ALSA: ASoC: add DT bindings for CS4271

Apart from pure matching, the bindings also support setting the the
reset gpio line.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Cc: Alexander Sverdlin <subaparts@yandex.ru>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 57 insertions, 3 deletions

diff --git a/Documentation/devicetree/bindings/sound/cs4271.txt b/Documentation/devicetree/bindings/sound/cs4271.txt
new file mode 100644
index 000000000000..c81b5fd5a5bc
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/cs4271.txt
@@ -0,0 +1,36 @@
+Cirrus Logic CS4271 DT bindings
+
+This driver supports both the I2C and the SPI bus.
+
+Required properties:
+
+ - compatible: "cirrus,cs4271"
+
+For required properties on SPI, please consult
+Documentation/devicetree/bindings/spi/spi-bus.txt
+
+Required properties on I2C:
+
+ - reg: the i2c address
+
+
+Optional properties:
+
+ - reset-gpio:  a GPIO spec to define which pin is connected to the chip's
+                !RESET pin
+
+Examples:
+
+        codec_i2c: cs4271@10 {
+                compatible = "cirrus,cs4271";
+                reg = <0x10>;
+                reset-gpio = <&gpio 23 0>;
+        };
+
+        codec_spi: cs4271@0 {
+                compatible = "cirrus,cs4271";
+                reg = <0x0>;
+                reset-gpio = <&gpio 23 0>;
+                spi-max-frequency = <6000000>;
+        };
+
diff --git a/sound/soc/codecs/cs4271.c b/sound/soc/codecs/cs4271.c
index 9eb01d7d58a3..f994af34f552 100644
--- a/sound/soc/codecs/cs4271.c
+++ b/sound/soc/codecs/cs4271.c
@@ -22,12 +22,14 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
-#include <sound/pcm.h>
-#include <sound/soc.h>
-#include <sound/tlv.h>
 #include <linux/gpio.h>
 #include <linux/i2c.h>
 #include <linux/spi/spi.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include <sound/tlv.h>
 #include <sound/cs4271.h>
 
 #define CS4271_PCM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
@@ -458,6 +460,14 @@ static int cs4271_soc_resume(struct snd_soc_codec *codec)
 #define cs4271_soc_resume       NULL
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_OF
+static const struct of_device_id cs4271_dt_ids[] = {
+        { .compatible = "cirrus,cs4271", },
+        { }
+};
+MODULE_DEVICE_TABLE(of, cs4271_dt_ids);
+#endif
+
 static int cs4271_probe(struct snd_soc_codec *codec)
 {
         struct cs4271_private *cs4271 = snd_soc_codec_get_drvdata(codec);
@@ -465,6 +475,12 @@ static int cs4271_probe(struct snd_soc_codec *codec)
         int ret;
         int gpio_nreset = -EINVAL;
 
+#ifdef CONFIG_OF
+        if (of_match_device(cs4271_dt_ids, codec->dev))
+                gpio_nreset = of_get_named_gpio(codec->dev->of_node,
+                                                "reset-gpio", 0);
+#endif
+
         if (cs4271plat && gpio_is_valid(cs4271plat->gpio_nreset))
                 gpio_nreset = cs4271plat->gpio_nreset;
 
@@ -569,6 +585,7 @@ static struct spi_driver cs4271_spi_driver = {
         .driver = {
                 .name   = "cs4271",
                 .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(cs4271_dt_ids),
         },
         .probe          = cs4271_spi_probe,
         .remove         = __devexit_p(cs4271_spi_remove),
@@ -608,6 +625,7 @@ static struct i2c_driver cs4271_i2c_driver = {
         .driver = {
                 .name   = "cs4271",
                 .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(cs4271_dt_ids),
         },
         .id_table       = cs4271_i2c_id,
         .probe          = cs4271_i2c_probe,