[alsa-devel] [PATCH 2/2] ASoC: codecs: adau1701: add DT bindings

[Daniel Mack]

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

Signed-off-by: Daniel Mack <zonque at gmail.com>
---
 .../devicetree/bindings/sound/adi,adau1701.txt     | 23 ++++++++++++++++
 sound/soc/codecs/adau1701.c                        | 31 ++++++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/adi,adau1701.txt

diff --git a/Documentation/devicetree/bindings/sound/adi,adau1701.txt b/Documentation/devicetree/bindings/sound/adi,adau1701.txt
new file mode 100644
index 0000000..3afeda7
--- /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 at 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 95e1677..6515ba7 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>
@@ -452,13 +455,40 @@ 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;
+	struct device *dev = codec->dev;
 	struct i2c_client *client = to_i2c_client(codec->dev);
+	int gpio_nreset = -EINVAL;
 
 	codec->control_data = client;
 
+	if (of_match_device(of_match_ptr(adau1701_dt_ids), dev))
+		gpio_nreset = of_get_named_gpio(dev->of_node,
+						"reset-gpio", 0);
+
+	if (gpio_is_valid(gpio_nreset)) {
+		if (devm_gpio_request_one(codec->dev, gpio_nreset,
+					  GPIOF_OUT_INIT_LOW,
+					  "ADAU1701 Reset") < 0)
+			return -EINVAL;
+
+		/* minimum reset time is 20ns */
+		udelay(1);
+		gpio_set_value(gpio_nreset, 1);
+		/* power-up time may be as long as 85ms */
+		mdelay(85);
+	}
+
 	ret = adau1701_load_firmware(client);
 	if (ret)
 		dev_warn(codec->dev, "Failed to load firmware\n");
@@ -522,6 +552,7 @@ 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,
-- 
1.8.1.4