sound/soc/codecs/ak5386.c

   1 /*
   2  * ALSA SoC driver for
   3  *    Asahi Kasei AK5386 Single-ended 24-Bit 192kHz delta-sigma ADC
   4  *
   5  * (c) 2013 Daniel Mack <zonque@gmail.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/of.h>
  15 #include <linux/of_gpio.h>
  16 #include <linux/of_device.h>
  17 #include <sound/soc.h>
  18 #include <sound/pcm.h>
  19 #include <sound/initval.h>
  20
  21 struct ak5386_priv {
  22         int reset_gpio;
  23 };
  24
  25 static const struct snd_soc_dapm_widget ak5386_dapm_widgets[] = {
  26 SND_SOC_DAPM_INPUT("AINL"),
  27 SND_SOC_DAPM_INPUT("AINR"),
  28 };
  29
  30 static const struct snd_soc_dapm_route ak5386_dapm_routes[] = {
  31         { "Capture", NULL, "AINL" },
  32         { "Capture", NULL, "AINR" },
  33 };
  34
  35 static struct snd_soc_codec_driver soc_codec_ak5386 = {
  36         .dapm_widgets = ak5386_dapm_widgets,
  37         .num_dapm_widgets = ARRAY_SIZE(ak5386_dapm_widgets),
  38         .dapm_routes = ak5386_dapm_routes,
  39         .num_dapm_routes = ARRAY_SIZE(ak5386_dapm_routes),
  40 };
  41
  42 static int ak5386_set_dai_fmt(struct snd_soc_dai *codec_dai,
  43                               unsigned int format)
  44 {
  45         struct snd_soc_codec *codec = codec_dai->codec;
  46
  47         format &= SND_SOC_DAIFMT_FORMAT_MASK;
  48         if (format != SND_SOC_DAIFMT_LEFT_J &&
  49             format != SND_SOC_DAIFMT_I2S) {
  50                 dev_err(codec->dev, "Invalid DAI format\n");
  51                 return -EINVAL;
  52         }
  53
  54         return 0;
  55 }
  56
  57 static int ak5386_hw_params(struct snd_pcm_substream *substream,
  58                             struct snd_pcm_hw_params *params,
  59                             struct snd_soc_dai *dai)
  60 {
  61         struct snd_soc_codec *codec = dai->codec;
  62         struct ak5386_priv *priv = snd_soc_codec_get_drvdata(codec);
  63
  64         /*
  65          * From the datasheet:
  66          *
  67          * All external clocks (MCLK, SCLK and LRCK) must be present unless
  68          * PDN pin = “L”. If these clocks are not provided, the AK5386 may
  69          * draw excess current due to its use of internal dynamically
  70          * refreshed logic. If the external clocks are not present, place
  71          * the AK5386 in power-down mode (PDN pin = “L”).
  72          */
  73
  74         if (gpio_is_valid(priv->reset_gpio))
  75                 gpio_set_value(priv->reset_gpio, 1);
  76
  77         return 0;
  78 }
  79
  80 static int ak5386_hw_free(struct snd_pcm_substream *substream,
  81                           struct snd_soc_dai *dai)
  82 {
  83         struct snd_soc_codec *codec = dai->codec;
  84         struct ak5386_priv *priv = snd_soc_codec_get_drvdata(codec);
  85
  86         if (gpio_is_valid(priv->reset_gpio))
  87                 gpio_set_value(priv->reset_gpio, 0);
  88
  89         return 0;
  90 }
  91
  92 static const struct snd_soc_dai_ops ak5386_dai_ops = {
  93         .set_fmt        = ak5386_set_dai_fmt,
  94         .hw_params      = ak5386_hw_params,
  95         .hw_free        = ak5386_hw_free,
  96 };
  97
  98 static struct snd_soc_dai_driver ak5386_dai = {
  99         .name           = "ak5386-hifi",
 100         .capture        = {
 101                 .stream_name    = "Capture",
 102                 .channels_min   = 1,
 103                 .channels_max   = 2,
 104                 .rates          = SNDRV_PCM_RATE_8000_192000,
 105                 .formats        = SNDRV_PCM_FMTBIT_S8     |
 106                                   SNDRV_PCM_FMTBIT_S16_LE |
 107                                   SNDRV_PCM_FMTBIT_S24_LE |
 108                                   SNDRV_PCM_FMTBIT_S24_3LE,
 109         },
 110         .ops    = &ak5386_dai_ops,
 111 };
 112
 113 #ifdef CONFIG_OF
 114 static const struct of_device_id ak5386_dt_ids[] = {
 115         { .compatible = "asahi-kasei,ak5386", },
 116         { }
 117 };
 118 MODULE_DEVICE_TABLE(of, ak5386_dt_ids);
 119 #endif
 120
 121 static int ak5386_probe(struct platform_device *pdev)
 122 {
 123         struct device *dev = &pdev->dev;
 124         struct ak5386_priv *priv;
 125
 126         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 127         if (!priv)
 128                 return -ENOMEM;
 129
 130         priv->reset_gpio = -EINVAL;
 131         dev_set_drvdata(dev, priv);
 132
 133         if (of_match_device(of_match_ptr(ak5386_dt_ids), dev))
 134                 priv->reset_gpio = of_get_named_gpio(dev->of_node,
 135                                                       "reset-gpio", 0);
 136
 137         if (gpio_is_valid(priv->reset_gpio))
 138                 if (devm_gpio_request_one(dev, priv->reset_gpio,
 139                                           GPIOF_OUT_INIT_LOW,
 140                                           "AK5386 Reset"))
 141                         priv->reset_gpio = -EINVAL;
 142
 143         return snd_soc_register_codec(dev, &soc_codec_ak5386,
 144                                       &ak5386_dai, 1);
 145 }
 146
 147 static int ak5386_remove(struct platform_device *pdev)
 148 {
 149         snd_soc_unregister_codec(&pdev->dev);
 150         return 0;
 151 }
 152
 153 static struct platform_driver ak5386_driver = {
 154         .probe          = ak5386_probe,
 155         .remove         = ak5386_remove,
 156         .driver         = {
 157                 .name   = "ak5386",
 158                 .owner  = THIS_MODULE,
 159                 .of_match_table = of_match_ptr(ak5386_dt_ids),
 160         },
 161 };
 162
 163 module_platform_driver(ak5386_driver);
 164
 165 MODULE_DESCRIPTION("ASoC driver for AK5386 ADC");
 166 MODULE_AUTHOR("Daniel Mack <zonque@gmail.com>");
 167 MODULE_LICENSE("GPL");