ASoC: WM8903: Add device tree binding

Document the device tree binding for the WM8903 codec, and modify the
driver to extract platform data from the device tree, if present.

Based on work by John Bonesio, but significantly reworked since then.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/sound/soc/codecs/wm8903.c b/sound/soc/codecs/wm8903.c
index b4f2c906b2f3..adfbefaaab21 100644
--- a/sound/soc/codecs/wm8903.c
+++ b/sound/soc/codecs/wm8903.c
@@ -2070,6 +2070,49 @@ static int wm8903_set_pdata_irq_trigger(struct i2c_client *i2c,
         return 0;
 }
 
+static int wm8903_set_pdata_from_of(struct i2c_client *i2c,
+                                    struct wm8903_platform_data *pdata)
+{
+        const struct device_node *np = i2c->dev.of_node;
+        u32 val32;
+        int i;
+
+        if (of_property_read_u32(np, "micdet-cfg", &val32) >= 0)
+                pdata->micdet_cfg = val32;
+
+        if (of_property_read_u32(np, "micdet-delay", &val32) >= 0)
+                pdata->micdet_delay = val32;
+
+        if (of_property_read_u32_array(np, "gpio-cfg", pdata->gpio_cfg,
+                                       ARRAY_SIZE(pdata->gpio_cfg)) >= 0) {
+                /*
+                 * In device tree: 0 means "write 0",
+                 * 0xffffffff means "don't touch".
+                 *
+                 * In platform data: 0 means "don't touch",
+                 * 0x8000 means "write 0".
+                 *
+                 * Note: WM8903_GPIO_CONFIG_ZERO == 0x8000.
+                 *
+                 *  Convert from DT to pdata representation here,
+                 * so no other code needs to change.
+                 */
+                for (i = 0; i < ARRAY_SIZE(pdata->gpio_cfg); i++) {
+                        if (pdata->gpio_cfg[i] == 0) {
+                                pdata->gpio_cfg[i] = WM8903_GPIO_CONFIG_ZERO;
+                        } else if (pdata->gpio_cfg[i] == 0xffffffff) {
+                                pdata->gpio_cfg[i] = 0;
+                        } else if (pdata->gpio_cfg[i] > 0x7fff) {
+                                dev_err(&i2c->dev, "Invalid gpio-cfg[%d] %x\n",
+                                        i, pdata->gpio_cfg[i]);
+                                return -EINVAL;
+                        }
+                }
+        }
+
+        return 0;
+}
+
 static __devinit int wm8903_i2c_probe(struct i2c_client *i2c,
                                       const struct i2c_device_id *id)
 {
@@ -2111,6 +2154,12 @@ static __devinit int wm8903_i2c_probe(struct i2c_client *i2c,
                         if (ret != 0)
                                 return ret;
                 }
+
+                if (i2c->dev.of_node) {
+                        ret = wm8903_set_pdata_from_of(i2c, wm8903->pdata);
+                        if (ret != 0)
+                                return ret;
+                }
         }
 
         ret = regmap_read(wm8903->regmap, WM8903_SW_RESET_AND_ID, &val);