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
 14struct simple_amp {
 15	struct gpio_desc *gpiod_enable;
 16};
 17
 18static 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
 42static 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
 52static 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
 61static 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
 68static 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
 90static const struct of_device_id simple_amp_ids[] = {
 91	{ .compatible = "dioo,dio2125", },
 92	{ .compatible = "simple-audio-amplifier", },
 93	{ }
 94};
 95MODULE_DEVICE_TABLE(of, simple_amp_ids);
 96#endif
 97
 98static 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
106module_platform_driver(simple_amp_driver);
107
108MODULE_DESCRIPTION("ASoC Simple Audio Amplifier driver");
109MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
110MODULE_LICENSE("GPL");