xref: /openbmc/linux/sound/soc/codecs/dmic.c (revision be709d48)
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");
206