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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 | ||
209 | skb_queue_purge(&h5->unack); | |
210 | skb_queue_purge(&h5->rel); | |
211 | skb_queue_purge(&h5->unrel); | |
212 | ||
3f27e95b JH |
213 | del_timer(&h5->timer); |
214 | ||
7d664fba JH |
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--; | |
240 | seq = (seq - 1) % 8; | |
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 | ||
343 | hci_recv_frame(h5->rx_skb); | |
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 | { | |
358 | struct h5 *h5 = hu->priv; | |
359 | ||
bc1f35b9 JH |
360 | h5_complete_rx_pkt(hu); |
361 | h5_reset_rx(h5); | |
362 | ||
363 | return 0; | |
364 | } | |
365 | ||
366 | static int h5_rx_payload(struct hci_uart *hu, unsigned char c) | |
367 | { | |
368 | struct h5 *h5 = hu->priv; | |
369 | const unsigned char *hdr = h5->rx_skb->data; | |
370 | ||
43eb12d7 | 371 | if (H5_HDR_CRC(hdr)) { |
bc1f35b9 JH |
372 | h5->rx_func = h5_rx_crc; |
373 | h5->rx_pending = 2; | |
374 | } else { | |
375 | h5_complete_rx_pkt(hu); | |
376 | h5_reset_rx(h5); | |
377 | } | |
378 | ||
379 | return 0; | |
380 | } | |
381 | ||
382 | static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c) | |
383 | { | |
384 | struct h5 *h5 = hu->priv; | |
385 | const unsigned char *hdr = h5->rx_skb->data; | |
386 | ||
40f10224 JH |
387 | BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u", |
388 | hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), | |
389 | H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), | |
390 | H5_HDR_LEN(hdr)); | |
391 | ||
bc1f35b9 JH |
392 | if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) { |
393 | BT_ERR("Invalid header checksum"); | |
394 | h5_reset_rx(h5); | |
395 | return 0; | |
396 | } | |
397 | ||
40f10224 | 398 | if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) { |
43eb12d7 | 399 | BT_ERR("Out-of-order packet arrived (%u != %u)", |
40f10224 | 400 | H5_HDR_SEQ(hdr), h5->tx_ack); |
43eb12d7 JH |
401 | h5_reset_rx(h5); |
402 | return 0; | |
403 | } | |
404 | ||
f674a057 JH |
405 | if (h5->state != H5_ACTIVE && |
406 | H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) { | |
407 | BT_ERR("Non-link packet received in non-active state"); | |
408 | h5_reset_rx(h5); | |
409 | } | |
410 | ||
bc1f35b9 | 411 | h5->rx_func = h5_rx_payload; |
43eb12d7 | 412 | h5->rx_pending = H5_HDR_LEN(hdr); |
bc1f35b9 JH |
413 | |
414 | return 0; | |
415 | } | |
416 | ||
417 | static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c) | |
418 | { | |
419 | struct h5 *h5 = hu->priv; | |
420 | ||
bc1f35b9 JH |
421 | if (c == SLIP_DELIMITER) |
422 | return 1; | |
423 | ||
424 | h5->rx_func = h5_rx_3wire_hdr; | |
425 | h5->rx_pending = 4; | |
426 | ||
427 | h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC); | |
428 | if (!h5->rx_skb) { | |
429 | BT_ERR("Can't allocate mem for new packet"); | |
430 | h5_reset_rx(h5); | |
431 | return -ENOMEM; | |
432 | } | |
433 | ||
434 | h5->rx_skb->dev = (void *) hu->hdev; | |
435 | ||
436 | return 0; | |
437 | } | |
438 | ||
439 | static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c) | |
440 | { | |
441 | struct h5 *h5 = hu->priv; | |
442 | ||
bc1f35b9 JH |
443 | if (c == SLIP_DELIMITER) |
444 | h5->rx_func = h5_rx_pkt_start; | |
445 | ||
446 | return 1; | |
447 | } | |
448 | ||
449 | static void h5_unslip_one_byte(struct h5 *h5, unsigned char c) | |
450 | { | |
451 | const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC; | |
452 | const u8 *byte = &c; | |
453 | ||
e0482103 JH |
454 | if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) { |
455 | set_bit(H5_RX_ESC, &h5->flags); | |
bc1f35b9 JH |
456 | return; |
457 | } | |
458 | ||
e0482103 | 459 | if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) { |
bc1f35b9 JH |
460 | switch (c) { |
461 | case SLIP_ESC_DELIM: | |
462 | byte = &delim; | |
463 | break; | |
464 | case SLIP_ESC_ESC: | |
465 | byte = &esc; | |
466 | break; | |
467 | default: | |
468 | BT_ERR("Invalid esc byte 0x%02hhx", c); | |
469 | h5_reset_rx(h5); | |
470 | return; | |
471 | } | |
bc1f35b9 JH |
472 | } |
473 | ||
474 | memcpy(skb_put(h5->rx_skb, 1), byte, 1); | |
475 | h5->rx_pending--; | |
476 | ||
255a68e0 | 477 | BT_DBG("unsliped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending); |
bc1f35b9 JH |
478 | } |
479 | ||
480 | static void h5_reset_rx(struct h5 *h5) | |
481 | { | |
482 | if (h5->rx_skb) { | |
483 | kfree_skb(h5->rx_skb); | |
484 | h5->rx_skb = NULL; | |
485 | } | |
486 | ||
487 | h5->rx_func = h5_rx_delimiter; | |
488 | h5->rx_pending = 0; | |
e0482103 | 489 | clear_bit(H5_RX_ESC, &h5->flags); |
bc1f35b9 JH |
490 | } |
491 | ||
7dec65c8 JH |
492 | static int h5_recv(struct hci_uart *hu, void *data, int count) |
493 | { | |
bc1f35b9 JH |
494 | struct h5 *h5 = hu->priv; |
495 | unsigned char *ptr = data; | |
496 | ||
255a68e0 JH |
497 | BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending, |
498 | count); | |
bc1f35b9 JH |
499 | |
500 | while (count > 0) { | |
501 | int processed; | |
502 | ||
503 | if (h5->rx_pending > 0) { | |
504 | if (*ptr == SLIP_DELIMITER) { | |
505 | BT_ERR("Too short H5 packet"); | |
506 | h5_reset_rx(h5); | |
507 | continue; | |
508 | } | |
509 | ||
510 | h5_unslip_one_byte(h5, *ptr); | |
511 | ||
512 | ptr++; count--; | |
513 | continue; | |
514 | } | |
515 | ||
516 | processed = h5->rx_func(hu, *ptr); | |
517 | if (processed < 0) | |
518 | return processed; | |
519 | ||
520 | ptr += processed; | |
521 | count -= processed; | |
522 | } | |
523 | ||
524 | return 0; | |
7dec65c8 JH |
525 | } |
526 | ||
527 | static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) | |
528 | { | |
7d664fba JH |
529 | struct h5 *h5 = hu->priv; |
530 | ||
531 | if (skb->len > 0xfff) { | |
532 | BT_ERR("Packet too long (%u bytes)", skb->len); | |
533 | kfree_skb(skb); | |
534 | return 0; | |
535 | } | |
536 | ||
f674a057 JH |
537 | if (h5->state != H5_ACTIVE) { |
538 | BT_ERR("Ignoring HCI data in non-active state"); | |
539 | kfree_skb(skb); | |
540 | return 0; | |
541 | } | |
542 | ||
7d664fba JH |
543 | switch (bt_cb(skb)->pkt_type) { |
544 | case HCI_ACLDATA_PKT: | |
545 | case HCI_COMMAND_PKT: | |
546 | skb_queue_tail(&h5->rel, skb); | |
547 | break; | |
548 | ||
549 | case HCI_SCODATA_PKT: | |
550 | skb_queue_tail(&h5->unrel, skb); | |
551 | break; | |
552 | ||
553 | default: | |
554 | BT_ERR("Unknown packet type %u", bt_cb(skb)->pkt_type); | |
555 | kfree_skb(skb); | |
556 | break; | |
557 | } | |
558 | ||
559 | return 0; | |
560 | } | |
561 | ||
c0a1b73c JH |
562 | static void h5_slip_delim(struct sk_buff *skb) |
563 | { | |
564 | const char delim = SLIP_DELIMITER; | |
565 | ||
566 | memcpy(skb_put(skb, 1), &delim, 1); | |
567 | } | |
568 | ||
569 | static void h5_slip_one_byte(struct sk_buff *skb, u8 c) | |
570 | { | |
571 | const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM }; | |
572 | const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC }; | |
573 | ||
574 | switch (c) { | |
575 | case SLIP_DELIMITER: | |
576 | memcpy(skb_put(skb, 2), &esc_delim, 2); | |
577 | break; | |
578 | case SLIP_ESC: | |
579 | memcpy(skb_put(skb, 2), &esc_esc, 2); | |
580 | break; | |
581 | default: | |
582 | memcpy(skb_put(skb, 1), &c, 1); | |
583 | } | |
584 | } | |
585 | ||
c826ed09 JH |
586 | static bool valid_packet_type(u8 type) |
587 | { | |
588 | switch (type) { | |
589 | case HCI_ACLDATA_PKT: | |
590 | case HCI_COMMAND_PKT: | |
591 | case HCI_SCODATA_PKT: | |
592 | case HCI_3WIRE_LINK_PKT: | |
593 | case HCI_3WIRE_ACK_PKT: | |
594 | return true; | |
595 | default: | |
596 | return false; | |
597 | } | |
598 | } | |
599 | ||
600 | static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type, | |
601 | const u8 *data, size_t len) | |
7d664fba | 602 | { |
40f10224 | 603 | struct h5 *h5 = hu->priv; |
c0a1b73c JH |
604 | struct sk_buff *nskb; |
605 | u8 hdr[4]; | |
606 | int i; | |
607 | ||
c826ed09 JH |
608 | if (!valid_packet_type(pkt_type)) { |
609 | BT_ERR("Unknown packet type %u", pkt_type); | |
610 | return NULL; | |
611 | } | |
612 | ||
c0a1b73c JH |
613 | /* |
614 | * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2 | |
615 | * (because bytes 0xc0 and 0xdb are escaped, worst case is when | |
616 | * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0 | |
617 | * delimiters at start and end). | |
618 | */ | |
619 | nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC); | |
620 | if (!nskb) | |
621 | return NULL; | |
622 | ||
623 | bt_cb(nskb)->pkt_type = pkt_type; | |
624 | ||
625 | h5_slip_delim(nskb); | |
626 | ||
40f10224 | 627 | hdr[0] = h5->tx_ack << 3; |
e0482103 | 628 | clear_bit(H5_TX_ACK_REQ, &h5->flags); |
c0a1b73c | 629 | |
c826ed09 JH |
630 | /* Reliable packet? */ |
631 | if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) { | |
c0a1b73c | 632 | hdr[0] |= 1 << 7; |
43eb12d7 JH |
633 | hdr[0] |= h5->tx_seq; |
634 | h5->tx_seq = (h5->tx_seq + 1) % 8; | |
c0a1b73c JH |
635 | } |
636 | ||
637 | hdr[1] = pkt_type | ((len & 0x0f) << 4); | |
638 | hdr[2] = len >> 4; | |
639 | hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff); | |
640 | ||
40f10224 JH |
641 | BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u", |
642 | hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), | |
643 | H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), | |
644 | H5_HDR_LEN(hdr)); | |
645 | ||
c0a1b73c JH |
646 | for (i = 0; i < 4; i++) |
647 | h5_slip_one_byte(nskb, hdr[i]); | |
648 | ||
649 | for (i = 0; i < len; i++) | |
650 | h5_slip_one_byte(nskb, data[i]); | |
651 | ||
652 | h5_slip_delim(nskb); | |
653 | ||
654 | return nskb; | |
655 | } | |
656 | ||
7dec65c8 JH |
657 | static struct sk_buff *h5_dequeue(struct hci_uart *hu) |
658 | { | |
7d664fba | 659 | struct h5 *h5 = hu->priv; |
3f27e95b | 660 | unsigned long flags; |
7d664fba JH |
661 | struct sk_buff *skb, *nskb; |
662 | ||
95c5c220 JH |
663 | if (h5->sleep != H5_AWAKE) { |
664 | const unsigned char wakeup_req[] = { 0x05, 0xfa }; | |
665 | ||
666 | if (h5->sleep == H5_WAKING_UP) | |
667 | return NULL; | |
668 | ||
669 | h5->sleep = H5_WAKING_UP; | |
670 | BT_DBG("Sending wakeup request"); | |
671 | ||
672 | mod_timer(&h5->timer, jiffies + HZ / 100); | |
673 | return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2); | |
674 | } | |
675 | ||
7d664fba | 676 | if ((skb = skb_dequeue(&h5->unrel)) != NULL) { |
40f10224 | 677 | nskb = h5_prepare_pkt(hu, bt_cb(skb)->pkt_type, |
c0a1b73c | 678 | skb->data, skb->len); |
7d664fba JH |
679 | if (nskb) { |
680 | kfree_skb(skb); | |
681 | return nskb; | |
682 | } | |
683 | ||
684 | skb_queue_head(&h5->unrel, skb); | |
685 | BT_ERR("Could not dequeue pkt because alloc_skb failed"); | |
686 | } | |
687 | ||
3f27e95b JH |
688 | spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); |
689 | ||
afdc944c | 690 | if (h5->unack.qlen >= h5->tx_win) |
3f27e95b JH |
691 | goto unlock; |
692 | ||
693 | if ((skb = skb_dequeue(&h5->rel)) != NULL) { | |
40f10224 | 694 | nskb = h5_prepare_pkt(hu, bt_cb(skb)->pkt_type, |
c0a1b73c | 695 | skb->data, skb->len); |
3f27e95b JH |
696 | if (nskb) { |
697 | __skb_queue_tail(&h5->unack, skb); | |
698 | mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT); | |
699 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
700 | return nskb; | |
701 | } | |
702 | ||
703 | skb_queue_head(&h5->rel, skb); | |
704 | BT_ERR("Could not dequeue pkt because alloc_skb failed"); | |
705 | } | |
706 | ||
707 | unlock: | |
708 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
709 | ||
e0482103 | 710 | if (test_bit(H5_TX_ACK_REQ, &h5->flags)) |
40f10224 | 711 | return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0); |
7d664fba | 712 | |
7dec65c8 JH |
713 | return NULL; |
714 | } | |
715 | ||
716 | static int h5_flush(struct hci_uart *hu) | |
717 | { | |
7d664fba JH |
718 | BT_DBG("hu %p", hu); |
719 | return 0; | |
7dec65c8 JH |
720 | } |
721 | ||
722 | static struct hci_uart_proto h5p = { | |
723 | .id = HCI_UART_3WIRE, | |
724 | .open = h5_open, | |
725 | .close = h5_close, | |
726 | .recv = h5_recv, | |
727 | .enqueue = h5_enqueue, | |
728 | .dequeue = h5_dequeue, | |
729 | .flush = h5_flush, | |
730 | }; | |
731 | ||
732 | int __init h5_init(void) | |
733 | { | |
734 | int err = hci_uart_register_proto(&h5p); | |
735 | ||
736 | if (!err) | |
737 | BT_INFO("HCI Three-wire UART (H5) protocol initialized"); | |
738 | else | |
739 | BT_ERR("HCI Three-wire UART (H5) protocol init failed"); | |
740 | ||
741 | return err; | |
742 | } | |
743 | ||
744 | int __exit h5_deinit(void) | |
745 | { | |
746 | return hci_uart_unregister_proto(&h5p); | |
747 | } |