sound/soc/codecs/dmic.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * dmic.c  --  SoC audio for Generic Digital MICs
   4  *
   5  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
   6  */
   7
   8 #include <linux/delay.h>
   9 #include <linux/gpio.h>
  10 #include <linux/gpio/consumer.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/slab.h>
  13 #include <linux/module.h>
  14 #include <sound/core.h>
  15 #include <sound/pcm.h>
  16 #include <sound/soc.h>
  17 #include <sound/soc-dapm.h>
  18
  19 #define MAX_MODESWITCH_DELAY 70
  20 static int modeswitch_delay;
  21 module_param(modeswitch_delay, uint, 0644);
  22
  23 static int wakeup_delay;
  24 module_param(wakeup_delay, uint, 0644);
  25
  26 struct dmic {
  27         struct gpio_desc *gpio_en;
  28         int wakeup_delay;
  29         /* Delay after DMIC mode switch */
  30         int modeswitch_delay;
  31 };
  32
  33 static int dmic_daiops_trigger(struct snd_pcm_substream *substream,
  34                                int cmd, struct snd_soc_dai *dai)
  35 {
  36         struct snd_soc_component *component = dai->component;
  37         struct dmic *dmic = snd_soc_component_get_drvdata(component);
  38
  39         switch (cmd) {
  40         case SNDRV_PCM_TRIGGER_STOP:
  41                 if (dmic->modeswitch_delay)
  42                         mdelay(dmic->modeswitch_delay);
  43
  44                 break;
  45         }
  46
  47         return 0;
  48 }
  49
  50 static const struct snd_soc_dai_ops dmic_dai_ops = {
  51         .trigger        = dmic_daiops_trigger,
  52 };
  53
  54 static int dmic_aif_event(struct snd_soc_dapm_widget *w,
  55                           struct snd_kcontrol *kcontrol, int event) {
  56         struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
  57         struct dmic *dmic = snd_soc_component_get_drvdata(component);
  58
  59         switch (event) {
  60         case SND_SOC_DAPM_POST_PMU:
  61                 if (dmic->gpio_en)
  62                         gpiod_set_value(dmic->gpio_en, 1);
  63
  64                 if (dmic->wakeup_delay)
  65                         msleep(dmic->wakeup_delay);
  66                 break;
  67         case SND_SOC_DAPM_POST_PMD:
  68                 if (dmic->gpio_en)
  69                         gpiod_set_value(dmic->gpio_en, 0);
  70                 break;
  71         }
  72
  73         return 0;
  74 }
  75
  76 static struct snd_soc_dai_driver dmic_dai = {
  77         .name = "dmic-hifi",
  78         .capture = {
  79                 .stream_name = "Capture",
  80                 .channels_min = 1,
  81                 .channels_max = 8,
  82                 .rates = SNDRV_PCM_RATE_CONTINUOUS,
  83                 .formats = SNDRV_PCM_FMTBIT_S32_LE
  84                         | SNDRV_PCM_FMTBIT_S24_LE
  85                         | SNDRV_PCM_FMTBIT_S16_LE,
  86         },
  87         .ops    = &dmic_dai_ops,
  88 };
  89
  90 static int dmic_component_probe(struct snd_soc_component *component)
  91 {
  92         struct dmic *dmic;
  93
  94         dmic = devm_kzalloc(component->dev, sizeof(*dmic), GFP_KERNEL);
  95         if (!dmic)
  96                 return -ENOMEM;
  97
  98         dmic->gpio_en = devm_gpiod_get_optional(component->dev,
  99                                                 "dmicen", GPIOD_OUT_LOW);
 100         if (IS_ERR(dmic->gpio_en))
 101                 return PTR_ERR(dmic->gpio_en);
 102
 103         device_property_read_u32(component->dev, "wakeup-delay-ms",
 104                                  &dmic->wakeup_delay);
 105         device_property_read_u32(component->dev, "modeswitch-delay-ms",
 106                                  &dmic->modeswitch_delay);
 107         if (wakeup_delay)
 108                 dmic->wakeup_delay  = wakeup_delay;
 109         if (modeswitch_delay)
 110                 dmic->modeswitch_delay  = modeswitch_delay;
 111
 112         if (dmic->modeswitch_delay > MAX_MODESWITCH_DELAY)
 113                 dmic->modeswitch_delay = MAX_MODESWITCH_DELAY;
 114
 115         snd_soc_component_set_drvdata(component, dmic);
 116
 117         return 0;
 118 }
 119
 120 static const struct snd_soc_dapm_widget dmic_dapm_widgets[] = {
 121         SND_SOC_DAPM_AIF_OUT_E("DMIC AIF", "Capture", 0,
 122                                SND_SOC_NOPM, 0, 0, dmic_aif_event,
 123                                SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD),
 124         SND_SOC_DAPM_INPUT("DMic"),
 125 };
 126
 127 static const struct snd_soc_dapm_route intercon[] = {
 128         {"DMIC AIF", NULL, "DMic"},
 129 };
 130
 131 static const struct snd_soc_component_driver soc_dmic = {
 132         .probe                  = dmic_component_probe,
 133         .dapm_widgets           = dmic_dapm_widgets,
 134         .num_dapm_widgets       = ARRAY_SIZE(dmic_dapm_widgets),
 135         .dapm_routes            = intercon,
 136         .num_dapm_routes        = ARRAY_SIZE(intercon),
 137         .idle_bias_on           = 1,
 138         .use_pmdown_time        = 1,
 139         .endianness             = 1,
 140         .non_legacy_dai_naming  = 1,
 141 };
 142
 143 static int dmic_dev_probe(struct platform_device *pdev)
 144 {
 145         int err;
 146         u32 chans;
 147         struct snd_soc_dai_driver *dai_drv = &dmic_dai;
 148
 149         if (pdev->dev.of_node) {
 150                 err = of_property_read_u32(pdev->dev.of_node, "num-channels", &chans);
 151                 if (err && (err != -EINVAL))
 152                         return err;
 153
 154                 if (!err) {
 155                         if (chans < 1 || chans > 8)
 156                                 return -EINVAL;
 157
 158                         dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL);
 159                         if (!dai_drv)
 160                                 return -ENOMEM;
 161
 162                         memcpy(dai_drv, &dmic_dai, sizeof(*dai_drv));
 163                         dai_drv->capture.channels_max = chans;
 164                 }
 165         }
 166
 167         return devm_snd_soc_register_component(&pdev->dev,
 168                         &soc_dmic, dai_drv, 1);
 169 }
 170
 171 MODULE_ALIAS("platform:dmic-codec");
 172
 173 static const struct of_device_id dmic_dev_match[] = {
 174         {.compatible = "dmic-codec"},
 175         {}
 176 };
 177 MODULE_DEVICE_TABLE(of, dmic_dev_match);
 178
 179 static struct platform_driver dmic_driver = {
 180         .driver = {
 181                 .name = "dmic-codec",
 182                 .of_match_table = dmic_dev_match,
 183         },
 184         .probe = dmic_dev_probe,
 185 };
 186
 187 module_platform_driver(dmic_driver);
 188
 189 MODULE_DESCRIPTION("Generic DMIC driver");
 190 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
 191 MODULE_LICENSE("GPL");