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do not shrink nbcongwin below mss
[cor.git] / sound / xen / xen_snd_front_alsa.c
blobe01631959ed8930e5051f8ea91c752488d851ff1
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2
3 /*
4 * Xen para-virtual sound device
5 *
6 * Copyright (C) 2016-2018 EPAM Systems Inc.
7 *
8 * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
9 */
10
11 #include <linux/platform_device.h>
12
13 #include <sound/core.h>
14 #include <sound/pcm.h>
15 #include <sound/pcm_params.h>
16
17 #include <xen/xenbus.h>
18 #include <xen/xen-front-pgdir-shbuf.h>
19
20 #include "xen_snd_front.h"
21 #include "xen_snd_front_alsa.h"
22 #include "xen_snd_front_cfg.h"
23 #include "xen_snd_front_evtchnl.h"
24
25 struct xen_snd_front_pcm_stream_info {
26 struct xen_snd_front_info *front_info;
27 struct xen_snd_front_evtchnl_pair *evt_pair;
28
29 /* This is the shared buffer with its backing storage. */
30 struct xen_front_pgdir_shbuf shbuf;
31 u8 *buffer;
32 size_t buffer_sz;
33 int num_pages;
34 struct page **pages;
35
36 int index;
37
38 bool is_open;
39 struct snd_pcm_hardware pcm_hw;
40
41 /* Number of processed frames as reported by the backend. */
42 snd_pcm_uframes_t be_cur_frame;
43 /* Current HW pointer to be reported via .period callback. */
44 atomic_t hw_ptr;
45 /* Modulo of the number of processed frames - for period detection. */
46 u32 out_frames;
47 };
48
49 struct xen_snd_front_pcm_instance_info {
50 struct xen_snd_front_card_info *card_info;
51 struct snd_pcm *pcm;
52 struct snd_pcm_hardware pcm_hw;
53 int num_pcm_streams_pb;
54 struct xen_snd_front_pcm_stream_info *streams_pb;
55 int num_pcm_streams_cap;
56 struct xen_snd_front_pcm_stream_info *streams_cap;
57 };
58
59 struct xen_snd_front_card_info {
60 struct xen_snd_front_info *front_info;
61 struct snd_card *card;
62 struct snd_pcm_hardware pcm_hw;
63 int num_pcm_instances;
64 struct xen_snd_front_pcm_instance_info *pcm_instances;
65 };
66
67 struct alsa_sndif_sample_format {
68 u8 sndif;
69 snd_pcm_format_t alsa;
70 };
71
72 struct alsa_sndif_hw_param {
73 u8 sndif;
74 snd_pcm_hw_param_t alsa;
75 };
76
77 static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
78 {
79 .sndif = XENSND_PCM_FORMAT_U8,
80 .alsa = SNDRV_PCM_FORMAT_U8
81 },
82 {
83 .sndif = XENSND_PCM_FORMAT_S8,
84 .alsa = SNDRV_PCM_FORMAT_S8
85 },
86 {
87 .sndif = XENSND_PCM_FORMAT_U16_LE,
88 .alsa = SNDRV_PCM_FORMAT_U16_LE
89 },
90 {
91 .sndif = XENSND_PCM_FORMAT_U16_BE,
92 .alsa = SNDRV_PCM_FORMAT_U16_BE
93 },
94 {
95 .sndif = XENSND_PCM_FORMAT_S16_LE,
96 .alsa = SNDRV_PCM_FORMAT_S16_LE
97 },
98 {
99 .sndif = XENSND_PCM_FORMAT_S16_BE,
100 .alsa = SNDRV_PCM_FORMAT_S16_BE
101 },
102 {
103 .sndif = XENSND_PCM_FORMAT_U24_LE,
104 .alsa = SNDRV_PCM_FORMAT_U24_LE
105 },
106 {
107 .sndif = XENSND_PCM_FORMAT_U24_BE,
108 .alsa = SNDRV_PCM_FORMAT_U24_BE
109 },
110 {
111 .sndif = XENSND_PCM_FORMAT_S24_LE,
112 .alsa = SNDRV_PCM_FORMAT_S24_LE
113 },
114 {
115 .sndif = XENSND_PCM_FORMAT_S24_BE,
116 .alsa = SNDRV_PCM_FORMAT_S24_BE
117 },
118 {
119 .sndif = XENSND_PCM_FORMAT_U32_LE,
120 .alsa = SNDRV_PCM_FORMAT_U32_LE
121 },
122 {
123 .sndif = XENSND_PCM_FORMAT_U32_BE,
124 .alsa = SNDRV_PCM_FORMAT_U32_BE
125 },
126 {
127 .sndif = XENSND_PCM_FORMAT_S32_LE,
128 .alsa = SNDRV_PCM_FORMAT_S32_LE
129 },
130 {
131 .sndif = XENSND_PCM_FORMAT_S32_BE,
132 .alsa = SNDRV_PCM_FORMAT_S32_BE
133 },
134 {
135 .sndif = XENSND_PCM_FORMAT_A_LAW,
136 .alsa = SNDRV_PCM_FORMAT_A_LAW
137 },
138 {
139 .sndif = XENSND_PCM_FORMAT_MU_LAW,
140 .alsa = SNDRV_PCM_FORMAT_MU_LAW
141 },
142 {
143 .sndif = XENSND_PCM_FORMAT_F32_LE,
144 .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
145 },
146 {
147 .sndif = XENSND_PCM_FORMAT_F32_BE,
148 .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
149 },
150 {
151 .sndif = XENSND_PCM_FORMAT_F64_LE,
152 .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
153 },
154 {
155 .sndif = XENSND_PCM_FORMAT_F64_BE,
156 .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
157 },
158 {
159 .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
160 .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
161 },
162 {
163 .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
164 .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
165 },
166 {
167 .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
168 .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
169 },
170 {
171 .sndif = XENSND_PCM_FORMAT_MPEG,
172 .alsa = SNDRV_PCM_FORMAT_MPEG
173 },
174 {
175 .sndif = XENSND_PCM_FORMAT_GSM,
176 .alsa = SNDRV_PCM_FORMAT_GSM
177 },
178 };
179
180 static int to_sndif_format(snd_pcm_format_t format)
181 {
182 int i;
183
184 for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
185 if (ALSA_SNDIF_FORMATS[i].alsa == format)
186 return ALSA_SNDIF_FORMATS[i].sndif;
187
188 return -EINVAL;
189 }
190
191 static u64 to_sndif_formats_mask(u64 alsa_formats)
192 {
193 u64 mask;
194 int i;
195
196 mask = 0;
197 for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
198 if (pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa) & alsa_formats)
199 mask |= BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif);
200
201 return mask;
202 }
203
204 static u64 to_alsa_formats_mask(u64 sndif_formats)
205 {
206 u64 mask;
207 int i;
208
209 mask = 0;
210 for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
211 if (BIT_ULL(ALSA_SNDIF_FORMATS[i].sndif) & sndif_formats)
212 mask |= pcm_format_to_bits(ALSA_SNDIF_FORMATS[i].alsa);
213
214 return mask;
215 }
216
217 static void stream_clear(struct xen_snd_front_pcm_stream_info *stream)
218 {
219 stream->is_open = false;
220 stream->be_cur_frame = 0;
221 stream->out_frames = 0;
222 atomic_set(&stream->hw_ptr, 0);
223 xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
224 memset(&stream->shbuf, 0, sizeof(stream->shbuf));
225 stream->buffer = NULL;
226 stream->buffer_sz = 0;
227 stream->pages = NULL;
228 stream->num_pages = 0;
229 }
230
231 static void stream_free(struct xen_snd_front_pcm_stream_info *stream)
232 {
233 xen_front_pgdir_shbuf_unmap(&stream->shbuf);
234 xen_front_pgdir_shbuf_free(&stream->shbuf);
235 if (stream->buffer)
236 free_pages_exact(stream->buffer, stream->buffer_sz);
237 kfree(stream->pages);
238 stream_clear(stream);
239 }
240
241 static struct xen_snd_front_pcm_stream_info *
242 stream_get(struct snd_pcm_substream *substream)
243 {
244 struct xen_snd_front_pcm_instance_info *pcm_instance =
245 snd_pcm_substream_chip(substream);
246 struct xen_snd_front_pcm_stream_info *stream;
247
248 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
249 stream = &pcm_instance->streams_pb[substream->number];
250 else
251 stream = &pcm_instance->streams_cap[substream->number];
252
253 return stream;
254 }
255
256 static int alsa_hw_rule(struct snd_pcm_hw_params *params,
257 struct snd_pcm_hw_rule *rule)
258 {
259 struct xen_snd_front_pcm_stream_info *stream = rule->private;
260 struct device *dev = &stream->front_info->xb_dev->dev;
261 struct snd_mask *formats =
262 hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
263 struct snd_interval *rates =
264 hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
265 struct snd_interval *channels =
266 hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
267 struct snd_interval *period =
268 hw_param_interval(params,
269 SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
270 struct snd_interval *buffer =
271 hw_param_interval(params,
272 SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
273 struct xensnd_query_hw_param req;
274 struct xensnd_query_hw_param resp;
275 struct snd_interval interval;
276 struct snd_mask mask;
277 u64 sndif_formats;
278 int changed, ret;
279
280 /* Collect all the values we need for the query. */
281
282 req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
283 (u64)(formats->bits[1]) << 32);
284
285 req.rates.min = rates->min;
286 req.rates.max = rates->max;
287
288 req.channels.min = channels->min;
289 req.channels.max = channels->max;
290
291 req.buffer.min = buffer->min;
292 req.buffer.max = buffer->max;
293
294 req.period.min = period->min;
295 req.period.max = period->max;
296
297 ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
298 &req, &resp);
299 if (ret < 0) {
300 /* Check if this is due to backend communication error. */
301 if (ret == -EIO || ret == -ETIMEDOUT)
302 dev_err(dev, "Failed to query ALSA HW parameters\n");
303 return ret;
304 }
305
306 /* Refine HW parameters after the query. */
307 changed = 0;
308
309 sndif_formats = to_alsa_formats_mask(resp.formats);
310 snd_mask_none(&mask);
311 mask.bits[0] = (u32)sndif_formats;
312 mask.bits[1] = (u32)(sndif_formats >> 32);
313 ret = snd_mask_refine(formats, &mask);
314 if (ret < 0)
315 return ret;
316 changed |= ret;
317
318 interval.openmin = 0;
319 interval.openmax = 0;
320 interval.integer = 1;
321
322 interval.min = resp.rates.min;
323 interval.max = resp.rates.max;
324 ret = snd_interval_refine(rates, &interval);
325 if (ret < 0)
326 return ret;
327 changed |= ret;
328
329 interval.min = resp.channels.min;
330 interval.max = resp.channels.max;
331 ret = snd_interval_refine(channels, &interval);
332 if (ret < 0)
333 return ret;
334 changed |= ret;
335
336 interval.min = resp.buffer.min;
337 interval.max = resp.buffer.max;
338 ret = snd_interval_refine(buffer, &interval);
339 if (ret < 0)
340 return ret;
341 changed |= ret;
342
343 interval.min = resp.period.min;
344 interval.max = resp.period.max;
345 ret = snd_interval_refine(period, &interval);
346 if (ret < 0)
347 return ret;
348 changed |= ret;
349
350 return changed;
351 }
352
353 static int alsa_open(struct snd_pcm_substream *substream)
354 {
355 struct xen_snd_front_pcm_instance_info *pcm_instance =
356 snd_pcm_substream_chip(substream);
357 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
358 struct snd_pcm_runtime *runtime = substream->runtime;
359 struct xen_snd_front_info *front_info =
360 pcm_instance->card_info->front_info;
361 struct device *dev = &front_info->xb_dev->dev;
362 int ret;
363
364 /*
365 * Return our HW properties: override defaults with those configured
366 * via XenStore.
367 */
368 runtime->hw = stream->pcm_hw;
369 runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
370 SNDRV_PCM_INFO_MMAP_VALID |
371 SNDRV_PCM_INFO_DOUBLE |
372 SNDRV_PCM_INFO_BATCH |
373 SNDRV_PCM_INFO_NONINTERLEAVED |
374 SNDRV_PCM_INFO_RESUME |
375 SNDRV_PCM_INFO_PAUSE);
376 runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
377
378 stream->evt_pair = &front_info->evt_pairs[stream->index];
379
380 stream->front_info = front_info;
381
382 stream->evt_pair->evt.u.evt.substream = substream;
383
384 stream_clear(stream);
385
386 xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
387
388 ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
389 alsa_hw_rule, stream,
390 SNDRV_PCM_HW_PARAM_FORMAT, -1);
391 if (ret) {
392 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");
393 return ret;
394 }
395
396 ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
397 alsa_hw_rule, stream,
398 SNDRV_PCM_HW_PARAM_RATE, -1);
399 if (ret) {
400 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");
401 return ret;
402 }
403
404 ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
405 alsa_hw_rule, stream,
406 SNDRV_PCM_HW_PARAM_CHANNELS, -1);
407 if (ret) {
408 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");
409 return ret;
410 }
411
412 ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
413 alsa_hw_rule, stream,
414 SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
415 if (ret) {
416 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
417 return ret;
418 }
419
420 ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
421 alsa_hw_rule, stream,
422 SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
423 if (ret) {
424 dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
425 return ret;
426 }
427
428 return 0;
429 }
430
431 static int alsa_close(struct snd_pcm_substream *substream)
432 {
433 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
434
435 xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
436 return 0;
437 }
438
439 static int shbuf_setup_backstore(struct xen_snd_front_pcm_stream_info *stream,
440 size_t buffer_sz)
441 {
442 int i;
443
444 stream->buffer = alloc_pages_exact(buffer_sz, GFP_KERNEL);
445 if (!stream->buffer)
446 return -ENOMEM;
447
448 stream->buffer_sz = buffer_sz;
449 stream->num_pages = DIV_ROUND_UP(stream->buffer_sz, PAGE_SIZE);
450 stream->pages = kcalloc(stream->num_pages, sizeof(struct page *),
451 GFP_KERNEL);
452 if (!stream->pages)
453 return -ENOMEM;
454
455 for (i = 0; i < stream->num_pages; i++)
456 stream->pages[i] = virt_to_page(stream->buffer + i * PAGE_SIZE);
457
458 return 0;
459 }
460
461 static int alsa_hw_params(struct snd_pcm_substream *substream,
462 struct snd_pcm_hw_params *params)
463 {
464 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
465 struct xen_snd_front_info *front_info = stream->front_info;
466 struct xen_front_pgdir_shbuf_cfg buf_cfg;
467 int ret;
468
469 /*
470 * This callback may be called multiple times,
471 * so free the previously allocated shared buffer if any.
472 */
473 stream_free(stream);
474 ret = shbuf_setup_backstore(stream, params_buffer_bytes(params));
475 if (ret < 0)
476 goto fail;
477
478 memset(&buf_cfg, 0, sizeof(buf_cfg));
479 buf_cfg.xb_dev = front_info->xb_dev;
480 buf_cfg.pgdir = &stream->shbuf;
481 buf_cfg.num_pages = stream->num_pages;
482 buf_cfg.pages = stream->pages;
483
484 ret = xen_front_pgdir_shbuf_alloc(&buf_cfg);
485 if (ret < 0)
486 goto fail;
487
488 ret = xen_front_pgdir_shbuf_map(&stream->shbuf);
489 if (ret < 0)
490 goto fail;
491
492 return 0;
493
494 fail:
495 stream_free(stream);
496 dev_err(&front_info->xb_dev->dev,
497 "Failed to allocate buffers for stream with index %d\n",
498 stream->index);
499 return ret;
500 }
501
502 static int alsa_hw_free(struct snd_pcm_substream *substream)
503 {
504 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
505 int ret;
506
507 ret = xen_snd_front_stream_close(&stream->evt_pair->req);
508 stream_free(stream);
509 return ret;
510 }
511
512 static int alsa_prepare(struct snd_pcm_substream *substream)
513 {
514 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
515
516 if (!stream->is_open) {
517 struct snd_pcm_runtime *runtime = substream->runtime;
518 u8 sndif_format;
519 int ret;
520
521 ret = to_sndif_format(runtime->format);
522 if (ret < 0) {
523 dev_err(&stream->front_info->xb_dev->dev,
524 "Unsupported sample format: %d\n",
525 runtime->format);
526 return ret;
527 }
528 sndif_format = ret;
529
530 ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
531 &stream->shbuf,
532 sndif_format,
533 runtime->channels,
534 runtime->rate,
535 snd_pcm_lib_buffer_bytes(substream),
536 snd_pcm_lib_period_bytes(substream));
537 if (ret < 0)
538 return ret;
539
540 stream->is_open = true;
541 }
542
543 return 0;
544 }
545
546 static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
547 {
548 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
549 int type;
550
551 switch (cmd) {
552 case SNDRV_PCM_TRIGGER_START:
553 type = XENSND_OP_TRIGGER_START;
554 break;
555
556 case SNDRV_PCM_TRIGGER_RESUME:
557 type = XENSND_OP_TRIGGER_RESUME;
558 break;
559
560 case SNDRV_PCM_TRIGGER_STOP:
561 type = XENSND_OP_TRIGGER_STOP;
562 break;
563
564 case SNDRV_PCM_TRIGGER_SUSPEND:
565 type = XENSND_OP_TRIGGER_PAUSE;
566 break;
567
568 default:
569 return -EINVAL;
570 }
571
572 return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
573 }
574
575 void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
576 u64 pos_bytes)
577 {
578 struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
579 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
580 snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
581
582 cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
583
584 delta = cur_frame - stream->be_cur_frame;
585 stream->be_cur_frame = cur_frame;
586
587 new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
588 new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;
589 atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
590
591 stream->out_frames += delta;
592 if (stream->out_frames > substream->runtime->period_size) {
593 stream->out_frames %= substream->runtime->period_size;
594 snd_pcm_period_elapsed(substream);
595 }
596 }
597
598 static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)
599 {
600 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
601
602 return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
603 }
604
605 static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
606 int channel, unsigned long pos, void __user *src,
607 unsigned long count)
608 {
609 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
610
611 if (unlikely(pos + count > stream->buffer_sz))
612 return -EINVAL;
613
614 if (copy_from_user(stream->buffer + pos, src, count))
615 return -EFAULT;
616
617 return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
618 }
619
620 static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
621 int channel, unsigned long pos, void *src,
622 unsigned long count)
623 {
624 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
625
626 if (unlikely(pos + count > stream->buffer_sz))
627 return -EINVAL;
628
629 memcpy(stream->buffer + pos, src, count);
630
631 return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
632 }
633
634 static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
635 int channel, unsigned long pos, void __user *dst,
636 unsigned long count)
637 {
638 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
639 int ret;
640
641 if (unlikely(pos + count > stream->buffer_sz))
642 return -EINVAL;
643
644 ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
645 if (ret < 0)
646 return ret;
647
648 return copy_to_user(dst, stream->buffer + pos, count) ?
649 -EFAULT : 0;
650 }
651
652 static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
653 int channel, unsigned long pos, void *dst,
654 unsigned long count)
655 {
656 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
657 int ret;
658
659 if (unlikely(pos + count > stream->buffer_sz))
660 return -EINVAL;
661
662 ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
663 if (ret < 0)
664 return ret;
665
666 memcpy(dst, stream->buffer + pos, count);
667
668 return 0;
669 }
670
671 static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
672 int channel, unsigned long pos,
673 unsigned long count)
674 {
675 struct xen_snd_front_pcm_stream_info *stream = stream_get(substream);
676
677 if (unlikely(pos + count > stream->buffer_sz))
678 return -EINVAL;
679
680 memset(stream->buffer + pos, 0, count);
681
682 return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
683 }
684
685 /*
686 * FIXME: The mmaped data transfer is asynchronous and there is no
687 * ack signal from user-space when it is done. This is the
688 * reason it is not implemented in the PV driver as we do need
689 * to know when the buffer can be transferred to the backend.
690 */
691
692 static const struct snd_pcm_ops snd_drv_alsa_playback_ops = {
693 .open = alsa_open,
694 .close = alsa_close,
695 .ioctl = snd_pcm_lib_ioctl,
696 .hw_params = alsa_hw_params,
697 .hw_free = alsa_hw_free,
698 .prepare = alsa_prepare,
699 .trigger = alsa_trigger,
700 .pointer = alsa_pointer,
701 .copy_user = alsa_pb_copy_user,
702 .copy_kernel = alsa_pb_copy_kernel,
703 .fill_silence = alsa_pb_fill_silence,
704 };
705
706 static const struct snd_pcm_ops snd_drv_alsa_capture_ops = {
707 .open = alsa_open,
708 .close = alsa_close,
709 .ioctl = snd_pcm_lib_ioctl,
710 .hw_params = alsa_hw_params,
711 .hw_free = alsa_hw_free,
712 .prepare = alsa_prepare,
713 .trigger = alsa_trigger,
714 .pointer = alsa_pointer,
715 .copy_user = alsa_cap_copy_user,
716 .copy_kernel = alsa_cap_copy_kernel,
717 };
718
719 static int new_pcm_instance(struct xen_snd_front_card_info *card_info,
720 struct xen_front_cfg_pcm_instance *instance_cfg,
721 struct xen_snd_front_pcm_instance_info *pcm_instance_info)
722 {
723 struct snd_pcm *pcm;
724 int ret, i;
725
726 dev_dbg(&card_info->front_info->xb_dev->dev,
727 "New PCM device \"%s\" with id %d playback %d capture %d",
728 instance_cfg->name,
729 instance_cfg->device_id,
730 instance_cfg->num_streams_pb,
731 instance_cfg->num_streams_cap);
732
733 pcm_instance_info->card_info = card_info;
734
735 pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
736
737 if (instance_cfg->num_streams_pb) {
738 pcm_instance_info->streams_pb =
739 devm_kcalloc(&card_info->card->card_dev,
740 instance_cfg->num_streams_pb,
741 sizeof(struct xen_snd_front_pcm_stream_info),
742 GFP_KERNEL);
743 if (!pcm_instance_info->streams_pb)
744 return -ENOMEM;
745 }
746
747 if (instance_cfg->num_streams_cap) {
748 pcm_instance_info->streams_cap =
749 devm_kcalloc(&card_info->card->card_dev,
750 instance_cfg->num_streams_cap,
751 sizeof(struct xen_snd_front_pcm_stream_info),
752 GFP_KERNEL);
753 if (!pcm_instance_info->streams_cap)
754 return -ENOMEM;
755 }
756
757 pcm_instance_info->num_pcm_streams_pb =
758 instance_cfg->num_streams_pb;
759 pcm_instance_info->num_pcm_streams_cap =
760 instance_cfg->num_streams_cap;
761
762 for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
763 pcm_instance_info->streams_pb[i].pcm_hw =
764 instance_cfg->streams_pb[i].pcm_hw;
765 pcm_instance_info->streams_pb[i].index =
766 instance_cfg->streams_pb[i].index;
767 }
768
769 for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
770 pcm_instance_info->streams_cap[i].pcm_hw =
771 instance_cfg->streams_cap[i].pcm_hw;
772 pcm_instance_info->streams_cap[i].index =
773 instance_cfg->streams_cap[i].index;
774 }
775
776 ret = snd_pcm_new(card_info->card, instance_cfg->name,
777 instance_cfg->device_id,
778 instance_cfg->num_streams_pb,
779 instance_cfg->num_streams_cap,
780 &pcm);
781 if (ret < 0)
782 return ret;
783
784 pcm->private_data = pcm_instance_info;
785 pcm->info_flags = 0;
786 /* we want to handle all PCM operations in non-atomic context */
787 pcm->nonatomic = true;
788 strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
789
790 if (instance_cfg->num_streams_pb)
791 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
792 &snd_drv_alsa_playback_ops);
793
794 if (instance_cfg->num_streams_cap)
795 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
796 &snd_drv_alsa_capture_ops);
797
798 pcm_instance_info->pcm = pcm;
799 return 0;
800 }
801
802 int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
803 {
804 struct device *dev = &front_info->xb_dev->dev;
805 struct xen_front_cfg_card *cfg = &front_info->cfg;
806 struct xen_snd_front_card_info *card_info;
807 struct snd_card *card;
808 int ret, i;
809
810 dev_dbg(dev, "Creating virtual sound card\n");
811
812 ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
813 sizeof(struct xen_snd_front_card_info), &card);
814 if (ret < 0)
815 return ret;
816
817 card_info = card->private_data;
818 card_info->front_info = front_info;
819 front_info->card_info = card_info;
820 card_info->card = card;
821 card_info->pcm_instances =
822 devm_kcalloc(dev, cfg->num_pcm_instances,
823 sizeof(struct xen_snd_front_pcm_instance_info),
824 GFP_KERNEL);
825 if (!card_info->pcm_instances) {
826 ret = -ENOMEM;
827 goto fail;
828 }
829
830 card_info->num_pcm_instances = cfg->num_pcm_instances;
831 card_info->pcm_hw = cfg->pcm_hw;
832
833 for (i = 0; i < cfg->num_pcm_instances; i++) {
834 ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
835 &card_info->pcm_instances[i]);
836 if (ret < 0)
837 goto fail;
838 }
839
840 strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
841 strncpy(card->shortname, cfg->name_short, sizeof(card->shortname));
842 strncpy(card->longname, cfg->name_long, sizeof(card->longname));
843
844 ret = snd_card_register(card);
845 if (ret < 0)
846 goto fail;
847
848 return 0;
849
850 fail:
851 snd_card_free(card);
852 return ret;
853 }
854
855 void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
856 {
857 struct xen_snd_front_card_info *card_info;
858 struct snd_card *card;
859
860 card_info = front_info->card_info;
861 if (!card_info)
862 return;
863
864 card = card_info->card;
865 if (!card)
866 return;
867
868 dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",
869 card->number);
870 snd_card_free(card);
871
872 /* Card_info will be freed when destroying front_info->xb_dev->dev. */
873 card_info->card = NULL;
874 }
connection oriented routing