Commit | Line | Data |
---|---|---|
e3b3d0f5 | 1 | // SPDX-License-Identifier: GPL-1.0+ |
1da177e4 LT |
2 | /* r3964 linediscipline for linux |
3 | * | |
4 | * ----------------------------------------------------------- | |
5 | * Copyright by | |
6 | * Philips Automation Projects | |
7 | * Kassel (Germany) | |
1da177e4 | 8 | * ----------------------------------------------------------- |
1da177e4 LT |
9 | * Author: |
10 | * L. Haag | |
11 | * | |
12 | * $Log: n_r3964.c,v $ | |
13 | * Revision 1.10 2001/03/18 13:02:24 dwmw2 | |
14 | * Fix timer usage, use spinlocks properly. | |
15 | * | |
16 | * Revision 1.9 2001/03/18 12:52:14 dwmw2 | |
17 | * Merge changes in 2.4.2 | |
18 | * | |
19 | * Revision 1.8 2000/03/23 14:14:54 dwmw2 | |
20 | * Fix race in sleeping in r3964_read() | |
21 | * | |
22 | * Revision 1.7 1999/28/08 11:41:50 dwmw2 | |
23 | * Port to 2.3 kernel | |
24 | * | |
25 | * Revision 1.6 1998/09/30 00:40:40 dwmw2 | |
26 | * Fixed compilation on 2.0.x kernels | |
27 | * Updated to newly registered tty-ldisc number 9 | |
28 | * | |
29 | * Revision 1.5 1998/09/04 21:57:36 dwmw2 | |
30 | * Signal handling bug fixes, port to 2.1.x. | |
31 | * | |
32 | * Revision 1.4 1998/04/02 20:26:59 lhaag | |
33 | * select, blocking, ... | |
34 | * | |
35 | * Revision 1.3 1998/02/12 18:58:43 root | |
36 | * fixed some memory leaks | |
37 | * calculation of checksum characters | |
38 | * | |
39 | * Revision 1.2 1998/02/07 13:03:34 root | |
40 | * ioctl read_telegram | |
41 | * | |
42 | * Revision 1.1 1998/02/06 19:21:03 root | |
43 | * Initial revision | |
44 | * | |
45 | * | |
46 | */ | |
47 | ||
48 | #include <linux/module.h> | |
49 | #include <linux/kernel.h> | |
50 | #include <linux/sched.h> | |
51 | #include <linux/types.h> | |
52 | #include <linux/fcntl.h> | |
53 | #include <linux/interrupt.h> | |
54 | #include <linux/ptrace.h> | |
55 | #include <linux/ioport.h> | |
56 | #include <linux/in.h> | |
57 | #include <linux/slab.h> | |
58 | #include <linux/tty.h> | |
59 | #include <linux/errno.h> | |
5e07e1cc JS |
60 | #include <linux/string.h> /* used in new tty drivers */ |
61 | #include <linux/signal.h> /* used in new tty drivers */ | |
1da177e4 LT |
62 | #include <linux/ioctl.h> |
63 | #include <linux/n_r3964.h> | |
64 | #include <linux/poll.h> | |
65 | #include <linux/init.h> | |
7c0f6ba6 | 66 | #include <linux/uaccess.h> |
1da177e4 | 67 | |
5e07e1cc | 68 | /*#define DEBUG_QUEUE*/ |
1da177e4 LT |
69 | |
70 | /* Log successful handshake and protocol operations */ | |
5e07e1cc | 71 | /*#define DEBUG_PROTO_S*/ |
1da177e4 LT |
72 | |
73 | /* Log handshake and protocol errors: */ | |
5e07e1cc | 74 | /*#define DEBUG_PROTO_E*/ |
1da177e4 LT |
75 | |
76 | /* Log Linediscipline operations (open, close, read, write...): */ | |
5e07e1cc | 77 | /*#define DEBUG_LDISC*/ |
1da177e4 LT |
78 | |
79 | /* Log module and memory operations (init, cleanup; kmalloc, kfree): */ | |
5e07e1cc | 80 | /*#define DEBUG_MODUL*/ |
1da177e4 LT |
81 | |
82 | /* Macro helpers for debug output: */ | |
5e07e1cc | 83 | #define TRACE(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 LT |
84 | |
85 | #ifdef DEBUG_MODUL | |
5e07e1cc | 86 | #define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 87 | #else |
5e07e1cc | 88 | #define TRACE_M(fmt, arg...) do {} while (0) |
1da177e4 | 89 | #endif |
1da177e4 | 90 | #ifdef DEBUG_PROTO_S |
5e07e1cc | 91 | #define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 92 | #else |
5e07e1cc | 93 | #define TRACE_PS(fmt, arg...) do {} while (0) |
1da177e4 | 94 | #endif |
1da177e4 | 95 | #ifdef DEBUG_PROTO_E |
5e07e1cc | 96 | #define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 97 | #else |
5e07e1cc | 98 | #define TRACE_PE(fmt, arg...) do {} while (0) |
1da177e4 | 99 | #endif |
1da177e4 | 100 | #ifdef DEBUG_LDISC |
5e07e1cc | 101 | #define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 102 | #else |
5e07e1cc | 103 | #define TRACE_L(fmt, arg...) do {} while (0) |
1da177e4 | 104 | #endif |
1da177e4 | 105 | #ifdef DEBUG_QUEUE |
5e07e1cc | 106 | #define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args) |
1da177e4 | 107 | #else |
5e07e1cc | 108 | #define TRACE_Q(fmt, arg...) do {} while (0) |
1da177e4 | 109 | #endif |
1da177e4 LT |
110 | static void add_tx_queue(struct r3964_info *, struct r3964_block_header *); |
111 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code); | |
112 | static void put_char(struct r3964_info *pInfo, unsigned char ch); | |
113 | static void trigger_transmit(struct r3964_info *pInfo); | |
114 | static void retry_transmit(struct r3964_info *pInfo); | |
115 | static void transmit_block(struct r3964_info *pInfo); | |
116 | static void receive_char(struct r3964_info *pInfo, const unsigned char c); | |
117 | static void receive_error(struct r3964_info *pInfo, const char flag); | |
e99e88a9 | 118 | static void on_timeout(struct timer_list *t); |
3cec556a | 119 | static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg); |
5e07e1cc JS |
120 | static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
121 | unsigned char __user * buf); | |
1da177e4 | 122 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
5e07e1cc JS |
123 | int error_code, struct r3964_block_header *pBlock); |
124 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, | |
125 | struct r3964_client_info *pClient); | |
126 | static void remove_client_block(struct r3964_info *pInfo, | |
127 | struct r3964_client_info *pClient); | |
1da177e4 | 128 | |
5e07e1cc | 129 | static int r3964_open(struct tty_struct *tty); |
1da177e4 LT |
130 | static void r3964_close(struct tty_struct *tty); |
131 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, | |
5e07e1cc JS |
132 | unsigned char __user * buf, size_t nr); |
133 | static ssize_t r3964_write(struct tty_struct *tty, struct file *file, | |
134 | const unsigned char *buf, size_t nr); | |
135 | static int r3964_ioctl(struct tty_struct *tty, struct file *file, | |
136 | unsigned int cmd, unsigned long arg); | |
f0193d3e AV |
137 | #ifdef CONFIG_COMPAT |
138 | static int r3964_compat_ioctl(struct tty_struct *tty, struct file *file, | |
139 | unsigned int cmd, unsigned long arg); | |
140 | #endif | |
5e07e1cc | 141 | static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old); |
afc9a42b | 142 | static __poll_t r3964_poll(struct tty_struct *tty, struct file *file, |
5e07e1cc | 143 | struct poll_table_struct *wait); |
55db4c64 LT |
144 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
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, | |
f0193d3e AV |
156 | #ifdef CONFIG_COMPAT |
157 | .compat_ioctl = r3964_compat_ioctl, | |
158 | #endif | |
1da177e4 | 159 | .set_termios = r3964_set_termios, |
5e07e1cc | 160 | .poll = r3964_poll, |
1da177e4 | 161 | .receive_buf = r3964_receive_buf, |
1da177e4 LT |
162 | }; |
163 | ||
1da177e4 LT |
164 | static void dump_block(const unsigned char *block, unsigned int length) |
165 | { | |
5e07e1cc JS |
166 | unsigned int i, j; |
167 | char linebuf[16 * 3 + 1]; | |
168 | ||
169 | for (i = 0; i < length; i += 16) { | |
170 | for (j = 0; (j < 16) && (j + i < length); j++) { | |
171 | sprintf(linebuf + 3 * j, "%02x ", block[i + j]); | |
172 | } | |
173 | linebuf[3 * j] = '\0'; | |
174 | TRACE_PS("%s", linebuf); | |
175 | } | |
1da177e4 LT |
176 | } |
177 | ||
1da177e4 LT |
178 | /************************************************************* |
179 | * Driver initialisation | |
180 | *************************************************************/ | |
181 | ||
1da177e4 LT |
182 | /************************************************************* |
183 | * Module support routines | |
184 | *************************************************************/ | |
185 | ||
186 | static void __exit r3964_exit(void) | |
187 | { | |
5e07e1cc JS |
188 | int status; |
189 | ||
190 | TRACE_M("cleanup_module()"); | |
191 | ||
192 | status = tty_unregister_ldisc(N_R3964); | |
193 | ||
194 | if (status != 0) { | |
195 | printk(KERN_ERR "r3964: error unregistering linediscipline: " | |
196 | "%d\n", status); | |
197 | } else { | |
198 | TRACE_L("linediscipline successfully unregistered"); | |
199 | } | |
1da177e4 LT |
200 | } |
201 | ||
202 | static int __init r3964_init(void) | |
203 | { | |
5e07e1cc JS |
204 | int status; |
205 | ||
206 | printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n"); | |
207 | ||
208 | /* | |
209 | * Register the tty line discipline | |
210 | */ | |
211 | ||
212 | status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964); | |
213 | if (status == 0) { | |
214 | TRACE_L("line discipline %d registered", N_R3964); | |
215 | TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags, | |
216 | tty_ldisc_N_R3964.num); | |
217 | TRACE_L("open=%p", tty_ldisc_N_R3964.open); | |
218 | TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964); | |
219 | } else { | |
220 | printk(KERN_ERR "r3964: error registering line discipline: " | |
221 | "%d\n", status); | |
222 | } | |
223 | return status; | |
1da177e4 LT |
224 | } |
225 | ||
226 | module_init(r3964_init); | |
227 | module_exit(r3964_exit); | |
228 | ||
1da177e4 LT |
229 | /************************************************************* |
230 | * Protocol implementation routines | |
231 | *************************************************************/ | |
232 | ||
5e07e1cc JS |
233 | static void add_tx_queue(struct r3964_info *pInfo, |
234 | struct r3964_block_header *pHeader) | |
1da177e4 | 235 | { |
5e07e1cc JS |
236 | unsigned long flags; |
237 | ||
238 | spin_lock_irqsave(&pInfo->lock, flags); | |
239 | ||
240 | pHeader->next = NULL; | |
241 | ||
242 | if (pInfo->tx_last == NULL) { | |
243 | pInfo->tx_first = pInfo->tx_last = pHeader; | |
244 | } else { | |
245 | pInfo->tx_last->next = pHeader; | |
246 | pInfo->tx_last = pHeader; | |
247 | } | |
248 | ||
249 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
250 | ||
251 | TRACE_Q("add_tx_queue %p, length %d, tx_first = %p", | |
252 | pHeader, pHeader->length, pInfo->tx_first); | |
1da177e4 LT |
253 | } |
254 | ||
255 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code) | |
256 | { | |
5e07e1cc JS |
257 | struct r3964_block_header *pHeader; |
258 | unsigned long flags; | |
1da177e4 | 259 | #ifdef DEBUG_QUEUE |
5e07e1cc | 260 | struct r3964_block_header *pDump; |
1da177e4 | 261 | #endif |
1da177e4 | 262 | |
5e07e1cc JS |
263 | pHeader = pInfo->tx_first; |
264 | ||
265 | if (pHeader == NULL) | |
266 | return; | |
1da177e4 LT |
267 | |
268 | #ifdef DEBUG_QUEUE | |
5e07e1cc JS |
269 | printk("r3964: remove_from_tx_queue: %p, length %u - ", |
270 | pHeader, pHeader->length); | |
271 | for (pDump = pHeader; pDump; pDump = pDump->next) | |
272 | printk("%p ", pDump); | |
273 | printk("\n"); | |
1da177e4 LT |
274 | #endif |
275 | ||
5e07e1cc JS |
276 | if (pHeader->owner) { |
277 | if (error_code) { | |
278 | add_msg(pHeader->owner, R3964_MSG_ACK, 0, | |
279 | error_code, NULL); | |
280 | } else { | |
281 | add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length, | |
282 | error_code, NULL); | |
283 | } | |
9b9ab1b3 | 284 | wake_up_interruptible(&pInfo->tty->read_wait); |
5e07e1cc JS |
285 | } |
286 | ||
287 | spin_lock_irqsave(&pInfo->lock, flags); | |
288 | ||
289 | pInfo->tx_first = pHeader->next; | |
290 | if (pInfo->tx_first == NULL) { | |
291 | pInfo->tx_last = NULL; | |
292 | } | |
293 | ||
294 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
295 | ||
296 | kfree(pHeader); | |
297 | TRACE_M("remove_from_tx_queue - kfree %p", pHeader); | |
1da177e4 | 298 | |
5e07e1cc JS |
299 | TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p", |
300 | pInfo->tx_first, pInfo->tx_last); | |
1da177e4 LT |
301 | } |
302 | ||
5e07e1cc JS |
303 | static void add_rx_queue(struct r3964_info *pInfo, |
304 | struct r3964_block_header *pHeader) | |
1da177e4 | 305 | { |
5e07e1cc JS |
306 | unsigned long flags; |
307 | ||
308 | spin_lock_irqsave(&pInfo->lock, flags); | |
309 | ||
310 | pHeader->next = NULL; | |
311 | ||
312 | if (pInfo->rx_last == NULL) { | |
313 | pInfo->rx_first = pInfo->rx_last = pHeader; | |
314 | } else { | |
315 | pInfo->rx_last->next = pHeader; | |
316 | pInfo->rx_last = pHeader; | |
317 | } | |
318 | pInfo->blocks_in_rx_queue++; | |
319 | ||
320 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
321 | ||
322 | TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d", | |
323 | pHeader, pHeader->length, | |
324 | pInfo->rx_first, pInfo->blocks_in_rx_queue); | |
1da177e4 LT |
325 | } |
326 | ||
327 | static void remove_from_rx_queue(struct r3964_info *pInfo, | |
5e07e1cc | 328 | struct r3964_block_header *pHeader) |
1da177e4 | 329 | { |
5e07e1cc JS |
330 | unsigned long flags; |
331 | struct r3964_block_header *pFind; | |
332 | ||
333 | if (pHeader == NULL) | |
334 | return; | |
335 | ||
336 | TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", | |
337 | pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); | |
338 | TRACE_Q("remove_from_rx_queue: %p, length %u", | |
339 | pHeader, pHeader->length); | |
340 | ||
341 | spin_lock_irqsave(&pInfo->lock, flags); | |
342 | ||
343 | if (pInfo->rx_first == pHeader) { | |
344 | /* Remove the first block in the linked list: */ | |
345 | pInfo->rx_first = pHeader->next; | |
346 | ||
347 | if (pInfo->rx_first == NULL) { | |
348 | pInfo->rx_last = NULL; | |
349 | } | |
350 | pInfo->blocks_in_rx_queue--; | |
351 | } else { | |
352 | /* Find block to remove: */ | |
353 | for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) { | |
354 | if (pFind->next == pHeader) { | |
355 | /* Got it. */ | |
356 | pFind->next = pHeader->next; | |
357 | pInfo->blocks_in_rx_queue--; | |
358 | if (pFind->next == NULL) { | |
359 | /* Oh, removed the last one! */ | |
360 | pInfo->rx_last = pFind; | |
361 | } | |
362 | break; | |
363 | } | |
364 | } | |
365 | } | |
366 | ||
367 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
368 | ||
369 | kfree(pHeader); | |
370 | TRACE_M("remove_from_rx_queue - kfree %p", pHeader); | |
371 | ||
372 | TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", | |
373 | pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); | |
1da177e4 LT |
374 | } |
375 | ||
376 | static void put_char(struct r3964_info *pInfo, unsigned char ch) | |
377 | { | |
5e07e1cc | 378 | struct tty_struct *tty = pInfo->tty; |
f34d7a5b | 379 | /* FIXME: put_char should not be called from an IRQ */ |
51383f69 | 380 | tty_put_char(tty, ch); |
5e07e1cc | 381 | pInfo->bcc ^= ch; |
1da177e4 LT |
382 | } |
383 | ||
384 | static void flush(struct r3964_info *pInfo) | |
385 | { | |
5e07e1cc | 386 | struct tty_struct *tty = pInfo->tty; |
1da177e4 | 387 | |
f34d7a5b | 388 | if (tty == NULL || tty->ops->flush_chars == NULL) |
5e07e1cc | 389 | return; |
f34d7a5b | 390 | tty->ops->flush_chars(tty); |
1da177e4 LT |
391 | } |
392 | ||
393 | static void trigger_transmit(struct r3964_info *pInfo) | |
394 | { | |
5e07e1cc | 395 | unsigned long flags; |
1da177e4 | 396 | |
5e07e1cc | 397 | spin_lock_irqsave(&pInfo->lock, flags); |
1da177e4 | 398 | |
5e07e1cc JS |
399 | if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) { |
400 | pInfo->state = R3964_TX_REQUEST; | |
401 | pInfo->nRetry = 0; | |
402 | pInfo->flags &= ~R3964_ERROR; | |
403 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
1da177e4 | 404 | |
5e07e1cc | 405 | spin_unlock_irqrestore(&pInfo->lock, flags); |
1da177e4 | 406 | |
5e07e1cc | 407 | TRACE_PS("trigger_transmit - sent STX"); |
1da177e4 | 408 | |
5e07e1cc JS |
409 | put_char(pInfo, STX); |
410 | flush(pInfo); | |
1da177e4 | 411 | |
5e07e1cc JS |
412 | pInfo->bcc = 0; |
413 | } else { | |
414 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
415 | } | |
1da177e4 LT |
416 | } |
417 | ||
418 | static void retry_transmit(struct r3964_info *pInfo) | |
419 | { | |
5e07e1cc JS |
420 | if (pInfo->nRetry < R3964_MAX_RETRIES) { |
421 | TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry); | |
422 | pInfo->bcc = 0; | |
423 | put_char(pInfo, STX); | |
424 | flush(pInfo); | |
425 | pInfo->state = R3964_TX_REQUEST; | |
426 | pInfo->nRetry++; | |
427 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
428 | } else { | |
429 | TRACE_PE("transmission failed after %d retries", | |
430 | R3964_MAX_RETRIES); | |
431 | ||
432 | remove_from_tx_queue(pInfo, R3964_TX_FAIL); | |
433 | ||
434 | put_char(pInfo, NAK); | |
435 | flush(pInfo); | |
436 | pInfo->state = R3964_IDLE; | |
437 | ||
438 | trigger_transmit(pInfo); | |
439 | } | |
1da177e4 LT |
440 | } |
441 | ||
1da177e4 LT |
442 | static void transmit_block(struct r3964_info *pInfo) |
443 | { | |
5e07e1cc JS |
444 | struct tty_struct *tty = pInfo->tty; |
445 | struct r3964_block_header *pBlock = pInfo->tx_first; | |
446 | int room = 0; | |
447 | ||
f34d7a5b | 448 | if (tty == NULL || pBlock == NULL) { |
5e07e1cc JS |
449 | return; |
450 | } | |
451 | ||
f34d7a5b | 452 | room = tty_write_room(tty); |
5e07e1cc JS |
453 | |
454 | TRACE_PS("transmit_block %p, room %d, length %d", | |
455 | pBlock, room, pBlock->length); | |
456 | ||
457 | while (pInfo->tx_position < pBlock->length) { | |
458 | if (room < 2) | |
459 | break; | |
460 | ||
461 | if (pBlock->data[pInfo->tx_position] == DLE) { | |
462 | /* send additional DLE char: */ | |
463 | put_char(pInfo, DLE); | |
464 | } | |
465 | put_char(pInfo, pBlock->data[pInfo->tx_position++]); | |
466 | ||
467 | room--; | |
468 | } | |
469 | ||
470 | if ((pInfo->tx_position == pBlock->length) && (room >= 3)) { | |
471 | put_char(pInfo, DLE); | |
472 | put_char(pInfo, ETX); | |
473 | if (pInfo->flags & R3964_BCC) { | |
474 | put_char(pInfo, pInfo->bcc); | |
475 | } | |
476 | pInfo->state = R3964_WAIT_FOR_TX_ACK; | |
477 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); | |
478 | } | |
479 | flush(pInfo); | |
1da177e4 LT |
480 | } |
481 | ||
482 | static void on_receive_block(struct r3964_info *pInfo) | |
483 | { | |
5e07e1cc JS |
484 | unsigned int length; |
485 | struct r3964_client_info *pClient; | |
486 | struct r3964_block_header *pBlock; | |
487 | ||
488 | length = pInfo->rx_position; | |
489 | ||
490 | /* compare byte checksum characters: */ | |
491 | if (pInfo->flags & R3964_BCC) { | |
492 | if (pInfo->bcc != pInfo->last_rx) { | |
493 | TRACE_PE("checksum error - got %x but expected %x", | |
494 | pInfo->last_rx, pInfo->bcc); | |
495 | pInfo->flags |= R3964_CHECKSUM; | |
496 | } | |
497 | } | |
498 | ||
499 | /* check for errors (parity, overrun,...): */ | |
500 | if (pInfo->flags & R3964_ERROR) { | |
501 | TRACE_PE("on_receive_block - transmission failed error %x", | |
502 | pInfo->flags & R3964_ERROR); | |
503 | ||
504 | put_char(pInfo, NAK); | |
505 | flush(pInfo); | |
506 | if (pInfo->nRetry < R3964_MAX_RETRIES) { | |
507 | pInfo->state = R3964_WAIT_FOR_RX_REPEAT; | |
508 | pInfo->nRetry++; | |
509 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC); | |
510 | } else { | |
511 | TRACE_PE("on_receive_block - failed after max retries"); | |
512 | pInfo->state = R3964_IDLE; | |
513 | } | |
514 | return; | |
515 | } | |
516 | ||
517 | /* received block; submit DLE: */ | |
518 | put_char(pInfo, DLE); | |
519 | flush(pInfo); | |
520 | del_timer_sync(&pInfo->tmr); | |
521 | TRACE_PS(" rx success: got %d chars", length); | |
522 | ||
523 | /* prepare struct r3964_block_header: */ | |
524 | pBlock = kmalloc(length + sizeof(struct r3964_block_header), | |
525 | GFP_KERNEL); | |
526 | TRACE_M("on_receive_block - kmalloc %p", pBlock); | |
527 | ||
528 | if (pBlock == NULL) | |
529 | return; | |
530 | ||
531 | pBlock->length = length; | |
532 | pBlock->data = ((unsigned char *)pBlock) + | |
533 | sizeof(struct r3964_block_header); | |
534 | pBlock->locks = 0; | |
535 | pBlock->next = NULL; | |
536 | pBlock->owner = NULL; | |
537 | ||
538 | memcpy(pBlock->data, pInfo->rx_buf, length); | |
539 | ||
540 | /* queue block into rx_queue: */ | |
541 | add_rx_queue(pInfo, pBlock); | |
542 | ||
543 | /* notify attached client processes: */ | |
544 | for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { | |
545 | if (pClient->sig_flags & R3964_SIG_DATA) { | |
546 | add_msg(pClient, R3964_MSG_DATA, length, R3964_OK, | |
547 | pBlock); | |
548 | } | |
549 | } | |
9b9ab1b3 | 550 | wake_up_interruptible(&pInfo->tty->read_wait); |
1da177e4 | 551 | |
5e07e1cc JS |
552 | pInfo->state = R3964_IDLE; |
553 | ||
554 | trigger_transmit(pInfo); | |
555 | } | |
1da177e4 LT |
556 | |
557 | static void receive_char(struct r3964_info *pInfo, const unsigned char c) | |
558 | { | |
5e07e1cc JS |
559 | switch (pInfo->state) { |
560 | case R3964_TX_REQUEST: | |
561 | if (c == DLE) { | |
562 | TRACE_PS("TX_REQUEST - got DLE"); | |
563 | ||
564 | pInfo->state = R3964_TRANSMITTING; | |
565 | pInfo->tx_position = 0; | |
566 | ||
567 | transmit_block(pInfo); | |
568 | } else if (c == STX) { | |
569 | if (pInfo->nRetry == 0) { | |
570 | TRACE_PE("TX_REQUEST - init conflict"); | |
571 | if (pInfo->priority == R3964_SLAVE) { | |
572 | goto start_receiving; | |
573 | } | |
574 | } else { | |
575 | TRACE_PE("TX_REQUEST - secondary init " | |
576 | "conflict!? Switching to SLAVE mode " | |
577 | "for next rx."); | |
578 | goto start_receiving; | |
579 | } | |
580 | } else { | |
581 | TRACE_PE("TX_REQUEST - char != DLE: %x", c); | |
582 | retry_transmit(pInfo); | |
583 | } | |
584 | break; | |
585 | case R3964_TRANSMITTING: | |
586 | if (c == NAK) { | |
587 | TRACE_PE("TRANSMITTING - got NAK"); | |
588 | retry_transmit(pInfo); | |
589 | } else { | |
590 | TRACE_PE("TRANSMITTING - got invalid char"); | |
591 | ||
592 | pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY; | |
593 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
594 | } | |
595 | break; | |
596 | case R3964_WAIT_FOR_TX_ACK: | |
597 | if (c == DLE) { | |
598 | TRACE_PS("WAIT_FOR_TX_ACK - got DLE"); | |
599 | remove_from_tx_queue(pInfo, R3964_OK); | |
600 | ||
601 | pInfo->state = R3964_IDLE; | |
602 | trigger_transmit(pInfo); | |
603 | } else { | |
604 | retry_transmit(pInfo); | |
605 | } | |
606 | break; | |
607 | case R3964_WAIT_FOR_RX_REPEAT: | |
af901ca1 | 608 | /* FALLTHROUGH */ |
5e07e1cc JS |
609 | case R3964_IDLE: |
610 | if (c == STX) { | |
611 | /* Prevent rx_queue from overflow: */ | |
612 | if (pInfo->blocks_in_rx_queue >= | |
613 | R3964_MAX_BLOCKS_IN_RX_QUEUE) { | |
614 | TRACE_PE("IDLE - got STX but no space in " | |
615 | "rx_queue!"); | |
616 | pInfo->state = R3964_WAIT_FOR_RX_BUF; | |
617 | mod_timer(&pInfo->tmr, | |
618 | jiffies + R3964_TO_NO_BUF); | |
619 | break; | |
620 | } | |
1da177e4 | 621 | start_receiving: |
5e07e1cc JS |
622 | /* Ok, start receiving: */ |
623 | TRACE_PS("IDLE - got STX"); | |
624 | pInfo->rx_position = 0; | |
625 | pInfo->last_rx = 0; | |
626 | pInfo->flags &= ~R3964_ERROR; | |
627 | pInfo->state = R3964_RECEIVING; | |
628 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
629 | pInfo->nRetry = 0; | |
630 | put_char(pInfo, DLE); | |
631 | flush(pInfo); | |
632 | pInfo->bcc = 0; | |
633 | } | |
634 | break; | |
635 | case R3964_RECEIVING: | |
636 | if (pInfo->rx_position < RX_BUF_SIZE) { | |
637 | pInfo->bcc ^= c; | |
638 | ||
639 | if (c == DLE) { | |
640 | if (pInfo->last_rx == DLE) { | |
641 | pInfo->last_rx = 0; | |
642 | goto char_to_buf; | |
643 | } | |
644 | pInfo->last_rx = DLE; | |
645 | break; | |
646 | } else if ((c == ETX) && (pInfo->last_rx == DLE)) { | |
647 | if (pInfo->flags & R3964_BCC) { | |
648 | pInfo->state = R3964_WAIT_FOR_BCC; | |
649 | mod_timer(&pInfo->tmr, | |
650 | jiffies + R3964_TO_ZVZ); | |
651 | } else { | |
652 | on_receive_block(pInfo); | |
653 | } | |
654 | } else { | |
655 | pInfo->last_rx = c; | |
1da177e4 | 656 | char_to_buf: |
5e07e1cc JS |
657 | pInfo->rx_buf[pInfo->rx_position++] = c; |
658 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); | |
659 | } | |
660 | } | |
661 | /* else: overflow-msg? BUF_SIZE>MTU; should not happen? */ | |
662 | break; | |
663 | case R3964_WAIT_FOR_BCC: | |
664 | pInfo->last_rx = c; | |
665 | on_receive_block(pInfo); | |
666 | break; | |
667 | } | |
1da177e4 LT |
668 | } |
669 | ||
670 | static void receive_error(struct r3964_info *pInfo, const char flag) | |
671 | { | |
5e07e1cc JS |
672 | switch (flag) { |
673 | case TTY_NORMAL: | |
674 | break; | |
675 | case TTY_BREAK: | |
676 | TRACE_PE("received break"); | |
677 | pInfo->flags |= R3964_BREAK; | |
678 | break; | |
679 | case TTY_PARITY: | |
680 | TRACE_PE("parity error"); | |
681 | pInfo->flags |= R3964_PARITY; | |
682 | break; | |
683 | case TTY_FRAME: | |
684 | TRACE_PE("frame error"); | |
685 | pInfo->flags |= R3964_FRAME; | |
686 | break; | |
687 | case TTY_OVERRUN: | |
688 | TRACE_PE("frame overrun"); | |
689 | pInfo->flags |= R3964_OVERRUN; | |
690 | break; | |
691 | default: | |
692 | TRACE_PE("receive_error - unknown flag %d", flag); | |
693 | pInfo->flags |= R3964_UNKNOWN; | |
694 | break; | |
695 | } | |
1da177e4 LT |
696 | } |
697 | ||
e99e88a9 | 698 | static void on_timeout(struct timer_list *t) |
1da177e4 | 699 | { |
e99e88a9 | 700 | struct r3964_info *pInfo = from_timer(pInfo, t, tmr); |
5e07e1cc JS |
701 | |
702 | switch (pInfo->state) { | |
703 | case R3964_TX_REQUEST: | |
704 | TRACE_PE("TX_REQUEST - timeout"); | |
705 | retry_transmit(pInfo); | |
706 | break; | |
707 | case R3964_WAIT_ZVZ_BEFORE_TX_RETRY: | |
708 | put_char(pInfo, NAK); | |
709 | flush(pInfo); | |
710 | retry_transmit(pInfo); | |
711 | break; | |
712 | case R3964_WAIT_FOR_TX_ACK: | |
713 | TRACE_PE("WAIT_FOR_TX_ACK - timeout"); | |
714 | retry_transmit(pInfo); | |
715 | break; | |
716 | case R3964_WAIT_FOR_RX_BUF: | |
717 | TRACE_PE("WAIT_FOR_RX_BUF - timeout"); | |
718 | put_char(pInfo, NAK); | |
719 | flush(pInfo); | |
720 | pInfo->state = R3964_IDLE; | |
721 | break; | |
722 | case R3964_RECEIVING: | |
723 | TRACE_PE("RECEIVING - timeout after %d chars", | |
724 | pInfo->rx_position); | |
725 | put_char(pInfo, NAK); | |
726 | flush(pInfo); | |
727 | pInfo->state = R3964_IDLE; | |
728 | break; | |
729 | case R3964_WAIT_FOR_RX_REPEAT: | |
730 | TRACE_PE("WAIT_FOR_RX_REPEAT - timeout"); | |
731 | pInfo->state = R3964_IDLE; | |
732 | break; | |
733 | case R3964_WAIT_FOR_BCC: | |
734 | TRACE_PE("WAIT_FOR_BCC - timeout"); | |
735 | put_char(pInfo, NAK); | |
736 | flush(pInfo); | |
737 | pInfo->state = R3964_IDLE; | |
738 | break; | |
739 | } | |
1da177e4 LT |
740 | } |
741 | ||
5e07e1cc JS |
742 | static struct r3964_client_info *findClient(struct r3964_info *pInfo, |
743 | struct pid *pid) | |
1da177e4 | 744 | { |
5e07e1cc JS |
745 | struct r3964_client_info *pClient; |
746 | ||
747 | for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { | |
748 | if (pClient->pid == pid) { | |
749 | return pClient; | |
750 | } | |
751 | } | |
752 | return NULL; | |
1da177e4 LT |
753 | } |
754 | ||
3cec556a | 755 | static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg) |
1da177e4 | 756 | { |
5e07e1cc JS |
757 | struct r3964_client_info *pClient; |
758 | struct r3964_client_info **ppClient; | |
759 | struct r3964_message *pMsg; | |
760 | ||
761 | if ((arg & R3964_SIG_ALL) == 0) { | |
762 | /* Remove client from client list */ | |
763 | for (ppClient = &pInfo->firstClient; *ppClient; | |
764 | ppClient = &(*ppClient)->next) { | |
765 | pClient = *ppClient; | |
766 | ||
767 | if (pClient->pid == pid) { | |
768 | TRACE_PS("removing client %d from client list", | |
769 | pid_nr(pid)); | |
770 | *ppClient = pClient->next; | |
771 | while (pClient->msg_count) { | |
772 | pMsg = remove_msg(pInfo, pClient); | |
773 | if (pMsg) { | |
774 | kfree(pMsg); | |
775 | TRACE_M("enable_signals - msg " | |
776 | "kfree %p", pMsg); | |
777 | } | |
778 | } | |
779 | put_pid(pClient->pid); | |
780 | kfree(pClient); | |
781 | TRACE_M("enable_signals - kfree %p", pClient); | |
782 | return 0; | |
783 | } | |
784 | } | |
785 | return -EINVAL; | |
786 | } else { | |
787 | pClient = findClient(pInfo, pid); | |
788 | if (pClient) { | |
789 | /* update signal options */ | |
790 | pClient->sig_flags = arg; | |
791 | } else { | |
792 | /* add client to client list */ | |
793 | pClient = kmalloc(sizeof(struct r3964_client_info), | |
794 | GFP_KERNEL); | |
795 | TRACE_M("enable_signals - kmalloc %p", pClient); | |
796 | if (pClient == NULL) | |
797 | return -ENOMEM; | |
798 | ||
799 | TRACE_PS("add client %d to client list", pid_nr(pid)); | |
800 | spin_lock_init(&pClient->lock); | |
801 | pClient->sig_flags = arg; | |
802 | pClient->pid = get_pid(pid); | |
803 | pClient->next = pInfo->firstClient; | |
804 | pClient->first_msg = NULL; | |
805 | pClient->last_msg = NULL; | |
806 | pClient->next_block_to_read = NULL; | |
807 | pClient->msg_count = 0; | |
808 | pInfo->firstClient = pClient; | |
809 | } | |
810 | } | |
811 | ||
812 | return 0; | |
1da177e4 LT |
813 | } |
814 | ||
5e07e1cc JS |
815 | static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
816 | unsigned char __user * buf) | |
1da177e4 | 817 | { |
5e07e1cc JS |
818 | struct r3964_client_info *pClient; |
819 | struct r3964_block_header *block; | |
820 | ||
821 | if (!buf) { | |
822 | return -EINVAL; | |
823 | } | |
824 | ||
825 | pClient = findClient(pInfo, pid); | |
826 | if (pClient == NULL) { | |
827 | return -EINVAL; | |
828 | } | |
829 | ||
830 | block = pClient->next_block_to_read; | |
831 | if (!block) { | |
832 | return 0; | |
833 | } else { | |
834 | if (copy_to_user(buf, block->data, block->length)) | |
835 | return -EFAULT; | |
836 | ||
837 | remove_client_block(pInfo, pClient); | |
838 | return block->length; | |
839 | } | |
840 | ||
841 | return -EINVAL; | |
1da177e4 LT |
842 | } |
843 | ||
844 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, | |
5e07e1cc | 845 | int error_code, struct r3964_block_header *pBlock) |
1da177e4 | 846 | { |
5e07e1cc JS |
847 | struct r3964_message *pMsg; |
848 | unsigned long flags; | |
849 | ||
850 | if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) { | |
1da177e4 LT |
851 | queue_the_message: |
852 | ||
5e07e1cc JS |
853 | pMsg = kmalloc(sizeof(struct r3964_message), |
854 | error_code ? GFP_ATOMIC : GFP_KERNEL); | |
855 | TRACE_M("add_msg - kmalloc %p", pMsg); | |
856 | if (pMsg == NULL) { | |
857 | return; | |
858 | } | |
859 | ||
860 | spin_lock_irqsave(&pClient->lock, flags); | |
861 | ||
862 | pMsg->msg_id = msg_id; | |
863 | pMsg->arg = arg; | |
864 | pMsg->error_code = error_code; | |
865 | pMsg->block = pBlock; | |
866 | pMsg->next = NULL; | |
867 | ||
868 | if (pClient->last_msg == NULL) { | |
869 | pClient->first_msg = pClient->last_msg = pMsg; | |
870 | } else { | |
871 | pClient->last_msg->next = pMsg; | |
872 | pClient->last_msg = pMsg; | |
873 | } | |
874 | ||
875 | pClient->msg_count++; | |
876 | ||
877 | if (pBlock != NULL) { | |
878 | pBlock->locks++; | |
879 | } | |
880 | spin_unlock_irqrestore(&pClient->lock, flags); | |
881 | } else { | |
882 | if ((pClient->last_msg->msg_id == R3964_MSG_ACK) | |
883 | && (pClient->last_msg->error_code == R3964_OVERFLOW)) { | |
884 | pClient->last_msg->arg++; | |
885 | TRACE_PE("add_msg - inc prev OVERFLOW-msg"); | |
886 | } else { | |
887 | msg_id = R3964_MSG_ACK; | |
888 | arg = 0; | |
889 | error_code = R3964_OVERFLOW; | |
890 | pBlock = NULL; | |
891 | TRACE_PE("add_msg - queue OVERFLOW-msg"); | |
892 | goto queue_the_message; | |
893 | } | |
894 | } | |
895 | /* Send SIGIO signal to client process: */ | |
896 | if (pClient->sig_flags & R3964_USE_SIGIO) { | |
897 | kill_pid(pClient->pid, SIGIO, 1); | |
898 | } | |
1da177e4 LT |
899 | } |
900 | ||
901 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, | |
5e07e1cc | 902 | struct r3964_client_info *pClient) |
1da177e4 | 903 | { |
5e07e1cc JS |
904 | struct r3964_message *pMsg = NULL; |
905 | unsigned long flags; | |
906 | ||
907 | if (pClient->first_msg) { | |
908 | spin_lock_irqsave(&pClient->lock, flags); | |
909 | ||
910 | pMsg = pClient->first_msg; | |
911 | pClient->first_msg = pMsg->next; | |
912 | if (pClient->first_msg == NULL) { | |
913 | pClient->last_msg = NULL; | |
914 | } | |
915 | ||
916 | pClient->msg_count--; | |
917 | if (pMsg->block) { | |
918 | remove_client_block(pInfo, pClient); | |
919 | pClient->next_block_to_read = pMsg->block; | |
920 | } | |
921 | spin_unlock_irqrestore(&pClient->lock, flags); | |
922 | } | |
923 | return pMsg; | |
1da177e4 LT |
924 | } |
925 | ||
5e07e1cc JS |
926 | static void remove_client_block(struct r3964_info *pInfo, |
927 | struct r3964_client_info *pClient) | |
1da177e4 | 928 | { |
5e07e1cc JS |
929 | struct r3964_block_header *block; |
930 | ||
931 | TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid)); | |
1da177e4 | 932 | |
5e07e1cc JS |
933 | block = pClient->next_block_to_read; |
934 | if (block) { | |
935 | block->locks--; | |
936 | if (block->locks == 0) { | |
937 | remove_from_rx_queue(pInfo, block); | |
938 | } | |
939 | } | |
940 | pClient->next_block_to_read = NULL; | |
941 | } | |
1da177e4 LT |
942 | |
943 | /************************************************************* | |
944 | * Line discipline routines | |
945 | *************************************************************/ | |
946 | ||
947 | static int r3964_open(struct tty_struct *tty) | |
948 | { | |
5e07e1cc JS |
949 | struct r3964_info *pInfo; |
950 | ||
951 | TRACE_L("open"); | |
952 | TRACE_L("tty=%p, PID=%d, disc_data=%p", | |
953 | tty, current->pid, tty->disc_data); | |
954 | ||
955 | pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL); | |
956 | TRACE_M("r3964_open - info kmalloc %p", pInfo); | |
957 | ||
958 | if (!pInfo) { | |
959 | printk(KERN_ERR "r3964: failed to alloc info structure\n"); | |
960 | return -ENOMEM; | |
961 | } | |
962 | ||
963 | pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL); | |
964 | TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf); | |
965 | ||
966 | if (!pInfo->rx_buf) { | |
967 | printk(KERN_ERR "r3964: failed to alloc receive buffer\n"); | |
968 | kfree(pInfo); | |
969 | TRACE_M("r3964_open - info kfree %p", pInfo); | |
970 | return -ENOMEM; | |
971 | } | |
972 | ||
973 | pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL); | |
974 | TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf); | |
975 | ||
976 | if (!pInfo->tx_buf) { | |
977 | printk(KERN_ERR "r3964: failed to alloc transmit buffer\n"); | |
978 | kfree(pInfo->rx_buf); | |
979 | TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf); | |
980 | kfree(pInfo); | |
981 | TRACE_M("r3964_open - info kfree %p", pInfo); | |
982 | return -ENOMEM; | |
983 | } | |
984 | ||
985 | spin_lock_init(&pInfo->lock); | |
aba24888 | 986 | mutex_init(&pInfo->read_lock); |
5e07e1cc | 987 | pInfo->tty = tty; |
5e07e1cc JS |
988 | pInfo->priority = R3964_MASTER; |
989 | pInfo->rx_first = pInfo->rx_last = NULL; | |
990 | pInfo->tx_first = pInfo->tx_last = NULL; | |
991 | pInfo->rx_position = 0; | |
992 | pInfo->tx_position = 0; | |
993 | pInfo->last_rx = 0; | |
994 | pInfo->blocks_in_rx_queue = 0; | |
995 | pInfo->firstClient = NULL; | |
996 | pInfo->state = R3964_IDLE; | |
997 | pInfo->flags = R3964_DEBUG; | |
998 | pInfo->nRetry = 0; | |
999 | ||
1000 | tty->disc_data = pInfo; | |
1001 | tty->receive_room = 65536; | |
1002 | ||
e99e88a9 | 1003 | timer_setup(&pInfo->tmr, on_timeout, 0); |
5e07e1cc JS |
1004 | |
1005 | return 0; | |
1da177e4 LT |
1006 | } |
1007 | ||
1008 | static void r3964_close(struct tty_struct *tty) | |
1009 | { | |
c9f19e96 | 1010 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1011 | struct r3964_client_info *pClient, *pNext; |
1012 | struct r3964_message *pMsg; | |
1013 | struct r3964_block_header *pHeader, *pNextHeader; | |
1014 | unsigned long flags; | |
1015 | ||
1016 | TRACE_L("close"); | |
1017 | ||
1018 | /* | |
1019 | * Make sure that our task queue isn't activated. If it | |
1020 | * is, take it out of the linked list. | |
1021 | */ | |
1022 | del_timer_sync(&pInfo->tmr); | |
1023 | ||
1024 | /* Remove client-structs and message queues: */ | |
1025 | pClient = pInfo->firstClient; | |
1026 | while (pClient) { | |
1027 | pNext = pClient->next; | |
1028 | while (pClient->msg_count) { | |
1029 | pMsg = remove_msg(pInfo, pClient); | |
1030 | if (pMsg) { | |
1031 | kfree(pMsg); | |
1032 | TRACE_M("r3964_close - msg kfree %p", pMsg); | |
1033 | } | |
1034 | } | |
1035 | put_pid(pClient->pid); | |
1036 | kfree(pClient); | |
1037 | TRACE_M("r3964_close - client kfree %p", pClient); | |
1038 | pClient = pNext; | |
1039 | } | |
1040 | /* Remove jobs from tx_queue: */ | |
1041 | spin_lock_irqsave(&pInfo->lock, flags); | |
1042 | pHeader = pInfo->tx_first; | |
1043 | pInfo->tx_first = pInfo->tx_last = NULL; | |
1da177e4 | 1044 | spin_unlock_irqrestore(&pInfo->lock, flags); |
5e07e1cc JS |
1045 | |
1046 | while (pHeader) { | |
1047 | pNextHeader = pHeader->next; | |
1048 | kfree(pHeader); | |
1049 | pHeader = pNextHeader; | |
1da177e4 LT |
1050 | } |
1051 | ||
5e07e1cc | 1052 | /* Free buffers: */ |
5e07e1cc JS |
1053 | kfree(pInfo->rx_buf); |
1054 | TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf); | |
1055 | kfree(pInfo->tx_buf); | |
1056 | TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf); | |
1057 | kfree(pInfo); | |
1058 | TRACE_M("r3964_close - info kfree %p", pInfo); | |
1da177e4 LT |
1059 | } |
1060 | ||
1061 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, | |
5e07e1cc | 1062 | unsigned char __user * buf, size_t nr) |
1da177e4 | 1063 | { |
c9f19e96 | 1064 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1065 | struct r3964_client_info *pClient; |
1066 | struct r3964_message *pMsg; | |
1067 | struct r3964_client_message theMsg; | |
eca41044 | 1068 | int ret; |
5e07e1cc JS |
1069 | |
1070 | TRACE_L("read()"); | |
1071 | ||
aba24888 PH |
1072 | /* |
1073 | * Internal serialization of reads. | |
1074 | */ | |
1075 | if (file->f_flags & O_NONBLOCK) { | |
1076 | if (!mutex_trylock(&pInfo->read_lock)) | |
1077 | return -EAGAIN; | |
1078 | } else { | |
1079 | if (mutex_lock_interruptible(&pInfo->read_lock)) | |
1080 | return -ERESTARTSYS; | |
1081 | } | |
04f378b1 | 1082 | |
5e07e1cc JS |
1083 | pClient = findClient(pInfo, task_pid(current)); |
1084 | if (pClient) { | |
1085 | pMsg = remove_msg(pInfo, pClient); | |
1086 | if (pMsg == NULL) { | |
1087 | /* no messages available. */ | |
c96cf923 | 1088 | if (tty_io_nonblock(tty, file)) { |
eca41044 JS |
1089 | ret = -EAGAIN; |
1090 | goto unlock; | |
5e07e1cc JS |
1091 | } |
1092 | /* block until there is a message: */ | |
aba24888 | 1093 | wait_event_interruptible(tty->read_wait, |
6defec13 | 1094 | (pMsg = remove_msg(pInfo, pClient))); |
5e07e1cc JS |
1095 | } |
1096 | ||
1097 | /* If we still haven't got a message, we must have been signalled */ | |
1098 | ||
04f378b1 | 1099 | if (!pMsg) { |
eca41044 JS |
1100 | ret = -EINTR; |
1101 | goto unlock; | |
04f378b1 | 1102 | } |
5e07e1cc JS |
1103 | |
1104 | /* deliver msg to client process: */ | |
1105 | theMsg.msg_id = pMsg->msg_id; | |
1106 | theMsg.arg = pMsg->arg; | |
1107 | theMsg.error_code = pMsg->error_code; | |
eca41044 | 1108 | ret = sizeof(struct r3964_client_message); |
5e07e1cc JS |
1109 | |
1110 | kfree(pMsg); | |
1111 | TRACE_M("r3964_read - msg kfree %p", pMsg); | |
1112 | ||
eca41044 JS |
1113 | if (copy_to_user(buf, &theMsg, ret)) { |
1114 | ret = -EFAULT; | |
1115 | goto unlock; | |
04f378b1 | 1116 | } |
5e07e1cc | 1117 | |
eca41044 JS |
1118 | TRACE_PS("read - return %d", ret); |
1119 | goto unlock; | |
5e07e1cc | 1120 | } |
eca41044 JS |
1121 | ret = -EPERM; |
1122 | unlock: | |
aba24888 | 1123 | mutex_unlock(&pInfo->read_lock); |
eca41044 | 1124 | return ret; |
1da177e4 LT |
1125 | } |
1126 | ||
5e07e1cc | 1127 | static ssize_t r3964_write(struct tty_struct *tty, struct file *file, |
1da177e4 LT |
1128 | const unsigned char *data, size_t count) |
1129 | { | |
c9f19e96 | 1130 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1131 | struct r3964_block_header *pHeader; |
1132 | struct r3964_client_info *pClient; | |
1133 | unsigned char *new_data; | |
1134 | ||
1135 | TRACE_L("write request, %d characters", count); | |
1da177e4 LT |
1136 | /* |
1137 | * Verify the pointers | |
1138 | */ | |
1139 | ||
5e07e1cc JS |
1140 | if (!pInfo) |
1141 | return -EIO; | |
1da177e4 LT |
1142 | |
1143 | /* | |
1144 | * Ensure that the caller does not wish to send too much. | |
1145 | */ | |
5e07e1cc JS |
1146 | if (count > R3964_MTU) { |
1147 | if (pInfo->flags & R3964_DEBUG) { | |
1148 | TRACE_L(KERN_WARNING "r3964_write: truncating user " | |
1149 | "packet from %u to mtu %d", count, R3964_MTU); | |
1150 | } | |
1151 | count = R3964_MTU; | |
1152 | } | |
1da177e4 LT |
1153 | /* |
1154 | * Allocate a buffer for the data and copy it from the buffer with header prepended | |
1155 | */ | |
5e07e1cc JS |
1156 | new_data = kmalloc(count + sizeof(struct r3964_block_header), |
1157 | GFP_KERNEL); | |
1158 | TRACE_M("r3964_write - kmalloc %p", new_data); | |
1159 | if (new_data == NULL) { | |
1160 | if (pInfo->flags & R3964_DEBUG) { | |
1161 | printk(KERN_ERR "r3964_write: no memory\n"); | |
1162 | } | |
1163 | return -ENOSPC; | |
1164 | } | |
1165 | ||
1166 | pHeader = (struct r3964_block_header *)new_data; | |
1167 | pHeader->data = new_data + sizeof(struct r3964_block_header); | |
1168 | pHeader->length = count; | |
1169 | pHeader->locks = 0; | |
1170 | pHeader->owner = NULL; | |
1171 | ||
1172 | pClient = findClient(pInfo, task_pid(current)); | |
1173 | if (pClient) { | |
1174 | pHeader->owner = pClient; | |
1175 | } | |
1176 | ||
1177 | memcpy(pHeader->data, data, count); /* We already verified this */ | |
1178 | ||
1179 | if (pInfo->flags & R3964_DEBUG) { | |
1180 | dump_block(pHeader->data, count); | |
1181 | } | |
1da177e4 LT |
1182 | |
1183 | /* | |
1184 | * Add buffer to transmit-queue: | |
1185 | */ | |
5e07e1cc JS |
1186 | add_tx_queue(pInfo, pHeader); |
1187 | trigger_transmit(pInfo); | |
1188 | ||
1189 | return 0; | |
1da177e4 LT |
1190 | } |
1191 | ||
5e07e1cc JS |
1192 | static int r3964_ioctl(struct tty_struct *tty, struct file *file, |
1193 | unsigned int cmd, unsigned long arg) | |
1da177e4 | 1194 | { |
c9f19e96 | 1195 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1196 | if (pInfo == NULL) |
1197 | return -EINVAL; | |
1198 | switch (cmd) { | |
1199 | case R3964_ENABLE_SIGNALS: | |
1200 | return enable_signals(pInfo, task_pid(current), arg); | |
1201 | case R3964_SETPRIORITY: | |
1202 | if (arg < R3964_MASTER || arg > R3964_SLAVE) | |
1203 | return -EINVAL; | |
1204 | pInfo->priority = arg & 0xff; | |
1205 | return 0; | |
1206 | case R3964_USE_BCC: | |
1207 | if (arg) | |
1208 | pInfo->flags |= R3964_BCC; | |
1209 | else | |
1210 | pInfo->flags &= ~R3964_BCC; | |
1211 | return 0; | |
1212 | case R3964_READ_TELEGRAM: | |
1213 | return read_telegram(pInfo, task_pid(current), | |
1214 | (unsigned char __user *)arg); | |
1215 | default: | |
1216 | return -ENOIOCTLCMD; | |
1217 | } | |
1da177e4 LT |
1218 | } |
1219 | ||
f0193d3e AV |
1220 | #ifdef CONFIG_COMPAT |
1221 | static int r3964_compat_ioctl(struct tty_struct *tty, struct file *file, | |
1222 | unsigned int cmd, unsigned long arg) | |
1223 | { | |
1224 | switch (cmd) { | |
1225 | case R3964_ENABLE_SIGNALS: | |
1226 | case R3964_SETPRIORITY: | |
1227 | case R3964_USE_BCC: | |
1228 | return r3964_ioctl(tty, file, cmd, arg); | |
1229 | default: | |
1230 | return -ENOIOCTLCMD; | |
1231 | } | |
1232 | } | |
1233 | #endif | |
1234 | ||
5e07e1cc | 1235 | static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old) |
1da177e4 | 1236 | { |
5e07e1cc | 1237 | TRACE_L("set_termios"); |
1da177e4 LT |
1238 | } |
1239 | ||
1240 | /* Called without the kernel lock held - fine */ | |
afc9a42b | 1241 | static __poll_t r3964_poll(struct tty_struct *tty, struct file *file, |
5e07e1cc | 1242 | struct poll_table_struct *wait) |
1da177e4 | 1243 | { |
c9f19e96 | 1244 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc JS |
1245 | struct r3964_client_info *pClient; |
1246 | struct r3964_message *pMsg = NULL; | |
1247 | unsigned long flags; | |
a9a08845 | 1248 | __poll_t result = EPOLLOUT; |
5e07e1cc JS |
1249 | |
1250 | TRACE_L("POLL"); | |
1251 | ||
1252 | pClient = findClient(pInfo, task_pid(current)); | |
1253 | if (pClient) { | |
9b9ab1b3 | 1254 | poll_wait(file, &tty->read_wait, wait); |
5e07e1cc JS |
1255 | spin_lock_irqsave(&pInfo->lock, flags); |
1256 | pMsg = pClient->first_msg; | |
1257 | spin_unlock_irqrestore(&pInfo->lock, flags); | |
1258 | if (pMsg) | |
a9a08845 | 1259 | result |= EPOLLIN | EPOLLRDNORM; |
5e07e1cc JS |
1260 | } else { |
1261 | result = -EINVAL; | |
1262 | } | |
1263 | return result; | |
1da177e4 LT |
1264 | } |
1265 | ||
55db4c64 LT |
1266 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
1267 | char *fp, int count) | |
1da177e4 | 1268 | { |
c9f19e96 | 1269 | struct r3964_info *pInfo = tty->disc_data; |
5e07e1cc | 1270 | const unsigned char *p; |
82f91fe0 | 1271 | char *f, flags = TTY_NORMAL; |
5e07e1cc JS |
1272 | int i; |
1273 | ||
1274 | for (i = count, p = cp, f = fp; i; i--, p++) { | |
1275 | if (f) | |
1276 | flags = *f++; | |
1277 | if (flags == TTY_NORMAL) { | |
1278 | receive_char(pInfo, *p); | |
1279 | } else { | |
1280 | receive_error(pInfo, flags); | |
1281 | } | |
1282 | ||
1283 | } | |
1da177e4 LT |
1284 | } |
1285 | ||
1da177e4 LT |
1286 | MODULE_LICENSE("GPL"); |
1287 | MODULE_ALIAS_LDISC(N_R3964); |