2 * Copyright (C) 2012 Intel Corporation. All rights reserved.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the
16 * Free Software Foundation, Inc.,
17 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 #define pr_fmt(fmt) "shdlc: %s: " fmt, __func__
22 #include <linux/sched.h>
23 #include <linux/export.h>
24 #include <linux/wait.h>
25 #include <linux/crc-ccitt.h>
26 #include <linux/slab.h>
27 #include <linux/skbuff.h>
29 #include <net/nfc/hci.h>
30 #include <net/nfc/shdlc.h>
32 #define SHDLC_LLC_HEAD_ROOM 2
33 #define SHDLC_LLC_TAIL_ROOM 2
35 #define SHDLC_MAX_WINDOW 4
36 #define SHDLC_SREJ_SUPPORT false
38 #define SHDLC_CONTROL_HEAD_MASK 0xe0
39 #define SHDLC_CONTROL_HEAD_I 0x80
40 #define SHDLC_CONTROL_HEAD_I2 0xa0
41 #define SHDLC_CONTROL_HEAD_S 0xc0
42 #define SHDLC_CONTROL_HEAD_U 0xe0
44 #define SHDLC_CONTROL_NS_MASK 0x38
45 #define SHDLC_CONTROL_NR_MASK 0x07
46 #define SHDLC_CONTROL_TYPE_MASK 0x18
48 #define SHDLC_CONTROL_M_MASK 0x1f
57 enum uframe_modifier {
62 #define SHDLC_CONNECT_VALUE_MS 5
63 #define SHDLC_T1_VALUE_MS(w) ((5 * w) / 4)
64 #define SHDLC_T2_VALUE_MS 300
66 #define SHDLC_DUMP_SKB(info, skb) \
68 pr_debug("%s:\n", info); \
69 print_hex_dump(KERN_DEBUG, "shdlc: ", DUMP_PREFIX_OFFSET, \
70 16, 1, skb->data, skb->len, 0); \
73 /* checks x < y <= z modulo 8 */
74 static bool nfc_shdlc_x_lt_y_lteq_z(int x, int y, int z)
77 return ((x < y) && (y <= z)) ? true : false;
79 return ((y > x) || (y <= z)) ? true : false;
82 /* checks x <= y < z modulo 8 */
83 static bool nfc_shdlc_x_lteq_y_lt_z(int x, int y, int z)
86 return ((x <= y) && (y < z)) ? true : false;
87 else /* x > z -> z+8 > x */
88 return ((y >= x) || (y < z)) ? true : false;
91 static struct sk_buff *nfc_shdlc_alloc_skb(struct nfc_shdlc *shdlc,
96 skb = alloc_skb(shdlc->client_headroom + SHDLC_LLC_HEAD_ROOM +
97 shdlc->client_tailroom + SHDLC_LLC_TAIL_ROOM +
98 payload_len, GFP_KERNEL);
100 skb_reserve(skb, shdlc->client_headroom + SHDLC_LLC_HEAD_ROOM);
105 static void nfc_shdlc_add_len_crc(struct sk_buff *skb)
111 *skb_push(skb, 1) = len;
113 crc = crc_ccitt(0xffff, skb->data, skb->len);
115 *skb_put(skb, 1) = crc & 0xff;
116 *skb_put(skb, 1) = crc >> 8;
119 /* immediately sends an S frame. */
120 static int nfc_shdlc_send_s_frame(struct nfc_shdlc *shdlc,
121 enum sframe_type sframe_type, int nr)
126 pr_debug("sframe_type=%d nr=%d\n", sframe_type, nr);
128 skb = nfc_shdlc_alloc_skb(shdlc, 0);
132 *skb_push(skb, 1) = SHDLC_CONTROL_HEAD_S | (sframe_type << 3) | nr;
134 nfc_shdlc_add_len_crc(skb);
136 r = shdlc->ops->xmit(shdlc, skb);
143 /* immediately sends an U frame. skb may contain optional payload */
144 static int nfc_shdlc_send_u_frame(struct nfc_shdlc *shdlc,
146 enum uframe_modifier uframe_modifier)
150 pr_debug("uframe_modifier=%d\n", uframe_modifier);
152 *skb_push(skb, 1) = SHDLC_CONTROL_HEAD_U | uframe_modifier;
154 nfc_shdlc_add_len_crc(skb);
156 r = shdlc->ops->xmit(shdlc, skb);
164 * Free ack_pending frames until y_nr - 1, and reset t2 according to
165 * the remaining oldest ack_pending frame sent time
167 static void nfc_shdlc_reset_t2(struct nfc_shdlc *shdlc, int y_nr)
170 int dnr = shdlc->dnr; /* MUST initially be < y_nr */
172 pr_debug("release ack pending up to frame %d excluded\n", y_nr);
174 while (dnr != y_nr) {
175 pr_debug("release ack pending frame %d\n", dnr);
177 skb = skb_dequeue(&shdlc->ack_pending_q);
183 if (skb_queue_empty(&shdlc->ack_pending_q)) {
184 if (shdlc->t2_active) {
185 del_timer_sync(&shdlc->t2_timer);
186 shdlc->t2_active = false;
189 ("All sent frames acked. Stopped T2(retransmit)\n");
192 skb = skb_peek(&shdlc->ack_pending_q);
194 mod_timer(&shdlc->t2_timer, *(unsigned long *)skb->cb +
195 msecs_to_jiffies(SHDLC_T2_VALUE_MS));
196 shdlc->t2_active = true;
199 ("Start T2(retransmit) for remaining unacked sent frames\n");
204 * Receive validated frames from lower layer. skb contains HCI payload only.
205 * Handle according to algorithm at spec:10.8.2
207 static void nfc_shdlc_rcv_i_frame(struct nfc_shdlc *shdlc,
208 struct sk_buff *skb, int ns, int nr)
213 pr_debug("recvd I-frame %d, remote waiting frame %d\n", ns, nr);
215 if (shdlc->state != SHDLC_CONNECTED)
218 if (x_ns != shdlc->nr) {
219 nfc_shdlc_send_s_frame(shdlc, S_FRAME_REJ, shdlc->nr);
223 if (shdlc->t1_active == false) {
224 shdlc->t1_active = true;
225 mod_timer(&shdlc->t1_timer,
226 msecs_to_jiffies(SHDLC_T1_VALUE_MS(shdlc->w)));
227 pr_debug("(re)Start T1(send ack)\n");
231 nfc_hci_recv_frame(shdlc->hdev, skb);
235 shdlc->nr = (shdlc->nr + 1) % 8;
237 if (nfc_shdlc_x_lt_y_lteq_z(shdlc->dnr, y_nr, shdlc->ns)) {
238 nfc_shdlc_reset_t2(shdlc, y_nr);
247 static void nfc_shdlc_rcv_ack(struct nfc_shdlc *shdlc, int y_nr)
249 pr_debug("remote acked up to frame %d excluded\n", y_nr);
251 if (nfc_shdlc_x_lt_y_lteq_z(shdlc->dnr, y_nr, shdlc->ns)) {
252 nfc_shdlc_reset_t2(shdlc, y_nr);
257 static void nfc_shdlc_requeue_ack_pending(struct nfc_shdlc *shdlc)
261 pr_debug("ns reset to %d\n", shdlc->dnr);
263 while ((skb = skb_dequeue_tail(&shdlc->ack_pending_q))) {
264 skb_pull(skb, 2); /* remove len+control */
265 skb_trim(skb, skb->len - 2); /* remove crc */
266 skb_queue_head(&shdlc->send_q, skb);
268 shdlc->ns = shdlc->dnr;
271 static void nfc_shdlc_rcv_rej(struct nfc_shdlc *shdlc, int y_nr)
275 pr_debug("remote asks retransmition from frame %d\n", y_nr);
277 if (nfc_shdlc_x_lteq_y_lt_z(shdlc->dnr, y_nr, shdlc->ns)) {
278 if (shdlc->t2_active) {
279 del_timer_sync(&shdlc->t2_timer);
280 shdlc->t2_active = false;
281 pr_debug("Stopped T2(retransmit)\n");
284 if (shdlc->dnr != y_nr) {
285 while ((shdlc->dnr = ((shdlc->dnr + 1) % 8)) != y_nr) {
286 skb = skb_dequeue(&shdlc->ack_pending_q);
291 nfc_shdlc_requeue_ack_pending(shdlc);
295 /* See spec RR:10.8.3 REJ:10.8.4 */
296 static void nfc_shdlc_rcv_s_frame(struct nfc_shdlc *shdlc,
297 enum sframe_type s_frame_type, int nr)
301 if (shdlc->state != SHDLC_CONNECTED)
304 switch (s_frame_type) {
306 nfc_shdlc_rcv_ack(shdlc, nr);
307 if (shdlc->rnr == true) { /* see SHDLC 10.7.7 */
309 if (shdlc->send_q.qlen == 0) {
310 skb = nfc_shdlc_alloc_skb(shdlc, 0);
312 skb_queue_tail(&shdlc->send_q, skb);
317 nfc_shdlc_rcv_rej(shdlc, nr);
320 nfc_shdlc_rcv_ack(shdlc, nr);
328 static void nfc_shdlc_connect_complete(struct nfc_shdlc *shdlc, int r)
330 pr_debug("result=%d\n", r);
332 del_timer_sync(&shdlc->connect_timer);
339 shdlc->state = SHDLC_CONNECTED;
341 shdlc->state = SHDLC_DISCONNECTED;
344 shdlc->connect_result = r;
346 wake_up(shdlc->connect_wq);
349 static int nfc_shdlc_connect_initiate(struct nfc_shdlc *shdlc)
355 skb = nfc_shdlc_alloc_skb(shdlc, 2);
359 *skb_put(skb, 1) = SHDLC_MAX_WINDOW;
360 *skb_put(skb, 1) = SHDLC_SREJ_SUPPORT ? 1 : 0;
362 return nfc_shdlc_send_u_frame(shdlc, skb, U_FRAME_RSET);
365 static int nfc_shdlc_connect_send_ua(struct nfc_shdlc *shdlc)
371 skb = nfc_shdlc_alloc_skb(shdlc, 0);
375 return nfc_shdlc_send_u_frame(shdlc, skb, U_FRAME_UA);
378 static void nfc_shdlc_rcv_u_frame(struct nfc_shdlc *shdlc,
380 enum uframe_modifier u_frame_modifier)
382 u8 w = SHDLC_MAX_WINDOW;
383 bool srej_support = SHDLC_SREJ_SUPPORT;
386 pr_debug("u_frame_modifier=%d\n", u_frame_modifier);
388 switch (u_frame_modifier) {
390 if (shdlc->state == SHDLC_NEGOCIATING) {
391 /* we sent RSET, but chip wants to negociate */
396 srej_support = skb->data[1] & 0x01 ? true :
399 if ((w <= SHDLC_MAX_WINDOW) &&
400 (SHDLC_SREJ_SUPPORT || (srej_support == false))) {
402 shdlc->srej_support = srej_support;
403 r = nfc_shdlc_connect_send_ua(shdlc);
404 nfc_shdlc_connect_complete(shdlc, r);
406 } else if (shdlc->state == SHDLC_CONNECTED) {
408 * Chip wants to reset link. This is unexpected and
411 shdlc->hard_fault = -ECONNRESET;
415 if ((shdlc->state == SHDLC_CONNECTING &&
416 shdlc->connect_tries > 0) ||
417 (shdlc->state == SHDLC_NEGOCIATING))
418 nfc_shdlc_connect_complete(shdlc, 0);
427 static void nfc_shdlc_handle_rcv_queue(struct nfc_shdlc *shdlc)
433 enum sframe_type s_frame_type;
434 enum uframe_modifier u_frame_modifier;
436 if (shdlc->rcv_q.qlen)
437 pr_debug("rcvQlen=%d\n", shdlc->rcv_q.qlen);
439 while ((skb = skb_dequeue(&shdlc->rcv_q)) != NULL) {
440 control = skb->data[0];
442 switch (control & SHDLC_CONTROL_HEAD_MASK) {
443 case SHDLC_CONTROL_HEAD_I:
444 case SHDLC_CONTROL_HEAD_I2:
445 ns = (control & SHDLC_CONTROL_NS_MASK) >> 3;
446 nr = control & SHDLC_CONTROL_NR_MASK;
447 nfc_shdlc_rcv_i_frame(shdlc, skb, ns, nr);
449 case SHDLC_CONTROL_HEAD_S:
450 s_frame_type = (control & SHDLC_CONTROL_TYPE_MASK) >> 3;
451 nr = control & SHDLC_CONTROL_NR_MASK;
452 nfc_shdlc_rcv_s_frame(shdlc, s_frame_type, nr);
455 case SHDLC_CONTROL_HEAD_U:
456 u_frame_modifier = control & SHDLC_CONTROL_M_MASK;
457 nfc_shdlc_rcv_u_frame(shdlc, skb, u_frame_modifier);
460 pr_err("UNKNOWN Control=%d\n", control);
467 static int nfc_shdlc_w_used(int ns, int dnr)
472 unack_count = ns - dnr;
474 unack_count = 8 - dnr + ns;
479 /* Send frames according to algorithm at spec:10.8.1 */
480 static void nfc_shdlc_handle_send_queue(struct nfc_shdlc *shdlc)
484 unsigned long time_sent;
486 if (shdlc->send_q.qlen)
488 ("sendQlen=%d ns=%d dnr=%d rnr=%s w_room=%d unackQlen=%d\n",
489 shdlc->send_q.qlen, shdlc->ns, shdlc->dnr,
490 shdlc->rnr == false ? "false" : "true",
491 shdlc->w - nfc_shdlc_w_used(shdlc->ns, shdlc->dnr),
492 shdlc->ack_pending_q.qlen);
494 while (shdlc->send_q.qlen && shdlc->ack_pending_q.qlen < shdlc->w &&
495 (shdlc->rnr == false)) {
497 if (shdlc->t1_active) {
498 del_timer_sync(&shdlc->t1_timer);
499 shdlc->t1_active = false;
500 pr_debug("Stopped T1(send ack)\n");
503 skb = skb_dequeue(&shdlc->send_q);
505 *skb_push(skb, 1) = SHDLC_CONTROL_HEAD_I | (shdlc->ns << 3) |
508 pr_debug("Sending I-Frame %d, waiting to rcv %d\n", shdlc->ns,
510 /* SHDLC_DUMP_SKB("shdlc frame written", skb); */
512 nfc_shdlc_add_len_crc(skb);
514 r = shdlc->ops->xmit(shdlc, skb);
516 shdlc->hard_fault = r;
520 shdlc->ns = (shdlc->ns + 1) % 8;
523 *(unsigned long *)skb->cb = time_sent;
525 skb_queue_tail(&shdlc->ack_pending_q, skb);
527 if (shdlc->t2_active == false) {
528 shdlc->t2_active = true;
529 mod_timer(&shdlc->t2_timer, time_sent +
530 msecs_to_jiffies(SHDLC_T2_VALUE_MS));
531 pr_debug("Started T2 (retransmit)\n");
536 static void nfc_shdlc_connect_timeout(unsigned long data)
538 struct nfc_shdlc *shdlc = (struct nfc_shdlc *)data;
542 queue_work(system_nrt_wq, &shdlc->sm_work);
545 static void nfc_shdlc_t1_timeout(unsigned long data)
547 struct nfc_shdlc *shdlc = (struct nfc_shdlc *)data;
549 pr_debug("SoftIRQ: need to send ack\n");
551 queue_work(system_nrt_wq, &shdlc->sm_work);
554 static void nfc_shdlc_t2_timeout(unsigned long data)
556 struct nfc_shdlc *shdlc = (struct nfc_shdlc *)data;
558 pr_debug("SoftIRQ: need to retransmit\n");
560 queue_work(system_nrt_wq, &shdlc->sm_work);
563 static void nfc_shdlc_sm_work(struct work_struct *work)
565 struct nfc_shdlc *shdlc = container_of(work, struct nfc_shdlc, sm_work);
570 mutex_lock(&shdlc->state_mutex);
572 switch (shdlc->state) {
573 case SHDLC_DISCONNECTED:
574 skb_queue_purge(&shdlc->rcv_q);
575 skb_queue_purge(&shdlc->send_q);
576 skb_queue_purge(&shdlc->ack_pending_q);
578 case SHDLC_CONNECTING:
579 if (shdlc->hard_fault) {
580 nfc_shdlc_connect_complete(shdlc, shdlc->hard_fault);
584 if (shdlc->connect_tries++ < 5)
585 r = nfc_shdlc_connect_initiate(shdlc);
589 nfc_shdlc_connect_complete(shdlc, r);
591 mod_timer(&shdlc->connect_timer, jiffies +
592 msecs_to_jiffies(SHDLC_CONNECT_VALUE_MS));
594 shdlc->state = SHDLC_NEGOCIATING;
597 case SHDLC_NEGOCIATING:
598 if (timer_pending(&shdlc->connect_timer) == 0) {
599 shdlc->state = SHDLC_CONNECTING;
600 queue_work(system_nrt_wq, &shdlc->sm_work);
603 nfc_shdlc_handle_rcv_queue(shdlc);
605 if (shdlc->hard_fault) {
606 nfc_shdlc_connect_complete(shdlc, shdlc->hard_fault);
610 case SHDLC_CONNECTED:
611 nfc_shdlc_handle_rcv_queue(shdlc);
612 nfc_shdlc_handle_send_queue(shdlc);
614 if (shdlc->t1_active && timer_pending(&shdlc->t1_timer) == 0) {
616 ("Handle T1(send ack) elapsed (T1 now inactive)\n");
618 shdlc->t1_active = false;
619 r = nfc_shdlc_send_s_frame(shdlc, S_FRAME_RR,
622 shdlc->hard_fault = r;
625 if (shdlc->t2_active && timer_pending(&shdlc->t2_timer) == 0) {
627 ("Handle T2(retransmit) elapsed (T2 inactive)\n");
629 shdlc->t2_active = false;
631 nfc_shdlc_requeue_ack_pending(shdlc);
632 nfc_shdlc_handle_send_queue(shdlc);
635 if (shdlc->hard_fault) {
636 nfc_hci_driver_failure(shdlc->hdev, shdlc->hard_fault);
642 mutex_unlock(&shdlc->state_mutex);
646 * Called from syscall context to establish shdlc link. Sleeps until
647 * link is ready or failure.
649 static int nfc_shdlc_connect(struct nfc_shdlc *shdlc)
651 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(connect_wq);
655 mutex_lock(&shdlc->state_mutex);
657 shdlc->state = SHDLC_CONNECTING;
658 shdlc->connect_wq = &connect_wq;
659 shdlc->connect_tries = 0;
660 shdlc->connect_result = 1;
662 mutex_unlock(&shdlc->state_mutex);
664 queue_work(system_nrt_wq, &shdlc->sm_work);
666 wait_event(connect_wq, shdlc->connect_result != 1);
668 return shdlc->connect_result;
671 static void nfc_shdlc_disconnect(struct nfc_shdlc *shdlc)
675 mutex_lock(&shdlc->state_mutex);
677 shdlc->state = SHDLC_DISCONNECTED;
679 mutex_unlock(&shdlc->state_mutex);
681 queue_work(system_nrt_wq, &shdlc->sm_work);
685 * Receive an incoming shdlc frame. Frame has already been crc-validated.
686 * skb contains only LLC header and payload.
687 * If skb == NULL, it is a notification that the link below is dead.
689 void nfc_shdlc_recv_frame(struct nfc_shdlc *shdlc, struct sk_buff *skb)
692 pr_err("NULL Frame -> link is dead\n");
693 shdlc->hard_fault = -EREMOTEIO;
695 SHDLC_DUMP_SKB("incoming frame", skb);
696 skb_queue_tail(&shdlc->rcv_q, skb);
699 queue_work(system_nrt_wq, &shdlc->sm_work);
701 EXPORT_SYMBOL(nfc_shdlc_recv_frame);
703 static int nfc_shdlc_open(struct nfc_hci_dev *hdev)
705 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
710 if (shdlc->ops->open) {
711 r = shdlc->ops->open(shdlc);
716 r = nfc_shdlc_connect(shdlc);
717 if (r < 0 && shdlc->ops->close)
718 shdlc->ops->close(shdlc);
723 static void nfc_shdlc_close(struct nfc_hci_dev *hdev)
725 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
729 nfc_shdlc_disconnect(shdlc);
731 if (shdlc->ops->close)
732 shdlc->ops->close(shdlc);
735 static int nfc_shdlc_hci_ready(struct nfc_hci_dev *hdev)
737 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
742 if (shdlc->ops->hci_ready)
743 r = shdlc->ops->hci_ready(shdlc);
748 static int nfc_shdlc_xmit(struct nfc_hci_dev *hdev, struct sk_buff *skb)
750 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
752 SHDLC_DUMP_SKB("queuing HCP packet to shdlc", skb);
754 skb_queue_tail(&shdlc->send_q, skb);
756 queue_work(system_nrt_wq, &shdlc->sm_work);
761 static int nfc_shdlc_start_poll(struct nfc_hci_dev *hdev,
762 u32 im_protocols, u32 tm_protocols)
764 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
768 if (shdlc->ops->start_poll)
769 return shdlc->ops->start_poll(shdlc,
770 im_protocols, tm_protocols);
775 static int nfc_shdlc_target_from_gate(struct nfc_hci_dev *hdev, u8 gate,
776 struct nfc_target *target)
778 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
780 if (shdlc->ops->target_from_gate)
781 return shdlc->ops->target_from_gate(shdlc, gate, target);
786 static int nfc_shdlc_complete_target_discovered(struct nfc_hci_dev *hdev,
788 struct nfc_target *target)
790 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
794 if (shdlc->ops->complete_target_discovered)
795 return shdlc->ops->complete_target_discovered(shdlc, gate,
801 static int nfc_shdlc_data_exchange(struct nfc_hci_dev *hdev,
802 struct nfc_target *target,
804 struct sk_buff **res_skb)
806 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
808 if (shdlc->ops->data_exchange)
809 return shdlc->ops->data_exchange(shdlc, target, skb, res_skb);
814 static int nfc_shdlc_check_presence(struct nfc_hci_dev *hdev,
815 struct nfc_target *target)
817 struct nfc_shdlc *shdlc = nfc_hci_get_clientdata(hdev);
819 if (shdlc->ops->check_presence)
820 return shdlc->ops->check_presence(shdlc, target);
825 static struct nfc_hci_ops shdlc_ops = {
826 .open = nfc_shdlc_open,
827 .close = nfc_shdlc_close,
828 .hci_ready = nfc_shdlc_hci_ready,
829 .xmit = nfc_shdlc_xmit,
830 .start_poll = nfc_shdlc_start_poll,
831 .target_from_gate = nfc_shdlc_target_from_gate,
832 .complete_target_discovered = nfc_shdlc_complete_target_discovered,
833 .data_exchange = nfc_shdlc_data_exchange,
834 .check_presence = nfc_shdlc_check_presence,
837 struct nfc_shdlc *nfc_shdlc_allocate(struct nfc_shdlc_ops *ops,
838 struct nfc_hci_init_data *init_data,
840 int tx_headroom, int tx_tailroom,
841 int max_link_payload, const char *devname)
843 struct nfc_shdlc *shdlc;
846 if (ops->xmit == NULL)
849 shdlc = kzalloc(sizeof(struct nfc_shdlc), GFP_KERNEL);
853 mutex_init(&shdlc->state_mutex);
855 shdlc->state = SHDLC_DISCONNECTED;
857 init_timer(&shdlc->connect_timer);
858 shdlc->connect_timer.data = (unsigned long)shdlc;
859 shdlc->connect_timer.function = nfc_shdlc_connect_timeout;
861 init_timer(&shdlc->t1_timer);
862 shdlc->t1_timer.data = (unsigned long)shdlc;
863 shdlc->t1_timer.function = nfc_shdlc_t1_timeout;
865 init_timer(&shdlc->t2_timer);
866 shdlc->t2_timer.data = (unsigned long)shdlc;
867 shdlc->t2_timer.function = nfc_shdlc_t2_timeout;
869 shdlc->w = SHDLC_MAX_WINDOW;
870 shdlc->srej_support = SHDLC_SREJ_SUPPORT;
872 skb_queue_head_init(&shdlc->rcv_q);
873 skb_queue_head_init(&shdlc->send_q);
874 skb_queue_head_init(&shdlc->ack_pending_q);
876 INIT_WORK(&shdlc->sm_work, nfc_shdlc_sm_work);
878 shdlc->client_headroom = tx_headroom;
879 shdlc->client_tailroom = tx_tailroom;
881 shdlc->hdev = nfc_hci_allocate_device(&shdlc_ops, init_data, protocols,
882 tx_headroom + SHDLC_LLC_HEAD_ROOM,
883 tx_tailroom + SHDLC_LLC_TAIL_ROOM,
885 if (shdlc->hdev == NULL)
888 nfc_hci_set_clientdata(shdlc->hdev, shdlc);
890 r = nfc_hci_register_device(shdlc->hdev);
897 nfc_hci_free_device(shdlc->hdev);
904 EXPORT_SYMBOL(nfc_shdlc_allocate);
906 void nfc_shdlc_free(struct nfc_shdlc *shdlc)
910 nfc_hci_unregister_device(shdlc->hdev);
911 nfc_hci_free_device(shdlc->hdev);
913 cancel_work_sync(&shdlc->sm_work);
915 skb_queue_purge(&shdlc->rcv_q);
916 skb_queue_purge(&shdlc->send_q);
917 skb_queue_purge(&shdlc->ack_pending_q);
921 EXPORT_SYMBOL(nfc_shdlc_free);
923 void nfc_shdlc_set_clientdata(struct nfc_shdlc *shdlc, void *clientdata)
927 shdlc->clientdata = clientdata;
929 EXPORT_SYMBOL(nfc_shdlc_set_clientdata);
931 void *nfc_shdlc_get_clientdata(struct nfc_shdlc *shdlc)
933 return shdlc->clientdata;
935 EXPORT_SYMBOL(nfc_shdlc_get_clientdata);
937 struct nfc_hci_dev *nfc_shdlc_get_hci_dev(struct nfc_shdlc *shdlc)
941 EXPORT_SYMBOL(nfc_shdlc_get_hci_dev);