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 struct dmic { 34 struct gpio_desc *gpio_en; 35 int wakeup_delay; 36 }; 37 38 static int dmic_aif_event(struct snd_soc_dapm_widget *w, 39 struct snd_kcontrol *kcontrol, int event) { 40 struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm); 41 struct dmic *dmic = snd_soc_component_get_drvdata(component); 42 43 switch (event) { 44 case SND_SOC_DAPM_POST_PMU: 45 if (dmic->gpio_en) 46 gpiod_set_value(dmic->gpio_en, 1); 47 48 if (dmic->wakeup_delay) 49 msleep(dmic->wakeup_delay); 50 break; 51 case SND_SOC_DAPM_POST_PMD: 52 if (dmic->gpio_en) 53 gpiod_set_value(dmic->gpio_en, 0); 54 break; 55 } 56 57 return 0; 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 }; 72 73 static int dmic_component_probe(struct snd_soc_component *component) 74 { 75 struct dmic *dmic; 76 77 dmic = devm_kzalloc(component->dev, sizeof(*dmic), GFP_KERNEL); 78 if (!dmic) 79 return -ENOMEM; 80 81 dmic->gpio_en = devm_gpiod_get_optional(component->dev, 82 "dmicen", GPIOD_OUT_LOW); 83 if (IS_ERR(dmic->gpio_en)) 84 return PTR_ERR(dmic->gpio_en); 85 86 device_property_read_u32(component->dev, "wakeup-delay-ms", 87 &dmic->wakeup_delay); 88 89 snd_soc_component_set_drvdata(component, dmic); 90 91 return 0; 92 } 93 94 static const struct snd_soc_dapm_widget dmic_dapm_widgets[] = { 95 SND_SOC_DAPM_AIF_OUT_E("DMIC AIF", "Capture", 0, 96 SND_SOC_NOPM, 0, 0, dmic_aif_event, 97 SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD), 98 SND_SOC_DAPM_INPUT("DMic"), 99 }; 100 101 static const struct snd_soc_dapm_route intercon[] = { 102 {"DMIC AIF", NULL, "DMic"}, 103 }; 104 105 static const struct snd_soc_component_driver soc_dmic = { 106 .probe = dmic_component_probe, 107 .dapm_widgets = dmic_dapm_widgets, 108 .num_dapm_widgets = ARRAY_SIZE(dmic_dapm_widgets), 109 .dapm_routes = intercon, 110 .num_dapm_routes = ARRAY_SIZE(intercon), 111 .idle_bias_on = 1, 112 .use_pmdown_time = 1, 113 .endianness = 1, 114 .non_legacy_dai_naming = 1, 115 }; 116 117 static int dmic_dev_probe(struct platform_device *pdev) 118 { 119 int err; 120 u32 chans; 121 struct snd_soc_dai_driver *dai_drv = &dmic_dai; 122 123 if (pdev->dev.of_node) { 124 err = of_property_read_u32(pdev->dev.of_node, "num-channels", &chans); 125 if (err && (err != -EINVAL)) 126 return err; 127 128 if (!err) { 129 if (chans < 1 || chans > 8) 130 return -EINVAL; 131 132 dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL); 133 if (!dai_drv) 134 return -ENOMEM; 135 136 memcpy(dai_drv, &dmic_dai, sizeof(*dai_drv)); 137 dai_drv->capture.channels_max = chans; 138 } 139 } 140 141 return devm_snd_soc_register_component(&pdev->dev, 142 &soc_dmic, dai_drv, 1); 143 } 144 145 MODULE_ALIAS("platform:dmic-codec"); 146 147 static const struct of_device_id dmic_dev_match[] = { 148 {.compatible = "dmic-codec"}, 149 {} 150 }; 151 152 static struct platform_driver dmic_driver = { 153 .driver = { 154 .name = "dmic-codec", 155 .of_match_table = dmic_dev_match, 156 }, 157 .probe = dmic_dev_probe, 158 }; 159 160 module_platform_driver(dmic_driver); 161 162 MODULE_DESCRIPTION("Generic DMIC driver"); 163 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>"); 164 MODULE_LICENSE("GPL"); 165