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 <sound/core.h>
  18 #include <sound/pcm.h>
  19 #include <sound/pcm_params.h>
  20 #include <sound/soc.h>
  21
  22 int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots)
  23 {
  24         return sample_size * channels * tdm_slots;
  25 }
  26 EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size);
  27
  28 int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params)
  29 {
  30         int sample_size;
  31
  32         sample_size = snd_pcm_format_width(params_format(params));
  33         if (sample_size < 0)
  34                 return sample_size;
  35
  36         return snd_soc_calc_frame_size(sample_size, params_channels(params),
  37                                        1);
  38 }
  39 EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size);
  40
  41 int snd_soc_calc_bclk(int fs, int sample_size, int channels, int tdm_slots)
  42 {
  43         return fs * snd_soc_calc_frame_size(sample_size, channels, tdm_slots);
  44 }
  45 EXPORT_SYMBOL_GPL(snd_soc_calc_bclk);
  46
  47 int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params)
  48 {
  49         int ret;
  50
  51         ret = snd_soc_params_to_frame_size(params);
  52
  53         if (ret > 0)
  54                 return ret * params_rate(params);
  55         else
  56                 return ret;
  57 }
  58 EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk);
  59
  60 static const struct snd_pcm_hardware dummy_dma_hardware = {
  61         .formats                = 0xffffffff,
  62         .channels_min           = 1,
  63         .channels_max           = UINT_MAX,
  64
  65         /* Random values to keep userspace happy when checking constraints */
  66         .info                   = SNDRV_PCM_INFO_INTERLEAVED |
  67                                   SNDRV_PCM_INFO_BLOCK_TRANSFER,
  68         .buffer_bytes_max       = 128*1024,
  69         .period_bytes_min       = PAGE_SIZE,
  70         .period_bytes_max       = PAGE_SIZE*2,
  71         .periods_min            = 2,
  72         .periods_max            = 128,
  73 };
  74
  75 static int dummy_dma_open(struct snd_pcm_substream *substream)
  76 {
  77         snd_soc_set_runtime_hwparams(substream, &dummy_dma_hardware);
  78
  79         return 0;
  80 }
  81
  82 static struct snd_pcm_ops dummy_dma_ops = {
  83         .open           = dummy_dma_open,
  84         .ioctl          = snd_pcm_lib_ioctl,
  85 };
  86
  87 static struct snd_soc_platform_driver dummy_platform = {
  88         .ops = &dummy_dma_ops,
  89 };
  90
  91 static __devinit int snd_soc_dummy_probe(struct platform_device *pdev)
  92 {
  93         return snd_soc_register_platform(&pdev->dev, &dummy_platform);
  94 }
  95
  96 static __devexit int snd_soc_dummy_remove(struct platform_device *pdev)
  97 {
  98         snd_soc_unregister_platform(&pdev->dev);
  99
 100         return 0;
 101 }
 102
 103 static struct platform_driver soc_dummy_driver = {
 104         .driver = {
 105                 .name = "snd-soc-dummy",
 106                 .owner = THIS_MODULE,
 107         },
 108         .probe = snd_soc_dummy_probe,
 109         .remove = __devexit_p(snd_soc_dummy_remove),
 110 };
 111
 112 static struct platform_device *soc_dummy_dev;
 113
 114 int __init snd_soc_util_init(void)
 115 {
 116         int ret;
 117
 118         soc_dummy_dev = platform_device_alloc("snd-soc-dummy", -1);
 119         if (!soc_dummy_dev)
 120                 return -ENOMEM;
 121
 122         ret = platform_device_add(soc_dummy_dev);
 123         if (ret != 0) {
 124                 platform_device_put(soc_dummy_dev);
 125                 return ret;
 126         }
 127
 128         ret = platform_driver_register(&soc_dummy_driver);
 129         if (ret != 0)
 130                 platform_device_unregister(soc_dummy_dev);
 131
 132         return ret;
 133 }
 134
 135 void __exit snd_soc_util_exit(void)
 136 {
 137         platform_device_unregister(soc_dummy_dev);
 138         platform_driver_unregister(&soc_dummy_driver);
 139 }