new file mode 100644
@@ -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>;
+};
@@ -142,6 +142,7 @@ 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
@@ -883,6 +884,12 @@ 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
@@ -153,6 +153,7 @@ 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
@@ -404,6 +405,7 @@ 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
new file mode 100644
@@ -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");
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> --- Notes (changelog): v2: - fix copyright information - rename shutdown gpio and add some more documentation - mark shutdown gpio as required - rm registration information v3: - fix error handling .../devicetree/bindings/sound/adi,ssm2305.txt | 14 +++ sound/soc/codecs/Kconfig | 7 ++ sound/soc/codecs/Makefile | 2 + sound/soc/codecs/ssm2305.c | 104 ++++++++++++++++++ 4 files changed, 127 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/adi,ssm2305.txt create mode 100644 sound/soc/codecs/ssm2305.c