Commit | Line | Data |
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7dec65c8 JH |
1 | /* |
2 | * | |
3 | * Bluetooth HCI Three-wire UART driver | |
4 | * | |
5 | * Copyright (C) 2012 Intel Corporation | |
6 | * | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
21 | * | |
22 | */ | |
23 | ||
24 | #include <linux/kernel.h> | |
25 | #include <linux/errno.h> | |
26 | #include <linux/skbuff.h> | |
27 | ||
28 | #include <net/bluetooth/bluetooth.h> | |
29 | #include <net/bluetooth/hci_core.h> | |
30 | ||
31 | #include "hci_uart.h" | |
32 | ||
c0a1b73c JH |
33 | #define HCI_3WIRE_ACK_PKT 0 |
34 | #define HCI_3WIRE_LINK_PKT 15 | |
35 | ||
afdc944c JH |
36 | /* Sliding window size */ |
37 | #define H5_TX_WIN_MAX 4 | |
3f27e95b JH |
38 | |
39 | #define H5_ACK_TIMEOUT msecs_to_jiffies(250) | |
40f10224 | 40 | #define H5_SYNC_TIMEOUT msecs_to_jiffies(100) |
3f27e95b | 41 | |
bc1f35b9 JH |
42 | /* |
43 | * Maximum Three-wire packet: | |
44 | * 4 byte header + max value for 12-bit length + 2 bytes for CRC | |
45 | */ | |
46 | #define H5_MAX_LEN (4 + 0xfff + 2) | |
47 | ||
01977c0b JH |
48 | /* Convenience macros for reading Three-wire header values */ |
49 | #define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07) | |
50 | #define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07) | |
51 | #define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01) | |
52 | #define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01) | |
53 | #define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f) | |
54 | #define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0xff) + ((hdr)[2] << 4)) | |
55 | ||
bc1f35b9 JH |
56 | #define SLIP_DELIMITER 0xc0 |
57 | #define SLIP_ESC 0xdb | |
58 | #define SLIP_ESC_DELIM 0xdc | |
59 | #define SLIP_ESC_ESC 0xdd | |
60 | ||
e0482103 JH |
61 | /* H5 state flags */ |
62 | enum { | |
63 | H5_RX_ESC, /* SLIP escape mode */ | |
64 | H5_TX_ACK_REQ, /* Pending ack to send */ | |
65 | }; | |
66 | ||
7d664fba | 67 | struct h5 { |
bc1f35b9 JH |
68 | struct sk_buff_head unack; /* Unack'ed packets queue */ |
69 | struct sk_buff_head rel; /* Reliable packets queue */ | |
70 | struct sk_buff_head unrel; /* Unreliable packets queue */ | |
71 | ||
e0482103 JH |
72 | unsigned long flags; |
73 | ||
bc1f35b9 JH |
74 | struct sk_buff *rx_skb; /* Receive buffer */ |
75 | size_t rx_pending; /* Expecting more bytes */ | |
43eb12d7 | 76 | u8 rx_ack; /* Last ack number received */ |
7d664fba | 77 | |
bc1f35b9 | 78 | int (*rx_func) (struct hci_uart *hu, u8 c); |
7d664fba | 79 | |
bc1f35b9 | 80 | struct timer_list timer; /* Retransmission timer */ |
3f27e95b | 81 | |
43eb12d7 | 82 | u8 tx_seq; /* Next seq number to send */ |
40f10224 | 83 | u8 tx_ack; /* Next ack number to send */ |
afdc944c | 84 | u8 tx_win; /* Sliding window size */ |
10122d07 | 85 | |
f674a057 JH |
86 | enum { |
87 | H5_UNINITIALIZED, | |
88 | H5_INITIALIZED, | |
89 | H5_ACTIVE, | |
90 | } state; | |
91 | ||
95c5c220 JH |
92 | enum { |
93 | H5_AWAKE, | |
94 | H5_SLEEPING, | |
95 | H5_WAKING_UP, | |
96 | } sleep; | |
7d664fba JH |
97 | }; |
98 | ||
bc1f35b9 JH |
99 | static void h5_reset_rx(struct h5 *h5); |
100 | ||
f674a057 JH |
101 | static void h5_link_control(struct hci_uart *hu, const void *data, size_t len) |
102 | { | |
103 | struct h5 *h5 = hu->priv; | |
104 | struct sk_buff *nskb; | |
105 | ||
106 | nskb = alloc_skb(3, GFP_ATOMIC); | |
107 | if (!nskb) | |
108 | return; | |
109 | ||
110 | bt_cb(nskb)->pkt_type = HCI_3WIRE_LINK_PKT; | |
111 | ||
112 | memcpy(skb_put(nskb, len), data, len); | |
113 | ||
114 | skb_queue_tail(&h5->unrel, nskb); | |
115 | } | |
116 | ||
afdc944c JH |
117 | static u8 h5_cfg_field(struct h5 *h5) |
118 | { | |
119 | u8 field = 0; | |
120 | ||
121 | /* Sliding window size (first 3 bits) */ | |
122 | field |= (h5->tx_win & 7); | |
123 | ||
124 | return field; | |
125 | } | |
126 | ||
3f27e95b JH |
127 | static void h5_timed_event(unsigned long arg) |
128 | { | |
f674a057 | 129 | const unsigned char sync_req[] = { 0x01, 0x7e }; |
afdc944c | 130 | unsigned char conf_req[] = { 0x03, 0xfc, 0x01 }; |
3f27e95b JH |
131 | struct hci_uart *hu = (struct hci_uart *) arg; |
132 | struct h5 *h5 = hu->priv; | |
133 | struct sk_buff *skb; | |
134 | unsigned long flags; | |
135 | ||
95c5c220 JH |
136 | BT_DBG("%s", hu->hdev->name); |
137 | ||
f674a057 JH |
138 | if (h5->state == H5_UNINITIALIZED) |
139 | h5_link_control(hu, sync_req, sizeof(sync_req)); | |
140 | ||
afdc944c JH |
141 | if (h5->state == H5_INITIALIZED) { |
142 | conf_req[2] = h5_cfg_field(h5); | |
f674a057 | 143 | h5_link_control(hu, conf_req, sizeof(conf_req)); |
afdc944c | 144 | } |
f674a057 JH |
145 | |
146 | if (h5->state != H5_ACTIVE) { | |
147 | mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); | |
148 | goto wakeup; | |
149 | } | |
150 | ||
95c5c220 JH |
151 | if (h5->sleep != H5_AWAKE) { |
152 | h5->sleep = H5_SLEEPING; | |
153 | goto wakeup; | |
154 | } | |
155 | ||
3f27e95b JH |
156 | BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen); |
157 | ||
158 | spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); | |
159 | ||
160 | while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) { | |
43eb12d7 | 161 | h5->tx_seq = (h5->tx_seq - 1) & 0x07; |
3f27e95b JH |
162 | skb_queue_head(&h5->rel, skb); |
163 | } | |
164 | ||
165 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
166 | ||
f674a057 | 167 | wakeup: |
3f27e95b JH |
168 | hci_uart_tx_wakeup(hu); |
169 | } | |
170 | ||
7dec65c8 JH |
171 | static int h5_open(struct hci_uart *hu) |
172 | { | |
7d664fba | 173 | struct h5 *h5; |
40f10224 | 174 | const unsigned char sync[] = { 0x01, 0x7e }; |
7d664fba JH |
175 | |
176 | BT_DBG("hu %p", hu); | |
177 | ||
178 | h5 = kzalloc(sizeof(*h5), GFP_KERNEL); | |
179 | if (!h5) | |
180 | return -ENOMEM; | |
181 | ||
182 | hu->priv = h5; | |
183 | ||
184 | skb_queue_head_init(&h5->unack); | |
185 | skb_queue_head_init(&h5->rel); | |
186 | skb_queue_head_init(&h5->unrel); | |
187 | ||
bc1f35b9 JH |
188 | h5_reset_rx(h5); |
189 | ||
3f27e95b JH |
190 | init_timer(&h5->timer); |
191 | h5->timer.function = h5_timed_event; | |
192 | h5->timer.data = (unsigned long) hu; | |
193 | ||
afdc944c JH |
194 | h5->tx_win = H5_TX_WIN_MAX; |
195 | ||
cd1b4425 JH |
196 | set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags); |
197 | ||
40f10224 JH |
198 | /* Send initial sync request */ |
199 | h5_link_control(hu, sync, sizeof(sync)); | |
200 | mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); | |
201 | ||
7d664fba | 202 | return 0; |
7dec65c8 JH |
203 | } |
204 | ||
205 | static int h5_close(struct hci_uart *hu) | |
206 | { | |
7d664fba JH |
207 | struct h5 *h5 = hu->priv; |
208 | ||
c327cddd MK |
209 | del_timer_sync(&h5->timer); |
210 | ||
7d664fba JH |
211 | skb_queue_purge(&h5->unack); |
212 | skb_queue_purge(&h5->rel); | |
213 | skb_queue_purge(&h5->unrel); | |
214 | ||
215 | kfree(h5); | |
216 | ||
217 | return 0; | |
7dec65c8 JH |
218 | } |
219 | ||
43eb12d7 JH |
220 | static void h5_pkt_cull(struct h5 *h5) |
221 | { | |
222 | struct sk_buff *skb, *tmp; | |
223 | unsigned long flags; | |
224 | int i, to_remove; | |
225 | u8 seq; | |
226 | ||
227 | spin_lock_irqsave(&h5->unack.lock, flags); | |
228 | ||
229 | to_remove = skb_queue_len(&h5->unack); | |
40f10224 JH |
230 | if (to_remove == 0) |
231 | goto unlock; | |
43eb12d7 JH |
232 | |
233 | seq = h5->tx_seq; | |
234 | ||
235 | while (to_remove > 0) { | |
236 | if (h5->rx_ack == seq) | |
237 | break; | |
238 | ||
239 | to_remove--; | |
4807b518 | 240 | seq = (seq - 1) & 0x07; |
43eb12d7 JH |
241 | } |
242 | ||
243 | if (seq != h5->rx_ack) | |
244 | BT_ERR("Controller acked invalid packet"); | |
245 | ||
246 | i = 0; | |
247 | skb_queue_walk_safe(&h5->unack, skb, tmp) { | |
248 | if (i++ >= to_remove) | |
249 | break; | |
250 | ||
251 | __skb_unlink(skb, &h5->unack); | |
252 | kfree_skb(skb); | |
253 | } | |
254 | ||
255 | if (skb_queue_empty(&h5->unack)) | |
256 | del_timer(&h5->timer); | |
257 | ||
40f10224 | 258 | unlock: |
43eb12d7 JH |
259 | spin_unlock_irqrestore(&h5->unack.lock, flags); |
260 | } | |
261 | ||
bc1f35b9 JH |
262 | static void h5_handle_internal_rx(struct hci_uart *hu) |
263 | { | |
40f10224 JH |
264 | struct h5 *h5 = hu->priv; |
265 | const unsigned char sync_req[] = { 0x01, 0x7e }; | |
266 | const unsigned char sync_rsp[] = { 0x02, 0x7d }; | |
afdc944c JH |
267 | unsigned char conf_req[] = { 0x03, 0xfc, 0x01 }; |
268 | const unsigned char conf_rsp[] = { 0x04, 0x7b }; | |
10122d07 JH |
269 | const unsigned char wakeup_req[] = { 0x05, 0xfa }; |
270 | const unsigned char woken_req[] = { 0x06, 0xf9 }; | |
271 | const unsigned char sleep_req[] = { 0x07, 0x78 }; | |
40f10224 JH |
272 | const unsigned char *hdr = h5->rx_skb->data; |
273 | const unsigned char *data = &h5->rx_skb->data[4]; | |
274 | ||
bc1f35b9 | 275 | BT_DBG("%s", hu->hdev->name); |
40f10224 JH |
276 | |
277 | if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) | |
278 | return; | |
279 | ||
280 | if (H5_HDR_LEN(hdr) < 2) | |
281 | return; | |
282 | ||
afdc944c JH |
283 | conf_req[2] = h5_cfg_field(h5); |
284 | ||
40f10224 JH |
285 | if (memcmp(data, sync_req, 2) == 0) { |
286 | h5_link_control(hu, sync_rsp, 2); | |
287 | } else if (memcmp(data, sync_rsp, 2) == 0) { | |
f674a057 | 288 | h5->state = H5_INITIALIZED; |
40f10224 JH |
289 | h5_link_control(hu, conf_req, 3); |
290 | } else if (memcmp(data, conf_req, 2) == 0) { | |
291 | h5_link_control(hu, conf_rsp, 2); | |
292 | h5_link_control(hu, conf_req, 3); | |
293 | } else if (memcmp(data, conf_rsp, 2) == 0) { | |
afdc944c JH |
294 | if (H5_HDR_LEN(hdr) > 2) |
295 | h5->tx_win = (data[2] & 7); | |
296 | BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win); | |
f674a057 | 297 | h5->state = H5_ACTIVE; |
cd1b4425 | 298 | hci_uart_init_ready(hu); |
40f10224 | 299 | return; |
10122d07 JH |
300 | } else if (memcmp(data, sleep_req, 2) == 0) { |
301 | BT_DBG("Peer went to sleep"); | |
95c5c220 JH |
302 | h5->sleep = H5_SLEEPING; |
303 | return; | |
10122d07 JH |
304 | } else if (memcmp(data, woken_req, 2) == 0) { |
305 | BT_DBG("Peer woke up"); | |
95c5c220 JH |
306 | h5->sleep = H5_AWAKE; |
307 | } else if (memcmp(data, wakeup_req, 2) == 0) { | |
308 | BT_DBG("Peer requested wakeup"); | |
309 | h5_link_control(hu, woken_req, 2); | |
310 | h5->sleep = H5_AWAKE; | |
40f10224 JH |
311 | } else { |
312 | BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]); | |
313 | return; | |
314 | } | |
315 | ||
316 | hci_uart_tx_wakeup(hu); | |
bc1f35b9 JH |
317 | } |
318 | ||
319 | static void h5_complete_rx_pkt(struct hci_uart *hu) | |
320 | { | |
321 | struct h5 *h5 = hu->priv; | |
43eb12d7 | 322 | const unsigned char *hdr = h5->rx_skb->data; |
bc1f35b9 | 323 | |
43eb12d7 | 324 | if (H5_HDR_RELIABLE(hdr)) { |
40f10224 | 325 | h5->tx_ack = (h5->tx_ack + 1) % 8; |
e0482103 | 326 | set_bit(H5_TX_ACK_REQ, &h5->flags); |
40f10224 | 327 | hci_uart_tx_wakeup(hu); |
43eb12d7 | 328 | } |
bc1f35b9 | 329 | |
43eb12d7 JH |
330 | h5->rx_ack = H5_HDR_ACK(hdr); |
331 | ||
332 | h5_pkt_cull(h5); | |
333 | ||
334 | switch (H5_HDR_PKT_TYPE(hdr)) { | |
bc1f35b9 JH |
335 | case HCI_EVENT_PKT: |
336 | case HCI_ACLDATA_PKT: | |
337 | case HCI_SCODATA_PKT: | |
43eb12d7 | 338 | bt_cb(h5->rx_skb)->pkt_type = H5_HDR_PKT_TYPE(hdr); |
bc1f35b9 JH |
339 | |
340 | /* Remove Three-wire header */ | |
341 | skb_pull(h5->rx_skb, 4); | |
342 | ||
e1a26170 | 343 | hci_recv_frame(hu->hdev, h5->rx_skb); |
bc1f35b9 JH |
344 | h5->rx_skb = NULL; |
345 | ||
346 | break; | |
347 | ||
348 | default: | |
349 | h5_handle_internal_rx(hu); | |
350 | break; | |
351 | } | |
352 | ||
353 | h5_reset_rx(h5); | |
354 | } | |
355 | ||
356 | static int h5_rx_crc(struct hci_uart *hu, unsigned char c) | |
357 | { | |
bc1f35b9 | 358 | h5_complete_rx_pkt(hu); |
bc1f35b9 JH |
359 | |
360 | return 0; | |
361 | } | |
362 | ||
363 | static int h5_rx_payload(struct hci_uart *hu, unsigned char c) | |
364 | { | |
365 | struct h5 *h5 = hu->priv; | |
366 | const unsigned char *hdr = h5->rx_skb->data; | |
367 | ||
43eb12d7 | 368 | if (H5_HDR_CRC(hdr)) { |
bc1f35b9 JH |
369 | h5->rx_func = h5_rx_crc; |
370 | h5->rx_pending = 2; | |
371 | } else { | |
372 | h5_complete_rx_pkt(hu); | |
bc1f35b9 JH |
373 | } |
374 | ||
375 | return 0; | |
376 | } | |
377 | ||
378 | static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c) | |
379 | { | |
380 | struct h5 *h5 = hu->priv; | |
381 | const unsigned char *hdr = h5->rx_skb->data; | |
382 | ||
40f10224 JH |
383 | BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u", |
384 | hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), | |
385 | H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), | |
386 | H5_HDR_LEN(hdr)); | |
387 | ||
bc1f35b9 JH |
388 | if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) { |
389 | BT_ERR("Invalid header checksum"); | |
390 | h5_reset_rx(h5); | |
391 | return 0; | |
392 | } | |
393 | ||
40f10224 | 394 | if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) { |
43eb12d7 | 395 | BT_ERR("Out-of-order packet arrived (%u != %u)", |
40f10224 | 396 | H5_HDR_SEQ(hdr), h5->tx_ack); |
43eb12d7 JH |
397 | h5_reset_rx(h5); |
398 | return 0; | |
399 | } | |
400 | ||
f674a057 JH |
401 | if (h5->state != H5_ACTIVE && |
402 | H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) { | |
403 | BT_ERR("Non-link packet received in non-active state"); | |
404 | h5_reset_rx(h5); | |
48439d50 | 405 | return 0; |
f674a057 JH |
406 | } |
407 | ||
bc1f35b9 | 408 | h5->rx_func = h5_rx_payload; |
43eb12d7 | 409 | h5->rx_pending = H5_HDR_LEN(hdr); |
bc1f35b9 JH |
410 | |
411 | return 0; | |
412 | } | |
413 | ||
414 | static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c) | |
415 | { | |
416 | struct h5 *h5 = hu->priv; | |
417 | ||
bc1f35b9 JH |
418 | if (c == SLIP_DELIMITER) |
419 | return 1; | |
420 | ||
421 | h5->rx_func = h5_rx_3wire_hdr; | |
422 | h5->rx_pending = 4; | |
423 | ||
424 | h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC); | |
425 | if (!h5->rx_skb) { | |
426 | BT_ERR("Can't allocate mem for new packet"); | |
427 | h5_reset_rx(h5); | |
428 | return -ENOMEM; | |
429 | } | |
430 | ||
431 | h5->rx_skb->dev = (void *) hu->hdev; | |
432 | ||
433 | return 0; | |
434 | } | |
435 | ||
436 | static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c) | |
437 | { | |
438 | struct h5 *h5 = hu->priv; | |
439 | ||
bc1f35b9 JH |
440 | if (c == SLIP_DELIMITER) |
441 | h5->rx_func = h5_rx_pkt_start; | |
442 | ||
443 | return 1; | |
444 | } | |
445 | ||
446 | static void h5_unslip_one_byte(struct h5 *h5, unsigned char c) | |
447 | { | |
448 | const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC; | |
449 | const u8 *byte = &c; | |
450 | ||
e0482103 JH |
451 | if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) { |
452 | set_bit(H5_RX_ESC, &h5->flags); | |
bc1f35b9 JH |
453 | return; |
454 | } | |
455 | ||
e0482103 | 456 | if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) { |
bc1f35b9 JH |
457 | switch (c) { |
458 | case SLIP_ESC_DELIM: | |
459 | byte = &delim; | |
460 | break; | |
461 | case SLIP_ESC_ESC: | |
462 | byte = &esc; | |
463 | break; | |
464 | default: | |
465 | BT_ERR("Invalid esc byte 0x%02hhx", c); | |
466 | h5_reset_rx(h5); | |
467 | return; | |
468 | } | |
bc1f35b9 JH |
469 | } |
470 | ||
471 | memcpy(skb_put(h5->rx_skb, 1), byte, 1); | |
472 | h5->rx_pending--; | |
473 | ||
255a68e0 | 474 | BT_DBG("unsliped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending); |
bc1f35b9 JH |
475 | } |
476 | ||
477 | static void h5_reset_rx(struct h5 *h5) | |
478 | { | |
479 | if (h5->rx_skb) { | |
480 | kfree_skb(h5->rx_skb); | |
481 | h5->rx_skb = NULL; | |
482 | } | |
483 | ||
484 | h5->rx_func = h5_rx_delimiter; | |
485 | h5->rx_pending = 0; | |
e0482103 | 486 | clear_bit(H5_RX_ESC, &h5->flags); |
bc1f35b9 JH |
487 | } |
488 | ||
7dec65c8 JH |
489 | static int h5_recv(struct hci_uart *hu, void *data, int count) |
490 | { | |
bc1f35b9 JH |
491 | struct h5 *h5 = hu->priv; |
492 | unsigned char *ptr = data; | |
493 | ||
255a68e0 JH |
494 | BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending, |
495 | count); | |
bc1f35b9 JH |
496 | |
497 | while (count > 0) { | |
498 | int processed; | |
499 | ||
500 | if (h5->rx_pending > 0) { | |
501 | if (*ptr == SLIP_DELIMITER) { | |
502 | BT_ERR("Too short H5 packet"); | |
503 | h5_reset_rx(h5); | |
504 | continue; | |
505 | } | |
506 | ||
507 | h5_unslip_one_byte(h5, *ptr); | |
508 | ||
509 | ptr++; count--; | |
510 | continue; | |
511 | } | |
512 | ||
513 | processed = h5->rx_func(hu, *ptr); | |
514 | if (processed < 0) | |
515 | return processed; | |
516 | ||
517 | ptr += processed; | |
518 | count -= processed; | |
519 | } | |
520 | ||
521 | return 0; | |
7dec65c8 JH |
522 | } |
523 | ||
524 | static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) | |
525 | { | |
7d664fba JH |
526 | struct h5 *h5 = hu->priv; |
527 | ||
528 | if (skb->len > 0xfff) { | |
529 | BT_ERR("Packet too long (%u bytes)", skb->len); | |
530 | kfree_skb(skb); | |
531 | return 0; | |
532 | } | |
533 | ||
f674a057 JH |
534 | if (h5->state != H5_ACTIVE) { |
535 | BT_ERR("Ignoring HCI data in non-active state"); | |
536 | kfree_skb(skb); | |
537 | return 0; | |
538 | } | |
539 | ||
7d664fba JH |
540 | switch (bt_cb(skb)->pkt_type) { |
541 | case HCI_ACLDATA_PKT: | |
542 | case HCI_COMMAND_PKT: | |
543 | skb_queue_tail(&h5->rel, skb); | |
544 | break; | |
545 | ||
546 | case HCI_SCODATA_PKT: | |
547 | skb_queue_tail(&h5->unrel, skb); | |
548 | break; | |
549 | ||
550 | default: | |
551 | BT_ERR("Unknown packet type %u", bt_cb(skb)->pkt_type); | |
552 | kfree_skb(skb); | |
553 | break; | |
554 | } | |
555 | ||
556 | return 0; | |
557 | } | |
558 | ||
c0a1b73c JH |
559 | static void h5_slip_delim(struct sk_buff *skb) |
560 | { | |
561 | const char delim = SLIP_DELIMITER; | |
562 | ||
563 | memcpy(skb_put(skb, 1), &delim, 1); | |
564 | } | |
565 | ||
566 | static void h5_slip_one_byte(struct sk_buff *skb, u8 c) | |
567 | { | |
568 | const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM }; | |
569 | const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC }; | |
570 | ||
571 | switch (c) { | |
572 | case SLIP_DELIMITER: | |
573 | memcpy(skb_put(skb, 2), &esc_delim, 2); | |
574 | break; | |
575 | case SLIP_ESC: | |
576 | memcpy(skb_put(skb, 2), &esc_esc, 2); | |
577 | break; | |
578 | default: | |
579 | memcpy(skb_put(skb, 1), &c, 1); | |
580 | } | |
581 | } | |
582 | ||
c826ed09 JH |
583 | static bool valid_packet_type(u8 type) |
584 | { | |
585 | switch (type) { | |
586 | case HCI_ACLDATA_PKT: | |
587 | case HCI_COMMAND_PKT: | |
588 | case HCI_SCODATA_PKT: | |
589 | case HCI_3WIRE_LINK_PKT: | |
590 | case HCI_3WIRE_ACK_PKT: | |
591 | return true; | |
592 | default: | |
593 | return false; | |
594 | } | |
595 | } | |
596 | ||
597 | static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type, | |
598 | const u8 *data, size_t len) | |
7d664fba | 599 | { |
40f10224 | 600 | struct h5 *h5 = hu->priv; |
c0a1b73c JH |
601 | struct sk_buff *nskb; |
602 | u8 hdr[4]; | |
603 | int i; | |
604 | ||
c826ed09 JH |
605 | if (!valid_packet_type(pkt_type)) { |
606 | BT_ERR("Unknown packet type %u", pkt_type); | |
607 | return NULL; | |
608 | } | |
609 | ||
c0a1b73c JH |
610 | /* |
611 | * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2 | |
612 | * (because bytes 0xc0 and 0xdb are escaped, worst case is when | |
613 | * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0 | |
614 | * delimiters at start and end). | |
615 | */ | |
616 | nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC); | |
617 | if (!nskb) | |
618 | return NULL; | |
619 | ||
620 | bt_cb(nskb)->pkt_type = pkt_type; | |
621 | ||
622 | h5_slip_delim(nskb); | |
623 | ||
40f10224 | 624 | hdr[0] = h5->tx_ack << 3; |
e0482103 | 625 | clear_bit(H5_TX_ACK_REQ, &h5->flags); |
c0a1b73c | 626 | |
c826ed09 JH |
627 | /* Reliable packet? */ |
628 | if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) { | |
c0a1b73c | 629 | hdr[0] |= 1 << 7; |
43eb12d7 JH |
630 | hdr[0] |= h5->tx_seq; |
631 | h5->tx_seq = (h5->tx_seq + 1) % 8; | |
c0a1b73c JH |
632 | } |
633 | ||
634 | hdr[1] = pkt_type | ((len & 0x0f) << 4); | |
635 | hdr[2] = len >> 4; | |
636 | hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff); | |
637 | ||
40f10224 JH |
638 | BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u", |
639 | hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), | |
640 | H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), | |
641 | H5_HDR_LEN(hdr)); | |
642 | ||
c0a1b73c JH |
643 | for (i = 0; i < 4; i++) |
644 | h5_slip_one_byte(nskb, hdr[i]); | |
645 | ||
646 | for (i = 0; i < len; i++) | |
647 | h5_slip_one_byte(nskb, data[i]); | |
648 | ||
649 | h5_slip_delim(nskb); | |
650 | ||
651 | return nskb; | |
652 | } | |
653 | ||
7dec65c8 JH |
654 | static struct sk_buff *h5_dequeue(struct hci_uart *hu) |
655 | { | |
7d664fba | 656 | struct h5 *h5 = hu->priv; |
3f27e95b | 657 | unsigned long flags; |
7d664fba JH |
658 | struct sk_buff *skb, *nskb; |
659 | ||
95c5c220 JH |
660 | if (h5->sleep != H5_AWAKE) { |
661 | const unsigned char wakeup_req[] = { 0x05, 0xfa }; | |
662 | ||
663 | if (h5->sleep == H5_WAKING_UP) | |
664 | return NULL; | |
665 | ||
666 | h5->sleep = H5_WAKING_UP; | |
667 | BT_DBG("Sending wakeup request"); | |
668 | ||
669 | mod_timer(&h5->timer, jiffies + HZ / 100); | |
670 | return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2); | |
671 | } | |
672 | ||
a08b15e6 VI |
673 | skb = skb_dequeue(&h5->unrel); |
674 | if (skb != NULL) { | |
40f10224 | 675 | nskb = h5_prepare_pkt(hu, bt_cb(skb)->pkt_type, |
c0a1b73c | 676 | skb->data, skb->len); |
7d664fba JH |
677 | if (nskb) { |
678 | kfree_skb(skb); | |
679 | return nskb; | |
680 | } | |
681 | ||
682 | skb_queue_head(&h5->unrel, skb); | |
683 | BT_ERR("Could not dequeue pkt because alloc_skb failed"); | |
684 | } | |
685 | ||
3f27e95b JH |
686 | spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); |
687 | ||
afdc944c | 688 | if (h5->unack.qlen >= h5->tx_win) |
3f27e95b JH |
689 | goto unlock; |
690 | ||
a08b15e6 VI |
691 | skb = skb_dequeue(&h5->rel); |
692 | if (skb != NULL) { | |
40f10224 | 693 | nskb = h5_prepare_pkt(hu, bt_cb(skb)->pkt_type, |
c0a1b73c | 694 | skb->data, skb->len); |
3f27e95b JH |
695 | if (nskb) { |
696 | __skb_queue_tail(&h5->unack, skb); | |
697 | mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT); | |
698 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
699 | return nskb; | |
700 | } | |
701 | ||
702 | skb_queue_head(&h5->rel, skb); | |
703 | BT_ERR("Could not dequeue pkt because alloc_skb failed"); | |
704 | } | |
705 | ||
706 | unlock: | |
707 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
708 | ||
e0482103 | 709 | if (test_bit(H5_TX_ACK_REQ, &h5->flags)) |
40f10224 | 710 | return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0); |
7d664fba | 711 | |
7dec65c8 JH |
712 | return NULL; |
713 | } | |
714 | ||
715 | static int h5_flush(struct hci_uart *hu) | |
716 | { | |
7d664fba JH |
717 | BT_DBG("hu %p", hu); |
718 | return 0; | |
7dec65c8 JH |
719 | } |
720 | ||
721 | static struct hci_uart_proto h5p = { | |
722 | .id = HCI_UART_3WIRE, | |
723 | .open = h5_open, | |
724 | .close = h5_close, | |
725 | .recv = h5_recv, | |
726 | .enqueue = h5_enqueue, | |
727 | .dequeue = h5_dequeue, | |
728 | .flush = h5_flush, | |
729 | }; | |
730 | ||
731 | int __init h5_init(void) | |
732 | { | |
733 | int err = hci_uart_register_proto(&h5p); | |
734 | ||
735 | if (!err) | |
736 | BT_INFO("HCI Three-wire UART (H5) protocol initialized"); | |
737 | else | |
738 | BT_ERR("HCI Three-wire UART (H5) protocol init failed"); | |
739 | ||
740 | return err; | |
741 | } | |
742 | ||
743 | int __exit h5_deinit(void) | |
744 | { | |
745 | return hci_uart_unregister_proto(&h5p); | |
746 | } |