sound/soc/soc-dmaengine-pcm.c

   1 /*
   2  *  Copyright (C) 2012, Analog Devices Inc.
   3  *      Author: Lars-Peter Clausen <lars@metafoo.de>
   4  *
   5  *  Based on:
   6  *      imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
   7  *      mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
   8  *      ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
   9  *                    Copyright (C) 2006 Applied Data Systems
  10  *
  11  *  This program is free software; you can redistribute it and/or modify it
  12  *  under  the terms of the GNU General  Public License as published by the
  13  *  Free Software Foundation;  either version 2 of the License, or (at your
  14  *  option) any later version.
  15  *
  16  *  You should have received a copy of the GNU General Public License along
  17  *  with this program; if not, write to the Free Software Foundation, Inc.,
  18  *  675 Mass Ave, Cambridge, MA 02139, USA.
  19  *
  20  */
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/dmaengine.h>
  24 #include <linux/slab.h>
  25 #include <sound/pcm.h>
  26 #include <sound/pcm_params.h>
  27 #include <sound/soc.h>
  28
  29 #include <sound/dmaengine_pcm.h>
  30
  31 struct dmaengine_pcm_runtime_data {
  32         struct dma_chan *dma_chan;
  33         dma_cookie_t cookie;
  34
  35         unsigned int pos;
  36 };
  37
  38 static inline struct dmaengine_pcm_runtime_data *substream_to_prtd(
  39         const struct snd_pcm_substream *substream)
  40 {
  41         return substream->runtime->private_data;
  42 }
  43
  44 struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream)
  45 {
  46         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
  47
  48         return prtd->dma_chan;
  49 }
  50 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan);
  51
  52 /**
  53  * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config
  54  * @substream: PCM substream
  55  * @params: hw_params
  56  * @slave_config: DMA slave config
  57  *
  58  * This function can be used to initialize a dma_slave_config from a substream
  59  * and hw_params in a dmaengine based PCM driver implementation.
  60  */
  61 int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
  62         const struct snd_pcm_hw_params *params,
  63         struct dma_slave_config *slave_config)
  64 {
  65         enum dma_slave_buswidth buswidth;
  66
  67         switch (params_format(params)) {
  68         case SNDRV_PCM_FORMAT_S8:
  69                 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
  70                 break;
  71         case SNDRV_PCM_FORMAT_S16_LE:
  72                 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
  73                 break;
  74         case SNDRV_PCM_FORMAT_S18_3LE:
  75         case SNDRV_PCM_FORMAT_S20_3LE:
  76         case SNDRV_PCM_FORMAT_S24_LE:
  77         case SNDRV_PCM_FORMAT_S32_LE:
  78                 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
  79                 break;
  80         default:
  81                 return -EINVAL;
  82         }
  83
  84         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  85                 slave_config->direction = DMA_MEM_TO_DEV;
  86                 slave_config->dst_addr_width = buswidth;
  87         } else {
  88                 slave_config->direction = DMA_DEV_TO_MEM;
  89                 slave_config->src_addr_width = buswidth;
  90         }
  91
  92         slave_config->device_fc = false;
  93
  94         return 0;
  95 }
  96 EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);
  97
  98 /**
  99  * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config
 100  *  using DAI DMA data.
 101  * @substream: PCM substream
 102  * @dma_data: DAI DMA data
 103  * @slave_config: DMA slave configuration
 104  *
 105  * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width and
 106  * slave_id fields of the DMA slave config from the same fields of the DAI DMA
 107  * data struct. The src and dst fields will be initialized depending on the
 108  * direction of the substream. If the substream is a playback stream the dst
 109  * fields will be initialized, if it is a capture stream the src fields will be
 110  * initialized. The {dst,src}_addr_width field will only be initialized if the
 111  * addr_width field of the DAI DMA data struct is not equal to
 112  * DMA_SLAVE_BUSWIDTH_UNDEFINED.
 113  */
 114 void snd_dmaengine_pcm_set_config_from_dai_data(
 115         const struct snd_pcm_substream *substream,
 116         const struct snd_dmaengine_dai_dma_data *dma_data,
 117         struct dma_slave_config *slave_config)
 118 {
 119         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 120                 slave_config->dst_addr = dma_data->addr;
 121                 slave_config->dst_maxburst = dma_data->maxburst;
 122                 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
 123                         slave_config->dst_addr_width = dma_data->addr_width;
 124         } else {
 125                 slave_config->src_addr = dma_data->addr;
 126                 slave_config->src_maxburst = dma_data->maxburst;
 127                 if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
 128                         slave_config->src_addr_width = dma_data->addr_width;
 129         }
 130
 131         slave_config->slave_id = dma_data->slave_id;
 132 }
 133 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);
 134
 135 static void dmaengine_pcm_dma_complete(void *arg)
 136 {
 137         struct snd_pcm_substream *substream = arg;
 138         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 139
 140         prtd->pos += snd_pcm_lib_period_bytes(substream);
 141         if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream))
 142                 prtd->pos = 0;
 143
 144         snd_pcm_period_elapsed(substream);
 145 }
 146
 147 static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
 148 {
 149         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 150         struct dma_chan *chan = prtd->dma_chan;
 151         struct dma_async_tx_descriptor *desc;
 152         enum dma_transfer_direction direction;
 153         unsigned long flags = DMA_CTRL_ACK;
 154
 155         direction = snd_pcm_substream_to_dma_direction(substream);
 156
 157         if (!substream->runtime->no_period_wakeup)
 158                 flags |= DMA_PREP_INTERRUPT;
 159
 160         prtd->pos = 0;
 161         desc = dmaengine_prep_dma_cyclic(chan,
 162                 substream->runtime->dma_addr,
 163                 snd_pcm_lib_buffer_bytes(substream),
 164                 snd_pcm_lib_period_bytes(substream), direction, flags);
 165
 166         if (!desc)
 167                 return -ENOMEM;
 168
 169         desc->callback = dmaengine_pcm_dma_complete;
 170         desc->callback_param = substream;
 171         prtd->cookie = dmaengine_submit(desc);
 172
 173         return 0;
 174 }
 175
 176 /**
 177  * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation
 178  * @substream: PCM substream
 179  * @cmd: Trigger command
 180  *
 181  * Returns 0 on success, a negative error code otherwise.
 182  *
 183  * This function can be used as the PCM trigger callback for dmaengine based PCM
 184  * driver implementations.
 185  */
 186 int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 187 {
 188         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 189         int ret;
 190
 191         switch (cmd) {
 192         case SNDRV_PCM_TRIGGER_START:
 193                 ret = dmaengine_pcm_prepare_and_submit(substream);
 194                 if (ret)
 195                         return ret;
 196                 dma_async_issue_pending(prtd->dma_chan);
 197                 break;
 198         case SNDRV_PCM_TRIGGER_RESUME:
 199         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 200                 dmaengine_resume(prtd->dma_chan);
 201                 break;
 202         case SNDRV_PCM_TRIGGER_SUSPEND:
 203         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 204                 dmaengine_pause(prtd->dma_chan);
 205                 break;
 206         case SNDRV_PCM_TRIGGER_STOP:
 207                 dmaengine_terminate_all(prtd->dma_chan);
 208                 break;
 209         default:
 210                 return -EINVAL;
 211         }
 212
 213         return 0;
 214 }
 215 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);
 216
 217 /**
 218  * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation
 219  * @substream: PCM substream
 220  *
 221  * This function is deprecated and should not be used by new drivers, as its
 222  * results may be unreliable.
 223  */
 224 snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)
 225 {
 226         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 227         return bytes_to_frames(substream->runtime, prtd->pos);
 228 }
 229 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);
 230
 231 /**
 232  * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation
 233  * @substream: PCM substream
 234  *
 235  * This function can be used as the PCM pointer callback for dmaengine based PCM
 236  * driver implementations.
 237  */
 238 snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
 239 {
 240         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 241         struct dma_tx_state state;
 242         enum dma_status status;
 243         unsigned int buf_size;
 244         unsigned int pos = 0;
 245
 246         status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
 247         if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
 248                 buf_size = snd_pcm_lib_buffer_bytes(substream);
 249                 if (state.residue > 0 && state.residue <= buf_size)
 250                         pos = buf_size - state.residue;
 251         }
 252
 253         return bytes_to_frames(substream->runtime, pos);
 254 }
 255 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
 256
 257 /**
 258  * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
 259  * @filter_fn: Filter function used to request the DMA channel
 260  * @filter_data: Data passed to the DMA filter function
 261  *
 262  * Returns NULL or the requested DMA channel.
 263  *
 264  * This function request a DMA channel for usage with dmaengine PCM.
 265  */
 266 struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
 267         void *filter_data)
 268 {
 269         dma_cap_mask_t mask;
 270
 271         dma_cap_zero(mask);
 272         dma_cap_set(DMA_SLAVE, mask);
 273         dma_cap_set(DMA_CYCLIC, mask);
 274
 275         return dma_request_channel(mask, filter_fn, filter_data);
 276 }
 277 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
 278
 279 /**
 280  * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
 281  * @substream: PCM substream
 282  * @chan: DMA channel to use for data transfers
 283  *
 284  * Returns 0 on success, a negative error code otherwise.
 285  *
 286  * The function should usually be called from the pcm open callback. Note that
 287  * this function will use private_data field of the substream's runtime. So it
 288  * is not availabe to your pcm driver implementation.
 289  */
 290 int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
 291         struct dma_chan *chan)
 292 {
 293         struct dmaengine_pcm_runtime_data *prtd;
 294         int ret;
 295
 296         if (!chan)
 297                 return -ENXIO;
 298
 299         ret = snd_pcm_hw_constraint_integer(substream->runtime,
 300                                             SNDRV_PCM_HW_PARAM_PERIODS);
 301         if (ret < 0)
 302                 return ret;
 303
 304         prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
 305         if (!prtd)
 306                 return -ENOMEM;
 307
 308         prtd->dma_chan = chan;
 309
 310         substream->runtime->private_data = prtd;
 311
 312         return 0;
 313 }
 314 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);
 315
 316 /**
 317  * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel
 318  * @substream: PCM substream
 319  * @filter_fn: Filter function used to request the DMA channel
 320  * @filter_data: Data passed to the DMA filter function
 321  *
 322  * Returns 0 on success, a negative error code otherwise.
 323  *
 324  * This function will request a DMA channel using the passed filter function and
 325  * data. The function should usually be called from the pcm open callback. Note
 326  * that this function will use private_data field of the substream's runtime. So
 327  * it is not availabe to your pcm driver implementation.
 328  */
 329 int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
 330         dma_filter_fn filter_fn, void *filter_data)
 331 {
 332         return snd_dmaengine_pcm_open(substream,
 333                     snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
 334 }
 335 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
 336
 337 /**
 338  * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream
 339  * @substream: PCM substream
 340  */
 341 int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
 342 {
 343         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 344
 345         kfree(prtd);
 346
 347         return 0;
 348 }
 349 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
 350
 351 /**
 352  * snd_dmaengine_pcm_release_chan_close - Close a dmaengine based PCM substream and release channel
 353  * @substream: PCM substream
 354  *
 355  * Releases the DMA channel associated with the PCM substream.
 356  */
 357 int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
 358 {
 359         struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
 360
 361         dma_release_channel(prtd->dma_chan);
 362
 363         return snd_dmaengine_pcm_close(substream);
 364 }
 365 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
 366
 367 MODULE_LICENSE("GPL");