From 8177bd0736cb63a4deb6e73f9fb2e4cc2aaf647c Mon Sep 17 00:00:00 2001
From: Sam Ravnborg <sam@ravnborg.org>
Date: Sun, 19 Jul 2020 10:07:36 +0200
Subject: backlight: backlight: Introduce backlight_get_brightness()
Git-commit: 2144d00ed0db28c764513080f95e4c49ea9133b0
Patch-mainline: v5.9-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
Based on an idea from Emil Velikov, add a helper that checks
backlight_is_blank() and return 0 as brightness if display is blank or
the property value if not.
This allows us to simplify the update_status() implementation
in most of the backlight drivers.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
include/linux/backlight.h | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index f770b78b2176..c0ef6a9537d4 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -194,6 +194,25 @@ static inline bool backlight_is_blank(const struct backlight_device *bd)
bd->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK);
}
+/**
+ * backlight_get_brightness - Returns the current brightness value
+ * @bd: the backlight device
+ *
+ * Returns the current brightness value, taking in consideration the current
+ * state. If backlight_is_blank() returns true then return 0 as brightness
+ * otherwise return the current brightness property value.
+ *
+ * Backlight drivers are expected to use this function in their update_status()
+ * operation to get the brightness value.
+ */
+static inline int backlight_get_brightness(const struct backlight_device *bd)
+{
+ if (backlight_is_blank(bd))
+ return 0;
+ else
+ return bd->props.brightness;
+}
+
struct backlight_device *
backlight_device_register(const char *name, struct device *dev, void *devdata,
const struct backlight_ops *ops,
--
2.29.2