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7#include <linux/gpio/consumer.h>
8#include <linux/module.h>
9#include <linux/regulator/consumer.h>
10#include <sound/soc.h>
11
12struct simple_mux {
13 struct gpio_desc *gpiod_mux;
14 unsigned int mux;
15};
16
17static const char * const simple_mux_texts[] = {
18 "Input 1", "Input 2"
19};
20
21static SOC_ENUM_SINGLE_EXT_DECL(simple_mux_enum, simple_mux_texts);
22
23static int simple_mux_control_get(struct snd_kcontrol *kcontrol,
24 struct snd_ctl_elem_value *ucontrol)
25{
26 struct snd_soc_dapm_context *dapm = snd_soc_dapm_kcontrol_dapm(kcontrol);
27 struct snd_soc_component *c = snd_soc_dapm_to_component(dapm);
28 struct simple_mux *priv = snd_soc_component_get_drvdata(c);
29
30 ucontrol->value.enumerated.item[0] = priv->mux;
31
32 return 0;
33}
34
35static int simple_mux_control_put(struct snd_kcontrol *kcontrol,
36 struct snd_ctl_elem_value *ucontrol)
37{
38 struct snd_soc_dapm_context *dapm = snd_soc_dapm_kcontrol_dapm(kcontrol);
39 struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
40 struct snd_soc_component *c = snd_soc_dapm_to_component(dapm);
41 struct simple_mux *priv = snd_soc_component_get_drvdata(c);
42
43 if (ucontrol->value.enumerated.item[0] > e->items)
44 return -EINVAL;
45
46 if (priv->mux == ucontrol->value.enumerated.item[0])
47 return 0;
48
49 priv->mux = ucontrol->value.enumerated.item[0];
50
51 gpiod_set_value_cansleep(priv->gpiod_mux, priv->mux);
52
53 return snd_soc_dapm_mux_update_power(dapm, kcontrol,
54 ucontrol->value.enumerated.item[0],
55 e, NULL);
56}
57
58static const struct snd_kcontrol_new simple_mux_mux =
59 SOC_DAPM_ENUM_EXT("Muxer", simple_mux_enum, simple_mux_control_get, simple_mux_control_put);
60
61static const struct snd_soc_dapm_widget simple_mux_dapm_widgets[] = {
62 SND_SOC_DAPM_INPUT("IN1"),
63 SND_SOC_DAPM_INPUT("IN2"),
64 SND_SOC_DAPM_MUX("MUX", SND_SOC_NOPM, 0, 0, &simple_mux_mux),
65 SND_SOC_DAPM_OUTPUT("OUT"),
66};
67
68static const struct snd_soc_dapm_route simple_mux_dapm_routes[] = {
69 { "OUT", NULL, "MUX" },
70 { "MUX", "Input 1", "IN1" },
71 { "MUX", "Input 2", "IN2" },
72};
73
74static const struct snd_soc_component_driver simple_mux_component_driver = {
75 .dapm_widgets = simple_mux_dapm_widgets,
76 .num_dapm_widgets = ARRAY_SIZE(simple_mux_dapm_widgets),
77 .dapm_routes = simple_mux_dapm_routes,
78 .num_dapm_routes = ARRAY_SIZE(simple_mux_dapm_routes),
79};
80
81static int simple_mux_probe(struct platform_device *pdev)
82{
83 struct device *dev = &pdev->dev;
84 struct simple_mux *priv;
85 int err;
86
87 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
88 if (!priv)
89 return -ENOMEM;
90
91 dev_set_drvdata(dev, priv);
92
93 priv->gpiod_mux = devm_gpiod_get(dev, "mux", GPIOD_OUT_LOW);
94 if (IS_ERR(priv->gpiod_mux)) {
95 err = PTR_ERR(priv->gpiod_mux);
96 if (err != -EPROBE_DEFER)
97 dev_err(dev, "Failed to get 'mux' gpio: %d", err);
98 return err;
99 }
100
101 return devm_snd_soc_register_component(dev, &simple_mux_component_driver, NULL, 0);
102}
103
104#ifdef CONFIG_OF
105static const struct of_device_id simple_mux_ids[] = {
106 { .compatible = "simple-audio-mux", },
107 { }
108};
109MODULE_DEVICE_TABLE(of, simple_mux_ids);
110#endif
111
112static struct platform_driver simple_mux_driver = {
113 .driver = {
114 .name = "simple-mux",
115 .of_match_table = of_match_ptr(simple_mux_ids),
116 },
117 .probe = simple_mux_probe,
118};
119
120module_platform_driver(simple_mux_driver);
121
122MODULE_DESCRIPTION("ASoC Simple Audio Mux driver");
123MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
124MODULE_LICENSE("GPL");
125
