]>
Commit | Line | Data |
---|---|---|
f2ab3298 BA |
1 | /* |
2 | * Copyright (c) 2015, Sony Mobile Communications AB. | |
3 | * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 and | |
7 | * only version 2 as published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | */ | |
14 | ||
15 | #include <linux/interrupt.h> | |
16 | #include <linux/io.h> | |
17 | #include <linux/mfd/syscon.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/of_irq.h> | |
20 | #include <linux/of_platform.h> | |
21 | #include <linux/platform_device.h> | |
22 | #include <linux/regmap.h> | |
23 | #include <linux/sched.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/soc/qcom/smd.h> | |
26 | #include <linux/soc/qcom/smem.h> | |
27 | #include <linux/wait.h> | |
28 | ||
29 | /* | |
30 | * The Qualcomm Shared Memory communication solution provides point-to-point | |
31 | * channels for clients to send and receive streaming or packet based data. | |
32 | * | |
33 | * Each channel consists of a control item (channel info) and a ring buffer | |
34 | * pair. The channel info carry information related to channel state, flow | |
35 | * control and the offsets within the ring buffer. | |
36 | * | |
37 | * All allocated channels are listed in an allocation table, identifying the | |
38 | * pair of items by name, type and remote processor. | |
39 | * | |
40 | * Upon creating a new channel the remote processor allocates channel info and | |
41 | * ring buffer items from the smem heap and populate the allocation table. An | |
42 | * interrupt is sent to the other end of the channel and a scan for new | |
43 | * channels should be done. A channel never goes away, it will only change | |
44 | * state. | |
45 | * | |
46 | * The remote processor signals it intent for bring up the communication | |
47 | * channel by setting the state of its end of the channel to "opening" and | |
48 | * sends out an interrupt. We detect this change and register a smd device to | |
49 | * consume the channel. Upon finding a consumer we finish the handshake and the | |
50 | * channel is up. | |
51 | * | |
52 | * Upon closing a channel, the remote processor will update the state of its | |
53 | * end of the channel and signal us, we will then unregister any attached | |
54 | * device and close our end of the channel. | |
55 | * | |
56 | * Devices attached to a channel can use the qcom_smd_send function to push | |
57 | * data to the channel, this is done by copying the data into the tx ring | |
58 | * buffer, updating the pointers in the channel info and signaling the remote | |
59 | * processor. | |
60 | * | |
61 | * The remote processor does the equivalent when it transfer data and upon | |
62 | * receiving the interrupt we check the channel info for new data and delivers | |
63 | * this to the attached device. If the device is not ready to receive the data | |
64 | * we leave it in the ring buffer for now. | |
65 | */ | |
66 | ||
67 | struct smd_channel_info; | |
f02dc825 | 68 | struct smd_channel_info_pair; |
f2ab3298 | 69 | struct smd_channel_info_word; |
f02dc825 | 70 | struct smd_channel_info_word_pair; |
f2ab3298 BA |
71 | |
72 | #define SMD_ALLOC_TBL_COUNT 2 | |
73 | #define SMD_ALLOC_TBL_SIZE 64 | |
74 | ||
75 | /* | |
76 | * This lists the various smem heap items relevant for the allocation table and | |
77 | * smd channel entries. | |
78 | */ | |
79 | static const struct { | |
80 | unsigned alloc_tbl_id; | |
81 | unsigned info_base_id; | |
82 | unsigned fifo_base_id; | |
83 | } smem_items[SMD_ALLOC_TBL_COUNT] = { | |
84 | { | |
85 | .alloc_tbl_id = 13, | |
86 | .info_base_id = 14, | |
87 | .fifo_base_id = 338 | |
88 | }, | |
89 | { | |
ea4683e0 BA |
90 | .alloc_tbl_id = 266, |
91 | .info_base_id = 138, | |
f2ab3298 BA |
92 | .fifo_base_id = 202, |
93 | }, | |
94 | }; | |
95 | ||
96 | /** | |
97 | * struct qcom_smd_edge - representing a remote processor | |
98 | * @smd: handle to qcom_smd | |
99 | * @of_node: of_node handle for information related to this edge | |
100 | * @edge_id: identifier of this edge | |
93dbed91 | 101 | * @remote_pid: identifier of remote processor |
f2ab3298 BA |
102 | * @irq: interrupt for signals on this edge |
103 | * @ipc_regmap: regmap handle holding the outgoing ipc register | |
104 | * @ipc_offset: offset within @ipc_regmap of the register for ipc | |
105 | * @ipc_bit: bit in the register at @ipc_offset of @ipc_regmap | |
106 | * @channels: list of all channels detected on this edge | |
107 | * @channels_lock: guard for modifications of @channels | |
108 | * @allocated: array of bitmaps representing already allocated channels | |
f2ab3298 | 109 | * @smem_available: last available amount of smem triggering a channel scan |
995b170a BA |
110 | * @scan_work: work item for discovering new channels |
111 | * @state_work: work item for edge state changes | |
f2ab3298 BA |
112 | */ |
113 | struct qcom_smd_edge { | |
114 | struct qcom_smd *smd; | |
115 | struct device_node *of_node; | |
116 | unsigned edge_id; | |
93dbed91 | 117 | unsigned remote_pid; |
f2ab3298 BA |
118 | |
119 | int irq; | |
120 | ||
121 | struct regmap *ipc_regmap; | |
122 | int ipc_offset; | |
123 | int ipc_bit; | |
124 | ||
125 | struct list_head channels; | |
126 | spinlock_t channels_lock; | |
127 | ||
128 | DECLARE_BITMAP(allocated[SMD_ALLOC_TBL_COUNT], SMD_ALLOC_TBL_SIZE); | |
129 | ||
f2ab3298 BA |
130 | unsigned smem_available; |
131 | ||
028021d2 BA |
132 | wait_queue_head_t new_channel_event; |
133 | ||
995b170a BA |
134 | struct work_struct scan_work; |
135 | struct work_struct state_work; | |
f2ab3298 BA |
136 | }; |
137 | ||
138 | /* | |
139 | * SMD channel states. | |
140 | */ | |
141 | enum smd_channel_state { | |
142 | SMD_CHANNEL_CLOSED, | |
143 | SMD_CHANNEL_OPENING, | |
144 | SMD_CHANNEL_OPENED, | |
145 | SMD_CHANNEL_FLUSHING, | |
146 | SMD_CHANNEL_CLOSING, | |
147 | SMD_CHANNEL_RESET, | |
148 | SMD_CHANNEL_RESET_OPENING | |
149 | }; | |
150 | ||
151 | /** | |
152 | * struct qcom_smd_channel - smd channel struct | |
153 | * @edge: qcom_smd_edge this channel is living on | |
154 | * @qsdev: reference to a associated smd client device | |
155 | * @name: name of the channel | |
156 | * @state: local state of the channel | |
157 | * @remote_state: remote state of the channel | |
f02dc825 SB |
158 | * @info: byte aligned outgoing/incoming channel info |
159 | * @info_word: word aligned outgoing/incoming channel info | |
f2ab3298 BA |
160 | * @tx_lock: lock to make writes to the channel mutually exclusive |
161 | * @fblockread_event: wakeup event tied to tx fBLOCKREADINTR | |
162 | * @tx_fifo: pointer to the outgoing ring buffer | |
163 | * @rx_fifo: pointer to the incoming ring buffer | |
164 | * @fifo_size: size of each ring buffer | |
165 | * @bounce_buffer: bounce buffer for reading wrapped packets | |
166 | * @cb: callback function registered for this channel | |
167 | * @recv_lock: guard for rx info modifications and cb pointer | |
168 | * @pkt_size: size of the currently handled packet | |
169 | * @list: lite entry for @channels in qcom_smd_edge | |
170 | */ | |
171 | struct qcom_smd_channel { | |
172 | struct qcom_smd_edge *edge; | |
173 | ||
174 | struct qcom_smd_device *qsdev; | |
175 | ||
176 | char *name; | |
177 | enum smd_channel_state state; | |
178 | enum smd_channel_state remote_state; | |
179 | ||
f02dc825 SB |
180 | struct smd_channel_info_pair *info; |
181 | struct smd_channel_info_word_pair *info_word; | |
f2ab3298 BA |
182 | |
183 | struct mutex tx_lock; | |
184 | wait_queue_head_t fblockread_event; | |
185 | ||
186 | void *tx_fifo; | |
187 | void *rx_fifo; | |
188 | int fifo_size; | |
189 | ||
190 | void *bounce_buffer; | |
39f0db29 | 191 | qcom_smd_cb_t cb; |
f2ab3298 BA |
192 | |
193 | spinlock_t recv_lock; | |
194 | ||
195 | int pkt_size; | |
196 | ||
b853cb96 BA |
197 | void *drvdata; |
198 | ||
f2ab3298 | 199 | struct list_head list; |
d5933855 | 200 | struct list_head dev_list; |
f2ab3298 BA |
201 | }; |
202 | ||
203 | /** | |
204 | * struct qcom_smd - smd struct | |
205 | * @dev: device struct | |
206 | * @num_edges: number of entries in @edges | |
207 | * @edges: array of edges to be handled | |
208 | */ | |
209 | struct qcom_smd { | |
210 | struct device *dev; | |
211 | ||
212 | unsigned num_edges; | |
213 | struct qcom_smd_edge edges[0]; | |
214 | }; | |
215 | ||
216 | /* | |
217 | * Format of the smd_info smem items, for byte aligned channels. | |
218 | */ | |
219 | struct smd_channel_info { | |
24f60e37 | 220 | __le32 state; |
f2ab3298 BA |
221 | u8 fDSR; |
222 | u8 fCTS; | |
223 | u8 fCD; | |
224 | u8 fRI; | |
225 | u8 fHEAD; | |
226 | u8 fTAIL; | |
227 | u8 fSTATE; | |
228 | u8 fBLOCKREADINTR; | |
24f60e37 SB |
229 | __le32 tail; |
230 | __le32 head; | |
f2ab3298 BA |
231 | }; |
232 | ||
f02dc825 SB |
233 | struct smd_channel_info_pair { |
234 | struct smd_channel_info tx; | |
235 | struct smd_channel_info rx; | |
236 | }; | |
237 | ||
f2ab3298 BA |
238 | /* |
239 | * Format of the smd_info smem items, for word aligned channels. | |
240 | */ | |
241 | struct smd_channel_info_word { | |
24f60e37 SB |
242 | __le32 state; |
243 | __le32 fDSR; | |
244 | __le32 fCTS; | |
245 | __le32 fCD; | |
246 | __le32 fRI; | |
247 | __le32 fHEAD; | |
248 | __le32 fTAIL; | |
249 | __le32 fSTATE; | |
250 | __le32 fBLOCKREADINTR; | |
251 | __le32 tail; | |
252 | __le32 head; | |
f2ab3298 BA |
253 | }; |
254 | ||
f02dc825 SB |
255 | struct smd_channel_info_word_pair { |
256 | struct smd_channel_info_word tx; | |
257 | struct smd_channel_info_word rx; | |
258 | }; | |
259 | ||
24f60e37 SB |
260 | #define GET_RX_CHANNEL_FLAG(channel, param) \ |
261 | ({ \ | |
262 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \ | |
263 | channel->info_word ? \ | |
264 | le32_to_cpu(channel->info_word->rx.param) : \ | |
265 | channel->info->rx.param; \ | |
266 | }) | |
267 | ||
268 | #define GET_RX_CHANNEL_INFO(channel, param) \ | |
269 | ({ \ | |
270 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \ | |
271 | le32_to_cpu(channel->info_word ? \ | |
272 | channel->info_word->rx.param : \ | |
273 | channel->info->rx.param); \ | |
274 | }) | |
275 | ||
276 | #define SET_RX_CHANNEL_FLAG(channel, param, value) \ | |
277 | ({ \ | |
278 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \ | |
279 | if (channel->info_word) \ | |
280 | channel->info_word->rx.param = cpu_to_le32(value); \ | |
281 | else \ | |
282 | channel->info->rx.param = value; \ | |
283 | }) | |
284 | ||
285 | #define SET_RX_CHANNEL_INFO(channel, param, value) \ | |
286 | ({ \ | |
287 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \ | |
288 | if (channel->info_word) \ | |
289 | channel->info_word->rx.param = cpu_to_le32(value); \ | |
290 | else \ | |
291 | channel->info->rx.param = cpu_to_le32(value); \ | |
292 | }) | |
293 | ||
294 | #define GET_TX_CHANNEL_FLAG(channel, param) \ | |
295 | ({ \ | |
296 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \ | |
297 | channel->info_word ? \ | |
298 | le32_to_cpu(channel->info_word->tx.param) : \ | |
299 | channel->info->tx.param; \ | |
300 | }) | |
301 | ||
302 | #define GET_TX_CHANNEL_INFO(channel, param) \ | |
303 | ({ \ | |
304 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \ | |
305 | le32_to_cpu(channel->info_word ? \ | |
306 | channel->info_word->tx.param : \ | |
307 | channel->info->tx.param); \ | |
308 | }) | |
309 | ||
310 | #define SET_TX_CHANNEL_FLAG(channel, param, value) \ | |
311 | ({ \ | |
312 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \ | |
313 | if (channel->info_word) \ | |
314 | channel->info_word->tx.param = cpu_to_le32(value); \ | |
315 | else \ | |
316 | channel->info->tx.param = value; \ | |
317 | }) | |
318 | ||
319 | #define SET_TX_CHANNEL_INFO(channel, param, value) \ | |
320 | ({ \ | |
321 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \ | |
322 | if (channel->info_word) \ | |
323 | channel->info_word->tx.param = cpu_to_le32(value); \ | |
324 | else \ | |
325 | channel->info->tx.param = cpu_to_le32(value); \ | |
326 | }) | |
f2ab3298 BA |
327 | |
328 | /** | |
329 | * struct qcom_smd_alloc_entry - channel allocation entry | |
330 | * @name: channel name | |
331 | * @cid: channel index | |
332 | * @flags: channel flags and edge id | |
333 | * @ref_count: reference count of the channel | |
334 | */ | |
335 | struct qcom_smd_alloc_entry { | |
336 | u8 name[20]; | |
24f60e37 SB |
337 | __le32 cid; |
338 | __le32 flags; | |
339 | __le32 ref_count; | |
f2ab3298 BA |
340 | } __packed; |
341 | ||
342 | #define SMD_CHANNEL_FLAGS_EDGE_MASK 0xff | |
343 | #define SMD_CHANNEL_FLAGS_STREAM BIT(8) | |
344 | #define SMD_CHANNEL_FLAGS_PACKET BIT(9) | |
345 | ||
346 | /* | |
347 | * Each smd packet contains a 20 byte header, with the first 4 being the length | |
348 | * of the packet. | |
349 | */ | |
350 | #define SMD_PACKET_HEADER_LEN 20 | |
351 | ||
352 | /* | |
353 | * Signal the remote processor associated with 'channel'. | |
354 | */ | |
355 | static void qcom_smd_signal_channel(struct qcom_smd_channel *channel) | |
356 | { | |
357 | struct qcom_smd_edge *edge = channel->edge; | |
358 | ||
359 | regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit)); | |
360 | } | |
361 | ||
362 | /* | |
363 | * Initialize the tx channel info | |
364 | */ | |
365 | static void qcom_smd_channel_reset(struct qcom_smd_channel *channel) | |
366 | { | |
367 | SET_TX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED); | |
24f60e37 SB |
368 | SET_TX_CHANNEL_FLAG(channel, fDSR, 0); |
369 | SET_TX_CHANNEL_FLAG(channel, fCTS, 0); | |
370 | SET_TX_CHANNEL_FLAG(channel, fCD, 0); | |
371 | SET_TX_CHANNEL_FLAG(channel, fRI, 0); | |
372 | SET_TX_CHANNEL_FLAG(channel, fHEAD, 0); | |
373 | SET_TX_CHANNEL_FLAG(channel, fTAIL, 0); | |
374 | SET_TX_CHANNEL_FLAG(channel, fSTATE, 1); | |
375 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1); | |
f2ab3298 BA |
376 | SET_TX_CHANNEL_INFO(channel, head, 0); |
377 | SET_TX_CHANNEL_INFO(channel, tail, 0); | |
378 | ||
379 | qcom_smd_signal_channel(channel); | |
380 | ||
381 | channel->state = SMD_CHANNEL_CLOSED; | |
382 | channel->pkt_size = 0; | |
383 | } | |
384 | ||
39f0db29 BA |
385 | /* |
386 | * Set the callback for a channel, with appropriate locking | |
387 | */ | |
388 | static void qcom_smd_channel_set_callback(struct qcom_smd_channel *channel, | |
389 | qcom_smd_cb_t cb) | |
390 | { | |
391 | unsigned long flags; | |
392 | ||
393 | spin_lock_irqsave(&channel->recv_lock, flags); | |
394 | channel->cb = cb; | |
395 | spin_unlock_irqrestore(&channel->recv_lock, flags); | |
396 | }; | |
397 | ||
f2ab3298 BA |
398 | /* |
399 | * Calculate the amount of data available in the rx fifo | |
400 | */ | |
401 | static size_t qcom_smd_channel_get_rx_avail(struct qcom_smd_channel *channel) | |
402 | { | |
403 | unsigned head; | |
404 | unsigned tail; | |
405 | ||
406 | head = GET_RX_CHANNEL_INFO(channel, head); | |
407 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
408 | ||
409 | return (head - tail) & (channel->fifo_size - 1); | |
410 | } | |
411 | ||
412 | /* | |
413 | * Set tx channel state and inform the remote processor | |
414 | */ | |
415 | static void qcom_smd_channel_set_state(struct qcom_smd_channel *channel, | |
416 | int state) | |
417 | { | |
418 | struct qcom_smd_edge *edge = channel->edge; | |
419 | bool is_open = state == SMD_CHANNEL_OPENED; | |
420 | ||
421 | if (channel->state == state) | |
422 | return; | |
423 | ||
424 | dev_dbg(edge->smd->dev, "set_state(%s, %d)\n", channel->name, state); | |
425 | ||
24f60e37 SB |
426 | SET_TX_CHANNEL_FLAG(channel, fDSR, is_open); |
427 | SET_TX_CHANNEL_FLAG(channel, fCTS, is_open); | |
428 | SET_TX_CHANNEL_FLAG(channel, fCD, is_open); | |
f2ab3298 BA |
429 | |
430 | SET_TX_CHANNEL_INFO(channel, state, state); | |
24f60e37 | 431 | SET_TX_CHANNEL_FLAG(channel, fSTATE, 1); |
f2ab3298 BA |
432 | |
433 | channel->state = state; | |
434 | qcom_smd_signal_channel(channel); | |
435 | } | |
436 | ||
437 | /* | |
438 | * Copy count bytes of data using 32bit accesses, if that's required. | |
439 | */ | |
3b781e55 SB |
440 | static void smd_copy_to_fifo(void __iomem *dst, |
441 | const void *src, | |
f2ab3298 BA |
442 | size_t count, |
443 | bool word_aligned) | |
444 | { | |
f2ab3298 | 445 | if (word_aligned) { |
3b781e55 | 446 | __iowrite32_copy(dst, src, count / sizeof(u32)); |
f2ab3298 | 447 | } else { |
3b781e55 | 448 | memcpy_toio(dst, src, count); |
f2ab3298 BA |
449 | } |
450 | } | |
451 | ||
452 | /* | |
453 | * Copy count bytes of data using 32bit accesses, if that is required. | |
454 | */ | |
c431e678 SB |
455 | static void smd_copy_from_fifo(void *dst, |
456 | const void __iomem *src, | |
f2ab3298 BA |
457 | size_t count, |
458 | bool word_aligned) | |
459 | { | |
f2ab3298 | 460 | if (word_aligned) { |
c431e678 | 461 | __ioread32_copy(dst, src, count / sizeof(u32)); |
f2ab3298 | 462 | } else { |
c431e678 | 463 | memcpy_fromio(dst, src, count); |
f2ab3298 BA |
464 | } |
465 | } | |
466 | ||
467 | /* | |
468 | * Read count bytes of data from the rx fifo into buf, but don't advance the | |
469 | * tail. | |
470 | */ | |
471 | static size_t qcom_smd_channel_peek(struct qcom_smd_channel *channel, | |
472 | void *buf, size_t count) | |
473 | { | |
474 | bool word_aligned; | |
475 | unsigned tail; | |
476 | size_t len; | |
477 | ||
f02dc825 | 478 | word_aligned = channel->info_word; |
f2ab3298 BA |
479 | tail = GET_RX_CHANNEL_INFO(channel, tail); |
480 | ||
481 | len = min_t(size_t, count, channel->fifo_size - tail); | |
482 | if (len) { | |
483 | smd_copy_from_fifo(buf, | |
484 | channel->rx_fifo + tail, | |
485 | len, | |
486 | word_aligned); | |
487 | } | |
488 | ||
489 | if (len != count) { | |
490 | smd_copy_from_fifo(buf + len, | |
491 | channel->rx_fifo, | |
492 | count - len, | |
493 | word_aligned); | |
494 | } | |
495 | ||
496 | return count; | |
497 | } | |
498 | ||
499 | /* | |
500 | * Advance the rx tail by count bytes. | |
501 | */ | |
502 | static void qcom_smd_channel_advance(struct qcom_smd_channel *channel, | |
503 | size_t count) | |
504 | { | |
505 | unsigned tail; | |
506 | ||
507 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
508 | tail += count; | |
509 | tail &= (channel->fifo_size - 1); | |
510 | SET_RX_CHANNEL_INFO(channel, tail, tail); | |
511 | } | |
512 | ||
513 | /* | |
514 | * Read out a single packet from the rx fifo and deliver it to the device | |
515 | */ | |
516 | static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel) | |
517 | { | |
f2ab3298 BA |
518 | unsigned tail; |
519 | size_t len; | |
520 | void *ptr; | |
521 | int ret; | |
522 | ||
523 | if (!channel->cb) | |
524 | return 0; | |
525 | ||
526 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
527 | ||
528 | /* Use bounce buffer if the data wraps */ | |
529 | if (tail + channel->pkt_size >= channel->fifo_size) { | |
530 | ptr = channel->bounce_buffer; | |
531 | len = qcom_smd_channel_peek(channel, ptr, channel->pkt_size); | |
532 | } else { | |
533 | ptr = channel->rx_fifo + tail; | |
534 | len = channel->pkt_size; | |
535 | } | |
536 | ||
b853cb96 | 537 | ret = channel->cb(channel, ptr, len); |
f2ab3298 BA |
538 | if (ret < 0) |
539 | return ret; | |
540 | ||
541 | /* Only forward the tail if the client consumed the data */ | |
542 | qcom_smd_channel_advance(channel, len); | |
543 | ||
544 | channel->pkt_size = 0; | |
545 | ||
546 | return 0; | |
547 | } | |
548 | ||
549 | /* | |
550 | * Per channel interrupt handling | |
551 | */ | |
552 | static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel) | |
553 | { | |
554 | bool need_state_scan = false; | |
555 | int remote_state; | |
24f60e37 | 556 | __le32 pktlen; |
f2ab3298 BA |
557 | int avail; |
558 | int ret; | |
559 | ||
560 | /* Handle state changes */ | |
561 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
562 | if (remote_state != channel->remote_state) { | |
563 | channel->remote_state = remote_state; | |
564 | need_state_scan = true; | |
565 | } | |
566 | /* Indicate that we have seen any state change */ | |
24f60e37 | 567 | SET_RX_CHANNEL_FLAG(channel, fSTATE, 0); |
f2ab3298 BA |
568 | |
569 | /* Signal waiting qcom_smd_send() about the interrupt */ | |
24f60e37 | 570 | if (!GET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) |
f2ab3298 BA |
571 | wake_up_interruptible(&channel->fblockread_event); |
572 | ||
573 | /* Don't consume any data until we've opened the channel */ | |
574 | if (channel->state != SMD_CHANNEL_OPENED) | |
575 | goto out; | |
576 | ||
577 | /* Indicate that we've seen the new data */ | |
24f60e37 | 578 | SET_RX_CHANNEL_FLAG(channel, fHEAD, 0); |
f2ab3298 BA |
579 | |
580 | /* Consume data */ | |
581 | for (;;) { | |
582 | avail = qcom_smd_channel_get_rx_avail(channel); | |
583 | ||
584 | if (!channel->pkt_size && avail >= SMD_PACKET_HEADER_LEN) { | |
585 | qcom_smd_channel_peek(channel, &pktlen, sizeof(pktlen)); | |
586 | qcom_smd_channel_advance(channel, SMD_PACKET_HEADER_LEN); | |
24f60e37 | 587 | channel->pkt_size = le32_to_cpu(pktlen); |
f2ab3298 BA |
588 | } else if (channel->pkt_size && avail >= channel->pkt_size) { |
589 | ret = qcom_smd_channel_recv_single(channel); | |
590 | if (ret) | |
591 | break; | |
592 | } else { | |
593 | break; | |
594 | } | |
595 | } | |
596 | ||
597 | /* Indicate that we have seen and updated tail */ | |
24f60e37 | 598 | SET_RX_CHANNEL_FLAG(channel, fTAIL, 1); |
f2ab3298 BA |
599 | |
600 | /* Signal the remote that we've consumed the data (if requested) */ | |
24f60e37 | 601 | if (!GET_RX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) { |
f2ab3298 BA |
602 | /* Ensure ordering of channel info updates */ |
603 | wmb(); | |
604 | ||
605 | qcom_smd_signal_channel(channel); | |
606 | } | |
607 | ||
608 | out: | |
609 | return need_state_scan; | |
610 | } | |
611 | ||
612 | /* | |
613 | * The edge interrupts are triggered by the remote processor on state changes, | |
614 | * channel info updates or when new channels are created. | |
615 | */ | |
616 | static irqreturn_t qcom_smd_edge_intr(int irq, void *data) | |
617 | { | |
618 | struct qcom_smd_edge *edge = data; | |
619 | struct qcom_smd_channel *channel; | |
620 | unsigned available; | |
995b170a BA |
621 | bool kick_scanner = false; |
622 | bool kick_state = false; | |
f2ab3298 BA |
623 | |
624 | /* | |
625 | * Handle state changes or data on each of the channels on this edge | |
626 | */ | |
627 | spin_lock(&edge->channels_lock); | |
628 | list_for_each_entry(channel, &edge->channels, list) { | |
629 | spin_lock(&channel->recv_lock); | |
995b170a | 630 | kick_state |= qcom_smd_channel_intr(channel); |
f2ab3298 BA |
631 | spin_unlock(&channel->recv_lock); |
632 | } | |
633 | spin_unlock(&edge->channels_lock); | |
634 | ||
635 | /* | |
636 | * Creating a new channel requires allocating an smem entry, so we only | |
637 | * have to scan if the amount of available space in smem have changed | |
638 | * since last scan. | |
639 | */ | |
93dbed91 | 640 | available = qcom_smem_get_free_space(edge->remote_pid); |
f2ab3298 BA |
641 | if (available != edge->smem_available) { |
642 | edge->smem_available = available; | |
995b170a | 643 | kick_scanner = true; |
f2ab3298 BA |
644 | } |
645 | ||
995b170a BA |
646 | if (kick_scanner) |
647 | schedule_work(&edge->scan_work); | |
648 | if (kick_state) | |
649 | schedule_work(&edge->state_work); | |
f2ab3298 BA |
650 | |
651 | return IRQ_HANDLED; | |
652 | } | |
653 | ||
654 | /* | |
655 | * Delivers any outstanding packets in the rx fifo, can be used after probe of | |
656 | * the clients to deliver any packets that wasn't delivered before the client | |
657 | * was setup. | |
658 | */ | |
659 | static void qcom_smd_channel_resume(struct qcom_smd_channel *channel) | |
660 | { | |
661 | unsigned long flags; | |
662 | ||
663 | spin_lock_irqsave(&channel->recv_lock, flags); | |
664 | qcom_smd_channel_intr(channel); | |
665 | spin_unlock_irqrestore(&channel->recv_lock, flags); | |
666 | } | |
667 | ||
668 | /* | |
669 | * Calculate how much space is available in the tx fifo. | |
670 | */ | |
671 | static size_t qcom_smd_get_tx_avail(struct qcom_smd_channel *channel) | |
672 | { | |
673 | unsigned head; | |
674 | unsigned tail; | |
675 | unsigned mask = channel->fifo_size - 1; | |
676 | ||
677 | head = GET_TX_CHANNEL_INFO(channel, head); | |
678 | tail = GET_TX_CHANNEL_INFO(channel, tail); | |
679 | ||
680 | return mask - ((head - tail) & mask); | |
681 | } | |
682 | ||
683 | /* | |
684 | * Write count bytes of data into channel, possibly wrapping in the ring buffer | |
685 | */ | |
686 | static int qcom_smd_write_fifo(struct qcom_smd_channel *channel, | |
687 | const void *data, | |
688 | size_t count) | |
689 | { | |
690 | bool word_aligned; | |
691 | unsigned head; | |
692 | size_t len; | |
693 | ||
f02dc825 | 694 | word_aligned = channel->info_word; |
f2ab3298 BA |
695 | head = GET_TX_CHANNEL_INFO(channel, head); |
696 | ||
697 | len = min_t(size_t, count, channel->fifo_size - head); | |
698 | if (len) { | |
699 | smd_copy_to_fifo(channel->tx_fifo + head, | |
700 | data, | |
701 | len, | |
702 | word_aligned); | |
703 | } | |
704 | ||
705 | if (len != count) { | |
706 | smd_copy_to_fifo(channel->tx_fifo, | |
707 | data + len, | |
708 | count - len, | |
709 | word_aligned); | |
710 | } | |
711 | ||
712 | head += count; | |
713 | head &= (channel->fifo_size - 1); | |
714 | SET_TX_CHANNEL_INFO(channel, head, head); | |
715 | ||
716 | return count; | |
717 | } | |
718 | ||
719 | /** | |
720 | * qcom_smd_send - write data to smd channel | |
721 | * @channel: channel handle | |
722 | * @data: buffer of data to write | |
723 | * @len: number of bytes to write | |
724 | * | |
725 | * This is a blocking write of len bytes into the channel's tx ring buffer and | |
726 | * signal the remote end. It will sleep until there is enough space available | |
727 | * in the tx buffer, utilizing the fBLOCKREADINTR signaling mechanism to avoid | |
728 | * polling. | |
729 | */ | |
730 | int qcom_smd_send(struct qcom_smd_channel *channel, const void *data, int len) | |
731 | { | |
24f60e37 | 732 | __le32 hdr[5] = { cpu_to_le32(len), }; |
f2ab3298 BA |
733 | int tlen = sizeof(hdr) + len; |
734 | int ret; | |
735 | ||
736 | /* Word aligned channels only accept word size aligned data */ | |
f02dc825 | 737 | if (channel->info_word && len % 4) |
f2ab3298 BA |
738 | return -EINVAL; |
739 | ||
a208ca98 BA |
740 | /* Reject packets that are too big */ |
741 | if (tlen >= channel->fifo_size) | |
742 | return -EINVAL; | |
743 | ||
f2ab3298 BA |
744 | ret = mutex_lock_interruptible(&channel->tx_lock); |
745 | if (ret) | |
746 | return ret; | |
747 | ||
748 | while (qcom_smd_get_tx_avail(channel) < tlen) { | |
749 | if (channel->state != SMD_CHANNEL_OPENED) { | |
750 | ret = -EPIPE; | |
751 | goto out; | |
752 | } | |
753 | ||
24f60e37 | 754 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 0); |
f2ab3298 BA |
755 | |
756 | ret = wait_event_interruptible(channel->fblockread_event, | |
757 | qcom_smd_get_tx_avail(channel) >= tlen || | |
758 | channel->state != SMD_CHANNEL_OPENED); | |
759 | if (ret) | |
760 | goto out; | |
761 | ||
24f60e37 | 762 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1); |
f2ab3298 BA |
763 | } |
764 | ||
24f60e37 | 765 | SET_TX_CHANNEL_FLAG(channel, fTAIL, 0); |
f2ab3298 BA |
766 | |
767 | qcom_smd_write_fifo(channel, hdr, sizeof(hdr)); | |
768 | qcom_smd_write_fifo(channel, data, len); | |
769 | ||
24f60e37 | 770 | SET_TX_CHANNEL_FLAG(channel, fHEAD, 1); |
f2ab3298 BA |
771 | |
772 | /* Ensure ordering of channel info updates */ | |
773 | wmb(); | |
774 | ||
775 | qcom_smd_signal_channel(channel); | |
776 | ||
777 | out: | |
778 | mutex_unlock(&channel->tx_lock); | |
779 | ||
780 | return ret; | |
781 | } | |
782 | EXPORT_SYMBOL(qcom_smd_send); | |
783 | ||
784 | static struct qcom_smd_device *to_smd_device(struct device *dev) | |
785 | { | |
786 | return container_of(dev, struct qcom_smd_device, dev); | |
787 | } | |
788 | ||
789 | static struct qcom_smd_driver *to_smd_driver(struct device *dev) | |
790 | { | |
791 | struct qcom_smd_device *qsdev = to_smd_device(dev); | |
792 | ||
793 | return container_of(qsdev->dev.driver, struct qcom_smd_driver, driver); | |
794 | } | |
795 | ||
796 | static int qcom_smd_dev_match(struct device *dev, struct device_driver *drv) | |
797 | { | |
1a7caca2 BA |
798 | struct qcom_smd_device *qsdev = to_smd_device(dev); |
799 | struct qcom_smd_driver *qsdrv = container_of(drv, struct qcom_smd_driver, driver); | |
800 | const struct qcom_smd_id *match = qsdrv->smd_match_table; | |
801 | const char *name = qsdev->channel->name; | |
802 | ||
803 | if (match) { | |
804 | while (match->name[0]) { | |
805 | if (!strcmp(match->name, name)) | |
806 | return 1; | |
807 | match++; | |
808 | } | |
809 | } | |
810 | ||
f2ab3298 BA |
811 | return of_driver_match_device(dev, drv); |
812 | } | |
813 | ||
814 | /* | |
3fd3f2fd | 815 | * Helper for opening a channel |
f2ab3298 | 816 | */ |
3fd3f2fd BA |
817 | static int qcom_smd_channel_open(struct qcom_smd_channel *channel, |
818 | qcom_smd_cb_t cb) | |
f2ab3298 | 819 | { |
f2ab3298 | 820 | size_t bb_size; |
f2ab3298 BA |
821 | |
822 | /* | |
823 | * Packets are maximum 4k, but reduce if the fifo is smaller | |
824 | */ | |
825 | bb_size = min(channel->fifo_size, SZ_4K); | |
826 | channel->bounce_buffer = kmalloc(bb_size, GFP_KERNEL); | |
827 | if (!channel->bounce_buffer) | |
828 | return -ENOMEM; | |
829 | ||
3fd3f2fd | 830 | qcom_smd_channel_set_callback(channel, cb); |
f2ab3298 | 831 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING); |
f2ab3298 BA |
832 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED); |
833 | ||
3fd3f2fd BA |
834 | return 0; |
835 | } | |
836 | ||
837 | /* | |
838 | * Helper for closing and resetting a channel | |
839 | */ | |
840 | static void qcom_smd_channel_close(struct qcom_smd_channel *channel) | |
841 | { | |
842 | qcom_smd_channel_set_callback(channel, NULL); | |
843 | ||
844 | kfree(channel->bounce_buffer); | |
845 | channel->bounce_buffer = NULL; | |
846 | ||
847 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED); | |
848 | qcom_smd_channel_reset(channel); | |
849 | } | |
850 | ||
851 | /* | |
852 | * Probe the smd client. | |
853 | * | |
854 | * The remote side have indicated that it want the channel to be opened, so | |
855 | * complete the state handshake and probe our client driver. | |
856 | */ | |
857 | static int qcom_smd_dev_probe(struct device *dev) | |
858 | { | |
859 | struct qcom_smd_device *qsdev = to_smd_device(dev); | |
860 | struct qcom_smd_driver *qsdrv = to_smd_driver(dev); | |
861 | struct qcom_smd_channel *channel = qsdev->channel; | |
862 | int ret; | |
863 | ||
864 | ret = qcom_smd_channel_open(channel, qsdrv->callback); | |
865 | if (ret) | |
866 | return ret; | |
867 | ||
f2ab3298 BA |
868 | ret = qsdrv->probe(qsdev); |
869 | if (ret) | |
870 | goto err; | |
871 | ||
872 | qcom_smd_channel_resume(channel); | |
873 | ||
874 | return 0; | |
875 | ||
876 | err: | |
877 | dev_err(&qsdev->dev, "probe failed\n"); | |
878 | ||
3fd3f2fd | 879 | qcom_smd_channel_close(channel); |
f2ab3298 BA |
880 | return ret; |
881 | } | |
882 | ||
883 | /* | |
884 | * Remove the smd client. | |
885 | * | |
886 | * The channel is going away, for some reason, so remove the smd client and | |
887 | * reset the channel state. | |
888 | */ | |
889 | static int qcom_smd_dev_remove(struct device *dev) | |
890 | { | |
891 | struct qcom_smd_device *qsdev = to_smd_device(dev); | |
892 | struct qcom_smd_driver *qsdrv = to_smd_driver(dev); | |
893 | struct qcom_smd_channel *channel = qsdev->channel; | |
d5933855 BA |
894 | struct qcom_smd_channel *tmp; |
895 | struct qcom_smd_channel *ch; | |
f2ab3298 BA |
896 | |
897 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSING); | |
898 | ||
899 | /* | |
900 | * Make sure we don't race with the code receiving data. | |
901 | */ | |
39f0db29 | 902 | qcom_smd_channel_set_callback(channel, NULL); |
f2ab3298 BA |
903 | |
904 | /* Wake up any sleepers in qcom_smd_send() */ | |
905 | wake_up_interruptible(&channel->fblockread_event); | |
906 | ||
907 | /* | |
908 | * We expect that the client might block in remove() waiting for any | |
909 | * outstanding calls to qcom_smd_send() to wake up and finish. | |
910 | */ | |
911 | if (qsdrv->remove) | |
912 | qsdrv->remove(qsdev); | |
913 | ||
914 | /* | |
d5933855 BA |
915 | * The client is now gone, close and release all channels associated |
916 | * with this sdev | |
f2ab3298 | 917 | */ |
d5933855 BA |
918 | list_for_each_entry_safe(ch, tmp, &channel->dev_list, dev_list) { |
919 | qcom_smd_channel_close(ch); | |
920 | list_del(&ch->dev_list); | |
921 | ch->qsdev = NULL; | |
922 | } | |
f2ab3298 BA |
923 | |
924 | return 0; | |
925 | } | |
926 | ||
927 | static struct bus_type qcom_smd_bus = { | |
928 | .name = "qcom_smd", | |
929 | .match = qcom_smd_dev_match, | |
930 | .probe = qcom_smd_dev_probe, | |
931 | .remove = qcom_smd_dev_remove, | |
932 | }; | |
933 | ||
934 | /* | |
935 | * Release function for the qcom_smd_device object. | |
936 | */ | |
937 | static void qcom_smd_release_device(struct device *dev) | |
938 | { | |
939 | struct qcom_smd_device *qsdev = to_smd_device(dev); | |
940 | ||
941 | kfree(qsdev); | |
942 | } | |
943 | ||
944 | /* | |
945 | * Finds the device_node for the smd child interested in this channel. | |
946 | */ | |
947 | static struct device_node *qcom_smd_match_channel(struct device_node *edge_node, | |
948 | const char *channel) | |
949 | { | |
950 | struct device_node *child; | |
951 | const char *name; | |
952 | const char *key; | |
953 | int ret; | |
954 | ||
955 | for_each_available_child_of_node(edge_node, child) { | |
956 | key = "qcom,smd-channels"; | |
957 | ret = of_property_read_string(child, key, &name); | |
6083096d | 958 | if (ret) |
f2ab3298 | 959 | continue; |
f2ab3298 BA |
960 | |
961 | if (strcmp(name, channel) == 0) | |
962 | return child; | |
963 | } | |
964 | ||
965 | return NULL; | |
966 | } | |
967 | ||
968 | /* | |
969 | * Create a smd client device for channel that is being opened. | |
970 | */ | |
971 | static int qcom_smd_create_device(struct qcom_smd_channel *channel) | |
972 | { | |
973 | struct qcom_smd_device *qsdev; | |
974 | struct qcom_smd_edge *edge = channel->edge; | |
975 | struct device_node *node; | |
976 | struct qcom_smd *smd = edge->smd; | |
977 | int ret; | |
978 | ||
979 | if (channel->qsdev) | |
980 | return -EEXIST; | |
981 | ||
f2ab3298 BA |
982 | dev_dbg(smd->dev, "registering '%s'\n", channel->name); |
983 | ||
984 | qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL); | |
985 | if (!qsdev) | |
986 | return -ENOMEM; | |
987 | ||
1a7caca2 BA |
988 | node = qcom_smd_match_channel(edge->of_node, channel->name); |
989 | dev_set_name(&qsdev->dev, "%s.%s", | |
990 | edge->of_node->name, | |
991 | node ? node->name : channel->name); | |
992 | ||
f2ab3298 BA |
993 | qsdev->dev.parent = smd->dev; |
994 | qsdev->dev.bus = &qcom_smd_bus; | |
995 | qsdev->dev.release = qcom_smd_release_device; | |
996 | qsdev->dev.of_node = node; | |
997 | ||
998 | qsdev->channel = channel; | |
999 | ||
1000 | channel->qsdev = qsdev; | |
1001 | ||
1002 | ret = device_register(&qsdev->dev); | |
1003 | if (ret) { | |
1004 | dev_err(smd->dev, "device_register failed: %d\n", ret); | |
1005 | put_device(&qsdev->dev); | |
1006 | } | |
1007 | ||
1008 | return ret; | |
1009 | } | |
1010 | ||
1011 | /* | |
1012 | * Destroy a smd client device for a channel that's going away. | |
1013 | */ | |
1014 | static void qcom_smd_destroy_device(struct qcom_smd_channel *channel) | |
1015 | { | |
1016 | struct device *dev; | |
1017 | ||
1018 | BUG_ON(!channel->qsdev); | |
1019 | ||
1020 | dev = &channel->qsdev->dev; | |
1021 | ||
1022 | device_unregister(dev); | |
1023 | of_node_put(dev->of_node); | |
1024 | put_device(dev); | |
1025 | } | |
1026 | ||
1027 | /** | |
1028 | * qcom_smd_driver_register - register a smd driver | |
1029 | * @qsdrv: qcom_smd_driver struct | |
1030 | */ | |
1031 | int qcom_smd_driver_register(struct qcom_smd_driver *qsdrv) | |
1032 | { | |
1033 | qsdrv->driver.bus = &qcom_smd_bus; | |
1034 | return driver_register(&qsdrv->driver); | |
1035 | } | |
1036 | EXPORT_SYMBOL(qcom_smd_driver_register); | |
1037 | ||
b853cb96 BA |
1038 | void *qcom_smd_get_drvdata(struct qcom_smd_channel *channel) |
1039 | { | |
1040 | return channel->drvdata; | |
1041 | } | |
1042 | EXPORT_SYMBOL(qcom_smd_get_drvdata); | |
1043 | ||
1044 | void qcom_smd_set_drvdata(struct qcom_smd_channel *channel, void *data) | |
1045 | { | |
1046 | channel->drvdata = data; | |
1047 | } | |
1048 | EXPORT_SYMBOL(qcom_smd_set_drvdata); | |
1049 | ||
f2ab3298 BA |
1050 | /** |
1051 | * qcom_smd_driver_unregister - unregister a smd driver | |
1052 | * @qsdrv: qcom_smd_driver struct | |
1053 | */ | |
1054 | void qcom_smd_driver_unregister(struct qcom_smd_driver *qsdrv) | |
1055 | { | |
1056 | driver_unregister(&qsdrv->driver); | |
1057 | } | |
1058 | EXPORT_SYMBOL(qcom_smd_driver_unregister); | |
1059 | ||
028021d2 BA |
1060 | static struct qcom_smd_channel * |
1061 | qcom_smd_find_channel(struct qcom_smd_edge *edge, const char *name) | |
1062 | { | |
1063 | struct qcom_smd_channel *channel; | |
1064 | struct qcom_smd_channel *ret = NULL; | |
1065 | unsigned long flags; | |
1066 | unsigned state; | |
1067 | ||
1068 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1069 | list_for_each_entry(channel, &edge->channels, list) { | |
1070 | if (strcmp(channel->name, name)) | |
1071 | continue; | |
1072 | ||
1073 | state = GET_RX_CHANNEL_INFO(channel, state); | |
1074 | if (state != SMD_CHANNEL_OPENING && | |
1075 | state != SMD_CHANNEL_OPENED) | |
1076 | continue; | |
1077 | ||
1078 | ret = channel; | |
1079 | break; | |
1080 | } | |
1081 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1082 | ||
1083 | return ret; | |
1084 | } | |
1085 | ||
1086 | /** | |
1087 | * qcom_smd_open_channel() - claim additional channels on the same edge | |
1088 | * @sdev: smd_device handle | |
1089 | * @name: channel name | |
1090 | * @cb: callback method to use for incoming data | |
1091 | * | |
1092 | * Returns a channel handle on success, or -EPROBE_DEFER if the channel isn't | |
1093 | * ready. | |
1094 | */ | |
b853cb96 | 1095 | struct qcom_smd_channel *qcom_smd_open_channel(struct qcom_smd_channel *parent, |
028021d2 BA |
1096 | const char *name, |
1097 | qcom_smd_cb_t cb) | |
1098 | { | |
1099 | struct qcom_smd_channel *channel; | |
b853cb96 BA |
1100 | struct qcom_smd_device *sdev = parent->qsdev; |
1101 | struct qcom_smd_edge *edge = parent->edge; | |
028021d2 BA |
1102 | int ret; |
1103 | ||
1104 | /* Wait up to HZ for the channel to appear */ | |
1105 | ret = wait_event_interruptible_timeout(edge->new_channel_event, | |
1106 | (channel = qcom_smd_find_channel(edge, name)) != NULL, | |
1107 | HZ); | |
1108 | if (!ret) | |
1109 | return ERR_PTR(-ETIMEDOUT); | |
1110 | ||
1111 | if (channel->state != SMD_CHANNEL_CLOSED) { | |
1112 | dev_err(&sdev->dev, "channel %s is busy\n", channel->name); | |
1113 | return ERR_PTR(-EBUSY); | |
1114 | } | |
1115 | ||
1116 | channel->qsdev = sdev; | |
1117 | ret = qcom_smd_channel_open(channel, cb); | |
1118 | if (ret) { | |
1119 | channel->qsdev = NULL; | |
1120 | return ERR_PTR(ret); | |
1121 | } | |
1122 | ||
1123 | /* | |
1124 | * Append the list of channel to the channels associated with the sdev | |
1125 | */ | |
1126 | list_add_tail(&channel->dev_list, &sdev->channel->dev_list); | |
1127 | ||
1128 | return channel; | |
1129 | } | |
1130 | EXPORT_SYMBOL(qcom_smd_open_channel); | |
1131 | ||
f2ab3298 BA |
1132 | /* |
1133 | * Allocate the qcom_smd_channel object for a newly found smd channel, | |
1134 | * retrieving and validating the smem items involved. | |
1135 | */ | |
1136 | static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *edge, | |
1137 | unsigned smem_info_item, | |
1138 | unsigned smem_fifo_item, | |
1139 | char *name) | |
1140 | { | |
1141 | struct qcom_smd_channel *channel; | |
1142 | struct qcom_smd *smd = edge->smd; | |
1143 | size_t fifo_size; | |
1144 | size_t info_size; | |
1145 | void *fifo_base; | |
1146 | void *info; | |
1147 | int ret; | |
1148 | ||
1149 | channel = devm_kzalloc(smd->dev, sizeof(*channel), GFP_KERNEL); | |
1150 | if (!channel) | |
1151 | return ERR_PTR(-ENOMEM); | |
1152 | ||
d5933855 | 1153 | INIT_LIST_HEAD(&channel->dev_list); |
f2ab3298 BA |
1154 | channel->edge = edge; |
1155 | channel->name = devm_kstrdup(smd->dev, name, GFP_KERNEL); | |
1156 | if (!channel->name) | |
1157 | return ERR_PTR(-ENOMEM); | |
1158 | ||
1159 | mutex_init(&channel->tx_lock); | |
1160 | spin_lock_init(&channel->recv_lock); | |
1161 | init_waitqueue_head(&channel->fblockread_event); | |
1162 | ||
1a03964d SB |
1163 | info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size); |
1164 | if (IS_ERR(info)) { | |
1165 | ret = PTR_ERR(info); | |
f2ab3298 | 1166 | goto free_name_and_channel; |
1a03964d | 1167 | } |
f2ab3298 BA |
1168 | |
1169 | /* | |
1170 | * Use the size of the item to figure out which channel info struct to | |
1171 | * use. | |
1172 | */ | |
1173 | if (info_size == 2 * sizeof(struct smd_channel_info_word)) { | |
f02dc825 | 1174 | channel->info_word = info; |
f2ab3298 | 1175 | } else if (info_size == 2 * sizeof(struct smd_channel_info)) { |
f02dc825 | 1176 | channel->info = info; |
f2ab3298 BA |
1177 | } else { |
1178 | dev_err(smd->dev, | |
1179 | "channel info of size %zu not supported\n", info_size); | |
1180 | ret = -EINVAL; | |
1181 | goto free_name_and_channel; | |
1182 | } | |
1183 | ||
1a03964d SB |
1184 | fifo_base = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_size); |
1185 | if (IS_ERR(fifo_base)) { | |
1186 | ret = PTR_ERR(fifo_base); | |
f2ab3298 | 1187 | goto free_name_and_channel; |
1a03964d | 1188 | } |
f2ab3298 BA |
1189 | |
1190 | /* The channel consist of a rx and tx fifo of equal size */ | |
1191 | fifo_size /= 2; | |
1192 | ||
1193 | dev_dbg(smd->dev, "new channel '%s' info-size: %zu fifo-size: %zu\n", | |
1194 | name, info_size, fifo_size); | |
1195 | ||
1196 | channel->tx_fifo = fifo_base; | |
1197 | channel->rx_fifo = fifo_base + fifo_size; | |
1198 | channel->fifo_size = fifo_size; | |
1199 | ||
1200 | qcom_smd_channel_reset(channel); | |
1201 | ||
1202 | return channel; | |
1203 | ||
1204 | free_name_and_channel: | |
1205 | devm_kfree(smd->dev, channel->name); | |
1206 | devm_kfree(smd->dev, channel); | |
1207 | ||
1208 | return ERR_PTR(ret); | |
1209 | } | |
1210 | ||
1211 | /* | |
1212 | * Scans the allocation table for any newly allocated channels, calls | |
1213 | * qcom_smd_create_channel() to create representations of these and add | |
1214 | * them to the edge's list of channels. | |
1215 | */ | |
995b170a | 1216 | static void qcom_channel_scan_worker(struct work_struct *work) |
f2ab3298 | 1217 | { |
995b170a | 1218 | struct qcom_smd_edge *edge = container_of(work, struct qcom_smd_edge, scan_work); |
f2ab3298 BA |
1219 | struct qcom_smd_alloc_entry *alloc_tbl; |
1220 | struct qcom_smd_alloc_entry *entry; | |
1221 | struct qcom_smd_channel *channel; | |
1222 | struct qcom_smd *smd = edge->smd; | |
1223 | unsigned long flags; | |
1224 | unsigned fifo_id; | |
1225 | unsigned info_id; | |
f2ab3298 BA |
1226 | int tbl; |
1227 | int i; | |
24f60e37 | 1228 | u32 eflags, cid; |
f2ab3298 BA |
1229 | |
1230 | for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) { | |
1a03964d SB |
1231 | alloc_tbl = qcom_smem_get(edge->remote_pid, |
1232 | smem_items[tbl].alloc_tbl_id, NULL); | |
1233 | if (IS_ERR(alloc_tbl)) | |
f2ab3298 BA |
1234 | continue; |
1235 | ||
1236 | for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) { | |
1237 | entry = &alloc_tbl[i]; | |
24f60e37 | 1238 | eflags = le32_to_cpu(entry->flags); |
f2ab3298 BA |
1239 | if (test_bit(i, edge->allocated[tbl])) |
1240 | continue; | |
1241 | ||
1242 | if (entry->ref_count == 0) | |
1243 | continue; | |
1244 | ||
1245 | if (!entry->name[0]) | |
1246 | continue; | |
1247 | ||
24f60e37 | 1248 | if (!(eflags & SMD_CHANNEL_FLAGS_PACKET)) |
f2ab3298 BA |
1249 | continue; |
1250 | ||
24f60e37 | 1251 | if ((eflags & SMD_CHANNEL_FLAGS_EDGE_MASK) != edge->edge_id) |
f2ab3298 BA |
1252 | continue; |
1253 | ||
24f60e37 SB |
1254 | cid = le32_to_cpu(entry->cid); |
1255 | info_id = smem_items[tbl].info_base_id + cid; | |
1256 | fifo_id = smem_items[tbl].fifo_base_id + cid; | |
f2ab3298 BA |
1257 | |
1258 | channel = qcom_smd_create_channel(edge, info_id, fifo_id, entry->name); | |
1259 | if (IS_ERR(channel)) | |
1260 | continue; | |
1261 | ||
1262 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1263 | list_add(&channel->list, &edge->channels); | |
1264 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1265 | ||
1266 | dev_dbg(smd->dev, "new channel found: '%s'\n", channel->name); | |
1267 | set_bit(i, edge->allocated[tbl]); | |
028021d2 BA |
1268 | |
1269 | wake_up_interruptible(&edge->new_channel_event); | |
f2ab3298 BA |
1270 | } |
1271 | } | |
1272 | ||
995b170a | 1273 | schedule_work(&edge->state_work); |
f2ab3298 BA |
1274 | } |
1275 | ||
1276 | /* | |
1277 | * This per edge worker scans smem for any new channels and register these. It | |
1278 | * then scans all registered channels for state changes that should be handled | |
1279 | * by creating or destroying smd client devices for the registered channels. | |
1280 | * | |
995b170a BA |
1281 | * LOCKING: edge->channels_lock only needs to cover the list operations, as the |
1282 | * worker is killed before any channels are deallocated | |
f2ab3298 BA |
1283 | */ |
1284 | static void qcom_channel_state_worker(struct work_struct *work) | |
1285 | { | |
1286 | struct qcom_smd_channel *channel; | |
1287 | struct qcom_smd_edge *edge = container_of(work, | |
1288 | struct qcom_smd_edge, | |
995b170a | 1289 | state_work); |
f2ab3298 | 1290 | unsigned remote_state; |
995b170a | 1291 | unsigned long flags; |
f2ab3298 BA |
1292 | |
1293 | /* | |
1294 | * Register a device for any closed channel where the remote processor | |
1295 | * is showing interest in opening the channel. | |
1296 | */ | |
995b170a | 1297 | spin_lock_irqsave(&edge->channels_lock, flags); |
f2ab3298 BA |
1298 | list_for_each_entry(channel, &edge->channels, list) { |
1299 | if (channel->state != SMD_CHANNEL_CLOSED) | |
1300 | continue; | |
1301 | ||
1302 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
1303 | if (remote_state != SMD_CHANNEL_OPENING && | |
1304 | remote_state != SMD_CHANNEL_OPENED) | |
1305 | continue; | |
1306 | ||
995b170a | 1307 | spin_unlock_irqrestore(&edge->channels_lock, flags); |
f2ab3298 | 1308 | qcom_smd_create_device(channel); |
995b170a | 1309 | spin_lock_irqsave(&edge->channels_lock, flags); |
f2ab3298 BA |
1310 | } |
1311 | ||
1312 | /* | |
1313 | * Unregister the device for any channel that is opened where the | |
1314 | * remote processor is closing the channel. | |
1315 | */ | |
1316 | list_for_each_entry(channel, &edge->channels, list) { | |
1317 | if (channel->state != SMD_CHANNEL_OPENING && | |
1318 | channel->state != SMD_CHANNEL_OPENED) | |
1319 | continue; | |
1320 | ||
1321 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
1322 | if (remote_state == SMD_CHANNEL_OPENING || | |
1323 | remote_state == SMD_CHANNEL_OPENED) | |
1324 | continue; | |
1325 | ||
995b170a | 1326 | spin_unlock_irqrestore(&edge->channels_lock, flags); |
f2ab3298 | 1327 | qcom_smd_destroy_device(channel); |
995b170a | 1328 | spin_lock_irqsave(&edge->channels_lock, flags); |
f2ab3298 | 1329 | } |
995b170a | 1330 | spin_unlock_irqrestore(&edge->channels_lock, flags); |
f2ab3298 BA |
1331 | } |
1332 | ||
1333 | /* | |
1334 | * Parses an of_node describing an edge. | |
1335 | */ | |
1336 | static int qcom_smd_parse_edge(struct device *dev, | |
1337 | struct device_node *node, | |
1338 | struct qcom_smd_edge *edge) | |
1339 | { | |
1340 | struct device_node *syscon_np; | |
1341 | const char *key; | |
1342 | int irq; | |
1343 | int ret; | |
1344 | ||
1345 | INIT_LIST_HEAD(&edge->channels); | |
1346 | spin_lock_init(&edge->channels_lock); | |
1347 | ||
995b170a BA |
1348 | INIT_WORK(&edge->scan_work, qcom_channel_scan_worker); |
1349 | INIT_WORK(&edge->state_work, qcom_channel_state_worker); | |
f2ab3298 BA |
1350 | |
1351 | edge->of_node = of_node_get(node); | |
1352 | ||
1353 | irq = irq_of_parse_and_map(node, 0); | |
1354 | if (irq < 0) { | |
1355 | dev_err(dev, "required smd interrupt missing\n"); | |
1356 | return -EINVAL; | |
1357 | } | |
1358 | ||
1359 | ret = devm_request_irq(dev, irq, | |
1360 | qcom_smd_edge_intr, IRQF_TRIGGER_RISING, | |
1361 | node->name, edge); | |
1362 | if (ret) { | |
1363 | dev_err(dev, "failed to request smd irq\n"); | |
1364 | return ret; | |
1365 | } | |
1366 | ||
1367 | edge->irq = irq; | |
1368 | ||
1369 | key = "qcom,smd-edge"; | |
1370 | ret = of_property_read_u32(node, key, &edge->edge_id); | |
1371 | if (ret) { | |
1372 | dev_err(dev, "edge missing %s property\n", key); | |
1373 | return -EINVAL; | |
1374 | } | |
1375 | ||
93dbed91 AG |
1376 | edge->remote_pid = QCOM_SMEM_HOST_ANY; |
1377 | key = "qcom,remote-pid"; | |
1378 | of_property_read_u32(node, key, &edge->remote_pid); | |
1379 | ||
f2ab3298 BA |
1380 | syscon_np = of_parse_phandle(node, "qcom,ipc", 0); |
1381 | if (!syscon_np) { | |
1382 | dev_err(dev, "no qcom,ipc node\n"); | |
1383 | return -ENODEV; | |
1384 | } | |
1385 | ||
1386 | edge->ipc_regmap = syscon_node_to_regmap(syscon_np); | |
1387 | if (IS_ERR(edge->ipc_regmap)) | |
1388 | return PTR_ERR(edge->ipc_regmap); | |
1389 | ||
1390 | key = "qcom,ipc"; | |
1391 | ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset); | |
1392 | if (ret < 0) { | |
1393 | dev_err(dev, "no offset in %s\n", key); | |
1394 | return -EINVAL; | |
1395 | } | |
1396 | ||
1397 | ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit); | |
1398 | if (ret < 0) { | |
1399 | dev_err(dev, "no bit in %s\n", key); | |
1400 | return -EINVAL; | |
1401 | } | |
1402 | ||
1403 | return 0; | |
1404 | } | |
1405 | ||
1406 | static int qcom_smd_probe(struct platform_device *pdev) | |
1407 | { | |
1408 | struct qcom_smd_edge *edge; | |
1409 | struct device_node *node; | |
1410 | struct qcom_smd *smd; | |
1411 | size_t array_size; | |
1412 | int num_edges; | |
1413 | int ret; | |
1414 | int i = 0; | |
1a03964d | 1415 | void *p; |
f2ab3298 BA |
1416 | |
1417 | /* Wait for smem */ | |
1a03964d SB |
1418 | p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL); |
1419 | if (PTR_ERR(p) == -EPROBE_DEFER) | |
1420 | return PTR_ERR(p); | |
f2ab3298 BA |
1421 | |
1422 | num_edges = of_get_available_child_count(pdev->dev.of_node); | |
1423 | array_size = sizeof(*smd) + num_edges * sizeof(struct qcom_smd_edge); | |
1424 | smd = devm_kzalloc(&pdev->dev, array_size, GFP_KERNEL); | |
1425 | if (!smd) | |
1426 | return -ENOMEM; | |
1427 | smd->dev = &pdev->dev; | |
1428 | ||
1429 | smd->num_edges = num_edges; | |
1430 | for_each_available_child_of_node(pdev->dev.of_node, node) { | |
1431 | edge = &smd->edges[i++]; | |
1432 | edge->smd = smd; | |
028021d2 | 1433 | init_waitqueue_head(&edge->new_channel_event); |
f2ab3298 BA |
1434 | |
1435 | ret = qcom_smd_parse_edge(&pdev->dev, node, edge); | |
1436 | if (ret) | |
1437 | continue; | |
1438 | ||
995b170a | 1439 | schedule_work(&edge->scan_work); |
f2ab3298 BA |
1440 | } |
1441 | ||
1442 | platform_set_drvdata(pdev, smd); | |
1443 | ||
1444 | return 0; | |
1445 | } | |
1446 | ||
1447 | /* | |
1448 | * Shut down all smd clients by making sure that each edge stops processing | |
1449 | * events and scanning for new channels, then call destroy on the devices. | |
1450 | */ | |
1451 | static int qcom_smd_remove(struct platform_device *pdev) | |
1452 | { | |
1453 | struct qcom_smd_channel *channel; | |
1454 | struct qcom_smd_edge *edge; | |
1455 | struct qcom_smd *smd = platform_get_drvdata(pdev); | |
1456 | int i; | |
1457 | ||
1458 | for (i = 0; i < smd->num_edges; i++) { | |
1459 | edge = &smd->edges[i]; | |
1460 | ||
1461 | disable_irq(edge->irq); | |
995b170a BA |
1462 | cancel_work_sync(&edge->scan_work); |
1463 | cancel_work_sync(&edge->state_work); | |
f2ab3298 | 1464 | |
995b170a | 1465 | /* No need to lock here, because the writer is gone */ |
f2ab3298 BA |
1466 | list_for_each_entry(channel, &edge->channels, list) { |
1467 | if (!channel->qsdev) | |
1468 | continue; | |
1469 | ||
1470 | qcom_smd_destroy_device(channel); | |
1471 | } | |
1472 | } | |
1473 | ||
1474 | return 0; | |
1475 | } | |
1476 | ||
1477 | static const struct of_device_id qcom_smd_of_match[] = { | |
1478 | { .compatible = "qcom,smd" }, | |
1479 | {} | |
1480 | }; | |
1481 | MODULE_DEVICE_TABLE(of, qcom_smd_of_match); | |
1482 | ||
1483 | static struct platform_driver qcom_smd_driver = { | |
1484 | .probe = qcom_smd_probe, | |
1485 | .remove = qcom_smd_remove, | |
1486 | .driver = { | |
1487 | .name = "qcom-smd", | |
1488 | .of_match_table = qcom_smd_of_match, | |
1489 | }, | |
1490 | }; | |
1491 | ||
1492 | static int __init qcom_smd_init(void) | |
1493 | { | |
1494 | int ret; | |
1495 | ||
1496 | ret = bus_register(&qcom_smd_bus); | |
1497 | if (ret) { | |
1498 | pr_err("failed to register smd bus: %d\n", ret); | |
1499 | return ret; | |
1500 | } | |
1501 | ||
1502 | return platform_driver_register(&qcom_smd_driver); | |
1503 | } | |
1504 | postcore_initcall(qcom_smd_init); | |
1505 | ||
1506 | static void __exit qcom_smd_exit(void) | |
1507 | { | |
1508 | platform_driver_unregister(&qcom_smd_driver); | |
1509 | bus_unregister(&qcom_smd_bus); | |
1510 | } | |
1511 | module_exit(qcom_smd_exit); | |
1512 | ||
1513 | MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); | |
1514 | MODULE_DESCRIPTION("Qualcomm Shared Memory Driver"); | |
1515 | MODULE_LICENSE("GPL v2"); |