root/sound/soc/ti/sdma-pcm.c

DEFINITIONS

1. sdma_pcm_platform_register

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 2018 Texas Instruments Incorporated - http://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 
  17 static 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 
  30 static 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 
  36 int 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 }
  67 EXPORT_SYMBOL_GPL(sdma_pcm_platform_register);
  68 
  69 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
  70 MODULE_DESCRIPTION("sDMA PCM ASoC platform driver");
  71 MODULE_LICENSE("GPL v2");