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_CAPTURE + 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         if (!pcm->config)
  94                 prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
  95         else
  96                 prepare_slave_config = pcm->config->prepare_slave_config;
  97
  98         if (prepare_slave_config) {
  99                 ret = prepare_slave_config(substream, params, &slave_config);
 100                 if (ret)
 101                         return ret;
 102
 103                 ret = dmaengine_slave_config(chan, &slave_config);
 104                 if (ret)
 105                         return ret;
 106         }
 107
 108         return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
 109 }
 110
 111 static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream)
 112 {
 113         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 114         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 115         struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
 116         struct dma_chan *chan = pcm->chan[substream->stream];
 117         struct snd_dmaengine_dai_dma_data *dma_data;
 118         struct dma_slave_caps dma_caps;
 119         struct snd_pcm_hardware hw;
 120         int ret;
 121
 122         if (pcm->config && pcm->config->pcm_hardware)
 123                 return snd_soc_set_runtime_hwparams(substream,
 124                                 pcm->config->pcm_hardware);
 125
 126         dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 127
 128         memset(&hw, 0, sizeof(hw));
 129         hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 130                         SNDRV_PCM_INFO_INTERLEAVED;
 131         hw.periods_min = 2;
 132         hw.periods_max = UINT_MAX;
 133         hw.period_bytes_min = 256;
 134         hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
 135         hw.buffer_bytes_max = SIZE_MAX;
 136         hw.fifo_size = dma_data->fifo_size;
 137
 138         ret = dma_get_slave_caps(chan, &dma_caps);
 139         if (ret == 0) {
 140                 if (dma_caps.cmd_pause)
 141                         hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
 142         }
 143
 144         return snd_soc_set_runtime_hwparams(substream, &hw);
 145 }
 146
 147 static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
 148 {
 149         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 150         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 151         struct dma_chan *chan = pcm->chan[substream->stream];
 152         int ret;
 153
 154         ret = dmaengine_pcm_set_runtime_hwparams(substream);
 155         if (ret)
 156                 return ret;
 157
 158         return snd_dmaengine_pcm_open(substream, chan);
 159 }
 160
 161 static void dmaengine_pcm_free(struct snd_pcm *pcm)
 162 {
 163         snd_pcm_lib_preallocate_free_for_all(pcm);
 164 }
 165
 166 static struct dma_chan *dmaengine_pcm_compat_request_channel(
 167         struct snd_soc_pcm_runtime *rtd,
 168         struct snd_pcm_substream *substream)
 169 {
 170         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 171
 172         if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
 173                 return pcm->chan[0];
 174
 175         if (pcm->config->compat_request_channel)
 176                 return pcm->config->compat_request_channel(rtd, substream);
 177
 178         return snd_dmaengine_pcm_request_channel(pcm->config->compat_filter_fn,
 179                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream));
 180 }
 181
 182 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
 183 {
 184         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 185         const struct snd_dmaengine_pcm_config *config = pcm->config;
 186         struct snd_pcm_substream *substream;
 187         size_t prealloc_buffer_size;
 188         size_t max_buffer_size;
 189         unsigned int i;
 190         int ret;
 191
 192         if (config && config->prealloc_buffer_size) {
 193                 prealloc_buffer_size = config->prealloc_buffer_size;
 194                 max_buffer_size = config->pcm_hardware->buffer_bytes_max;
 195         } else {
 196                 prealloc_buffer_size = 512 * 1024;
 197                 max_buffer_size = SIZE_MAX;
 198         }
 199
 200
 201         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
 202                 substream = rtd->pcm->streams[i].substream;
 203                 if (!substream)
 204                         continue;
 205
 206                 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
 207                         pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
 208                                 substream);
 209                 }
 210
 211                 if (!pcm->chan[i]) {
 212                         dev_err(rtd->platform->dev,
 213                                 "Missing dma channel for stream: %d\n", i);
 214                         ret = -EINVAL;
 215                         goto err_free;
 216                 }
 217
 218                 ret = snd_pcm_lib_preallocate_pages(substream,
 219                                 SNDRV_DMA_TYPE_DEV,
 220                                 dmaengine_dma_dev(pcm, substream),
 221                                 prealloc_buffer_size,
 222                                 max_buffer_size);
 223                 if (ret)
 224                         goto err_free;
 225         }
 226
 227         return 0;
 228
 229 err_free:
 230         dmaengine_pcm_free(rtd->pcm);
 231         return ret;
 232 }
 233
 234 static const struct snd_pcm_ops dmaengine_pcm_ops = {
 235         .open           = dmaengine_pcm_open,
 236         .close          = snd_dmaengine_pcm_close,
 237         .ioctl          = snd_pcm_lib_ioctl,
 238         .hw_params      = dmaengine_pcm_hw_params,
 239         .hw_free        = snd_pcm_lib_free_pages,
 240         .trigger        = snd_dmaengine_pcm_trigger,
 241         .pointer        = snd_dmaengine_pcm_pointer,
 242 };
 243
 244 static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
 245         .ops            = &dmaengine_pcm_ops,
 246         .pcm_new        = dmaengine_pcm_new,
 247         .pcm_free       = dmaengine_pcm_free,
 248         .probe_order    = SND_SOC_COMP_ORDER_LATE,
 249 };
 250
 251 static const struct snd_pcm_ops dmaengine_no_residue_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_no_residue,
 259 };
 260
 261 static const struct snd_soc_platform_driver dmaengine_no_residue_pcm_platform = {
 262         .ops            = &dmaengine_no_residue_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 char * const dmaengine_pcm_dma_channel_names[] = {
 269         [SNDRV_PCM_STREAM_PLAYBACK] = "tx",
 270         [SNDRV_PCM_STREAM_CAPTURE] = "rx",
 271 };
 272
 273 static void dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
 274         struct device *dev)
 275 {
 276         unsigned int i;
 277
 278         if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || !dev->of_node)
 279                 return;
 280
 281         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) {
 282                 pcm->chan[0] = dma_request_slave_channel(dev, "rx-tx");
 283                 pcm->chan[1] = pcm->chan[0];
 284         } else {
 285                 for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
 286                         pcm->chan[i] = dma_request_slave_channel(dev,
 287                                         dmaengine_pcm_dma_channel_names[i]);
 288                 }
 289         }
 290 }
 291
 292 /**
 293  * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
 294  * @dev: The parent device for the PCM device
 295  * @config: Platform specific PCM configuration
 296  * @flags: Platform specific quirks
 297  */
 298 int snd_dmaengine_pcm_register(struct device *dev,
 299         const struct snd_dmaengine_pcm_config *config, unsigned int flags)
 300 {
 301         struct dmaengine_pcm *pcm;
 302
 303         pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
 304         if (!pcm)
 305                 return -ENOMEM;
 306
 307         pcm->config = config;
 308         pcm->flags = flags;
 309
 310         dmaengine_pcm_request_chan_of(pcm, dev);
 311
 312         if (flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
 313                 return snd_soc_add_platform(dev, &pcm->platform,
 314                                 &dmaengine_no_residue_pcm_platform);
 315         else
 316                 return snd_soc_add_platform(dev, &pcm->platform,
 317                                 &dmaengine_pcm_platform);
 318 }
 319 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
 320
 321 /**
 322  * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
 323  * @dev: Parent device the PCM was register with
 324  *
 325  * Removes a dmaengine based PCM device previously registered with
 326  * snd_dmaengine_pcm_register.
 327  */
 328 void snd_dmaengine_pcm_unregister(struct device *dev)
 329 {
 330         struct snd_soc_platform *platform;
 331         struct dmaengine_pcm *pcm;
 332         unsigned int i;
 333
 334         platform = snd_soc_lookup_platform(dev);
 335         if (!platform)
 336                 return;
 337
 338         pcm = soc_platform_to_pcm(platform);
 339
 340         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
 341                 if (pcm->chan[i]) {
 342                         dma_release_channel(pcm->chan[i]);
 343                         if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
 344                                 break;
 345                 }
 346         }
 347
 348         snd_soc_remove_platform(platform);
 349         kfree(pcm);
 350 }
 351 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
 352
 353 MODULE_LICENSE("GPL");