Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * PCBIT-D low-layer interface | |
3 | * | |
4 | * Copyright (C) 1996 Universidade de Lisboa | |
5 | * | |
6 | * Written by Pedro Roque Marques (roque@di.fc.ul.pt) | |
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 | ||
12 | /* | |
13 | * 19991203 - Fernando Carvalho - takion@superbofh.org | |
14 | * Hacked to compile with egcs and run with current version of isdn modules | |
15 | */ | |
16 | ||
17 | /* | |
18 | * Based on documentation provided by Inesc: | |
19 | * - "Interface com bus do PC para o PCBIT e PCBIT-D", Inesc, Jan 93 | |
20 | */ | |
21 | ||
22 | /* | |
23 | * TODO: better handling of errors | |
24 | * re-write/remove debug printks | |
25 | */ | |
26 | ||
1da177e4 LT |
27 | #include <linux/string.h> |
28 | #include <linux/kernel.h> | |
29 | #include <linux/types.h> | |
d43c36dc | 30 | #include <linux/sched.h> |
1da177e4 LT |
31 | #include <linux/slab.h> |
32 | #include <linux/interrupt.h> | |
33 | #include <linux/workqueue.h> | |
34 | #include <linux/mm.h> | |
35 | #include <linux/skbuff.h> | |
36 | ||
37 | #include <linux/isdnif.h> | |
38 | ||
39 | #include <asm/system.h> | |
40 | #include <asm/io.h> | |
41 | ||
42 | ||
43 | #include "pcbit.h" | |
44 | #include "layer2.h" | |
45 | #include "edss1.h" | |
46 | ||
47 | #undef DEBUG_FRAG | |
48 | ||
49 | ||
1da177e4 LT |
50 | /* |
51 | * Prototypes | |
52 | */ | |
53 | ||
1da177e4 LT |
54 | static void pcbit_transmit(struct pcbit_dev *dev); |
55 | ||
56 | static void pcbit_recv_ack(struct pcbit_dev *dev, unsigned char ack); | |
57 | ||
58 | static void pcbit_l2_error(struct pcbit_dev *dev); | |
59 | static void pcbit_l2_active_conf(struct pcbit_dev *dev, u_char info); | |
60 | static void pcbit_l2_err_recover(unsigned long data); | |
61 | ||
62 | static void pcbit_firmware_bug(struct pcbit_dev *dev); | |
63 | ||
64 | static __inline__ void | |
65 | pcbit_sched_delivery(struct pcbit_dev *dev) | |
66 | { | |
67 | schedule_work(&dev->qdelivery); | |
68 | } | |
69 | ||
70 | ||
71 | /* | |
72 | * Called from layer3 | |
73 | */ | |
74 | ||
75 | int | |
76 | pcbit_l2_write(struct pcbit_dev *dev, ulong msg, ushort refnum, | |
77 | struct sk_buff *skb, unsigned short hdr_len) | |
78 | { | |
79 | struct frame_buf *frame, | |
80 | *ptr; | |
81 | unsigned long flags; | |
82 | ||
83 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) { | |
84 | dev_kfree_skb(skb); | |
85 | return -1; | |
86 | } | |
5cbded58 | 87 | if ((frame = kmalloc(sizeof(struct frame_buf), |
1da177e4 LT |
88 | GFP_ATOMIC)) == NULL) { |
89 | printk(KERN_WARNING "pcbit_2_write: kmalloc failed\n"); | |
90 | dev_kfree_skb(skb); | |
91 | return -1; | |
92 | } | |
93 | frame->msg = msg; | |
94 | frame->refnum = refnum; | |
95 | frame->copied = 0; | |
96 | frame->hdr_len = hdr_len; | |
97 | ||
98 | if (skb) | |
99 | frame->dt_len = skb->len - hdr_len; | |
100 | else | |
101 | frame->dt_len = 0; | |
102 | ||
103 | frame->skb = skb; | |
104 | ||
105 | frame->next = NULL; | |
106 | ||
107 | spin_lock_irqsave(&dev->lock, flags); | |
108 | ||
109 | if (dev->write_queue == NULL) { | |
110 | dev->write_queue = frame; | |
111 | spin_unlock_irqrestore(&dev->lock, flags); | |
112 | pcbit_transmit(dev); | |
113 | } else { | |
114 | for (ptr = dev->write_queue; ptr->next; ptr = ptr->next); | |
115 | ptr->next = frame; | |
116 | ||
117 | spin_unlock_irqrestore(&dev->lock, flags); | |
118 | } | |
119 | return 0; | |
120 | } | |
121 | ||
122 | static __inline__ void | |
123 | pcbit_tx_update(struct pcbit_dev *dev, ushort len) | |
124 | { | |
125 | u_char info; | |
126 | ||
127 | dev->send_seq = (dev->send_seq + 1) % 8; | |
128 | ||
129 | dev->fsize[dev->send_seq] = len; | |
130 | info = 0; | |
131 | info |= dev->rcv_seq << 3; | |
132 | info |= dev->send_seq; | |
133 | ||
134 | writeb(info, dev->sh_mem + BANK4); | |
135 | ||
136 | } | |
137 | ||
138 | /* | |
139 | * called by interrupt service routine or by write_2 | |
140 | */ | |
141 | ||
142 | static void | |
143 | pcbit_transmit(struct pcbit_dev *dev) | |
144 | { | |
145 | struct frame_buf *frame = NULL; | |
146 | unsigned char unacked; | |
147 | int flen; /* fragment frame length including all headers */ | |
148 | int free; | |
149 | int count, | |
150 | cp_len; | |
151 | unsigned long flags; | |
152 | unsigned short tt; | |
153 | ||
154 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) | |
155 | return; | |
156 | ||
157 | unacked = (dev->send_seq + (8 - dev->unack_seq)) & 0x07; | |
158 | ||
159 | spin_lock_irqsave(&dev->lock, flags); | |
160 | ||
161 | if (dev->free > 16 && dev->write_queue && unacked < 7) { | |
162 | ||
163 | if (!dev->w_busy) | |
164 | dev->w_busy = 1; | |
165 | else { | |
166 | spin_unlock_irqrestore(&dev->lock, flags); | |
167 | return; | |
168 | } | |
169 | ||
170 | ||
171 | frame = dev->write_queue; | |
172 | free = dev->free; | |
173 | ||
174 | spin_unlock_irqrestore(&dev->lock, flags); | |
175 | ||
176 | if (frame->copied == 0) { | |
177 | ||
178 | /* Type 0 frame */ | |
179 | ||
180 | ulong msg; | |
181 | ||
182 | if (frame->skb) | |
183 | flen = FRAME_HDR_LEN + PREHDR_LEN + frame->skb->len; | |
184 | else | |
185 | flen = FRAME_HDR_LEN + PREHDR_LEN; | |
186 | ||
187 | if (flen > free) | |
188 | flen = free; | |
189 | ||
190 | msg = frame->msg; | |
191 | ||
192 | /* | |
193 | * Board level 2 header | |
194 | */ | |
195 | ||
196 | pcbit_writew(dev, flen - FRAME_HDR_LEN); | |
197 | ||
198 | pcbit_writeb(dev, GET_MSG_CPU(msg)); | |
199 | ||
200 | pcbit_writeb(dev, GET_MSG_PROC(msg)); | |
201 | ||
202 | /* TH */ | |
203 | pcbit_writew(dev, frame->hdr_len + PREHDR_LEN); | |
204 | ||
205 | /* TD */ | |
206 | pcbit_writew(dev, frame->dt_len); | |
207 | ||
208 | ||
209 | /* | |
210 | * Board level 3 fixed-header | |
211 | */ | |
212 | ||
213 | /* LEN = TH */ | |
214 | pcbit_writew(dev, frame->hdr_len + PREHDR_LEN); | |
215 | ||
216 | /* XX */ | |
217 | pcbit_writew(dev, 0); | |
218 | ||
219 | /* C + S */ | |
220 | pcbit_writeb(dev, GET_MSG_CMD(msg)); | |
221 | pcbit_writeb(dev, GET_MSG_SCMD(msg)); | |
222 | ||
223 | /* NUM */ | |
224 | pcbit_writew(dev, frame->refnum); | |
225 | ||
226 | count = FRAME_HDR_LEN + PREHDR_LEN; | |
227 | } else { | |
228 | /* Type 1 frame */ | |
229 | ||
230 | flen = 2 + (frame->skb->len - frame->copied); | |
231 | ||
232 | if (flen > free) | |
233 | flen = free; | |
234 | ||
235 | /* TT */ | |
236 | tt = ((ushort) (flen - 2)) | 0x8000U; /* Type 1 */ | |
237 | pcbit_writew(dev, tt); | |
238 | ||
239 | count = 2; | |
240 | } | |
241 | ||
242 | if (frame->skb) { | |
243 | cp_len = frame->skb->len - frame->copied; | |
244 | if (cp_len > flen - count) | |
245 | cp_len = flen - count; | |
246 | ||
247 | memcpy_topcbit(dev, frame->skb->data + frame->copied, | |
248 | cp_len); | |
249 | frame->copied += cp_len; | |
250 | } | |
251 | /* bookkeeping */ | |
252 | dev->free -= flen; | |
253 | pcbit_tx_update(dev, flen); | |
254 | ||
255 | spin_lock_irqsave(&dev->lock, flags); | |
256 | ||
257 | if (frame->skb == NULL || frame->copied == frame->skb->len) { | |
258 | ||
259 | dev->write_queue = frame->next; | |
260 | ||
261 | if (frame->skb != NULL) { | |
262 | /* free frame */ | |
263 | dev_kfree_skb(frame->skb); | |
264 | } | |
265 | kfree(frame); | |
266 | } | |
267 | dev->w_busy = 0; | |
268 | spin_unlock_irqrestore(&dev->lock, flags); | |
269 | } else { | |
270 | spin_unlock_irqrestore(&dev->lock, flags); | |
271 | #ifdef DEBUG | |
272 | printk(KERN_DEBUG "unacked %d free %d write_queue %s\n", | |
273 | unacked, dev->free, dev->write_queue ? "not empty" : | |
274 | "empty"); | |
275 | #endif | |
276 | } | |
277 | } | |
278 | ||
279 | ||
280 | /* | |
281 | * deliver a queued frame to the upper layer | |
282 | */ | |
283 | ||
284 | void | |
c4028958 | 285 | pcbit_deliver(struct work_struct *work) |
1da177e4 LT |
286 | { |
287 | struct frame_buf *frame; | |
288 | unsigned long flags, msg; | |
c4028958 DH |
289 | struct pcbit_dev *dev = |
290 | container_of(work, struct pcbit_dev, qdelivery); | |
1da177e4 LT |
291 | |
292 | spin_lock_irqsave(&dev->lock, flags); | |
293 | ||
294 | while ((frame = dev->read_queue)) { | |
295 | dev->read_queue = frame->next; | |
296 | spin_unlock_irqrestore(&dev->lock, flags); | |
297 | ||
76fd0209 | 298 | msg = 0; |
1da177e4 LT |
299 | SET_MSG_CPU(msg, 0); |
300 | SET_MSG_PROC(msg, 0); | |
301 | SET_MSG_CMD(msg, frame->skb->data[2]); | |
302 | SET_MSG_SCMD(msg, frame->skb->data[3]); | |
303 | ||
304 | frame->refnum = *((ushort *) frame->skb->data + 4); | |
305 | frame->msg = *((ulong *) & msg); | |
306 | ||
307 | skb_pull(frame->skb, 6); | |
308 | ||
309 | pcbit_l3_receive(dev, frame->msg, frame->skb, frame->hdr_len, | |
310 | frame->refnum); | |
311 | ||
312 | kfree(frame); | |
313 | ||
314 | spin_lock_irqsave(&dev->lock, flags); | |
315 | } | |
316 | ||
317 | spin_unlock_irqrestore(&dev->lock, flags); | |
318 | } | |
319 | ||
320 | /* | |
321 | * Reads BANK 2 & Reassembles | |
322 | */ | |
323 | ||
324 | static void | |
325 | pcbit_receive(struct pcbit_dev *dev) | |
326 | { | |
327 | unsigned short tt; | |
328 | u_char cpu, | |
329 | proc; | |
330 | struct frame_buf *frame = NULL; | |
331 | unsigned long flags; | |
332 | u_char type1; | |
333 | ||
334 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) | |
335 | return; | |
336 | ||
337 | tt = pcbit_readw(dev); | |
338 | ||
339 | if ((tt & 0x7fffU) > 511) { | |
340 | printk(KERN_INFO "pcbit: invalid frame length -> TT=%04x\n", | |
341 | tt); | |
342 | pcbit_l2_error(dev); | |
343 | return; | |
344 | } | |
345 | if (!(tt & 0x8000U)) { /* Type 0 */ | |
346 | type1 = 0; | |
347 | ||
348 | if (dev->read_frame) { | |
349 | printk(KERN_DEBUG "pcbit_receive: Type 0 frame and read_frame != NULL\n"); | |
350 | /* discard previous queued frame */ | |
d46604e1 | 351 | kfree_skb(dev->read_frame->skb); |
1da177e4 LT |
352 | kfree(dev->read_frame); |
353 | dev->read_frame = NULL; | |
354 | } | |
41f96935 | 355 | frame = kzalloc(sizeof(struct frame_buf), GFP_ATOMIC); |
1da177e4 LT |
356 | |
357 | if (frame == NULL) { | |
358 | printk(KERN_WARNING "kmalloc failed\n"); | |
359 | return; | |
360 | } | |
1da177e4 LT |
361 | |
362 | cpu = pcbit_readb(dev); | |
363 | proc = pcbit_readb(dev); | |
364 | ||
365 | ||
366 | if (cpu != 0x06 && cpu != 0x02) { | |
367 | printk(KERN_DEBUG "pcbit: invalid cpu value\n"); | |
368 | kfree(frame); | |
369 | pcbit_l2_error(dev); | |
370 | return; | |
371 | } | |
372 | /* | |
373 | * we discard cpu & proc on receiving | |
374 | * but we read it to update the pointer | |
375 | */ | |
376 | ||
377 | frame->hdr_len = pcbit_readw(dev); | |
378 | frame->dt_len = pcbit_readw(dev); | |
379 | ||
380 | /* | |
381 | * 0 sized packet | |
382 | * I don't know if they are an error or not... | |
383 | * But they are very frequent | |
384 | * Not documented | |
385 | */ | |
386 | ||
387 | if (frame->hdr_len == 0) { | |
388 | kfree(frame); | |
389 | #ifdef DEBUG | |
390 | printk(KERN_DEBUG "0 sized frame\n"); | |
391 | #endif | |
392 | pcbit_firmware_bug(dev); | |
393 | return; | |
394 | } | |
395 | /* sanity check the length values */ | |
396 | if (frame->hdr_len > 1024 || frame->dt_len > 2048) { | |
397 | #ifdef DEBUG | |
398 | printk(KERN_DEBUG "length problem: "); | |
399 | printk(KERN_DEBUG "TH=%04x TD=%04x\n", | |
400 | frame->hdr_len, | |
401 | frame->dt_len); | |
402 | #endif | |
403 | pcbit_l2_error(dev); | |
404 | kfree(frame); | |
405 | return; | |
406 | } | |
407 | /* minimum frame read */ | |
408 | ||
409 | frame->skb = dev_alloc_skb(frame->hdr_len + frame->dt_len + | |
410 | ((frame->hdr_len + 15) & ~15)); | |
411 | ||
412 | if (!frame->skb) { | |
413 | printk(KERN_DEBUG "pcbit_receive: out of memory\n"); | |
414 | kfree(frame); | |
415 | return; | |
416 | } | |
417 | /* 16 byte alignment for IP */ | |
418 | if (frame->dt_len) | |
419 | skb_reserve(frame->skb, (frame->hdr_len + 15) & ~15); | |
420 | ||
421 | } else { | |
422 | /* Type 1 */ | |
423 | type1 = 1; | |
424 | tt &= 0x7fffU; | |
425 | ||
426 | if (!(frame = dev->read_frame)) { | |
427 | printk("Type 1 frame and no frame queued\n"); | |
428 | /* usually after an error: toss frame */ | |
429 | dev->readptr += tt; | |
430 | if (dev->readptr > dev->sh_mem + BANK2 + BANKLEN) | |
431 | dev->readptr -= BANKLEN; | |
432 | return; | |
433 | ||
434 | } | |
435 | } | |
436 | ||
437 | memcpy_frompcbit(dev, skb_put(frame->skb, tt), tt); | |
438 | ||
439 | frame->copied += tt; | |
440 | spin_lock_irqsave(&dev->lock, flags); | |
441 | if (frame->copied == frame->hdr_len + frame->dt_len) { | |
442 | ||
443 | if (type1) { | |
444 | dev->read_frame = NULL; | |
445 | } | |
446 | if (dev->read_queue) { | |
447 | struct frame_buf *ptr; | |
448 | for (ptr = dev->read_queue; ptr->next; ptr = ptr->next); | |
449 | ptr->next = frame; | |
450 | } else | |
451 | dev->read_queue = frame; | |
452 | ||
453 | } else { | |
454 | dev->read_frame = frame; | |
455 | } | |
456 | spin_unlock_irqrestore(&dev->lock, flags); | |
457 | } | |
458 | ||
459 | /* | |
460 | * The board sends 0 sized frames | |
461 | * They are TDATA_CONFs that get messed up somehow | |
462 | * gotta send a fake acknowledgment to the upper layer somehow | |
463 | */ | |
464 | ||
465 | static __inline__ void | |
466 | pcbit_fake_conf(struct pcbit_dev *dev, struct pcbit_chan *chan) | |
467 | { | |
468 | isdn_ctrl ictl; | |
469 | ||
470 | if (chan->queued) { | |
471 | chan->queued--; | |
472 | ||
473 | ictl.driver = dev->id; | |
474 | ictl.command = ISDN_STAT_BSENT; | |
475 | ictl.arg = chan->id; | |
476 | dev->dev_if->statcallb(&ictl); | |
477 | } | |
478 | } | |
479 | ||
480 | static void | |
481 | pcbit_firmware_bug(struct pcbit_dev *dev) | |
482 | { | |
483 | struct pcbit_chan *chan; | |
484 | ||
485 | chan = dev->b1; | |
486 | ||
487 | if (chan->fsm_state == ST_ACTIVE) { | |
488 | pcbit_fake_conf(dev, chan); | |
489 | } | |
490 | chan = dev->b2; | |
491 | ||
492 | if (chan->fsm_state == ST_ACTIVE) { | |
493 | pcbit_fake_conf(dev, chan); | |
494 | } | |
495 | } | |
496 | ||
497 | irqreturn_t | |
7d12e780 | 498 | pcbit_irq_handler(int interrupt, void *devptr) |
1da177e4 LT |
499 | { |
500 | struct pcbit_dev *dev; | |
501 | u_char info, | |
502 | ack_seq, | |
503 | read_seq; | |
504 | ||
505 | dev = (struct pcbit_dev *) devptr; | |
506 | ||
507 | if (!dev) { | |
508 | printk(KERN_WARNING "pcbit_irq_handler: wrong device\n"); | |
509 | return IRQ_NONE; | |
510 | } | |
511 | if (dev->interrupt) { | |
512 | printk(KERN_DEBUG "pcbit: reentering interrupt hander\n"); | |
513 | return IRQ_HANDLED; | |
514 | } | |
515 | dev->interrupt = 1; | |
516 | ||
517 | info = readb(dev->sh_mem + BANK3); | |
518 | ||
519 | if (dev->l2_state == L2_STARTING || dev->l2_state == L2_ERROR) { | |
520 | pcbit_l2_active_conf(dev, info); | |
521 | dev->interrupt = 0; | |
522 | return IRQ_HANDLED; | |
523 | } | |
524 | if (info & 0x40U) { /* E bit set */ | |
525 | #ifdef DEBUG | |
526 | printk(KERN_DEBUG "pcbit_irq_handler: E bit on\n"); | |
527 | #endif | |
528 | pcbit_l2_error(dev); | |
529 | dev->interrupt = 0; | |
530 | return IRQ_HANDLED; | |
531 | } | |
532 | if (dev->l2_state != L2_RUNNING && dev->l2_state != L2_LOADING) { | |
533 | dev->interrupt = 0; | |
534 | return IRQ_HANDLED; | |
535 | } | |
536 | ack_seq = (info >> 3) & 0x07U; | |
537 | read_seq = (info & 0x07U); | |
538 | ||
539 | dev->interrupt = 0; | |
540 | ||
541 | if (read_seq != dev->rcv_seq) { | |
542 | while (read_seq != dev->rcv_seq) { | |
543 | pcbit_receive(dev); | |
544 | dev->rcv_seq = (dev->rcv_seq + 1) % 8; | |
545 | } | |
546 | pcbit_sched_delivery(dev); | |
547 | } | |
548 | if (ack_seq != dev->unack_seq) { | |
549 | pcbit_recv_ack(dev, ack_seq); | |
550 | } | |
551 | info = dev->rcv_seq << 3; | |
552 | info |= dev->send_seq; | |
553 | ||
554 | writeb(info, dev->sh_mem + BANK4); | |
555 | return IRQ_HANDLED; | |
556 | } | |
557 | ||
558 | ||
559 | static void | |
560 | pcbit_l2_active_conf(struct pcbit_dev *dev, u_char info) | |
561 | { | |
562 | u_char state; | |
563 | ||
564 | state = dev->l2_state; | |
565 | ||
566 | #ifdef DEBUG | |
567 | printk(KERN_DEBUG "layer2_active_confirm\n"); | |
568 | #endif | |
569 | ||
570 | ||
571 | if (info & 0x80U) { | |
572 | dev->rcv_seq = info & 0x07U; | |
573 | dev->l2_state = L2_RUNNING; | |
574 | } else | |
575 | dev->l2_state = L2_DOWN; | |
576 | ||
577 | if (state == L2_STARTING) | |
578 | wake_up_interruptible(&dev->set_running_wq); | |
579 | ||
580 | if (state == L2_ERROR && dev->l2_state == L2_RUNNING) { | |
581 | pcbit_transmit(dev); | |
582 | } | |
583 | } | |
584 | ||
585 | static void | |
586 | pcbit_l2_err_recover(unsigned long data) | |
587 | { | |
588 | ||
589 | struct pcbit_dev *dev; | |
590 | struct frame_buf *frame; | |
591 | ||
592 | dev = (struct pcbit_dev *) data; | |
593 | ||
594 | del_timer(&dev->error_recover_timer); | |
595 | if (dev->w_busy || dev->r_busy) { | |
596 | init_timer(&dev->error_recover_timer); | |
597 | dev->error_recover_timer.expires = jiffies + ERRTIME; | |
598 | add_timer(&dev->error_recover_timer); | |
599 | return; | |
600 | } | |
601 | dev->w_busy = dev->r_busy = 1; | |
602 | ||
603 | if (dev->read_frame) { | |
d46604e1 | 604 | kfree_skb(dev->read_frame->skb); |
1da177e4 LT |
605 | kfree(dev->read_frame); |
606 | dev->read_frame = NULL; | |
607 | } | |
608 | if (dev->write_queue) { | |
609 | frame = dev->write_queue; | |
610 | #ifdef FREE_ON_ERROR | |
611 | dev->write_queue = dev->write_queue->next; | |
612 | ||
613 | if (frame->skb) { | |
614 | dev_kfree_skb(frame->skb); | |
615 | } | |
616 | kfree(frame); | |
617 | #else | |
618 | frame->copied = 0; | |
619 | #endif | |
620 | } | |
621 | dev->rcv_seq = dev->send_seq = dev->unack_seq = 0; | |
622 | dev->free = 511; | |
623 | dev->l2_state = L2_ERROR; | |
624 | ||
625 | /* this is an hack... */ | |
626 | pcbit_firmware_bug(dev); | |
627 | ||
628 | dev->writeptr = dev->sh_mem; | |
629 | dev->readptr = dev->sh_mem + BANK2; | |
630 | ||
631 | writeb((0x80U | ((dev->rcv_seq & 0x07) << 3) | (dev->send_seq & 0x07)), | |
632 | dev->sh_mem + BANK4); | |
633 | dev->w_busy = dev->r_busy = 0; | |
634 | ||
635 | } | |
636 | ||
637 | static void | |
638 | pcbit_l2_error(struct pcbit_dev *dev) | |
639 | { | |
640 | if (dev->l2_state == L2_RUNNING) { | |
641 | ||
642 | printk(KERN_INFO "pcbit: layer 2 error\n"); | |
643 | ||
644 | #ifdef DEBUG | |
645 | log_state(dev); | |
646 | #endif | |
647 | ||
648 | dev->l2_state = L2_DOWN; | |
649 | ||
650 | init_timer(&dev->error_recover_timer); | |
651 | dev->error_recover_timer.function = &pcbit_l2_err_recover; | |
652 | dev->error_recover_timer.data = (ulong) dev; | |
653 | dev->error_recover_timer.expires = jiffies + ERRTIME; | |
654 | add_timer(&dev->error_recover_timer); | |
655 | } | |
656 | } | |
657 | ||
658 | /* | |
659 | * Description: | |
660 | * if board acks frames | |
661 | * update dev->free | |
662 | * call pcbit_transmit to write possible queued frames | |
663 | */ | |
664 | ||
665 | static void | |
666 | pcbit_recv_ack(struct pcbit_dev *dev, unsigned char ack) | |
667 | { | |
668 | int i, | |
669 | count; | |
670 | int unacked; | |
671 | ||
672 | unacked = (dev->send_seq + (8 - dev->unack_seq)) & 0x07; | |
673 | ||
674 | /* dev->unack_seq < ack <= dev->send_seq; */ | |
675 | ||
676 | if (unacked) { | |
677 | ||
678 | if (dev->send_seq > dev->unack_seq) { | |
679 | if (ack <= dev->unack_seq || ack > dev->send_seq) { | |
680 | printk(KERN_DEBUG | |
681 | "layer 2 ack unacceptable - dev %d", | |
682 | dev->id); | |
683 | ||
684 | pcbit_l2_error(dev); | |
685 | } else if (ack > dev->send_seq && ack <= dev->unack_seq) { | |
686 | printk(KERN_DEBUG | |
687 | "layer 2 ack unacceptable - dev %d", | |
688 | dev->id); | |
689 | pcbit_l2_error(dev); | |
690 | } | |
691 | } | |
692 | /* ack is acceptable */ | |
693 | ||
694 | ||
695 | i = dev->unack_seq; | |
696 | ||
697 | do { | |
698 | dev->unack_seq = i = (i + 1) % 8; | |
699 | dev->free += dev->fsize[i]; | |
700 | } while (i != ack); | |
701 | ||
702 | count = 0; | |
703 | while (count < 7 && dev->write_queue) { | |
704 | u8 lsend_seq = dev->send_seq; | |
705 | ||
706 | pcbit_transmit(dev); | |
707 | ||
708 | if (dev->send_seq == lsend_seq) | |
709 | break; | |
710 | count++; | |
711 | } | |
712 | } else | |
713 | printk(KERN_DEBUG "recv_ack: unacked = 0\n"); | |
714 | } |