kernel/sound/soc/cirrus/ep93xx-pcm.c

   1 /*
   2  * linux/sound/arm/ep93xx-pcm.c - EP93xx ALSA PCM interface
   3  *
   4  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
   5  * Copyright (C) 2006 Applied Data Systems
   6  *
   7  * Rewritten for the SoC audio subsystem (Based on PXA2xx code):
   8  *   Copyright (c) 2008 Ryan Mallon
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/dmaengine.h>
  19
  20 #include <sound/pcm.h>
  21 #include <sound/soc.h>
  22 #include <sound/dmaengine_pcm.h>
  23
  24 #include <linux/platform_data/dma-ep93xx.h>
  25
  26 #include "ep93xx-pcm.h"
  27
  28 static const struct snd_pcm_hardware ep93xx_pcm_hardware = {
  29         .info                   = (SNDRV_PCM_INFO_MMAP          |
  30                                    SNDRV_PCM_INFO_MMAP_VALID    |
  31                                    SNDRV_PCM_INFO_INTERLEAVED   |
  32                                    SNDRV_PCM_INFO_BLOCK_TRANSFER),
  33         .buffer_bytes_max       = 131072,
  34         .period_bytes_min       = 32,
  35         .period_bytes_max       = 32768,
  36         .periods_min            = 1,
  37         .periods_max            = 32,
  38         .fifo_size              = 32,
  39 };
  40
  41 static bool ep93xx_pcm_dma_filter(struct dma_chan *chan, void *filter_param)
  42 {
  43         struct ep93xx_dma_data *data = filter_param;
  44
  45         if (data->direction == ep93xx_dma_chan_direction(chan)) {
  46                 chan->private = data;
  47                 return true;
  48         }
  49
  50         return false;
  51 }
  52
  53 static const struct snd_dmaengine_pcm_config ep93xx_dmaengine_pcm_config = {
  54         .pcm_hardware = &ep93xx_pcm_hardware,
  55         .compat_filter_fn = ep93xx_pcm_dma_filter,
  56         .prealloc_buffer_size = 131072,
  57 };
  58
  59 int devm_ep93xx_pcm_platform_register(struct device *dev)
  60 {
  61         return devm_snd_dmaengine_pcm_register(dev,
  62                 &ep93xx_dmaengine_pcm_config,
  63                 SND_DMAENGINE_PCM_FLAG_NO_RESIDUE |
  64                 SND_DMAENGINE_PCM_FLAG_NO_DT |
  65                 SND_DMAENGINE_PCM_FLAG_COMPAT);
  66 }
  67 EXPORT_SYMBOL_GPL(devm_ep93xx_pcm_platform_register);
  68
  69 MODULE_AUTHOR("Ryan Mallon");
  70 MODULE_DESCRIPTION("EP93xx ALSA PCM interface");
  71 MODULE_LICENSE("GPL");