1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2017 BayLibre, SAS.
4 * Author: Jerome Brunet <jbrunet@baylibre.com>
5 */
6
7 #include <linux/gpio/consumer.h>
8 #include <linux/module.h>
9 #include <linux/regulator/consumer.h>
10 #include <sound/soc.h>
11
12 #define DRV_NAME "simple-amplifier"
13
14 struct simple_amp {
15 struct gpio_desc *gpiod_enable;
16 };
17
18 static int drv_event(struct snd_soc_dapm_widget *w,
19 struct snd_kcontrol *control, int event)
20 {
21 struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
22 struct simple_amp *priv = snd_soc_component_get_drvdata(c);
23 int val;
24
25 switch (event) {
26 case SND_SOC_DAPM_POST_PMU:
27 val = 1;
28 break;
29 case SND_SOC_DAPM_PRE_PMD:
30 val = 0;
31 break;
32 default:
33 WARN(1, "Unexpected event");
34 return -EINVAL;
35 }
36
37 gpiod_set_value_cansleep(priv->gpiod_enable, val);
38
39 return 0;
40 }
41
42 static const struct snd_soc_dapm_widget simple_amp_dapm_widgets[] = {
43 SND_SOC_DAPM_INPUT("INL"),
44 SND_SOC_DAPM_INPUT("INR"),
45 SND_SOC_DAPM_OUT_DRV_E("DRV", SND_SOC_NOPM, 0, 0, NULL, 0, drv_event,
46 (SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD)),
47 SND_SOC_DAPM_OUTPUT("OUTL"),
48 SND_SOC_DAPM_OUTPUT("OUTR"),
49 SND_SOC_DAPM_REGULATOR_SUPPLY("VCC", 20, 0),
50 };
51
52 static const struct snd_soc_dapm_route simple_amp_dapm_routes[] = {
53 { "DRV", NULL, "INL" },
54 { "DRV", NULL, "INR" },
55 { "OUTL", NULL, "VCC" },
56 { "OUTR", NULL, "VCC" },
57 { "OUTL", NULL, "DRV" },
58 { "OUTR", NULL, "DRV" },
59 };
60
61 static const struct snd_soc_component_driver simple_amp_component_driver = {
62 .dapm_widgets = simple_amp_dapm_widgets,
63 .num_dapm_widgets = ARRAY_SIZE(simple_amp_dapm_widgets),
64 .dapm_routes = simple_amp_dapm_routes,
65 .num_dapm_routes = ARRAY_SIZE(simple_amp_dapm_routes),
66 };
67
68 static int simple_amp_probe(struct platform_device *pdev)
69 {
70 struct device *dev = &pdev->dev;
71 struct simple_amp *priv;
72
73 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
74 if (priv == NULL)
75 return -ENOMEM;
76 platform_set_drvdata(pdev, priv);
77
78 priv->gpiod_enable = devm_gpiod_get_optional(dev, "enable",
79 GPIOD_OUT_LOW);
80 if (IS_ERR(priv->gpiod_enable))
81 return dev_err_probe(dev, PTR_ERR(priv->gpiod_enable),
82 "Failed to get 'enable' gpio");
83
84 return devm_snd_soc_register_component(dev,
85 &simple_amp_component_driver,
86 NULL, 0);
87 }
88
89 #ifdef CONFIG_OF
90 static const struct of_device_id simple_amp_ids[] = {
91 { .compatible = "dioo,dio2125", },
92 { .compatible = "simple-audio-amplifier", },
93 { }
94 };
95 MODULE_DEVICE_TABLE(of, simple_amp_ids);
96 #endif
97
98 static struct platform_driver simple_amp_driver = {
99 .driver = {
100 .name = DRV_NAME,
101 .of_match_table = of_match_ptr(simple_amp_ids),
102 },
103 .probe = simple_amp_probe,
104 };
105
106 module_platform_driver(simple_amp_driver);
107
108 MODULE_DESCRIPTION("ASoC Simple Audio Amplifier driver");
109 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
110 MODULE_LICENSE("GPL");
111
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