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) | |
4223f368 | 54 | #define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4)) |
01977c0b | 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 | |
fa4cf04e | 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 | ||
618e8bc2 | 110 | hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT; |
f674a057 JH |
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 | { | |
afdc944c | 119 | /* Sliding window size (first 3 bits) */ |
742c5951 | 120 | return h5->tx_win & 0x07; |
afdc944c JH |
121 | } |
122 | ||
3f27e95b JH |
123 | static void h5_timed_event(unsigned long arg) |
124 | { | |
f674a057 | 125 | const unsigned char sync_req[] = { 0x01, 0x7e }; |
87a6b9bd | 126 | unsigned char conf_req[3] = { 0x03, 0xfc }; |
4a2fa2b8 | 127 | struct hci_uart *hu = (struct hci_uart *)arg; |
3f27e95b JH |
128 | struct h5 *h5 = hu->priv; |
129 | struct sk_buff *skb; | |
130 | unsigned long flags; | |
131 | ||
95c5c220 JH |
132 | BT_DBG("%s", hu->hdev->name); |
133 | ||
f674a057 JH |
134 | if (h5->state == H5_UNINITIALIZED) |
135 | h5_link_control(hu, sync_req, sizeof(sync_req)); | |
136 | ||
afdc944c JH |
137 | if (h5->state == H5_INITIALIZED) { |
138 | conf_req[2] = h5_cfg_field(h5); | |
f674a057 | 139 | h5_link_control(hu, conf_req, sizeof(conf_req)); |
afdc944c | 140 | } |
f674a057 JH |
141 | |
142 | if (h5->state != H5_ACTIVE) { | |
143 | mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); | |
144 | goto wakeup; | |
145 | } | |
146 | ||
95c5c220 JH |
147 | if (h5->sleep != H5_AWAKE) { |
148 | h5->sleep = H5_SLEEPING; | |
149 | goto wakeup; | |
150 | } | |
151 | ||
3f27e95b JH |
152 | BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen); |
153 | ||
154 | spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); | |
155 | ||
156 | while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) { | |
43eb12d7 | 157 | h5->tx_seq = (h5->tx_seq - 1) & 0x07; |
3f27e95b JH |
158 | skb_queue_head(&h5->rel, skb); |
159 | } | |
160 | ||
161 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
162 | ||
f674a057 | 163 | wakeup: |
3f27e95b JH |
164 | hci_uart_tx_wakeup(hu); |
165 | } | |
166 | ||
b509c02d LP |
167 | static void h5_peer_reset(struct hci_uart *hu) |
168 | { | |
169 | struct h5 *h5 = hu->priv; | |
b509c02d LP |
170 | |
171 | BT_ERR("Peer device has reset"); | |
172 | ||
173 | h5->state = H5_UNINITIALIZED; | |
174 | ||
175 | del_timer(&h5->timer); | |
176 | ||
177 | skb_queue_purge(&h5->rel); | |
178 | skb_queue_purge(&h5->unrel); | |
179 | skb_queue_purge(&h5->unack); | |
180 | ||
181 | h5->tx_seq = 0; | |
182 | h5->tx_ack = 0; | |
183 | ||
882809fb MH |
184 | /* Send reset request to upper stack */ |
185 | hci_reset_dev(hu->hdev); | |
b509c02d LP |
186 | } |
187 | ||
7dec65c8 JH |
188 | static int h5_open(struct hci_uart *hu) |
189 | { | |
7d664fba | 190 | struct h5 *h5; |
40f10224 | 191 | const unsigned char sync[] = { 0x01, 0x7e }; |
7d664fba JH |
192 | |
193 | BT_DBG("hu %p", hu); | |
194 | ||
195 | h5 = kzalloc(sizeof(*h5), GFP_KERNEL); | |
196 | if (!h5) | |
197 | return -ENOMEM; | |
198 | ||
199 | hu->priv = h5; | |
200 | ||
201 | skb_queue_head_init(&h5->unack); | |
202 | skb_queue_head_init(&h5->rel); | |
203 | skb_queue_head_init(&h5->unrel); | |
204 | ||
bc1f35b9 JH |
205 | h5_reset_rx(h5); |
206 | ||
3f27e95b JH |
207 | init_timer(&h5->timer); |
208 | h5->timer.function = h5_timed_event; | |
4a2fa2b8 | 209 | h5->timer.data = (unsigned long)hu; |
3f27e95b | 210 | |
afdc944c JH |
211 | h5->tx_win = H5_TX_WIN_MAX; |
212 | ||
cd1b4425 JH |
213 | set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags); |
214 | ||
40f10224 JH |
215 | /* Send initial sync request */ |
216 | h5_link_control(hu, sync, sizeof(sync)); | |
217 | mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); | |
218 | ||
7d664fba | 219 | return 0; |
7dec65c8 JH |
220 | } |
221 | ||
222 | static int h5_close(struct hci_uart *hu) | |
223 | { | |
7d664fba JH |
224 | struct h5 *h5 = hu->priv; |
225 | ||
c327cddd MK |
226 | del_timer_sync(&h5->timer); |
227 | ||
7d664fba JH |
228 | skb_queue_purge(&h5->unack); |
229 | skb_queue_purge(&h5->rel); | |
230 | skb_queue_purge(&h5->unrel); | |
231 | ||
232 | kfree(h5); | |
233 | ||
234 | return 0; | |
7dec65c8 JH |
235 | } |
236 | ||
43eb12d7 JH |
237 | static void h5_pkt_cull(struct h5 *h5) |
238 | { | |
239 | struct sk_buff *skb, *tmp; | |
240 | unsigned long flags; | |
241 | int i, to_remove; | |
242 | u8 seq; | |
243 | ||
244 | spin_lock_irqsave(&h5->unack.lock, flags); | |
245 | ||
246 | to_remove = skb_queue_len(&h5->unack); | |
40f10224 JH |
247 | if (to_remove == 0) |
248 | goto unlock; | |
43eb12d7 JH |
249 | |
250 | seq = h5->tx_seq; | |
251 | ||
252 | while (to_remove > 0) { | |
253 | if (h5->rx_ack == seq) | |
254 | break; | |
255 | ||
256 | to_remove--; | |
4807b518 | 257 | seq = (seq - 1) & 0x07; |
43eb12d7 JH |
258 | } |
259 | ||
260 | if (seq != h5->rx_ack) | |
261 | BT_ERR("Controller acked invalid packet"); | |
262 | ||
263 | i = 0; | |
264 | skb_queue_walk_safe(&h5->unack, skb, tmp) { | |
265 | if (i++ >= to_remove) | |
266 | break; | |
267 | ||
268 | __skb_unlink(skb, &h5->unack); | |
269 | kfree_skb(skb); | |
270 | } | |
271 | ||
272 | if (skb_queue_empty(&h5->unack)) | |
273 | del_timer(&h5->timer); | |
274 | ||
40f10224 | 275 | unlock: |
43eb12d7 JH |
276 | spin_unlock_irqrestore(&h5->unack.lock, flags); |
277 | } | |
278 | ||
bc1f35b9 JH |
279 | static void h5_handle_internal_rx(struct hci_uart *hu) |
280 | { | |
40f10224 JH |
281 | struct h5 *h5 = hu->priv; |
282 | const unsigned char sync_req[] = { 0x01, 0x7e }; | |
283 | const unsigned char sync_rsp[] = { 0x02, 0x7d }; | |
87a6b9bd | 284 | unsigned char conf_req[3] = { 0x03, 0xfc }; |
afdc944c | 285 | const unsigned char conf_rsp[] = { 0x04, 0x7b }; |
10122d07 JH |
286 | const unsigned char wakeup_req[] = { 0x05, 0xfa }; |
287 | const unsigned char woken_req[] = { 0x06, 0xf9 }; | |
288 | const unsigned char sleep_req[] = { 0x07, 0x78 }; | |
40f10224 JH |
289 | const unsigned char *hdr = h5->rx_skb->data; |
290 | const unsigned char *data = &h5->rx_skb->data[4]; | |
291 | ||
bc1f35b9 | 292 | BT_DBG("%s", hu->hdev->name); |
40f10224 JH |
293 | |
294 | if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) | |
295 | return; | |
296 | ||
297 | if (H5_HDR_LEN(hdr) < 2) | |
298 | return; | |
299 | ||
afdc944c JH |
300 | conf_req[2] = h5_cfg_field(h5); |
301 | ||
40f10224 | 302 | if (memcmp(data, sync_req, 2) == 0) { |
b509c02d LP |
303 | if (h5->state == H5_ACTIVE) |
304 | h5_peer_reset(hu); | |
40f10224 JH |
305 | h5_link_control(hu, sync_rsp, 2); |
306 | } else if (memcmp(data, sync_rsp, 2) == 0) { | |
b509c02d LP |
307 | if (h5->state == H5_ACTIVE) |
308 | h5_peer_reset(hu); | |
f674a057 | 309 | h5->state = H5_INITIALIZED; |
40f10224 JH |
310 | h5_link_control(hu, conf_req, 3); |
311 | } else if (memcmp(data, conf_req, 2) == 0) { | |
312 | h5_link_control(hu, conf_rsp, 2); | |
313 | h5_link_control(hu, conf_req, 3); | |
314 | } else if (memcmp(data, conf_rsp, 2) == 0) { | |
afdc944c | 315 | if (H5_HDR_LEN(hdr) > 2) |
1d3a1e69 | 316 | h5->tx_win = (data[2] & 0x07); |
afdc944c | 317 | BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win); |
f674a057 | 318 | h5->state = H5_ACTIVE; |
cd1b4425 | 319 | hci_uart_init_ready(hu); |
40f10224 | 320 | return; |
10122d07 JH |
321 | } else if (memcmp(data, sleep_req, 2) == 0) { |
322 | BT_DBG("Peer went to sleep"); | |
95c5c220 JH |
323 | h5->sleep = H5_SLEEPING; |
324 | return; | |
10122d07 JH |
325 | } else if (memcmp(data, woken_req, 2) == 0) { |
326 | BT_DBG("Peer woke up"); | |
95c5c220 JH |
327 | h5->sleep = H5_AWAKE; |
328 | } else if (memcmp(data, wakeup_req, 2) == 0) { | |
329 | BT_DBG("Peer requested wakeup"); | |
330 | h5_link_control(hu, woken_req, 2); | |
331 | h5->sleep = H5_AWAKE; | |
40f10224 JH |
332 | } else { |
333 | BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]); | |
334 | return; | |
335 | } | |
336 | ||
337 | hci_uart_tx_wakeup(hu); | |
bc1f35b9 JH |
338 | } |
339 | ||
340 | static void h5_complete_rx_pkt(struct hci_uart *hu) | |
341 | { | |
342 | struct h5 *h5 = hu->priv; | |
43eb12d7 | 343 | const unsigned char *hdr = h5->rx_skb->data; |
bc1f35b9 | 344 | |
43eb12d7 | 345 | if (H5_HDR_RELIABLE(hdr)) { |
40f10224 | 346 | h5->tx_ack = (h5->tx_ack + 1) % 8; |
e0482103 | 347 | set_bit(H5_TX_ACK_REQ, &h5->flags); |
40f10224 | 348 | hci_uart_tx_wakeup(hu); |
43eb12d7 | 349 | } |
bc1f35b9 | 350 | |
43eb12d7 JH |
351 | h5->rx_ack = H5_HDR_ACK(hdr); |
352 | ||
353 | h5_pkt_cull(h5); | |
354 | ||
355 | switch (H5_HDR_PKT_TYPE(hdr)) { | |
bc1f35b9 JH |
356 | case HCI_EVENT_PKT: |
357 | case HCI_ACLDATA_PKT: | |
358 | case HCI_SCODATA_PKT: | |
618e8bc2 | 359 | hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr); |
bc1f35b9 JH |
360 | |
361 | /* Remove Three-wire header */ | |
362 | skb_pull(h5->rx_skb, 4); | |
363 | ||
e1a26170 | 364 | hci_recv_frame(hu->hdev, h5->rx_skb); |
bc1f35b9 JH |
365 | h5->rx_skb = NULL; |
366 | ||
367 | break; | |
368 | ||
369 | default: | |
370 | h5_handle_internal_rx(hu); | |
371 | break; | |
372 | } | |
373 | ||
374 | h5_reset_rx(h5); | |
375 | } | |
376 | ||
377 | static int h5_rx_crc(struct hci_uart *hu, unsigned char c) | |
378 | { | |
bc1f35b9 | 379 | h5_complete_rx_pkt(hu); |
bc1f35b9 JH |
380 | |
381 | return 0; | |
382 | } | |
383 | ||
384 | static int h5_rx_payload(struct hci_uart *hu, unsigned char c) | |
385 | { | |
386 | struct h5 *h5 = hu->priv; | |
387 | const unsigned char *hdr = h5->rx_skb->data; | |
388 | ||
43eb12d7 | 389 | if (H5_HDR_CRC(hdr)) { |
bc1f35b9 JH |
390 | h5->rx_func = h5_rx_crc; |
391 | h5->rx_pending = 2; | |
392 | } else { | |
393 | h5_complete_rx_pkt(hu); | |
bc1f35b9 JH |
394 | } |
395 | ||
396 | return 0; | |
397 | } | |
398 | ||
399 | static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c) | |
400 | { | |
401 | struct h5 *h5 = hu->priv; | |
402 | const unsigned char *hdr = h5->rx_skb->data; | |
403 | ||
40f10224 JH |
404 | BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u", |
405 | hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), | |
406 | H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), | |
407 | H5_HDR_LEN(hdr)); | |
408 | ||
bc1f35b9 JH |
409 | if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) { |
410 | BT_ERR("Invalid header checksum"); | |
411 | h5_reset_rx(h5); | |
412 | return 0; | |
413 | } | |
414 | ||
40f10224 | 415 | if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) { |
43eb12d7 | 416 | BT_ERR("Out-of-order packet arrived (%u != %u)", |
40f10224 | 417 | H5_HDR_SEQ(hdr), h5->tx_ack); |
43eb12d7 JH |
418 | h5_reset_rx(h5); |
419 | return 0; | |
420 | } | |
421 | ||
f674a057 JH |
422 | if (h5->state != H5_ACTIVE && |
423 | H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) { | |
424 | BT_ERR("Non-link packet received in non-active state"); | |
425 | h5_reset_rx(h5); | |
48439d50 | 426 | return 0; |
f674a057 JH |
427 | } |
428 | ||
bc1f35b9 | 429 | h5->rx_func = h5_rx_payload; |
43eb12d7 | 430 | h5->rx_pending = H5_HDR_LEN(hdr); |
bc1f35b9 JH |
431 | |
432 | return 0; | |
433 | } | |
434 | ||
435 | static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c) | |
436 | { | |
437 | struct h5 *h5 = hu->priv; | |
438 | ||
bc1f35b9 JH |
439 | if (c == SLIP_DELIMITER) |
440 | return 1; | |
441 | ||
442 | h5->rx_func = h5_rx_3wire_hdr; | |
443 | h5->rx_pending = 4; | |
444 | ||
445 | h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC); | |
446 | if (!h5->rx_skb) { | |
447 | BT_ERR("Can't allocate mem for new packet"); | |
448 | h5_reset_rx(h5); | |
449 | return -ENOMEM; | |
450 | } | |
451 | ||
4a2fa2b8 | 452 | h5->rx_skb->dev = (void *)hu->hdev; |
bc1f35b9 JH |
453 | |
454 | return 0; | |
455 | } | |
456 | ||
457 | static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c) | |
458 | { | |
459 | struct h5 *h5 = hu->priv; | |
460 | ||
bc1f35b9 JH |
461 | if (c == SLIP_DELIMITER) |
462 | h5->rx_func = h5_rx_pkt_start; | |
463 | ||
464 | return 1; | |
465 | } | |
466 | ||
467 | static void h5_unslip_one_byte(struct h5 *h5, unsigned char c) | |
468 | { | |
469 | const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC; | |
470 | const u8 *byte = &c; | |
471 | ||
e0482103 JH |
472 | if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) { |
473 | set_bit(H5_RX_ESC, &h5->flags); | |
bc1f35b9 JH |
474 | return; |
475 | } | |
476 | ||
e0482103 | 477 | if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) { |
bc1f35b9 JH |
478 | switch (c) { |
479 | case SLIP_ESC_DELIM: | |
480 | byte = &delim; | |
481 | break; | |
482 | case SLIP_ESC_ESC: | |
483 | byte = &esc; | |
484 | break; | |
485 | default: | |
486 | BT_ERR("Invalid esc byte 0x%02hhx", c); | |
487 | h5_reset_rx(h5); | |
488 | return; | |
489 | } | |
bc1f35b9 JH |
490 | } |
491 | ||
492 | memcpy(skb_put(h5->rx_skb, 1), byte, 1); | |
493 | h5->rx_pending--; | |
494 | ||
255a68e0 | 495 | BT_DBG("unsliped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending); |
bc1f35b9 JH |
496 | } |
497 | ||
498 | static void h5_reset_rx(struct h5 *h5) | |
499 | { | |
500 | if (h5->rx_skb) { | |
501 | kfree_skb(h5->rx_skb); | |
502 | h5->rx_skb = NULL; | |
503 | } | |
504 | ||
505 | h5->rx_func = h5_rx_delimiter; | |
506 | h5->rx_pending = 0; | |
e0482103 | 507 | clear_bit(H5_RX_ESC, &h5->flags); |
bc1f35b9 JH |
508 | } |
509 | ||
9d1c40eb | 510 | static int h5_recv(struct hci_uart *hu, const void *data, int count) |
7dec65c8 | 511 | { |
bc1f35b9 | 512 | struct h5 *h5 = hu->priv; |
9d1c40eb | 513 | const unsigned char *ptr = data; |
bc1f35b9 | 514 | |
255a68e0 JH |
515 | BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending, |
516 | count); | |
bc1f35b9 JH |
517 | |
518 | while (count > 0) { | |
519 | int processed; | |
520 | ||
521 | if (h5->rx_pending > 0) { | |
522 | if (*ptr == SLIP_DELIMITER) { | |
523 | BT_ERR("Too short H5 packet"); | |
524 | h5_reset_rx(h5); | |
525 | continue; | |
526 | } | |
527 | ||
528 | h5_unslip_one_byte(h5, *ptr); | |
529 | ||
530 | ptr++; count--; | |
531 | continue; | |
532 | } | |
533 | ||
534 | processed = h5->rx_func(hu, *ptr); | |
535 | if (processed < 0) | |
536 | return processed; | |
537 | ||
538 | ptr += processed; | |
539 | count -= processed; | |
540 | } | |
541 | ||
542 | return 0; | |
7dec65c8 JH |
543 | } |
544 | ||
545 | static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) | |
546 | { | |
7d664fba JH |
547 | struct h5 *h5 = hu->priv; |
548 | ||
549 | if (skb->len > 0xfff) { | |
550 | BT_ERR("Packet too long (%u bytes)", skb->len); | |
551 | kfree_skb(skb); | |
552 | return 0; | |
553 | } | |
554 | ||
f674a057 JH |
555 | if (h5->state != H5_ACTIVE) { |
556 | BT_ERR("Ignoring HCI data in non-active state"); | |
557 | kfree_skb(skb); | |
558 | return 0; | |
559 | } | |
560 | ||
618e8bc2 | 561 | switch (hci_skb_pkt_type(skb)) { |
7d664fba JH |
562 | case HCI_ACLDATA_PKT: |
563 | case HCI_COMMAND_PKT: | |
564 | skb_queue_tail(&h5->rel, skb); | |
565 | break; | |
566 | ||
567 | case HCI_SCODATA_PKT: | |
568 | skb_queue_tail(&h5->unrel, skb); | |
569 | break; | |
570 | ||
571 | default: | |
618e8bc2 | 572 | BT_ERR("Unknown packet type %u", hci_skb_pkt_type(skb)); |
7d664fba JH |
573 | kfree_skb(skb); |
574 | break; | |
575 | } | |
576 | ||
577 | return 0; | |
578 | } | |
579 | ||
c0a1b73c JH |
580 | static void h5_slip_delim(struct sk_buff *skb) |
581 | { | |
582 | const char delim = SLIP_DELIMITER; | |
583 | ||
584 | memcpy(skb_put(skb, 1), &delim, 1); | |
585 | } | |
586 | ||
587 | static void h5_slip_one_byte(struct sk_buff *skb, u8 c) | |
588 | { | |
589 | const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM }; | |
590 | const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC }; | |
591 | ||
592 | switch (c) { | |
593 | case SLIP_DELIMITER: | |
594 | memcpy(skb_put(skb, 2), &esc_delim, 2); | |
595 | break; | |
596 | case SLIP_ESC: | |
597 | memcpy(skb_put(skb, 2), &esc_esc, 2); | |
598 | break; | |
599 | default: | |
600 | memcpy(skb_put(skb, 1), &c, 1); | |
601 | } | |
602 | } | |
603 | ||
c826ed09 JH |
604 | static bool valid_packet_type(u8 type) |
605 | { | |
606 | switch (type) { | |
607 | case HCI_ACLDATA_PKT: | |
608 | case HCI_COMMAND_PKT: | |
609 | case HCI_SCODATA_PKT: | |
610 | case HCI_3WIRE_LINK_PKT: | |
611 | case HCI_3WIRE_ACK_PKT: | |
612 | return true; | |
613 | default: | |
614 | return false; | |
615 | } | |
616 | } | |
617 | ||
618 | static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type, | |
619 | const u8 *data, size_t len) | |
7d664fba | 620 | { |
40f10224 | 621 | struct h5 *h5 = hu->priv; |
c0a1b73c JH |
622 | struct sk_buff *nskb; |
623 | u8 hdr[4]; | |
624 | int i; | |
625 | ||
c826ed09 JH |
626 | if (!valid_packet_type(pkt_type)) { |
627 | BT_ERR("Unknown packet type %u", pkt_type); | |
628 | return NULL; | |
629 | } | |
630 | ||
c0a1b73c JH |
631 | /* |
632 | * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2 | |
633 | * (because bytes 0xc0 and 0xdb are escaped, worst case is when | |
634 | * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0 | |
635 | * delimiters at start and end). | |
636 | */ | |
637 | nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC); | |
638 | if (!nskb) | |
639 | return NULL; | |
640 | ||
618e8bc2 | 641 | hci_skb_pkt_type(nskb) = pkt_type; |
c0a1b73c JH |
642 | |
643 | h5_slip_delim(nskb); | |
644 | ||
40f10224 | 645 | hdr[0] = h5->tx_ack << 3; |
e0482103 | 646 | clear_bit(H5_TX_ACK_REQ, &h5->flags); |
c0a1b73c | 647 | |
c826ed09 JH |
648 | /* Reliable packet? */ |
649 | if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) { | |
c0a1b73c | 650 | hdr[0] |= 1 << 7; |
43eb12d7 JH |
651 | hdr[0] |= h5->tx_seq; |
652 | h5->tx_seq = (h5->tx_seq + 1) % 8; | |
c0a1b73c JH |
653 | } |
654 | ||
655 | hdr[1] = pkt_type | ((len & 0x0f) << 4); | |
656 | hdr[2] = len >> 4; | |
657 | hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff); | |
658 | ||
40f10224 JH |
659 | BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u", |
660 | hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), | |
661 | H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), | |
662 | H5_HDR_LEN(hdr)); | |
663 | ||
c0a1b73c JH |
664 | for (i = 0; i < 4; i++) |
665 | h5_slip_one_byte(nskb, hdr[i]); | |
666 | ||
667 | for (i = 0; i < len; i++) | |
668 | h5_slip_one_byte(nskb, data[i]); | |
669 | ||
670 | h5_slip_delim(nskb); | |
671 | ||
672 | return nskb; | |
673 | } | |
674 | ||
7dec65c8 JH |
675 | static struct sk_buff *h5_dequeue(struct hci_uart *hu) |
676 | { | |
7d664fba | 677 | struct h5 *h5 = hu->priv; |
3f27e95b | 678 | unsigned long flags; |
7d664fba JH |
679 | struct sk_buff *skb, *nskb; |
680 | ||
95c5c220 JH |
681 | if (h5->sleep != H5_AWAKE) { |
682 | const unsigned char wakeup_req[] = { 0x05, 0xfa }; | |
683 | ||
684 | if (h5->sleep == H5_WAKING_UP) | |
685 | return NULL; | |
686 | ||
687 | h5->sleep = H5_WAKING_UP; | |
688 | BT_DBG("Sending wakeup request"); | |
689 | ||
690 | mod_timer(&h5->timer, jiffies + HZ / 100); | |
691 | return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2); | |
692 | } | |
693 | ||
a08b15e6 | 694 | skb = skb_dequeue(&h5->unrel); |
4a2fa2b8 | 695 | if (skb) { |
618e8bc2 | 696 | nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), |
c0a1b73c | 697 | skb->data, skb->len); |
7d664fba JH |
698 | if (nskb) { |
699 | kfree_skb(skb); | |
700 | return nskb; | |
701 | } | |
702 | ||
703 | skb_queue_head(&h5->unrel, skb); | |
704 | BT_ERR("Could not dequeue pkt because alloc_skb failed"); | |
705 | } | |
706 | ||
3f27e95b JH |
707 | spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); |
708 | ||
afdc944c | 709 | if (h5->unack.qlen >= h5->tx_win) |
3f27e95b JH |
710 | goto unlock; |
711 | ||
a08b15e6 | 712 | skb = skb_dequeue(&h5->rel); |
4a2fa2b8 | 713 | if (skb) { |
618e8bc2 | 714 | nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), |
c0a1b73c | 715 | skb->data, skb->len); |
3f27e95b JH |
716 | if (nskb) { |
717 | __skb_queue_tail(&h5->unack, skb); | |
718 | mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT); | |
719 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
720 | return nskb; | |
721 | } | |
722 | ||
723 | skb_queue_head(&h5->rel, skb); | |
724 | BT_ERR("Could not dequeue pkt because alloc_skb failed"); | |
725 | } | |
726 | ||
727 | unlock: | |
728 | spin_unlock_irqrestore(&h5->unack.lock, flags); | |
729 | ||
e0482103 | 730 | if (test_bit(H5_TX_ACK_REQ, &h5->flags)) |
40f10224 | 731 | return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0); |
7d664fba | 732 | |
7dec65c8 JH |
733 | return NULL; |
734 | } | |
735 | ||
736 | static int h5_flush(struct hci_uart *hu) | |
737 | { | |
7d664fba JH |
738 | BT_DBG("hu %p", hu); |
739 | return 0; | |
7dec65c8 JH |
740 | } |
741 | ||
4ee7ef19 | 742 | static const struct hci_uart_proto h5p = { |
7dec65c8 | 743 | .id = HCI_UART_3WIRE, |
7c40fb8d | 744 | .name = "Three-wire (H5)", |
7dec65c8 JH |
745 | .open = h5_open, |
746 | .close = h5_close, | |
747 | .recv = h5_recv, | |
748 | .enqueue = h5_enqueue, | |
749 | .dequeue = h5_dequeue, | |
750 | .flush = h5_flush, | |
751 | }; | |
752 | ||
753 | int __init h5_init(void) | |
754 | { | |
01009eec | 755 | return hci_uart_register_proto(&h5p); |
7dec65c8 JH |
756 | } |
757 | ||
758 | int __exit h5_deinit(void) | |
759 | { | |
760 | return hci_uart_unregister_proto(&h5p); | |
761 | } |