sound/virtio/virtio_pcm.c

   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  */
  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                 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(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(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  */
 218 struct 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(-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  */
 238 struct 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(vpcm))
 245                 return vpcm;
 246
 247         vpcm = devm_kzalloc(&vdev->dev, sizeof(*vpcm), GFP_KERNEL);
 248         if (!vpcm)
 249                 return ERR_PTR(-ENOMEM);
 250
 251         vpcm->nid = nid;
 252         list_add_tail(&vpcm->list, &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  */
 264 int 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  */
 308 static 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(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  */
 325 int 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(&vdev->dev, snd->nsubstreams,
 338                                        sizeof(*snd->substreams), GFP_KERNEL);
 339         if (!snd->substreams)
 340                 return -ENOMEM;
 341
 342         info = kcalloc(snd->nsubstreams, sizeof(*info), GFP_KERNEL);
 343         if (!info)
 344                 return -ENOMEM;
 345
 346         rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_PCM_INFO, 0,
 347                                     snd->nsubstreams, sizeof(*info), info);
 348         if (rc)
 349                 goto on_exit;
 350
 351         for (i = 0; i < snd->nsubstreams; ++i) {
 352                 struct virtio_pcm_substream *vss = &snd->substreams[i];
 353                 struct virtio_pcm *vpcm;
 354
 355                 vss->snd = snd;
 356                 vss->sid = i;
 357                 INIT_WORK(&vss->elapsed_period, virtsnd_pcm_period_elapsed);
 358                 init_waitqueue_head(&vss->msg_empty);
 359                 spin_lock_init(&vss->lock);
 360
 361                 rc = virtsnd_pcm_build_hw(vss, &info[i]);
 362                 if (rc)
 363                         goto on_exit;
 364
 365                 vss->nid = le32_to_cpu(info[i].hdr.hda_fn_nid);
 366
 367                 vpcm = virtsnd_pcm_find_or_create(snd, vss->nid);
 368                 if (IS_ERR(vpcm)) {
 369                         rc = PTR_ERR(vpcm);
 370                         goto on_exit;
 371                 }
 372
 373                 switch (info[i].direction) {
 374                 case VIRTIO_SND_D_OUTPUT:
 375                         vss->direction = SNDRV_PCM_STREAM_PLAYBACK;
 376                         break;
 377                 case VIRTIO_SND_D_INPUT:
 378                         vss->direction = SNDRV_PCM_STREAM_CAPTURE;
 379                         break;
 380                 default:
 381                         dev_err(&vdev->dev, "SID %u: unknown direction (%u)\n",
 382                                 vss->sid, info[i].direction);
 383                         rc = -EINVAL;
 384                         goto on_exit;
 385                 }
 386
 387                 vpcm->streams[vss->direction].nsubstreams++;
 388         }
 389
 390 on_exit:
 391         kfree(info);
 392
 393         return rc;
 394 }
 395
 396 /**
 397  * virtsnd_pcm_build_devs() - Build ALSA PCM devices.
 398  * @snd: VirtIO sound device.
 399  *
 400  * Context: Any context that permits to sleep.
 401  * Return: 0 on success, -errno on failure.
 402  */
 403 int virtsnd_pcm_build_devs(struct virtio_snd *snd)
 404 {
 405         struct virtio_device *vdev = snd->vdev;
 406         struct virtio_pcm *vpcm;
 407         u32 i;
 408         int rc;
 409
 410         list_for_each_entry(vpcm, &snd->pcm_list, list) {
 411                 unsigned int npbs =
 412                         vpcm->streams[SNDRV_PCM_STREAM_PLAYBACK].nsubstreams;
 413                 unsigned int ncps =
 414                         vpcm->streams[SNDRV_PCM_STREAM_CAPTURE].nsubstreams;
 415
 416                 if (!npbs && !ncps)
 417                         continue;
 418
 419                 rc = snd_pcm_new(snd->card, VIRTIO_SND_CARD_DRIVER, vpcm->nid,
 420                                  npbs, ncps, &vpcm->pcm);
 421                 if (rc) {
 422                         dev_err(&vdev->dev, "snd_pcm_new[%u] failed: %d\n",
 423                                 vpcm->nid, rc);
 424                         return rc;
 425                 }
 426
 427                 vpcm->pcm->info_flags = 0;
 428                 vpcm->pcm->dev_class = SNDRV_PCM_CLASS_GENERIC;
 429                 vpcm->pcm->dev_subclass = SNDRV_PCM_SUBCLASS_GENERIC_MIX;
 430                 snprintf(vpcm->pcm->name, sizeof(vpcm->pcm->name),
 431                          VIRTIO_SND_PCM_NAME " %u", vpcm->pcm->device);
 432                 vpcm->pcm->private_data = vpcm;
 433                 vpcm->pcm->nonatomic = true;
 434
 435                 for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) {
 436                         struct virtio_pcm_stream *stream = &vpcm->streams[i];
 437
 438                         if (!stream->nsubstreams)
 439                                 continue;
 440
 441                         stream->substreams =
 442                                 devm_kcalloc(&vdev->dev, stream->nsubstreams,
 443                                              sizeof(*stream->substreams),
 444                                              GFP_KERNEL);
 445                         if (!stream->substreams)
 446                                 return -ENOMEM;
 447
 448                         stream->nsubstreams = 0;
 449                 }
 450         }
 451
 452         for (i = 0; i < snd->nsubstreams; ++i) {
 453                 struct virtio_pcm_stream *vs;
 454                 struct virtio_pcm_substream *vss = &snd->substreams[i];
 455
 456                 vpcm = virtsnd_pcm_find(snd, vss->nid);
 457                 if (IS_ERR(vpcm))
 458                         return PTR_ERR(vpcm);
 459
 460                 vs = &vpcm->streams[vss->direction];
 461                 vs->substreams[vs->nsubstreams++] = vss;
 462         }
 463
 464         list_for_each_entry(vpcm, &snd->pcm_list, list) {
 465                 for (i = 0; i < ARRAY_SIZE(vpcm->streams); ++i) {
 466                         struct virtio_pcm_stream *vs = &vpcm->streams[i];
 467                         struct snd_pcm_str *ks = &vpcm->pcm->streams[i];
 468                         struct snd_pcm_substream *kss;
 469
 470                         if (!vs->nsubstreams)
 471                                 continue;
 472
 473                         for (kss = ks->substream; kss; kss = kss->next)
 474                                 vs->substreams[kss->number]->substream = kss;
 475
 476                         snd_pcm_set_ops(vpcm->pcm, i, &virtsnd_pcm_ops[i]);
 477                 }
 478
 479                 snd_pcm_set_managed_buffer_all(vpcm->pcm,
 480                                                SNDRV_DMA_TYPE_VMALLOC, NULL,
 481                                                0, 0);
 482         }
 483
 484         return 0;
 485 }
 486
 487 /**
 488  * virtsnd_pcm_event() - Handle the PCM device event notification.
 489  * @snd: VirtIO sound device.
 490  * @event: VirtIO sound event.
 491  *
 492  * Context: Interrupt context.
 493  */
 494 void virtsnd_pcm_event(struct virtio_snd *snd, struct virtio_snd_event *event)
 495 {
 496         struct virtio_pcm_substream *vss;
 497         u32 sid = le32_to_cpu(event->data);
 498
 499         if (sid >= snd->nsubstreams)
 500                 return;
 501
 502         vss = &snd->substreams[sid];
 503
 504         switch (le32_to_cpu(event->hdr.code)) {
 505         case VIRTIO_SND_EVT_PCM_PERIOD_ELAPSED:
 506                 /* TODO: deal with shmem elapsed period */
 507                 break;
 508         case VIRTIO_SND_EVT_PCM_XRUN:
 509                 spin_lock(&vss->lock);
 510                 if (vss->xfer_enabled)
 511                         vss->xfer_xrun = true;
 512                 spin_unlock(&vss->lock);
 513                 break;
 514         }
 515 }