linux-toradex.git/drivers/video/backlight/backlight.c, branch v5.11-rc2

backlight: backlight: Make of_find_backlight static

2020-07-20T09:27:11+00:00

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

backlight: backlight: Drop backlight_put()

2020-07-20T09:27:09+00:00

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

backlight: backlight: Add overview and update existing doc

2020-07-20T09:26:20+00:00

Add overview chapter to backlight.c.

Update existing kernel-doc to follow a more consistent style and drop
kernel-doc for deprecated functions.

Signed-off-by: Sam Ravnborg 
Reviewed-by: Daniel Thompson 
Reviewed-by: Emil Velikov 
Signed-off-by: Lee Jones

backlight: backlight: Refactor fb_notifier_callback()

2020-07-20T09:17:04+00:00

Increase readability of fb_notifier_callback() by removing
a few indent levels.

No functional change.

Signed-off-by: Sam Ravnborg 
Reviewed-by: Daniel Thompson 
Reviewed-by: Emil Velikov 
Signed-off-by: Lee Jones

backlight: backlight: Supply description for function args in existing Kerneldocs

2020-07-06T07:11:42+00:00

Kerneldoc syntax is used, but not complete.  Descriptions required.

Prevents warnings like:

 drivers/video/backlight/backlight.c:329: warning: Function parameter or member 'reason' not described in 'backlight_force_update'
 drivers/video/backlight/backlight.c:354: warning: Function parameter or member 'props' not described in 'backlight_device_register'

Cc: Bartlomiej Zolnierkiewicz 
Cc: Jamey Hicks 
Cc: Andrew Zabolotny 
Signed-off-by: Lee Jones 
Reviewed-by: Daniel Thompson 
Reviewed-by: Sam Ravnborg 
Signed-off-by: Lee Jones

backlight: Add backlight_device_get_by_name()

2020-05-11T06:39:16+00:00

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 
Reviewed-by: Sam Ravnborg 
Reviewed-by: Daniel Thompson 
Acked-by: Jingoo Han 
Signed-off-by: Lee Jones

backlight: Expose brightness curve type through sysfs

2019-09-02T14:55:03+00:00

Backlight brightness curves can have different shapes. The two main
types are linear and non-linear curves. The human eye doesn't
perceive linearly increasing/decreasing brightness as linear (see
also 88ba95bedb79 "backlight: pwm_bl: Compute brightness of LED
linearly to human eye"), hence many backlights use non-linear (often
logarithmic) brightness curves. The type of curve currently is opaque
to userspace, so userspace often uses more or less reliable heuristics
(like the number of brightness levels) to decide whether to treat a
backlight device as linear or non-linear.

Export the type of the brightness curve via the new sysfs attribute
'scale'. The value of the attribute can be 'linear', 'non-linear' or
'unknown'. For devices that don't provide information about the scale
of their brightness curve the value of the 'scale' attribute is 'unknown'.

Signed-off-by: Matthias Kaehlcke 
Reviewed-by: Daniel Thompson 
Signed-off-by: Lee Jones

Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"

2019-06-12T18:29:40+00:00

This reverts commit 994efacdf9a087b52f71e620b58dfa526b0cf928.

The justification is that if hw blanking fails (i.e. fbops->fb_blank)
fails, then we still want to shut down the backlight. Which is exactly
_not_ what fb_blank() does and so rather inconsistent if we end up
with different behaviour between fbcon and direct fbdev usage. Given
that the entire notifier maze is getting in the way anyway I figured
it's simplest to revert this not well justified commit.

v2: Add static inline to the dummy version.

Cc: Richard Purdie 
Signed-off-by: Daniel Vetter 
Reviewed-by: Sam Ravnborg 
Reviewed-by: Maarten Lankhorst 
Acked-by: Daniel Thompson 
Cc: Lee Jones 
Cc: Daniel Thompson 
Cc: Jingoo Han 
Cc: Bartlomiej Zolnierkiewicz 
Cc: Daniel Vetter 
Cc: Hans de Goede 
Cc: Yisheng Xie 
Cc: linux-fbdev@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-25-daniel.vetter@ffwll.ch

treewide: Add SPDX license identifier for more missed files

2019-05-21T08:50:45+00:00

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

video: backlight: Add devres versions of of_find_backlight

2018-01-29T15:34:53+00:00

Add devm_of_find_backlight and the corresponding release
function because some drivers use devres versions of functions
for acquiring device resources.

Acked-by: Daniel Thompson 
Reviewed-by: Noralf Trønnes 
Reviewed-by: Sean Paul 
Signed-off-by: Meghana Madhyastha 
Signed-off-by: Sean Paul 
Link: https://patchwork.freedesktop.org/patch/msgid/021f8fecfa3f374dc5dcb70fb07a6f6b019bea7b.1516810725.git.meghana.madhyastha@gmail.com