target/linux/bcm27xx/patches-4.19/950-0069-Add-driver-for-rpi-proto.patch

   1 From bf4dee727fc7c72e250784e8e3e681f9d11bbdc1 Mon Sep 17 00:00:00 2001
   2 From: Waldemar Brodkorb <wbrodkorb@conet.de>
   3 Date: Wed, 25 Mar 2015 09:26:17 +0100
   4 Subject: [PATCH] Add driver for rpi-proto
   5
   6 Forward port of 3.10.x driver from https://github.com/koalo
   7 We are using a custom board and would like to use rpi 3.18.x
   8 kernel. Patch works fine for our embedded system.
   9
  10 URL to the audio chip:
  11 http://www.mikroe.com/add-on-boards/audio-voice/audio-codec-proto/
  12
  13 Playback tested with devicetree enabled.
  14
  15 Signed-off-by: Waldemar Brodkorb <wbrodkorb@conet.de>
  16 ---
  17  sound/soc/bcm/rpi-proto.c | 145 ++++++++++++++++++++++++++++++++++++++
  18  1 file changed, 145 insertions(+)
  19  create mode 100644 sound/soc/bcm/rpi-proto.c
  20
  21 --- /dev/null
  22 +++ b/sound/soc/bcm/rpi-proto.c
  23 @@ -0,0 +1,145 @@
  24 +/*
  25 + * ASoC driver for PROTO AudioCODEC (with a WM8731)
  26 + * connected to a Raspberry Pi
  27 + *
  28 + * Author:      Florian Meier, <koalo@koalo.de>
  29 + *           Copyright 2013
  30 + *
  31 + * This program is free software; you can redistribute it and/or modify
  32 + * it under the terms of the GNU General Public License version 2 as
  33 + * published by the Free Software Foundation.
  34 + */
  35 +
  36 +#include <linux/module.h>
  37 +#include <linux/platform_device.h>
  38 +
  39 +#include <sound/core.h>
  40 +#include <sound/pcm.h>
  41 +#include <sound/soc.h>
  42 +#include <sound/jack.h>
  43 +
  44 +#include "../codecs/wm8731.h"
  45 +
  46 +static const unsigned int wm8731_rates_12288000[] = {
  47 +       8000, 32000, 48000, 96000,
  48 +};
  49 +
  50 +static struct snd_pcm_hw_constraint_list wm8731_constraints_12288000 = {
  51 +       .list = wm8731_rates_12288000,
  52 +       .count = ARRAY_SIZE(wm8731_rates_12288000),
  53 +};
  54 +
  55 +static int snd_rpi_proto_startup(struct snd_pcm_substream *substream)
  56 +{
  57 +       /* Setup constraints, because there is a 12.288 MHz XTAL on the board */
  58 +       snd_pcm_hw_constraint_list(substream->runtime, 0,
  59 +                               SNDRV_PCM_HW_PARAM_RATE,
  60 +                               &wm8731_constraints_12288000);
  61 +       return 0;
  62 +}
  63 +
  64 +static int snd_rpi_proto_hw_params(struct snd_pcm_substream *substream,
  65 +                                      struct snd_pcm_hw_params *params)
  66 +{
  67 +       struct snd_soc_pcm_runtime *rtd = substream->private_data;
  68 +       struct snd_soc_dai *codec_dai = rtd->codec_dai;
  69 +       struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
  70 +       int sysclk = 12288000; /* This is fixed on this board */
  71 +
  72 +       /* Set proto bclk */
  73 +       int ret = snd_soc_dai_set_bclk_ratio(cpu_dai,32*2);
  74 +       if (ret < 0){
  75 +               dev_err(rtd->card->dev,
  76 +                               "Failed to set BCLK ratio %d\n", ret);
  77 +               return ret;
  78 +       }
  79 +
  80 +       /* Set proto sysclk */
  81 +       ret = snd_soc_dai_set_sysclk(codec_dai, WM8731_SYSCLK_XTAL,
  82 +                       sysclk, SND_SOC_CLOCK_IN);
  83 +       if (ret < 0) {
  84 +               dev_err(rtd->card->dev,
  85 +                               "Failed to set WM8731 SYSCLK: %d\n", ret);
  86 +               return ret;
  87 +       }
  88 +
  89 +       return 0;
  90 +}
  91 +
  92 +/* machine stream operations */
  93 +static struct snd_soc_ops snd_rpi_proto_ops = {
  94 +       .startup = snd_rpi_proto_startup,
  95 +       .hw_params = snd_rpi_proto_hw_params,
  96 +};
  97 +
  98 +static struct snd_soc_dai_link snd_rpi_proto_dai[] = {
  99 +{
 100 +       .name           = "WM8731",
 101 +       .stream_name    = "WM8731 HiFi",
 102 +       .cpu_dai_name   = "bcm2708-i2s.0",
 103 +       .codec_dai_name = "wm8731-hifi",
 104 +       .platform_name  = "bcm2708-i2s.0",
 105 +       .codec_name     = "wm8731.1-001a",
 106 +       .dai_fmt        = SND_SOC_DAIFMT_I2S
 107 +                               | SND_SOC_DAIFMT_NB_NF
 108 +                               | SND_SOC_DAIFMT_CBM_CFM,
 109 +       .ops            = &snd_rpi_proto_ops,
 110 +},
 111 +};
 112 +
 113 +/* audio machine driver */
 114 +static struct snd_soc_card snd_rpi_proto = {
 115 +       .name           = "snd_rpi_proto",
 116 +       .owner          = THIS_MODULE,
 117 +       .dai_link       = snd_rpi_proto_dai,
 118 +       .num_links      = ARRAY_SIZE(snd_rpi_proto_dai),
 119 +};
 120 +
 121 +static int snd_rpi_proto_probe(struct platform_device *pdev)
 122 +{
 123 +       int ret = 0;
 124 +
 125 +       snd_rpi_proto.dev = &pdev->dev;
 126 +
 127 +       if (pdev->dev.of_node) {
 128 +               struct device_node *i2s_node;
 129 +               struct snd_soc_dai_link *dai = &snd_rpi_proto_dai[0];
 130 +               i2s_node = of_parse_phandle(pdev->dev.of_node,
 131 +                                           "i2s-controller", 0);
 132 +
 133 +               if (i2s_node) {
 134 +                       dai->cpu_dai_name = NULL;
 135 +                       dai->cpu_of_node = i2s_node;
 136 +                       dai->platform_name = NULL;
 137 +                       dai->platform_of_node = i2s_node;
 138 +               }
 139 +       }
 140 +
 141 +       ret = devm_snd_soc_register_card(&pdev->dev, &snd_rpi_proto);
 142 +       if (ret && ret != -EPROBE_DEFER)
 143 +               dev_err(&pdev->dev,
 144 +                               "snd_soc_register_card() failed: %d\n", ret);
 145 +
 146 +       return ret;
 147 +}
 148 +
 149 +static const struct of_device_id snd_rpi_proto_of_match[] = {
 150 +       { .compatible = "rpi,rpi-proto", },
 151 +       {},
 152 +};
 153 +MODULE_DEVICE_TABLE(of, snd_rpi_proto_of_match);
 154 +
 155 +static struct platform_driver snd_rpi_proto_driver = {
 156 +       .driver = {
 157 +               .name   = "snd-rpi-proto",
 158 +               .owner  = THIS_MODULE,
 159 +               .of_match_table = snd_rpi_proto_of_match,
 160 +       },
 161 +       .probe    = snd_rpi_proto_probe,
 162 +};
 163 +
 164 +module_platform_driver(snd_rpi_proto_driver);
 165 +
 166 +MODULE_AUTHOR("Florian Meier");
 167 +MODULE_DESCRIPTION("ASoC Driver for Raspberry Pi connected to PROTO board (WM8731)");
 168 +MODULE_LICENSE("GPL");