#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/mux/driver.h>
#include <linux/regulator/consumer.h>
#include <sound/soc.h>
#define MUX_TEXT_SIZE 2
#define MUX_WIDGET_SIZE 4
#define MUX_ROUTE_SIZE 3
struct simple_mux {
struct gpio_desc *gpiod_mux;
unsigned int mux;
const char *mux_texts[MUX_TEXT_SIZE];
unsigned int idle_state;
struct soc_enum mux_enum;
struct snd_kcontrol_new mux_mux;
struct snd_soc_dapm_widget mux_widgets[MUX_WIDGET_SIZE];
struct snd_soc_dapm_route mux_routes[MUX_ROUTE_SIZE];
struct snd_soc_component_driver mux_driver;
};
static const char * const simple_mux_texts[MUX_TEXT_SIZE] = {
"Input 1", "Input 2"
};
static SOC_ENUM_SINGLE_EXT_DECL(simple_mux_enum, simple_mux_texts);
static int simple_mux_control_get(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct snd_soc_dapm_context *dapm = snd_soc_dapm_kcontrol_to_dapm(kcontrol);
struct snd_soc_component *c = snd_soc_dapm_to_component(dapm);
struct simple_mux *priv = snd_soc_component_get_drvdata(c);
ucontrol->value.enumerated.item[0] = priv->mux;
return 0;
}
static int simple_mux_control_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct snd_soc_dapm_context *dapm = snd_soc_dapm_kcontrol_to_dapm(kcontrol);
struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
struct snd_soc_component *c = snd_soc_dapm_to_component(dapm);
struct simple_mux *priv = snd_soc_component_get_drvdata(c);
if (ucontrol->value.enumerated.item[0] > e->items)
return -EINVAL;
if (priv->mux == ucontrol->value.enumerated.item[0])
return 0;
priv->mux = ucontrol->value.enumerated.item[0];
if (priv->idle_state != MUX_IDLE_AS_IS &&
snd_soc_dapm_get_bias_level(dapm) < SND_SOC_BIAS_PREPARE)
return 0;
gpiod_set_value_cansleep(priv->gpiod_mux, priv->mux);
return snd_soc_dapm_mux_update_power(dapm, kcontrol,
ucontrol->value.enumerated.item[0],
e, NULL);
}
static unsigned int simple_mux_read(struct snd_soc_component *component,
unsigned int reg)
{
struct simple_mux *priv = snd_soc_component_get_drvdata(component);
return priv->mux;
}
static const struct snd_kcontrol_new simple_mux_mux =
SOC_DAPM_ENUM_EXT("Muxer", simple_mux_enum, simple_mux_control_get, simple_mux_control_put);
static int simple_mux_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 simple_mux *priv = snd_soc_component_get_drvdata(c);
if (priv->idle_state != MUX_IDLE_AS_IS) {
switch (event) {
case SND_SOC_DAPM_PRE_PMU:
gpiod_set_value_cansleep(priv->gpiod_mux, priv->mux);
break;
case SND_SOC_DAPM_POST_PMD:
gpiod_set_value_cansleep(priv->gpiod_mux, priv->idle_state);
break;
default:
break;
}
}
return 0;
}
static const struct snd_soc_dapm_widget simple_mux_dapm_widgets[MUX_WIDGET_SIZE] = {
SND_SOC_DAPM_INPUT("IN1"),
SND_SOC_DAPM_INPUT("IN2"),
SND_SOC_DAPM_MUX_E("MUX", SND_SOC_NOPM, 0, 0, &simple_mux_mux,
simple_mux_event, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
SND_SOC_DAPM_OUTPUT("OUT"),
};
static const struct snd_soc_dapm_route simple_mux_dapm_routes[MUX_ROUTE_SIZE] = {
{ "OUT", NULL, "MUX" },
{ "MUX", "Input 1", "IN1" },
{ "MUX", "Input 2", "IN2" },
};
static int simple_mux_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct simple_mux *priv;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
dev_set_drvdata(dev, priv);
priv->gpiod_mux = devm_gpiod_get(dev, "mux", GPIOD_OUT_LOW);
if (IS_ERR(priv->gpiod_mux))
return dev_err_probe(dev, PTR_ERR(priv->gpiod_mux),
"Failed to get 'mux' gpio");
memcpy(&priv->mux_texts, &simple_mux_texts, sizeof(priv->mux_texts));
memcpy(&priv->mux_enum, &simple_mux_enum, sizeof(priv->mux_enum));
memcpy(&priv->mux_mux, &simple_mux_mux, sizeof(priv->mux_mux));
memcpy(&priv->mux_widgets, &simple_mux_dapm_widgets, sizeof(priv->mux_widgets));
memcpy(&priv->mux_routes, &simple_mux_dapm_routes, sizeof(priv->mux_routes));
priv->mux_driver.dapm_widgets = priv->mux_widgets;
priv->mux_driver.num_dapm_widgets = MUX_WIDGET_SIZE;
priv->mux_driver.dapm_routes = priv->mux_routes;
priv->mux_driver.num_dapm_routes = MUX_ROUTE_SIZE;
priv->mux_driver.read = simple_mux_read;
of_property_read_string_array(np, "state-labels", priv->mux_texts, MUX_TEXT_SIZE);
ret = of_property_read_u32(np, "idle-state", &priv->idle_state);
if (ret < 0) {
priv->idle_state = MUX_IDLE_AS_IS;
} else if (priv->idle_state != MUX_IDLE_AS_IS && priv->idle_state >= 2) {
dev_err(dev, "invalid idle-state %u\n", priv->idle_state);
return -EINVAL;
}
priv->mux_enum.texts = priv->mux_texts;
priv->mux_mux.private_value = (unsigned long)&priv->mux_enum;
priv->mux_widgets[2].kcontrol_news = &priv->mux_mux;
priv->mux_routes[1].control = priv->mux_texts[0];
priv->mux_routes[2].control = priv->mux_texts[1];
return devm_snd_soc_register_component(dev, &priv->mux_driver, NULL, 0);
}
#ifdef CONFIG_OF
static const struct of_device_id simple_mux_ids[] = {
{ .compatible = "simple-audio-mux", },
{ }
};
MODULE_DEVICE_TABLE(of, simple_mux_ids);
#endif
static struct platform_driver simple_mux_driver = {
.driver = {
.name = "simple-mux",
.of_match_table = of_match_ptr(simple_mux_ids),
},
.probe = simple_mux_probe,
};
module_platform_driver(simple_mux_driver);
MODULE_DESCRIPTION("ASoC Simple Audio Mux driver");
MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
MODULE_LICENSE("GPL");
