linux/sound/soc/codecs/aw8738.c
Jonathan Albrieux 6b4528b553
ASoC: codecs: Add Awinic AW8738 audio amplifier driver
The Awinic AW8738 is a simple audio amplifier using a single GPIO.
The main difference to simple-amplifier is that there is a "one-wire
pulse control" that allows configuring the amplifier to one of a few
pre-defined modes. This can be used to configure the speaker-guard
function (primarily the power limit for the amplifier).

Add a simple driver that allows setting it up in the device tree
with a specified mode number.

Signed-off-by: Jonathan Albrieux <jonathan.albrieux@gmail.com>
Co-developed-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20220304102452.26856-3-stephan@gerhold.net
Signed-off-by: Mark Brown <broonie@kernel.org>
2022-03-07 13:13:01 +00:00

105 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
#include <sound/soc.h>
struct aw8738_priv {
struct gpio_desc *gpiod_mode;
unsigned int mode;
};
static int aw8738_drv_event(struct snd_soc_dapm_widget *w,
struct snd_kcontrol *kcontrol, int event)
{
struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
struct aw8738_priv *aw = snd_soc_component_get_drvdata(c);
int i;
switch (event) {
case SND_SOC_DAPM_POST_PMU:
for (i = 0; i < aw->mode; i++) {
gpiod_set_value_cansleep(aw->gpiod_mode, 0);
udelay(2);
gpiod_set_value_cansleep(aw->gpiod_mode, 1);
udelay(2);
}
msleep(40);
break;
case SND_SOC_DAPM_PRE_PMD:
gpiod_set_value_cansleep(aw->gpiod_mode, 0);
usleep_range(1000, 2000);
break;
default:
WARN(1, "Unexpected event");
return -EINVAL;
}
return 0;
}
static const struct snd_soc_dapm_widget aw8738_dapm_widgets[] = {
SND_SOC_DAPM_INPUT("IN"),
SND_SOC_DAPM_OUT_DRV_E("DRV", SND_SOC_NOPM, 0, 0, NULL, 0, aw8738_drv_event,
SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
SND_SOC_DAPM_OUTPUT("OUT"),
};
static const struct snd_soc_dapm_route aw8738_dapm_routes[] = {
{ "DRV", NULL, "IN" },
{ "OUT", NULL, "DRV" },
};
static const struct snd_soc_component_driver aw8738_component_driver = {
.dapm_widgets = aw8738_dapm_widgets,
.num_dapm_widgets = ARRAY_SIZE(aw8738_dapm_widgets),
.dapm_routes = aw8738_dapm_routes,
.num_dapm_routes = ARRAY_SIZE(aw8738_dapm_routes),
};
static int aw8738_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct aw8738_priv *aw;
int ret;
aw = devm_kzalloc(dev, sizeof(*aw), GFP_KERNEL);
if (!aw)
return -ENOMEM;
platform_set_drvdata(pdev, aw);
aw->gpiod_mode = devm_gpiod_get(dev, "mode", GPIOD_OUT_LOW);
if (IS_ERR(aw->gpiod_mode))
return dev_err_probe(dev, PTR_ERR(aw->gpiod_mode),
"Failed to get 'mode' gpio");
ret = device_property_read_u32(dev, "awinic,mode", &aw->mode);
if (ret)
return -EINVAL;
return devm_snd_soc_register_component(&pdev->dev,
&aw8738_component_driver,
NULL, 0);
}
#ifdef CONFIG_OF
static const struct of_device_id aw8738_of_match[] = {
{ .compatible = "awinic,aw8738" },
{ }
};
MODULE_DEVICE_TABLE(of, aw8738_of_match);
#endif
static struct platform_driver aw8738_driver = {
.probe = aw8738_probe,
.driver = {
.name = "aw8738",
.of_match_table = of_match_ptr(aw8738_of_match),
},
};
module_platform_driver(aw8738_driver);
MODULE_DESCRIPTION("Awinic AW8738 Amplifier Driver");
MODULE_LICENSE("GPL v2");