Commit | Line | Data |
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1da177e4 LT |
1 | /* r3964 linediscipline for linux |
2 | * | |
3 | * ----------------------------------------------------------- | |
4 | * Copyright by | |
5 | * Philips Automation Projects | |
6 | * Kassel (Germany) | |
7 | * http://www.pap-philips.de | |
8 | * ----------------------------------------------------------- | |
9 | * This software may be used and distributed according to the terms of | |
10 | * the GNU General Public License, incorporated herein by reference. | |
11 | * | |
12 | * Author: | |
13 | * L. Haag | |
14 | * | |
15 | * $Log: n_r3964.c,v $ | |
16 | * Revision 1.10 2001/03/18 13:02:24 dwmw2 | |
17 | * Fix timer usage, use spinlocks properly. | |
18 | * | |
19 | * Revision 1.9 2001/03/18 12:52:14 dwmw2 | |
20 | * Merge changes in 2.4.2 | |
21 | * | |
22 | * Revision 1.8 2000/03/23 14:14:54 dwmw2 | |
23 | * Fix race in sleeping in r3964_read() | |
24 | * | |
25 | * Revision 1.7 1999/28/08 11:41:50 dwmw2 | |
26 | * Port to 2.3 kernel | |
27 | * | |
28 | * Revision 1.6 1998/09/30 00:40:40 dwmw2 | |
29 | * Fixed compilation on 2.0.x kernels | |
30 | * Updated to newly registered tty-ldisc number 9 | |
31 | * | |
32 | * Revision 1.5 1998/09/04 21:57:36 dwmw2 | |
33 | * Signal handling bug fixes, port to 2.1.x. | |
34 | * | |
35 | * Revision 1.4 1998/04/02 20:26:59 lhaag | |
36 | * select, blocking, ... | |
37 | * | |
38 | * Revision 1.3 1998/02/12 18:58:43 root | |
39 | * fixed some memory leaks | |
40 | * calculation of checksum characters | |
41 | * | |
42 | * Revision 1.2 1998/02/07 13:03:34 root | |
43 | * ioctl read_telegram | |
44 | * | |
45 | * Revision 1.1 1998/02/06 19:21:03 root | |
46 | * Initial revision | |
47 | * | |
48 | * | |
49 | */ | |
50 | ||
51 | #include <linux/module.h> | |
52 | #include <linux/kernel.h> | |
53 | #include <linux/sched.h> | |
54 | #include <linux/types.h> | |
55 | #include <linux/fcntl.h> | |
56 | #include <linux/interrupt.h> | |
57 | #include <linux/ptrace.h> | |
58 | #include <linux/ioport.h> | |
59 | #include <linux/in.h> | |
60 | #include <linux/slab.h> | |
405f5571 | 61 | #include <linux/smp_lock.h> |
1da177e4 LT |
62 | #include <linux/tty.h> |
63 | #include <linux/errno.h> | |
5e07e1cc JS |
64 | #include <linux/string.h> /* used in new tty drivers */ |
65 | #include <linux/signal.h> /* used in new tty drivers */ | |
1da177e4 LT |
66 | #include <linux/ioctl.h> |
67 | #include <linux/n_r3964.h> | |
68 | #include <linux/poll.h> | |
69 | #include <linux/init.h> | |
70 | #include <asm/uaccess.h> | |
71 | ||
5e07e1cc | 72 | /*#define DEBUG_QUEUE*/ |
1da177e4 LT |
73 | |
74 | /* Log successful handshake and protocol operations */ | |
5e07e1cc | 75 | /*#define DEBUG_PROTO_S*/ |
1da177e4 LT |
76 | |
77 | /* Log handshake and protocol errors: */ | |
5e07e1cc | 78 | /*#define DEBUG_PROTO_E*/ |
1da177e4 LT |
79 | |
80 | /* Log Linediscipline operations (open, close, read, write...): */ | |
5e07e1cc | 81 | /*#define DEBUG_LDISC*/ |
1da177e4 LT |
82 | |
83 | /* Log module and memory operations (init, cleanup; kmalloc, kfree): */ | |
5e07e1cc | 84 | /*#define DEBUG_MODUL*/ |
1da177e4 LT |
85 | |
86 | /* Macro helpers for debug output: */ | |
5e07e1cc | 87 | #define TRACE(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 LT |
88 | |
89 | #ifdef DEBUG_MODUL | |
5e07e1cc | 90 | #define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 91 | #else |
5e07e1cc | 92 | #define TRACE_M(fmt, arg...) do {} while (0) |
1da177e4 | 93 | #endif |
1da177e4 | 94 | #ifdef DEBUG_PROTO_S |
5e07e1cc | 95 | #define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 96 | #else |
5e07e1cc | 97 | #define TRACE_PS(fmt, arg...) do {} while (0) |
1da177e4 | 98 | #endif |
1da177e4 | 99 | #ifdef DEBUG_PROTO_E |
5e07e1cc | 100 | #define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 101 | #else |
5e07e1cc | 102 | #define TRACE_PE(fmt, arg...) do {} while (0) |
1da177e4 | 103 | #endif |
1da177e4 | 104 | #ifdef DEBUG_LDISC |
5e07e1cc | 105 | #define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 106 | #else |
5e07e1cc | 107 | #define TRACE_L(fmt, arg...) do {} while (0) |
1da177e4 | 108 | #endif |
1da177e4 | 109 | #ifdef DEBUG_QUEUE |
5e07e1cc | 110 | #define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 111 | #else |
5e07e1cc | 112 | #define TRACE_Q(fmt, arg...) do {} while (0) |
1da177e4 | 113 | #endif |
1da177e4 LT |
114 | static void add_tx_queue(struct r3964_info *, struct r3964_block_header *); |
115 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code); | |
116 | static void put_char(struct r3964_info *pInfo, unsigned char ch); | |
117 | static void trigger_transmit(struct r3964_info *pInfo); | |
118 | static void retry_transmit(struct r3964_info *pInfo); | |
119 | static void transmit_block(struct r3964_info *pInfo); | |
120 | static void receive_char(struct r3964_info *pInfo, const unsigned char c); | |
121 | static void receive_error(struct r3964_info *pInfo, const char flag); | |
122 | static void on_timeout(unsigned long priv); | |
3cec556a | 123 | static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg); |
5e07e1cc JS |
124 | static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
125 | unsigned char __user * buf); | |
1da177e4 | 126 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
5e07e1cc JS |
127 | int error_code, struct r3964_block_header *pBlock); |
128 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, | |
129 | struct r3964_client_info *pClient); | |
130 | static void remove_client_block(struct r3964_info *pInfo, | |
131 | struct r3964_client_info *pClient); | |
1da177e4 | 132 | |
5e07e1cc | 133 | static int r3964_open(struct tty_struct *tty); |
1da177e4 LT |
134 | static void r3964_close(struct tty_struct *tty); |
135 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, | |
5e07e1cc JS |
136 | unsigned char __user * buf, size_t nr); |
137 | static ssize_t r3964_write(struct tty_struct *tty, struct file *file, | |
138 | const unsigned char *buf, size_t nr); | |
139 | static int r3964_ioctl(struct tty_struct *tty, struct file *file, | |
140 | unsigned int cmd, unsigned long arg); | |
141 | static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old); | |
142 | static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, | |
143 | struct poll_table_struct *wait); | |
1da177e4 | 144 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
5e07e1cc | 145 | char *fp, int count); |
1da177e4 | 146 | |
a352def2 | 147 | static struct tty_ldisc_ops tty_ldisc_N_R3964 = { |
5e07e1cc JS |
148 | .owner = THIS_MODULE, |
149 | .magic = TTY_LDISC_MAGIC, | |
150 | .name = "R3964", | |
151 | .open = r3964_open, | |
152 | .close = r3964_close, | |
153 | .read = r3964_read, | |
154 | .write = r3964_write, | |
155 | .ioctl = r3964_ioctl, | |
1da177e4 | 156 | .set_termios = r3964_set_termios, |
5e07e1cc | 157 | .poll = r3964_poll, |
1da177e4 | 158 | .receive_buf = r3964_receive_buf, |
1da177e4 LT |
159 | }; |
160 | ||
1da177e4 LT |
161 | static void dump_block(const unsigned char *block, unsigned int length) |
162 | { | |
5e07e1cc JS |
163 | unsigned int i, j; |
164 | char linebuf[16 * 3 + 1]; | |
165 | ||
166 | for (i = 0; i < length; i += 16) { | |
167 | for (j = 0; (j < 16) && (j + i < length); j++) { | |
168 | sprintf(linebuf + 3 * j, "%02x ", block[i + j]); | |
169 | } | |
170 | linebuf[3 * j] = '\0'; | |
171 | TRACE_PS("%s", linebuf); | |
172 | } | |
1da177e4 LT |
173 | } |
174 | ||
1da177e4 LT |
175 | /************************************************************* |
176 | * Driver initialisation | |
177 | *************************************************************/ | |
178 | ||
1da177e4 LT |
179 | /************************************************************* |
180 | * Module support routines | |
181 | *************************************************************/ | |
182 | ||
183 | static void __exit r3964_exit(void) | |
184 | { | |
5e07e1cc JS |
185 | int status; |
186 | ||
187 | TRACE_M("cleanup_module()"); | |
188 | ||
189 | status = tty_unregister_ldisc(N_R3964); | |
190 | ||
191 | if (status != 0) { | |
192 | printk(KERN_ERR "r3964: error unregistering linediscipline: " | |
193 | "%d\n", status); | |
194 | } else { | |
195 | TRACE_L("linediscipline successfully unregistered"); | |
196 | } | |
1da177e4 LT |
197 | } |
198 | ||
199 | static int __init r3964_init(void) | |
200 | { | |
5e07e1cc JS |
201 | int status; |
202 | ||
203 | printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n"); | |
204 | ||
205 | /* | |
206 | * Register the tty line discipline | |
207 | */ | |
208 | ||
209 | status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964); | |
210 | if (status == 0) { | |
211 | TRACE_L("line discipline %d registered", N_R3964); | |
212 | TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags, | |
213 | tty_ldisc_N_R3964.num); | |
214 | TRACE_L("open=%p", tty_ldisc_N_R3964.open); | |
215 | TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964); | |
216 | } else { | |
217 | printk(KERN_ERR "r3964: error registering line discipline: " | |
218 | "%d\n", status); | |
219 | } | |
220 | return status; | |
1da177e4 LT |
221 | } |
222 | ||
223 | module_init(r3964_init); | |
224 | module_exit(r3964_exit); | |
225 | ||
1da177e4 LT |
226 | /************************************************************* |
227 | * Protocol implementation routines | |
228 | *************************************************************/ | |
229 | ||
5e07e1cc JS |
230 | static void add_tx_queue(struct r3964_info *pInfo, |
231 | struct r3964_block_header *pHeader) | |
1da177e4 | 232 | { |
5e07e1cc JS |
233 | unsigned long flags; |
234 | ||
235 | spin_lock_irqsave(&pInfo->lock, flags); | |
236 | ||
237 | pHeader->next = NULL; | |
238 | ||
239 | if (pInfo->tx_last == NULL) { | |
240 | pInfo->tx_first = pInfo->tx_last = pHeader; | |
241 | } else { | |
242 | pInfo->tx_last->next = pHeader; | |
243 | pInfo->tx_last = pHeader; | |
244 | } | |
245 | ||
246 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
247 | ||
248 | TRACE_Q("add_tx_queue %p, length %d, tx_first = %p", | |
249 | pHeader, pHeader->length, pInfo->tx_first); | |
1da177e4 LT |
250 | } |
251 | ||
252 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code) | |
253 | { | |
5e07e1cc JS |
254 | struct r3964_block_header *pHeader; |
255 | unsigned long flags; | |
1da177e4 | 256 | #ifdef DEBUG_QUEUE |
5e07e1cc | 257 | struct r3964_block_header *pDump; |
1da177e4 | 258 | #endif |
1da177e4 | 259 | |
5e07e1cc JS |
260 | pHeader = pInfo->tx_first; |
261 | ||
262 | if (pHeader == NULL) | |
263 | return; | |
1da177e4 LT |
264 | |
265 | #ifdef DEBUG_QUEUE | |
5e07e1cc JS |
266 | printk("r3964: remove_from_tx_queue: %p, length %u - ", |
267 | pHeader, pHeader->length); | |
268 | for (pDump = pHeader; pDump; pDump = pDump->next) | |
269 | printk("%p ", pDump); | |
270 | printk("\n"); | |
1da177e4 LT |
271 | #endif |
272 | ||
5e07e1cc JS |
273 | if (pHeader->owner) { |
274 | if (error_code) { | |
275 | add_msg(pHeader->owner, R3964_MSG_ACK, 0, | |
276 | error_code, NULL); | |
277 | } else { | |
278 | add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length, | |
279 | error_code, NULL); | |
280 | } | |
281 | wake_up_interruptible(&pInfo->read_wait); | |
282 | } | |
283 | ||
284 | spin_lock_irqsave(&pInfo->lock, flags); | |
285 | ||
286 | pInfo->tx_first = pHeader->next; | |
287 | if (pInfo->tx_first == NULL) { | |
288 | pInfo->tx_last = NULL; | |
289 | } | |
290 | ||
291 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
292 | ||
293 | kfree(pHeader); | |
294 | TRACE_M("remove_from_tx_queue - kfree %p", pHeader); | |
1da177e4 | 295 | |
5e07e1cc JS |
296 | TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p", |
297 | pInfo->tx_first, pInfo->tx_last); | |
1da177e4 LT |
298 | } |
299 | ||
5e07e1cc JS |
300 | static void add_rx_queue(struct r3964_info *pInfo, |
301 | struct r3964_block_header *pHeader) | |
1da177e4 | 302 | { |
5e07e1cc JS |
303 | unsigned long flags; |
304 | ||
305 | spin_lock_irqsave(&pInfo->lock, flags); | |
306 | ||
307 | pHeader->next = NULL; | |
308 | ||
309 | if (pInfo->rx_last == NULL) { | |
310 | pInfo->rx_first = pInfo->rx_last = pHeader; | |
311 | } else { | |
312 | pInfo->rx_last->next = pHeader; | |
313 | pInfo->rx_last = pHeader; | |
314 | } | |
315 | pInfo->blocks_in_rx_queue++; | |
316 | ||
317 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
318 | ||
319 | TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d", | |
320 | pHeader, pHeader->length, | |
321 | pInfo->rx_first, pInfo->blocks_in_rx_queue); | |
1da177e4 LT |
322 | } |
323 | ||
324 | static void remove_from_rx_queue(struct r3964_info *pInfo, | |
5e07e1cc | 325 | struct r3964_block_header *pHeader) |
1da177e4 | 326 | { |
5e07e1cc JS |
327 | unsigned long flags; |
328 | struct r3964_block_header *pFind; | |
329 | ||
330 | if (pHeader == NULL) | |
331 | return; | |
332 | ||
333 | TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", | |
334 | pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); | |
335 | TRACE_Q("remove_from_rx_queue: %p, length %u", | |
336 | pHeader, pHeader->length); | |
337 | ||
338 | spin_lock_irqsave(&pInfo->lock, flags); | |
339 | ||
340 | if (pInfo->rx_first == pHeader) { | |
341 | /* Remove the first block in the linked list: */ | |
342 | pInfo->rx_first = pHeader->next; | |
343 | ||
344 | if (pInfo->rx_first == NULL) { | |
345 | pInfo->rx_last = NULL; | |
346 | } | |
347 | pInfo->blocks_in_rx_queue--; | |
348 | } else { | |
349 | /* Find block to remove: */ | |
350 | for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) { | |
351 | if (pFind->next == pHeader) { | |
352 | /* Got it. */ | |
353 | pFind->next = pHeader->next; | |
354 | pInfo->blocks_in_rx_queue--; | |
355 | if (pFind->next == NULL) { | |
356 | /* Oh, removed the last one! */ | |
357 | pInfo->rx_last = pFind; | |
358 | } | |
359 | break; | |
360 | } | |
361 | } | |
362 | } | |
363 | ||
364 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
365 | ||
366 | kfree(pHeader); | |
367 | TRACE_M("remove_from_rx_queue - kfree %p", pHeader); | |
368 | ||
369 | TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", | |
370 | pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); | |
1da177e4 LT |
371 | } |
372 | ||
373 | static void put_char(struct r3964_info *pInfo, unsigned char ch) | |
374 | { | |
5e07e1cc | 375 | struct tty_struct *tty = pInfo->tty; |
f34d7a5b | 376 | /* FIXME: put_char should not be called from an IRQ */ |
51383f69 | 377 | tty_put_char(tty, ch); |
5e07e1cc | 378 | pInfo->bcc ^= ch; |
1da177e4 LT |
379 | } |
380 | ||
381 | static void flush(struct r3964_info *pInfo) | |
382 | { | |
5e07e1cc | 383 | struct tty_struct *tty = pInfo->tty; |
1da177e4 | 384 | |
f34d7a5b | 385 | if (tty == NULL || tty->ops->flush_chars == NULL) |
5e07e1cc | 386 | return; |
f34d7a5b | 387 | tty->ops->flush_chars(tty); |
1da177e4 LT |
388 | } |
389 | ||
390 | static void trigger_transmit(struct r3964_info *pInfo) | |
391 | { | |
5e07e1cc | 392 | unsigned long flags; |
1da177e4 | 393 | |
5e07e1cc | 394 | spin_lock_irqsave(&pInfo->lock, flags); |
1da177e4 | 395 | |
5e07e1cc JS |
396 | if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) { |
397 | pInfo->state = R3964_TX_REQUEST; | |
398 | pInfo->nRetry = 0; | |
399 | pInfo->flags &= ~R3964_ERROR; | |
400 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
1da177e4 | 401 | |
5e07e1cc | 402 | spin_unlock_irqrestore(&pInfo->lock, flags); |
1da177e4 | 403 | |
5e07e1cc | 404 | TRACE_PS("trigger_transmit - sent STX"); |
1da177e4 | 405 | |
5e07e1cc JS |
406 | put_char(pInfo, STX); |
407 | flush(pInfo); | |
1da177e4 | 408 | |
5e07e1cc JS |
409 | pInfo->bcc = 0; |
410 | } else { | |
411 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
412 | } | |
1da177e4 LT |
413 | } |
414 | ||
415 | static void retry_transmit(struct r3964_info *pInfo) | |
416 | { | |
5e07e1cc JS |
417 | if (pInfo->nRetry < R3964_MAX_RETRIES) { |
418 | TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry); | |
419 | pInfo->bcc = 0; | |
420 | put_char(pInfo, STX); | |
421 | flush(pInfo); | |
422 | pInfo->state = R3964_TX_REQUEST; | |
423 | pInfo->nRetry++; | |
424 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
425 | } else { | |
426 | TRACE_PE("transmission failed after %d retries", | |
427 | R3964_MAX_RETRIES); | |
428 | ||
429 | remove_from_tx_queue(pInfo, R3964_TX_FAIL); | |
430 | ||
431 | put_char(pInfo, NAK); | |
432 | flush(pInfo); | |
433 | pInfo->state = R3964_IDLE; | |
434 | ||
435 | trigger_transmit(pInfo); | |
436 | } | |
1da177e4 LT |
437 | } |
438 | ||
1da177e4 LT |
439 | static void transmit_block(struct r3964_info *pInfo) |
440 | { | |
5e07e1cc JS |
441 | struct tty_struct *tty = pInfo->tty; |
442 | struct r3964_block_header *pBlock = pInfo->tx_first; | |
443 | int room = 0; | |
444 | ||
f34d7a5b | 445 | if (tty == NULL || pBlock == NULL) { |
5e07e1cc JS |
446 | return; |
447 | } | |
448 | ||
f34d7a5b | 449 | room = tty_write_room(tty); |
5e07e1cc JS |
450 | |
451 | TRACE_PS("transmit_block %p, room %d, length %d", | |
452 | pBlock, room, pBlock->length); | |
453 | ||
454 | while (pInfo->tx_position < pBlock->length) { | |
455 | if (room < 2) | |
456 | break; | |
457 | ||
458 | if (pBlock->data[pInfo->tx_position] == DLE) { | |
459 | /* send additional DLE char: */ | |
460 | put_char(pInfo, DLE); | |
461 | } | |
462 | put_char(pInfo, pBlock->data[pInfo->tx_position++]); | |
463 | ||
464 | room--; | |
465 | } | |
466 | ||
467 | if ((pInfo->tx_position == pBlock->length) && (room >= 3)) { | |
468 | put_char(pInfo, DLE); | |
469 | put_char(pInfo, ETX); | |
470 | if (pInfo->flags & R3964_BCC) { | |
471 | put_char(pInfo, pInfo->bcc); | |
472 | } | |
473 | pInfo->state = R3964_WAIT_FOR_TX_ACK; | |
474 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
475 | } | |
476 | flush(pInfo); | |
1da177e4 LT |
477 | } |
478 | ||
479 | static void on_receive_block(struct r3964_info *pInfo) | |
480 | { | |
5e07e1cc JS |
481 | unsigned int length; |
482 | struct r3964_client_info *pClient; | |
483 | struct r3964_block_header *pBlock; | |
484 | ||
485 | length = pInfo->rx_position; | |
486 | ||
487 | /* compare byte checksum characters: */ | |
488 | if (pInfo->flags & R3964_BCC) { | |
489 | if (pInfo->bcc != pInfo->last_rx) { | |
490 | TRACE_PE("checksum error - got %x but expected %x", | |
491 | pInfo->last_rx, pInfo->bcc); | |
492 | pInfo->flags |= R3964_CHECKSUM; | |
493 | } | |
494 | } | |
495 | ||
496 | /* check for errors (parity, overrun,...): */ | |
497 | if (pInfo->flags & R3964_ERROR) { | |
498 | TRACE_PE("on_receive_block - transmission failed error %x", | |
499 | pInfo->flags & R3964_ERROR); | |
500 | ||
501 | put_char(pInfo, NAK); | |
502 | flush(pInfo); | |
503 | if (pInfo->nRetry < R3964_MAX_RETRIES) { | |
504 | pInfo->state = R3964_WAIT_FOR_RX_REPEAT; | |
505 | pInfo->nRetry++; | |
506 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC); | |
507 | } else { | |
508 | TRACE_PE("on_receive_block - failed after max retries"); | |
509 | pInfo->state = R3964_IDLE; | |
510 | } | |
511 | return; | |
512 | } | |
513 | ||
514 | /* received block; submit DLE: */ | |
515 | put_char(pInfo, DLE); | |
516 | flush(pInfo); | |
517 | del_timer_sync(&pInfo->tmr); | |
518 | TRACE_PS(" rx success: got %d chars", length); | |
519 | ||
520 | /* prepare struct r3964_block_header: */ | |
521 | pBlock = kmalloc(length + sizeof(struct r3964_block_header), | |
522 | GFP_KERNEL); | |
523 | TRACE_M("on_receive_block - kmalloc %p", pBlock); | |
524 | ||
525 | if (pBlock == NULL) | |
526 | return; | |
527 | ||
528 | pBlock->length = length; | |
529 | pBlock->data = ((unsigned char *)pBlock) + | |
530 | sizeof(struct r3964_block_header); | |
531 | pBlock->locks = 0; | |
532 | pBlock->next = NULL; | |
533 | pBlock->owner = NULL; | |
534 | ||
535 | memcpy(pBlock->data, pInfo->rx_buf, length); | |
536 | ||
537 | /* queue block into rx_queue: */ | |
538 | add_rx_queue(pInfo, pBlock); | |
539 | ||
540 | /* notify attached client processes: */ | |
541 | for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { | |
542 | if (pClient->sig_flags & R3964_SIG_DATA) { | |
543 | add_msg(pClient, R3964_MSG_DATA, length, R3964_OK, | |
544 | pBlock); | |
545 | } | |
546 | } | |
547 | wake_up_interruptible(&pInfo->read_wait); | |
1da177e4 | 548 | |
5e07e1cc JS |
549 | pInfo->state = R3964_IDLE; |
550 | ||
551 | trigger_transmit(pInfo); | |
552 | } | |
1da177e4 LT |
553 | |
554 | static void receive_char(struct r3964_info *pInfo, const unsigned char c) | |
555 | { | |
5e07e1cc JS |
556 | switch (pInfo->state) { |
557 | case R3964_TX_REQUEST: | |
558 | if (c == DLE) { | |
559 | TRACE_PS("TX_REQUEST - got DLE"); | |
560 | ||
561 | pInfo->state = R3964_TRANSMITTING; | |
562 | pInfo->tx_position = 0; | |
563 | ||
564 | transmit_block(pInfo); | |
565 | } else if (c == STX) { | |
566 | if (pInfo->nRetry == 0) { | |
567 | TRACE_PE("TX_REQUEST - init conflict"); | |
568 | if (pInfo->priority == R3964_SLAVE) { | |
569 | goto start_receiving; | |
570 | } | |
571 | } else { | |
572 | TRACE_PE("TX_REQUEST - secondary init " | |
573 | "conflict!? Switching to SLAVE mode " | |
574 | "for next rx."); | |
575 | goto start_receiving; | |
576 | } | |
577 | } else { | |
578 | TRACE_PE("TX_REQUEST - char != DLE: %x", c); | |
579 | retry_transmit(pInfo); | |
580 | } | |
581 | break; | |
582 | case R3964_TRANSMITTING: | |
583 | if (c == NAK) { | |
584 | TRACE_PE("TRANSMITTING - got NAK"); | |
585 | retry_transmit(pInfo); | |
586 | } else { | |
587 | TRACE_PE("TRANSMITTING - got invalid char"); | |
588 | ||
589 | pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY; | |
590 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
591 | } | |
592 | break; | |
593 | case R3964_WAIT_FOR_TX_ACK: | |
594 | if (c == DLE) { | |
595 | TRACE_PS("WAIT_FOR_TX_ACK - got DLE"); | |
596 | remove_from_tx_queue(pInfo, R3964_OK); | |
597 | ||
598 | pInfo->state = R3964_IDLE; | |
599 | trigger_transmit(pInfo); | |
600 | } else { | |
601 | retry_transmit(pInfo); | |
602 | } | |
603 | break; | |
604 | case R3964_WAIT_FOR_RX_REPEAT: | |
605 | /* FALLTROUGH */ | |
606 | case R3964_IDLE: | |
607 | if (c == STX) { | |
608 | /* Prevent rx_queue from overflow: */ | |
609 | if (pInfo->blocks_in_rx_queue >= | |
610 | R3964_MAX_BLOCKS_IN_RX_QUEUE) { | |
611 | TRACE_PE("IDLE - got STX but no space in " | |
612 | "rx_queue!"); | |
613 | pInfo->state = R3964_WAIT_FOR_RX_BUF; | |
614 | mod_timer(&pInfo->tmr, | |
615 | jiffies + R3964_TO_NO_BUF); | |
616 | break; | |
617 | } | |
1da177e4 | 618 | start_receiving: |
5e07e1cc JS |
619 | /* Ok, start receiving: */ |
620 | TRACE_PS("IDLE - got STX"); | |
621 | pInfo->rx_position = 0; | |
622 | pInfo->last_rx = 0; | |
623 | pInfo->flags &= ~R3964_ERROR; | |
624 | pInfo->state = R3964_RECEIVING; | |
625 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
626 | pInfo->nRetry = 0; | |
627 | put_char(pInfo, DLE); | |
628 | flush(pInfo); | |
629 | pInfo->bcc = 0; | |
630 | } | |
631 | break; | |
632 | case R3964_RECEIVING: | |
633 | if (pInfo->rx_position < RX_BUF_SIZE) { | |
634 | pInfo->bcc ^= c; | |
635 | ||
636 | if (c == DLE) { | |
637 | if (pInfo->last_rx == DLE) { | |
638 | pInfo->last_rx = 0; | |
639 | goto char_to_buf; | |
640 | } | |
641 | pInfo->last_rx = DLE; | |
642 | break; | |
643 | } else if ((c == ETX) && (pInfo->last_rx == DLE)) { | |
644 | if (pInfo->flags & R3964_BCC) { | |
645 | pInfo->state = R3964_WAIT_FOR_BCC; | |
646 | mod_timer(&pInfo->tmr, | |
647 | jiffies + R3964_TO_ZVZ); | |
648 | } else { | |
649 | on_receive_block(pInfo); | |
650 | } | |
651 | } else { | |
652 | pInfo->last_rx = c; | |
1da177e4 | 653 | char_to_buf: |
5e07e1cc JS |
654 | pInfo->rx_buf[pInfo->rx_position++] = c; |
655 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
656 | } | |
657 | } | |
658 | /* else: overflow-msg? BUF_SIZE>MTU; should not happen? */ | |
659 | break; | |
660 | case R3964_WAIT_FOR_BCC: | |
661 | pInfo->last_rx = c; | |
662 | on_receive_block(pInfo); | |
663 | break; | |
664 | } | |
1da177e4 LT |
665 | } |
666 | ||
667 | static void receive_error(struct r3964_info *pInfo, const char flag) | |
668 | { | |
5e07e1cc JS |
669 | switch (flag) { |
670 | case TTY_NORMAL: | |
671 | break; | |
672 | case TTY_BREAK: | |
673 | TRACE_PE("received break"); | |
674 | pInfo->flags |= R3964_BREAK; | |
675 | break; | |
676 | case TTY_PARITY: | |
677 | TRACE_PE("parity error"); | |
678 | pInfo->flags |= R3964_PARITY; | |
679 | break; | |
680 | case TTY_FRAME: | |
681 | TRACE_PE("frame error"); | |
682 | pInfo->flags |= R3964_FRAME; | |
683 | break; | |
684 | case TTY_OVERRUN: | |
685 | TRACE_PE("frame overrun"); | |
686 | pInfo->flags |= R3964_OVERRUN; | |
687 | break; | |
688 | default: | |
689 | TRACE_PE("receive_error - unknown flag %d", flag); | |
690 | pInfo->flags |= R3964_UNKNOWN; | |
691 | break; | |
692 | } | |
1da177e4 LT |
693 | } |
694 | ||
695 | static void on_timeout(unsigned long priv) | |
696 | { | |
5e07e1cc JS |
697 | struct r3964_info *pInfo = (void *)priv; |
698 | ||
699 | switch (pInfo->state) { | |
700 | case R3964_TX_REQUEST: | |
701 | TRACE_PE("TX_REQUEST - timeout"); | |
702 | retry_transmit(pInfo); | |
703 | break; | |
704 | case R3964_WAIT_ZVZ_BEFORE_TX_RETRY: | |
705 | put_char(pInfo, NAK); | |
706 | flush(pInfo); | |
707 | retry_transmit(pInfo); | |
708 | break; | |
709 | case R3964_WAIT_FOR_TX_ACK: | |
710 | TRACE_PE("WAIT_FOR_TX_ACK - timeout"); | |
711 | retry_transmit(pInfo); | |
712 | break; | |
713 | case R3964_WAIT_FOR_RX_BUF: | |
714 | TRACE_PE("WAIT_FOR_RX_BUF - timeout"); | |
715 | put_char(pInfo, NAK); | |
716 | flush(pInfo); | |
717 | pInfo->state = R3964_IDLE; | |
718 | break; | |
719 | case R3964_RECEIVING: | |
720 | TRACE_PE("RECEIVING - timeout after %d chars", | |
721 | pInfo->rx_position); | |
722 | put_char(pInfo, NAK); | |
723 | flush(pInfo); | |
724 | pInfo->state = R3964_IDLE; | |
725 | break; | |
726 | case R3964_WAIT_FOR_RX_REPEAT: | |
727 | TRACE_PE("WAIT_FOR_RX_REPEAT - timeout"); | |
728 | pInfo->state = R3964_IDLE; | |
729 | break; | |
730 | case R3964_WAIT_FOR_BCC: | |
731 | TRACE_PE("WAIT_FOR_BCC - timeout"); | |
732 | put_char(pInfo, NAK); | |
733 | flush(pInfo); | |
734 | pInfo->state = R3964_IDLE; | |
735 | break; | |
736 | } | |
1da177e4 LT |
737 | } |
738 | ||
5e07e1cc JS |
739 | static struct r3964_client_info *findClient(struct r3964_info *pInfo, |
740 | struct pid *pid) | |
1da177e4 | 741 | { |
5e07e1cc JS |
742 | struct r3964_client_info *pClient; |
743 | ||
744 | for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { | |
745 | if (pClient->pid == pid) { | |
746 | return pClient; | |
747 | } | |
748 | } | |
749 | return NULL; | |
1da177e4 LT |
750 | } |
751 | ||
3cec556a | 752 | static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg) |
1da177e4 | 753 | { |
5e07e1cc JS |
754 | struct r3964_client_info *pClient; |
755 | struct r3964_client_info **ppClient; | |
756 | struct r3964_message *pMsg; | |
757 | ||
758 | if ((arg & R3964_SIG_ALL) == 0) { | |
759 | /* Remove client from client list */ | |
760 | for (ppClient = &pInfo->firstClient; *ppClient; | |
761 | ppClient = &(*ppClient)->next) { | |
762 | pClient = *ppClient; | |
763 | ||
764 | if (pClient->pid == pid) { | |
765 | TRACE_PS("removing client %d from client list", | |
766 | pid_nr(pid)); | |
767 | *ppClient = pClient->next; | |
768 | while (pClient->msg_count) { | |
769 | pMsg = remove_msg(pInfo, pClient); | |
770 | if (pMsg) { | |
771 | kfree(pMsg); | |
772 | TRACE_M("enable_signals - msg " | |
773 | "kfree %p", pMsg); | |
774 | } | |
775 | } | |
776 | put_pid(pClient->pid); | |
777 | kfree(pClient); | |
778 | TRACE_M("enable_signals - kfree %p", pClient); | |
779 | return 0; | |
780 | } | |
781 | } | |
782 | return -EINVAL; | |
783 | } else { | |
784 | pClient = findClient(pInfo, pid); | |
785 | if (pClient) { | |
786 | /* update signal options */ | |
787 | pClient->sig_flags = arg; | |
788 | } else { | |
789 | /* add client to client list */ | |
790 | pClient = kmalloc(sizeof(struct r3964_client_info), | |
791 | GFP_KERNEL); | |
792 | TRACE_M("enable_signals - kmalloc %p", pClient); | |
793 | if (pClient == NULL) | |
794 | return -ENOMEM; | |
795 | ||
796 | TRACE_PS("add client %d to client list", pid_nr(pid)); | |
797 | spin_lock_init(&pClient->lock); | |
798 | pClient->sig_flags = arg; | |
799 | pClient->pid = get_pid(pid); | |
800 | pClient->next = pInfo->firstClient; | |
801 | pClient->first_msg = NULL; | |
802 | pClient->last_msg = NULL; | |
803 | pClient->next_block_to_read = NULL; | |
804 | pClient->msg_count = 0; | |
805 | pInfo->firstClient = pClient; | |
806 | } | |
807 | } | |
808 | ||
809 | return 0; | |
1da177e4 LT |
810 | } |
811 | ||
5e07e1cc JS |
812 | static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
813 | unsigned char __user * buf) | |
1da177e4 | 814 | { |
5e07e1cc JS |
815 | struct r3964_client_info *pClient; |
816 | struct r3964_block_header *block; | |
817 | ||
818 | if (!buf) { | |
819 | return -EINVAL; | |
820 | } | |
821 | ||
822 | pClient = findClient(pInfo, pid); | |
823 | if (pClient == NULL) { | |
824 | return -EINVAL; | |
825 | } | |
826 | ||
827 | block = pClient->next_block_to_read; | |
828 | if (!block) { | |
829 | return 0; | |
830 | } else { | |
831 | if (copy_to_user(buf, block->data, block->length)) | |
832 | return -EFAULT; | |
833 | ||
834 | remove_client_block(pInfo, pClient); | |
835 | return block->length; | |
836 | } | |
837 | ||
838 | return -EINVAL; | |
1da177e4 LT |
839 | } |
840 | ||
841 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, | |
5e07e1cc | 842 | int error_code, struct r3964_block_header *pBlock) |
1da177e4 | 843 | { |
5e07e1cc JS |
844 | struct r3964_message *pMsg; |
845 | unsigned long flags; | |
846 | ||
847 | if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) { | |
1da177e4 LT |
848 | queue_the_message: |
849 | ||
5e07e1cc JS |
850 | pMsg = kmalloc(sizeof(struct r3964_message), |
851 | error_code ? GFP_ATOMIC : GFP_KERNEL); | |
852 | TRACE_M("add_msg - kmalloc %p", pMsg); | |
853 | if (pMsg == NULL) { | |
854 | return; | |
855 | } | |
856 | ||
857 | spin_lock_irqsave(&pClient->lock, flags); | |
858 | ||
859 | pMsg->msg_id = msg_id; | |
860 | pMsg->arg = arg; | |
861 | pMsg->error_code = error_code; | |
862 | pMsg->block = pBlock; | |
863 | pMsg->next = NULL; | |
864 | ||
865 | if (pClient->last_msg == NULL) { | |
866 | pClient->first_msg = pClient->last_msg = pMsg; | |
867 | } else { | |
868 | pClient->last_msg->next = pMsg; | |
869 | pClient->last_msg = pMsg; | |
870 | } | |
871 | ||
872 | pClient->msg_count++; | |
873 | ||
874 | if (pBlock != NULL) { | |
875 | pBlock->locks++; | |
876 | } | |
877 | spin_unlock_irqrestore(&pClient->lock, flags); | |
878 | } else { | |
879 | if ((pClient->last_msg->msg_id == R3964_MSG_ACK) | |
880 | && (pClient->last_msg->error_code == R3964_OVERFLOW)) { | |
881 | pClient->last_msg->arg++; | |
882 | TRACE_PE("add_msg - inc prev OVERFLOW-msg"); | |
883 | } else { | |
884 | msg_id = R3964_MSG_ACK; | |
885 | arg = 0; | |
886 | error_code = R3964_OVERFLOW; | |
887 | pBlock = NULL; | |
888 | TRACE_PE("add_msg - queue OVERFLOW-msg"); | |
889 | goto queue_the_message; | |
890 | } | |
891 | } | |
892 | /* Send SIGIO signal to client process: */ | |
893 | if (pClient->sig_flags & R3964_USE_SIGIO) { | |
894 | kill_pid(pClient->pid, SIGIO, 1); | |
895 | } | |
1da177e4 LT |
896 | } |
897 | ||
898 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, | |
5e07e1cc | 899 | struct r3964_client_info *pClient) |
1da177e4 | 900 | { |
5e07e1cc JS |
901 | struct r3964_message *pMsg = NULL; |
902 | unsigned long flags; | |
903 | ||
904 | if (pClient->first_msg) { | |
905 | spin_lock_irqsave(&pClient->lock, flags); | |
906 | ||
907 | pMsg = pClient->first_msg; | |
908 | pClient->first_msg = pMsg->next; | |
909 | if (pClient->first_msg == NULL) { | |
910 | pClient->last_msg = NULL; | |
911 | } | |
912 | ||
913 | pClient->msg_count--; | |
914 | if (pMsg->block) { | |
915 | remove_client_block(pInfo, pClient); | |
916 | pClient->next_block_to_read = pMsg->block; | |
917 | } | |
918 | spin_unlock_irqrestore(&pClient->lock, flags); | |
919 | } | |
920 | return pMsg; | |
1da177e4 LT |
921 | } |
922 | ||
5e07e1cc JS |
923 | static void remove_client_block(struct r3964_info *pInfo, |
924 | struct r3964_client_info *pClient) | |
1da177e4 | 925 | { |
5e07e1cc JS |
926 | struct r3964_block_header *block; |
927 | ||
928 | TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid)); | |
1da177e4 | 929 | |
5e07e1cc JS |
930 | block = pClient->next_block_to_read; |
931 | if (block) { | |
932 | block->locks--; | |
933 | if (block->locks == 0) { | |
934 | remove_from_rx_queue(pInfo, block); | |
935 | } | |
936 | } | |
937 | pClient->next_block_to_read = NULL; | |
938 | } | |
1da177e4 LT |
939 | |
940 | /************************************************************* | |
941 | * Line discipline routines | |
942 | *************************************************************/ | |
943 | ||
944 | static int r3964_open(struct tty_struct *tty) | |
945 | { | |
5e07e1cc JS |
946 | struct r3964_info *pInfo; |
947 | ||
948 | TRACE_L("open"); | |
949 | TRACE_L("tty=%p, PID=%d, disc_data=%p", | |
950 | tty, current->pid, tty->disc_data); | |
951 | ||
952 | pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL); | |
953 | TRACE_M("r3964_open - info kmalloc %p", pInfo); | |
954 | ||
955 | if (!pInfo) { | |
956 | printk(KERN_ERR "r3964: failed to alloc info structure\n"); | |
957 | return -ENOMEM; | |
958 | } | |
959 | ||
960 | pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL); | |
961 | TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf); | |
962 | ||
963 | if (!pInfo->rx_buf) { | |
964 | printk(KERN_ERR "r3964: failed to alloc receive buffer\n"); | |
965 | kfree(pInfo); | |
966 | TRACE_M("r3964_open - info kfree %p", pInfo); | |
967 | return -ENOMEM; | |
968 | } | |
969 | ||
970 | pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL); | |
971 | TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf); | |
972 | ||
973 | if (!pInfo->tx_buf) { | |
974 | printk(KERN_ERR "r3964: failed to alloc transmit buffer\n"); | |
975 | kfree(pInfo->rx_buf); | |
976 | TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf); | |
977 | kfree(pInfo); | |
978 | TRACE_M("r3964_open - info kfree %p", pInfo); | |
979 | return -ENOMEM; | |
980 | } | |
981 | ||
982 | spin_lock_init(&pInfo->lock); | |
983 | pInfo->tty = tty; | |
984 | init_waitqueue_head(&pInfo->read_wait); | |
985 | pInfo->priority = R3964_MASTER; | |
986 | pInfo->rx_first = pInfo->rx_last = NULL; | |
987 | pInfo->tx_first = pInfo->tx_last = NULL; | |
988 | pInfo->rx_position = 0; | |
989 | pInfo->tx_position = 0; | |
990 | pInfo->last_rx = 0; | |
991 | pInfo->blocks_in_rx_queue = 0; | |
992 | pInfo->firstClient = NULL; | |
993 | pInfo->state = R3964_IDLE; | |
994 | pInfo->flags = R3964_DEBUG; | |
995 | pInfo->nRetry = 0; | |
996 | ||
997 | tty->disc_data = pInfo; | |
998 | tty->receive_room = 65536; | |
999 | ||
40565f19 | 1000 | setup_timer(&pInfo->tmr, on_timeout, (unsigned long)pInfo); |
5e07e1cc JS |
1001 | |
1002 | return 0; | |
1da177e4 LT |
1003 | } |
1004 | ||
1005 | static void r3964_close(struct tty_struct *tty) | |
1006 | { | |
c9f19e96 | 1007 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1008 | struct r3964_client_info *pClient, *pNext; |
1009 | struct r3964_message *pMsg; | |
1010 | struct r3964_block_header *pHeader, *pNextHeader; | |
1011 | unsigned long flags; | |
1012 | ||
1013 | TRACE_L("close"); | |
1014 | ||
1015 | /* | |
1016 | * Make sure that our task queue isn't activated. If it | |
1017 | * is, take it out of the linked list. | |
1018 | */ | |
1019 | del_timer_sync(&pInfo->tmr); | |
1020 | ||
1021 | /* Remove client-structs and message queues: */ | |
1022 | pClient = pInfo->firstClient; | |
1023 | while (pClient) { | |
1024 | pNext = pClient->next; | |
1025 | while (pClient->msg_count) { | |
1026 | pMsg = remove_msg(pInfo, pClient); | |
1027 | if (pMsg) { | |
1028 | kfree(pMsg); | |
1029 | TRACE_M("r3964_close - msg kfree %p", pMsg); | |
1030 | } | |
1031 | } | |
1032 | put_pid(pClient->pid); | |
1033 | kfree(pClient); | |
1034 | TRACE_M("r3964_close - client kfree %p", pClient); | |
1035 | pClient = pNext; | |
1036 | } | |
1037 | /* Remove jobs from tx_queue: */ | |
1038 | spin_lock_irqsave(&pInfo->lock, flags); | |
1039 | pHeader = pInfo->tx_first; | |
1040 | pInfo->tx_first = pInfo->tx_last = NULL; | |
1da177e4 | 1041 | spin_unlock_irqrestore(&pInfo->lock, flags); |
5e07e1cc JS |
1042 | |
1043 | while (pHeader) { | |
1044 | pNextHeader = pHeader->next; | |
1045 | kfree(pHeader); | |
1046 | pHeader = pNextHeader; | |
1da177e4 LT |
1047 | } |
1048 | ||
5e07e1cc JS |
1049 | /* Free buffers: */ |
1050 | wake_up_interruptible(&pInfo->read_wait); | |
1051 | kfree(pInfo->rx_buf); | |
1052 | TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf); | |
1053 | kfree(pInfo->tx_buf); | |
1054 | TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf); | |
1055 | kfree(pInfo); | |
1056 | TRACE_M("r3964_close - info kfree %p", pInfo); | |
1da177e4 LT |
1057 | } |
1058 | ||
1059 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, | |
5e07e1cc | 1060 | unsigned char __user * buf, size_t nr) |
1da177e4 | 1061 | { |
c9f19e96 | 1062 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1063 | struct r3964_client_info *pClient; |
1064 | struct r3964_message *pMsg; | |
1065 | struct r3964_client_message theMsg; | |
eca41044 | 1066 | int ret; |
5e07e1cc JS |
1067 | |
1068 | TRACE_L("read()"); | |
1069 | ||
04f378b1 AC |
1070 | lock_kernel(); |
1071 | ||
5e07e1cc JS |
1072 | pClient = findClient(pInfo, task_pid(current)); |
1073 | if (pClient) { | |
1074 | pMsg = remove_msg(pInfo, pClient); | |
1075 | if (pMsg == NULL) { | |
1076 | /* no messages available. */ | |
1077 | if (file->f_flags & O_NONBLOCK) { | |
eca41044 JS |
1078 | ret = -EAGAIN; |
1079 | goto unlock; | |
5e07e1cc JS |
1080 | } |
1081 | /* block until there is a message: */ | |
6defec13 JS |
1082 | wait_event_interruptible(pInfo->read_wait, |
1083 | (pMsg = remove_msg(pInfo, pClient))); | |
5e07e1cc JS |
1084 | } |
1085 | ||
1086 | /* If we still haven't got a message, we must have been signalled */ | |
1087 | ||
04f378b1 | 1088 | if (!pMsg) { |
eca41044 JS |
1089 | ret = -EINTR; |
1090 | goto unlock; | |
04f378b1 | 1091 | } |
5e07e1cc JS |
1092 | |
1093 | /* deliver msg to client process: */ | |
1094 | theMsg.msg_id = pMsg->msg_id; | |
1095 | theMsg.arg = pMsg->arg; | |
1096 | theMsg.error_code = pMsg->error_code; | |
eca41044 | 1097 | ret = sizeof(struct r3964_client_message); |
5e07e1cc JS |
1098 | |
1099 | kfree(pMsg); | |
1100 | TRACE_M("r3964_read - msg kfree %p", pMsg); | |
1101 | ||
eca41044 JS |
1102 | if (copy_to_user(buf, &theMsg, ret)) { |
1103 | ret = -EFAULT; | |
1104 | goto unlock; | |
04f378b1 | 1105 | } |
5e07e1cc | 1106 | |
eca41044 JS |
1107 | TRACE_PS("read - return %d", ret); |
1108 | goto unlock; | |
5e07e1cc | 1109 | } |
eca41044 JS |
1110 | ret = -EPERM; |
1111 | unlock: | |
04f378b1 | 1112 | unlock_kernel(); |
eca41044 | 1113 | return ret; |
1da177e4 LT |
1114 | } |
1115 | ||
5e07e1cc | 1116 | static ssize_t r3964_write(struct tty_struct *tty, struct file *file, |
1da177e4 LT |
1117 | const unsigned char *data, size_t count) |
1118 | { | |
c9f19e96 | 1119 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1120 | struct r3964_block_header *pHeader; |
1121 | struct r3964_client_info *pClient; | |
1122 | unsigned char *new_data; | |
1123 | ||
1124 | TRACE_L("write request, %d characters", count); | |
1da177e4 LT |
1125 | /* |
1126 | * Verify the pointers | |
1127 | */ | |
1128 | ||
5e07e1cc JS |
1129 | if (!pInfo) |
1130 | return -EIO; | |
1da177e4 LT |
1131 | |
1132 | /* | |
1133 | * Ensure that the caller does not wish to send too much. | |
1134 | */ | |
5e07e1cc JS |
1135 | if (count > R3964_MTU) { |
1136 | if (pInfo->flags & R3964_DEBUG) { | |
1137 | TRACE_L(KERN_WARNING "r3964_write: truncating user " | |
1138 | "packet from %u to mtu %d", count, R3964_MTU); | |
1139 | } | |
1140 | count = R3964_MTU; | |
1141 | } | |
1da177e4 LT |
1142 | /* |
1143 | * Allocate a buffer for the data and copy it from the buffer with header prepended | |
1144 | */ | |
5e07e1cc JS |
1145 | new_data = kmalloc(count + sizeof(struct r3964_block_header), |
1146 | GFP_KERNEL); | |
1147 | TRACE_M("r3964_write - kmalloc %p", new_data); | |
1148 | if (new_data == NULL) { | |
1149 | if (pInfo->flags & R3964_DEBUG) { | |
1150 | printk(KERN_ERR "r3964_write: no memory\n"); | |
1151 | } | |
1152 | return -ENOSPC; | |
1153 | } | |
1154 | ||
1155 | pHeader = (struct r3964_block_header *)new_data; | |
1156 | pHeader->data = new_data + sizeof(struct r3964_block_header); | |
1157 | pHeader->length = count; | |
1158 | pHeader->locks = 0; | |
1159 | pHeader->owner = NULL; | |
1160 | ||
04f378b1 AC |
1161 | lock_kernel(); |
1162 | ||
5e07e1cc JS |
1163 | pClient = findClient(pInfo, task_pid(current)); |
1164 | if (pClient) { | |
1165 | pHeader->owner = pClient; | |
1166 | } | |
1167 | ||
1168 | memcpy(pHeader->data, data, count); /* We already verified this */ | |
1169 | ||
1170 | if (pInfo->flags & R3964_DEBUG) { | |
1171 | dump_block(pHeader->data, count); | |
1172 | } | |
1da177e4 LT |
1173 | |
1174 | /* | |
1175 | * Add buffer to transmit-queue: | |
1176 | */ | |
5e07e1cc JS |
1177 | add_tx_queue(pInfo, pHeader); |
1178 | trigger_transmit(pInfo); | |
1179 | ||
04f378b1 AC |
1180 | unlock_kernel(); |
1181 | ||
5e07e1cc | 1182 | return 0; |
1da177e4 LT |
1183 | } |
1184 | ||
5e07e1cc JS |
1185 | static int r3964_ioctl(struct tty_struct *tty, struct file *file, |
1186 | unsigned int cmd, unsigned long arg) | |
1da177e4 | 1187 | { |
c9f19e96 | 1188 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1189 | if (pInfo == NULL) |
1190 | return -EINVAL; | |
1191 | switch (cmd) { | |
1192 | case R3964_ENABLE_SIGNALS: | |
1193 | return enable_signals(pInfo, task_pid(current), arg); | |
1194 | case R3964_SETPRIORITY: | |
1195 | if (arg < R3964_MASTER || arg > R3964_SLAVE) | |
1196 | return -EINVAL; | |
1197 | pInfo->priority = arg & 0xff; | |
1198 | return 0; | |
1199 | case R3964_USE_BCC: | |
1200 | if (arg) | |
1201 | pInfo->flags |= R3964_BCC; | |
1202 | else | |
1203 | pInfo->flags &= ~R3964_BCC; | |
1204 | return 0; | |
1205 | case R3964_READ_TELEGRAM: | |
1206 | return read_telegram(pInfo, task_pid(current), | |
1207 | (unsigned char __user *)arg); | |
1208 | default: | |
1209 | return -ENOIOCTLCMD; | |
1210 | } | |
1da177e4 LT |
1211 | } |
1212 | ||
5e07e1cc | 1213 | static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old) |
1da177e4 | 1214 | { |
5e07e1cc | 1215 | TRACE_L("set_termios"); |
1da177e4 LT |
1216 | } |
1217 | ||
1218 | /* Called without the kernel lock held - fine */ | |
5e07e1cc JS |
1219 | static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, |
1220 | struct poll_table_struct *wait) | |
1da177e4 | 1221 | { |
c9f19e96 | 1222 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1223 | struct r3964_client_info *pClient; |
1224 | struct r3964_message *pMsg = NULL; | |
1225 | unsigned long flags; | |
1226 | int result = POLLOUT; | |
1227 | ||
1228 | TRACE_L("POLL"); | |
1229 | ||
1230 | pClient = findClient(pInfo, task_pid(current)); | |
1231 | if (pClient) { | |
1232 | poll_wait(file, &pInfo->read_wait, wait); | |
1233 | spin_lock_irqsave(&pInfo->lock, flags); | |
1234 | pMsg = pClient->first_msg; | |
1235 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
1236 | if (pMsg) | |
1237 | result |= POLLIN | POLLRDNORM; | |
1238 | } else { | |
1239 | result = -EINVAL; | |
1240 | } | |
1241 | return result; | |
1da177e4 LT |
1242 | } |
1243 | ||
1244 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, | |
5e07e1cc | 1245 | char *fp, int count) |
1da177e4 | 1246 | { |
c9f19e96 | 1247 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1248 | const unsigned char *p; |
1249 | char *f, flags = 0; | |
1250 | int i; | |
1251 | ||
1252 | for (i = count, p = cp, f = fp; i; i--, p++) { | |
1253 | if (f) | |
1254 | flags = *f++; | |
1255 | if (flags == TTY_NORMAL) { | |
1256 | receive_char(pInfo, *p); | |
1257 | } else { | |
1258 | receive_error(pInfo, flags); | |
1259 | } | |
1260 | ||
1261 | } | |
1da177e4 LT |
1262 | } |
1263 | ||
1da177e4 LT |
1264 | MODULE_LICENSE("GPL"); |
1265 | MODULE_ALIAS_LDISC(N_R3964); |