* clear tx idle status bit */
4045 			wr_reg16(info, SSR, IRQ_TXIDLE);
4046 		}
4047 		/* set 1st descriptor address and start DMA */
4048 		wr_reg32(info, TDDAR, info->tbufs[info->tbuf_start].pdesc);
4049 		wr_reg32(info, TDCSR, BIT2 + BIT0);
4050 		info->tx_active = true;
4051 	}
4052 }
4053 
4054 static void tx_stop(struct slgt_info *info)
4055 {
4056 	unsigned short val;
4057 
4058 	del_timer(&info->tx_timer);
4059 
4060 	tdma_reset(info);
4061 
4062 	/* reset and disable transmitter */
4063 	val = rd_reg16(info, TCR) & ~BIT1;          /* clear enable bit */
4064 	wr_reg16(info, TCR, (unsigned short)(val | BIT2)); /* set reset bit */
4065 
4066 	slgt_irq_off(info, IRQ_TXDATA + IRQ_TXIDLE + IRQ_TXUNDER);
4067 
4068 	/* clear tx idle and underrun status bit */
4069 	wr_reg16(info, SSR, (unsigned short)(IRQ_TXIDLE + IRQ_TXUNDER));
4070 
4071 	reset_tbufs(info);
4072 
4073 	info->tx_enabled = false;
4074 	info->tx_active = false;
4075 }
4076 
4077 static void reset_port(struct slgt_info *info)
4078 {
4079 	if (!info->reg_addr)
4080 		return;
4081 
4082 	tx_stop(info);
4083 	rx_stop(info);
4084 
4085 	info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
4086 	set_signals(info);
4087 
4088 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4089 }
4090 
4091 static void reset_adapter(struct slgt_info *info)
4092 {
4093 	int i;
4094 	for (i=0; i < info->port_count; ++i) {
4095 		if (info->port_array[i])
4096 			reset_port(info->port_array[i]);
4097 	}
4098 }
4099 
4100 static void async_mode(struct slgt_info *info)
4101 {
4102   	unsigned short val;
4103 
4104 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4105 	tx_stop(info);
4106 	rx_stop(info);
4107 
4108 	/* TCR (tx control)
4109 	 *
4110 	 * 15..13  mode, 010=async
4111 	 * 12..10  encoding, 000=NRZ
4112 	 * 09      parity enable
4113 	 * 08      1=odd parity, 0=even parity
4114 	 * 07      1=RTS driver control
4115 	 * 06      1=break enable
4116 	 * 05..04  character length
4117 	 *         00=5 bits
4118 	 *         01=6 bits
4119 	 *         10=7 bits
4120 	 *         11=8 bits
4121 	 * 03      0=1 stop bit, 1=2 stop bits
4122 	 * 02      reset
4123 	 * 01      enable
4124 	 * 00      auto-CTS enable
4125 	 */
4126 	val = 0x4000;
4127 
4128 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4129 		val |= BIT7;
4130 
4131 	if (info->params.parity != ASYNC_PARITY_NONE) {
4132 		val |= BIT9;
4133 		if (info->params.parity == ASYNC_PARITY_ODD)
4134 			val |= BIT8;
4135 	}
4136 
4137 	switch (info->params.data_bits)
4138 	{
4139 	case 6: val |= BIT4; break;
4140 	case 7: val |= BIT5; break;
4141 	case 8: val |= BIT5 + BIT4; break;
4142 	}
4143 
4144 	if (info->params.stop_bits != 1)
4145 		val |= BIT3;
4146 
4147 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4148 		val |= BIT0;
4149 
4150 	wr_reg16(info, TCR, val);
4151 
4152 	/* RCR (rx control)
4153 	 *
4154 	 * 15..13  mode, 010=async
4155 	 * 12..10  encoding, 000=NRZ
4156 	 * 09      parity enable
4157 	 * 08      1=odd parity, 0=even parity
4158 	 * 07..06  reserved, must be 0
4159 	 * 05..04  character length
4160 	 *         00=5 bits
4161 	 *         01=6 bits
4162 	 *         10=7 bits
4163 	 *         11=8 bits
4164 	 * 03      reserved, must be zero
4165 	 * 02      reset
4166 	 * 01      enable
4167 	 * 00      auto-DCD enable
4168 	 */
4169 	val = 0x4000;
4170 
4171 	if (info->params.parity != ASYNC_PARITY_NONE) {
4172 		val |= BIT9;
4173 		if (info->params.parity == ASYNC_PARITY_ODD)
4174 			val |= BIT8;
4175 	}
4176 
4177 	switch (info->params.data_bits)
4178 	{
4179 	case 6: val |= BIT4; break;
4180 	case 7: val |= BIT5; break;
4181 	case 8: val |= BIT5 + BIT4; break;
4182 	}
4183 
4184 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4185 		val |= BIT0;
4186 
4187 	wr_reg16(info, RCR, val);
4188 
4189 	/* CCR (clock control)
4190 	 *
4191 	 * 07..05  011 = tx clock source is BRG/16
4192 	 * 04..02  010 = rx clock source is BRG
4193 	 * 01      0 = auxclk disabled
4194 	 * 00      1 = BRG enabled
4195 	 *
4196 	 * 0110 1001
4197 	 */
4198 	wr_reg8(info, CCR, 0x69);
4199 
4200 	msc_set_vcr(info);
4201 
4202 	/* SCR (serial control)
4203 	 *
4204 	 * 15  1=tx req on FIFO half empty
4205 	 * 14  1=rx req on FIFO half full
4206 	 * 13  tx data  IRQ enable
4207 	 * 12  tx idle  IRQ enable
4208 	 * 11  rx break on IRQ enable
4209 	 * 10  rx data  IRQ enable
4210 	 * 09  rx break off IRQ enable
4211 	 * 08  overrun  IRQ enable
4212 	 * 07  DSR      IRQ enable
4213 	 * 06  CTS      IRQ enable
4214 	 * 05  DCD      IRQ enable
4215 	 * 04  RI       IRQ enable
4216 	 * 03  0=16x sampling, 1=8x sampling
4217 	 * 02  1=txd->rxd internal loopback enable
4218 	 * 01  reserved, must be zero
4219 	 * 00  1=master IRQ enable
4220 	 */
4221 	val = BIT15 + BIT14 + BIT0;
4222 	/* JCR[8] : 1 = x8 async mode feature available */
4223 	if ((rd_reg32(info, JCR) & BIT8) && info->params.data_rate &&
4224 	    ((info->base_clock < (info->params.data_rate * 16)) ||
4225 	     (info->base_clock % (info->params.data_rate * 16)))) {
4226 		/* use 8x sampling */
4227 		val |= BIT3;
4228 		set_rate(info, info->params.data_rate * 8);
4229 	} else {
4230 		/* use 16x sampling */
4231 		set_rate(info, info->params.data_rate * 16);
4232 	}
4233 	wr_reg16(info, SCR, val);
4234 
4235 	slgt_irq_on(info, IRQ_RXBREAK | IRQ_RXOVER);
4236 
4237 	if (info->params.loopback)
4238 		enable_loopback(info);
4239 }
4240 
4241 static void sync_mode(struct slgt_info *info)
4242 {
4243 	unsigned short val;
4244 
4245 	slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
4246 	tx_stop(info);
4247 	rx_stop(info);
4248 
4249 	/* TCR (tx control)
4250 	 *
4251 	 * 15..13  mode
4252 	 *         000=HDLC/SDLC
4253 	 *         001=raw bit synchronous
4254 	 *         010=asynchronous/isochronous
4255 	 *         011=monosync byte synchronous
4256 	 *         100=bisync byte synchronous
4257 	 *         101=xsync byte synchronous
4258 	 * 12..10  encoding
4259 	 * 09      CRC enable
4260 	 * 08      CRC32
4261 	 * 07      1=RTS driver control
4262 	 * 06      preamble enable
4263 	 * 05..04  preamble length
4264 	 * 03      share open/close flag
4265 	 * 02      reset
4266 	 * 01      enable
4267 	 * 00      auto-CTS enable
4268 	 */
4269 	val = BIT2;
4270 
4271 	switch(info->params.mode) {
4272 	case MGSL_MODE_XSYNC:
4273 		val |= BIT15 + BIT13;
4274 		break;
4275 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4276 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4277 	case MGSL_MODE_RAW:      val |= BIT13; break;
4278 	}
4279 	if (info->if_mode & MGSL_INTERFACE_RTS_EN)
4280 		val |= BIT7;
4281 
4282 	switch(info->params.encoding)
4283 	{
4284 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4285 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4286 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4287 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4288 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4289 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4290 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4291 	}
4292 
4293 	switch (info->params.crc_type & HDLC_CRC_MASK)
4294 	{
4295 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4296 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4297 	}
4298 
4299 	if (info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE)
4300 		val |= BIT6;
4301 
4302 	switch (info->params.preamble_length)
4303 	{
4304 	case HDLC_PREAMBLE_LENGTH_16BITS: val |= BIT5; break;
4305 	case HDLC_PREAMBLE_LENGTH_32BITS: val |= BIT4; break;
4306 	case HDLC_PREAMBLE_LENGTH_64BITS: val |= BIT5 + BIT4; break;
4307 	}
4308 
4309 	if (info->params.flags & HDLC_FLAG_AUTO_CTS)
4310 		val |= BIT0;
4311 
4312 	wr_reg16(info, TCR, val);
4313 
4314 	/* TPR (transmit preamble) */
4315 
4316 	switch (info->params.preamble)
4317 	{
4318 	case HDLC_PREAMBLE_PATTERN_FLAGS: val = 0x7e; break;
4319 	case HDLC_PREAMBLE_PATTERN_ONES:  val = 0xff; break;
4320 	case HDLC_PREAMBLE_PATTERN_ZEROS: val = 0x00; break;
4321 	case HDLC_PREAMBLE_PATTERN_10:    val = 0x55; break;
4322 	case HDLC_PREAMBLE_PATTERN_01:    val = 0xaa; break;
4323 	default:                          val = 0x7e; break;
4324 	}
4325 	wr_reg8(info, TPR, (unsigned char)val);
4326 
4327 	/* RCR (rx control)
4328 	 *
4329 	 * 15..13  mode
4330 	 *         000=HDLC/SDLC
4331 	 *         001=raw bit synchronous
4332 	 *         010=asynchronous/isochronous
4333 	 *         011=monosync byte synchronous
4334 	 *         100=bisync byte synchronous
4335 	 *         101=xsync byte synchronous
4336 	 * 12..10  encoding
4337 	 * 09      CRC enable
4338 	 * 08      CRC32
4339 	 * 07..03  reserved, must be 0
4340 	 * 02      reset
4341 	 * 01      enable
4342 	 * 00      auto-DCD enable
4343 	 */
4344 	val = 0;
4345 
4346 	switch(info->params.mode) {
4347 	case MGSL_MODE_XSYNC:
4348 		val |= BIT15 + BIT13;
4349 		break;
4350 	case MGSL_MODE_MONOSYNC: val |= BIT14 + BIT13; break;
4351 	case MGSL_MODE_BISYNC:   val |= BIT15; break;
4352 	case MGSL_MODE_RAW:      val |= BIT13; break;
4353 	}
4354 
4355 	switch(info->params.encoding)
4356 	{
4357 	case HDLC_ENCODING_NRZB:          val |= BIT10; break;
4358 	case HDLC_ENCODING_NRZI_MARK:     val |= BIT11; break;
4359 	case HDLC_ENCODING_NRZI:          val |= BIT11 + BIT10; break;
4360 	case HDLC_ENCODING_BIPHASE_MARK:  val |= BIT12; break;
4361 	case HDLC_ENCODING_BIPHASE_SPACE: val |= BIT12 + BIT10; break;
4362 	case HDLC_ENCODING_BIPHASE_LEVEL: val |= BIT12 + BIT11; break;
4363 	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: val |= BIT12 + BIT11 + BIT10; break;
4364 	}
4365 
4366 	switch (info->params.crc_type & HDLC_CRC_MASK)
4367 	{
4368 	case HDLC_CRC_16_CCITT: val |= BIT9; break;
4369 	case HDLC_CRC_32_CCITT: val |= BIT9 + BIT8; break;
4370 	}
4371 
4372 	if (info->params.flags & HDLC_FLAG_AUTO_DCD)
4373 		val |= BIT0;
4374 
4375 	wr_reg16(info, RCR, val);
4376 
4377 	/* CCR (clock control)
4378 	 *
4379 	 * 07..05  tx clock source
4380 	 * 04..02  rx clock source
4381 	 * 01      auxclk enable
4382 	 * 00      BRG enable
4383 	 */
4384 	val = 0;
4385 
4386 	if (info->params.flags & HDLC_FLAG_TXC_BRG)
4387 	{
4388 		// when RxC source is DPLL, BRG generates 16X DPLL
4389 		// reference clock, so take TxC from BRG/16 to get
4390 		// transmit clock at actual data rate
4391 		if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4392 			val |= BIT6 + BIT5;	/* 011, txclk = BRG/16 */
4393 		else
4394 			val |= BIT6;	/* 010, txclk = BRG */
4395 	}
4396 	else if (info->params.flags & HDLC_FLAG_TXC_DPLL)
4397 		val |= BIT7;	/* 100, txclk = DPLL Input */
4398 	else if (info->params.flags & HDLC_FLAG_TXC_RXCPIN)
4399 		val |= BIT5;	/* 001, txclk = RXC Input */
4400 
4401 	if (info->params.flags & HDLC_FLAG_RXC_BRG)
4402 		val |= BIT3;	/* 010, rxclk = BRG */
4403 	else if (info->params.flags & HDLC_FLAG_RXC_DPLL)
4404 		val |= BIT4;	/* 100, rxclk = DPLL */
4405 	else if (info->params.flags & HDLC_FLAG_RXC_TXCPIN)
4406 		val |= BIT2;	/* 001, rxclk = TXC Input */
4407 
4408 	if (info->params.clock_speed)
4409 		val |= BIT1 + BIT0;
4410 
4411 	wr_reg8(info, CCR, (unsigned char)val);
4412 
4413 	if (info->params.flags & (HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL))
4414 	{
4415 		// program DPLL mode
4416 		switch(info->params.encoding)
4417 		{
4418 		case HDLC_ENCODING_BIPHASE_MARK:
4419 		case HDLC_ENCODING_BIPHASE_SPACE:
4420 			val = BIT7; break;
4421 		case HDLC_ENCODING_BIPHASE_LEVEL:
4422 		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:
4423 			val = BIT7 + BIT6; break;
4424 		default: val = BIT6;	// NRZ encodings
4425 		}
4426 		wr_reg16(info, RCR, (unsigned short)(rd_reg16(info, RCR) | val));
4427 
4428 		// DPLL requires a 16X reference clock from BRG
4429 		set_rate(info, info->params.clock_speed * 16);
4430 	}
4431 	else
4432 		set_rate(info, info->params.clock_speed);
4433 
4434 	tx_set_idle(info);
4435 
4436 	msc_set_vcr(info);
4437 
4438 	/* SCR (serial control)
4439 	 *
4440 	 * 15  1=tx req on FIFO half empty
4441 	 * 14  1=rx req on FIFO half full
4442 	 * 13  tx data  IRQ enable
4443 	 * 12  tx idle  IRQ enable
4444 	 * 11  underrun IRQ enable
4445 	 * 10  rx data  IRQ enable
4446 	 * 09  rx idle  IRQ enable
4447 	 * 08  overrun  IRQ enable
4448 	 * 07  DSR      IRQ enable
4449 	 * 06  CTS      IRQ enable
4450 	 * 05  DCD      IRQ enable
4451 	 * 04  RI       IRQ enable
4452 	 * 03  reserved, must be zero
4453 	 * 02  1=txd->rxd internal loopback enable
4454 	 * 01  reserved, must be zero
4455 	 * 00  1=master IRQ enable
4456 	 */
4457 	wr_reg16(info, SCR, BIT15 + BIT14 + BIT0);
4458 
4459 	if (info->params.loopback)
4460 		enable_loopback(info);
4461 }
4462 
4463 /*
4464  *  set transmit idle mode
4465  */
4466 static void tx_set_idle(struct slgt_info *info)
4467 {
4468 	unsigned char val;
4469 	unsigned short tcr;
4470 
4471 	/* if preamble enabled (tcr[6] == 1) then tx idle size = 8 bits
4472 	 * else tcr[5:4] = tx idle size: 00 = 8 bits, 01 = 16 bits
4473 	 */
4474 	tcr = rd_reg16(info, TCR);
4475 	if (info->idle_mode & HDLC_TXIDLE_CUSTOM_16) {
4476 		/* disable preamble, set idle size to 16 bits */
4477 		tcr = (tcr & ~(BIT6 + BIT5)) | BIT4;
4478 		/* MSB of 16 bit idle specified in tx preamble register (TPR) */
4479 		wr_reg8(info, TPR, (unsigned char)((info->idle_mode >> 8) & 0xff));
4480 	} else if (!(tcr & BIT6)) {
4481 		/* preamble is disabled, set idle size to 8 bits */
4482 		tcr &= ~(BIT5 + BIT4);
4483 	}
4484 	wr_reg16(info, TCR, tcr);
4485 
4486 	if (info->idle_mode & (HDLC_TXIDLE_CUSTOM_8 | HDLC_TXIDLE_CUSTOM_16)) {
4487 		/* LSB of custom tx idle specified in tx idle register */
4488 		val = (unsigned char)(info->idle_mode & 0xff);
4489 	} else {
4490 		/* standard 8 bit idle patterns */
4491 		switch(info->idle_mode)
4492 		{
4493 		case HDLC_TXIDLE_FLAGS:          val = 0x7e; break;
4494 		case HDLC_TXIDLE_ALT_ZEROS_ONES:
4495 		case HDLC_TXIDLE_ALT_MARK_SPACE: val = 0xaa; break;
4496 		case HDLC_TXIDLE_ZEROS:
4497 		case HDLC_TXIDLE_SPACE:          val = 0x00; break;
4498 		default:                         val = 0xff;
4499 		}
4500 	}
4501 
4502 	wr_reg8(info, TIR, val);
4503 }
4504 
4505 /*
4506  * get state of V24 status (input) signals
4507  */
4508 static void get_signals(struct slgt_info *info)
4509 {
4510 	unsigned short status = rd_reg16(info, SSR);
4511 
4512 	/* clear all serial signals except RTS and DTR */
4513 	info->signals &= SerialSignal_RTS | SerialSignal_DTR;
4514 
4515 	if (status & BIT3)
4516 		info->signals |= SerialSignal_DSR;
4517 	if (status & BIT2)
4518 		info->signals |= SerialSignal_CTS;
4519 	if (status & BIT1)
4520 		info->signals |= SerialSignal_DCD;
4521 	if (status & BIT0)
4522 		info->signals |= SerialSignal_RI;
4523 }
4524 
4525 /*
4526  * set V.24 Control Register based on current configuration
4527  */
4528 static void msc_set_vcr(struct slgt_info *info)
4529 {
4530 	unsigned char val = 0;
4531 
4532 	/* VCR (V.24 control)
4533 	 *
4534 	 * 07..04  serial IF select
4535 	 * 03      DTR
4536 	 * 02      RTS
4537 	 * 01      LL
4538 	 * 00      RL
4539 	 */
4540 
4541 	switch(info->if_mode & MGSL_INTERFACE_MASK)
4542 	{
4543 	case MGSL_INTERFACE_RS232:
4544 		val |= BIT5; /* 0010 */
4545 		break;
4546 	case MGSL_INTERFACE_V35:
4547 		val |= BIT7 + BIT6 + BIT5; /* 1110 */
4548 		break;
4549 	case MGSL_INTERFACE_RS422:
4550 		val |= BIT6; /* 0100 */
4551 		break;
4552 	}
4553 
4554 	if (info->if_mode & MGSL_INTERFACE_MSB_FIRST)
4555 		val |= BIT4;
4556 	if (info->signals & SerialSignal_DTR)
4557 		val |= BIT3;
4558 	if (info->signals & SerialSignal_RTS)
4559 		val |= BIT2;
4560 	if (info->if_mode & MGSL_INTERFACE_LL)
4561 		val |= BIT1;
4562 	if (info->if_mode & MGSL_INTERFACE_RL)
4563 		val |= BIT0;
4564 	wr_reg8(info, VCR, val);
4565 }
4566 
4567 /*
4568  * set state of V24 control (output) signals
4569  */
4570 static void set_signals(struct slgt_info *info)
4571 {
4572 	unsigned char val = rd_reg8(info, VCR);
4573 	if (info->signals & SerialSignal_DTR)
4574 		val |= BIT3;
4575 	else
4576 		val &= ~BIT3;
4577 	if (info->signals & SerialSignal_RTS)
4578 		val |= BIT2;
4579 	else
4580 		val &= ~BIT2;
4581 	wr_reg8(info, VCR, val);
4582 }
4583 
4584 /*
4585  * free range of receive DMA buffers (i to last)
4586  */
4587 static void free_rbufs(struct slgt_info *info, unsigned int i, unsigned int last)
4588 {
4589 	int done = 0;
4590 
4591 	while(!done) {
4592 		/* reset current buffer for reuse */
4593 		info->rbufs[i].status = 0;
4594 		set_desc_count(info->rbufs[i], info->rbuf_fill_level);
4595 		if (i == last)
4596 			done = 1;
4597 		if (++i == info->rbuf_count)
4598 			i = 0;
4599 	}
4600 	info->rbuf_current = i;
4601 }
4602 
4603 /*
4604  * mark all receive DMA buffers as free
4605  */
4606 static void reset_rbufs(struct slgt_info *info)
4607 {
4608 	free_rbufs(info, 0, info->rbuf_count - 1);
4609 	info->rbuf_fill_index = 0;
4610 	info->rbuf_fill_count = 0;
4611 }
4612 
4613 /*
4614  * pass receive HDLC frame to upper layer
4615  *
4616  * return true if frame available, otherwise false
4617  */
4618 static bool rx_get_frame(struct slgt_info *info)
4619 {
4620 	unsigned int start, end;
4621 	unsigned short status;
4622 	unsigned int framesize = 0;
4623 	unsigned long flags;
4624 	struct tty_struct *tty = info->port.tty;
4625 	unsigned char addr_field = 0xff;
4626 	unsigned int crc_size = 0;
4627 
4628 	switch (info->params.crc_type & HDLC_CRC_MASK) {
4629 	case HDLC_CRC_16_CCITT: crc_size = 2; break;
4630 	case HDLC_CRC_32_CCITT: crc_size = 4; break;
4631 	}
4632 
4633 check_again:
4634 
4635 	framesize = 0;
4636 	addr_field = 0xff;
4637 	start = end = info->rbuf_current;
4638 
4639 	for (;;) {
4640 		if (!desc_complete(info->rbufs[end]))
4641 			goto cleanup;
4642 
4643 		if (framesize == 0 && info->params.addr_filter != 0xff)
4644 			addr_field = info->rbufs[end].buf[0];
4645 
4646 		framesize += desc_count(info->rbufs[end]);
4647 
4648 		if (desc_eof(info->rbufs[end]))
4649 			break;
4650 
4651 		if (++end == info->rbuf_count)
4652 			end = 0;
4653 
4654 		if (end == info->rbuf_current) {
4655 			if (info->rx_enabled){
4656 				spin_lock_irqsave(&info->lock,flags);
4657 				rx_start(info);
4658 				spin_unlock_irqrestore(&info->lock,flags);
4659 			}
4660 			goto cleanup;
4661 		}
4662 	}
4663 
4664 	/* status
4665 	 *
4666 	 * 15      buffer complete
4667 	 * 14..06  reserved
4668 	 * 05..04  residue
4669 	 * 02      eof (end of frame)
4670 	 * 01      CRC error
4671 	 * 00      abort
4672 	 */
4673 	status = desc_status(info->rbufs[end]);
4674 
4675 	/* ignore CRC bit if not using CRC (bit is undefined) */
4676 	if ((info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_NONE)
4677 		status &= ~BIT1;
4678 
4679 	if (framesize == 0 ||
4680 		 (addr_field != 0xff && addr_field != info->params.addr_filter)) {
4681 		free_rbufs(info, start, end);
4682 		goto check_again;
4683 	}
4684 
4685 	if (framesize < (2 + crc_size) || status & BIT0) {
4686 		info->icount.rxshort++;
4687 		framesize = 0;
4688 	} else if (status & BIT1) {
4689 		info->icount.rxcrc++;
4690 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX))
4691 			framesize = 0;
4692 	}
4693 
4694 #if SYNCLINK_GENERIC_HDLC
4695 	if (framesize == 0) {
4696 		info->netdev->stats.rx_errors++;
4697 		info->netdev->stats.rx_frame_errors++;
4698 	}
4699 #endif
4700 
4701 	DBGBH(("%s rx frame status=%04X size=%d\n",
4702 		info->device_name, status, framesize));
4703 	DBGDATA(info, info->rbufs[start].buf, min_t(int, framesize, info->rbuf_fill_level), "rx");
4704 
4705 	if (framesize) {
4706 		if (!(info->params.crc_type & HDLC_CRC_RETURN_EX)) {
4707 			framesize -= crc_size;
4708 			crc_size = 0;
4709 		}
4710 
4711 		if (framesize > info->max_frame_size + crc_size)
4712 			info->icount.rxlong++;
4713 		else {
4714 			/* copy dma buffer(s) to contiguous temp buffer */
4715 			int copy_count = framesize;
4716 			int i = start;
4717 			unsigned char *p = info->tmp_rbuf;
4718 			info->tmp_rbuf_count = framesize;
4719 
4720 			info->icount.rxok++;
4721 
4722 			while(copy_count) {
4723 				int partial_count = min_t(int, copy_count, info->rbuf_fill_level);
4724 				memcpy(p, info->rbufs[i].buf, partial_count);
4725 				p += partial_count;
4726 				copy_count -= partial_count;
4727 				if (++i == info->rbuf_count)
4728 					i = 0;
4729 			}
4730 
4731 			if (info->params.crc_type & HDLC_CRC_RETURN_EX) {
4732 				*p = (status & BIT1) ? RX_CRC_ERROR : RX_OK;
4733 				framesize++;
4734 			}
4735 
4736 #if SYNCLINK_GENERIC_HDLC
4737 			if (info->netcount)
4738 				hdlcdev_rx(info,info->tmp_rbuf, framesize);
4739 			else
4740 #endif
4741 				ldisc_receive_buf(tty, info->tmp_rbuf, info->flag_buf, framesize);
4742 		}
4743 	}
4744 	free_rbufs(info, start, end);
4745 	return true;
4746 
4747 cleanup:
4748 	return false;
4749 }
4750 
4751 /*
4752  * pass receive buffer (RAW synchronous mode) to tty layer
4753  * return true if buffer available, otherwise false
4754  */
4755 static bool rx_get_buf(struct slgt_info *info)
4756 {
4757 	unsigned int i = info->rbuf_current;
4758 	unsigned int count;
4759 
4760 	if (!desc_complete(info->rbufs[i]))
4761 		return false;
4762 	count = desc_count(info->rbufs[i]);
4763 	switch(info->params.mode) {
4764 	case MGSL_MODE_MONOSYNC:
4765 	case MGSL_MODE_BISYNC:
4766 	case MGSL_MODE_XSYNC:
4767 		/* ignore residue in byte synchronous modes */
4768 		if (desc_residue(info->rbufs[i]))
4769 			count--;
4770 		break;
4771 	}
4772 	DBGDATA(info, info->rbufs[i].buf, count, "rx");
4773 	DBGINFO(("rx_get_buf size=%d\n", count));
4774 	if (count)
4775 		ldisc_receive_buf(info->port.tty, info->rbufs[i].buf,
4776 				  info->flag_buf, count);
4777 	free_rbufs(info, i, i);
4778 	return true;
4779 }
4780 
4781 static void reset_tbufs(struct slgt_info *info)
4782 {
4783 	unsigned int i;
4784 	info->tbuf_current = 0;
4785 	for (i=0 ; i < info->tbuf_count ; i++) {
4786 		info->tbufs[i].status = 0;
4787 		info->tbufs[i].count  = 0;
4788 	}
4789 }
4790 
4791 /*
4792  * return number of free transmit DMA buffers
4793  */
4794 static unsigned int free_tbuf_count(struct slgt_info *info)
4795 {
4796 	unsigned int count = 0;
4797 	unsigned int i = info->tbuf_current;
4798 
4799 	do
4800 	{
4801 		if (desc_count(info->tbufs[i]))
4802 			break; /* buffer in use */
4803 		++count;
4804 		if (++i == info->tbuf_count)
4805 			i=0;
4806 	} while (i != info->tbuf_current);
4807 
4808 	/* if tx DMA active, last zero count buffer is in use */
4809 	if (count && (rd_reg32(info, TDCSR) & BIT0))
4810 		--count;
4811 
4812 	return count;
4813 }
4814 
4815 /*
4816  * return number of bytes in unsent transmit DMA buffers
4817  * and the serial controller tx FIFO
4818  */
4819 static unsigned int tbuf_bytes(struct slgt_info *info)
4820 {
4821 	unsigned int total_count = 0;
4822 	unsigned int i = info->tbuf_current;
4823 	unsigned int reg_value;
4824 	unsigned int count;
4825 	unsigned int active_buf_count = 0;
4826 
4827 	/*
4828 	 * Add descriptor counts for all tx DMA buffers.
4829 	 * If count is zero (cleared by DMA controller after read),
4830 	 * the buffer is complete or is actively being read from.
4831 	 *
4832 	 * Record buf_count of last buffer with zero count starting
4833 	 * from current ring position. buf_count is mirror
4834 	 * copy of count and is not cleared by serial controller.
4835 	 * If DMA controller is active, that buffer is actively
4836 	 * being read so add to total.
4837 	 */
4838 	do {
4839 		count = desc_count(info->tbufs[i]);
4840 		if (count)
4841 			total_count += count;
4842 		else if (!total_count)
4843 			active_buf_count = info->tbufs[i].buf_count;
4844 		if (++i == info->tbuf_count)
4845 			i = 0;
4846 	} while (i != info->tbuf_current);
4847 
4848 	/* read tx DMA status register */
4849 	reg_value = rd_reg32(info, TDCSR);
4850 
4851 	/* if tx DMA active, last zero count buffer is in use */
4852 	if (reg_value & BIT0)
4853 		total_count += active_buf_count;
4854 
4855 	/* add tx FIFO count = reg_value[15..8] */
4856 	total_count += (reg_value >> 8) & 0xff;
4857 
4858 	/* if transmitter active add one byte for shift register */
4859 	if (info->tx_active)
4860 		total_count++;
4861 
4862 	return total_count;
4863 }
4864 
4865 /*
4866  * load data into transmit DMA buffer ring and start transmitter if needed
4867  * return true if data accepted, otherwise false (buffers full)
4868  */
4869 static bool tx_load(struct slgt_info *info, const char *buf, unsigned int size)
4870 {
4871 	unsigned short count;
4872 	unsigned int i;
4873 	struct slgt_desc *d;
4874 
4875 	/* check required buffer space */
4876 	if (DIV_ROUND_UP(size, DMABUFSIZE) > free_tbuf_count(info))
4877 		return false;
4878 
4879 	DBGDATA(info, buf, size, "tx");
4880 
4881 	/*
4882 	 * copy data to one or more DMA buffers in circular ring
4883 	 * tbuf_start   = first buffer for this data
4884 	 * tbuf_current = next free buffer
4885 	 *
4886 	 * Copy all data before making data visible to DMA controller by
4887 	 * setting descriptor count of the first buffer.
4888 	 * This prevents an active DMA controller from reading the first DMA
4889 	 * buffers of a frame and stopping before the final buffers are filled.
4890 	 */
4891 
4892 	info->tbuf_start = i = info->tbuf_current;
4893 
4894 	while (size) {
4895 		d = &info->tbufs[i];
4896 
4897 		count = (unsigned short)((size > DMABUFSIZE) ? DMABUFSIZE : size);
4898 		memcpy(d->buf, buf, count);
4899 
4900 		size -= count;
4901 		buf  += count;
4902 
4903 		/*
4904 		 * set EOF bit for last buffer of HDLC frame or
4905 		 * for every buffer in raw mode
4906 		 */
4907 		if ((!size && info->params.mode == MGSL_MODE_HDLC) ||
4908 		    info->params.mode == MGSL_MODE_RAW)
4909 			set_desc_eof(*d, 1);
4910 		else
4911 			set_desc_eof(*d, 0);
4912 
4913 		/* set descriptor count for all but first buffer */
4914 		if (i != info->tbuf_start)
4915 			set_desc_count(*d, count);
4916 		d->buf_count = count;
4917 
4918 		if (++i == info->tbuf_count)
4919 			i = 0;
4920 	}
4921 
4922 	info->tbuf_current = i;
4923 
4924 	/* set first buffer count to make new data visible to DMA controller */
4925 	d = &info->tbufs[info->tbuf_start];
4926 	set_desc_count(*d, d->buf_count);
4927 
4928 	/* start transmitter if needed and update transmit timeout */
4929 	if (!info->tx_active)
4930 		tx_start(info);
4931 	update_tx_timer(info);
4932 
4933 	return true;
4934 }
4935 
4936 static int register_test(struct slgt_info *info)
4937 {
4938 	static unsigned short patterns[] =
4939 		{0x0000, 0xffff, 0xaaaa, 0x5555, 0x6969, 0x9696};
4940 	static unsigned int count = ARRAY_SIZE(patterns);
4941 	unsigned int i;
4942 	int rc = 0;
4943 
4944 	for (i=0 ; i < count ; i++) {
4945 		wr_reg16(info, TIR, patterns[i]);
4946 		wr_reg16(info, BDR, patterns[(i+1)%count]);
4947 		if ((rd_reg16(info, TIR) != patterns[i]) ||
4948 		    (rd_reg16(info, BDR) != patterns[(i+1)%count])) {
4949 			rc = -ENODEV;
4950 			break;
4951 		}
4952 	}
4953 	info->gpio_present = (rd_reg32(info, JCR) & BIT5) ? 1 : 0;
4954 	info->init_error = rc ? 0 : DiagStatus_AddressFailure;
4955 	return rc;
4956 }
4957 
4958 static int irq_test(struct slgt_info *info)
4959 {
4960 	unsigned long timeout;
4961 	unsigned long flags;
4962 	struct tty_struct *oldtty = info->port.tty;
4963 	u32 speed = info->params.data_rate;
4964 
4965 	info->params.data_rate = 921600;
4966 	info->port.tty = NULL;
4967 
4968 	spin_lock_irqsave(&info->lock, flags);
4969 	async_mode(info);
4970 	slgt_irq_on(info, IRQ_TXIDLE);
4971 
4972 	/* enable transmitter */
4973 	wr_reg16(info, TCR,
4974 		(unsigned short)(rd_reg16(info, TCR) | BIT1));
4975 
4976 	/* write one byte and wait for tx idle */
4977 	wr_reg16(info, TDR, 0);
4978 
4979 	/* assume failure */
4980 	info->init_error = DiagStatus_IrqFailure;
4981 	info->irq_occurred = false;
4982 
4983 	spin_unlock_irqrestore(&info->lock, flags);
4984 
4985 	timeout=100;
4986 	while(timeout-- && !info->irq_occurred)
4987 		msleep_interruptible(10);
4988 
4989 	spin_lock_irqsave(&info->lock,flags);
4990 	reset_port(info);
4991 	spin_unlock_irqrestore(&info->lock,flags);
4992 
4993 	info->params.data_rate = speed;
4994 	info->port.tty = oldtty;
4995 
4996 	info->init_error = info->irq_occurred ? 0 : DiagStatus_IrqFailure;
4997 	return info->irq_occurred ? 0 : -ENODEV;
4998 }
4999 
5000 static int loopback_test_rx(struct slgt_info *info)
5001 {
5002 	unsigned char *src, *dest;
5003 	int count;
5004 
5005 	if (desc_complete(info->rbufs[0])) {
5006 		count = desc_count(info->rbufs[0]);
5007 		src   = info->rbufs[0].buf;
5008 		dest  = info->tmp_rbuf;
5009 
5010 		for( ; count ; count-=2, src+=2) {
5011 			/* src=data byte (src+1)=status byte */
5012 			if (!(*(src+1) & (BIT9 + BIT8))) {
5013 				*dest = *src;
5014 				dest++;
5015 				info->tmp_rbuf_count++;
5016 			}
5017 		}
5018 		DBGDATA(info, info->tmp_rbuf, info->tmp_rbuf_count, "rx");
5019 		return 1;
5020 	}
5021 	return 0;
5022 }
5023 
5024 static int loopback_test(struct slgt_info *info)
5025 {
5026 #define TESTFRAMESIZE 20
5027 
5028 	unsigned long timeout;
5029 	u16 count = TESTFRAMESIZE;
5030 	unsigned char buf[TESTFRAMESIZE];
5031 	int rc = -ENODEV;
5032 	unsigned long flags;
5033 
5034 	struct tty_struct *oldtty = info->port.tty;
5035 	MGSL_PARAMS params;
5036 
5037 	memcpy(&params, &info->params, sizeof(params));
5038 
5039 	info->params.mode = MGSL_MODE_ASYNC;
5040 	info->params.data_rate = 921600;
5041 	info->params.loopback = 1;
5042 	info->port.tty = NULL;
5043 
5044 	/* build and send transmit frame */
5045 	for (count = 0; count < TESTFRAMESIZE; ++count)
5046 		buf[count] = (unsigned char)count;
5047 
5048 	info->tmp_rbuf_count = 0;
5049 	memset(info->tmp_rbuf, 0, TESTFRAMESIZE);
5050 
5051 	/* program hardware for HDLC and enabled receiver */
5052 	spin_lock_irqsave(&info->lock,flags);
5053 	async_mode(info);
5054 	rx_start(info);
5055 	tx_load(info, buf, count);
5056 	spin_unlock_irqrestore(&info->lock, flags);
5057 
5058 	/* wait for receive complete */
5059 	for (timeout = 100; timeout; --timeout) {
5060 		msleep_interruptible(10);
5061 		if (loopback_test_rx(info)) {
5062 			rc = 0;
5063 			break;
5064 		}
5065 	}
5066 
5067 	/* verify received frame length and contents */
5068 	if (!rc && (info->tmp_rbuf_count != count ||
5069 		  memcmp(buf, info->tmp_rbuf, count))) {
5070 		rc = -ENODEV;
5071 	}
5072 
5073 	spin_lock_irqsave(&info->lock,flags);
5074 	reset_adapter(info);
5075 	spin_unlock_irqrestore(&info->lock,flags);
5076 
5077 	memcpy(&info->params, &params, sizeof(info->params));
5078 	info->port.tty = oldtty;
5079 
5080 	info->init_error = rc ? DiagStatus_DmaFailure : 0;
5081 	return rc;
5082 }
5083 
5084 static int adapter_test(struct slgt_info *info)
5085 {
5086 	DBGINFO(("testing %s\n", info->device_name));
5087 	if (register_test(info) < 0) {
5088 		printk("register test failure %s addr=%08X\n",
5089 			info->device_name, info->phys_reg_addr);
5090 	} else if (irq_test(info) < 0) {
5091 		printk("IRQ test failure %s IRQ=%d\n",
5092 			info->device_name, info->irq_level);
5093 	} else if (loopback_test(info) < 0) {
5094 		printk("loopback test failure %s\n", info->device_name);
5095 	}
5096 	return info->init_error;
5097 }
5098 
5099 /*
5100  * transmit timeout handler
5101  */
5102 static void tx_timeout(struct timer_list *t)
5103 {
5104 	struct slgt_info *info = from_timer(info, t, tx_timer);
5105 	unsigned long flags;
5106 
5107 	DBGINFO(("%s tx_timeout\n", info->device_name));
5108 	if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
5109 		info->icount.txtimeout++;
5110 	}
5111 	spin_lock_irqsave(&info->lock,flags);
5112 	tx_stop(info);
5113 	spin_unlock_irqrestore(&info->lock,flags);
5114 
5115 #if SYNCLINK_GENERIC_HDLC
5116 	if (info->netcount)
5117 		hdlcdev_tx_done(info);
5118 	else
5119 #endif
5120 		bh_transmit(info);
5121 }
5122 
5123 /*
5124  * receive buffer polling timer
5125  */
5126 static void rx_timeout(struct timer_list *t)
5127 {
5128 	struct slgt_info *info = from_timer(info, t, rx_timer);
5129 	unsigned long flags;
5130 
5131 	DBGINFO(("%s rx_timeout\n", info->device_name));
5132 	spin_lock_irqsave(&info->lock, flags);
5133 	info->pending_bh |= BH_RECEIVE;
5134 	spin_unlock_irqrestore(&info->lock, flags);
5135 	bh_handler(&info->task);
5136 }
5137 
5138