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authorNoralf Trønnes <noralf@tronnes.org>2020-05-09 16:16:10 +0200
committerLee Jones <lee.jones@linaro.org>2020-05-11 07:39:16 +0100
commit479da1f538a2f3547e15f9d5922c611b69ec2fbc (patch)
tree2ebc2934ac8ba1d0129981f79cd05f257449e4dd /drivers/video/backlight
parent62a1d3f623ac0338912fdfbdda9bdac4cadcbc75 (diff)
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backlight: Add backlight_device_get_by_name()
Add a way to lookup a backlight device based on its name. Will be used by a USB display gadget getting the name from configfs. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Acked-by: Jingoo Han <jingoohan1@gmail.com> Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers/video/backlight')
-rw-r--r--drivers/video/backlight/backlight.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index cac3e35d7630..92d80aa0c0ef 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -433,6 +433,27 @@ struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
EXPORT_SYMBOL(backlight_device_get_by_type);
/**
+ * backlight_device_get_by_name - Get backlight device by name
+ * @name: Device name
+ *
+ * This function looks up a backlight device by its name. It obtains a reference
+ * on the backlight device and it is the caller's responsibility to drop the
+ * reference by calling backlight_put().
+ *
+ * Returns:
+ * A pointer to the backlight device if found, otherwise NULL.
+ */
+struct backlight_device *backlight_device_get_by_name(const char *name)
+{
+ struct device *dev;
+
+ dev = class_find_device_by_name(backlight_class, name);
+
+ return dev ? to_backlight_device(dev) : NULL;
+}
+EXPORT_SYMBOL(backlight_device_get_by_name);
+
+/**
* backlight_device_unregister - unregisters a backlight device object.
* @bd: the backlight device object to be unregistered and freed.
*