ASoC: wm8962: Add device tree binding

Document the device tree binding for the WM8962 codec, and modify the
driver to extract platform data from the device tree, if present.

Based on work of WM8903 by Stephen Warren <swarren@nvidia.com>

Signed-off-by: Nicolin Chen <b42378@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/codecs/wm8962.c b/sound/soc/codecs/wm8962.c
index d56dd86..26219ea 100644
--- a/sound/soc/codecs/wm8962.c
+++ b/sound/soc/codecs/wm8962.c
@@ -3584,6 +3584,34 @@
 	.cache_type = REGCACHE_RBTREE,
 };
 
+static int wm8962_set_pdata_from_of(struct i2c_client *i2c,
+				    struct wm8962_pdata *pdata)
+{
+	const struct device_node *np = i2c->dev.of_node;
+	u32 val32;
+	int i;
+
+	if (of_property_read_bool(np, "spk-mono"))
+		pdata->spk_mono = true;
+
+	if (of_property_read_u32(np, "mic-cfg", &val32) >= 0)
+		pdata->mic_cfg = val32;
+
+	if (of_property_read_u32_array(np, "gpio-cfg", pdata->gpio_init,
+				       ARRAY_SIZE(pdata->gpio_init)) >= 0)
+		for (i = 0; i < ARRAY_SIZE(pdata->gpio_init); i++) {
+			/*
+			 * The range of GPIO register value is [0x0, 0xffff]
+			 * While the default value of each register is 0x0
+			 * Any other value will be regarded as default value
+			 */
+			if (pdata->gpio_init[i] > 0xffff)
+				pdata->gpio_init[i] = 0x0;
+		}
+
+	return 0;
+}
+
 static int wm8962_i2c_probe(struct i2c_client *i2c,
 			    const struct i2c_device_id *id)
 {
@@ -3604,8 +3632,13 @@
 	wm8962->irq = i2c->irq;
 
 	/* If platform data was supplied, update the default data in priv */
-	if (pdata)
+	if (pdata) {
 		memcpy(&wm8962->pdata, pdata, sizeof(struct wm8962_pdata));
+	} else if (i2c->dev.of_node) {
+		ret = wm8962_set_pdata_from_of(i2c, &wm8962->pdata);
+		if (ret != 0)
+			return ret;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(wm8962->supplies); i++)
 		wm8962->supplies[i].supply = wm8962_supply_names[i];