Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* r3964 linediscipline for linux |
2 | * | |
3 | * ----------------------------------------------------------- | |
4 | * Copyright by | |
5 | * Philips Automation Projects | |
6 | * Kassel (Germany) | |
1da177e4 LT |
7 | * ----------------------------------------------------------- |
8 | * This software may be used and distributed according to the terms of | |
9 | * the GNU General Public License, incorporated herein by reference. | |
10 | * | |
11 | * Author: | |
12 | * L. Haag | |
13 | * | |
14 | * $Log: n_r3964.c,v $ | |
15 | * Revision 1.10 2001/03/18 13:02:24 dwmw2 | |
16 | * Fix timer usage, use spinlocks properly. | |
17 | * | |
18 | * Revision 1.9 2001/03/18 12:52:14 dwmw2 | |
19 | * Merge changes in 2.4.2 | |
20 | * | |
21 | * Revision 1.8 2000/03/23 14:14:54 dwmw2 | |
22 | * Fix race in sleeping in r3964_read() | |
23 | * | |
24 | * Revision 1.7 1999/28/08 11:41:50 dwmw2 | |
25 | * Port to 2.3 kernel | |
26 | * | |
27 | * Revision 1.6 1998/09/30 00:40:40 dwmw2 | |
28 | * Fixed compilation on 2.0.x kernels | |
29 | * Updated to newly registered tty-ldisc number 9 | |
30 | * | |
31 | * Revision 1.5 1998/09/04 21:57:36 dwmw2 | |
32 | * Signal handling bug fixes, port to 2.1.x. | |
33 | * | |
34 | * Revision 1.4 1998/04/02 20:26:59 lhaag | |
35 | * select, blocking, ... | |
36 | * | |
37 | * Revision 1.3 1998/02/12 18:58:43 root | |
38 | * fixed some memory leaks | |
39 | * calculation of checksum characters | |
40 | * | |
41 | * Revision 1.2 1998/02/07 13:03:34 root | |
42 | * ioctl read_telegram | |
43 | * | |
44 | * Revision 1.1 1998/02/06 19:21:03 root | |
45 | * Initial revision | |
46 | * | |
47 | * | |
48 | */ | |
49 | ||
50 | #include <linux/module.h> | |
51 | #include <linux/kernel.h> | |
52 | #include <linux/sched.h> | |
53 | #include <linux/types.h> | |
54 | #include <linux/fcntl.h> | |
55 | #include <linux/interrupt.h> | |
56 | #include <linux/ptrace.h> | |
57 | #include <linux/ioport.h> | |
58 | #include <linux/in.h> | |
59 | #include <linux/slab.h> | |
405f5571 | 60 | #include <linux/smp_lock.h> |
1da177e4 LT |
61 | #include <linux/tty.h> |
62 | #include <linux/errno.h> | |
5e07e1cc JS |
63 | #include <linux/string.h> /* used in new tty drivers */ |
64 | #include <linux/signal.h> /* used in new tty drivers */ | |
1da177e4 LT |
65 | #include <linux/ioctl.h> |
66 | #include <linux/n_r3964.h> | |
67 | #include <linux/poll.h> | |
68 | #include <linux/init.h> | |
69 | #include <asm/uaccess.h> | |
70 | ||
5e07e1cc | 71 | /*#define DEBUG_QUEUE*/ |
1da177e4 LT |
72 | |
73 | /* Log successful handshake and protocol operations */ | |
5e07e1cc | 74 | /*#define DEBUG_PROTO_S*/ |
1da177e4 LT |
75 | |
76 | /* Log handshake and protocol errors: */ | |
5e07e1cc | 77 | /*#define DEBUG_PROTO_E*/ |
1da177e4 LT |
78 | |
79 | /* Log Linediscipline operations (open, close, read, write...): */ | |
5e07e1cc | 80 | /*#define DEBUG_LDISC*/ |
1da177e4 LT |
81 | |
82 | /* Log module and memory operations (init, cleanup; kmalloc, kfree): */ | |
5e07e1cc | 83 | /*#define DEBUG_MODUL*/ |
1da177e4 LT |
84 | |
85 | /* Macro helpers for debug output: */ | |
5e07e1cc | 86 | #define TRACE(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 LT |
87 | |
88 | #ifdef DEBUG_MODUL | |
5e07e1cc | 89 | #define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 90 | #else |
5e07e1cc | 91 | #define TRACE_M(fmt, arg...) do {} while (0) |
1da177e4 | 92 | #endif |
1da177e4 | 93 | #ifdef DEBUG_PROTO_S |
5e07e1cc | 94 | #define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 95 | #else |
5e07e1cc | 96 | #define TRACE_PS(fmt, arg...) do {} while (0) |
1da177e4 | 97 | #endif |
1da177e4 | 98 | #ifdef DEBUG_PROTO_E |
5e07e1cc | 99 | #define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 100 | #else |
5e07e1cc | 101 | #define TRACE_PE(fmt, arg...) do {} while (0) |
1da177e4 | 102 | #endif |
1da177e4 | 103 | #ifdef DEBUG_LDISC |
5e07e1cc | 104 | #define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 105 | #else |
5e07e1cc | 106 | #define TRACE_L(fmt, arg...) do {} while (0) |
1da177e4 | 107 | #endif |
1da177e4 | 108 | #ifdef DEBUG_QUEUE |
5e07e1cc | 109 | #define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 110 | #else |
5e07e1cc | 111 | #define TRACE_Q(fmt, arg...) do {} while (0) |
1da177e4 | 112 | #endif |
1da177e4 LT |
113 | static void add_tx_queue(struct r3964_info *, struct r3964_block_header *); |
114 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code); | |
115 | static void put_char(struct r3964_info *pInfo, unsigned char ch); | |
116 | static void trigger_transmit(struct r3964_info *pInfo); | |
117 | static void retry_transmit(struct r3964_info *pInfo); | |
118 | static void transmit_block(struct r3964_info *pInfo); | |
119 | static void receive_char(struct r3964_info *pInfo, const unsigned char c); | |
120 | static void receive_error(struct r3964_info *pInfo, const char flag); | |
121 | static void on_timeout(unsigned long priv); | |
3cec556a | 122 | static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg); |
5e07e1cc JS |
123 | static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
124 | unsigned char __user * buf); | |
1da177e4 | 125 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
5e07e1cc JS |
126 | int error_code, struct r3964_block_header *pBlock); |
127 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, | |
128 | struct r3964_client_info *pClient); | |
129 | static void remove_client_block(struct r3964_info *pInfo, | |
130 | struct r3964_client_info *pClient); | |
1da177e4 | 131 | |
5e07e1cc | 132 | static int r3964_open(struct tty_struct *tty); |
1da177e4 LT |
133 | static void r3964_close(struct tty_struct *tty); |
134 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, | |
5e07e1cc JS |
135 | unsigned char __user * buf, size_t nr); |
136 | static ssize_t r3964_write(struct tty_struct *tty, struct file *file, | |
137 | const unsigned char *buf, size_t nr); | |
138 | static int r3964_ioctl(struct tty_struct *tty, struct file *file, | |
139 | unsigned int cmd, unsigned long arg); | |
140 | static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old); | |
141 | static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, | |
142 | struct poll_table_struct *wait); | |
1da177e4 | 143 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
5e07e1cc | 144 | char *fp, int count); |
1da177e4 | 145 | |
a352def2 | 146 | static struct tty_ldisc_ops tty_ldisc_N_R3964 = { |
5e07e1cc JS |
147 | .owner = THIS_MODULE, |
148 | .magic = TTY_LDISC_MAGIC, | |
149 | .name = "R3964", | |
150 | .open = r3964_open, | |
151 | .close = r3964_close, | |
152 | .read = r3964_read, | |
153 | .write = r3964_write, | |
154 | .ioctl = r3964_ioctl, | |
1da177e4 | 155 | .set_termios = r3964_set_termios, |
5e07e1cc | 156 | .poll = r3964_poll, |
1da177e4 | 157 | .receive_buf = r3964_receive_buf, |
1da177e4 LT |
158 | }; |
159 | ||
1da177e4 LT |
160 | static void dump_block(const unsigned char *block, unsigned int length) |
161 | { | |
5e07e1cc JS |
162 | unsigned int i, j; |
163 | char linebuf[16 * 3 + 1]; | |
164 | ||
165 | for (i = 0; i < length; i += 16) { | |
166 | for (j = 0; (j < 16) && (j + i < length); j++) { | |
167 | sprintf(linebuf + 3 * j, "%02x ", block[i + j]); | |
168 | } | |
169 | linebuf[3 * j] = '\0'; | |
170 | TRACE_PS("%s", linebuf); | |
171 | } | |
1da177e4 LT |
172 | } |
173 | ||
1da177e4 LT |
174 | /************************************************************* |
175 | * Driver initialisation | |
176 | *************************************************************/ | |
177 | ||
1da177e4 LT |
178 | /************************************************************* |
179 | * Module support routines | |
180 | *************************************************************/ | |
181 | ||
182 | static void __exit r3964_exit(void) | |
183 | { | |
5e07e1cc JS |
184 | int status; |
185 | ||
186 | TRACE_M("cleanup_module()"); | |
187 | ||
188 | status = tty_unregister_ldisc(N_R3964); | |
189 | ||
190 | if (status != 0) { | |
191 | printk(KERN_ERR "r3964: error unregistering linediscipline: " | |
192 | "%d\n", status); | |
193 | } else { | |
194 | TRACE_L("linediscipline successfully unregistered"); | |
195 | } | |
1da177e4 LT |
196 | } |
197 | ||
198 | static int __init r3964_init(void) | |
199 | { | |
5e07e1cc JS |
200 | int status; |
201 | ||
202 | printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n"); | |
203 | ||
204 | /* | |
205 | * Register the tty line discipline | |
206 | */ | |
207 | ||
208 | status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964); | |
209 | if (status == 0) { | |
210 | TRACE_L("line discipline %d registered", N_R3964); | |
211 | TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags, | |
212 | tty_ldisc_N_R3964.num); | |
213 | TRACE_L("open=%p", tty_ldisc_N_R3964.open); | |
214 | TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964); | |
215 | } else { | |
216 | printk(KERN_ERR "r3964: error registering line discipline: " | |
217 | "%d\n", status); | |
218 | } | |
219 | return status; | |
1da177e4 LT |
220 | } |
221 | ||
222 | module_init(r3964_init); | |
223 | module_exit(r3964_exit); | |
224 | ||
1da177e4 LT |
225 | /************************************************************* |
226 | * Protocol implementation routines | |
227 | *************************************************************/ | |
228 | ||
5e07e1cc JS |
229 | static void add_tx_queue(struct r3964_info *pInfo, |
230 | struct r3964_block_header *pHeader) | |
1da177e4 | 231 | { |
5e07e1cc JS |
232 | unsigned long flags; |
233 | ||
234 | spin_lock_irqsave(&pInfo->lock, flags); | |
235 | ||
236 | pHeader->next = NULL; | |
237 | ||
238 | if (pInfo->tx_last == NULL) { | |
239 | pInfo->tx_first = pInfo->tx_last = pHeader; | |
240 | } else { | |
241 | pInfo->tx_last->next = pHeader; | |
242 | pInfo->tx_last = pHeader; | |
243 | } | |
244 | ||
245 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
246 | ||
247 | TRACE_Q("add_tx_queue %p, length %d, tx_first = %p", | |
248 | pHeader, pHeader->length, pInfo->tx_first); | |
1da177e4 LT |
249 | } |
250 | ||
251 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code) | |
252 | { | |
5e07e1cc JS |
253 | struct r3964_block_header *pHeader; |
254 | unsigned long flags; | |
1da177e4 | 255 | #ifdef DEBUG_QUEUE |
5e07e1cc | 256 | struct r3964_block_header *pDump; |
1da177e4 | 257 | #endif |
1da177e4 | 258 | |
5e07e1cc JS |
259 | pHeader = pInfo->tx_first; |
260 | ||
261 | if (pHeader == NULL) | |
262 | return; | |
1da177e4 LT |
263 | |
264 | #ifdef DEBUG_QUEUE | |
5e07e1cc JS |
265 | printk("r3964: remove_from_tx_queue: %p, length %u - ", |
266 | pHeader, pHeader->length); | |
267 | for (pDump = pHeader; pDump; pDump = pDump->next) | |
268 | printk("%p ", pDump); | |
269 | printk("\n"); | |
1da177e4 LT |
270 | #endif |
271 | ||
5e07e1cc JS |
272 | if (pHeader->owner) { |
273 | if (error_code) { | |
274 | add_msg(pHeader->owner, R3964_MSG_ACK, 0, | |
275 | error_code, NULL); | |
276 | } else { | |
277 | add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length, | |
278 | error_code, NULL); | |
279 | } | |
280 | wake_up_interruptible(&pInfo->read_wait); | |
281 | } | |
282 | ||
283 | spin_lock_irqsave(&pInfo->lock, flags); | |
284 | ||
285 | pInfo->tx_first = pHeader->next; | |
286 | if (pInfo->tx_first == NULL) { | |
287 | pInfo->tx_last = NULL; | |
288 | } | |
289 | ||
290 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
291 | ||
292 | kfree(pHeader); | |
293 | TRACE_M("remove_from_tx_queue - kfree %p", pHeader); | |
1da177e4 | 294 | |
5e07e1cc JS |
295 | TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p", |
296 | pInfo->tx_first, pInfo->tx_last); | |
1da177e4 LT |
297 | } |
298 | ||
5e07e1cc JS |
299 | static void add_rx_queue(struct r3964_info *pInfo, |
300 | struct r3964_block_header *pHeader) | |
1da177e4 | 301 | { |
5e07e1cc JS |
302 | unsigned long flags; |
303 | ||
304 | spin_lock_irqsave(&pInfo->lock, flags); | |
305 | ||
306 | pHeader->next = NULL; | |
307 | ||
308 | if (pInfo->rx_last == NULL) { | |
309 | pInfo->rx_first = pInfo->rx_last = pHeader; | |
310 | } else { | |
311 | pInfo->rx_last->next = pHeader; | |
312 | pInfo->rx_last = pHeader; | |
313 | } | |
314 | pInfo->blocks_in_rx_queue++; | |
315 | ||
316 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
317 | ||
318 | TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d", | |
319 | pHeader, pHeader->length, | |
320 | pInfo->rx_first, pInfo->blocks_in_rx_queue); | |
1da177e4 LT |
321 | } |
322 | ||
323 | static void remove_from_rx_queue(struct r3964_info *pInfo, | |
5e07e1cc | 324 | struct r3964_block_header *pHeader) |
1da177e4 | 325 | { |
5e07e1cc JS |
326 | unsigned long flags; |
327 | struct r3964_block_header *pFind; | |
328 | ||
329 | if (pHeader == NULL) | |
330 | return; | |
331 | ||
332 | TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", | |
333 | pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); | |
334 | TRACE_Q("remove_from_rx_queue: %p, length %u", | |
335 | pHeader, pHeader->length); | |
336 | ||
337 | spin_lock_irqsave(&pInfo->lock, flags); | |
338 | ||
339 | if (pInfo->rx_first == pHeader) { | |
340 | /* Remove the first block in the linked list: */ | |
341 | pInfo->rx_first = pHeader->next; | |
342 | ||
343 | if (pInfo->rx_first == NULL) { | |
344 | pInfo->rx_last = NULL; | |
345 | } | |
346 | pInfo->blocks_in_rx_queue--; | |
347 | } else { | |
348 | /* Find block to remove: */ | |
349 | for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) { | |
350 | if (pFind->next == pHeader) { | |
351 | /* Got it. */ | |
352 | pFind->next = pHeader->next; | |
353 | pInfo->blocks_in_rx_queue--; | |
354 | if (pFind->next == NULL) { | |
355 | /* Oh, removed the last one! */ | |
356 | pInfo->rx_last = pFind; | |
357 | } | |
358 | break; | |
359 | } | |
360 | } | |
361 | } | |
362 | ||
363 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
364 | ||
365 | kfree(pHeader); | |
366 | TRACE_M("remove_from_rx_queue - kfree %p", pHeader); | |
367 | ||
368 | TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", | |
369 | pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); | |
1da177e4 LT |
370 | } |
371 | ||
372 | static void put_char(struct r3964_info *pInfo, unsigned char ch) | |
373 | { | |
5e07e1cc | 374 | struct tty_struct *tty = pInfo->tty; |
f34d7a5b | 375 | /* FIXME: put_char should not be called from an IRQ */ |
51383f69 | 376 | tty_put_char(tty, ch); |
5e07e1cc | 377 | pInfo->bcc ^= ch; |
1da177e4 LT |
378 | } |
379 | ||
380 | static void flush(struct r3964_info *pInfo) | |
381 | { | |
5e07e1cc | 382 | struct tty_struct *tty = pInfo->tty; |
1da177e4 | 383 | |
f34d7a5b | 384 | if (tty == NULL || tty->ops->flush_chars == NULL) |
5e07e1cc | 385 | return; |
f34d7a5b | 386 | tty->ops->flush_chars(tty); |
1da177e4 LT |
387 | } |
388 | ||
389 | static void trigger_transmit(struct r3964_info *pInfo) | |
390 | { | |
5e07e1cc | 391 | unsigned long flags; |
1da177e4 | 392 | |
5e07e1cc | 393 | spin_lock_irqsave(&pInfo->lock, flags); |
1da177e4 | 394 | |
5e07e1cc JS |
395 | if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) { |
396 | pInfo->state = R3964_TX_REQUEST; | |
397 | pInfo->nRetry = 0; | |
398 | pInfo->flags &= ~R3964_ERROR; | |
399 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
1da177e4 | 400 | |
5e07e1cc | 401 | spin_unlock_irqrestore(&pInfo->lock, flags); |
1da177e4 | 402 | |
5e07e1cc | 403 | TRACE_PS("trigger_transmit - sent STX"); |
1da177e4 | 404 | |
5e07e1cc JS |
405 | put_char(pInfo, STX); |
406 | flush(pInfo); | |
1da177e4 | 407 | |
5e07e1cc JS |
408 | pInfo->bcc = 0; |
409 | } else { | |
410 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
411 | } | |
1da177e4 LT |
412 | } |
413 | ||
414 | static void retry_transmit(struct r3964_info *pInfo) | |
415 | { | |
5e07e1cc JS |
416 | if (pInfo->nRetry < R3964_MAX_RETRIES) { |
417 | TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry); | |
418 | pInfo->bcc = 0; | |
419 | put_char(pInfo, STX); | |
420 | flush(pInfo); | |
421 | pInfo->state = R3964_TX_REQUEST; | |
422 | pInfo->nRetry++; | |
423 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
424 | } else { | |
425 | TRACE_PE("transmission failed after %d retries", | |
426 | R3964_MAX_RETRIES); | |
427 | ||
428 | remove_from_tx_queue(pInfo, R3964_TX_FAIL); | |
429 | ||
430 | put_char(pInfo, NAK); | |
431 | flush(pInfo); | |
432 | pInfo->state = R3964_IDLE; | |
433 | ||
434 | trigger_transmit(pInfo); | |
435 | } | |
1da177e4 LT |
436 | } |
437 | ||
1da177e4 LT |
438 | static void transmit_block(struct r3964_info *pInfo) |
439 | { | |
5e07e1cc JS |
440 | struct tty_struct *tty = pInfo->tty; |
441 | struct r3964_block_header *pBlock = pInfo->tx_first; | |
442 | int room = 0; | |
443 | ||
f34d7a5b | 444 | if (tty == NULL || pBlock == NULL) { |
5e07e1cc JS |
445 | return; |
446 | } | |
447 | ||
f34d7a5b | 448 | room = tty_write_room(tty); |
5e07e1cc JS |
449 | |
450 | TRACE_PS("transmit_block %p, room %d, length %d", | |
451 | pBlock, room, pBlock->length); | |
452 | ||
453 | while (pInfo->tx_position < pBlock->length) { | |
454 | if (room < 2) | |
455 | break; | |
456 | ||
457 | if (pBlock->data[pInfo->tx_position] == DLE) { | |
458 | /* send additional DLE char: */ | |
459 | put_char(pInfo, DLE); | |
460 | } | |
461 | put_char(pInfo, pBlock->data[pInfo->tx_position++]); | |
462 | ||
463 | room--; | |
464 | } | |
465 | ||
466 | if ((pInfo->tx_position == pBlock->length) && (room >= 3)) { | |
467 | put_char(pInfo, DLE); | |
468 | put_char(pInfo, ETX); | |
469 | if (pInfo->flags & R3964_BCC) { | |
470 | put_char(pInfo, pInfo->bcc); | |
471 | } | |
472 | pInfo->state = R3964_WAIT_FOR_TX_ACK; | |
473 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
474 | } | |
475 | flush(pInfo); | |
1da177e4 LT |
476 | } |
477 | ||
478 | static void on_receive_block(struct r3964_info *pInfo) | |
479 | { | |
5e07e1cc JS |
480 | unsigned int length; |
481 | struct r3964_client_info *pClient; | |
482 | struct r3964_block_header *pBlock; | |
483 | ||
484 | length = pInfo->rx_position; | |
485 | ||
486 | /* compare byte checksum characters: */ | |
487 | if (pInfo->flags & R3964_BCC) { | |
488 | if (pInfo->bcc != pInfo->last_rx) { | |
489 | TRACE_PE("checksum error - got %x but expected %x", | |
490 | pInfo->last_rx, pInfo->bcc); | |
491 | pInfo->flags |= R3964_CHECKSUM; | |
492 | } | |
493 | } | |
494 | ||
495 | /* check for errors (parity, overrun,...): */ | |
496 | if (pInfo->flags & R3964_ERROR) { | |
497 | TRACE_PE("on_receive_block - transmission failed error %x", | |
498 | pInfo->flags & R3964_ERROR); | |
499 | ||
500 | put_char(pInfo, NAK); | |
501 | flush(pInfo); | |
502 | if (pInfo->nRetry < R3964_MAX_RETRIES) { | |
503 | pInfo->state = R3964_WAIT_FOR_RX_REPEAT; | |
504 | pInfo->nRetry++; | |
505 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC); | |
506 | } else { | |
507 | TRACE_PE("on_receive_block - failed after max retries"); | |
508 | pInfo->state = R3964_IDLE; | |
509 | } | |
510 | return; | |
511 | } | |
512 | ||
513 | /* received block; submit DLE: */ | |
514 | put_char(pInfo, DLE); | |
515 | flush(pInfo); | |
516 | del_timer_sync(&pInfo->tmr); | |
517 | TRACE_PS(" rx success: got %d chars", length); | |
518 | ||
519 | /* prepare struct r3964_block_header: */ | |
520 | pBlock = kmalloc(length + sizeof(struct r3964_block_header), | |
521 | GFP_KERNEL); | |
522 | TRACE_M("on_receive_block - kmalloc %p", pBlock); | |
523 | ||
524 | if (pBlock == NULL) | |
525 | return; | |
526 | ||
527 | pBlock->length = length; | |
528 | pBlock->data = ((unsigned char *)pBlock) + | |
529 | sizeof(struct r3964_block_header); | |
530 | pBlock->locks = 0; | |
531 | pBlock->next = NULL; | |
532 | pBlock->owner = NULL; | |
533 | ||
534 | memcpy(pBlock->data, pInfo->rx_buf, length); | |
535 | ||
536 | /* queue block into rx_queue: */ | |
537 | add_rx_queue(pInfo, pBlock); | |
538 | ||
539 | /* notify attached client processes: */ | |
540 | for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { | |
541 | if (pClient->sig_flags & R3964_SIG_DATA) { | |
542 | add_msg(pClient, R3964_MSG_DATA, length, R3964_OK, | |
543 | pBlock); | |
544 | } | |
545 | } | |
546 | wake_up_interruptible(&pInfo->read_wait); | |
1da177e4 | 547 | |
5e07e1cc JS |
548 | pInfo->state = R3964_IDLE; |
549 | ||
550 | trigger_transmit(pInfo); | |
551 | } | |
1da177e4 LT |
552 | |
553 | static void receive_char(struct r3964_info *pInfo, const unsigned char c) | |
554 | { | |
5e07e1cc JS |
555 | switch (pInfo->state) { |
556 | case R3964_TX_REQUEST: | |
557 | if (c == DLE) { | |
558 | TRACE_PS("TX_REQUEST - got DLE"); | |
559 | ||
560 | pInfo->state = R3964_TRANSMITTING; | |
561 | pInfo->tx_position = 0; | |
562 | ||
563 | transmit_block(pInfo); | |
564 | } else if (c == STX) { | |
565 | if (pInfo->nRetry == 0) { | |
566 | TRACE_PE("TX_REQUEST - init conflict"); | |
567 | if (pInfo->priority == R3964_SLAVE) { | |
568 | goto start_receiving; | |
569 | } | |
570 | } else { | |
571 | TRACE_PE("TX_REQUEST - secondary init " | |
572 | "conflict!? Switching to SLAVE mode " | |
573 | "for next rx."); | |
574 | goto start_receiving; | |
575 | } | |
576 | } else { | |
577 | TRACE_PE("TX_REQUEST - char != DLE: %x", c); | |
578 | retry_transmit(pInfo); | |
579 | } | |
580 | break; | |
581 | case R3964_TRANSMITTING: | |
582 | if (c == NAK) { | |
583 | TRACE_PE("TRANSMITTING - got NAK"); | |
584 | retry_transmit(pInfo); | |
585 | } else { | |
586 | TRACE_PE("TRANSMITTING - got invalid char"); | |
587 | ||
588 | pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY; | |
589 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
590 | } | |
591 | break; | |
592 | case R3964_WAIT_FOR_TX_ACK: | |
593 | if (c == DLE) { | |
594 | TRACE_PS("WAIT_FOR_TX_ACK - got DLE"); | |
595 | remove_from_tx_queue(pInfo, R3964_OK); | |
596 | ||
597 | pInfo->state = R3964_IDLE; | |
598 | trigger_transmit(pInfo); | |
599 | } else { | |
600 | retry_transmit(pInfo); | |
601 | } | |
602 | break; | |
603 | case R3964_WAIT_FOR_RX_REPEAT: | |
af901ca1 | 604 | /* FALLTHROUGH */ |
5e07e1cc JS |
605 | case R3964_IDLE: |
606 | if (c == STX) { | |
607 | /* Prevent rx_queue from overflow: */ | |
608 | if (pInfo->blocks_in_rx_queue >= | |
609 | R3964_MAX_BLOCKS_IN_RX_QUEUE) { | |
610 | TRACE_PE("IDLE - got STX but no space in " | |
611 | "rx_queue!"); | |
612 | pInfo->state = R3964_WAIT_FOR_RX_BUF; | |
613 | mod_timer(&pInfo->tmr, | |
614 | jiffies + R3964_TO_NO_BUF); | |
615 | break; | |
616 | } | |
1da177e4 | 617 | start_receiving: |
5e07e1cc JS |
618 | /* Ok, start receiving: */ |
619 | TRACE_PS("IDLE - got STX"); | |
620 | pInfo->rx_position = 0; | |
621 | pInfo->last_rx = 0; | |
622 | pInfo->flags &= ~R3964_ERROR; | |
623 | pInfo->state = R3964_RECEIVING; | |
624 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
625 | pInfo->nRetry = 0; | |
626 | put_char(pInfo, DLE); | |
627 | flush(pInfo); | |
628 | pInfo->bcc = 0; | |
629 | } | |
630 | break; | |
631 | case R3964_RECEIVING: | |
632 | if (pInfo->rx_position < RX_BUF_SIZE) { | |
633 | pInfo->bcc ^= c; | |
634 | ||
635 | if (c == DLE) { | |
636 | if (pInfo->last_rx == DLE) { | |
637 | pInfo->last_rx = 0; | |
638 | goto char_to_buf; | |
639 | } | |
640 | pInfo->last_rx = DLE; | |
641 | break; | |
642 | } else if ((c == ETX) && (pInfo->last_rx == DLE)) { | |
643 | if (pInfo->flags & R3964_BCC) { | |
644 | pInfo->state = R3964_WAIT_FOR_BCC; | |
645 | mod_timer(&pInfo->tmr, | |
646 | jiffies + R3964_TO_ZVZ); | |
647 | } else { | |
648 | on_receive_block(pInfo); | |
649 | } | |
650 | } else { | |
651 | pInfo->last_rx = c; | |
1da177e4 | 652 | char_to_buf: |
5e07e1cc JS |
653 | pInfo->rx_buf[pInfo->rx_position++] = c; |
654 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
655 | } | |
656 | } | |
657 | /* else: overflow-msg? BUF_SIZE>MTU; should not happen? */ | |
658 | break; | |
659 | case R3964_WAIT_FOR_BCC: | |
660 | pInfo->last_rx = c; | |
661 | on_receive_block(pInfo); | |
662 | break; | |
663 | } | |
1da177e4 LT |
664 | } |
665 | ||
666 | static void receive_error(struct r3964_info *pInfo, const char flag) | |
667 | { | |
5e07e1cc JS |
668 | switch (flag) { |
669 | case TTY_NORMAL: | |
670 | break; | |
671 | case TTY_BREAK: | |
672 | TRACE_PE("received break"); | |
673 | pInfo->flags |= R3964_BREAK; | |
674 | break; | |
675 | case TTY_PARITY: | |
676 | TRACE_PE("parity error"); | |
677 | pInfo->flags |= R3964_PARITY; | |
678 | break; | |
679 | case TTY_FRAME: | |
680 | TRACE_PE("frame error"); | |
681 | pInfo->flags |= R3964_FRAME; | |
682 | break; | |
683 | case TTY_OVERRUN: | |
684 | TRACE_PE("frame overrun"); | |
685 | pInfo->flags |= R3964_OVERRUN; | |
686 | break; | |
687 | default: | |
688 | TRACE_PE("receive_error - unknown flag %d", flag); | |
689 | pInfo->flags |= R3964_UNKNOWN; | |
690 | break; | |
691 | } | |
1da177e4 LT |
692 | } |
693 | ||
694 | static void on_timeout(unsigned long priv) | |
695 | { | |
5e07e1cc JS |
696 | struct r3964_info *pInfo = (void *)priv; |
697 | ||
698 | switch (pInfo->state) { | |
699 | case R3964_TX_REQUEST: | |
700 | TRACE_PE("TX_REQUEST - timeout"); | |
701 | retry_transmit(pInfo); | |
702 | break; | |
703 | case R3964_WAIT_ZVZ_BEFORE_TX_RETRY: | |
704 | put_char(pInfo, NAK); | |
705 | flush(pInfo); | |
706 | retry_transmit(pInfo); | |
707 | break; | |
708 | case R3964_WAIT_FOR_TX_ACK: | |
709 | TRACE_PE("WAIT_FOR_TX_ACK - timeout"); | |
710 | retry_transmit(pInfo); | |
711 | break; | |
712 | case R3964_WAIT_FOR_RX_BUF: | |
713 | TRACE_PE("WAIT_FOR_RX_BUF - timeout"); | |
714 | put_char(pInfo, NAK); | |
715 | flush(pInfo); | |
716 | pInfo->state = R3964_IDLE; | |
717 | break; | |
718 | case R3964_RECEIVING: | |
719 | TRACE_PE("RECEIVING - timeout after %d chars", | |
720 | pInfo->rx_position); | |
721 | put_char(pInfo, NAK); | |
722 | flush(pInfo); | |
723 | pInfo->state = R3964_IDLE; | |
724 | break; | |
725 | case R3964_WAIT_FOR_RX_REPEAT: | |
726 | TRACE_PE("WAIT_FOR_RX_REPEAT - timeout"); | |
727 | pInfo->state = R3964_IDLE; | |
728 | break; | |
729 | case R3964_WAIT_FOR_BCC: | |
730 | TRACE_PE("WAIT_FOR_BCC - timeout"); | |
731 | put_char(pInfo, NAK); | |
732 | flush(pInfo); | |
733 | pInfo->state = R3964_IDLE; | |
734 | break; | |
735 | } | |
1da177e4 LT |
736 | } |
737 | ||
5e07e1cc JS |
738 | static struct r3964_client_info *findClient(struct r3964_info *pInfo, |
739 | struct pid *pid) | |
1da177e4 | 740 | { |
5e07e1cc JS |
741 | struct r3964_client_info *pClient; |
742 | ||
743 | for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { | |
744 | if (pClient->pid == pid) { | |
745 | return pClient; | |
746 | } | |
747 | } | |
748 | return NULL; | |
1da177e4 LT |
749 | } |
750 | ||
3cec556a | 751 | static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg) |
1da177e4 | 752 | { |
5e07e1cc JS |
753 | struct r3964_client_info *pClient; |
754 | struct r3964_client_info **ppClient; | |
755 | struct r3964_message *pMsg; | |
756 | ||
757 | if ((arg & R3964_SIG_ALL) == 0) { | |
758 | /* Remove client from client list */ | |
759 | for (ppClient = &pInfo->firstClient; *ppClient; | |
760 | ppClient = &(*ppClient)->next) { | |
761 | pClient = *ppClient; | |
762 | ||
763 | if (pClient->pid == pid) { | |
764 | TRACE_PS("removing client %d from client list", | |
765 | pid_nr(pid)); | |
766 | *ppClient = pClient->next; | |
767 | while (pClient->msg_count) { | |
768 | pMsg = remove_msg(pInfo, pClient); | |
769 | if (pMsg) { | |
770 | kfree(pMsg); | |
771 | TRACE_M("enable_signals - msg " | |
772 | "kfree %p", pMsg); | |
773 | } | |
774 | } | |
775 | put_pid(pClient->pid); | |
776 | kfree(pClient); | |
777 | TRACE_M("enable_signals - kfree %p", pClient); | |
778 | return 0; | |
779 | } | |
780 | } | |
781 | return -EINVAL; | |
782 | } else { | |
783 | pClient = findClient(pInfo, pid); | |
784 | if (pClient) { | |
785 | /* update signal options */ | |
786 | pClient->sig_flags = arg; | |
787 | } else { | |
788 | /* add client to client list */ | |
789 | pClient = kmalloc(sizeof(struct r3964_client_info), | |
790 | GFP_KERNEL); | |
791 | TRACE_M("enable_signals - kmalloc %p", pClient); | |
792 | if (pClient == NULL) | |
793 | return -ENOMEM; | |
794 | ||
795 | TRACE_PS("add client %d to client list", pid_nr(pid)); | |
796 | spin_lock_init(&pClient->lock); | |
797 | pClient->sig_flags = arg; | |
798 | pClient->pid = get_pid(pid); | |
799 | pClient->next = pInfo->firstClient; | |
800 | pClient->first_msg = NULL; | |
801 | pClient->last_msg = NULL; | |
802 | pClient->next_block_to_read = NULL; | |
803 | pClient->msg_count = 0; | |
804 | pInfo->firstClient = pClient; | |
805 | } | |
806 | } | |
807 | ||
808 | return 0; | |
1da177e4 LT |
809 | } |
810 | ||
5e07e1cc JS |
811 | static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
812 | unsigned char __user * buf) | |
1da177e4 | 813 | { |
5e07e1cc JS |
814 | struct r3964_client_info *pClient; |
815 | struct r3964_block_header *block; | |
816 | ||
817 | if (!buf) { | |
818 | return -EINVAL; | |
819 | } | |
820 | ||
821 | pClient = findClient(pInfo, pid); | |
822 | if (pClient == NULL) { | |
823 | return -EINVAL; | |
824 | } | |
825 | ||
826 | block = pClient->next_block_to_read; | |
827 | if (!block) { | |
828 | return 0; | |
829 | } else { | |
830 | if (copy_to_user(buf, block->data, block->length)) | |
831 | return -EFAULT; | |
832 | ||
833 | remove_client_block(pInfo, pClient); | |
834 | return block->length; | |
835 | } | |
836 | ||
837 | return -EINVAL; | |
1da177e4 LT |
838 | } |
839 | ||
840 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, | |
5e07e1cc | 841 | int error_code, struct r3964_block_header *pBlock) |
1da177e4 | 842 | { |
5e07e1cc JS |
843 | struct r3964_message *pMsg; |
844 | unsigned long flags; | |
845 | ||
846 | if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) { | |
1da177e4 LT |
847 | queue_the_message: |
848 | ||
5e07e1cc JS |
849 | pMsg = kmalloc(sizeof(struct r3964_message), |
850 | error_code ? GFP_ATOMIC : GFP_KERNEL); | |
851 | TRACE_M("add_msg - kmalloc %p", pMsg); | |
852 | if (pMsg == NULL) { | |
853 | return; | |
854 | } | |
855 | ||
856 | spin_lock_irqsave(&pClient->lock, flags); | |
857 | ||
858 | pMsg->msg_id = msg_id; | |
859 | pMsg->arg = arg; | |
860 | pMsg->error_code = error_code; | |
861 | pMsg->block = pBlock; | |
862 | pMsg->next = NULL; | |
863 | ||
864 | if (pClient->last_msg == NULL) { | |
865 | pClient->first_msg = pClient->last_msg = pMsg; | |
866 | } else { | |
867 | pClient->last_msg->next = pMsg; | |
868 | pClient->last_msg = pMsg; | |
869 | } | |
870 | ||
871 | pClient->msg_count++; | |
872 | ||
873 | if (pBlock != NULL) { | |
874 | pBlock->locks++; | |
875 | } | |
876 | spin_unlock_irqrestore(&pClient->lock, flags); | |
877 | } else { | |
878 | if ((pClient->last_msg->msg_id == R3964_MSG_ACK) | |
879 | && (pClient->last_msg->error_code == R3964_OVERFLOW)) { | |
880 | pClient->last_msg->arg++; | |
881 | TRACE_PE("add_msg - inc prev OVERFLOW-msg"); | |
882 | } else { | |
883 | msg_id = R3964_MSG_ACK; | |
884 | arg = 0; | |
885 | error_code = R3964_OVERFLOW; | |
886 | pBlock = NULL; | |
887 | TRACE_PE("add_msg - queue OVERFLOW-msg"); | |
888 | goto queue_the_message; | |
889 | } | |
890 | } | |
891 | /* Send SIGIO signal to client process: */ | |
892 | if (pClient->sig_flags & R3964_USE_SIGIO) { | |
893 | kill_pid(pClient->pid, SIGIO, 1); | |
894 | } | |
1da177e4 LT |
895 | } |
896 | ||
897 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, | |
5e07e1cc | 898 | struct r3964_client_info *pClient) |
1da177e4 | 899 | { |
5e07e1cc JS |
900 | struct r3964_message *pMsg = NULL; |
901 | unsigned long flags; | |
902 | ||
903 | if (pClient->first_msg) { | |
904 | spin_lock_irqsave(&pClient->lock, flags); | |
905 | ||
906 | pMsg = pClient->first_msg; | |
907 | pClient->first_msg = pMsg->next; | |
908 | if (pClient->first_msg == NULL) { | |
909 | pClient->last_msg = NULL; | |
910 | } | |
911 | ||
912 | pClient->msg_count--; | |
913 | if (pMsg->block) { | |
914 | remove_client_block(pInfo, pClient); | |
915 | pClient->next_block_to_read = pMsg->block; | |
916 | } | |
917 | spin_unlock_irqrestore(&pClient->lock, flags); | |
918 | } | |
919 | return pMsg; | |
1da177e4 LT |
920 | } |
921 | ||
5e07e1cc JS |
922 | static void remove_client_block(struct r3964_info *pInfo, |
923 | struct r3964_client_info *pClient) | |
1da177e4 | 924 | { |
5e07e1cc JS |
925 | struct r3964_block_header *block; |
926 | ||
927 | TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid)); | |
1da177e4 | 928 | |
5e07e1cc JS |
929 | block = pClient->next_block_to_read; |
930 | if (block) { | |
931 | block->locks--; | |
932 | if (block->locks == 0) { | |
933 | remove_from_rx_queue(pInfo, block); | |
934 | } | |
935 | } | |
936 | pClient->next_block_to_read = NULL; | |
937 | } | |
1da177e4 LT |
938 | |
939 | /************************************************************* | |
940 | * Line discipline routines | |
941 | *************************************************************/ | |
942 | ||
943 | static int r3964_open(struct tty_struct *tty) | |
944 | { | |
5e07e1cc JS |
945 | struct r3964_info *pInfo; |
946 | ||
947 | TRACE_L("open"); | |
948 | TRACE_L("tty=%p, PID=%d, disc_data=%p", | |
949 | tty, current->pid, tty->disc_data); | |
950 | ||
951 | pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL); | |
952 | TRACE_M("r3964_open - info kmalloc %p", pInfo); | |
953 | ||
954 | if (!pInfo) { | |
955 | printk(KERN_ERR "r3964: failed to alloc info structure\n"); | |
956 | return -ENOMEM; | |
957 | } | |
958 | ||
959 | pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL); | |
960 | TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf); | |
961 | ||
962 | if (!pInfo->rx_buf) { | |
963 | printk(KERN_ERR "r3964: failed to alloc receive buffer\n"); | |
964 | kfree(pInfo); | |
965 | TRACE_M("r3964_open - info kfree %p", pInfo); | |
966 | return -ENOMEM; | |
967 | } | |
968 | ||
969 | pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL); | |
970 | TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf); | |
971 | ||
972 | if (!pInfo->tx_buf) { | |
973 | printk(KERN_ERR "r3964: failed to alloc transmit buffer\n"); | |
974 | kfree(pInfo->rx_buf); | |
975 | TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf); | |
976 | kfree(pInfo); | |
977 | TRACE_M("r3964_open - info kfree %p", pInfo); | |
978 | return -ENOMEM; | |
979 | } | |
980 | ||
981 | spin_lock_init(&pInfo->lock); | |
982 | pInfo->tty = tty; | |
983 | init_waitqueue_head(&pInfo->read_wait); | |
984 | pInfo->priority = R3964_MASTER; | |
985 | pInfo->rx_first = pInfo->rx_last = NULL; | |
986 | pInfo->tx_first = pInfo->tx_last = NULL; | |
987 | pInfo->rx_position = 0; | |
988 | pInfo->tx_position = 0; | |
989 | pInfo->last_rx = 0; | |
990 | pInfo->blocks_in_rx_queue = 0; | |
991 | pInfo->firstClient = NULL; | |
992 | pInfo->state = R3964_IDLE; | |
993 | pInfo->flags = R3964_DEBUG; | |
994 | pInfo->nRetry = 0; | |
995 | ||
996 | tty->disc_data = pInfo; | |
997 | tty->receive_room = 65536; | |
998 | ||
40565f19 | 999 | setup_timer(&pInfo->tmr, on_timeout, (unsigned long)pInfo); |
5e07e1cc JS |
1000 | |
1001 | return 0; | |
1da177e4 LT |
1002 | } |
1003 | ||
1004 | static void r3964_close(struct tty_struct *tty) | |
1005 | { | |
c9f19e96 | 1006 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1007 | struct r3964_client_info *pClient, *pNext; |
1008 | struct r3964_message *pMsg; | |
1009 | struct r3964_block_header *pHeader, *pNextHeader; | |
1010 | unsigned long flags; | |
1011 | ||
1012 | TRACE_L("close"); | |
1013 | ||
1014 | /* | |
1015 | * Make sure that our task queue isn't activated. If it | |
1016 | * is, take it out of the linked list. | |
1017 | */ | |
1018 | del_timer_sync(&pInfo->tmr); | |
1019 | ||
1020 | /* Remove client-structs and message queues: */ | |
1021 | pClient = pInfo->firstClient; | |
1022 | while (pClient) { | |
1023 | pNext = pClient->next; | |
1024 | while (pClient->msg_count) { | |
1025 | pMsg = remove_msg(pInfo, pClient); | |
1026 | if (pMsg) { | |
1027 | kfree(pMsg); | |
1028 | TRACE_M("r3964_close - msg kfree %p", pMsg); | |
1029 | } | |
1030 | } | |
1031 | put_pid(pClient->pid); | |
1032 | kfree(pClient); | |
1033 | TRACE_M("r3964_close - client kfree %p", pClient); | |
1034 | pClient = pNext; | |
1035 | } | |
1036 | /* Remove jobs from tx_queue: */ | |
1037 | spin_lock_irqsave(&pInfo->lock, flags); | |
1038 | pHeader = pInfo->tx_first; | |
1039 | pInfo->tx_first = pInfo->tx_last = NULL; | |
1da177e4 | 1040 | spin_unlock_irqrestore(&pInfo->lock, flags); |
5e07e1cc JS |
1041 | |
1042 | while (pHeader) { | |
1043 | pNextHeader = pHeader->next; | |
1044 | kfree(pHeader); | |
1045 | pHeader = pNextHeader; | |
1da177e4 LT |
1046 | } |
1047 | ||
5e07e1cc JS |
1048 | /* Free buffers: */ |
1049 | wake_up_interruptible(&pInfo->read_wait); | |
1050 | kfree(pInfo->rx_buf); | |
1051 | TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf); | |
1052 | kfree(pInfo->tx_buf); | |
1053 | TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf); | |
1054 | kfree(pInfo); | |
1055 | TRACE_M("r3964_close - info kfree %p", pInfo); | |
1da177e4 LT |
1056 | } |
1057 | ||
1058 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, | |
5e07e1cc | 1059 | unsigned char __user * buf, size_t nr) |
1da177e4 | 1060 | { |
c9f19e96 | 1061 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1062 | struct r3964_client_info *pClient; |
1063 | struct r3964_message *pMsg; | |
1064 | struct r3964_client_message theMsg; | |
eca41044 | 1065 | int ret; |
5e07e1cc JS |
1066 | |
1067 | TRACE_L("read()"); | |
1068 | ||
ec79d605 | 1069 | tty_lock(); |
04f378b1 | 1070 | |
5e07e1cc JS |
1071 | pClient = findClient(pInfo, task_pid(current)); |
1072 | if (pClient) { | |
1073 | pMsg = remove_msg(pInfo, pClient); | |
1074 | if (pMsg == NULL) { | |
1075 | /* no messages available. */ | |
1076 | if (file->f_flags & O_NONBLOCK) { | |
eca41044 JS |
1077 | ret = -EAGAIN; |
1078 | goto unlock; | |
5e07e1cc JS |
1079 | } |
1080 | /* block until there is a message: */ | |
be1bc288 | 1081 | wait_event_interruptible_tty(pInfo->read_wait, |
6defec13 | 1082 | (pMsg = remove_msg(pInfo, pClient))); |
5e07e1cc JS |
1083 | } |
1084 | ||
1085 | /* If we still haven't got a message, we must have been signalled */ | |
1086 | ||
04f378b1 | 1087 | if (!pMsg) { |
eca41044 JS |
1088 | ret = -EINTR; |
1089 | goto unlock; | |
04f378b1 | 1090 | } |
5e07e1cc JS |
1091 | |
1092 | /* deliver msg to client process: */ | |
1093 | theMsg.msg_id = pMsg->msg_id; | |
1094 | theMsg.arg = pMsg->arg; | |
1095 | theMsg.error_code = pMsg->error_code; | |
eca41044 | 1096 | ret = sizeof(struct r3964_client_message); |
5e07e1cc JS |
1097 | |
1098 | kfree(pMsg); | |
1099 | TRACE_M("r3964_read - msg kfree %p", pMsg); | |
1100 | ||
eca41044 JS |
1101 | if (copy_to_user(buf, &theMsg, ret)) { |
1102 | ret = -EFAULT; | |
1103 | goto unlock; | |
04f378b1 | 1104 | } |
5e07e1cc | 1105 | |
eca41044 JS |
1106 | TRACE_PS("read - return %d", ret); |
1107 | goto unlock; | |
5e07e1cc | 1108 | } |
eca41044 JS |
1109 | ret = -EPERM; |
1110 | unlock: | |
ec79d605 | 1111 | tty_unlock(); |
eca41044 | 1112 | return ret; |
1da177e4 LT |
1113 | } |
1114 | ||
5e07e1cc | 1115 | static ssize_t r3964_write(struct tty_struct *tty, struct file *file, |
1da177e4 LT |
1116 | const unsigned char *data, size_t count) |
1117 | { | |
c9f19e96 | 1118 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1119 | struct r3964_block_header *pHeader; |
1120 | struct r3964_client_info *pClient; | |
1121 | unsigned char *new_data; | |
1122 | ||
1123 | TRACE_L("write request, %d characters", count); | |
1da177e4 LT |
1124 | /* |
1125 | * Verify the pointers | |
1126 | */ | |
1127 | ||
5e07e1cc JS |
1128 | if (!pInfo) |
1129 | return -EIO; | |
1da177e4 LT |
1130 | |
1131 | /* | |
1132 | * Ensure that the caller does not wish to send too much. | |
1133 | */ | |
5e07e1cc JS |
1134 | if (count > R3964_MTU) { |
1135 | if (pInfo->flags & R3964_DEBUG) { | |
1136 | TRACE_L(KERN_WARNING "r3964_write: truncating user " | |
1137 | "packet from %u to mtu %d", count, R3964_MTU); | |
1138 | } | |
1139 | count = R3964_MTU; | |
1140 | } | |
1da177e4 LT |
1141 | /* |
1142 | * Allocate a buffer for the data and copy it from the buffer with header prepended | |
1143 | */ | |
5e07e1cc JS |
1144 | new_data = kmalloc(count + sizeof(struct r3964_block_header), |
1145 | GFP_KERNEL); | |
1146 | TRACE_M("r3964_write - kmalloc %p", new_data); | |
1147 | if (new_data == NULL) { | |
1148 | if (pInfo->flags & R3964_DEBUG) { | |
1149 | printk(KERN_ERR "r3964_write: no memory\n"); | |
1150 | } | |
1151 | return -ENOSPC; | |
1152 | } | |
1153 | ||
1154 | pHeader = (struct r3964_block_header *)new_data; | |
1155 | pHeader->data = new_data + sizeof(struct r3964_block_header); | |
1156 | pHeader->length = count; | |
1157 | pHeader->locks = 0; | |
1158 | pHeader->owner = NULL; | |
1159 | ||
ec79d605 | 1160 | tty_lock(); |
04f378b1 | 1161 | |
5e07e1cc JS |
1162 | pClient = findClient(pInfo, task_pid(current)); |
1163 | if (pClient) { | |
1164 | pHeader->owner = pClient; | |
1165 | } | |
1166 | ||
1167 | memcpy(pHeader->data, data, count); /* We already verified this */ | |
1168 | ||
1169 | if (pInfo->flags & R3964_DEBUG) { | |
1170 | dump_block(pHeader->data, count); | |
1171 | } | |
1da177e4 LT |
1172 | |
1173 | /* | |
1174 | * Add buffer to transmit-queue: | |
1175 | */ | |
5e07e1cc JS |
1176 | add_tx_queue(pInfo, pHeader); |
1177 | trigger_transmit(pInfo); | |
1178 | ||
ec79d605 | 1179 | tty_unlock(); |
04f378b1 | 1180 | |
5e07e1cc | 1181 | return 0; |
1da177e4 LT |
1182 | } |
1183 | ||
5e07e1cc JS |
1184 | static int r3964_ioctl(struct tty_struct *tty, struct file *file, |
1185 | unsigned int cmd, unsigned long arg) | |
1da177e4 | 1186 | { |
c9f19e96 | 1187 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1188 | if (pInfo == NULL) |
1189 | return -EINVAL; | |
1190 | switch (cmd) { | |
1191 | case R3964_ENABLE_SIGNALS: | |
1192 | return enable_signals(pInfo, task_pid(current), arg); | |
1193 | case R3964_SETPRIORITY: | |
1194 | if (arg < R3964_MASTER || arg > R3964_SLAVE) | |
1195 | return -EINVAL; | |
1196 | pInfo->priority = arg & 0xff; | |
1197 | return 0; | |
1198 | case R3964_USE_BCC: | |
1199 | if (arg) | |
1200 | pInfo->flags |= R3964_BCC; | |
1201 | else | |
1202 | pInfo->flags &= ~R3964_BCC; | |
1203 | return 0; | |
1204 | case R3964_READ_TELEGRAM: | |
1205 | return read_telegram(pInfo, task_pid(current), | |
1206 | (unsigned char __user *)arg); | |
1207 | default: | |
1208 | return -ENOIOCTLCMD; | |
1209 | } | |
1da177e4 LT |
1210 | } |
1211 | ||
5e07e1cc | 1212 | static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old) |
1da177e4 | 1213 | { |
5e07e1cc | 1214 | TRACE_L("set_termios"); |
1da177e4 LT |
1215 | } |
1216 | ||
1217 | /* Called without the kernel lock held - fine */ | |
5e07e1cc JS |
1218 | static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, |
1219 | struct poll_table_struct *wait) | |
1da177e4 | 1220 | { |
c9f19e96 | 1221 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1222 | struct r3964_client_info *pClient; |
1223 | struct r3964_message *pMsg = NULL; | |
1224 | unsigned long flags; | |
1225 | int result = POLLOUT; | |
1226 | ||
1227 | TRACE_L("POLL"); | |
1228 | ||
1229 | pClient = findClient(pInfo, task_pid(current)); | |
1230 | if (pClient) { | |
1231 | poll_wait(file, &pInfo->read_wait, wait); | |
1232 | spin_lock_irqsave(&pInfo->lock, flags); | |
1233 | pMsg = pClient->first_msg; | |
1234 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
1235 | if (pMsg) | |
1236 | result |= POLLIN | POLLRDNORM; | |
1237 | } else { | |
1238 | result = -EINVAL; | |
1239 | } | |
1240 | return result; | |
1da177e4 LT |
1241 | } |
1242 | ||
1243 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, | |
5e07e1cc | 1244 | char *fp, int count) |
1da177e4 | 1245 | { |
c9f19e96 | 1246 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1247 | const unsigned char *p; |
1248 | char *f, flags = 0; | |
1249 | int i; | |
1250 | ||
1251 | for (i = count, p = cp, f = fp; i; i--, p++) { | |
1252 | if (f) | |
1253 | flags = *f++; | |
1254 | if (flags == TTY_NORMAL) { | |
1255 | receive_char(pInfo, *p); | |
1256 | } else { | |
1257 | receive_error(pInfo, flags); | |
1258 | } | |
1259 | ||
1260 | } | |
1da177e4 LT |
1261 | } |
1262 | ||
1da177e4 LT |
1263 | MODULE_LICENSE("GPL"); |
1264 | MODULE_ALIAS_LDISC(N_R3964); |