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/regulator/consumer.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <sound/core.h>
16 #include <sound/pcm.h>
17 #include <sound/soc.h>
18 #include <sound/soc-dapm.h>
19
20 #define MAX_MODESWITCH_DELAY 70
21 static int modeswitch_delay;
22 module_param(modeswitch_delay, uint, 0644);
23
24 static int wakeup_delay;
25 module_param(wakeup_delay, uint, 0644);
26
27 struct dmic {
28 struct gpio_desc *gpio_en;
29 struct regulator *vref;
30 int wakeup_delay;
31 /* Delay after DMIC mode switch */
32 int modeswitch_delay;
33 };
34
dmic_daiops_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * dai)35 static int dmic_daiops_trigger(struct snd_pcm_substream *substream,
36 int cmd, struct snd_soc_dai *dai)
37 {
38 struct snd_soc_component *component = dai->component;
39 struct dmic *dmic = snd_soc_component_get_drvdata(component);
40
41 switch (cmd) {
42 case SNDRV_PCM_TRIGGER_STOP:
43 if (dmic->modeswitch_delay)
44 mdelay(dmic->modeswitch_delay);
45
46 break;
47 }
48
49 return 0;
50 }
51
52 static const struct snd_soc_dai_ops dmic_dai_ops = {
53 .trigger = dmic_daiops_trigger,
54 };
55
dmic_aif_event(struct snd_soc_dapm_widget * w,struct snd_kcontrol * kcontrol,int event)56 static int dmic_aif_event(struct snd_soc_dapm_widget *w,
57 struct snd_kcontrol *kcontrol, int event) {
58 struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
59 struct dmic *dmic = snd_soc_component_get_drvdata(component);
60 int ret = 0;
61
62 switch (event) {
63 case SND_SOC_DAPM_POST_PMU:
64 if (dmic->gpio_en)
65 gpiod_set_value_cansleep(dmic->gpio_en, 1);
66
67 if (dmic->vref) {
68 ret = regulator_enable(dmic->vref);
69 if (ret)
70 return ret;
71 }
72
73 if (dmic->wakeup_delay)
74 msleep(dmic->wakeup_delay);
75 break;
76 case SND_SOC_DAPM_POST_PMD:
77 if (dmic->gpio_en)
78 gpiod_set_value_cansleep(dmic->gpio_en, 0);
79
80 if (dmic->vref)
81 ret = regulator_disable(dmic->vref);
82
83 break;
84 }
85
86 return ret;
87 }
88
89 static struct snd_soc_dai_driver dmic_dai = {
90 .name = "dmic-hifi",
91 .capture = {
92 .stream_name = "Capture",
93 .channels_min = 1,
94 .channels_max = 8,
95 .rates = SNDRV_PCM_RATE_CONTINUOUS,
96 .formats = SNDRV_PCM_FMTBIT_S32_LE
97 | SNDRV_PCM_FMTBIT_S24_LE
98 | SNDRV_PCM_FMTBIT_S16_LE
99 | SNDRV_PCM_FMTBIT_DSD_U8
100 | SNDRV_PCM_FMTBIT_DSD_U16_LE
101 | SNDRV_PCM_FMTBIT_DSD_U32_LE
102 | SNDRV_PCM_FMTBIT_DSD_U16_BE
103 | SNDRV_PCM_FMTBIT_DSD_U32_BE,
104 },
105 .ops = &dmic_dai_ops,
106 };
107
dmic_component_probe(struct snd_soc_component * component)108 static int dmic_component_probe(struct snd_soc_component *component)
109 {
110 struct dmic *dmic;
111
112 dmic = devm_kzalloc(component->dev, sizeof(*dmic), GFP_KERNEL);
113 if (!dmic)
114 return -ENOMEM;
115
116 dmic->vref = devm_regulator_get_optional(component->dev, "vref");
117 if (IS_ERR(dmic->vref)) {
118 if (PTR_ERR(dmic->vref) != -ENODEV)
119 return dev_err_probe(component->dev, PTR_ERR(dmic->vref),
120 "Failed to get vref\n");
121 dmic->vref = NULL;
122 }
123
124 dmic->gpio_en = devm_gpiod_get_optional(component->dev,
125 "dmicen", GPIOD_OUT_LOW);
126 if (IS_ERR(dmic->gpio_en))
127 return PTR_ERR(dmic->gpio_en);
128
129 device_property_read_u32(component->dev, "wakeup-delay-ms",
130 &dmic->wakeup_delay);
131 device_property_read_u32(component->dev, "modeswitch-delay-ms",
132 &dmic->modeswitch_delay);
133 if (wakeup_delay)
134 dmic->wakeup_delay = wakeup_delay;
135 if (modeswitch_delay)
136 dmic->modeswitch_delay = modeswitch_delay;
137
138 if (dmic->modeswitch_delay > MAX_MODESWITCH_DELAY)
139 dmic->modeswitch_delay = MAX_MODESWITCH_DELAY;
140
141 snd_soc_component_set_drvdata(component, dmic);
142
143 return 0;
144 }
145
146 static const struct snd_soc_dapm_widget dmic_dapm_widgets[] = {
147 SND_SOC_DAPM_AIF_OUT_E("DMIC AIF", "Capture", 0,
148 SND_SOC_NOPM, 0, 0, dmic_aif_event,
149 SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD),
150 SND_SOC_DAPM_INPUT("DMic"),
151 };
152
153 static const struct snd_soc_dapm_route intercon[] = {
154 {"DMIC AIF", NULL, "DMic"},
155 };
156
157 static const struct snd_soc_component_driver soc_dmic = {
158 .probe = dmic_component_probe,
159 .dapm_widgets = dmic_dapm_widgets,
160 .num_dapm_widgets = ARRAY_SIZE(dmic_dapm_widgets),
161 .dapm_routes = intercon,
162 .num_dapm_routes = ARRAY_SIZE(intercon),
163 .idle_bias_on = 1,
164 .use_pmdown_time = 1,
165 .endianness = 1,
166 };
167
dmic_dev_probe(struct platform_device * pdev)168 static int dmic_dev_probe(struct platform_device *pdev)
169 {
170 int err;
171 u32 chans;
172 struct snd_soc_dai_driver *dai_drv = &dmic_dai;
173
174 if (pdev->dev.of_node) {
175 err = of_property_read_u32(pdev->dev.of_node, "num-channels", &chans);
176 if (err && (err != -EINVAL))
177 return err;
178
179 if (!err) {
180 if (chans < 1 || chans > 8)
181 return -EINVAL;
182
183 dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL);
184 if (!dai_drv)
185 return -ENOMEM;
186
187 memcpy(dai_drv, &dmic_dai, sizeof(*dai_drv));
188 dai_drv->capture.channels_max = chans;
189 }
190 }
191
192 return devm_snd_soc_register_component(&pdev->dev,
193 &soc_dmic, dai_drv, 1);
194 }
195
196 MODULE_ALIAS("platform:dmic-codec");
197
198 static const struct of_device_id dmic_dev_match[] = {
199 {.compatible = "dmic-codec"},
200 {}
201 };
202 MODULE_DEVICE_TABLE(of, dmic_dev_match);
203
204 static struct platform_driver dmic_driver = {
205 .driver = {
206 .name = "dmic-codec",
207 .of_match_table = dmic_dev_match,
208 },
209 .probe = dmic_dev_probe,
210 };
211
212 module_platform_driver(dmic_driver);
213
214 MODULE_DESCRIPTION("Generic DMIC driver");
215 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
216 MODULE_LICENSE("GPL");
217