2 HIDP implementation for Linux Bluetooth stack (BlueZ).
3 Copyright (C) 2003-2004 Marcel Holtmann <marcel@holtmann.org>
4 Copyright (C) 2013 David Herrmann <dh.herrmann@gmail.com>
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License version 2 as
8 published by the Free Software Foundation;
10 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
11 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
12 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
13 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
14 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
15 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
20 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
21 SOFTWARE IS DISCLAIMED.
24 #include <linux/kref.h>
25 #include <linux/module.h>
26 #include <linux/file.h>
27 #include <linux/kthread.h>
28 #include <linux/hidraw.h>
30 #include <net/bluetooth/bluetooth.h>
31 #include <net/bluetooth/hci_core.h>
32 #include <net/bluetooth/l2cap.h>
38 static DECLARE_RWSEM(hidp_session_sem);
39 static DECLARE_WAIT_QUEUE_HEAD(hidp_session_wq);
40 static LIST_HEAD(hidp_session_list);
42 static unsigned char hidp_keycode[256] = {
43 0, 0, 0, 0, 30, 48, 46, 32, 18, 33, 34, 35, 23, 36,
44 37, 38, 50, 49, 24, 25, 16, 19, 31, 20, 22, 47, 17, 45,
45 21, 44, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 28, 1,
46 14, 15, 57, 12, 13, 26, 27, 43, 43, 39, 40, 41, 51, 52,
47 53, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 87, 88,
48 99, 70, 119, 110, 102, 104, 111, 107, 109, 106, 105, 108, 103, 69,
49 98, 55, 74, 78, 96, 79, 80, 81, 75, 76, 77, 71, 72, 73,
50 82, 83, 86, 127, 116, 117, 183, 184, 185, 186, 187, 188, 189, 190,
51 191, 192, 193, 194, 134, 138, 130, 132, 128, 129, 131, 137, 133, 135,
52 136, 113, 115, 114, 0, 0, 0, 121, 0, 89, 93, 124, 92, 94,
53 95, 0, 0, 0, 122, 123, 90, 91, 85, 0, 0, 0, 0, 0,
54 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
55 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
56 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
57 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
58 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
59 29, 42, 56, 125, 97, 54, 100, 126, 164, 166, 165, 163, 161, 115,
60 114, 113, 150, 158, 159, 128, 136, 177, 178, 176, 142, 152, 173, 140
63 static unsigned char hidp_mkeyspat[] = { 0x01, 0x01, 0x01, 0x01, 0x01, 0x01 };
65 static int hidp_session_probe(struct l2cap_conn *conn,
66 struct l2cap_user *user);
67 static void hidp_session_remove(struct l2cap_conn *conn,
68 struct l2cap_user *user);
69 static int hidp_session_thread(void *arg);
70 static void hidp_session_terminate(struct hidp_session *s);
72 static void hidp_copy_session(struct hidp_session *session, struct hidp_conninfo *ci)
75 memset(ci, 0, sizeof(*ci));
76 bacpy(&ci->bdaddr, &session->bdaddr);
78 ci->flags = session->flags & valid_flags;
79 ci->state = BT_CONNECTED;
82 ci->vendor = session->input->id.vendor;
83 ci->product = session->input->id.product;
84 ci->version = session->input->id.version;
85 if (session->input->name)
86 strscpy(ci->name, session->input->name, 128);
88 strscpy(ci->name, "HID Boot Device", 128);
89 } else if (session->hid) {
90 ci->vendor = session->hid->vendor;
91 ci->product = session->hid->product;
92 ci->version = session->hid->version;
93 strscpy(ci->name, session->hid->name, 128);
97 /* assemble skb, queue message on @transmit and wake up the session thread */
98 static int hidp_send_message(struct hidp_session *session, struct socket *sock,
99 struct sk_buff_head *transmit, unsigned char hdr,
100 const unsigned char *data, int size)
103 struct sock *sk = sock->sk;
106 BT_DBG("session %p data %p size %d", session, data, size);
108 if (atomic_read(&session->terminate))
111 skb = alloc_skb(size + 1, GFP_ATOMIC);
113 BT_ERR("Can't allocate memory for new frame");
117 skb_put_u8(skb, hdr);
118 if (data && size > 0) {
119 skb_put_data(skb, data, size);
125 skb_queue_tail(transmit, skb);
126 wake_up_interruptible(sk_sleep(sk));
131 static int hidp_send_ctrl_message(struct hidp_session *session,
132 unsigned char hdr, const unsigned char *data,
135 return hidp_send_message(session, session->ctrl_sock,
136 &session->ctrl_transmit, hdr, data, size);
139 static int hidp_send_intr_message(struct hidp_session *session,
140 unsigned char hdr, const unsigned char *data,
143 return hidp_send_message(session, session->intr_sock,
144 &session->intr_transmit, hdr, data, size);
147 static int hidp_input_event(struct input_dev *dev, unsigned int type,
148 unsigned int code, int value)
150 struct hidp_session *session = input_get_drvdata(dev);
151 unsigned char newleds;
152 unsigned char hdr, data[2];
154 BT_DBG("session %p type %d code %d value %d",
155 session, type, code, value);
160 newleds = (!!test_bit(LED_KANA, dev->led) << 3) |
161 (!!test_bit(LED_COMPOSE, dev->led) << 3) |
162 (!!test_bit(LED_SCROLLL, dev->led) << 2) |
163 (!!test_bit(LED_CAPSL, dev->led) << 1) |
164 (!!test_bit(LED_NUML, dev->led) << 0);
166 if (session->leds == newleds)
169 session->leds = newleds;
171 hdr = HIDP_TRANS_DATA | HIDP_DATA_RTYPE_OUPUT;
175 return hidp_send_intr_message(session, hdr, data, 2);
178 static void hidp_input_report(struct hidp_session *session, struct sk_buff *skb)
180 struct input_dev *dev = session->input;
181 unsigned char *keys = session->keys;
182 unsigned char *udata = skb->data + 1;
183 signed char *sdata = skb->data + 1;
184 int i, size = skb->len - 1;
186 switch (skb->data[0]) {
187 case 0x01: /* Keyboard report */
188 for (i = 0; i < 8; i++)
189 input_report_key(dev, hidp_keycode[i + 224], (udata[0] >> i) & 1);
191 /* If all the key codes have been set to 0x01, it means
192 * too many keys were pressed at the same time. */
193 if (!memcmp(udata + 2, hidp_mkeyspat, 6))
196 for (i = 2; i < 8; i++) {
197 if (keys[i] > 3 && memscan(udata + 2, keys[i], 6) == udata + 8) {
198 if (hidp_keycode[keys[i]])
199 input_report_key(dev, hidp_keycode[keys[i]], 0);
201 BT_ERR("Unknown key (scancode %#x) released.", keys[i]);
204 if (udata[i] > 3 && memscan(keys + 2, udata[i], 6) == keys + 8) {
205 if (hidp_keycode[udata[i]])
206 input_report_key(dev, hidp_keycode[udata[i]], 1);
208 BT_ERR("Unknown key (scancode %#x) pressed.", udata[i]);
212 memcpy(keys, udata, 8);
215 case 0x02: /* Mouse report */
216 input_report_key(dev, BTN_LEFT, sdata[0] & 0x01);
217 input_report_key(dev, BTN_RIGHT, sdata[0] & 0x02);
218 input_report_key(dev, BTN_MIDDLE, sdata[0] & 0x04);
219 input_report_key(dev, BTN_SIDE, sdata[0] & 0x08);
220 input_report_key(dev, BTN_EXTRA, sdata[0] & 0x10);
222 input_report_rel(dev, REL_X, sdata[1]);
223 input_report_rel(dev, REL_Y, sdata[2]);
226 input_report_rel(dev, REL_WHEEL, sdata[3]);
233 static int hidp_get_raw_report(struct hid_device *hid,
234 unsigned char report_number,
235 unsigned char *data, size_t count,
236 unsigned char report_type)
238 struct hidp_session *session = hid->driver_data;
241 int numbered_reports = hid->report_enum[report_type].numbered;
244 if (atomic_read(&session->terminate))
247 switch (report_type) {
248 case HID_FEATURE_REPORT:
249 report_type = HIDP_TRANS_GET_REPORT | HIDP_DATA_RTYPE_FEATURE;
251 case HID_INPUT_REPORT:
252 report_type = HIDP_TRANS_GET_REPORT | HIDP_DATA_RTYPE_INPUT;
254 case HID_OUTPUT_REPORT:
255 report_type = HIDP_TRANS_GET_REPORT | HIDP_DATA_RTYPE_OUPUT;
261 if (mutex_lock_interruptible(&session->report_mutex))
264 /* Set up our wait, and send the report request to the device. */
265 session->waiting_report_type = report_type & HIDP_DATA_RTYPE_MASK;
266 session->waiting_report_number = numbered_reports ? report_number : -1;
267 set_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
268 data[0] = report_number;
269 ret = hidp_send_ctrl_message(session, report_type, data, 1);
273 /* Wait for the return of the report. The returned report
274 gets put in session->report_return. */
275 while (test_bit(HIDP_WAITING_FOR_RETURN, &session->flags) &&
276 !atomic_read(&session->terminate)) {
279 res = wait_event_interruptible_timeout(session->report_queue,
280 !test_bit(HIDP_WAITING_FOR_RETURN, &session->flags)
281 || atomic_read(&session->terminate),
295 skb = session->report_return;
297 len = skb->len < count ? skb->len : count;
298 memcpy(data, skb->data, len);
301 session->report_return = NULL;
303 /* Device returned a HANDSHAKE, indicating protocol error. */
307 clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
308 mutex_unlock(&session->report_mutex);
313 clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
314 mutex_unlock(&session->report_mutex);
318 static int hidp_set_raw_report(struct hid_device *hid, unsigned char reportnum,
319 unsigned char *data, size_t count,
320 unsigned char report_type)
322 struct hidp_session *session = hid->driver_data;
325 switch (report_type) {
326 case HID_FEATURE_REPORT:
327 report_type = HIDP_TRANS_SET_REPORT | HIDP_DATA_RTYPE_FEATURE;
329 case HID_INPUT_REPORT:
330 report_type = HIDP_TRANS_SET_REPORT | HIDP_DATA_RTYPE_INPUT;
332 case HID_OUTPUT_REPORT:
333 report_type = HIDP_TRANS_SET_REPORT | HIDP_DATA_RTYPE_OUPUT;
339 if (mutex_lock_interruptible(&session->report_mutex))
342 /* Set up our wait, and send the report request to the device. */
344 set_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags);
345 ret = hidp_send_ctrl_message(session, report_type, data, count);
349 /* Wait for the ACK from the device. */
350 while (test_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags) &&
351 !atomic_read(&session->terminate)) {
354 res = wait_event_interruptible_timeout(session->report_queue,
355 !test_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags)
356 || atomic_read(&session->terminate),
370 if (!session->output_report_success) {
378 clear_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags);
379 mutex_unlock(&session->report_mutex);
383 static int hidp_output_report(struct hid_device *hid, __u8 *data, size_t count)
385 struct hidp_session *session = hid->driver_data;
387 return hidp_send_intr_message(session,
388 HIDP_TRANS_DATA | HIDP_DATA_RTYPE_OUPUT,
392 static int hidp_raw_request(struct hid_device *hid, unsigned char reportnum,
393 __u8 *buf, size_t len, unsigned char rtype,
397 case HID_REQ_GET_REPORT:
398 return hidp_get_raw_report(hid, reportnum, buf, len, rtype);
399 case HID_REQ_SET_REPORT:
400 return hidp_set_raw_report(hid, reportnum, buf, len, rtype);
406 static void hidp_idle_timeout(struct timer_list *t)
408 struct hidp_session *session = from_timer(session, t, timer);
410 /* The HIDP user-space API only contains calls to add and remove
411 * devices. There is no way to forward events of any kind. Therefore,
412 * we have to forcefully disconnect a device on idle-timeouts. This is
413 * unfortunate and weird API design, but it is spec-compliant and
414 * required for backwards-compatibility. Hence, on idle-timeout, we
415 * signal driver-detach events, so poll() will be woken up with an
416 * error-condition on both sockets.
419 session->intr_sock->sk->sk_err = EUNATCH;
420 session->ctrl_sock->sk->sk_err = EUNATCH;
421 wake_up_interruptible(sk_sleep(session->intr_sock->sk));
422 wake_up_interruptible(sk_sleep(session->ctrl_sock->sk));
424 hidp_session_terminate(session);
427 static void hidp_set_timer(struct hidp_session *session)
429 if (session->idle_to > 0)
430 mod_timer(&session->timer, jiffies + HZ * session->idle_to);
433 static void hidp_del_timer(struct hidp_session *session)
435 if (session->idle_to > 0)
436 del_timer_sync(&session->timer);
439 static void hidp_process_report(struct hidp_session *session, int type,
440 const u8 *data, unsigned int len, int intr)
442 if (len > HID_MAX_BUFFER_SIZE)
443 len = HID_MAX_BUFFER_SIZE;
445 memcpy(session->input_buf, data, len);
446 hid_input_report(session->hid, type, session->input_buf, len, intr);
449 static void hidp_process_handshake(struct hidp_session *session,
452 BT_DBG("session %p param 0x%02x", session, param);
453 session->output_report_success = 0; /* default condition */
456 case HIDP_HSHK_SUCCESSFUL:
457 /* FIXME: Call into SET_ GET_ handlers here */
458 session->output_report_success = 1;
461 case HIDP_HSHK_NOT_READY:
462 case HIDP_HSHK_ERR_INVALID_REPORT_ID:
463 case HIDP_HSHK_ERR_UNSUPPORTED_REQUEST:
464 case HIDP_HSHK_ERR_INVALID_PARAMETER:
465 if (test_and_clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags))
466 wake_up_interruptible(&session->report_queue);
468 /* FIXME: Call into SET_ GET_ handlers here */
471 case HIDP_HSHK_ERR_UNKNOWN:
474 case HIDP_HSHK_ERR_FATAL:
475 /* Device requests a reboot, as this is the only way this error
476 * can be recovered. */
477 hidp_send_ctrl_message(session,
478 HIDP_TRANS_HID_CONTROL | HIDP_CTRL_SOFT_RESET, NULL, 0);
482 hidp_send_ctrl_message(session,
483 HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
487 /* Wake up the waiting thread. */
488 if (test_and_clear_bit(HIDP_WAITING_FOR_SEND_ACK, &session->flags))
489 wake_up_interruptible(&session->report_queue);
492 static void hidp_process_hid_control(struct hidp_session *session,
495 BT_DBG("session %p param 0x%02x", session, param);
497 if (param == HIDP_CTRL_VIRTUAL_CABLE_UNPLUG) {
498 /* Flush the transmit queues */
499 skb_queue_purge(&session->ctrl_transmit);
500 skb_queue_purge(&session->intr_transmit);
502 hidp_session_terminate(session);
506 /* Returns true if the passed-in skb should be freed by the caller. */
507 static int hidp_process_data(struct hidp_session *session, struct sk_buff *skb,
510 int done_with_skb = 1;
511 BT_DBG("session %p skb %p len %u param 0x%02x", session, skb, skb->len, param);
514 case HIDP_DATA_RTYPE_INPUT:
515 hidp_set_timer(session);
518 hidp_input_report(session, skb);
521 hidp_process_report(session, HID_INPUT_REPORT,
522 skb->data, skb->len, 0);
525 case HIDP_DATA_RTYPE_OTHER:
526 case HIDP_DATA_RTYPE_OUPUT:
527 case HIDP_DATA_RTYPE_FEATURE:
531 hidp_send_ctrl_message(session,
532 HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_INVALID_PARAMETER, NULL, 0);
535 if (test_bit(HIDP_WAITING_FOR_RETURN, &session->flags) &&
536 param == session->waiting_report_type) {
537 if (session->waiting_report_number < 0 ||
538 session->waiting_report_number == skb->data[0]) {
539 /* hidp_get_raw_report() is waiting on this report. */
540 session->report_return = skb;
542 clear_bit(HIDP_WAITING_FOR_RETURN, &session->flags);
543 wake_up_interruptible(&session->report_queue);
547 return done_with_skb;
550 static void hidp_recv_ctrl_frame(struct hidp_session *session,
553 unsigned char hdr, type, param;
556 BT_DBG("session %p skb %p len %u", session, skb, skb->len);
561 type = hdr & HIDP_HEADER_TRANS_MASK;
562 param = hdr & HIDP_HEADER_PARAM_MASK;
565 case HIDP_TRANS_HANDSHAKE:
566 hidp_process_handshake(session, param);
569 case HIDP_TRANS_HID_CONTROL:
570 hidp_process_hid_control(session, param);
573 case HIDP_TRANS_DATA:
574 free_skb = hidp_process_data(session, skb, param);
578 hidp_send_ctrl_message(session,
579 HIDP_TRANS_HANDSHAKE | HIDP_HSHK_ERR_UNSUPPORTED_REQUEST, NULL, 0);
587 static void hidp_recv_intr_frame(struct hidp_session *session,
592 BT_DBG("session %p skb %p len %u", session, skb, skb->len);
597 if (hdr == (HIDP_TRANS_DATA | HIDP_DATA_RTYPE_INPUT)) {
598 hidp_set_timer(session);
601 hidp_input_report(session, skb);
604 hidp_process_report(session, HID_INPUT_REPORT,
605 skb->data, skb->len, 1);
606 BT_DBG("report len %d", skb->len);
609 BT_DBG("Unsupported protocol header 0x%02x", hdr);
615 static int hidp_send_frame(struct socket *sock, unsigned char *data, int len)
617 struct kvec iv = { data, len };
620 BT_DBG("sock %p data %p len %d", sock, data, len);
625 memset(&msg, 0, sizeof(msg));
627 return kernel_sendmsg(sock, &msg, &iv, 1, len);
630 /* dequeue message from @transmit and send via @sock */
631 static void hidp_process_transmit(struct hidp_session *session,
632 struct sk_buff_head *transmit,
638 BT_DBG("session %p", session);
640 while ((skb = skb_dequeue(transmit))) {
641 ret = hidp_send_frame(sock, skb->data, skb->len);
642 if (ret == -EAGAIN) {
643 skb_queue_head(transmit, skb);
645 } else if (ret < 0) {
646 hidp_session_terminate(session);
651 hidp_set_timer(session);
656 static int hidp_setup_input(struct hidp_session *session,
657 const struct hidp_connadd_req *req)
659 struct input_dev *input;
662 input = input_allocate_device();
666 session->input = input;
668 input_set_drvdata(input, session);
670 input->name = "Bluetooth HID Boot Protocol Device";
672 input->id.bustype = BUS_BLUETOOTH;
673 input->id.vendor = req->vendor;
674 input->id.product = req->product;
675 input->id.version = req->version;
677 if (req->subclass & 0x40) {
678 set_bit(EV_KEY, input->evbit);
679 set_bit(EV_LED, input->evbit);
680 set_bit(EV_REP, input->evbit);
682 set_bit(LED_NUML, input->ledbit);
683 set_bit(LED_CAPSL, input->ledbit);
684 set_bit(LED_SCROLLL, input->ledbit);
685 set_bit(LED_COMPOSE, input->ledbit);
686 set_bit(LED_KANA, input->ledbit);
688 for (i = 0; i < sizeof(hidp_keycode); i++)
689 set_bit(hidp_keycode[i], input->keybit);
690 clear_bit(0, input->keybit);
693 if (req->subclass & 0x80) {
694 input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL);
695 input->keybit[BIT_WORD(BTN_MOUSE)] = BIT_MASK(BTN_LEFT) |
696 BIT_MASK(BTN_RIGHT) | BIT_MASK(BTN_MIDDLE);
697 input->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y);
698 input->keybit[BIT_WORD(BTN_MOUSE)] |= BIT_MASK(BTN_SIDE) |
700 input->relbit[0] |= BIT_MASK(REL_WHEEL);
703 input->dev.parent = &session->conn->hcon->dev;
705 input->event = hidp_input_event;
710 static int hidp_open(struct hid_device *hid)
715 static void hidp_close(struct hid_device *hid)
719 static int hidp_parse(struct hid_device *hid)
721 struct hidp_session *session = hid->driver_data;
723 return hid_parse_report(session->hid, session->rd_data,
727 static int hidp_start(struct hid_device *hid)
732 static void hidp_stop(struct hid_device *hid)
734 struct hidp_session *session = hid->driver_data;
736 skb_queue_purge(&session->ctrl_transmit);
737 skb_queue_purge(&session->intr_transmit);
742 static const struct hid_ll_driver hidp_hid_driver = {
748 .raw_request = hidp_raw_request,
749 .output_report = hidp_output_report,
752 /* This function sets up the hid device. It does not add it
753 to the HID system. That is done in hidp_add_connection(). */
754 static int hidp_setup_hid(struct hidp_session *session,
755 const struct hidp_connadd_req *req)
757 struct hid_device *hid;
760 session->rd_data = memdup_user(req->rd_data, req->rd_size);
761 if (IS_ERR(session->rd_data))
762 return PTR_ERR(session->rd_data);
764 session->rd_size = req->rd_size;
766 hid = hid_allocate_device();
774 hid->driver_data = session;
776 hid->bus = BUS_BLUETOOTH;
777 hid->vendor = req->vendor;
778 hid->product = req->product;
779 hid->version = req->version;
780 hid->country = req->country;
782 strscpy(hid->name, req->name, sizeof(hid->name));
784 snprintf(hid->phys, sizeof(hid->phys), "%pMR",
785 &l2cap_pi(session->ctrl_sock->sk)->chan->src);
787 /* NOTE: Some device modules depend on the dst address being stored in
788 * uniq. Please be aware of this before making changes to this behavior.
790 snprintf(hid->uniq, sizeof(hid->uniq), "%pMR",
791 &l2cap_pi(session->ctrl_sock->sk)->chan->dst);
793 hid->dev.parent = &session->conn->hcon->dev;
794 hid->ll_driver = &hidp_hid_driver;
796 /* True if device is blocked in drivers/hid/hid-quirks.c */
797 if (hid_ignore(hid)) {
798 hid_destroy_device(session->hid);
806 kfree(session->rd_data);
807 session->rd_data = NULL;
812 /* initialize session devices */
813 static int hidp_session_dev_init(struct hidp_session *session,
814 const struct hidp_connadd_req *req)
818 if (req->rd_size > 0) {
819 ret = hidp_setup_hid(session, req);
820 if (ret && ret != -ENODEV)
825 ret = hidp_setup_input(session, req);
833 /* destroy session devices */
834 static void hidp_session_dev_destroy(struct hidp_session *session)
837 put_device(&session->hid->dev);
838 else if (session->input)
839 input_put_device(session->input);
841 kfree(session->rd_data);
842 session->rd_data = NULL;
845 /* add HID/input devices to their underlying bus systems */
846 static int hidp_session_dev_add(struct hidp_session *session)
850 /* Both HID and input systems drop a ref-count when unregistering the
851 * device but they don't take a ref-count when registering them. Work
852 * around this by explicitly taking a refcount during registration
853 * which is dropped automatically by unregistering the devices. */
856 ret = hid_add_device(session->hid);
859 get_device(&session->hid->dev);
860 } else if (session->input) {
861 ret = input_register_device(session->input);
864 input_get_device(session->input);
870 /* remove HID/input devices from their bus systems */
871 static void hidp_session_dev_del(struct hidp_session *session)
874 hid_destroy_device(session->hid);
875 else if (session->input)
876 input_unregister_device(session->input);
880 * Asynchronous device registration
881 * HID device drivers might want to perform I/O during initialization to
882 * detect device types. Therefore, call device registration in a separate
883 * worker so the HIDP thread can schedule I/O operations.
884 * Note that this must be called after the worker thread was initialized
885 * successfully. This will then add the devices and increase session state
886 * on success, otherwise it will terminate the session thread.
888 static void hidp_session_dev_work(struct work_struct *work)
890 struct hidp_session *session = container_of(work,
895 ret = hidp_session_dev_add(session);
897 atomic_inc(&session->state);
899 hidp_session_terminate(session);
903 * Create new session object
904 * Allocate session object, initialize static fields, copy input data into the
905 * object and take a reference to all sub-objects.
906 * This returns 0 on success and puts a pointer to the new session object in
907 * \out. Otherwise, an error code is returned.
908 * The new session object has an initial ref-count of 1.
910 static int hidp_session_new(struct hidp_session **out, const bdaddr_t *bdaddr,
911 struct socket *ctrl_sock,
912 struct socket *intr_sock,
913 const struct hidp_connadd_req *req,
914 struct l2cap_conn *conn)
916 struct hidp_session *session;
918 struct bt_sock *ctrl, *intr;
920 ctrl = bt_sk(ctrl_sock->sk);
921 intr = bt_sk(intr_sock->sk);
923 session = kzalloc(sizeof(*session), GFP_KERNEL);
927 /* object and runtime management */
928 kref_init(&session->ref);
929 atomic_set(&session->state, HIDP_SESSION_IDLING);
930 init_waitqueue_head(&session->state_queue);
931 session->flags = req->flags & BIT(HIDP_BLUETOOTH_VENDOR_ID);
933 /* connection management */
934 bacpy(&session->bdaddr, bdaddr);
935 session->conn = l2cap_conn_get(conn);
936 session->user.probe = hidp_session_probe;
937 session->user.remove = hidp_session_remove;
938 INIT_LIST_HEAD(&session->user.list);
939 session->ctrl_sock = ctrl_sock;
940 session->intr_sock = intr_sock;
941 skb_queue_head_init(&session->ctrl_transmit);
942 skb_queue_head_init(&session->intr_transmit);
943 session->ctrl_mtu = min_t(uint, l2cap_pi(ctrl)->chan->omtu,
944 l2cap_pi(ctrl)->chan->imtu);
945 session->intr_mtu = min_t(uint, l2cap_pi(intr)->chan->omtu,
946 l2cap_pi(intr)->chan->imtu);
947 session->idle_to = req->idle_to;
949 /* device management */
950 INIT_WORK(&session->dev_init, hidp_session_dev_work);
951 timer_setup(&session->timer, hidp_idle_timeout, 0);
954 mutex_init(&session->report_mutex);
955 init_waitqueue_head(&session->report_queue);
957 ret = hidp_session_dev_init(session, req);
961 get_file(session->intr_sock->file);
962 get_file(session->ctrl_sock->file);
967 l2cap_conn_put(session->conn);
972 /* increase ref-count of the given session by one */
973 static void hidp_session_get(struct hidp_session *session)
975 kref_get(&session->ref);
978 /* release callback */
979 static void session_free(struct kref *ref)
981 struct hidp_session *session = container_of(ref, struct hidp_session,
984 hidp_session_dev_destroy(session);
985 skb_queue_purge(&session->ctrl_transmit);
986 skb_queue_purge(&session->intr_transmit);
987 fput(session->intr_sock->file);
988 fput(session->ctrl_sock->file);
989 l2cap_conn_put(session->conn);
993 /* decrease ref-count of the given session by one */
994 static void hidp_session_put(struct hidp_session *session)
996 kref_put(&session->ref, session_free);
1000 * Search the list of active sessions for a session with target address
1001 * \bdaddr. You must hold at least a read-lock on \hidp_session_sem. As long as
1002 * you do not release this lock, the session objects cannot vanish and you can
1003 * safely take a reference to the session yourself.
1005 static struct hidp_session *__hidp_session_find(const bdaddr_t *bdaddr)
1007 struct hidp_session *session;
1009 list_for_each_entry(session, &hidp_session_list, list) {
1010 if (!bacmp(bdaddr, &session->bdaddr))
1018 * Same as __hidp_session_find() but no locks must be held. This also takes a
1019 * reference of the returned session (if non-NULL) so you must drop this
1020 * reference if you no longer use the object.
1022 static struct hidp_session *hidp_session_find(const bdaddr_t *bdaddr)
1024 struct hidp_session *session;
1026 down_read(&hidp_session_sem);
1028 session = __hidp_session_find(bdaddr);
1030 hidp_session_get(session);
1032 up_read(&hidp_session_sem);
1038 * Start session synchronously
1039 * This starts a session thread and waits until initialization
1040 * is done or returns an error if it couldn't be started.
1041 * If this returns 0 the session thread is up and running. You must call
1042 * hipd_session_stop_sync() before deleting any runtime resources.
1044 static int hidp_session_start_sync(struct hidp_session *session)
1046 unsigned int vendor, product;
1049 vendor = session->hid->vendor;
1050 product = session->hid->product;
1051 } else if (session->input) {
1052 vendor = session->input->id.vendor;
1053 product = session->input->id.product;
1059 session->task = kthread_run(hidp_session_thread, session,
1060 "khidpd_%04x%04x", vendor, product);
1061 if (IS_ERR(session->task))
1062 return PTR_ERR(session->task);
1064 while (atomic_read(&session->state) <= HIDP_SESSION_IDLING)
1065 wait_event(session->state_queue,
1066 atomic_read(&session->state) > HIDP_SESSION_IDLING);
1072 * Terminate session thread
1073 * Wake up session thread and notify it to stop. This is asynchronous and
1074 * returns immediately. Call this whenever a runtime error occurs and you want
1075 * the session to stop.
1076 * Note: wake_up_interruptible() performs any necessary memory-barriers for us.
1078 static void hidp_session_terminate(struct hidp_session *session)
1080 atomic_inc(&session->terminate);
1082 * See the comment preceding the call to wait_woken()
1083 * in hidp_session_run().
1085 wake_up_interruptible(&hidp_session_wq);
1089 * Probe HIDP session
1090 * This is called from the l2cap_conn core when our l2cap_user object is bound
1091 * to the hci-connection. We get the session via the \user object and can now
1092 * start the session thread, link it into the global session list and
1093 * schedule HID/input device registration.
1094 * The global session-list owns its own reference to the session object so you
1095 * can drop your own reference after registering the l2cap_user object.
1097 static int hidp_session_probe(struct l2cap_conn *conn,
1098 struct l2cap_user *user)
1100 struct hidp_session *session = container_of(user,
1101 struct hidp_session,
1103 struct hidp_session *s;
1106 down_write(&hidp_session_sem);
1108 /* check that no other session for this device exists */
1109 s = __hidp_session_find(&session->bdaddr);
1115 if (session->input) {
1116 ret = hidp_session_dev_add(session);
1121 ret = hidp_session_start_sync(session);
1125 /* HID device registration is async to allow I/O during probe */
1127 atomic_inc(&session->state);
1129 schedule_work(&session->dev_init);
1131 hidp_session_get(session);
1132 list_add(&session->list, &hidp_session_list);
1138 hidp_session_dev_del(session);
1140 up_write(&hidp_session_sem);
1145 * Remove HIDP session
1146 * Called from the l2cap_conn core when either we explicitly unregistered
1147 * the l2cap_user object or if the underlying connection is shut down.
1148 * We signal the hidp-session thread to shut down, unregister the HID/input
1149 * devices and unlink the session from the global list.
1150 * This drops the reference to the session that is owned by the global
1152 * Note: We _must_ not synchronosly wait for the session-thread to shut down.
1153 * This is, because the session-thread might be waiting for an HCI lock that is
1154 * held while we are called. Therefore, we only unregister the devices and
1155 * notify the session-thread to terminate. The thread itself owns a reference
1156 * to the session object so it can safely shut down.
1158 static void hidp_session_remove(struct l2cap_conn *conn,
1159 struct l2cap_user *user)
1161 struct hidp_session *session = container_of(user,
1162 struct hidp_session,
1165 down_write(&hidp_session_sem);
1167 hidp_session_terminate(session);
1169 cancel_work_sync(&session->dev_init);
1170 if (session->input ||
1171 atomic_read(&session->state) > HIDP_SESSION_PREPARING)
1172 hidp_session_dev_del(session);
1174 list_del(&session->list);
1176 up_write(&hidp_session_sem);
1178 hidp_session_put(session);
1183 * This performs the actual main-loop of the HIDP worker. We first check
1184 * whether the underlying connection is still alive, then parse all pending
1185 * messages and finally send all outstanding messages.
1187 static void hidp_session_run(struct hidp_session *session)
1189 struct sock *ctrl_sk = session->ctrl_sock->sk;
1190 struct sock *intr_sk = session->intr_sock->sk;
1191 struct sk_buff *skb;
1192 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1194 add_wait_queue(&hidp_session_wq, &wait);
1197 * This thread can be woken up two ways:
1198 * - You call hidp_session_terminate() which sets the
1199 * session->terminate flag and wakes this thread up.
1200 * - Via modifying the socket state of ctrl/intr_sock. This
1201 * thread is woken up by ->sk_state_changed().
1204 if (atomic_read(&session->terminate))
1207 if (ctrl_sk->sk_state != BT_CONNECTED ||
1208 intr_sk->sk_state != BT_CONNECTED)
1211 /* parse incoming intr-skbs */
1212 while ((skb = skb_dequeue(&intr_sk->sk_receive_queue))) {
1214 if (!skb_linearize(skb))
1215 hidp_recv_intr_frame(session, skb);
1220 /* send pending intr-skbs */
1221 hidp_process_transmit(session, &session->intr_transmit,
1222 session->intr_sock);
1224 /* parse incoming ctrl-skbs */
1225 while ((skb = skb_dequeue(&ctrl_sk->sk_receive_queue))) {
1227 if (!skb_linearize(skb))
1228 hidp_recv_ctrl_frame(session, skb);
1233 /* send pending ctrl-skbs */
1234 hidp_process_transmit(session, &session->ctrl_transmit,
1235 session->ctrl_sock);
1238 * wait_woken() performs the necessary memory barriers
1239 * for us; see the header comment for this primitive.
1241 wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
1243 remove_wait_queue(&hidp_session_wq, &wait);
1245 atomic_inc(&session->terminate);
1248 static int hidp_session_wake_function(wait_queue_entry_t *wait,
1250 int sync, void *key)
1252 wake_up_interruptible(&hidp_session_wq);
1257 * HIDP session thread
1258 * This thread runs the I/O for a single HIDP session. Startup is synchronous
1259 * which allows us to take references to ourself here instead of doing that in
1261 * When we are ready to run we notify the caller and call hidp_session_run().
1263 static int hidp_session_thread(void *arg)
1265 struct hidp_session *session = arg;
1266 DEFINE_WAIT_FUNC(ctrl_wait, hidp_session_wake_function);
1267 DEFINE_WAIT_FUNC(intr_wait, hidp_session_wake_function);
1269 BT_DBG("session %p", session);
1271 /* initialize runtime environment */
1272 hidp_session_get(session);
1273 __module_get(THIS_MODULE);
1274 set_user_nice(current, -15);
1275 hidp_set_timer(session);
1277 add_wait_queue(sk_sleep(session->ctrl_sock->sk), &ctrl_wait);
1278 add_wait_queue(sk_sleep(session->intr_sock->sk), &intr_wait);
1279 /* This memory barrier is paired with wq_has_sleeper(). See
1280 * sock_poll_wait() for more information why this is needed. */
1281 smp_mb__before_atomic();
1283 /* notify synchronous startup that we're ready */
1284 atomic_inc(&session->state);
1285 wake_up(&session->state_queue);
1288 hidp_session_run(session);
1290 /* cleanup runtime environment */
1291 remove_wait_queue(sk_sleep(session->intr_sock->sk), &intr_wait);
1292 remove_wait_queue(sk_sleep(session->ctrl_sock->sk), &ctrl_wait);
1293 wake_up_interruptible(&session->report_queue);
1294 hidp_del_timer(session);
1297 * If we stopped ourself due to any internal signal, we should try to
1298 * unregister our own session here to avoid having it linger until the
1299 * parent l2cap_conn dies or user-space cleans it up.
1300 * This does not deadlock as we don't do any synchronous shutdown.
1301 * Instead, this call has the same semantics as if user-space tried to
1302 * delete the session.
1304 l2cap_unregister_user(session->conn, &session->user);
1305 hidp_session_put(session);
1307 module_put_and_kthread_exit(0);
1311 static int hidp_verify_sockets(struct socket *ctrl_sock,
1312 struct socket *intr_sock)
1314 struct l2cap_chan *ctrl_chan, *intr_chan;
1315 struct bt_sock *ctrl, *intr;
1316 struct hidp_session *session;
1318 if (!l2cap_is_socket(ctrl_sock) || !l2cap_is_socket(intr_sock))
1321 ctrl_chan = l2cap_pi(ctrl_sock->sk)->chan;
1322 intr_chan = l2cap_pi(intr_sock->sk)->chan;
1324 if (bacmp(&ctrl_chan->src, &intr_chan->src) ||
1325 bacmp(&ctrl_chan->dst, &intr_chan->dst))
1328 ctrl = bt_sk(ctrl_sock->sk);
1329 intr = bt_sk(intr_sock->sk);
1331 if (ctrl->sk.sk_state != BT_CONNECTED ||
1332 intr->sk.sk_state != BT_CONNECTED)
1335 /* early session check, we check again during session registration */
1336 session = hidp_session_find(&ctrl_chan->dst);
1338 hidp_session_put(session);
1345 int hidp_connection_add(const struct hidp_connadd_req *req,
1346 struct socket *ctrl_sock,
1347 struct socket *intr_sock)
1349 u32 valid_flags = BIT(HIDP_VIRTUAL_CABLE_UNPLUG) |
1350 BIT(HIDP_BOOT_PROTOCOL_MODE);
1351 struct hidp_session *session;
1352 struct l2cap_conn *conn;
1353 struct l2cap_chan *chan;
1356 ret = hidp_verify_sockets(ctrl_sock, intr_sock);
1360 if (req->flags & ~valid_flags)
1363 chan = l2cap_pi(ctrl_sock->sk)->chan;
1365 l2cap_chan_lock(chan);
1367 conn = l2cap_conn_get(chan->conn);
1368 l2cap_chan_unlock(chan);
1373 ret = hidp_session_new(&session, &chan->dst, ctrl_sock,
1374 intr_sock, req, conn);
1378 ret = l2cap_register_user(conn, &session->user);
1385 hidp_session_put(session);
1387 l2cap_conn_put(conn);
1391 int hidp_connection_del(struct hidp_conndel_req *req)
1393 u32 valid_flags = BIT(HIDP_VIRTUAL_CABLE_UNPLUG);
1394 struct hidp_session *session;
1396 if (req->flags & ~valid_flags)
1399 session = hidp_session_find(&req->bdaddr);
1403 if (req->flags & BIT(HIDP_VIRTUAL_CABLE_UNPLUG))
1404 hidp_send_ctrl_message(session,
1405 HIDP_TRANS_HID_CONTROL |
1406 HIDP_CTRL_VIRTUAL_CABLE_UNPLUG,
1409 l2cap_unregister_user(session->conn, &session->user);
1411 hidp_session_put(session);
1416 int hidp_get_connlist(struct hidp_connlist_req *req)
1418 struct hidp_session *session;
1423 down_read(&hidp_session_sem);
1425 list_for_each_entry(session, &hidp_session_list, list) {
1426 struct hidp_conninfo ci;
1428 hidp_copy_session(session, &ci);
1430 if (copy_to_user(req->ci, &ci, sizeof(ci))) {
1435 if (++n >= req->cnum)
1442 up_read(&hidp_session_sem);
1446 int hidp_get_conninfo(struct hidp_conninfo *ci)
1448 struct hidp_session *session;
1450 session = hidp_session_find(&ci->bdaddr);
1452 hidp_copy_session(session, ci);
1453 hidp_session_put(session);
1456 return session ? 0 : -ENOENT;
1459 static int __init hidp_init(void)
1461 BT_INFO("HIDP (Human Interface Emulation) ver %s", VERSION);
1463 return hidp_init_sockets();
1466 static void __exit hidp_exit(void)
1468 hidp_cleanup_sockets();
1471 module_init(hidp_init);
1472 module_exit(hidp_exit);
1474 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
1475 MODULE_AUTHOR("David Herrmann <dh.herrmann@gmail.com>");
1476 MODULE_DESCRIPTION("Bluetooth HIDP ver " VERSION);
1477 MODULE_VERSION(VERSION);
1478 MODULE_LICENSE("GPL");
1479 MODULE_ALIAS("bt-proto-6");