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
11 static u32 pcm_buffer_ms = 160;
12 module_param(pcm_buffer_ms, uint, 0644);
13 MODULE_PARM_DESC(pcm_buffer_ms, "PCM substream buffer time in milliseconds");
14
15 static u32 pcm_periods_min = 2;
16 module_param(pcm_periods_min, uint, 0644);
17 MODULE_PARM_DESC(pcm_periods_min, "Minimum number of PCM periods");
18
19 static u32 pcm_periods_max = 16;
20 module_param(pcm_periods_max, uint, 0644);
21 MODULE_PARM_DESC(pcm_periods_max, "Maximum number of PCM periods");
22
23 static u32 pcm_period_ms_min = 10;
24 module_param(pcm_period_ms_min, uint, 0644);
25 MODULE_PARM_DESC(pcm_period_ms_min, "Minimum PCM period time in milliseconds");
26
27 static u32 pcm_period_ms_max = 80;
28 module_param(pcm_period_ms_max, uint, 0644);
29 MODULE_PARM_DESC(pcm_period_ms_max, "Maximum PCM period time in milliseconds");
30
31 /* Map for converting VirtIO format to ALSA format. */
32 static 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. */
62 struct virtsnd_v2a_rate {
63 unsigned int alsa_bit;
64 unsigned int rate;
65 };
66
67 static 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 */
virtsnd_pcm_build_hw(struct virtio_pcm_substream * vss,struct virtio_snd_pcm_info * info)91 static 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
114 if (!info->channels_min || info->channels_min > info->channels_max) {
115 dev_err(&vdev->dev,
116 "SID %u: invalid channel range [%u %u]\n",
117 vss->sid, info->channels_min, info->channels_max);
118 return -EINVAL;
119 }
120
121 vss->hw.channels_min = info->channels_min;
122 vss->hw.channels_max = info->channels_max;
123
124 values = le64_to_cpu(info->formats);
125
126 vss->hw.formats = 0;
127
128 for (i = 0; i < ARRAY_SIZE(g_v2a_format_map); ++i)
129 if (values & (1ULL << i)) {
130 snd_pcm_format_t alsa_fmt = g_v2a_format_map[i];
131 int bytes = snd_pcm_format_physical_width(alsa_fmt) / 8;
132
133 if (!sample_min || sample_min > bytes)
134 sample_min = bytes;
135
136 if (sample_max < bytes)
137 sample_max = bytes;
138
139 vss->hw.formats |= pcm_format_to_bits(alsa_fmt);
140 }
141
142 if (!vss->hw.formats) {
143 dev_err(&vdev->dev,
144 "SID %u: no supported PCM sample formats found\n",
145 vss->sid);
146 return -EINVAL;
147 }
148
149 values = le64_to_cpu(info->rates);
150
151 vss->hw.rates = 0;
152
153 for (i = 0; i < ARRAY_SIZE(g_v2a_rate_map); ++i)
154 if (values & (1ULL << i)) {
155 if (!vss->hw.rate_min ||
156 vss->hw.rate_min > g_v2a_rate_map[i].rate)
157 vss->hw.rate_min = g_v2a_rate_map[i].rate;
158
159 if (vss->hw.rate_max < g_v2a_rate_map[i].rate)
160 vss->hw.rate_max = g_v2a_rate_map[i].rate;
161
162 vss->hw.rates |= g_v2a_rate_map[i].alsa_bit;
163 }
164
165 if (!vss->hw.rates) {
166 dev_err(&vdev->dev,
167 "SID %u: no supported PCM frame rates found\n",
168 vss->sid);
169 return -EINVAL;
170 }
171
172 vss->hw.periods_min = pcm_periods_min;
173 vss->hw.periods_max = pcm_periods_max;
174
175 /*
176 * We must ensure that there is enough space in the buffer to store
177 * pcm_buffer_ms ms for the combination (Cmax, Smax, Rmax), where:
178 * Cmax = maximum supported number of channels,
179 * Smax = maximum supported sample size in bytes,
180 * Rmax = maximum supported frame rate.
181 */
182 vss->hw.buffer_bytes_max =
183 PAGE_ALIGN(sample_max * vss->hw.channels_max * pcm_buffer_ms *
184 (vss->hw.rate_max / MSEC_PER_SEC));
185
186 /*
187 * We must ensure that the minimum period size is enough to store
188 * pcm_period_ms_min ms for the combination (Cmin, Smin, Rmin), where:
189 * Cmin = minimum supported number of channels,
190 * Smin = minimum supported sample size in bytes,
191 * Rmin = minimum supported frame rate.
192 */
193 vss->hw.period_bytes_min =
194 sample_min * vss->hw.channels_min * pcm_period_ms_min *
195 (vss->hw.rate_min / MSEC_PER_SEC);
196
197 /*
198 * We must ensure that the maximum period size is enough to store
199 * pcm_period_ms_max ms for the combination (Cmax, Smax, Rmax).
200 */
201 vss->hw.period_bytes_max =
202 sample_max * vss->hw.channels_max * pcm_period_ms_max *
203 (vss->hw.rate_max / MSEC_PER_SEC);
204
205 return 0;
206 }
207
208 /**
209 * virtsnd_pcm_find() - Find the PCM device for the specified node ID.
210 * @snd: VirtIO sound device.
211 * @nid: Function node ID.
212 *
213 * Context: Any context.
214 * Return: a pointer to the PCM device or ERR_PTR(-ENOENT).
215 */
virtsnd_pcm_find(struct virtio_snd * snd,u32 nid)216 struct virtio_pcm *virtsnd_pcm_find(struct virtio_snd *snd, u32 nid)
217 {
218 struct virtio_pcm *vpcm;
219
220 list_for_each_entry(vpcm, &snd->pcm_list, list)
221 if (vpcm->nid == nid)
222 return vpcm;
223
224 return ERR_PTR(-ENOENT);
225 }
226
227 /**
228 * virtsnd_pcm_find_or_create() - Find or create the PCM device for the
229 * specified node ID.
230 * @snd: VirtIO sound device.
231 * @nid: Function node ID.
232 *
233 * Context: Any context that permits to sleep.
234 * Return: a pointer to the PCM device or ERR_PTR(-errno).
235 */
virtsnd_pcm_find_or_create(struct virtio_snd * snd,u32 nid)236 struct virtio_pcm *virtsnd_pcm_find_or_create(struct virtio_snd *snd, u32 nid)
237 {
238 struct virtio_device *vdev = snd->vdev;
239 struct virtio_pcm *vpcm;
240
241 vpcm = virtsnd_pcm_find(snd, nid);
242 if (!IS_ERR(vpcm))
243 return vpcm;
244
245 vpcm = devm_kzalloc(&vdev->dev, sizeof(*vpcm), GFP_KERNEL);
246 if (!vpcm)
247 return ERR_PTR(-ENOMEM);
248
249 vpcm->nid = nid;
250 list_add_tail(&vpcm->list, &snd->pcm_list);
251
252 return vpcm;
253 }
254
255 /**
256 * virtsnd_pcm_validate() - Validate if the device can be started.
257 * @vdev: VirtIO parent device.
258 *
259 * Context: Any context.
260 * Return: 0 on success, -EINVAL on failure.
261 */
virtsnd_pcm_validate(struct virtio_device * vdev)262 int virtsnd_pcm_validate(struct virtio_device *vdev)
263 {
264 if (pcm_periods_min < 2 || pcm_periods_min > pcm_periods_max) {
265 dev_err(&vdev->dev,
266 "invalid range [%u %u] of the number of PCM periods\n",
267 pcm_periods_min, pcm_periods_max);
268 return -EINVAL;
269 }
270
271 if (!pcm_period_ms_min || pcm_period_ms_min > pcm_period_ms_max) {
272 dev_err(&vdev->dev,
273 "invalid range [%u %u] of the size of the PCM period\n",
274 pcm_period_ms_min, pcm_period_ms_max);
275 return -EINVAL;
276 }
277
278 if (pcm_buffer_ms < pcm_periods_min * pcm_period_ms_min) {
279 dev_err(&vdev->dev,
280 "pcm_buffer_ms(=%u) value cannot be < %u ms\n",
281 pcm_buffer_ms, pcm_periods_min * pcm_period_ms_min);
282 return -EINVAL;
283 }
284
285 if (pcm_period_ms_max > pcm_buffer_ms / 2) {
286 dev_err(&vdev->dev,
287 "pcm_period_ms_max(=%u) value cannot be > %u ms\n",
288 pcm_period_ms_max, pcm_buffer_ms / 2);
289 return -EINVAL;
290 }
291
292 return 0;
293 }
294
295 /**
296 * virtsnd_pcm_period_elapsed() - Kernel work function to handle the elapsed
297 * period state.
298 * @work: Elapsed period work.
299 *
300 * The main purpose of this function is to call snd_pcm_period_elapsed() in
301 * a process context, not in an interrupt context. This is necessary because PCM
302 * devices operate in non-atomic mode.
303 *
304 * Context: Process context.
305 */
virtsnd_pcm_period_elapsed(struct work_struct * work)306 static void virtsnd_pcm_period_elapsed(struct work_struct *work)
307 {
308 struct virtio_pcm_substream *vss =
309 container_of(work, struct virtio_pcm_substream, elapsed_period);
310
311 snd_pcm_period_elapsed(vss->substream);
312 }
313
314 /**
315 * virtsnd_pcm_parse_cfg() - Parse the stream configuration.
316 * @snd: VirtIO sound device.
317 *
318 * This function is called during initial device initialization.
319 *
320 * Context: Any context that permits to sleep.
321 * Return: 0 on success, -errno on failure.
322 */
virtsnd_pcm_parse_cfg(struct virtio_snd * snd)323 int virtsnd_pcm_parse_cfg(struct virtio_snd *snd)
324 {
325 struct virtio_device *vdev = snd->vdev;
326 struct virtio_snd_pcm_info *info;
327 u32 i;
328 int rc;
329
330 virtio_cread_le(vdev, struct virtio_snd_config, streams,
331 &snd->nsubstreams);
332 if (!snd->nsubstreams)
333 return 0;
334
335 snd->substreams = devm_kcalloc(&vdev->dev, snd->nsubstreams,
336 sizeof(*snd->substreams), GFP_KERNEL);
337 if (!snd->substreams)
338 return -ENOMEM;
339
340 /*
341 * Initialize critical substream fields early in case we hit an
342 * error path and end up trying to clean up uninitialized structures
343 * elsewhere.
344 */
345 for (i = 0; i < snd->nsubstreams; ++i) {
346 struct virtio_pcm_substream *vss = &snd->substreams[i];
347
348 vss->snd = snd;
349 vss->sid = i;
350 INIT_WORK(&vss->elapsed_period, virtsnd_pcm_period_elapsed);
351 init_waitqueue_head(&vss->msg_empty);
352 spin_lock_init(&vss->lock);
353 }
354
355 info = kcalloc(snd->nsubstreams, sizeof(*info), GFP_KERNEL);
356 if (!info)
357 return -ENOMEM;
358
359 rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_PCM_INFO, 0,
360 snd->nsubstreams, sizeof(*info), info);
361 if (rc)
362 goto on_exit;
363
364 for (i = 0; i < snd->nsubstreams; ++i) {
365 struct virtio_pcm_substream *vss = &snd->substreams[i];
366 struct virtio_pcm *vpcm;
367
368 rc = virtsnd_pcm_build_hw(vss, &info[i]);
369 if (rc)
370 goto on_exit;
371
372 vss->nid = le32_to_cpu(info[i].hdr.hda_fn_nid);
373
374 vpcm = virtsnd_pcm_find_or_create(snd, vss->nid);
375 if (IS_ERR(vpcm)) {
376 rc = PTR_ERR(vpcm);
377 goto on_exit;
378 }
379
380 switch (info[i].direction) {
381 case VIRTIO_SND_D_OUTPUT:
382 vss->direction = SNDRV_PCM_STREAM_PLAYBACK;
383 break;
384 case VIRTIO_SND_D_INPUT:
385 vss->direction = SNDRV_PCM_STREAM_CAPTURE;
386 break;
387 default:
388 dev_err(&vdev->dev, "SID %u: unknown direction (%u)\n",
389 vss->sid, info[i].direction);
390 rc = -EINVAL;
391 goto on_exit;
392 }
393
394 vpcm->streams[vss->direction].nsubstreams++;
395 }
396
397 on_exit:
398 kfree(info);
399
400 return rc;
401 }
402
403 /**
404 * virtsnd_pcm_build_devs() - Build ALSA PCM devices.
405 * @snd: VirtIO sound device.
406 *
407 * Context: Any context that permits to sleep.
408 * Return: 0 on success, -errno on failure.
409 */
virtsnd_pcm_build_devs(struct virtio_snd * snd)410 int virtsnd_pcm_build_devs(struct virtio_snd *snd)
411 {
412 struct virtio_device *vdev = snd->vdev;
413 struct virtio_pcm *vpcm;
414 u32 i;
415 int rc;
416
417 list_for_each_entry(vpcm, &snd->pcm_list, list) {
418 unsigned int npbs =
419 vpcm->streams[SNDRV_PCM_STREAM_PLAYBACK].nsubstreams;
420 unsigned int ncps =
421 vpcm->streams[SNDRV_PCM_STREAM_CAPTURE].nsubstreams;
422
423 if (!npbs && !ncps)
424 continue;
425
426 rc = snd_pcm_new(snd->card, VIRTIO_SND_CARD_DRIVER, vpcm->nid,
427 npbs, ncps, &vpcm->pcm);
428 if (rc) {
429 dev_err(&vdev->dev, "snd_pcm_new[%u] failed: %d\n",
430 vpcm->nid, rc);
431 return rc;
432 }
433
434 vpcm->pcm->info_flags = 0;
435 vpcm->pcm->dev_class = SNDRV_PCM_CLASS_GENERIC;
436 vpcm->pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
437 snprintf(vpcm->pcm->name, sizeof(vpcm->pcm->name),
438 VIRTIO_SND_PCM_NAME " %u", vpcm->pcm->device);
439 vpcm->pcm->private_data = vpcm;
440 vpcm->pcm->nonatomic = true;
441
442 for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) {
443 struct virtio_pcm_stream *stream = &vpcm->streams[i];
444
445 if (!stream->nsubstreams)
446 continue;
447
448 stream->substreams =
449 devm_kcalloc(&vdev->dev, stream->nsubstreams,
450 sizeof(*stream->substreams),
451 GFP_KERNEL);
452 if (!stream->substreams)
453 return -ENOMEM;
454
455 stream->nsubstreams = 0;
456 }
457 }
458
459 for (i = 0; i < snd->nsubstreams; ++i) {
460 struct virtio_pcm_stream *vs;
461 struct virtio_pcm_substream *vss = &snd->substreams[i];
462
463 vpcm = virtsnd_pcm_find(snd, vss->nid);
464 if (IS_ERR(vpcm))
465 return PTR_ERR(vpcm);
466
467 vs = &vpcm->streams[vss->direction];
468 vs->substreams[vs->nsubstreams++] = vss;
469 }
470
471 list_for_each_entry(vpcm, &snd->pcm_list, list) {
472 for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) {
473 struct virtio_pcm_stream *vs = &vpcm->streams[i];
474 struct snd_pcm_str *ks = &vpcm->pcm->streams[i];
475 struct snd_pcm_substream *kss;
476
477 if (!vs->nsubstreams)
478 continue;
479
480 for (kss = ks->substream; kss; kss = kss->next)
481 vs->substreams[kss->number]->substream = kss;
482
483 snd_pcm_set_ops(vpcm->pcm, i, &virtsnd_pcm_ops);
484 }
485
486 snd_pcm_set_managed_buffer_all(vpcm->pcm,
487 SNDRV_DMA_TYPE_VMALLOC, NULL,
488 0, 0);
489 }
490
491 return 0;
492 }
493
494 /**
495 * virtsnd_pcm_event() - Handle the PCM device event notification.
496 * @snd: VirtIO sound device.
497 * @event: VirtIO sound event.
498 *
499 * Context: Interrupt context.
500 */
virtsnd_pcm_event(struct virtio_snd * snd,struct virtio_snd_event * event)501 void virtsnd_pcm_event(struct virtio_snd *snd, struct virtio_snd_event *event)
502 {
503 struct virtio_pcm_substream *vss;
504 u32 sid = le32_to_cpu(event->data);
505
506 if (sid >= snd->nsubstreams)
507 return;
508
509 vss = &snd->substreams[sid];
510
511 switch (le32_to_cpu(event->hdr.code)) {
512 case VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED:
513 /* TODO: deal with shmem elapsed period */
514 break;
515 case VIRTIO_SND_EVT_PCM_XRUN:
516 spin_lock(&vss->lock);
517 if (vss->xfer_enabled)
518 vss->xfer_xrun = true;
519 spin_unlock(&vss->lock);
520 break;
521 }
522 }
523