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
20static int modeswitch_delay;
21module_param(modeswitch_delay, uint, 0644);
22
23static int wakeup_delay;
24module_param(wakeup_delay, uint, 0644);
25
26struct dmic {
27	struct gpio_desc *gpio_en;
28	int wakeup_delay;
29	/* Delay after DMIC mode switch */
30	int modeswitch_delay;
31};
32
33static 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
50static const struct snd_soc_dai_ops dmic_dai_ops = {
51	.trigger	= dmic_daiops_trigger,
52};
53
54static 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
76static 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
93static 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
123static 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
130static const struct snd_soc_dapm_route intercon[] = {
131	{"DMIC AIF", NULL, "DMic"},
132};
133
134static 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
145static 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
173MODULE_ALIAS("platform:dmic-codec");
174
175static const struct of_device_id dmic_dev_match[] = {
176	{.compatible = "dmic-codec"},
177	{}
178};
179MODULE_DEVICE_TABLE(of, dmic_dev_match);
180
181static 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
189module_platform_driver(dmic_driver);
190
191MODULE_DESCRIPTION("Generic DMIC driver");
192MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
193MODULE_LICENSE("GPL");
194