LXR linux/sound/soc/ti/sdma-pcm.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com
   4 *  Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
   5 */
   6
   7#include <linux/device.h>
   8#include <linux/module.h>
   9#include <sound/core.h>
  10#include <sound/pcm.h>
  11#include <sound/pcm_params.h>
  12#include <sound/soc.h>
  13#include <sound/dmaengine_pcm.h>
  14
  15#include "sdma-pcm.h"
  16
  17static const struct snd_pcm_hardware sdma_pcm_hardware = {
  18        .info                   = SNDRV_PCM_INFO_MMAP |
  19                                  SNDRV_PCM_INFO_MMAP_VALID |
  20                                  SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME |
  21                                  SNDRV_PCM_INFO_NO_PERIOD_WAKEUP |
  22                                  SNDRV_PCM_INFO_INTERLEAVED,
  23        .period_bytes_min       = 32,
  24        .period_bytes_max       = 64 * 1024,
  25        .buffer_bytes_max       = 128 * 1024,
  26        .periods_min            = 2,
  27        .periods_max            = 255,
  28};
  29
  30static const struct snd_dmaengine_pcm_config sdma_dmaengine_pcm_config = {
  31        .pcm_hardware = &sdma_pcm_hardware,
  32        .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
  33        .prealloc_buffer_size = 128 * 1024,
  34};
  35
  36int sdma_pcm_platform_register(struct device *dev,
  37                               char *txdmachan, char *rxdmachan)
  38{
  39        struct snd_dmaengine_pcm_config *config;
  40        unsigned int flags = 0;
  41
  42        /* Standard names for the directions: 'tx' and 'rx' */
  43        if (!txdmachan && !rxdmachan)
  44                return devm_snd_dmaengine_pcm_register(dev,
  45                                                &sdma_dmaengine_pcm_config, 0);
  46
  47        config = devm_kzalloc(dev, sizeof(*config), GFP_KERNEL);
  48        if (!config)
  49                return -ENOMEM;
  50
  51        *config = sdma_dmaengine_pcm_config;
  52
  53        if (!txdmachan || !rxdmachan) {
  54                /* One direction only PCM */
  55                flags |= SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX;
  56                if (!txdmachan) {
  57                        txdmachan = rxdmachan;
  58                        rxdmachan = NULL;
  59                }
  60        }
  61
  62        config->chan_names[0] = txdmachan;
  63        config->chan_names[1] = rxdmachan;
  64
  65        return devm_snd_dmaengine_pcm_register(dev, config, flags);
  66}
  67EXPORT_SYMBOL_GPL(sdma_pcm_platform_register);
  68
  69MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
  70MODULE_DESCRIPTION("sDMA PCM ASoC platform driver");
  71MODULE_LICENSE("GPL v2");
  72