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