sound/soc/codecs/spdif_transmitter.c

   1 /*
   2  * ALSA SoC SPDIF DIT driver
   3  *
   4  *  This driver is used by controllers which can operate in DIT (SPDI/F) where
   5  *  no codec is needed.  This file provides stub codec that can be used
   6  *  in these configurations. TI DaVinci Audio controller uses this driver.
   7  *
   8  * Author:      Steve Chen,  <schen@mvista.com>
   9  * Copyright:   (C) 2009 MontaVista Software, Inc., <source@mvista.com>
  10  * Copyright:   (C) 2009  Texas Instruments, India
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/slab.h>
  20 #include <sound/soc.h>
  21 #include <sound/pcm.h>
  22 #include <sound/initval.h>
  23 #include <linux/of.h>
  24
  25 #define DRV_NAME "spdif-dit"
  26
  27 #define STUB_RATES      SNDRV_PCM_RATE_8000_192000
  28 #define STUB_FORMATS    (SNDRV_PCM_FMTBIT_S16_LE | \
  29                         SNDRV_PCM_FMTBIT_S20_3LE | \
  30                         SNDRV_PCM_FMTBIT_S24_LE  | \
  31                         SNDRV_PCM_FMTBIT_S32_LE)
  32
  33 static const struct snd_soc_dapm_widget dit_widgets[] = {
  34         SND_SOC_DAPM_OUTPUT("spdif-out"),
  35 };
  36
  37 static const struct snd_soc_dapm_route dit_routes[] = {
  38         { "spdif-out", NULL, "Playback" },
  39 };
  40
  41 static struct snd_soc_codec_driver soc_codec_spdif_dit = {
  42         .component_driver = {
  43                 .dapm_widgets           = dit_widgets,
  44                 .num_dapm_widgets       = ARRAY_SIZE(dit_widgets),
  45                 .dapm_routes            = dit_routes,
  46                 .num_dapm_routes        = ARRAY_SIZE(dit_routes),
  47         },
  48 };
  49
  50 static struct snd_soc_dai_driver dit_stub_dai = {
  51         .name           = "dit-hifi",
  52         .playback       = {
  53                 .stream_name    = "Playback",
  54                 .channels_min   = 1,
  55                 .channels_max   = 384,
  56                 .rates          = STUB_RATES,
  57                 .formats        = STUB_FORMATS,
  58         },
  59 };
  60
  61 static int spdif_dit_probe(struct platform_device *pdev)
  62 {
  63         return snd_soc_register_codec(&pdev->dev, &soc_codec_spdif_dit,
  64                         &dit_stub_dai, 1);
  65 }
  66
  67 static int spdif_dit_remove(struct platform_device *pdev)
  68 {
  69         snd_soc_unregister_codec(&pdev->dev);
  70         return 0;
  71 }
  72
  73 #ifdef CONFIG_OF
  74 static const struct of_device_id spdif_dit_dt_ids[] = {
  75         { .compatible = "linux,spdif-dit", },
  76         { }
  77 };
  78 MODULE_DEVICE_TABLE(of, spdif_dit_dt_ids);
  79 #endif
  80
  81 static struct platform_driver spdif_dit_driver = {
  82         .probe          = spdif_dit_probe,
  83         .remove         = spdif_dit_remove,
  84         .driver         = {
  85                 .name   = DRV_NAME,
  86                 .of_match_table = of_match_ptr(spdif_dit_dt_ids),
  87         },
  88 };
  89
  90 module_platform_driver(spdif_dit_driver);
  91
  92 MODULE_AUTHOR("Steve Chen <schen@mvista.com>");
  93 MODULE_DESCRIPTION("SPDIF dummy codec driver");
  94 MODULE_LICENSE("GPL");
  95 MODULE_ALIAS("platform:" DRV_NAME);