xref: /openbmc/linux/sound/soc/codecs/dmic.c (revision e65e175b)
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_cansleep(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_cansleep(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 			| SNDRV_PCM_FMTBIT_DSD_U8
87 			| SNDRV_PCM_FMTBIT_DSD_U16_LE
88 			| SNDRV_PCM_FMTBIT_DSD_U32_LE,
89 	},
90 	.ops    = &dmic_dai_ops,
91 };
92 
93 static int dmic_component_probe(struct snd_soc_component *component)
94 {
95 	struct dmic *dmic;
96 
97 	dmic = devm_kzalloc(component->dev, sizeof(*dmic), GFP_KERNEL);
98 	if (!dmic)
99 		return -ENOMEM;
100 
101 	dmic->gpio_en = devm_gpiod_get_optional(component->dev,
102 						"dmicen", GPIOD_OUT_LOW);
103 	if (IS_ERR(dmic->gpio_en))
104 		return PTR_ERR(dmic->gpio_en);
105 
106 	device_property_read_u32(component->dev, "wakeup-delay-ms",
107 				 &dmic->wakeup_delay);
108 	device_property_read_u32(component->dev, "modeswitch-delay-ms",
109 				 &dmic->modeswitch_delay);
110 	if (wakeup_delay)
111 		dmic->wakeup_delay  = wakeup_delay;
112 	if (modeswitch_delay)
113 		dmic->modeswitch_delay  = modeswitch_delay;
114 
115 	if (dmic->modeswitch_delay > MAX_MODESWITCH_DELAY)
116 		dmic->modeswitch_delay = MAX_MODESWITCH_DELAY;
117 
118 	snd_soc_component_set_drvdata(component, dmic);
119 
120 	return 0;
121 }
122 
123 static const struct snd_soc_dapm_widget dmic_dapm_widgets[] = {
124 	SND_SOC_DAPM_AIF_OUT_E("DMIC AIF", "Capture", 0,
125 			       SND_SOC_NOPM, 0, 0, dmic_aif_event,
126 			       SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD),
127 	SND_SOC_DAPM_INPUT("DMic"),
128 };
129 
130 static const struct snd_soc_dapm_route intercon[] = {
131 	{"DMIC AIF", NULL, "DMic"},
132 };
133 
134 static const struct snd_soc_component_driver soc_dmic = {
135 	.probe			= dmic_component_probe,
136 	.dapm_widgets		= dmic_dapm_widgets,
137 	.num_dapm_widgets	= ARRAY_SIZE(dmic_dapm_widgets),
138 	.dapm_routes		= intercon,
139 	.num_dapm_routes	= ARRAY_SIZE(intercon),
140 	.idle_bias_on		= 1,
141 	.use_pmdown_time	= 1,
142 	.endianness		= 1,
143 };
144 
145 static int dmic_dev_probe(struct platform_device *pdev)
146 {
147 	int err;
148 	u32 chans;
149 	struct snd_soc_dai_driver *dai_drv = &dmic_dai;
150 
151 	if (pdev->dev.of_node) {
152 		err = of_property_read_u32(pdev->dev.of_node, "num-channels", &chans);
153 		if (err && (err != -EINVAL))
154 			return err;
155 
156 		if (!err) {
157 			if (chans < 1 || chans > 8)
158 				return -EINVAL;
159 
160 			dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL);
161 			if (!dai_drv)
162 				return -ENOMEM;
163 
164 			memcpy(dai_drv, &dmic_dai, sizeof(*dai_drv));
165 			dai_drv->capture.channels_max = chans;
166 		}
167 	}
168 
169 	return devm_snd_soc_register_component(&pdev->dev,
170 			&soc_dmic, dai_drv, 1);
171 }
172 
173 MODULE_ALIAS("platform:dmic-codec");
174 
175 static const struct of_device_id dmic_dev_match[] = {
176 	{.compatible = "dmic-codec"},
177 	{}
178 };
179 MODULE_DEVICE_TABLE(of, dmic_dev_match);
180 
181 static struct platform_driver dmic_driver = {
182 	.driver = {
183 		.name = "dmic-codec",
184 		.of_match_table = dmic_dev_match,
185 	},
186 	.probe = dmic_dev_probe,
187 };
188 
189 module_platform_driver(dmic_driver);
190 
191 MODULE_DESCRIPTION("Generic DMIC driver");
192 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
193 MODULE_LICENSE("GPL");
194