1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (c) 2020 Bootlin SA |
4 | * Author: Alexandre Belloni <alexandre.belloni@bootlin.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 | struct simple_mux { |
13 | struct gpio_desc *gpiod_mux; |
14 | unsigned int mux; |
15 | }; |
16 | |
17 | static const char * const simple_mux_texts[] = { |
18 | "Input 1" , "Input 2" |
19 | }; |
20 | |
21 | static SOC_ENUM_SINGLE_EXT_DECL(simple_mux_enum, simple_mux_texts); |
22 | |
23 | static 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 | |
35 | static 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(desc: priv->gpiod_mux, value: priv->mux); |
52 | |
53 | return snd_soc_dapm_mux_update_power(dapm, kcontrol, |
54 | mux: ucontrol->value.enumerated.item[0], |
55 | e, NULL); |
56 | } |
57 | |
58 | static unsigned int simple_mux_read(struct snd_soc_component *component, |
59 | unsigned int reg) |
60 | { |
61 | struct simple_mux *priv = snd_soc_component_get_drvdata(c: component); |
62 | |
63 | return priv->mux; |
64 | } |
65 | |
66 | static const struct snd_kcontrol_new simple_mux_mux = |
67 | SOC_DAPM_ENUM_EXT("Muxer" , simple_mux_enum, simple_mux_control_get, simple_mux_control_put); |
68 | |
69 | static const struct snd_soc_dapm_widget simple_mux_dapm_widgets[] = { |
70 | SND_SOC_DAPM_INPUT("IN1" ), |
71 | SND_SOC_DAPM_INPUT("IN2" ), |
72 | SND_SOC_DAPM_MUX("MUX" , SND_SOC_NOPM, 0, 0, &simple_mux_mux), |
73 | SND_SOC_DAPM_OUTPUT("OUT" ), |
74 | }; |
75 | |
76 | static const struct snd_soc_dapm_route simple_mux_dapm_routes[] = { |
77 | { "OUT" , NULL, "MUX" }, |
78 | { "MUX" , "Input 1" , "IN1" }, |
79 | { "MUX" , "Input 2" , "IN2" }, |
80 | }; |
81 | |
82 | static const struct snd_soc_component_driver simple_mux_component_driver = { |
83 | .dapm_widgets = simple_mux_dapm_widgets, |
84 | .num_dapm_widgets = ARRAY_SIZE(simple_mux_dapm_widgets), |
85 | .dapm_routes = simple_mux_dapm_routes, |
86 | .num_dapm_routes = ARRAY_SIZE(simple_mux_dapm_routes), |
87 | .read = simple_mux_read, |
88 | }; |
89 | |
90 | static int simple_mux_probe(struct platform_device *pdev) |
91 | { |
92 | struct device *dev = &pdev->dev; |
93 | struct simple_mux *priv; |
94 | |
95 | priv = devm_kzalloc(dev, size: sizeof(*priv), GFP_KERNEL); |
96 | if (!priv) |
97 | return -ENOMEM; |
98 | |
99 | dev_set_drvdata(dev, data: priv); |
100 | |
101 | priv->gpiod_mux = devm_gpiod_get(dev, con_id: "mux" , flags: GPIOD_OUT_LOW); |
102 | if (IS_ERR(ptr: priv->gpiod_mux)) |
103 | return dev_err_probe(dev, err: PTR_ERR(ptr: priv->gpiod_mux), |
104 | fmt: "Failed to get 'mux' gpio" ); |
105 | |
106 | return devm_snd_soc_register_component(dev, component_driver: &simple_mux_component_driver, NULL, num_dai: 0); |
107 | } |
108 | |
109 | #ifdef CONFIG_OF |
110 | static const struct of_device_id simple_mux_ids[] = { |
111 | { .compatible = "simple-audio-mux" , }, |
112 | { } |
113 | }; |
114 | MODULE_DEVICE_TABLE(of, simple_mux_ids); |
115 | #endif |
116 | |
117 | static struct platform_driver simple_mux_driver = { |
118 | .driver = { |
119 | .name = "simple-mux" , |
120 | .of_match_table = of_match_ptr(simple_mux_ids), |
121 | }, |
122 | .probe = simple_mux_probe, |
123 | }; |
124 | |
125 | module_platform_driver(simple_mux_driver); |
126 | |
127 | MODULE_DESCRIPTION("ASoC Simple Audio Mux driver" ); |
128 | MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>" ); |
129 | MODULE_LICENSE("GPL" ); |
130 | |