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/gpio.h> 23 #include <linux/gpio/consumer.h> 24 #include <linux/platform_device.h> 25 #include <linux/slab.h> 26 #include <linux/module.h> 27 #include <sound/core.h> 28 #include <sound/pcm.h> 29 #include <sound/soc.h> 30 #include <sound/soc-dapm.h> 31 32 static int dmic_daiops_trigger(struct snd_pcm_substream *substream, 33 int cmd, struct snd_soc_dai *dai) 34 { 35 struct gpio_desc *dmic_en = snd_soc_dai_get_drvdata(dai); 36 37 if (!dmic_en) 38 return 0; 39 40 switch (cmd) { 41 case SNDRV_PCM_TRIGGER_START: 42 case SNDRV_PCM_TRIGGER_RESUME: 43 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 44 gpiod_set_value(dmic_en, 1); 45 break; 46 case SNDRV_PCM_TRIGGER_STOP: 47 case SNDRV_PCM_TRIGGER_SUSPEND: 48 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 49 gpiod_set_value(dmic_en, 0); 50 break; 51 } 52 53 return 0; 54 } 55 56 static const struct snd_soc_dai_ops dmic_dai_ops = { 57 .trigger = dmic_daiops_trigger, 58 }; 59 60 static struct snd_soc_dai_driver dmic_dai = { 61 .name = "dmic-hifi", 62 .capture = { 63 .stream_name = "Capture", 64 .channels_min = 1, 65 .channels_max = 8, 66 .rates = SNDRV_PCM_RATE_CONTINUOUS, 67 .formats = SNDRV_PCM_FMTBIT_S32_LE 68 | SNDRV_PCM_FMTBIT_S24_LE 69 | SNDRV_PCM_FMTBIT_S16_LE, 70 }, 71 .ops = &dmic_dai_ops, 72 }; 73 74 static int dmic_codec_probe(struct snd_soc_codec *codec) 75 { 76 struct gpio_desc *dmic_en; 77 78 dmic_en = devm_gpiod_get_optional(codec->dev, 79 "dmicen", GPIOD_OUT_LOW); 80 if (IS_ERR(dmic_en)) 81 return PTR_ERR(dmic_en); 82 83 snd_soc_codec_set_drvdata(codec, dmic_en); 84 85 return 0; 86 } 87 88 static const struct snd_soc_dapm_widget dmic_dapm_widgets[] = { 89 SND_SOC_DAPM_AIF_OUT("DMIC AIF", "Capture", 0, 90 SND_SOC_NOPM, 0, 0), 91 SND_SOC_DAPM_INPUT("DMic"), 92 }; 93 94 static const struct snd_soc_dapm_route intercon[] = { 95 {"DMIC AIF", NULL, "DMic"}, 96 }; 97 98 static const struct snd_soc_codec_driver soc_dmic = { 99 .probe = dmic_codec_probe, 100 .component_driver = { 101 .dapm_widgets = dmic_dapm_widgets, 102 .num_dapm_widgets = ARRAY_SIZE(dmic_dapm_widgets), 103 .dapm_routes = intercon, 104 .num_dapm_routes = ARRAY_SIZE(intercon), 105 }, 106 }; 107 108 static int dmic_dev_probe(struct platform_device *pdev) 109 { 110 int err; 111 u32 chans; 112 struct snd_soc_dai_driver *dai_drv = &dmic_dai; 113 114 if (pdev->dev.of_node) { 115 err = of_property_read_u32(pdev->dev.of_node, "num-channels", &chans); 116 if (err && (err != -EINVAL)) 117 return err; 118 119 if (!err) { 120 if (chans < 1 || chans > 8) 121 return -EINVAL; 122 123 dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL); 124 if (!dai_drv) 125 return -ENOMEM; 126 127 memcpy(dai_drv, &dmic_dai, sizeof(*dai_drv)); 128 dai_drv->capture.channels_max = chans; 129 } 130 } 131 132 return snd_soc_register_codec(&pdev->dev, 133 &soc_dmic, dai_drv, 1); 134 } 135 136 static int dmic_dev_remove(struct platform_device *pdev) 137 { 138 snd_soc_unregister_codec(&pdev->dev); 139 return 0; 140 } 141 142 MODULE_ALIAS("platform:dmic-codec"); 143 144 static const struct of_device_id dmic_dev_match[] = { 145 {.compatible = "dmic-codec"}, 146 {} 147 }; 148 149 static struct platform_driver dmic_driver = { 150 .driver = { 151 .name = "dmic-codec", 152 .of_match_table = dmic_dev_match, 153 }, 154 .probe = dmic_dev_probe, 155 .remove = dmic_dev_remove, 156 }; 157 158 module_platform_driver(dmic_driver); 159 160 MODULE_DESCRIPTION("Generic DMIC driver"); 161 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>"); 162 MODULE_LICENSE("GPL"); 163