[PATCH v16 01/10] video: backlight: Add helpers to enable and disable backlight

[Meghana Madhyastha]

Add helper functions backlight_enable and backlight_disable to
enable/disable a backlight device. These helper functions can
then be used by different drm and tinydrm drivers to avoid
repetition of code and also to enforce a uniform and consistent
way to enable/disable a backlight device.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha at gmail.com>
---
 include/linux/backlight.h | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index af7003548..7b6a9a2a3 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -130,6 +130,36 @@ static inline int backlight_update_status(struct backlight_device *bd)
 	return ret;
 }
 
+/**
+  * backlight_enable - Enable backlight
+  * @bd: the backlight device to enable
+  */
+static inline int backlight_enable(struct backlight_device *bd)
+{
+	if (!bd)
+		return 0;
+
+	bd->props.power = FB_BLANK_UNBLANK;
+	bd->props.state &= ~BL_CORE_FBBLANK;
+
+	return backlight_update_status(bd);
+}
+
+/**
+  * backlight_disable - Disable backlight
+  * @bd: the backlight device to disable
+  */
+static inline int backlight_disable(struct backlight_device *bd)
+{
+	if (!bd)
+		return 0;
+		
+	bd->props.power = FB_BLANK_POWERDOWN;
+	bd->props.state |= BL_CORE_FBBLANK;
+
+	return backlight_update_status(bd);
+}
+
 extern struct backlight_device *backlight_device_register(const char *name,
 	struct device *dev, void *devdata, const struct backlight_ops *ops,
 	const struct backlight_properties *props);
-- 
2.11.0