ASoC: ssm2602: add device tree bindings

Allow the ssm2602/ssm2603/ssm2604 codec driver to be
instantiated from the device tree.

Also, add Kconfig prompts to allow manual selection of both the
I2C and SPI configuration versions of the driver.
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>

Documentation/devicetree/bindings/sound/adi,ssm2602.txt

+Analog Devices SSM2602, SSM2603 and SSM2604 I2S audio CODEC devices
+
+SSM2602 support both I2C and SPI as the configuration interface,
+the selection is made by the MODE strap-in pin.
+SSM2603 and SSM2604 only support I2C as the configuration interface.
+
+Required properties:
+
+  - compatible : One of "adi,ssm2602", "adi,ssm2603" or "adi,ssm2604"
+
+  - reg : the I2C address of the device for I2C, the chip select
+          number for SPI.
+
+ Example:
+
+	ssm2602: ssm2602@1a {
+		compatible = "adi,ssm2602";
+		reg = <0x1a>;
+	};

sound/soc/codecs/Kconfig

@@ -520,12 +520,16 @@ config SND_SOC_SSM2602
 	tristate
 
 config SND_SOC_SSM2602_SPI
+	tristate "Analog Devices SSM2602 CODEC - SPI"
+	depends on SPI_MASTER
 	select SND_SOC_SSM2602
-	tristate
+	select REGMAP_SPI
 
 config SND_SOC_SSM2602_I2C
+	tristate "Analog Devices SSM2602 CODEC - I2C"
+	depends on I2C
 	select SND_SOC_SSM2602
-	tristate
+	select REGMAP_I2C
 
 config SND_SOC_STA32X
 	tristate

sound/soc/codecs/ssm2602-i2c.c

@@ -41,10 +41,19 @@ static const struct i2c_device_id ssm2602_i2c_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, ssm2602_i2c_id);
 
+static const struct of_device_id ssm2602_of_match[] = {
+	{ .compatible = "adi,ssm2602", },
+	{ .compatible = "adi,ssm2603", },
+	{ .compatible = "adi,ssm2604", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ssm2602_of_match);
+
 static struct i2c_driver ssm2602_i2c_driver = {
 	.driver = {
 		.name = "ssm2602",
 		.owner = THIS_MODULE,
+		.of_match_table = ssm2602_of_match,
 	},
 	.probe = ssm2602_i2c_probe,
 	.remove = ssm2602_i2c_remove,

sound/soc/codecs/ssm2602-spi.c

@@ -26,10 +26,17 @@ static int ssm2602_spi_remove(struct spi_device *spi)
 	return 0;
 }
 
+static const struct of_device_id ssm2602_of_match[] = {
+	{ .compatible = "adi,ssm2602", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ssm2602_of_match);
+
 static struct spi_driver ssm2602_spi_driver = {
 	.driver = {
 		.name	= "ssm2602",
 		.owner	= THIS_MODULE,
+		.of_match_table = ssm2602_of_match,
 	},
 	.probe		= ssm2602_spi_probe,
 	.remove		= ssm2602_spi_remove,