sound/soc/soc-generic-dmaengine-pcm.c

   1 /*
   2  *  Copyright (C) 2013, Analog Devices Inc.
   3  *      Author: Lars-Peter Clausen <lars@metafoo.de>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify it
   6  *  under  the terms of the GNU General  Public License as published by the
   7  *  Free Software Foundation;  either version 2 of the License, or (at your
   8  *  option) any later version.
   9  *
  10  *  You should have received a copy of the GNU General Public License along
  11  *  with this program; if not, write to the Free Software Foundation, Inc.,
  12  *  675 Mass Ave, Cambridge, MA 02139, USA.
  13  *
  14  */
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/dmaengine.h>
  18 #include <linux/slab.h>
  19 #include <sound/pcm.h>
  20 #include <sound/pcm_params.h>
  21 #include <sound/soc.h>
  22 #include <linux/dma-mapping.h>
  23 #include <linux/of.h>
  24
  25 #include <sound/dmaengine_pcm.h>
  26
  27 struct dmaengine_pcm {
  28         struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
  29         const struct snd_dmaengine_pcm_config *config;
  30         struct snd_soc_platform platform;
  31         unsigned int flags;
  32 };
  33
  34 static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p)
  35 {
  36         return container_of(p, struct dmaengine_pcm, platform);
  37 }
  38
  39 static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
  40         struct snd_pcm_substream *substream)
  41 {
  42         if (!pcm->chan[substream->stream])
  43                 return NULL;
  44
  45         return pcm->chan[substream->stream]->device->dev;
  46 }
  47
  48 /**
  49  * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
  50  * @substream: PCM substream
  51  * @params: hw_params
  52  * @slave_config: DMA slave config to prepare
  53  *
  54  * This function can be used as a generic prepare_slave_config callback for
  55  * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
  56  * DAI DMA data. Internally the function will first call
  57  * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
  58  * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
  59  * remaining fields based on the DAI DMA data.
  60  */
  61 int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
  62         struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
  63 {
  64         struct snd_soc_pcm_runtime *rtd = substream->private_data;
  65         struct snd_dmaengine_dai_dma_data *dma_data;
  66         int ret;
  67
  68         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
  69
  70         ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
  71         if (ret)
  72                 return ret;
  73
  74         snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
  75                 slave_config);
  76
  77         return 0;
  78 }
  79 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
  80
  81 static int dmaengine_pcm_hw_params(struct snd_pcm_substream *substream,
  82         struct snd_pcm_hw_params *params)
  83 {
  84         struct snd_soc_pcm_runtime *rtd = substream->private_data;
  85         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
  86         struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
  87         int (*prepare_slave_config)(struct snd_pcm_substream *substream,
  88                         struct snd_pcm_hw_params *params,
  89                         struct dma_slave_config *slave_config);
  90         struct dma_slave_config slave_config;
  91         int ret;
  92
  93         memset(&slave_config, 0, sizeof(slave_config));
  94
  95         if (!pcm->config)
  96                 prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
  97         else
  98                 prepare_slave_config = pcm->config->prepare_slave_config;
  99
 100         if (prepare_slave_config) {
 101                 ret = prepare_slave_config(substream, params, &slave_config);
 102                 if (ret)
 103                         return ret;
 104
 105                 ret = dmaengine_slave_config(chan, &slave_config);
 106                 if (ret)
 107                         return ret;
 108         }
 109
 110         return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
 111 }
 112
 113 static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream)
 114 {
 115         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 116         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 117         struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
 118         struct dma_chan *chan = pcm->chan[substream->stream];
 119         struct snd_dmaengine_dai_dma_data *dma_data;
 120         struct dma_slave_caps dma_caps;
 121         struct snd_pcm_hardware hw;
 122         int ret;
 123
 124         if (pcm->config && pcm->config->pcm_hardware)
 125                 return snd_soc_set_runtime_hwparams(substream,
 126                                 pcm->config->pcm_hardware);
 127
 128         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 129
 130         memset(&hw, 0, sizeof(hw));
 131         hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 132                         SNDRV_PCM_INFO_INTERLEAVED;
 133         hw.periods_min = 2;
 134         hw.periods_max = UINT_MAX;
 135         hw.period_bytes_min = 256;
 136         hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
 137         hw.buffer_bytes_max = SIZE_MAX;
 138         hw.fifo_size = dma_data->fifo_size;
 139
 140         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
 141                 hw.info |= SNDRV_PCM_INFO_BATCH;
 142
 143         ret = dma_get_slave_caps(chan, &dma_caps);
 144         if (ret == 0) {
 145                 if (dma_caps.cmd_pause)
 146                         hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
 147         }
 148
 149         return snd_soc_set_runtime_hwparams(substream, &hw);
 150 }
 151
 152 static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
 153 {
 154         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 155         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 156         struct dma_chan *chan = pcm->chan[substream->stream];
 157         int ret;
 158
 159         ret = dmaengine_pcm_set_runtime_hwparams(substream);
 160         if (ret)
 161                 return ret;
 162
 163         return snd_dmaengine_pcm_open(substream, chan);
 164 }
 165
 166 static void dmaengine_pcm_free(struct snd_pcm *pcm)
 167 {
 168         snd_pcm_lib_preallocate_free_for_all(pcm);
 169 }
 170
 171 static struct dma_chan *dmaengine_pcm_compat_request_channel(
 172         struct snd_soc_pcm_runtime *rtd,
 173         struct snd_pcm_substream *substream)
 174 {
 175         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 176         struct snd_dmaengine_dai_dma_data *dma_data;
 177
 178         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 179
 180         if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
 181                 return pcm->chan[0];
 182
 183         if (pcm->config->compat_request_channel)
 184                 return pcm->config->compat_request_channel(rtd, substream);
 185
 186         return snd_dmaengine_pcm_request_channel(pcm->config->compat_filter_fn,
 187                                                  dma_data->filter_data);
 188 }
 189
 190 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
 191 {
 192         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 193         const struct snd_dmaengine_pcm_config *config = pcm->config;
 194         struct device *dev = rtd->platform->dev;
 195         struct snd_dmaengine_dai_dma_data *dma_data;
 196         struct snd_pcm_substream *substream;
 197         size_t prealloc_buffer_size;
 198         size_t max_buffer_size;
 199         unsigned int i;
 200         int ret;
 201
 202         if (config && config->prealloc_buffer_size) {
 203                 prealloc_buffer_size = config->prealloc_buffer_size;
 204                 max_buffer_size = config->pcm_hardware->buffer_bytes_max;
 205         } else {
 206                 prealloc_buffer_size = 512 * 1024;
 207                 max_buffer_size = SIZE_MAX;
 208         }
 209
 210
 211         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
 212                 substream = rtd->pcm->streams[i].substream;
 213                 if (!substream)
 214                         continue;
 215
 216                 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 217
 218                 if (!pcm->chan[i] &&
 219                     (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME))
 220                         pcm->chan[i] = dma_request_slave_channel(dev,
 221                                 dma_data->chan_name);
 222
 223                 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
 224                         pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
 225                                 substream);
 226                 }
 227
 228                 if (!pcm->chan[i]) {
 229                         dev_err(rtd->platform->dev,
 230                                 "Missing dma channel for stream: %d\n", i);
 231                         ret = -EINVAL;
 232                         goto err_free;
 233                 }
 234
 235                 ret = snd_pcm_lib_preallocate_pages(substream,
 236                                 SNDRV_DMA_TYPE_DEV_IRAM,
 237                                 dmaengine_dma_dev(pcm, substream),
 238                                 prealloc_buffer_size,
 239                                 max_buffer_size);
 240                 if (ret)
 241                         goto err_free;
 242         }
 243
 244         return 0;
 245
 246 err_free:
 247         dmaengine_pcm_free(rtd->pcm);
 248         return ret;
 249 }
 250
 251 static const struct snd_pcm_ops dmaengine_pcm_ops = {
 252         .open           = dmaengine_pcm_open,
 253         .close          = snd_dmaengine_pcm_close,
 254         .ioctl          = snd_pcm_lib_ioctl,
 255         .hw_params      = dmaengine_pcm_hw_params,
 256         .hw_free        = snd_pcm_lib_free_pages,
 257         .trigger        = snd_dmaengine_pcm_trigger,
 258         .pointer        = snd_dmaengine_pcm_pointer,
 259 };
 260
 261 static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
 262         .ops            = &dmaengine_pcm_ops,
 263         .pcm_new        = dmaengine_pcm_new,
 264         .pcm_free       = dmaengine_pcm_free,
 265         .probe_order    = SND_SOC_COMP_ORDER_LATE,
 266 };
 267
 268 static const struct snd_pcm_ops dmaengine_no_residue_pcm_ops = {
 269         .open           = dmaengine_pcm_open,
 270         .close          = snd_dmaengine_pcm_close,
 271         .ioctl          = snd_pcm_lib_ioctl,
 272         .hw_params      = dmaengine_pcm_hw_params,
 273         .hw_free        = snd_pcm_lib_free_pages,
 274         .trigger        = snd_dmaengine_pcm_trigger,
 275         .pointer        = snd_dmaengine_pcm_pointer_no_residue,
 276 };
 277
 278 static const struct snd_soc_platform_driver dmaengine_no_residue_pcm_platform = {
 279         .ops            = &dmaengine_no_residue_pcm_ops,
 280         .pcm_new        = dmaengine_pcm_new,
 281         .pcm_free       = dmaengine_pcm_free,
 282         .probe_order    = SND_SOC_COMP_ORDER_LATE,
 283 };
 284
 285 static const char * const dmaengine_pcm_dma_channel_names[] = {
 286         [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
 287         [SNDRV_PCM_STREAM_CAPTURE] = "rx",
 288 };
 289
 290 static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
 291         struct device *dev, const struct snd_dmaengine_pcm_config *config)
 292 {
 293         unsigned int i;
 294         const char *name;
 295         struct dma_chan *chan;
 296
 297         if ((pcm->flags & (SND_DMAENGINE_PCM_FLAG_NO_DT |
 298                            SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) ||
 299             !dev->of_node)
 300                 return 0;
 301
 302         if (config->dma_dev) {
 303                 /*
 304                  * If this warning is seen, it probably means that your Linux
 305                  * device structure does not match your HW device structure.
 306                  * It would be best to refactor the Linux device structure to
 307                  * correctly match the HW structure.
 308                  */
 309                 dev_warn(dev, "DMA channels sourced from device %s",
 310                          dev_name(config->dma_dev));
 311                 dev = config->dma_dev;
 312         }
 313
 314         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE;
 315              i++) {
 316                 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
 317                         name = "rx-tx";
 318                 else
 319                         name = dmaengine_pcm_dma_channel_names[i];
 320                 if (config->chan_names[i])
 321                         name = config->chan_names[i];
 322                 chan = dma_request_slave_channel_reason(dev, name);
 323                 if (IS_ERR(chan)) {
 324                         if (PTR_ERR(chan) == -EPROBE_DEFER)
 325                                 return -EPROBE_DEFER;
 326                         pcm->chan[i] = NULL;
 327                 } else {
 328                         pcm->chan[i] = chan;
 329                 }
 330                 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
 331                         break;
 332         }
 333
 334         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
 335                 pcm->chan[1] = pcm->chan[0];
 336
 337         return 0;
 338 }
 339
 340 static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm)
 341 {
 342         unsigned int i;
 343
 344         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE;
 345              i++) {
 346                 if (!pcm->chan[i])
 347                         continue;
 348                 dma_release_channel(pcm->chan[i]);
 349                 if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
 350                         break;
 351         }
 352 }
 353
 354 /**
 355  * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
 356  * @dev: The parent device for the PCM device
 357  * @config: Platform specific PCM configuration
 358  * @flags: Platform specific quirks
 359  */
 360 int snd_dmaengine_pcm_register(struct device *dev,
 361         const struct snd_dmaengine_pcm_config *config, unsigned int flags)
 362 {
 363         struct dmaengine_pcm *pcm;
 364         int ret;
 365
 366         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 367         if (!pcm)
 368                 return -ENOMEM;
 369
 370         pcm->config = config;
 371         pcm->flags = flags;
 372
 373         ret = dmaengine_pcm_request_chan_of(pcm, dev, config);
 374         if (ret)
 375                 goto err_free_dma;
 376
 377         if (flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
 378                 ret = snd_soc_add_platform(dev, &pcm->platform,
 379                                 &dmaengine_no_residue_pcm_platform);
 380         else
 381                 ret = snd_soc_add_platform(dev, &pcm->platform,
 382                                 &dmaengine_pcm_platform);
 383         if (ret)
 384                 goto err_free_dma;
 385
 386         return 0;
 387
 388 err_free_dma:
 389         dmaengine_pcm_release_chan(pcm);
 390         kfree(pcm);
 391         return ret;
 392 }
 393 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
 394
 395 /**
 396  * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
 397  * @dev: Parent device the PCM was register with
 398  *
 399  * Removes a dmaengine based PCM device previously registered with
 400  * snd_dmaengine_pcm_register.
 401  */
 402 void snd_dmaengine_pcm_unregister(struct device *dev)
 403 {
 404         struct snd_soc_platform *platform;
 405         struct dmaengine_pcm *pcm;
 406
 407         platform = snd_soc_lookup_platform(dev);
 408         if (!platform)
 409                 return;
 410
 411         pcm = soc_platform_to_pcm(platform);
 412
 413         snd_soc_remove_platform(platform);
 414         dmaengine_pcm_release_chan(pcm);
 415         kfree(pcm);
 416 }
 417 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
 418
 419 MODULE_LICENSE("GPL");