Merge tag 'backlight-for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel...

Pull backlight updates from Lee Jones:
 "Add support for an enable regulator to lp855x_bl"

* tag 'backlight-for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: lp855x: Add enable regulator

diff --git a/Documentation/devicetree/bindings/leds/backlight/lp855x.txt b/Documentation/devicetree/bindings/leds/backlight/lp855x.txt
index 0a3ecbc..88f5664 100644 (file)
--- a/Documentation/devicetree/bindings/leds/backlight/lp855x.txt
+++ b/Documentation/devicetree/bindings/leds/backlight/lp855x.txt
@@ -13,6 +13,7 @@ Optional properties:
   - rom-addr: Register address of ROM area to be updated (u8)
   - rom-val: Register value to be updated (u8)
   - power-supply: Regulator which controls the 3V rail
+  - enable-supply: Regulator which controls the EN/VDDIO input
 
 Example:
 
@@ -57,6 +58,7 @@ Example:
        backlight@2c {
                compatible = "ti,lp8557";
                reg = <0x2c>;
+               enable-supply = <&backlight_vddio>;
                power-supply = <&backlight_vdd>;
 
                dev-ctrl = /bits/ 8 <0x41>;

diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c
index e5b14f5..939f057 100644 (file)
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -13,6 +13,7 @@
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/backlight.h>
+#include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/of.h>
 #include <linux/platform_data/lp855x.h>
@@ -74,6 +75,7 @@ struct lp855x {
        struct lp855x_platform_data *pdata;
        struct pwm_device *pwm;
        struct regulator *supply;       /* regulator for VDD input */
+       struct regulator *enable;       /* regulator for EN/VDDIO input */
 };
 
 static int lp855x_write_byte(struct lp855x *lp, u8 reg, u8 data)
@@ -433,6 +435,19 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
                lp->supply = NULL;
        }
 
+       lp->enable = devm_regulator_get_optional(lp->dev, "enable");
+       if (IS_ERR(lp->enable)) {
+               ret = PTR_ERR(lp->enable);
+               if (ret == -ENODEV) {
+                       lp->enable = NULL;
+               } else {
+                       if (ret != -EPROBE_DEFER)
+                               dev_err(lp->dev, "error getting enable regulator: %d\n",
+                                       ret);
+                       return ret;
+               }
+       }
+
        if (lp->supply) {
                ret = regulator_enable(lp->supply);
                if (ret < 0) {
@@ -441,6 +456,20 @@ static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
                }
        }
 
+       if (lp->enable) {
+               ret = regulator_enable(lp->enable);
+               if (ret < 0) {
+                       dev_err(lp->dev, "failed to enable vddio: %d\n", ret);
+                       return ret;
+               }
+
+               /*
+                * LP8555 datasheet says t_RESPONSE (time between VDDIO and
+                * I2C) is 1ms.
+                */
+               usleep_range(1000, 2000);
+       }
+
        i2c_set_clientdata(cl, lp);
 
        ret = lp855x_configure(lp);