1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * virtio-snd: Virtio sound device
4 * Copyright (C) 2021 OpenSynergy GmbH
5 */
6#include <linux/moduleparam.h>
7#include <linux/virtio_config.h>
8
9#include "virtio_card.h"
10
11static u32 pcm_buffer_ms = 160;
12module_param(pcm_buffer_ms, uint, 0644);
13MODULE_PARM_DESC(pcm_buffer_ms, "PCM substream buffer time in milliseconds");
14
15static u32 pcm_periods_min = 2;
16module_param(pcm_periods_min, uint, 0644);
17MODULE_PARM_DESC(pcm_periods_min, "Minimum number of PCM periods");
18
19static u32 pcm_periods_max = 16;
20module_param(pcm_periods_max, uint, 0644);
21MODULE_PARM_DESC(pcm_periods_max, "Maximum number of PCM periods");
22
23static u32 pcm_period_ms_min = 10;
24module_param(pcm_period_ms_min, uint, 0644);
25MODULE_PARM_DESC(pcm_period_ms_min, "Minimum PCM period time in milliseconds");
26
27static u32 pcm_period_ms_max = 80;
28module_param(pcm_period_ms_max, uint, 0644);
29MODULE_PARM_DESC(pcm_period_ms_max, "Maximum PCM period time in milliseconds");
30
31/* Map for converting VirtIO format to ALSA format. */
32static const snd_pcm_format_t g_v2a_format_map[] = {
33 [VIRTIO_SND_PCM_FMT_IMA_ADPCM] = SNDRV_PCM_FORMAT_IMA_ADPCM,
34 [VIRTIO_SND_PCM_FMT_MU_LAW] = SNDRV_PCM_FORMAT_MU_LAW,
35 [VIRTIO_SND_PCM_FMT_A_LAW] = SNDRV_PCM_FORMAT_A_LAW,
36 [VIRTIO_SND_PCM_FMT_S8] = SNDRV_PCM_FORMAT_S8,
37 [VIRTIO_SND_PCM_FMT_U8] = SNDRV_PCM_FORMAT_U8,
38 [VIRTIO_SND_PCM_FMT_S16] = SNDRV_PCM_FORMAT_S16_LE,
39 [VIRTIO_SND_PCM_FMT_U16] = SNDRV_PCM_FORMAT_U16_LE,
40 [VIRTIO_SND_PCM_FMT_S18_3] = SNDRV_PCM_FORMAT_S18_3LE,
41 [VIRTIO_SND_PCM_FMT_U18_3] = SNDRV_PCM_FORMAT_U18_3LE,
42 [VIRTIO_SND_PCM_FMT_S20_3] = SNDRV_PCM_FORMAT_S20_3LE,
43 [VIRTIO_SND_PCM_FMT_U20_3] = SNDRV_PCM_FORMAT_U20_3LE,
44 [VIRTIO_SND_PCM_FMT_S24_3] = SNDRV_PCM_FORMAT_S24_3LE,
45 [VIRTIO_SND_PCM_FMT_U24_3] = SNDRV_PCM_FORMAT_U24_3LE,
46 [VIRTIO_SND_PCM_FMT_S20] = SNDRV_PCM_FORMAT_S20_LE,
47 [VIRTIO_SND_PCM_FMT_U20] = SNDRV_PCM_FORMAT_U20_LE,
48 [VIRTIO_SND_PCM_FMT_S24] = SNDRV_PCM_FORMAT_S24_LE,
49 [VIRTIO_SND_PCM_FMT_U24] = SNDRV_PCM_FORMAT_U24_LE,
50 [VIRTIO_SND_PCM_FMT_S32] = SNDRV_PCM_FORMAT_S32_LE,
51 [VIRTIO_SND_PCM_FMT_U32] = SNDRV_PCM_FORMAT_U32_LE,
52 [VIRTIO_SND_PCM_FMT_FLOAT] = SNDRV_PCM_FORMAT_FLOAT_LE,
53 [VIRTIO_SND_PCM_FMT_FLOAT64] = SNDRV_PCM_FORMAT_FLOAT64_LE,
54 [VIRTIO_SND_PCM_FMT_DSD_U8] = SNDRV_PCM_FORMAT_DSD_U8,
55 [VIRTIO_SND_PCM_FMT_DSD_U16] = SNDRV_PCM_FORMAT_DSD_U16_LE,
56 [VIRTIO_SND_PCM_FMT_DSD_U32] = SNDRV_PCM_FORMAT_DSD_U32_LE,
57 [VIRTIO_SND_PCM_FMT_IEC958_SUBFRAME] =
58 SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
59};
60
61/* Map for converting VirtIO frame rate to ALSA frame rate. */
62struct virtsnd_v2a_rate {
63 unsigned int alsa_bit;
64 unsigned int rate;
65};
66
67static const struct virtsnd_v2a_rate g_v2a_rate_map[] = {
68 [VIRTIO_SND_PCM_RATE_5512] = { SNDRV_PCM_RATE_5512, 5512 },
69 [VIRTIO_SND_PCM_RATE_8000] = { SNDRV_PCM_RATE_8000, 8000 },
70 [VIRTIO_SND_PCM_RATE_11025] = { SNDRV_PCM_RATE_11025, 11025 },
71 [VIRTIO_SND_PCM_RATE_16000] = { SNDRV_PCM_RATE_16000, 16000 },
72 [VIRTIO_SND_PCM_RATE_22050] = { SNDRV_PCM_RATE_22050, 22050 },
73 [VIRTIO_SND_PCM_RATE_32000] = { SNDRV_PCM_RATE_32000, 32000 },
74 [VIRTIO_SND_PCM_RATE_44100] = { SNDRV_PCM_RATE_44100, 44100 },
75 [VIRTIO_SND_PCM_RATE_48000] = { SNDRV_PCM_RATE_48000, 48000 },
76 [VIRTIO_SND_PCM_RATE_64000] = { SNDRV_PCM_RATE_64000, 64000 },
77 [VIRTIO_SND_PCM_RATE_88200] = { SNDRV_PCM_RATE_88200, 88200 },
78 [VIRTIO_SND_PCM_RATE_96000] = { SNDRV_PCM_RATE_96000, 96000 },
79 [VIRTIO_SND_PCM_RATE_176400] = { SNDRV_PCM_RATE_176400, 176400 },
80 [VIRTIO_SND_PCM_RATE_192000] = { SNDRV_PCM_RATE_192000, 192000 }
81};
82
83/**
84 * virtsnd_pcm_build_hw() - Parse substream config and build HW descriptor.
85 * @vss: VirtIO substream.
86 * @info: VirtIO substream information entry.
87 *
88 * Context: Any context.
89 * Return: 0 on success, -EINVAL if configuration is invalid.
90 */
91static int virtsnd_pcm_build_hw(struct virtio_pcm_substream *vss,
92 struct virtio_snd_pcm_info *info)
93{
94 struct virtio_device *vdev = vss->snd->vdev;
95 unsigned int i;
96 u64 values;
97 size_t sample_max = 0;
98 size_t sample_min = 0;
99
100 vss->features = le32_to_cpu(info->features);
101
102 /*
103 * TODO: set SNDRV_PCM_INFO_{BATCH,BLOCK_TRANSFER} if device supports
104 * only message-based transport.
105 */
106 vss->hw.info =
107 SNDRV_PCM_INFO_MMAP |
108 SNDRV_PCM_INFO_MMAP_VALID |
109 SNDRV_PCM_INFO_BATCH |
110 SNDRV_PCM_INFO_BLOCK_TRANSFER |
111 SNDRV_PCM_INFO_INTERLEAVED |
112 SNDRV_PCM_INFO_PAUSE |
113 SNDRV_PCM_INFO_NO_REWINDS |
114 SNDRV_PCM_INFO_SYNC_APPLPTR;
115
116 if (!info->channels_min || info->channels_min > info->channels_max) {
117 dev_err(&vdev->dev,
118 "SID %u: invalid channel range [%u %u]\n",
119 vss->sid, info->channels_min, info->channels_max);
120 return -EINVAL;
121 }
122
123 vss->hw.channels_min = info->channels_min;
124 vss->hw.channels_max = info->channels_max;
125
126 values = le64_to_cpu(info->formats);
127
128 vss->hw.formats = 0;
129
130 for (i = 0; i < ARRAY_SIZE(g_v2a_format_map); ++i)
131 if (values & (1ULL << i)) {
132 snd_pcm_format_t alsa_fmt = g_v2a_format_map[i];
133 int bytes = snd_pcm_format_physical_width(format: alsa_fmt) / 8;
134
135 if (!sample_min || sample_min > bytes)
136 sample_min = bytes;
137
138 if (sample_max < bytes)
139 sample_max = bytes;
140
141 vss->hw.formats |= pcm_format_to_bits(pcm_format: alsa_fmt);
142 }
143
144 if (!vss->hw.formats) {
145 dev_err(&vdev->dev,
146 "SID %u: no supported PCM sample formats found\n",
147 vss->sid);
148 return -EINVAL;
149 }
150
151 values = le64_to_cpu(info->rates);
152
153 vss->hw.rates = 0;
154
155 for (i = 0; i < ARRAY_SIZE(g_v2a_rate_map); ++i)
156 if (values & (1ULL << i)) {
157 if (!vss->hw.rate_min ||
158 vss->hw.rate_min > g_v2a_rate_map[i].rate)
159 vss->hw.rate_min = g_v2a_rate_map[i].rate;
160
161 if (vss->hw.rate_max < g_v2a_rate_map[i].rate)
162 vss->hw.rate_max = g_v2a_rate_map[i].rate;
163
164 vss->hw.rates |= g_v2a_rate_map[i].alsa_bit;
165 }
166
167 if (!vss->hw.rates) {
168 dev_err(&vdev->dev,
169 "SID %u: no supported PCM frame rates found\n",
170 vss->sid);
171 return -EINVAL;
172 }
173
174 vss->hw.periods_min = pcm_periods_min;
175 vss->hw.periods_max = pcm_periods_max;
176
177 /*
178 * We must ensure that there is enough space in the buffer to store
179 * pcm_buffer_ms ms for the combination (Cmax, Smax, Rmax), where:
180 * Cmax = maximum supported number of channels,
181 * Smax = maximum supported sample size in bytes,
182 * Rmax = maximum supported frame rate.
183 */
184 vss->hw.buffer_bytes_max =
185 PAGE_ALIGN(sample_max * vss->hw.channels_max * pcm_buffer_ms *
186 (vss->hw.rate_max / MSEC_PER_SEC));
187
188 /*
189 * We must ensure that the minimum period size is enough to store
190 * pcm_period_ms_min ms for the combination (Cmin, Smin, Rmin), where:
191 * Cmin = minimum supported number of channels,
192 * Smin = minimum supported sample size in bytes,
193 * Rmin = minimum supported frame rate.
194 */
195 vss->hw.period_bytes_min =
196 sample_min * vss->hw.channels_min * pcm_period_ms_min *
197 (vss->hw.rate_min / MSEC_PER_SEC);
198
199 /*
200 * We must ensure that the maximum period size is enough to store
201 * pcm_period_ms_max ms for the combination (Cmax, Smax, Rmax).
202 */
203 vss->hw.period_bytes_max =
204 sample_max * vss->hw.channels_max * pcm_period_ms_max *
205 (vss->hw.rate_max / MSEC_PER_SEC);
206
207 return 0;
208}
209
210/**
211 * virtsnd_pcm_find() - Find the PCM device for the specified node ID.
212 * @snd: VirtIO sound device.
213 * @nid: Function node ID.
214 *
215 * Context: Any context.
216 * Return: a pointer to the PCM device or ERR_PTR(-ENOENT).
217 */
218struct virtio_pcm *virtsnd_pcm_find(struct virtio_snd *snd, u32 nid)
219{
220 struct virtio_pcm *vpcm;
221
222 list_for_each_entry(vpcm, &snd->pcm_list, list)
223 if (vpcm->nid == nid)
224 return vpcm;
225
226 return ERR_PTR(error: -ENOENT);
227}
228
229/**
230 * virtsnd_pcm_find_or_create() - Find or create the PCM device for the
231 * specified node ID.
232 * @snd: VirtIO sound device.
233 * @nid: Function node ID.
234 *
235 * Context: Any context that permits to sleep.
236 * Return: a pointer to the PCM device or ERR_PTR(-errno).
237 */
238struct virtio_pcm *virtsnd_pcm_find_or_create(struct virtio_snd *snd, u32 nid)
239{
240 struct virtio_device *vdev = snd->vdev;
241 struct virtio_pcm *vpcm;
242
243 vpcm = virtsnd_pcm_find(snd, nid);
244 if (!IS_ERR(ptr: vpcm))
245 return vpcm;
246
247 vpcm = devm_kzalloc(dev: &vdev->dev, size: sizeof(*vpcm), GFP_KERNEL);
248 if (!vpcm)
249 return ERR_PTR(error: -ENOMEM);
250
251 vpcm->nid = nid;
252 list_add_tail(new: &vpcm->list, head: &snd->pcm_list);
253
254 return vpcm;
255}
256
257/**
258 * virtsnd_pcm_validate() - Validate if the device can be started.
259 * @vdev: VirtIO parent device.
260 *
261 * Context: Any context.
262 * Return: 0 on success, -EINVAL on failure.
263 */
264int virtsnd_pcm_validate(struct virtio_device *vdev)
265{
266 if (pcm_periods_min < 2 || pcm_periods_min > pcm_periods_max) {
267 dev_err(&vdev->dev,
268 "invalid range [%u %u] of the number of PCM periods\n",
269 pcm_periods_min, pcm_periods_max);
270 return -EINVAL;
271 }
272
273 if (!pcm_period_ms_min || pcm_period_ms_min > pcm_period_ms_max) {
274 dev_err(&vdev->dev,
275 "invalid range [%u %u] of the size of the PCM period\n",
276 pcm_period_ms_min, pcm_period_ms_max);
277 return -EINVAL;
278 }
279
280 if (pcm_buffer_ms < pcm_periods_min * pcm_period_ms_min) {
281 dev_err(&vdev->dev,
282 "pcm_buffer_ms(=%u) value cannot be < %u ms\n",
283 pcm_buffer_ms, pcm_periods_min * pcm_period_ms_min);
284 return -EINVAL;
285 }
286
287 if (pcm_period_ms_max > pcm_buffer_ms / 2) {
288 dev_err(&vdev->dev,
289 "pcm_period_ms_max(=%u) value cannot be > %u ms\n",
290 pcm_period_ms_max, pcm_buffer_ms / 2);
291 return -EINVAL;
292 }
293
294 return 0;
295}
296
297/**
298 * virtsnd_pcm_period_elapsed() - Kernel work function to handle the elapsed
299 * period state.
300 * @work: Elapsed period work.
301 *
302 * The main purpose of this function is to call snd_pcm_period_elapsed() in
303 * a process context, not in an interrupt context. This is necessary because PCM
304 * devices operate in non-atomic mode.
305 *
306 * Context: Process context.
307 */
308static void virtsnd_pcm_period_elapsed(struct work_struct *work)
309{
310 struct virtio_pcm_substream *vss =
311 container_of(work, struct virtio_pcm_substream, elapsed_period);
312
313 snd_pcm_period_elapsed(substream: vss->substream);
314}
315
316/**
317 * virtsnd_pcm_parse_cfg() - Parse the stream configuration.
318 * @snd: VirtIO sound device.
319 *
320 * This function is called during initial device initialization.
321 *
322 * Context: Any context that permits to sleep.
323 * Return: 0 on success, -errno on failure.
324 */
325int virtsnd_pcm_parse_cfg(struct virtio_snd *snd)
326{
327 struct virtio_device *vdev = snd->vdev;
328 struct virtio_snd_pcm_info *info;
329 u32 i;
330 int rc;
331
332 virtio_cread_le(vdev, struct virtio_snd_config, streams,
333 &snd->nsubstreams);
334 if (!snd->nsubstreams)
335 return 0;
336
337 snd->substreams = devm_kcalloc(dev: &vdev->dev, n: snd->nsubstreams,
338 size: sizeof(*snd->substreams), GFP_KERNEL);
339 if (!snd->substreams)
340 return -ENOMEM;
341
342 /*
343 * Initialize critical substream fields early in case we hit an
344 * error path and end up trying to clean up uninitialized structures
345 * elsewhere.
346 */
347 for (i = 0; i < snd->nsubstreams; ++i) {
348 struct virtio_pcm_substream *vss = &snd->substreams[i];
349
350 vss->snd = snd;
351 vss->sid = i;
352 INIT_WORK(&vss->elapsed_period, virtsnd_pcm_period_elapsed);
353 init_waitqueue_head(&vss->msg_empty);
354 spin_lock_init(&vss->lock);
355 }
356
357 info = kcalloc(snd->nsubstreams, sizeof(*info), GFP_KERNEL);
358 if (!info)
359 return -ENOMEM;
360
361 rc = virtsnd_ctl_query_info(snd, command: VIRTIO_SND_R_PCM_INFO, start_id: 0,
362 count: snd->nsubstreams, size: sizeof(*info), info);
363 if (rc)
364 goto on_exit;
365
366 for (i = 0; i < snd->nsubstreams; ++i) {
367 struct virtio_pcm_substream *vss = &snd->substreams[i];
368 struct virtio_pcm *vpcm;
369
370 rc = virtsnd_pcm_build_hw(vss, info: &info[i]);
371 if (rc)
372 goto on_exit;
373
374 vss->nid = le32_to_cpu(info[i].hdr.hda_fn_nid);
375
376 vpcm = virtsnd_pcm_find_or_create(snd, nid: vss->nid);
377 if (IS_ERR(ptr: vpcm)) {
378 rc = PTR_ERR(ptr: vpcm);
379 goto on_exit;
380 }
381
382 switch (info[i].direction) {
383 case VIRTIO_SND_D_OUTPUT:
384 vss->direction = SNDRV_PCM_STREAM_PLAYBACK;
385 break;
386 case VIRTIO_SND_D_INPUT:
387 vss->direction = SNDRV_PCM_STREAM_CAPTURE;
388 break;
389 default:
390 dev_err(&vdev->dev, "SID %u: unknown direction (%u)\n",
391 vss->sid, info[i].direction);
392 rc = -EINVAL;
393 goto on_exit;
394 }
395
396 vpcm->streams[vss->direction].nsubstreams++;
397 }
398
399on_exit:
400 kfree(objp: info);
401
402 return rc;
403}
404
405/**
406 * virtsnd_pcm_build_devs() - Build ALSA PCM devices.
407 * @snd: VirtIO sound device.
408 *
409 * Context: Any context that permits to sleep.
410 * Return: 0 on success, -errno on failure.
411 */
412int virtsnd_pcm_build_devs(struct virtio_snd *snd)
413{
414 struct virtio_device *vdev = snd->vdev;
415 struct virtio_pcm *vpcm;
416 u32 i;
417 int rc;
418
419 list_for_each_entry(vpcm, &snd->pcm_list, list) {
420 unsigned int npbs =
421 vpcm->streams[SNDRV_PCM_STREAM_PLAYBACK].nsubstreams;
422 unsigned int ncps =
423 vpcm->streams[SNDRV_PCM_STREAM_CAPTURE].nsubstreams;
424
425 if (!npbs && !ncps)
426 continue;
427
428 rc = snd_pcm_new(card: snd->card, VIRTIO_SND_CARD_DRIVER, device: vpcm->nid,
429 playback_count: npbs, capture_count: ncps, rpcm: &vpcm->pcm);
430 if (rc) {
431 dev_err(&vdev->dev, "snd_pcm_new[%u] failed: %d\n",
432 vpcm->nid, rc);
433 return rc;
434 }
435
436 vpcm->pcm->info_flags = 0;
437 vpcm->pcm->dev_class = SNDRV_PCM_CLASS_GENERIC;
438 vpcm->pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
439 snprintf(buf: vpcm->pcm->name, size: sizeof(vpcm->pcm->name),
440 VIRTIO_SND_PCM_NAME " %u", vpcm->pcm->device);
441 vpcm->pcm->private_data = vpcm;
442 vpcm->pcm->nonatomic = true;
443
444 for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) {
445 struct virtio_pcm_stream *stream = &vpcm->streams[i];
446
447 if (!stream->nsubstreams)
448 continue;
449
450 stream->substreams =
451 devm_kcalloc(dev: &vdev->dev, n: stream->nsubstreams,
452 size: sizeof(*stream->substreams),
453 GFP_KERNEL);
454 if (!stream->substreams)
455 return -ENOMEM;
456
457 stream->nsubstreams = 0;
458 }
459 }
460
461 for (i = 0; i < snd->nsubstreams; ++i) {
462 struct virtio_pcm_stream *vs;
463 struct virtio_pcm_substream *vss = &snd->substreams[i];
464
465 vpcm = virtsnd_pcm_find(snd, nid: vss->nid);
466 if (IS_ERR(ptr: vpcm))
467 return PTR_ERR(ptr: vpcm);
468
469 vs = &vpcm->streams[vss->direction];
470 vs->substreams[vs->nsubstreams++] = vss;
471 }
472
473 list_for_each_entry(vpcm, &snd->pcm_list, list) {
474 for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) {
475 struct virtio_pcm_stream *vs = &vpcm->streams[i];
476 struct snd_pcm_str *ks = &vpcm->pcm->streams[i];
477 struct snd_pcm_substream *kss;
478
479 if (!vs->nsubstreams)
480 continue;
481
482 for (kss = ks->substream; kss; kss = kss->next)
483 vs->substreams[kss->number]->substream = kss;
484
485 snd_pcm_set_ops(pcm: vpcm->pcm, direction: i, ops: &virtsnd_pcm_ops[i]);
486 }
487
488 snd_pcm_set_managed_buffer_all(pcm: vpcm->pcm,
489 SNDRV_DMA_TYPE_VMALLOC, NULL,
490 size: 0, max: 0);
491 }
492
493 return 0;
494}
495
496/**
497 * virtsnd_pcm_event() - Handle the PCM device event notification.
498 * @snd: VirtIO sound device.
499 * @event: VirtIO sound event.
500 *
501 * Context: Interrupt context.
502 */
503void virtsnd_pcm_event(struct virtio_snd *snd, struct virtio_snd_event *event)
504{
505 struct virtio_pcm_substream *vss;
506 u32 sid = le32_to_cpu(event->data);
507
508 if (sid >= snd->nsubstreams)
509 return;
510
511 vss = &snd->substreams[sid];
512
513 switch (le32_to_cpu(event->hdr.code)) {
514 case VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED:
515 /* TODO: deal with shmem elapsed period */
516 break;
517 case VIRTIO_SND_EVT_PCM_XRUN:
518 scoped_guard(spinlock, &vss->lock) {
519 if (vss->xfer_enabled)
520 vss->xfer_xrun = true;
521 }
522 break;
523 }
524}
525

source code of linux/sound/virtio/virtio_pcm.c