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