@@ -6,6 +6,7 @@
#include <linux/gpio/consumer.h>
#include <linux/module.h>
+#include <linux/mux/driver.h>
#include <linux/regulator/consumer.h>
#include <sound/soc.h>
@@ -16,6 +17,7 @@ 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];
@@ -57,6 +59,9 @@ static int simple_mux_control_put(struct snd_kcontrol *kcontrol,
priv->mux = ucontrol->value.enumerated.item[0];
+ if (priv->idle_state != MUX_IDLE_AS_IS && dapm->bias_level < SND_SOC_BIAS_PREPARE)
+ return 0;
+
gpiod_set_value_cansleep(priv->gpiod_mux, priv->mux);
return snd_soc_dapm_mux_update_power(dapm, kcontrol,
@@ -75,10 +80,33 @@ static unsigned int simple_mux_read(struct snd_soc_component *component,
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("MUX", SND_SOC_NOPM, 0, 0, &simple_mux_mux), // see simple_mux_probe()
+ SND_SOC_DAPM_MUX_E("MUX", SND_SOC_NOPM, 0, 0, &simple_mux_mux, // see simple_mux_probe()
+ simple_mux_event, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
SND_SOC_DAPM_OUTPUT("OUT"),
};
@@ -93,6 +121,7 @@ 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)
@@ -121,6 +150,14 @@ static int simple_mux_probe(struct platform_device *pdev)
/* Overwrite text ("Input 1", "Input 2") if property exists */
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;
+ }
+
/* switch to use priv data instead of default */
priv->mux_enum.texts = priv->mux_texts;
priv->mux_mux.private_value = (unsigned long)&priv->mux_enum;
So far the mux changes it state immediately, even when not in use. Allow overriding this behaviour by specifying an optional idle-state. This state is used whenever the mux is powered down, only switching to the selected state on power up. If unspecified it defaults to as-is, maintaining the previous behaviour. Signed-off-by: Hendrik v. Raven <h.v.raven@merzmedtech.de> --- Changes in v2: - fix nullpointer dereference in simple_mux_event --- sound/soc/codecs/simple-mux.c | 39 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-)