kernel/linux.git/drivers/video/backlight/backlight.c, branch linux-4.20.y

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

video: backlight: Add of_find_backlight helper in backlight.c

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

Add of_find_backlight, a helper function which is a generic version of tinydrm_of_find_backlight that can be used by other drivers to avoid repetition of code and simplify things. Acked-by: Daniel Thompson Reviewed-by: Noralf Trønnes Reviewed-by: Sean Paul Reviewed-by: Thierry Reding Signed-off-by: Meghana Madhyastha Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/116d160ba78be2e6dcbdcb6855622bce67da9472.1516810725.git.meghana.madhyastha@gmail.com

backlight: Report error on failure

2017-05-30T08:27:53+00:00

It is possible to update the backlight power and the brightness using the sysfs and on writing it either returns the count or if the callback function does not exist then returns the error code 'ENXIO'. We have a situation where the userspace client is writing to the sysfs to update the power and since the callback function exists the client receives the return value as count and considers the operation to be successful. That is correct as the write to the sysfs was successful. But there is no way to know if the actual operation was done or not. backlight_update_status() returns the error code if it fails. Pass that to the userspace client who is trying to update the power so that the client knows that the operation failed. Signed-off-by: Sudip Mukherjee Acked-by: Daniel Thompson Signed-off-by: Lee Jones

video / backlight: remove the backlight_device_registered API

2016-05-04T21:41:14+00:00

Since we will need the backlight_device_get_by_type API, we can use it instead of the backlight_device_registered API whenever necessary so remove the backlight_device_registered API. Signed-off-by: Aaron Lu Acked-by: Jingoo Han Signed-off-by: Rafael J. Wysocki

video / backlight: add two APIs for drivers to use

2016-05-04T21:41:14+00:00

It is useful to get the backlight device's pointer and use it to set backlight in some cases(the following patch will make use of it) so add the two APIs and export them. Signed-off-by: Aaron Lu Acked-by: Jingoo Han Signed-off-by: Rafael J. Wysocki

backlight: Show brightness even if get_brightness is not implemented

2014-06-23T12:26:02+00:00

Many implementations of get_brightness operation returns only value of props.brightness field. This change makes such implementations unnecessary. Acked-by: Jingoo Han Signed-off-by: Andrzej Hajda Signed-off-by: Lee Jones

backlight: Add backlight device (un)registration notification

2014-05-26T23:29:01+00:00

Some firmware drivers, ie acpi-video want to get themselves out of the way (in some cases) when their also is a raw backlight device available. Due to module loading ordering being unknown, acpi-video cannot be certain that the backlight_device_registered(BACKLIGHT_RAW) it does for this is the final verdict wrt there being a BACKLIGHT_RAW device. By adding notification acpi-video can listen for backlight devices showing up after it has loaded, and unregister its backlight device if desired. Signed-off-by: Hans de Goede Acked-by: Jingoo Han Signed-off-by: Rafael J. Wysocki

Merge tag 'backlight-for-linus-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

2014-04-10T15:52:35+00:00

Pull backlight changes from Lee Jones: - core: call put_device() instead of kfree() - gpio-backlight: add DT support - lm3639_bl driver: use managed resources * tag 'backlight-for-linus-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight: backlight: lm3639: Use devm_backlight_device_register() backlight: gpio-backlight: Add DT support backlight: core: Replace kfree with put_device

backlight: core: Replace kfree with put_device

2014-04-08T12:20:39+00:00

As per the comments on device_register, we shouldn't call kfree() right after a device_register() failure. Instead call put_device(), which in turn will call bl_device_release resulting in a kfree to the full structure. Signed-off-by: Levente Kurusa Acked-by: Jingoo Han Signed-off-by: Lee Jones

backlight: update backlight status when necessary

2014-04-03T23:21:09+00:00

We don't have to update a backlight status every time a blanking or unblanking event comes because the backlight status may have already been what we want. Another thought is that one backlight device may be shared by multiple framebuffers. We don't hope blanking one of the framebuffers may turn the backlight off for all the other framebuffers, since they are likely being active to display something. This patch makes the backlight status be updated only when the relevant backlight device's use count changes from zero to one or from one to zero. Signed-off-by: Liu Ying Cc: Jingoo Han Cc: Jean-Christophe PLAGNIOL-VILLARD Cc: Tomi Valkeinen Cc: Jani Nikula Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds