sound/soc/codecs/dmic.c

   1 /*
   2  * dmic.c  --  SoC audio for Generic Digital MICs
   3  *
   4  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  18  * 02110-1301 USA
  19  *
  20  */
  21
  22 #include <linux/delay.h>
  23 #include <linux/gpio.h>
  24 #include <linux/gpio/consumer.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/slab.h>
  27 #include <linux/module.h>
  28 #include <sound/core.h>
  29 #include <sound/pcm.h>
  30 #include <sound/soc.h>
  31 #include <sound/soc-dapm.h>
  32
  33 #define MAX_MODESWITCH_DELAY 70
  34 static int modeswitch_delay;
  35 module_param(modeswitch_delay, uint, 0644);
  36
  37 static int wakeup_delay;
  38 module_param(wakeup_delay, uint, 0644);
  39
  40 struct dmic {
  41         struct gpio_desc *gpio_en;
  42         int wakeup_delay;
  43         /* Delay after DMIC mode switch */
  44         int modeswitch_delay;
  45 };
  46
  47 static int dmic_daiops_trigger(struct snd_pcm_substream *substream,
  48                                int cmd, struct snd_soc_dai *dai)
  49 {
  50         struct snd_soc_component *component = dai->component;
  51         struct dmic *dmic = snd_soc_component_get_drvdata(component);
  52
  53         switch (cmd) {
  54         case SNDRV_PCM_TRIGGER_STOP:
  55                 if (dmic->modeswitch_delay)
  56                         mdelay(dmic->modeswitch_delay);
  57
  58                 break;
  59         }
  60
  61         return 0;
  62 }
  63
  64 static const struct snd_soc_dai_ops dmic_dai_ops = {
  65         .trigger        = dmic_daiops_trigger,
  66 };
  67
  68 static int dmic_aif_event(struct snd_soc_dapm_widget *w,
  69                           struct snd_kcontrol *kcontrol, int event) {
  70         struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
  71         struct dmic *dmic = snd_soc_component_get_drvdata(component);
  72
  73         switch (event) {
  74         case SND_SOC_DAPM_POST_PMU:
  75                 if (dmic->gpio_en)
  76                         gpiod_set_value(dmic->gpio_en, 1);
  77
  78                 if (dmic->wakeup_delay)
  79                         msleep(dmic->wakeup_delay);
  80                 break;
  81         case SND_SOC_DAPM_POST_PMD:
  82                 if (dmic->gpio_en)
  83                         gpiod_set_value(dmic->gpio_en, 0);
  84                 break;
  85         }
  86
  87         return 0;
  88 }
  89
  90 static struct snd_soc_dai_driver dmic_dai = {
  91         .name = "dmic-hifi",
  92         .capture = {
  93                 .stream_name = "Capture",
  94                 .channels_min = 1,
  95                 .channels_max = 8,
  96                 .rates = SNDRV_PCM_RATE_CONTINUOUS,
  97                 .formats = SNDRV_PCM_FMTBIT_S32_LE
  98                         | SNDRV_PCM_FMTBIT_S24_LE
  99                         | SNDRV_PCM_FMTBIT_S16_LE,
 100         },
 101         .ops    = &dmic_dai_ops,
 102 };
 103
 104 static int dmic_component_probe(struct snd_soc_component *component)
 105 {
 106         struct dmic *dmic;
 107
 108         dmic = devm_kzalloc(component->dev, sizeof(*dmic), GFP_KERNEL);
 109         if (!dmic)
 110                 return -ENOMEM;
 111
 112         dmic->gpio_en = devm_gpiod_get_optional(component->dev,
 113                                                 "dmicen", GPIOD_OUT_LOW);
 114         if (IS_ERR(dmic->gpio_en))
 115                 return PTR_ERR(dmic->gpio_en);
 116
 117         device_property_read_u32(component->dev, "wakeup-delay-ms",
 118                                  &dmic->wakeup_delay);
 119         device_property_read_u32(component->dev, "modeswitch-delay-ms",
 120                                  &dmic->modeswitch_delay);
 121         if (wakeup_delay)
 122                 dmic->wakeup_delay  = wakeup_delay;
 123         if (modeswitch_delay)
 124                 dmic->modeswitch_delay  = modeswitch_delay;
 125
 126         if (dmic->modeswitch_delay > MAX_MODESWITCH_DELAY)
 127                 dmic->modeswitch_delay = MAX_MODESWITCH_DELAY;
 128
 129         snd_soc_component_set_drvdata(component, dmic);
 130
 131         return 0;
 132 }
 133
 134 static const struct snd_soc_dapm_widget dmic_dapm_widgets[] = {
 135         SND_SOC_DAPM_AIF_OUT_E("DMIC AIF", "Capture", 0,
 136                                SND_SOC_NOPM, 0, 0, dmic_aif_event,
 137                                SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD),
 138         SND_SOC_DAPM_INPUT("DMic"),
 139 };
 140
 141 static const struct snd_soc_dapm_route intercon[] = {
 142         {"DMIC AIF", NULL, "DMic"},
 143 };
 144
 145 static const struct snd_soc_component_driver soc_dmic = {
 146         .probe                  = dmic_component_probe,
 147         .dapm_widgets           = dmic_dapm_widgets,
 148         .num_dapm_widgets       = ARRAY_SIZE(dmic_dapm_widgets),
 149         .dapm_routes            = intercon,
 150         .num_dapm_routes        = ARRAY_SIZE(intercon),
 151         .idle_bias_on           = 1,
 152         .use_pmdown_time        = 1,
 153         .endianness             = 1,
 154         .non_legacy_dai_naming  = 1,
 155 };
 156
 157 static int dmic_dev_probe(struct platform_device *pdev)
 158 {
 159         int err;
 160         u32 chans;
 161         struct snd_soc_dai_driver *dai_drv = &dmic_dai;
 162
 163         if (pdev->dev.of_node) {
 164                 err = of_property_read_u32(pdev->dev.of_node, "num-channels", &chans);
 165                 if (err && (err != -EINVAL))
 166                         return err;
 167
 168                 if (!err) {
 169                         if (chans < 1 || chans > 8)
 170                                 return -EINVAL;
 171
 172                         dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL);
 173                         if (!dai_drv)
 174                                 return -ENOMEM;
 175
 176                         memcpy(dai_drv, &dmic_dai, sizeof(*dai_drv));
 177                         dai_drv->capture.channels_max = chans;
 178                 }
 179         }
 180
 181         return devm_snd_soc_register_component(&pdev->dev,
 182                         &soc_dmic, dai_drv, 1);
 183 }
 184
 185 MODULE_ALIAS("platform:dmic-codec");
 186
 187 static const struct of_device_id dmic_dev_match[] = {
 188         {.compatible = "dmic-codec"},
 189         {}
 190 };
 191 MODULE_DEVICE_TABLE(of, dmic_dev_match);
 192
 193 static struct platform_driver dmic_driver = {
 194         .driver = {
 195                 .name = "dmic-codec",
 196                 .of_match_table = dmic_dev_match,
 197         },
 198         .probe = dmic_dev_probe,
 199 };
 200
 201 module_platform_driver(dmic_driver);
 202
 203 MODULE_DESCRIPTION("Generic DMIC driver");
 204 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
 205 MODULE_LICENSE("GPL");