LXR linux/sound/soc/soc-utils.c

   1/*
   2 * soc-util.c  --  ALSA SoC Audio Layer utility functions
   3 *
   4 * Copyright 2009 Wolfson Microelectronics PLC.
   5 *
   6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7 *         Liam Girdwood <lrg@slimlogic.co.uk>
   8 *         
   9 *
  10 *  This program is free software; you can redistribute  it and/or modify it
  11 *  under  the terms of  the GNU General  Public License as published by the
  12 *  Free Software Foundation;  either version 2 of the  License, or (at your
  13 *  option) any later version.
  14 */
  15
  16#include <linux/platform_device.h>
  17#include <linux/export.h>
  18#include <sound/core.h>
  19#include <sound/pcm.h>
  20#include <sound/pcm_params.h>
  21#include <sound/soc.h>
  22
  23int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots)
  24{
  25        return sample_size * channels * tdm_slots;
  26}
  27EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size);
  28
  29int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params)
  30{
  31        int sample_size;
  32
  33        sample_size = snd_pcm_format_width(params_format(params));
  34        if (sample_size < 0)
  35                return sample_size;
  36
  37        return snd_soc_calc_frame_size(sample_size, params_channels(params),
  38                                       1);
  39}
  40EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size);
  41
  42int snd_soc_calc_bclk(int fs, int sample_size, int channels, int tdm_slots)
  43{
  44        return fs * snd_soc_calc_frame_size(sample_size, channels, tdm_slots);
  45}
  46EXPORT_SYMBOL_GPL(snd_soc_calc_bclk);
  47
  48int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params)
  49{
  50        int ret;
  51
  52        ret = snd_soc_params_to_frame_size(params);
  53
  54        if (ret > 0)
  55                return ret * params_rate(params);
  56        else
  57                return ret;
  58}
  59EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk);
  60
  61static const struct snd_pcm_hardware dummy_dma_hardware = {
  62        .formats                = 0xffffffff,
  63        .channels_min           = 1,
  64        .channels_max           = UINT_MAX,
  65
  66        /* Random values to keep userspace happy when checking constraints */
  67        .info                   = SNDRV_PCM_INFO_INTERLEAVED |
  68                                  SNDRV_PCM_INFO_BLOCK_TRANSFER,
  69        .buffer_bytes_max       = 128*1024,
  70        .period_bytes_min       = PAGE_SIZE,
  71        .period_bytes_max       = PAGE_SIZE*2,
  72        .periods_min            = 2,
  73        .periods_max            = 128,
  74};
  75
  76static int dummy_dma_open(struct snd_pcm_substream *substream)
  77{
  78        snd_soc_set_runtime_hwparams(substream, &dummy_dma_hardware);
  79
  80        return 0;
  81}
  82
  83static struct snd_pcm_ops dummy_dma_ops = {
  84        .open           = dummy_dma_open,
  85        .ioctl          = snd_pcm_lib_ioctl,
  86};
  87
  88static struct snd_soc_platform_driver dummy_platform = {
  89        .ops = &dummy_dma_ops,
  90};
  91
  92static struct snd_soc_codec_driver dummy_codec;
  93static struct snd_soc_dai_driver dummy_dai = {
  94        .name = "snd-soc-dummy-dai",
  95};
  96
  97static int snd_soc_dummy_probe(struct platform_device *pdev)
  98{
  99        int ret;
 100
 101        ret = snd_soc_register_codec(&pdev->dev, &dummy_codec, &dummy_dai, 1);
 102        if (ret < 0)
 103                return ret;
 104
 105        ret = snd_soc_register_platform(&pdev->dev, &dummy_platform);
 106        if (ret < 0) {
 107                snd_soc_unregister_codec(&pdev->dev);
 108                return ret;
 109        }
 110
 111        return ret;
 112}
 113
 114static int snd_soc_dummy_remove(struct platform_device *pdev)
 115{
 116        snd_soc_unregister_platform(&pdev->dev);
 117        snd_soc_unregister_codec(&pdev->dev);
 118
 119        return 0;
 120}
 121
 122static struct platform_driver soc_dummy_driver = {
 123        .driver = {
 124                .name = "snd-soc-dummy",
 125                .owner = THIS_MODULE,
 126        },
 127        .probe = snd_soc_dummy_probe,
 128        .remove = snd_soc_dummy_remove,
 129};
 130
 131static struct platform_device *soc_dummy_dev;
 132
 133int __init snd_soc_util_init(void)
 134{
 135        int ret;
 136
 137        soc_dummy_dev = platform_device_alloc("snd-soc-dummy", -1);
 138        if (!soc_dummy_dev)
 139                return -ENOMEM;
 140
 141        ret = platform_device_add(soc_dummy_dev);
 142        if (ret != 0) {
 143                platform_device_put(soc_dummy_dev);
 144                return ret;
 145        }
 146
 147        ret = platform_driver_register(&soc_dummy_driver);
 148        if (ret != 0)
 149                platform_device_unregister(soc_dummy_dev);
 150
 151        return ret;
 152}
 153
 154void __exit snd_soc_util_exit(void)
 155{
 156        platform_device_unregister(soc_dummy_dev);
 157        platform_driver_unregister(&soc_dummy_driver);
 158}
 159