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