Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
34static int modeswitch_delay;
35module_param(modeswitch_delay, uint, 0644);
36
37static int wakeup_delay;
38module_param(wakeup_delay, uint, 0644);
39
40struct dmic {
41 struct gpio_desc *gpio_en;
42 int wakeup_delay;
43 /* Delay after DMIC mode switch */
44 int modeswitch_delay;
45};
46
47int 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
64static const struct snd_soc_dai_ops dmic_dai_ops = {
65 .trigger = dmic_daiops_trigger,
66};
67
68static 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
90static 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
104static 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
134static 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
141static const struct snd_soc_dapm_route intercon[] = {
142 {"DMIC AIF", NULL, "DMic"},
143};
144
145static 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
157static 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
185MODULE_ALIAS("platform:dmic-codec");
186
187static const struct of_device_id dmic_dev_match[] = {
188 {.compatible = "dmic-codec"},
189 {}
190};
191MODULE_DEVICE_TABLE(of, dmic_dev_match);
192
193static 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
201module_platform_driver(dmic_driver);
202
203MODULE_DESCRIPTION("Generic DMIC driver");
204MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
205MODULE_LICENSE("GPL");