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22#define pr_fmt(fmt) "(stc): " fmt
23#include <linux/module.h>
24#include <linux/kernel.h>
25#include <linux/init.h>
26#include <linux/tty.h>
27
28#include <linux/seq_file.h>
29#include <linux/skbuff.h>
30
31#include <linux/ti_wilink_st.h>
32
33
34
35
36
37void (*st_recv) (void*, const unsigned char*, long);
38
39
40static void add_channel_to_table(struct st_data_s *st_gdata,
41 struct st_proto_s *new_proto)
42{
43 pr_info("%s: id %d\n", __func__, new_proto->chnl_id);
44
45 st_gdata->list[new_proto->chnl_id] = new_proto;
46}
47
48static void remove_channel_from_table(struct st_data_s *st_gdata,
49 struct st_proto_s *proto)
50{
51 pr_info("%s: id %d\n", __func__, proto->chnl_id);
52 st_gdata->list[proto->chnl_id] = NULL;
53}
54
55
56
57
58
59
60
61
62int st_get_uart_wr_room(struct st_data_s *st_gdata)
63{
64 struct tty_struct *tty;
65 if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) {
66 pr_err("tty unavailable to perform write");
67 return -1;
68 }
69 tty = st_gdata->tty;
70 return tty->ops->write_room(tty);
71}
72
73
74
75
76
77
78
79
80int st_int_write(struct st_data_s *st_gdata,
81 const unsigned char *data, int count)
82{
83 struct tty_struct *tty;
84 if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) {
85 pr_err("tty unavailable to perform write");
86 return -EINVAL;
87 }
88 tty = st_gdata->tty;
89#ifdef VERBOSE
90 print_hex_dump(KERN_DEBUG, "<out<", DUMP_PREFIX_NONE,
91 16, 1, data, count, 0);
92#endif
93 return tty->ops->write(tty, data, count);
94
95}
96
97
98
99
100
101void st_send_frame(unsigned char chnl_id, struct st_data_s *st_gdata)
102{
103 pr_debug(" %s(prot:%d) ", __func__, chnl_id);
104
105 if (unlikely
106 (st_gdata == NULL || st_gdata->rx_skb == NULL
107 || st_gdata->list[chnl_id] == NULL)) {
108 pr_err("chnl_id %d not registered, no data to send?",
109 chnl_id);
110 kfree_skb(st_gdata->rx_skb);
111 return;
112 }
113
114
115
116
117
118 if (likely(st_gdata->list[chnl_id]->recv != NULL)) {
119 if (unlikely
120 (st_gdata->list[chnl_id]->recv
121 (st_gdata->list[chnl_id]->priv_data, st_gdata->rx_skb)
122 != 0)) {
123 pr_err(" proto stack %d's ->recv failed", chnl_id);
124 kfree_skb(st_gdata->rx_skb);
125 return;
126 }
127 } else {
128 pr_err(" proto stack %d's ->recv null", chnl_id);
129 kfree_skb(st_gdata->rx_skb);
130 }
131 return;
132}
133
134
135
136
137
138
139void st_reg_complete(struct st_data_s *st_gdata, char err)
140{
141 unsigned char i = 0;
142 pr_info(" %s ", __func__);
143 for (i = 0; i < ST_MAX_CHANNELS; i++) {
144 if (likely(st_gdata != NULL && st_gdata->list[i] != NULL &&
145 st_gdata->list[i]->reg_complete_cb != NULL)) {
146 st_gdata->list[i]->reg_complete_cb
147 (st_gdata->list[i]->priv_data, err);
148 pr_info("protocol %d's cb sent %d\n", i, err);
149 if (err) {
150 st_gdata->protos_registered--;
151 st_gdata->list[i] = NULL;
152 }
153 }
154 }
155}
156
157static inline int st_check_data_len(struct st_data_s *st_gdata,
158 unsigned char chnl_id, int len)
159{
160 int room = skb_tailroom(st_gdata->rx_skb);
161
162 pr_debug("len %d room %d", len, room);
163
164 if (!len) {
165
166
167
168
169 st_send_frame(chnl_id, st_gdata);
170
171 } else if (len > room) {
172
173
174
175 pr_err("Data length is too large len %d room %d", len,
176 room);
177 kfree_skb(st_gdata->rx_skb);
178 } else {
179
180
181
182 st_gdata->rx_state = ST_W4_DATA;
183 st_gdata->rx_count = len;
184 return len;
185 }
186
187
188
189 st_gdata->rx_state = ST_W4_PACKET_TYPE;
190 st_gdata->rx_skb = NULL;
191 st_gdata->rx_count = 0;
192 st_gdata->rx_chnl = 0;
193
194 return 0;
195}
196
197
198
199
200
201static inline void st_wakeup_ack(struct st_data_s *st_gdata,
202 unsigned char cmd)
203{
204 struct sk_buff *waiting_skb;
205 unsigned long flags = 0;
206
207 spin_lock_irqsave(&st_gdata->lock, flags);
208
209
210
211 while ((waiting_skb = skb_dequeue(&st_gdata->tx_waitq)))
212 skb_queue_tail(&st_gdata->txq, waiting_skb);
213
214
215 st_ll_sleep_state(st_gdata, (unsigned long)cmd);
216 spin_unlock_irqrestore(&st_gdata->lock, flags);
217
218
219 st_tx_wakeup(st_gdata);
220}
221
222
223
224
225
226
227
228
229
230void st_int_recv(void *disc_data,
231 const unsigned char *data, long count)
232{
233 char *ptr;
234 struct st_proto_s *proto;
235 unsigned short payload_len = 0;
236 int len = 0, type = 0;
237 unsigned char *plen;
238 struct st_data_s *st_gdata = (struct st_data_s *)disc_data;
239 unsigned long flags;
240
241 ptr = (char *)data;
242
243 if (unlikely(ptr == NULL) || (st_gdata == NULL)) {
244 pr_err(" received null from TTY ");
245 return;
246 }
247
248 pr_debug("count %ld rx_state %ld"
249 "rx_count %ld", count, st_gdata->rx_state,
250 st_gdata->rx_count);
251
252 spin_lock_irqsave(&st_gdata->lock, flags);
253
254 while (count) {
255 if (st_gdata->rx_count) {
256 len = min_t(unsigned int, st_gdata->rx_count, count);
257 memcpy(skb_put(st_gdata->rx_skb, len), ptr, len);
258 st_gdata->rx_count -= len;
259 count -= len;
260 ptr += len;
261
262 if (st_gdata->rx_count)
263 continue;
264
265
266 switch (st_gdata->rx_state) {
267
268 case ST_W4_DATA:
269 pr_debug("Complete pkt received");
270
271
272 st_send_frame(st_gdata->rx_chnl, st_gdata);
273
274 st_gdata->rx_state = ST_W4_PACKET_TYPE;
275 st_gdata->rx_skb = NULL;
276 continue;
277
278 case ST_W4_HEADER:
279 proto = st_gdata->list[st_gdata->rx_chnl];
280 plen =
281 &st_gdata->rx_skb->data
282 [proto->offset_len_in_hdr];
283 pr_debug("plen pointing to %x\n", *plen);
284 if (proto->len_size == 1)
285 payload_len = *(unsigned char *)plen;
286 else if (proto->len_size == 2)
287 payload_len =
288 __le16_to_cpu(*(unsigned short *)plen);
289 else
290 pr_info("%s: invalid length "
291 "for id %d\n",
292 __func__, proto->chnl_id);
293 st_check_data_len(st_gdata, proto->chnl_id,
294 payload_len);
295 pr_debug("off %d, pay len %d\n",
296 proto->offset_len_in_hdr, payload_len);
297 continue;
298 }
299 }
300
301
302
303
304 switch (*ptr) {
305 case LL_SLEEP_IND:
306 case LL_SLEEP_ACK:
307 case LL_WAKE_UP_IND:
308 pr_debug("PM packet");
309
310
311
312 st_ll_sleep_state(st_gdata, *ptr);
313
314
315
316 spin_unlock_irqrestore(&st_gdata->lock, flags);
317 if (st_ll_getstate(st_gdata) == ST_LL_AWAKE)
318 st_wakeup_ack(st_gdata, LL_WAKE_UP_ACK);
319 spin_lock_irqsave(&st_gdata->lock, flags);
320
321 ptr++;
322 count--;
323 continue;
324 case LL_WAKE_UP_ACK:
325 pr_debug("PM packet");
326
327 spin_unlock_irqrestore(&st_gdata->lock, flags);
328
329 st_wakeup_ack(st_gdata, *ptr);
330 spin_lock_irqsave(&st_gdata->lock, flags);
331
332 ptr++;
333 count--;
334 continue;
335
336 default:
337 type = *ptr;
338 st_gdata->rx_skb = alloc_skb(
339 st_gdata->list[type]->max_frame_size,
340 GFP_ATOMIC);
341 skb_reserve(st_gdata->rx_skb,
342 st_gdata->list[type]->reserve);
343
344 st_gdata->rx_skb->cb[0] = type;
345 st_gdata->rx_skb->cb[1] = 0;
346 st_gdata->rx_chnl = *ptr;
347 st_gdata->rx_state = ST_W4_HEADER;
348 st_gdata->rx_count = st_gdata->list[type]->hdr_len;
349 pr_debug("rx_count %ld\n", st_gdata->rx_count);
350 };
351 ptr++;
352 count--;
353 }
354 spin_unlock_irqrestore(&st_gdata->lock, flags);
355 pr_debug("done %s", __func__);
356 return;
357}
358
359
360
361
362
363
364
365struct sk_buff *st_int_dequeue(struct st_data_s *st_gdata)
366{
367 struct sk_buff *returning_skb;
368
369 pr_debug("%s", __func__);
370 if (st_gdata->tx_skb != NULL) {
371 returning_skb = st_gdata->tx_skb;
372 st_gdata->tx_skb = NULL;
373 return returning_skb;
374 }
375 return skb_dequeue(&st_gdata->txq);
376}
377
378
379
380
381
382
383
384
385
386
387void st_int_enqueue(struct st_data_s *st_gdata, struct sk_buff *skb)
388{
389 unsigned long flags = 0;
390
391 pr_debug("%s", __func__);
392 spin_lock_irqsave(&st_gdata->lock, flags);
393
394 switch (st_ll_getstate(st_gdata)) {
395 case ST_LL_AWAKE:
396 pr_debug("ST LL is AWAKE, sending normally");
397 skb_queue_tail(&st_gdata->txq, skb);
398 break;
399 case ST_LL_ASLEEP_TO_AWAKE:
400 skb_queue_tail(&st_gdata->tx_waitq, skb);
401 break;
402 case ST_LL_AWAKE_TO_ASLEEP:
403 pr_err("ST LL is illegal state(%ld),"
404 "purging received skb.", st_ll_getstate(st_gdata));
405 kfree_skb(skb);
406 break;
407 case ST_LL_ASLEEP:
408 skb_queue_tail(&st_gdata->tx_waitq, skb);
409 st_ll_wakeup(st_gdata);
410 break;
411 default:
412 pr_err("ST LL is illegal state(%ld),"
413 "purging received skb.", st_ll_getstate(st_gdata));
414 kfree_skb(skb);
415 break;
416 }
417
418 spin_unlock_irqrestore(&st_gdata->lock, flags);
419 pr_debug("done %s", __func__);
420 return;
421}
422
423
424
425
426
427
428
429void st_tx_wakeup(struct st_data_s *st_data)
430{
431 struct sk_buff *skb;
432 unsigned long flags;
433 pr_debug("%s", __func__);
434
435 if (test_and_set_bit(ST_TX_SENDING, &st_data->tx_state)) {
436 pr_debug("ST already sending");
437
438 set_bit(ST_TX_WAKEUP, &st_data->tx_state);
439 return;
440
441
442
443 }
444 do {
445
446 clear_bit(ST_TX_WAKEUP, &st_data->tx_state);
447 while ((skb = st_int_dequeue(st_data))) {
448 int len;
449 spin_lock_irqsave(&st_data->lock, flags);
450
451 set_bit(TTY_DO_WRITE_WAKEUP, &st_data->tty->flags);
452 len = st_int_write(st_data, skb->data, skb->len);
453 skb_pull(skb, len);
454
455 if (skb->len) {
456
457 st_data->tx_skb = skb;
458 spin_unlock_irqrestore(&st_data->lock, flags);
459 break;
460 }
461 kfree_skb(skb);
462 spin_unlock_irqrestore(&st_data->lock, flags);
463 }
464
465 } while (test_bit(ST_TX_WAKEUP, &st_data->tx_state));
466
467
468 clear_bit(ST_TX_SENDING, &st_data->tx_state);
469}
470
471
472
473
474void kim_st_list_protocols(struct st_data_s *st_gdata, void *buf)
475{
476 seq_printf(buf, "[%d]\nBT=%c\nFM=%c\nGPS=%c\n",
477 st_gdata->protos_registered,
478 st_gdata->list[0x04] != NULL ? 'R' : 'U',
479 st_gdata->list[0x08] != NULL ? 'R' : 'U',
480 st_gdata->list[0x09] != NULL ? 'R' : 'U');
481}
482
483
484
485
486
487
488long st_register(struct st_proto_s *new_proto)
489{
490 struct st_data_s *st_gdata;
491 long err = 0;
492 unsigned long flags = 0;
493
494 st_kim_ref(&st_gdata, 0);
495 pr_info("%s(%d) ", __func__, new_proto->chnl_id);
496 if (st_gdata == NULL || new_proto == NULL || new_proto->recv == NULL
497 || new_proto->reg_complete_cb == NULL) {
498 pr_err("gdata/new_proto/recv or reg_complete_cb not ready");
499 return -EINVAL;
500 }
501
502 if (new_proto->chnl_id >= ST_MAX_CHANNELS) {
503 pr_err("chnl_id %d not supported", new_proto->chnl_id);
504 return -EPROTONOSUPPORT;
505 }
506
507 if (st_gdata->list[new_proto->chnl_id] != NULL) {
508 pr_err("chnl_id %d already registered", new_proto->chnl_id);
509 return -EALREADY;
510 }
511
512
513 spin_lock_irqsave(&st_gdata->lock, flags);
514
515 if (test_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state)) {
516 pr_info(" ST_REG_IN_PROGRESS:%d ", new_proto->chnl_id);
517
518
519 add_channel_to_table(st_gdata, new_proto);
520 st_gdata->protos_registered++;
521 new_proto->write = st_write;
522
523 set_bit(ST_REG_PENDING, &st_gdata->st_state);
524 spin_unlock_irqrestore(&st_gdata->lock, flags);
525 return -EINPROGRESS;
526 } else if (st_gdata->protos_registered == ST_EMPTY) {
527 pr_info(" chnl_id list empty :%d ", new_proto->chnl_id);
528 set_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
529 st_recv = st_kim_recv;
530
531
532 spin_unlock_irqrestore(&st_gdata->lock, flags);
533
534
535 st_ll_enable(st_gdata);
536
537
538
539 err = st_kim_start(st_gdata->kim_data);
540 if (err != 0) {
541 clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
542 if ((st_gdata->protos_registered != ST_EMPTY) &&
543 (test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
544 pr_err(" KIM failure complete callback ");
545 st_reg_complete(st_gdata, err);
546 }
547 return -EINVAL;
548 }
549
550 clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state);
551 st_recv = st_int_recv;
552
553
554
555
556 if ((st_gdata->protos_registered != ST_EMPTY) &&
557 (test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
558 pr_debug(" call reg complete callback ");
559 st_reg_complete(st_gdata, 0);
560 }
561 clear_bit(ST_REG_PENDING, &st_gdata->st_state);
562
563
564
565
566 if (st_gdata->list[new_proto->chnl_id] != NULL) {
567 pr_err(" proto %d already registered ",
568 new_proto->chnl_id);
569 return -EALREADY;
570 }
571
572 spin_lock_irqsave(&st_gdata->lock, flags);
573 add_channel_to_table(st_gdata, new_proto);
574 st_gdata->protos_registered++;
575 new_proto->write = st_write;
576 spin_unlock_irqrestore(&st_gdata->lock, flags);
577 return err;
578 }
579
580 else {
581 add_channel_to_table(st_gdata, new_proto);
582 st_gdata->protos_registered++;
583 new_proto->write = st_write;
584
585
586 spin_unlock_irqrestore(&st_gdata->lock, flags);
587 return err;
588 }
589 pr_debug("done %s(%d) ", __func__, new_proto->chnl_id);
590}
591EXPORT_SYMBOL_GPL(st_register);
592
593
594
595
596long st_unregister(struct st_proto_s *proto)
597{
598 long err = 0;
599 unsigned long flags = 0;
600 struct st_data_s *st_gdata;
601
602 pr_debug("%s: %d ", __func__, proto->chnl_id);
603
604 st_kim_ref(&st_gdata, 0);
605 if (proto->chnl_id >= ST_MAX_CHANNELS) {
606 pr_err(" chnl_id %d not supported", proto->chnl_id);
607 return -EPROTONOSUPPORT;
608 }
609
610 spin_lock_irqsave(&st_gdata->lock, flags);
611
612 if (st_gdata->list[proto->chnl_id] == NULL) {
613 pr_err(" chnl_id %d not registered", proto->chnl_id);
614 spin_unlock_irqrestore(&st_gdata->lock, flags);
615 return -EPROTONOSUPPORT;
616 }
617
618 st_gdata->protos_registered--;
619 remove_channel_from_table(st_gdata, proto);
620 spin_unlock_irqrestore(&st_gdata->lock, flags);
621
622 if ((st_gdata->protos_registered == ST_EMPTY) &&
623 (!test_bit(ST_REG_PENDING, &st_gdata->st_state))) {
624 pr_info(" all chnl_ids unregistered ");
625
626
627 if (st_gdata->tty) {
628 tty_ldisc_flush(st_gdata->tty);
629 stop_tty(st_gdata->tty);
630 }
631
632
633 st_kim_stop(st_gdata->kim_data);
634
635 st_ll_disable(st_gdata);
636 }
637 return err;
638}
639
640
641
642
643
644long st_write(struct sk_buff *skb)
645{
646 struct st_data_s *st_gdata;
647 long len;
648
649 st_kim_ref(&st_gdata, 0);
650 if (unlikely(skb == NULL || st_gdata == NULL
651 || st_gdata->tty == NULL)) {
652 pr_err("data/tty unavailable to perform write");
653 return -EINVAL;
654 }
655
656 pr_debug("%d to be written", skb->len);
657 len = skb->len;
658
659
660 st_int_enqueue(st_gdata, skb);
661
662 st_tx_wakeup(st_gdata);
663
664
665 return len;
666}
667
668
669EXPORT_SYMBOL_GPL(st_unregister);
670
671
672
673
674
675static int st_tty_open(struct tty_struct *tty)
676{
677 int err = 0;
678 struct st_data_s *st_gdata;
679 pr_info("%s ", __func__);
680
681 st_kim_ref(&st_gdata, 0);
682 st_gdata->tty = tty;
683 tty->disc_data = st_gdata;
684
685
686 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
687
688
689
690 tty->receive_room = 65536;
691
692 tty_ldisc_flush(tty);
693 tty_driver_flush_buffer(tty);
694
695
696
697
698 st_kim_complete(st_gdata->kim_data);
699 pr_debug("done %s", __func__);
700 return err;
701}
702
703static void st_tty_close(struct tty_struct *tty)
704{
705 unsigned char i = ST_MAX_CHANNELS;
706 unsigned long flags = 0;
707 struct st_data_s *st_gdata = tty->disc_data;
708
709 pr_info("%s ", __func__);
710
711
712
713
714
715 spin_lock_irqsave(&st_gdata->lock, flags);
716 for (i = ST_BT; i < ST_MAX_CHANNELS; i++) {
717 if (st_gdata->list[i] != NULL)
718 pr_err("%d not un-registered", i);
719 st_gdata->list[i] = NULL;
720 }
721 st_gdata->protos_registered = 0;
722 spin_unlock_irqrestore(&st_gdata->lock, flags);
723
724
725
726
727 st_kim_complete(st_gdata->kim_data);
728 st_gdata->tty = NULL;
729
730 tty_ldisc_flush(tty);
731 tty_driver_flush_buffer(tty);
732
733 spin_lock_irqsave(&st_gdata->lock, flags);
734
735 skb_queue_purge(&st_gdata->txq);
736 skb_queue_purge(&st_gdata->tx_waitq);
737
738 st_gdata->rx_count = 0;
739 st_gdata->rx_state = ST_W4_PACKET_TYPE;
740 kfree_skb(st_gdata->rx_skb);
741 st_gdata->rx_skb = NULL;
742 spin_unlock_irqrestore(&st_gdata->lock, flags);
743
744 pr_debug("%s: done ", __func__);
745}
746
747static void st_tty_receive(struct tty_struct *tty, const unsigned char *data,
748 char *tty_flags, int count)
749{
750#ifdef VERBOSE
751 print_hex_dump(KERN_DEBUG, ">in>", DUMP_PREFIX_NONE,
752 16, 1, data, count, 0);
753#endif
754
755
756
757
758
759 st_recv(tty->disc_data, data, count);
760 pr_debug("done %s", __func__);
761}
762
763
764
765
766static void st_tty_wakeup(struct tty_struct *tty)
767{
768 struct st_data_s *st_gdata = tty->disc_data;
769 pr_debug("%s ", __func__);
770
771 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
772
773
774 st_tx_wakeup((void *)st_gdata);
775}
776
777static void st_tty_flush_buffer(struct tty_struct *tty)
778{
779 struct st_data_s *st_gdata = tty->disc_data;
780 pr_debug("%s ", __func__);
781
782 kfree_skb(st_gdata->tx_skb);
783 st_gdata->tx_skb = NULL;
784
785 tty->ops->flush_buffer(tty);
786 return;
787}
788
789static struct tty_ldisc_ops st_ldisc_ops = {
790 .magic = TTY_LDISC_MAGIC,
791 .name = "n_st",
792 .open = st_tty_open,
793 .close = st_tty_close,
794 .receive_buf = st_tty_receive,
795 .write_wakeup = st_tty_wakeup,
796 .flush_buffer = st_tty_flush_buffer,
797 .owner = THIS_MODULE
798};
799
800
801int st_core_init(struct st_data_s **core_data)
802{
803 struct st_data_s *st_gdata;
804 long err;
805
806 err = tty_register_ldisc(N_TI_WL, &st_ldisc_ops);
807 if (err) {
808 pr_err("error registering %d line discipline %ld",
809 N_TI_WL, err);
810 return err;
811 }
812 pr_debug("registered n_shared line discipline");
813
814 st_gdata = kzalloc(sizeof(struct st_data_s), GFP_KERNEL);
815 if (!st_gdata) {
816 pr_err("memory allocation failed");
817 err = tty_unregister_ldisc(N_TI_WL);
818 if (err)
819 pr_err("unable to un-register ldisc %ld", err);
820 err = -ENOMEM;
821 return err;
822 }
823
824
825
826
827 skb_queue_head_init(&st_gdata->txq);
828 skb_queue_head_init(&st_gdata->tx_waitq);
829
830
831 spin_lock_init(&st_gdata->lock);
832
833 err = st_ll_init(st_gdata);
834 if (err) {
835 pr_err("error during st_ll initialization(%ld)", err);
836 kfree(st_gdata);
837 err = tty_unregister_ldisc(N_TI_WL);
838 if (err)
839 pr_err("unable to un-register ldisc");
840 return err;
841 }
842 *core_data = st_gdata;
843 return 0;
844}
845
846void st_core_exit(struct st_data_s *st_gdata)
847{
848 long err;
849
850 err = st_ll_deinit(st_gdata);
851 if (err)
852 pr_err("error during deinit of ST LL %ld", err);
853
854 if (st_gdata != NULL) {
855
856 skb_queue_purge(&st_gdata->txq);
857 skb_queue_purge(&st_gdata->tx_waitq);
858 kfree_skb(st_gdata->rx_skb);
859 kfree_skb(st_gdata->tx_skb);
860
861 err = tty_unregister_ldisc(N_TI_WL);
862 if (err)
863 pr_err("unable to un-register ldisc %ld", err);
864
865 kfree(st_gdata);
866 }
867}
868
869
870