ASoC: ak4104: add reset line property to DT bindings

This device doesn't have a pdata definition for legacy boards, and
unless anyone need to control the reset GPIO, it's not worth adding one.
So this feature is only available to DT users for now.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/Documentation/devicetree/bindings/sound/ak4104.txt b/Documentation/devicetree/bindings/sound/ak4104.txt
index 1f8e5066d443163cd4504c0944c786242e33dbab..b902ee39cf8973bae24217f329c5c24ab8d012bb 100644 (file)
--- a/Documentation/devicetree/bindings/sound/ak4104.txt
+++ b/Documentation/devicetree/bindings/sound/ak4104.txt
@@ -8,6 +8,11 @@ Required properties:
 
   - reg : The chip select number on the SPI bus
 
+Optional properties:
+
+  - reset-gpio : a GPIO spec for the reset pin. If specified, it will be
+                deasserted before communication to the device starts.
+
 Example:
 
 spdif: ak4104@0 {

diff --git a/sound/soc/codecs/ak4104.c b/sound/soc/codecs/ak4104.c
index d4d4858088940526105002be6a22870b9d48c0e9..eec086b226f74f436a491c7413c5b63f48b3c4b7 100644 (file)
--- a/sound/soc/codecs/ak4104.c
+++ b/sound/soc/codecs/ak4104.c
@@ -15,6 +15,8 @@
 #include <sound/soc.h>
 #include <sound/initval.h>
 #include <linux/spi/spi.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
 #include <sound/asoundef.h>
 
 /* AK4104 registers addresses */
@@ -204,6 +206,7 @@ static const struct regmap_config ak4104_regmap = {
 
 static int ak4104_spi_probe(struct spi_device *spi)
 {
+       struct device_node *np = spi->dev.of_node;
        struct ak4104_private *ak4104;
        unsigned int val;
        int ret;
@@ -225,6 +228,20 @@ static int ak4104_spi_probe(struct spi_device *spi)
                return ret;
        }
 
+       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(&spi->dev, gpio,
+                                    flags & OF_GPIO_ACTIVE_LOW ?
+                                       GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH,
+                                    "ak4104 reset");
+                       if (ret < 0)
+                               return ret;
+               }
+       }
+
        /* read the 'reserved' register - according to the datasheet, it
         * should contain 0x5b. Not a good way to verify the presence of
         * the device, but there is no hardware ID register. */