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

   1 /*
   2  * imx-pcm-dma-mx2.c  --  ALSA Soc Audio Layer
   3  *
   4  * Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
   5  *
   6  * This code is based on code copyrighted by Freescale,
   7  * Liam Girdwood, Javier Martin and probably others.
   8  *
   9  *  This program is free software; you can redistribute  it and/or modify it
  10  *  under  the terms of  the GNU General  Public License as published by the
  11  *  Free Software Foundation;  either version 2 of the  License, or (at your
  12  *  option) any later version.
  13  */
  14 #include <linux/platform_device.h>
  15 #include <linux/dmaengine.h>
  16 #include <linux/types.h>
  17 #include <linux/module.h>
  18
  19 #include <sound/core.h>
  20 #include <sound/pcm.h>
  21 #include <sound/soc.h>
  22 #include <sound/dmaengine_pcm.h>
  23
  24 #include "imx-pcm.h"
  25
  26 static bool filter(struct dma_chan *chan, void *param)
  27 {
  28         if (!imx_dma_is_general_purpose(chan))
  29                 return false;
  30
  31         chan->private = param;
  32
  33         return true;
  34 }
  35
  36 static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = {
  37         .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
  38         .compat_filter_fn = filter,
  39 };
  40
  41 int imx_pcm_dma_init(struct platform_device *pdev, size_t size)
  42 {
  43         struct snd_dmaengine_pcm_config *config;
  44
  45         config = devm_kzalloc(&pdev->dev,
  46                         sizeof(struct snd_dmaengine_pcm_config), GFP_KERNEL);
  47         if (!config)
  48                 return -ENOMEM;
  49         *config = imx_dmaengine_pcm_config;
  50
  51         return devm_snd_dmaengine_pcm_register(&pdev->dev,
  52                 config,
  53                 SND_DMAENGINE_PCM_FLAG_COMPAT);
  54 }
  55 EXPORT_SYMBOL_GPL(imx_pcm_dma_init);
  56
  57 MODULE_LICENSE("GPL");