2 files changed, 22 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sound/cs4270.txt b/Documentation/devicetree/bindings/sound/cs4270.txt
index 7f0bfd84d3fc..6b222f9b8ef5 100644
--- a/Documentation/devicetree/bindings/sound/cs4270.txt
+++ b/Documentation/devicetree/bindings/sound/cs4270.txt
@@ -8,6 +8,11 @@ Required properties:
 
   - reg : the I2C address of the device for I2C
 
+Optional properties:
+
+  - reset-gpio : a GPIO spec for the reset pin. If specified, it will be
+                 deasserted before communication to the codec starts.
+
 Example:
 
 codec: cs4270@48 {
diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
index 4b71b01ecbcd..fd11bb646d40 100644
--- a/sound/soc/codecs/cs4270.c
+++ b/sound/soc/codecs/cs4270.c
@@ -30,6 +30,7 @@
 #include <linux/delay.h>
 #include <linux/regulator/consumer.h>
 #include <linux/of_device.h>
+#include <linux/of_gpio.h>
 
 /*
  * The codec isn't really big-endian or little-endian, since the I2S
@@ -660,9 +661,25 @@ MODULE_DEVICE_TABLE(of, cs4270_of_match);
 static int cs4270_i2c_probe(struct i2c_client *i2c_client,
         const struct i2c_device_id *id)
 {
+        struct device_node *np = i2c_client->dev.of_node;
         struct cs4270_private *cs4270;
         int ret;
 
+        /* See if we have a way to bring the codec out of reset */
+        if (np) {
+                enum of_gpio_flags flags;
+                int gpio = of_get_named_gpio_flags(np, "reset-gpio", 0, &flags);
+
+                if (gpio_is_valid(gpio)) {
+                        ret = devm_gpio_request_one(&i2c_client->dev, gpio,
+                                     flags & OF_GPIO_ACTIVE_LOW ?
+                                        GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH,
+                                     "cs4270 reset");
+                        if (ret < 0)
+                                return ret;
+                }
+        }
+
         /* Verify that we have a CS4270 */
 
         ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID);