sound/soc/soc-utils.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // soc-util.c  --  ALSA SoC Audio Layer utility functions
   4 //
   5 // Copyright 2009 Wolfson Microelectronics PLC.
   6 //
   7 // Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   8 //         Liam Girdwood <lrg@slimlogic.co.uk>
   9
  10 #include <linux/platform_device.h>
  11 #include <linux/export.h>
  12 #include <sound/core.h>
  13 #include <sound/pcm.h>
  14 #include <sound/pcm_params.h>
  15 #include <sound/soc.h>
  16
  17 int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots)
  18 {
  19         return sample_size * channels * tdm_slots;
  20 }
  21 EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size);
  22
  23 int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params)
  24 {
  25         int sample_size;
  26
  27         sample_size = snd_pcm_format_width(params_format(params));
  28         if (sample_size < 0)
  29                 return sample_size;
  30
  31         return snd_soc_calc_frame_size(sample_size, params_channels(params),
  32                                        1);
  33 }
  34 EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size);
  35
  36 int snd_soc_calc_bclk(int fs, int sample_size, int channels, int tdm_slots)
  37 {
  38         return fs * snd_soc_calc_frame_size(sample_size, channels, tdm_slots);
  39 }
  40 EXPORT_SYMBOL_GPL(snd_soc_calc_bclk);
  41
  42 int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params)
  43 {
  44         int ret;
  45
  46         ret = snd_soc_params_to_frame_size(params);
  47
  48         if (ret > 0)
  49                 return ret * params_rate(params);
  50         else
  51                 return ret;
  52 }
  53 EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk);
  54
  55 static const struct snd_pcm_hardware dummy_dma_hardware = {
  56         /* Random values to keep userspace happy when checking constraints */
  57         .info                   = SNDRV_PCM_INFO_INTERLEAVED |
  58                                   SNDRV_PCM_INFO_BLOCK_TRANSFER,
  59         .buffer_bytes_max       = 128*1024,
  60         .period_bytes_min       = PAGE_SIZE,
  61         .period_bytes_max       = PAGE_SIZE*2,
  62         .periods_min            = 2,
  63         .periods_max            = 128,
  64 };
  65
  66 static int dummy_dma_open(struct snd_soc_component *component,
  67                           struct snd_pcm_substream *substream)
  68 {
  69         struct snd_soc_pcm_runtime *rtd = substream->private_data;
  70
  71         /* BE's dont need dummy params */
  72         if (!rtd->dai_link->no_pcm)
  73                 snd_soc_set_runtime_hwparams(substream, &dummy_dma_hardware);
  74
  75         return 0;
  76 }
  77
  78 static const struct snd_soc_component_driver dummy_platform = {
  79         .open           = dummy_dma_open,
  80 };
  81
  82 static const struct snd_soc_component_driver dummy_codec = {
  83         .idle_bias_on           = 1,
  84         .use_pmdown_time        = 1,
  85         .endianness             = 1,
  86         .non_legacy_dai_naming  = 1,
  87 };
  88
  89 #define STUB_RATES      SNDRV_PCM_RATE_8000_192000
  90 #define STUB_FORMATS    (SNDRV_PCM_FMTBIT_S8 | \
  91                         SNDRV_PCM_FMTBIT_U8 | \
  92                         SNDRV_PCM_FMTBIT_S16_LE | \
  93                         SNDRV_PCM_FMTBIT_U16_LE | \
  94                         SNDRV_PCM_FMTBIT_S24_LE | \
  95                         SNDRV_PCM_FMTBIT_U24_LE | \
  96                         SNDRV_PCM_FMTBIT_S32_LE | \
  97                         SNDRV_PCM_FMTBIT_U32_LE | \
  98                         SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE)
  99 /*
 100  * The dummy CODEC is only meant to be used in situations where there is no
 101  * actual hardware.
 102  *
 103  * If there is actual hardware even if it does not have a control bus
 104  * the hardware will still have constraints like supported samplerates, etc.
 105  * which should be modelled. And the data flow graph also should be modelled
 106  * using DAPM.
 107  */
 108 static struct snd_soc_dai_driver dummy_dai = {
 109         .name = "snd-soc-dummy-dai",
 110         .playback = {
 111                 .stream_name    = "Playback",
 112                 .channels_min   = 1,
 113                 .channels_max   = 384,
 114                 .rates          = STUB_RATES,
 115                 .formats        = STUB_FORMATS,
 116         },
 117         .capture = {
 118                 .stream_name    = "Capture",
 119                 .channels_min   = 1,
 120                 .channels_max   = 384,
 121                 .rates = STUB_RATES,
 122                 .formats = STUB_FORMATS,
 123          },
 124 };
 125
 126 int snd_soc_dai_is_dummy(struct snd_soc_dai *dai)
 127 {
 128         if (dai->driver == &dummy_dai)
 129                 return 1;
 130         return 0;
 131 }
 132
 133 static int snd_soc_dummy_probe(struct platform_device *pdev)
 134 {
 135         int ret;
 136
 137         ret = devm_snd_soc_register_component(&pdev->dev,
 138                                               &dummy_codec, &dummy_dai, 1);
 139         if (ret < 0)
 140                 return ret;
 141
 142         ret = devm_snd_soc_register_component(&pdev->dev, &dummy_platform,
 143                                               NULL, 0);
 144
 145         return ret;
 146 }
 147
 148 static struct platform_driver soc_dummy_driver = {
 149         .driver = {
 150                 .name = "snd-soc-dummy",
 151         },
 152         .probe = snd_soc_dummy_probe,
 153 };
 154
 155 static struct platform_device *soc_dummy_dev;
 156
 157 int __init snd_soc_util_init(void)
 158 {
 159         int ret;
 160
 161         soc_dummy_dev =
 162                 platform_device_register_simple("snd-soc-dummy", -1, NULL, 0);
 163         if (IS_ERR(soc_dummy_dev))
 164                 return PTR_ERR(soc_dummy_dev);
 165
 166         ret = platform_driver_register(&soc_dummy_driver);
 167         if (ret != 0)
 168                 platform_device_unregister(soc_dummy_dev);
 169
 170         return ret;
 171 }
 172
 173 void __exit snd_soc_util_exit(void)
 174 {
 175         platform_driver_unregister(&soc_dummy_driver);
 176         platform_device_unregister(soc_dummy_dev);
 177 }