From 1c91b46555aa1dd86331025e62d55d92459e0faf Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:26 +0200 Subject: backlight: backlight: Add backlight_is_blank() The backlight support has three properties that express the state: - power - state - fb_blank It is un-documented and easy to get wrong. Add backlight_is_blank() helper to make it simpler for drivers to get the check of the state correct. A lot of drivers also includes checks for fb_blank. This check is redundant when the state is checked and thus not needed in this helper function. But added anyway to avoid introducing subtle bugs due to the creative use of fb_blank in some drivers. Introducing this helper will for some drivers results in added support for fb_blank. This will be a change in functionality, which will improve the backlight driver. Rolling out this helper to all relevant backlight drivers will eliminate almost all accesses to fb_blank. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Peter Ujfalusi Reviewed-by: Emil Velikov Reviewed-by: Daniel Vetter Signed-off-by: Lee Jones --- include/linux/backlight.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 56e4580d4f55..56e51ebab740 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -175,6 +175,25 @@ static inline void backlight_put(struct backlight_device *bd) put_device(&bd->dev); } +/** + * backlight_is_blank - Return true if display is expected to be blank + * @bd: the backlight device + * + * Display is expected to be blank if any of these is true:: + * + * 1) if power in not UNBLANK + * 2) if fb_blank is not UNBLANK + * 3) if state indicate BLANK or SUSPENDED + * + * Returns true if display is expected to be blank, false otherwise. + */ +static inline bool backlight_is_blank(const struct backlight_device *bd) +{ + return bd->props.power != FB_BLANK_UNBLANK || + bd->props.fb_blank != FB_BLANK_UNBLANK || + bd->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK); +} + 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); -- cgit From ca7c20b2132d228ec76df3c96f5d0b5ae3d6f218 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:27 +0200 Subject: backlight: backlight: Improve backlight_ops documentation Improve the documentation for backlight_ops and adapt it to kernel-doc style. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones --- include/linux/backlight.h | 59 ++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 53 insertions(+), 6 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 56e51ebab740..4ff60774ae22 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -55,19 +55,66 @@ enum backlight_scale { struct backlight_device; struct fb_info; +/** + * struct backlight_ops - backlight operations + * + * The backlight operations are specified when the backlight device is registered. + */ struct backlight_ops { + /** + * @options: Configure how operations are called from the core. + * + * The options parameter is used to adjust the behaviour of the core. + * Set BL_CORE_SUSPENDRESUME to get the update_status() operation called + * upon suspend and resume. + */ unsigned int options; #define BL_CORE_SUSPENDRESUME (1 << 0) - /* Notify the backlight driver some property has changed */ + /** + * @update_status: Operation called when properties have changed. + * + * Notify the backlight driver some property has changed. + * The update_status operation is protected by the update_lock. + * + * The backlight driver is expected to use backlight_is_blank() + * to check if the display is blanked and set brightness accordingly. + * update_status() is called when any of the properties has changed. + * + * RETURNS: + * + * 0 on success, negative error code if any failure occurred. + */ int (*update_status)(struct backlight_device *); - /* Return the current backlight brightness (accounting for power, - fb_blank etc.) */ + + /** + * @get_brightness: Return the current backlight brightness. + * + * The driver may implement this as a readback from the HW. + * This operation is optional and if not present then the current + * brightness property value is used. + * + * RETURNS: + * + * A brightness value which is 0 or a positive number. + * On failure a negative error code is returned. + */ int (*get_brightness)(struct backlight_device *); - /* Check if given framebuffer device is the one bound to this backlight; - return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */ - int (*check_fb)(struct backlight_device *, struct fb_info *); + + /** + * @check_fb: Check the framebuffer device. + * + * Check if given framebuffer device is the one bound to this backlight. + * This operation is optional and if not implemented it is assumed that the + * fbdev is always the one bound to the backlight. + * + * RETURNS: + * + * If info is NULL or the info matches the fbdev bound to the backlight return true. + * If info does not match the fbdev bound to the backlight return false. + */ + int (*check_fb)(struct backlight_device *bd, struct fb_info *info); }; /* This structure defines all the properties of a backlight */ -- cgit From cabf161335ca9fe695bb87469ed99be881cd08f5 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:28 +0200 Subject: backlight: backlight: Improve backlight_properties documentation Improve the documentation for backlight_properties and adapt it to kernel-doc style. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones --- include/linux/backlight.h | 96 +++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 85 insertions(+), 11 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 4ff60774ae22..3554aef008ea 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -117,28 +117,102 @@ struct backlight_ops { int (*check_fb)(struct backlight_device *bd, struct fb_info *info); }; -/* This structure defines all the properties of a backlight */ +/** + * struct backlight_properties - backlight properties + * + * This structure defines all the properties of a backlight. + */ struct backlight_properties { - /* Current User requested brightness (0 - max_brightness) */ + /** + * @brightness: The current brightness requested by the user. + * + * The backlight core makes sure the range is (0 to max_brightness) + * when the brightness is set via the sysfs attribute: + * /sys/class/backlight//brightness. + * + * This value can be set in the backlight_properties passed + * to devm_backlight_device_register() to set a default brightness + * value. + */ int brightness; - /* Maximal value for brightness (read-only) */ + + /** + * @max_brightness: The maximum brightness value. + * + * This value must be set in the backlight_properties passed to + * devm_backlight_device_register() and shall not be modified by the + * driver after registration. + */ int max_brightness; - /* Current FB Power mode (0: full on, 1..3: power saving - modes; 4: full off), see FB_BLANK_XXX */ + + /** + * @power: The current power mode. + * + * User space can configure the power mode using the sysfs + * attribute: /sys/class/backlight//bl_power + * When the power property is updated update_status() is called. + * + * The possible values are: (0: full on, 1 to 3: power saving + * modes; 4: full off), see FB_BLANK_XXX. + * + * When the backlight device is enabled @power is set + * to FB_BLANK_UNBLANK. When the backlight device is disabled + * @power is set to FB_BLANK_POWERDOWN. + */ int power; - /* FB Blanking active? (values as for power) */ - /* Due to be removed, please use (state & BL_CORE_FBBLANK) */ + + /** + * @fb_blank: The power state from the FBIOBLANK ioctl. + * + * When the FBIOBLANK ioctl is called @fb_blank is set to the + * blank parameter and the update_status() operation is called. + * + * When the backlight device is enabled @fb_blank is set + * to FB_BLANK_UNBLANK. When the backlight device is disabled + * @fb_blank is set to FB_BLANK_POWERDOWN. + * + * Backlight drivers should avoid using this property. It has been + * replaced by state & BL_CORE_FBLANK (although most drivers should + * use backlight_is_blank() as the preferred means to get the blank + * state). + * + * fb_blank is deprecated and will be removed. + */ int fb_blank; - /* Backlight type */ + + /** + * @type: The type of backlight supported. + * + * The backlight type allows userspace to make appropriate + * policy decisions based on the backlight type. + * + * This value must be set in the backlight_properties + * passed to devm_backlight_device_register(). + */ enum backlight_type type; - /* Flags used to signal drivers of state changes */ + + /** + * @state: The state of the backlight core. + * + * The state is a bitmask. BL_CORE_FBBLANK is set when the display + * is expected to be blank. BL_CORE_SUSPENDED is set when the + * driver is suspended. + * + * backlight drivers are expected to use backlight_is_blank() + * in their update_status() operation rather than reading the + * state property. + * + * The state is maintained by the core and drivers may not modify it. + */ unsigned int state; - /* Type of the brightness scale (linear, non-linear, ...) */ - enum backlight_scale scale; #define BL_CORE_SUSPENDED (1 << 0) /* backlight is suspended */ #define BL_CORE_FBBLANK (1 << 1) /* backlight is under an fb blank event */ + /** + * @scale: The type of the brightness scale. + */ + enum backlight_scale scale; }; struct backlight_device { -- cgit From 6f10cd124c44eea018672d5852708ca5dca4d06d Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:29 +0200 Subject: backlight: backlight: Improve backlight_device documentation Improve the documentation for backlight_device and adapt it to kernel-doc style. The updated documentation is more strict on how locking is used. With the update neither update_lock nor ops_lock may be used outside the backlight core. This restriction was introduced to keep the locking simple by keeping it in the core. It was verified that this documents the current state by renaming update_lock => bl_update_lock and ops_lock => bl_ops_lock. The rename did not reveal any uses outside the backlight core. The rename is NOT part of this patch. Signed-off-by: Sam Ravnborg Reviewed-by: Emil Velikov Reviewed-by: Daniel Thompson Reviewed-by: Jingoo Han Signed-off-by: Lee Jones --- include/linux/backlight.h | 72 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 49 insertions(+), 23 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 3554aef008ea..cf9977169fe8 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -14,21 +14,6 @@ #include #include -/* Notes on locking: - * - * backlight_device->ops_lock is an internal backlight lock protecting the - * ops pointer and no code outside the core should need to touch it. - * - * Access to update_status() is serialised by the update_lock mutex since - * most drivers seem to need this and historically get it wrong. - * - * Most drivers don't need locking on their get_brightness() method. - * If yours does, you need to implement it in the driver. You can use the - * update_lock mutex if appropriate. - * - * Any other use of the locks below is probably wrong. - */ - enum backlight_update_reason { BACKLIGHT_UPDATE_HOTKEY, BACKLIGHT_UPDATE_SYSFS, @@ -215,30 +200,71 @@ struct backlight_properties { enum backlight_scale scale; }; +/** + * struct backlight_device - backlight device data + * + * This structure holds all data required by a backlight device. + */ struct backlight_device { - /* Backlight properties */ + /** + * @props: Backlight properties + */ struct backlight_properties props; - /* Serialise access to update_status method */ + /** + * @update_lock: The lock used when calling the update_status() operation. + * + * update_lock is an internal backlight lock that serialise access + * to the update_status() operation. The backlight core holds the update_lock + * when calling the update_status() operation. The update_lock shall not + * be used by backlight drivers. + */ struct mutex update_lock; - /* This protects the 'ops' field. If 'ops' is NULL, the driver that - registered this device has been unloaded, and if class_get_devdata() - points to something in the body of that driver, it is also invalid. */ + /** + * @ops_lock: The lock used around everything related to backlight_ops. + * + * ops_lock is an internal backlight lock that protects the ops pointer + * and is used around all accesses to ops and when the operations are + * invoked. The ops_lock shall not be used by backlight drivers. + */ struct mutex ops_lock; + + /** + * @ops: Pointer to the backlight operations. + * + * If ops is NULL, the driver that registered this device has been unloaded, + * and if class_get_devdata() points to something in the body of that driver, + * it is also invalid. + */ const struct backlight_ops *ops; - /* The framebuffer notifier block */ + /** + * @fb_notif: The framebuffer notifier block + */ struct notifier_block fb_notif; - /* list entry of all registered backlight devices */ + /** + * @entry: List entry of all registered backlight devices + */ struct list_head entry; + /** + * @dev: Parent device. + */ struct device dev; - /* Multiple framebuffers may share one backlight device */ + /** + * @fb_bl_on: The state of individual fbdev's. + * + * Multiple fbdev's may share one backlight device. The fb_bl_on + * records the state of the individual fbdev. + */ bool fb_bl_on[FB_MAX]; + /** + * @use_count: The number of uses of fb_bl_on. + */ int use_count; }; -- cgit From d160fd4e918da33f5ffbcf005cd95888dbbe4f76 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:30 +0200 Subject: backlight: backlight: Document inline functions in backlight.h Add documentation for the inline functions in backlight.h Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones --- include/linux/backlight.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index cf9977169fe8..99381b5a289d 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -268,6 +268,10 @@ struct backlight_device { int use_count; }; +/** + * backlight_update_status - force an update of the backlight device status + * @bd: the backlight device + */ static inline int backlight_update_status(struct backlight_device *bd) { int ret = -ENOENT; @@ -361,6 +365,18 @@ extern int backlight_device_set_brightness(struct backlight_device *bd, unsigned #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev) +/** + * bl_get_data - access devdata + * @bl_dev: pointer to backlight device + * + * When a backlight device is registered the driver has the possibility + * to supply a void * devdata. bl_get_data() return a pointer to the + * devdata. + * + * RETURNS: + * + * pointer to devdata stored while registering the backlight device. + */ static inline void * bl_get_data(struct backlight_device *bl_dev) { return dev_get_drvdata(&bl_dev->dev); -- cgit From 2d15bb47f3331db979bd0a1987812ca1a3ff40c6 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:31 +0200 Subject: backlight: backlight: Document enums in backlight.h Add kernel-doc documentation for the backlight enums Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones --- include/linux/backlight.h | 72 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 99381b5a289d..1d56b34ff33c 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -14,26 +14,98 @@ #include #include +/** + * enum backlight_update_reason - what method was used to update backlight + * + * A driver indicates the method (reason) used for updating the backlight + * when calling backlight_force_update(). + */ enum backlight_update_reason { + /** + * @BACKLIGHT_UPDATE_HOTKEY: The backlight was updated using a hot-key. + */ BACKLIGHT_UPDATE_HOTKEY, + + /** + * @BACKLIGHT_UPDATE_SYSFS: The backlight was updated using sysfs. + */ BACKLIGHT_UPDATE_SYSFS, }; +/** + * enum backlight_type - the type of backlight control + * + * The type of interface used to control the backlight. + */ enum backlight_type { + /** + * @BACKLIGHT_RAW: + * + * The backlight is controlled using hardware registers. + */ BACKLIGHT_RAW = 1, + + /** + * @BACKLIGHT_PLATFORM: + * + * The backlight is controlled using a platform-specific interface. + */ BACKLIGHT_PLATFORM, + + /** + * @BACKLIGHT_FIRMWARE: + * + * The backlight is controlled using a standard firmware interface. + */ BACKLIGHT_FIRMWARE, + + /** + * @BACKLIGHT_TYPE_MAX: Number of entries. + */ BACKLIGHT_TYPE_MAX, }; +/** + * enum backlight_notification - the type of notification + * + * The notifications that is used for notification sent to the receiver + * that registered notifications using backlight_register_notifier(). + */ enum backlight_notification { + /** + * @BACKLIGHT_REGISTERED: The backlight device is registered. + */ BACKLIGHT_REGISTERED, + + /** + * @BACKLIGHT_UNREGISTERED: The backlight revice is unregistered. + */ BACKLIGHT_UNREGISTERED, }; +/** enum backlight_scale - the type of scale used for brightness values + * + * The type of scale used for brightness values. + */ enum backlight_scale { + /** + * @BACKLIGHT_SCALE_UNKNOWN: The scale is unknown. + */ BACKLIGHT_SCALE_UNKNOWN = 0, + + /** + * @BACKLIGHT_SCALE_LINEAR: The scale is linear. + * + * The linear scale will increase brightness the same for each step. + */ BACKLIGHT_SCALE_LINEAR, + + /** + * @BACKLIGHT_SCALE_NON_LINEAR: The scale is not linear. + * + * This is often used when the brightness values tries to adjust to + * the relative perception of the eye demanding a non-linear scale. + */ BACKLIGHT_SCALE_NON_LINEAR, }; -- cgit From 7ecdea4a0226f6c5cd0e86859d1b38cf17bc8529 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:32 +0200 Subject: backlight: generic_bl: Remove this driver as it is unused The backlight_bl driver required initialization using struct generic_bl_info. As there are no more references to this struct there is no users left. So it is safe to delete the driver. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones --- include/linux/backlight.h | 9 --------- 1 file changed, 9 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 1d56b34ff33c..d0f01dc3b98d 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -454,15 +454,6 @@ static inline void * bl_get_data(struct backlight_device *bl_dev) return dev_get_drvdata(&bl_dev->dev); } -struct generic_bl_info { - const char *name; - int max_intensity; - int default_intensity; - int limit_mask; - void (*set_bl_intensity)(int intensity); - void (*kick_battery)(void); -}; - #ifdef CONFIG_OF struct backlight_device *of_find_backlight_by_node(struct device_node *node); #else -- cgit From 9c4aa3118bab6f10904b7bc9bc34b501a083751b Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:33 +0200 Subject: backlight: backlight: Drop extern from prototypes No need to put "extern" in front of prototypes. While touching the prototypes adjust indent to follow the kernel style. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Signed-off-by: Lee Jones --- include/linux/backlight.h | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index d0f01dc3b98d..c1824426fc9e 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -417,23 +417,26 @@ static inline bool backlight_is_blank(const struct backlight_device *bd) bd->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK); } -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); -extern struct backlight_device *devm_backlight_device_register( - struct device *dev, const char *name, struct device *parent, - void *devdata, const struct backlight_ops *ops, - const struct backlight_properties *props); -extern void backlight_device_unregister(struct backlight_device *bd); -extern void devm_backlight_device_unregister(struct device *dev, - struct backlight_device *bd); -extern void backlight_force_update(struct backlight_device *bd, - enum backlight_update_reason reason); -extern int backlight_register_notifier(struct notifier_block *nb); -extern int backlight_unregister_notifier(struct notifier_block *nb); -extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type); +struct backlight_device * +backlight_device_register(const char *name, struct device *dev, void *devdata, + const struct backlight_ops *ops, + const struct backlight_properties *props); +struct backlight_device * +devm_backlight_device_register(struct device *dev, const char *name, + struct device *parent, void *devdata, + const struct backlight_ops *ops, + const struct backlight_properties *props); +void backlight_device_unregister(struct backlight_device *bd); +void devm_backlight_device_unregister(struct device *dev, + struct backlight_device *bd); +void backlight_force_update(struct backlight_device *bd, + enum backlight_update_reason reason); +int backlight_register_notifier(struct notifier_block *nb); +int backlight_unregister_notifier(struct notifier_block *nb); struct backlight_device *backlight_device_get_by_name(const char *name); -extern int backlight_device_set_brightness(struct backlight_device *bd, unsigned long brightness); +struct backlight_device *backlight_device_get_by_type(enum backlight_type type); +int backlight_device_set_brightness(struct backlight_device *bd, + unsigned long brightness); #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev) -- cgit From 2144d00ed0db28c764513080f95e4c49ea9133b0 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:36 +0200 Subject: backlight: backlight: Introduce backlight_get_brightness() 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 Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones --- include/linux/backlight.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index c1824426fc9e..26e89a8033f5 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -417,6 +417,25 @@ 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, -- cgit From 0f6a3256fd810eeca9c56cccafee46359d995138 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:42 +0200 Subject: backlight: backlight: Drop backlight_put() There are no external users of backlight_put(). Drop it and open code the two users in backlight.c. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones --- include/linux/backlight.h | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 26e89a8033f5..64f91324c911 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -388,16 +388,6 @@ static inline int backlight_disable(struct backlight_device *bd) return backlight_update_status(bd); } -/** - * backlight_put - Drop backlight reference - * @bd: the backlight device to put - */ -static inline void backlight_put(struct backlight_device *bd) -{ - if (bd) - put_device(&bd->dev); -} - /** * backlight_is_blank - Return true if display is expected to be blank * @bd: the backlight device -- cgit From b6539a11e807c531e51ff7ad9a25c3a1b6ff7340 Mon Sep 17 00:00:00 2001 From: Sam Ravnborg Date: Sun, 19 Jul 2020 10:07:43 +0200 Subject: backlight: backlight: Make of_find_backlight static There are no external users of of_find_backlight, as they have all changed to use the managed version. Make of_find_backlight static to prevent new external users. Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones --- include/linux/backlight.h | 6 ------ 1 file changed, 6 deletions(-) (limited to 'include/linux/backlight.h') diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 64f91324c911..614653e07e3a 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -477,14 +477,8 @@ of_find_backlight_by_node(struct device_node *node) #endif #if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE) -struct backlight_device *of_find_backlight(struct device *dev); struct backlight_device *devm_of_find_backlight(struct device *dev); #else -static inline struct backlight_device *of_find_backlight(struct device *dev) -{ - return NULL; -} - static inline struct backlight_device * devm_of_find_backlight(struct device *dev) { -- cgit