90 Commits
Author SHA1 Message Date
Petri KarhulaandLee Jones b516456e9f backlight: Add Congatec Board Controller (CGBC) backlight support
This driver provides backlight brightness control through the Linux
backlight subsystem. It communicates with the board controller to
adjust LCD backlight using PWM signals. Communication is done
through Congatec Board Controller core driver.

Tested-by: Thomas Richard <thomas.richard@bootlin.com>
Reviewed-by: Thomas Richard <thomas.richard@bootlin.com>
Reviewed-by: Daniel Thompson (RISCstar) <danielt@kernel.org>
Signed-off-by: Petri Karhula <petri.karhula@novatron.fi>
Link: https://patch.msgid.link/20251205-cgbc-backlight-v6-1-e4175b0bf406@novatron.fi
Signed-off-by: Lee Jones <lee@kernel.org>
2026-01-08 11:15:00 +00:00
Junjie CaoandLee Jones 147b38a5ad backlight: aw99706: Add support for Awinic AW99706 backlight
Add support for Awinic AW99706 backlight, which can be found in
tablet and notebook backlight, one case is the Lenovo Legion Y700
Gen4. This driver refers to the official datasheets and android
driver, they can be found in [1].

[1] https://www.awinic.com/en/productDetail/AW99706QNR

Signed-off-by: Junjie Cao <caojunjie650@gmail.com>
Tested-by: Pengyu Luo <mitltlatltl@gmail.com>
Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
Reviewed-by: Daniel Thompson (RISCstar) <danielt@kernel.org>
Link: https://patch.msgid.link/20251109032240.3422503-3-caojunjie650@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
2025-11-25 12:54:14 +00:00
Dr. David Alan GilbertandLee Jones dfc034a049 backlight: pcf50633-backlight: Remove unused driver
The pcf50633 was used as part of the OpenMoko devices but
the support for its main chip was recently removed in:
commit 61b7f8920b ("ARM: s3c: remove all s3c24xx support")

See https://lore.kernel.org/all/Z8z236h4B5A6Ki3D@gallifrey/

Remove it.

Signed-off-by: "Dr. David Alan Gilbert" <linux@treblig.org>
Link: https://lore.kernel.org/r/20250311014959.743322-8-linux@treblig.org
Signed-off-by: Lee Jones <lee@kernel.org>
2025-03-14 11:36:33 +00:00
Nick ChanandLee Jones ea45d216dd backlight: apple_dwi_bl: Add Apple DWI backlight driver
Add driver for backlight controllers attached via Apple DWI 2-wire
interface, which is found on some Apple iPhones, iPads and iPod touches
with a LCD display.

Although there is an existing apple_bl driver, it is for backlight
controllers on Intel Macs attached via PCI, which is completely different
from the Samsung-derived DWI block.

Reviewed-by: "Daniel Thompson (RISCstar)" <danielt@kernel.org>
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Link: https://lore.kernel.org/r/20250214040306.16312-3-towinchenmi@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
2025-02-20 15:14:29 +00:00
Patrick GanstererandLee Jones b72755f5b5 backlight: Add new lm3509 backlight driver
This is a general driver for LM3509 backlight chip of TI.
LM3509 is High Efficiency Boost for White LEDs and/or OLED Displays with
Dual Current Sinks. This driver supports OLED/White LED select, brightness
control and sub/main control.
The datasheet can be found at http://www.ti.com/product/lm3509.

Signed-off-by: Patrick Gansterer <paroga@paroga.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20240526105136.721529-3-paroga@paroga.com
Signed-off-by: Lee Jones <lee@kernel.org>
2024-05-31 15:12:13 +01:00
Duje MihanovićandLee Jones a5554f1b5b backlight: Add Kinetic KTD2801 Backlight support
KTD2801 is a LED backlight driver IC found in samsung,coreprimevelte.
The brightness can be set using PWM or the ExpressWire protocol. Add
support for the KTD2801.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Duje Mihanović <duje.mihanovic@skole.hr>
Link: https://lore.kernel.org/r/20240125-ktd2801-v5-4-e22da232a825@skole.hr
Signed-off-by: Lee Jones <lee@kernel.org>
2024-03-07 08:45:16 +00:00
Linus Torvalds 21c91bb936 Merge tag 'backlight-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight
Pull backlight updates from Lee Jones:
 "New Drivers:
   - Add support for Monolithic Power Systems MP3309C WLED Step-up Converter

  Fix-ups:
   - Use/convert to new/better APIs/helpers/MACROs instead of
     hand-rolling implementations
   - Device Tree Binding updates
   - Demote non-kerneldoc header comments
   - Improve error handling; return proper error values, simplify, avoid
     duplicates, etc
   - Convert over to the new (kinda) GPIOD API

  Bug Fixes:
   - Fix uninitialised local variable"

* tag 'backlight-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: hx8357: Convert to agnostic GPIO API
  backlight: ili922x: Add an error code check in ili922x_write()
  backlight: ili922x: Drop kernel-doc for local macros
  backlight: mp3309c: Fix uninitialized local variable
  backlight: pwm_bl: Use dev_err_probe
  backlight: mp3309c: Add support for MPS MP3309C
  dt-bindings: backlight: mp3309c: Remove two required properties
2024-01-18 16:53:35 -08:00
Matthew Wilcox (Oracle)andHelge Deller d9f25b59ed fbdev: Remove support for Carillo Ranch driver
As far as anybody can tell, this product never shipped.  If it did,
it shipped in 2007 and nobody has access to one any more.  Remove the
fbdev driver and the backlight driver.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2024-01-12 12:38:37 +01:00
Flavio SuligoiandLee Jones 2e914516a5 backlight: mp3309c: Add support for MPS MP3309C
The Monolithic Power (MPS) MP3309C is a WLED step-up converter, featuring a
programmable switching frequency to optimize efficiency.
The brightness can be controlled either by I2C commands (called "analog"
mode) or by a PWM input signal (PWM mode).
This driver supports both modes.

For DT configuration details, please refer to:
- Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml

The datasheet is available at:
- https://www.monolithicpower.com/en/mp3309c.html

Signed-off-by: Flavio Suligoi <f.suligoi@asem.it>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20231116105319.957600-3-f.suligoi@asem.it
Signed-off-by: Lee Jones <lee@kernel.org>
2023-11-23 14:54:32 +00:00
Jianhua LuandLee Jones f8449c8f73 backlight: ktz8866: Add support for Kinetic KTZ8866 backlight
Add support for Kinetic KTZ8866 backlight, which is used in
Xiaomi tablet, Mi Pad 5 series. This driver lightly based on
downstream implementation [1].
[1] https://github.com/MiCode/Xiaomi_Kernel_OpenSource/blob/elish-r-oss/drivers/video/backlight/ktz8866.c

Signed-off-by: Jianhua Lu <lujianhua000@gmail.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230120155018.15376-2-lujianhua000@gmail.com
2023-02-22 10:55:28 +00:00
Arnd BergmannandLee Jones 744fc2dada backlight: Remove pxa tosa support
The PXA tosa machine was removed, so this backlight driver is no
longer needed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230105134622.254560-10-arnd@kernel.org
2023-02-22 10:55:27 +00:00
ChiaEn WuandLee Jones e7647de058 video: backlight: mt6370: Add MediaTek MT6370 support
MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger
with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight
driver, display bias voltage supply, one general purpose LDO, and the
USB Type-C & PD controller complies with the latest USB Type-C and PD
standards.

Add support for the MediaTek MT6370 backlight driver.
It controls 4 channels of 8 series WLEDs in
2048 (only for MT6370/MT6371) / 16384 (only for MT6372)
current steps (30 mA) in exponential or linear mapping curves.

Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: ChiaEn Wu <chiaen_wu@richtek.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20220830034042.9354-11-peterwu.pub@gmail.com
2022-09-08 08:50:57 +01:00
ChiYuan HuangandLee Jones 190ccab318 backlight: rt4831: Adds support for Richtek RT4831 backlight
Adds support for Richtek RT4831 backlight.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2021-05-19 15:52:25 +01:00
Linus WalleijandLee Jones 5317f37e48 backlight: Add Kinetic KTD253 backlight driver
The Kinetic KTD253 backlight driver is controlled with a
single GPIO line, but still supports a range of brightness
settings by sending fast pulses on the line.

This is based off the source code release for the Samsung
GT-S7710 mobile phone.

Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-08-28 11:48:04 +01:00
Sam RavnborgandLee Jones 7ecdea4a02 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 <sam@ravnborg.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-20 10:26:08 +01:00
Linus WalleijandLee Jones e994734fdc backlight: Delete the OT200 backlight driver
This driver has no in-kernel users. The device can only be populated
by board files since it does not support device tree nor ACPI,
and nothing in the kernel creates a device named "ot200-backlight".

This driver has been in the kernel since 2012. If it is used by
out-of-tree code that code should have been upstreamed by now,
it's been 8 years.

It uses the idiomatic forked GPIO of the CS5535 which combines
pin control and GPIO into its private custom interface, which
causes me a headache because that is not how we do things these
days: we creates separate pin control and GPIO drivers.

Delete this unused driver.

Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-07-01 10:55:56 +01:00
Tomi ValkeinenandTony Lindgren ae232e45ac backlight: add led-backlight driver
This patch adds a led-backlight driver (led_bl), which is similar to
pwm_bl except the driver uses a LED class driver to adjust the
brightness in the HW. Multiple LEDs can be used for a single backlight.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2020-02-19 13:15:39 -08:00
Kiran GundaandLee Jones 51c0ddc758 backlight: qcom-wled: Rename pm8941-wled.c to qcom-wled.c
pm8941-wled.c driver is supporting the WLED peripheral
on pm8941. Rename it to qcom-wled.c so that it can support
WLED on multiple PMICs.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2019-11-01 08:03:29 +00:00
Krzysztof KozlowskiandLee Jones e1c9f2eaa0 backlight: Remove ld9040 driver
The driver for LD9040 AMOLED LCD panel was superseded with DRM driver
panel-samsung-ld9040.c.  It does not support DeviceTree and respective
possible user (Exynos4210 Universal C210) is DeviceTree-only and uses
DRM version of driver.

Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-10-09 02:59:20 -07:00
Krzysztof KozlowskiandLee Jones 64c03ab0d5 backlight: Remove s6e63m0 driver
The driver for S6E63M0 AMOLED LCD panel is not used.  It does not
support DeviceTree and respective possible users (S5Pv210 Aquila and
Goni boards) are DeviceTree-only.

Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-10-09 02:59:09 -07:00
Felix BrackandLee Jones e943da471a backlight: otm3225a: Add support for ORISE OTM3225A LCD SoC
This patch adds a LCD driver supporting the OTM3225A LCD SoC
from ORISE Technology. This device can drive TFT LC panels having a
resolution of 240x320 pixels. After initializing the OTM3225A using
it's SPI interface it switches to use 16-bib RGB as external
display interface.

Signed-off-by: Felix Brack <fb@ltec.ch>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-04-30 10:50:44 +01:00
Andrey SmirnovandLee Jones 6552d31410 backlight: Add RAVE SP backlight driver
This driver provides access to RAVE SP backlight control
functionality.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-04-30 10:50:43 +01:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Olimpiu DejeuandLee Jones e739c5bb20 backlight: Add support for Arctic Sand LED backlight driver chips
This driver provides support for the Arctic Sand arc2c0608 chip,
and provides a framework to support future devices.

Signed-off-by: Olimpiu Dejeu <olimpiu@arcticsand.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2017-04-25 09:22:23 +01:00
Bjorn AnderssonandLee Jones 7ddbc2423c backlight: pm8941-wled: Move PM8941 WLED driver to backlight
The Qualcomm PM8941 WLED block is used for backlight and should therefor
be in the backlight framework and not in the LED framework. This moves
the driver and adapts to the backlight api instead.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-08-25 08:41:56 +01:00