ASoC: ssm2305: Add amplifier driver

The ssm2305 is a simple Class-D audio amplifier. A application can
turn on/off the device by a gpio. It's also possible to hardwire the
shutdown pin.

Tested on a i.MX6 based custom board.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/sound/adi,ssm2305.txt b/Documentation/devicetree/bindings/sound/adi,ssm2305.txt
new file mode 100644 (file)
index 0000000..a9c9d83
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/adi,ssm2305.txt
@@ -0,0 +1,14 @@
+Analog Devices SSM2305 Speaker Amplifier
+========================================
+
+Required properties:
+  - compatible : "adi,ssm2305"
+  - shutdown-gpios : The gpio connected to the shutdown pin.
+                     The gpio signal is ACTIVE_LOW.
+
+Example:
+
+ssm2305: analog-amplifier {
+       compatible = "adi,ssm2305";
+       shutdown-gpios = <&gpio3 20 GPIO_ACTIVE_LOW>;
+};

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 83c51c5..a3e7c44 100644 (file)
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -145,6 +145,7 @@ config SND_SOC_ALL_CODECS
        select SND_SOC_SI476X if MFD_SI476X_CORE
        select SND_SOC_SIRF_AUDIO_CODEC
        select SND_SOC_SPDIF
+       select SND_SOC_SSM2305
        select SND_SOC_SSM2518 if I2C
        select SND_SOC_SSM2602_SPI if SPI_MASTER
        select SND_SOC_SSM2602_I2C if I2C
@@ -896,6 +897,12 @@ config SND_SOC_SIRF_AUDIO_CODEC
 config SND_SOC_SPDIF
        tristate "S/PDIF CODEC"
 
+config SND_SOC_SSM2305
+       tristate "Analog Devices SSM2305 Class-D Amplifier"
+       help
+         Enable support for Analog Devices SSM2305 filterless
+         high-efficiency mono Class-D audio power amplifiers.
+
 config SND_SOC_SSM2518
        tristate
 

diff --git a/sound/soc/codecs/Makefile b/sound/soc/codecs/Makefile
index 1ac49b9..4c85f33 100644 (file)
--- a/sound/soc/codecs/Makefile
+++ b/sound/soc/codecs/Makefile
@@ -156,6 +156,7 @@ snd-soc-si476x-objs := si476x.o
 snd-soc-sirf-audio-codec-objs := sirf-audio-codec.o
 snd-soc-spdif-tx-objs := spdif_transmitter.o
 snd-soc-spdif-rx-objs := spdif_receiver.o
+snd-soc-ssm2305-objs := ssm2305.o
 snd-soc-ssm2518-objs := ssm2518.o
 snd-soc-ssm2602-objs := ssm2602.o
 snd-soc-ssm2602-spi-objs := ssm2602-spi.o
@@ -410,6 +411,7 @@ obj-$(CONFIG_SND_SOC_SIGMADSP_REGMAP)       += snd-soc-sigmadsp-regmap.o
 obj-$(CONFIG_SND_SOC_SI476X)   += snd-soc-si476x.o
 obj-$(CONFIG_SND_SOC_SPDIF)    += snd-soc-spdif-rx.o snd-soc-spdif-tx.o
 obj-$(CONFIG_SND_SOC_SIRF_AUDIO_CODEC) += sirf-audio-codec.o
+obj-$(CONFIG_SND_SOC_SSM2305)  += snd-soc-ssm2305.o
 obj-$(CONFIG_SND_SOC_SSM2518)  += snd-soc-ssm2518.o
 obj-$(CONFIG_SND_SOC_SSM2602)  += snd-soc-ssm2602.o
 obj-$(CONFIG_SND_SOC_SSM2602_SPI)      += snd-soc-ssm2602-spi.o

diff --git a/sound/soc/codecs/ssm2305.c b/sound/soc/codecs/ssm2305.c
new file mode 100644 (file)
index 0000000..39d8b01
--- /dev/null
+++ b/sound/soc/codecs/ssm2305.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices SSM2305 Amplifier Driver
+ *
+ * Copyright (C) 2018 Pengutronix, Marco Felsch <kernel@pengutronix.de>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <sound/soc.h>
+
+#define DRV_NAME "ssm2305"
+
+struct ssm2305 {
+       /* shutdown gpio  */
+       struct gpio_desc *gpiod_shutdown;
+};
+
+static int ssm2305_power_event(struct snd_soc_dapm_widget *w,
+                              struct snd_kcontrol *kctrl, int event)
+{
+       struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
+       struct ssm2305 *data = snd_soc_component_get_drvdata(c);
+
+       gpiod_set_value_cansleep(data->gpiod_shutdown,
+                                SND_SOC_DAPM_EVENT_ON(event));
+
+       return 0;
+}
+
+static const struct snd_soc_dapm_widget ssm2305_dapm_widgets[] = {
+       /* Stereo input/output */
+       SND_SOC_DAPM_INPUT("L_IN"),
+       SND_SOC_DAPM_INPUT("R_IN"),
+       SND_SOC_DAPM_OUTPUT("L_OUT"),
+       SND_SOC_DAPM_OUTPUT("R_OUT"),
+
+       SND_SOC_DAPM_SUPPLY("Power", SND_SOC_NOPM, 0, 0, ssm2305_power_event,
+                           SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
+};
+
+static const struct snd_soc_dapm_route ssm2305_dapm_routes[] = {
+       { "L_OUT", NULL, "L_IN" },
+       { "R_OUT", NULL, "R_IN" },
+       { "L_IN", NULL, "Power" },
+       { "R_IN", NULL, "Power" },
+};
+
+static const struct snd_soc_component_driver ssm2305_component_driver = {
+       .dapm_widgets           = ssm2305_dapm_widgets,
+       .num_dapm_widgets       = ARRAY_SIZE(ssm2305_dapm_widgets),
+       .dapm_routes            = ssm2305_dapm_routes,
+       .num_dapm_routes        = ARRAY_SIZE(ssm2305_dapm_routes),
+};
+
+static int ssm2305_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct ssm2305 *priv;
+       int err;
+
+       /* Allocate the private data */
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       platform_set_drvdata(pdev, priv);
+
+       /* Get shutdown gpio */
+       priv->gpiod_shutdown = devm_gpiod_get(dev, "shutdown",
+                                             GPIOD_OUT_LOW);
+       if (IS_ERR(priv->gpiod_shutdown)) {
+               err = PTR_ERR(priv->gpiod_shutdown);
+               if (err != -EPROBE_DEFER)
+                       dev_err(dev, "Failed to get 'shutdown' gpio: %d\n",
+                               err);
+               return err;
+       }
+
+       return devm_snd_soc_register_component(dev, &ssm2305_component_driver,
+                                              NULL, 0);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id ssm2305_of_match[] = {
+       { .compatible = "adi,ssm2305", },
+       { }
+};
+MODULE_DEVICE_TABLE(of, ssm2305_of_match);
+#endif
+
+static struct platform_driver ssm2305_driver = {
+       .driver = {
+               .name = DRV_NAME,
+               .of_match_table = of_match_ptr(ssm2305_of_match),
+       },
+       .probe = ssm2305_probe,
+};
+
+module_platform_driver(ssm2305_driver);
+
+MODULE_DESCRIPTION("ASoC SSM2305 amplifier driver");
+MODULE_AUTHOR("Marco Felsch <m.felsch@pengutronix.de>");
+MODULE_LICENSE("GPL v2");