diff options
Diffstat (limited to 'sound/soc/codecs/simple-mux.c')
| -rw-r--r-- | sound/soc/codecs/simple-mux.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/sound/soc/codecs/simple-mux.c b/sound/soc/codecs/simple-mux.c new file mode 100644 index 000000000000..390696440155 --- /dev/null +++ b/sound/soc/codecs/simple-mux.c @@ -0,0 +1,191 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2020 Bootlin SA + * Author: Alexandre Belloni <alexandre.belloni@bootlin.com> + */ + +#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_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_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 && 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, + 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, // see simple_mux_probe() + 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" }, // see simple_mux_probe() + { "MUX", "Input 2", "IN2" }, // see simple_mux_probe() +}; + +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"); + + /* Copy default settings */ + 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; + + /* 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; + priv->mux_widgets[2].kcontrol_news = &priv->mux_mux; + priv->mux_routes[1].control = priv->mux_texts[0]; // "Input 1" + priv->mux_routes[2].control = priv->mux_texts[1]; // "Input 2" + + 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"); |