target/linux/brcm2708/patches-4.4/0068-Add-IQaudIO-Sound-Card-support-for-Raspberry-Pi.patch

   1 From dc2bd1c4b038c4f2d921808891b69a803805d984 Mon Sep 17 00:00:00 2001
   2 From: Gordon Garrity <gordon@iqaudio.com>
   3 Date: Sat, 8 Mar 2014 16:56:57 +0000
   4 Subject: [PATCH] Add IQaudIO Sound Card support for Raspberry Pi
   5
   6 Set a limit of 0dB on Digital Volume Control
   7
   8 The main volume control in the PCM512x DAC has a range up to
   9 +24dB. This is dangerously loud and can potentially cause massive
  10 clipping in the output stages. Therefore this sets a sensible
  11 limit of 0dB for this control.
  12 ---
  13  sound/soc/bcm/Kconfig       |   7 +++
  14  sound/soc/bcm/Makefile      |   2 +
  15  sound/soc/bcm/iqaudio-dac.c | 132 ++++++++++++++++++++++++++++++++++++++++++++
  16  3 files changed, 141 insertions(+)
  17  create mode 100644 sound/soc/bcm/iqaudio-dac.c
  18
  19 --- a/sound/soc/bcm/Kconfig
  20 +++ b/sound/soc/bcm/Kconfig
  21 @@ -28,3 +28,10 @@ config SND_BCM2708_SOC_RPI_DAC
  22          select SND_SOC_PCM1794A
  23          help
  24           Say Y or M if you want to add support for RPi-DAC.
  25 +
  26 +config SND_BCM2708_SOC_IQAUDIO_DAC
  27 +       tristate "Support for IQaudIO-DAC"
  28 +       depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S
  29 +       select SND_SOC_PCM512x_I2C
  30 +       help
  31 +         Say Y or M if you want to add support for IQaudIO-DAC.
  32 --- a/sound/soc/bcm/Makefile
  33 +++ b/sound/soc/bcm/Makefile
  34 @@ -7,7 +7,9 @@ obj-$(CONFIG_SND_BCM2835_SOC_I2S) += snd
  35  snd-soc-hifiberry-dac-objs := hifiberry_dac.o
  36  snd-soc-hifiberry-digi-objs := hifiberry_digi.o
  37  snd-soc-rpi-dac-objs := rpi-dac.o
  38 +snd-soc-iqaudio-dac-objs := iqaudio-dac.o
  39
  40  obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DAC) += snd-soc-hifiberry-dac.o
  41  obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DIGI) += snd-soc-hifiberry-digi.o
  42  obj-$(CONFIG_SND_BCM2708_SOC_RPI_DAC) += snd-soc-rpi-dac.o
  43 +obj-$(CONFIG_SND_BCM2708_SOC_IQAUDIO_DAC) += snd-soc-iqaudio-dac.o
  44 --- /dev/null
  45 +++ b/sound/soc/bcm/iqaudio-dac.c
  46 @@ -0,0 +1,132 @@
  47 +/*
  48 + * ASoC Driver for IQaudIO DAC
  49 + *
  50 + * Author:     Florian Meier <florian.meier@koalo.de>
  51 + *             Copyright 2013
  52 + *
  53 + * This program is free software; you can redistribute it and/or
  54 + * modify it under the terms of the GNU General Public License
  55 + * version 2 as published by the Free Software Foundation.
  56 + *
  57 + * This program is distributed in the hope that it will be useful, but
  58 + * WITHOUT ANY WARRANTY; without even the implied warranty of
  59 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  60 + * General Public License for more details.
  61 + */
  62 +
  63 +#include <linux/module.h>
  64 +#include <linux/platform_device.h>
  65 +
  66 +#include <sound/core.h>
  67 +#include <sound/pcm.h>
  68 +#include <sound/pcm_params.h>
  69 +#include <sound/soc.h>
  70 +#include <sound/jack.h>
  71 +
  72 +static int snd_rpi_iqaudio_dac_init(struct snd_soc_pcm_runtime *rtd)
  73 +{
  74 +       int ret;
  75 +       struct snd_soc_card *card = rtd->card;
  76 +
  77 +       ret = snd_soc_limit_volume(card, "Digital Playback Volume", 207);
  78 +       if (ret < 0)
  79 +               dev_warn(card->dev, "Failed to set volume limit: %d\n", ret);
  80 +
  81 +       return 0;
  82 +}
  83 +
  84 +static int snd_rpi_iqaudio_dac_hw_params(struct snd_pcm_substream *substream,
  85 +                                      struct snd_pcm_hw_params *params)
  86 +{
  87 +       struct snd_soc_pcm_runtime *rtd = substream->private_data;
  88 +// NOT USED    struct snd_soc_dai *codec_dai = rtd->codec_dai;
  89 +// NOT USED    struct snd_soc_codec *codec = rtd->codec;
  90 +       struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
  91 +
  92 +       unsigned int sample_bits =
  93 +               snd_pcm_format_physical_width(params_format(params));
  94 +
  95 +       return snd_soc_dai_set_bclk_ratio(cpu_dai, sample_bits * 2);
  96 +}
  97 +
  98 +/* machine stream operations */
  99 +static struct snd_soc_ops snd_rpi_iqaudio_dac_ops = {
 100 +       .hw_params = snd_rpi_iqaudio_dac_hw_params,
 101 +};
 102 +
 103 +static struct snd_soc_dai_link snd_rpi_iqaudio_dac_dai[] = {
 104 +{
 105 +       .name           = "IQaudIO DAC",
 106 +       .stream_name    = "IQaudIO DAC HiFi",
 107 +       .cpu_dai_name   = "bcm2708-i2s.0",
 108 +       .codec_dai_name = "pcm512x-hifi",
 109 +       .platform_name  = "bcm2708-i2s.0",
 110 +       .codec_name     = "pcm512x.1-004c",
 111 +       .dai_fmt        = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
 112 +                               SND_SOC_DAIFMT_CBS_CFS,
 113 +       .ops            = &snd_rpi_iqaudio_dac_ops,
 114 +       .init           = snd_rpi_iqaudio_dac_init,
 115 +},
 116 +};
 117 +
 118 +/* audio machine driver */
 119 +static struct snd_soc_card snd_rpi_iqaudio_dac = {
 120 +       .name         = "IQaudIODAC",
 121 +       .dai_link     = snd_rpi_iqaudio_dac_dai,
 122 +       .num_links    = ARRAY_SIZE(snd_rpi_iqaudio_dac_dai),
 123 +};
 124 +
 125 +static int snd_rpi_iqaudio_dac_probe(struct platform_device *pdev)
 126 +{
 127 +       int ret = 0;
 128 +
 129 +       snd_rpi_iqaudio_dac.dev = &pdev->dev;
 130 +
 131 +       if (pdev->dev.of_node) {
 132 +           struct device_node *i2s_node;
 133 +           struct snd_soc_dai_link *dai = &snd_rpi_iqaudio_dac_dai[0];
 134 +           i2s_node = of_parse_phandle(pdev->dev.of_node,
 135 +                                       "i2s-controller", 0);
 136 +
 137 +           if (i2s_node) {
 138 +               dai->cpu_dai_name = NULL;
 139 +               dai->cpu_of_node = i2s_node;
 140 +               dai->platform_name = NULL;
 141 +               dai->platform_of_node = i2s_node;
 142 +           }
 143 +       }
 144 +
 145 +       ret = snd_soc_register_card(&snd_rpi_iqaudio_dac);
 146 +       if (ret)
 147 +               dev_err(&pdev->dev,
 148 +                       "snd_soc_register_card() failed: %d\n", ret);
 149 +
 150 +       return ret;
 151 +}
 152 +
 153 +static int snd_rpi_iqaudio_dac_remove(struct platform_device *pdev)
 154 +{
 155 +       return snd_soc_unregister_card(&snd_rpi_iqaudio_dac);
 156 +}
 157 +
 158 +static const struct of_device_id iqaudio_of_match[] = {
 159 +       { .compatible = "iqaudio,iqaudio-dac", },
 160 +       {},
 161 +};
 162 +MODULE_DEVICE_TABLE(of, iqaudio_of_match);
 163 +
 164 +static struct platform_driver snd_rpi_iqaudio_dac_driver = {
 165 +       .driver = {
 166 +               .name   = "snd-rpi-iqaudio-dac",
 167 +               .owner  = THIS_MODULE,
 168 +               .of_match_table = iqaudio_of_match,
 169 +       },
 170 +       .probe          = snd_rpi_iqaudio_dac_probe,
 171 +       .remove         = snd_rpi_iqaudio_dac_remove,
 172 +};
 173 +
 174 +module_platform_driver(snd_rpi_iqaudio_dac_driver);
 175 +
 176 +MODULE_AUTHOR("Florian Meier <florian.meier@koalo.de>");
 177 +MODULE_DESCRIPTION("ASoC Driver for IQAudio DAC");
 178 +MODULE_LICENSE("GPL v2");