Add a driver for simple mux driven by gpios. It currently only supports one gpio, muxing one of two inputs to a single output.

Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com --- sound/soc/codecs/Kconfig | 5 ++ sound/soc/codecs/Makefile | 4 ++ sound/soc/codecs/simple-mux.c | 124 ++++++++++++++++++++++++++++++++++ 3 files changed, 133 insertions(+) create mode 100644 sound/soc/codecs/simple-mux.c

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig index 34c6dd04b85a..3847e490f795 100644 --- a/sound/soc/codecs/Kconfig +++ b/sound/soc/codecs/Kconfig @@ -181,6 +181,7 @@ config SND_SOC_ALL_CODECS imply SND_SOC_SGTL5000 imply SND_SOC_SI476X imply SND_SOC_SIMPLE_AMPLIFIER + imply SND_SOC_SIMPLE_MUX imply SND_SOC_SIRF_AUDIO_CODEC imply SND_SOC_SPDIF imply SND_SOC_SSM2305 @@ -1240,6 +1241,10 @@ config SND_SOC_SIMPLE_AMPLIFIER tristate "Simple Audio Amplifier" select GPIOLIB

+config SND_SOC_SIMPLE_MUX + tristate "Simple Audio Mux" + select GPIOLIB + config SND_SOC_SIRF_AUDIO_CODEC tristate "SiRF SoC internal audio codec" select REGMAP_MMIO diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile index 11ce98c25d6c..90f1a2b7ade0 100644 --- a/sound/soc/codecs/Makefile +++ b/sound/soc/codecs/Makefile @@ -305,6 +305,8 @@ snd-soc-tpa6130a2-objs := tpa6130a2.o snd-soc-tas2552-objs := tas2552.o snd-soc-tas2562-objs := tas2562.o snd-soc-tas2764-objs := tas2764.o +# Mux +snd-soc-simple-mux-objs := simple-mux.o

obj-$(CONFIG_SND_SOC_88PM860X) += snd-soc-88pm860x.o obj-$(CONFIG_SND_SOC_AB8500_CODEC) += snd-soc-ab8500-codec.o @@ -613,3 +615,5 @@ obj-$(CONFIG_SND_SOC_MAX9877) += snd-soc-max9877.o obj-$(CONFIG_SND_SOC_MAX98504) += snd-soc-max98504.o obj-$(CONFIG_SND_SOC_SIMPLE_AMPLIFIER) += snd-soc-simple-amplifier.o obj-$(CONFIG_SND_SOC_TPA6130A2) += snd-soc-tpa6130a2.o +# Mux +obj-$(CONFIG_SND_SOC_SIMPLE_MUX) += snd-soc-simple-mux.o diff --git a/sound/soc/codecs/simple-mux.c b/sound/soc/codecs/simple-mux.c new file mode 100644 index 000000000000..e0a09dadfa7c --- /dev/null +++ b/sound/soc/codecs/simple-mux.c @@ -0,0 +1,124 @@ +// 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/regulator/consumer.h> +#include <sound/soc.h> + +struct simple_mux { + struct gpio_desc *gpiod_mux; + unsigned int mux; +}; + +static const char * const simple_mux_texts[] = { + "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]; + + 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 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 const struct snd_soc_dapm_widget simple_mux_dapm_widgets[] = { + SND_SOC_DAPM_INPUT("IN1"), + SND_SOC_DAPM_INPUT("IN2"), + SND_SOC_DAPM_MUX("MUX", SND_SOC_NOPM, 0, 0, &simple_mux_mux), + SND_SOC_DAPM_OUTPUT("OUT"), +}; + +static const struct snd_soc_dapm_route simple_mux_dapm_routes[] = { + { "OUT", NULL, "MUX" }, + { "MUX", "Input 1", "IN1" }, + { "MUX", "Input 2", "IN2" }, +}; + +static const struct snd_soc_component_driver simple_mux_component_driver = { + .dapm_widgets = simple_mux_dapm_widgets, + .num_dapm_widgets = ARRAY_SIZE(simple_mux_dapm_widgets), + .dapm_routes = simple_mux_dapm_routes, + .num_dapm_routes = ARRAY_SIZE(simple_mux_dapm_routes), +}; + +static int simple_mux_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct simple_mux *priv; + int err; + + 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)) { + err = PTR_ERR(priv->gpiod_mux); + if (err != -EPROBE_DEFER) + dev_err(dev, "Failed to get 'mux' gpio: %d", err); + return err; + } + + return devm_snd_soc_register_component(dev, &simple_mux_component_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");

On Sat, Dec 05, 2020 at 01:15:07AM +0100, Alexandre Belloni wrote:

Add devicetree documentation for simple audio multiplexers

Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com

Cc: Rob Herring robh+dt@kernel.org

.../bindings/sound/simple-audio-mux.yaml | 41 +++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/simple-audio-mux.yaml

diff --git a/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml b/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml new file mode 100644 index 000000000000..5986d1fcbb54 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml @@ -0,0 +1,41 @@ +# SPDX-License-Identifier: (GPL-2.0+ OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/sound/simple-audio-mux.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml#

+title: Simple Audio Multiplexer

+maintainers:

• • Alexandre Belloni aleandre.belloni@bootlin.com

typo

+description: |

• Simple audio multiplexers are driven using gpios, allowing to select which of
• their input line is connected to the output line.

What's wrong with the generic mux binding and driver(s)?

+properties:

• compatible:
• const: simple-audio-mux
• mux-gpios:
• description: |

•  GPIOs used to select the input line.
  

• sound-name-prefix:
• $ref: /schemas/types.yaml#/definitions/string
• description:

•  Used as prefix for sink/source names of the component. Must be a
  

•  unique string among multiple instances of the same component.
  

+required:

• • compatible
• • mux-gpios

+additionalProperties: false

+examples:

• • |
• mux {

•    compatible = "simple-audio-mux";
  

•    mux-gpios = <&gpio 3 0>;
  

• };

-- 2.28.0