sound/soc/bcm/rpi-proto.c

   1 /*
   2  * ASoC driver for PROTO AudioCODEC (with a WM8731)
   3  * connected to a Raspberry Pi
   4  *
   5  * Author:      Florian Meier, <koalo@koalo.de>
   6  *            Copyright 2013
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15
  16 #include <sound/core.h>
  17 #include <sound/pcm.h>
  18 #include <sound/soc.h>
  19 #include <sound/jack.h>
  20
  21 #include "../codecs/wm8731.h"
  22
  23 static const unsigned int wm8731_rates_12288000[] = {
  24         8000, 32000, 48000, 96000,
  25 };
  26
  27 static struct snd_pcm_hw_constraint_list wm8731_constraints_12288000 = {
  28         .list = wm8731_rates_12288000,
  29         .count = ARRAY_SIZE(wm8731_rates_12288000),
  30 };
  31
  32 static int snd_rpi_proto_startup(struct snd_pcm_substream *substream)
  33 {
  34         /* Setup constraints, because there is a 12.288 MHz XTAL on the board */
  35         snd_pcm_hw_constraint_list(substream->runtime, 0,
  36                                 SNDRV_PCM_HW_PARAM_RATE,
  37                                 &wm8731_constraints_12288000);
  38         return 0;
  39 }
  40
  41 static int snd_rpi_proto_hw_params(struct snd_pcm_substream *substream,
  42                                        struct snd_pcm_hw_params *params)
  43 {
  44         struct snd_soc_pcm_runtime *rtd = substream->private_data;
  45         struct snd_soc_dai *codec_dai = asoc_rtd_to_codec(rtd, 0);
  46         struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
  47         int sysclk = 12288000; /* This is fixed on this board */
  48
  49         /* Set proto bclk */
  50         int ret = snd_soc_dai_set_bclk_ratio(cpu_dai,32*2);
  51         if (ret < 0){
  52                 dev_err(rtd->card->dev,
  53                                 "Failed to set BCLK ratio %d\n", ret);
  54                 return ret;
  55         }
  56
  57         /* Set proto sysclk */
  58         ret = snd_soc_dai_set_sysclk(codec_dai, WM8731_SYSCLK_XTAL,
  59                         sysclk, SND_SOC_CLOCK_IN);
  60         if (ret < 0) {
  61                 dev_err(rtd->card->dev,
  62                                 "Failed to set WM8731 SYSCLK: %d\n", ret);
  63                 return ret;
  64         }
  65
  66         return 0;
  67 }
  68
  69 /* machine stream operations */
  70 static struct snd_soc_ops snd_rpi_proto_ops = {
  71         .startup = snd_rpi_proto_startup,
  72         .hw_params = snd_rpi_proto_hw_params,
  73 };
  74
  75 SND_SOC_DAILINK_DEFS(rpi_proto,
  76         DAILINK_COMP_ARRAY(COMP_CPU("bcm2708-i2s.0")),
  77         DAILINK_COMP_ARRAY(COMP_CODEC("wm8731.1-001a", "wm8731-hifi")),
  78         DAILINK_COMP_ARRAY(COMP_PLATFORM("bcm2708-i2s.0")));
  79
  80 static struct snd_soc_dai_link snd_rpi_proto_dai[] = {
  81 {
  82         .name           = "WM8731",
  83         .stream_name    = "WM8731 HiFi",
  84         .dai_fmt        = SND_SOC_DAIFMT_I2S
  85                                 | SND_SOC_DAIFMT_NB_NF
  86                                 | SND_SOC_DAIFMT_CBM_CFM,
  87         .ops            = &snd_rpi_proto_ops,
  88         SND_SOC_DAILINK_REG(rpi_proto),
  89 },
  90 };
  91
  92 /* audio machine driver */
  93 static struct snd_soc_card snd_rpi_proto = {
  94         .name           = "snd_rpi_proto",
  95         .owner          = THIS_MODULE,
  96         .dai_link       = snd_rpi_proto_dai,
  97         .num_links      = ARRAY_SIZE(snd_rpi_proto_dai),
  98 };
  99
 100 static int snd_rpi_proto_probe(struct platform_device *pdev)
 101 {
 102         int ret = 0;
 103
 104         snd_rpi_proto.dev = &pdev->dev;
 105
 106         if (pdev->dev.of_node) {
 107                 struct device_node *i2s_node;
 108                 struct snd_soc_dai_link *dai = &snd_rpi_proto_dai[0];
 109                 i2s_node = of_parse_phandle(pdev->dev.of_node,
 110                                             "i2s-controller", 0);
 111
 112                 if (i2s_node) {
 113                         dai->cpus->dai_name = NULL;
 114                         dai->cpus->of_node = i2s_node;
 115                         dai->platforms->name = NULL;
 116                         dai->platforms->of_node = i2s_node;
 117                 }
 118         }
 119
 120         ret = devm_snd_soc_register_card(&pdev->dev, &snd_rpi_proto);
 121         if (ret && ret != -EPROBE_DEFER)
 122                 dev_err(&pdev->dev,
 123                                 "snd_soc_register_card() failed: %d\n", ret);
 124
 125         return ret;
 126 }
 127
 128 static const struct of_device_id snd_rpi_proto_of_match[] = {
 129         { .compatible = "rpi,rpi-proto", },
 130         {},
 131 };
 132 MODULE_DEVICE_TABLE(of, snd_rpi_proto_of_match);
 133
 134 static struct platform_driver snd_rpi_proto_driver = {
 135         .driver = {
 136                 .name   = "snd-rpi-proto",
 137                 .owner  = THIS_MODULE,
 138                 .of_match_table = snd_rpi_proto_of_match,
 139         },
 140         .probe    = snd_rpi_proto_probe,
 141 };
 142
 143 module_platform_driver(snd_rpi_proto_driver);
 144
 145 MODULE_AUTHOR("Florian Meier");
 146 MODULE_DESCRIPTION("ASoC Driver for Raspberry Pi connected to PROTO board (WM8731)");
 147 MODULE_LICENSE("GPL");