ASoC: codecs: adau1701: add DT bindings

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

Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 57 insertions, 1 deletions

diff --git a/Documentation/devicetree/bindings/sound/adi,adau1701.txt b/Documentation/devicetree/bindings/sound/adi,adau1701.txt
new file mode 100644
index 000000000000..3afeda77b5b9
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/adi,adau1701.txt
@@ -0,0 +1,23 @@
+Analog Devices ADAU1701
+
+Required properties:
+
+ - compatible:          Should contain "adi,adau1701"
+ - reg:                 The i2c address. Value depends on the state of ADDR0
+                        and ADDR1, as wired in hardware.
+
+Optional properties:
+
+ - reset-gpio:          A GPIO spec to define which pin is connected to the
+                        chip's !RESET pin. If specified, the driver will
+                        assert a hardware reset at probe time.
+
+Examples:
+
+        i2c_bus {
+                adau1701@34 {
+                        compatible = "adi,adau1701";
+                        reg = <0x34>;
+                        reset-gpio = <&gpio 23 0>;
+                };
+        };
diff --git a/sound/soc/codecs/adau1701.c b/sound/soc/codecs/adau1701.c
index 95e1677665e9..3fc176387351 100644
--- a/sound/soc/codecs/adau1701.c
+++ b/sound/soc/codecs/adau1701.c
@@ -13,6 +13,9 @@
 #include <linux/i2c.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_device.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
@@ -452,6 +455,14 @@ static struct snd_soc_dai_driver adau1701_dai = {
         .symmetric_rates = 1,
 };
 
+#ifdef CONFIG_OF
+static const struct of_device_id adau1701_dt_ids[] = {
+        { .compatible = "adi,adau1701", },
+        { }
+};
+MODULE_DEVICE_TABLE(of, adau1701_dt_ids);
+#endif
+
 static int adau1701_probe(struct snd_soc_codec *codec)
 {
         int ret;
@@ -494,12 +505,33 @@ static int adau1701_i2c_probe(struct i2c_client *client,
                               const struct i2c_device_id *id)
 {
         struct adau1701 *adau1701;
+        struct device *dev = &client->dev;
+        int gpio_nreset = -EINVAL;
         int ret;
 
-        adau1701 = devm_kzalloc(&client->dev, sizeof(*adau1701), GFP_KERNEL);
+        adau1701 = devm_kzalloc(dev, sizeof(*adau1701), GFP_KERNEL);
         if (!adau1701)
                 return -ENOMEM;
 
+        if (dev->of_node) {
+                gpio_nreset = of_get_named_gpio(dev->of_node, "reset-gpio", 0);
+                if (gpio_nreset < 0 && gpio_nreset != -ENOENT)
+                        return gpio_nreset;
+        }
+
+        if (gpio_is_valid(gpio_nreset)) {
+                ret = devm_gpio_request_one(dev, gpio_nreset, GPIOF_OUT_INIT_LOW,
+                                            "ADAU1701 Reset");
+                if (ret < 0)
+                        return ret;
+
+                /* minimum reset time is 20ns */
+                udelay(1);
+                gpio_set_value(gpio_nreset, 1);
+                /* power-up time may be as long as 85ms */
+                mdelay(85);
+        }
+
         i2c_set_clientdata(client, adau1701);
         ret = snd_soc_register_codec(&client->dev, &adau1701_codec_drv,
                         &adau1701_dai, 1);
@@ -522,6 +554,7 @@ static struct i2c_driver adau1701_i2c_driver = {
         .driver = {
                 .name   = "adau1701",
                 .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(adau1701_dt_ids),
         },
         .probe          = adau1701_i2c_probe,
         .remove         = adau1701_i2c_remove,