root/sound/soc/fsl/imx-pcm-dma.c

DEFINITIONS

1. filter
2. imx_pcm_dma_init

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * imx-pcm-dma-mx2.c  --  ALSA Soc Audio Layer
   4  *
   5  * Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
   6  *
   7  * This code is based on code copyrighted by Freescale,
   8  * Liam Girdwood, Javier Martin and probably others.
   9  */
  10 #include <linux/platform_device.h>
  11 #include <linux/dmaengine.h>
  12 #include <linux/types.h>
  13 #include <linux/module.h>
  14 
  15 #include <sound/core.h>
  16 #include <sound/pcm.h>
  17 #include <sound/soc.h>
  18 #include <sound/dmaengine_pcm.h>
  19 
  20 #include "imx-pcm.h"
  21 
  22 static bool filter(struct dma_chan *chan, void *param)
  23 {
  24         if (!imx_dma_is_general_purpose(chan))
  25                 return false;
  26 
  27         chan->private = param;
  28 
  29         return true;
  30 }
  31 
  32 static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = {
  33         .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
  34         .compat_filter_fn = filter,
  35 };
  36 
  37 int imx_pcm_dma_init(struct platform_device *pdev, size_t size)
  38 {
  39         struct snd_dmaengine_pcm_config *config;
  40 
  41         config = devm_kzalloc(&pdev->dev,
  42                         sizeof(struct snd_dmaengine_pcm_config), GFP_KERNEL);
  43         if (!config)
  44                 return -ENOMEM;
  45         *config = imx_dmaengine_pcm_config;
  46 
  47         return devm_snd_dmaengine_pcm_register(&pdev->dev,
  48                 config,
  49                 SND_DMAENGINE_PCM_FLAG_COMPAT);
  50 }
  51 EXPORT_SYMBOL_GPL(imx_pcm_dma_init);
  52 
  53 MODULE_LICENSE("GPL");