[PATCH v6 0/2] Backlight driver to control backlight behind Congatec Board Controller.

From: Petri Karhula via B4 Relay

Date: Fri Dec 05 2025 - 07:19:51 EST


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.


Signed-off-by: Petri Karhula <petri.karhula@xxxxxxxxxxx>
---
Changes in v6:
- No code changes, just collected tags.
- Link to v5: https://lore.kernel.org/r/20251204-cgbc-backlight-v5-0-26f1be6a69c3@xxxxxxxxxxx

Changes in v5:
- Added current and requested brightnesses to verification error message.
- Link to v4: https://lore.kernel.org/r/20251127-cgbc-backlight-v4-0-626523b7173d@xxxxxxxxxxx

Changes in v4:
- Factor out brightness read into a helper
- Set backlight_properties.scale to BACKLIGHT_SCALE_LINEAR
- Link to v3: https://lore.kernel.org/r/20251125-cgbc-backlight-v3-0-18ae42689411@xxxxxxxxxxx

Changes in v3:
- Fixed review comments and simplified the structure of the driver
- Link to v2: https://lore.kernel.org/r/20251119-cgbc-backlight-v2-0-4d4edd7ca662@xxxxxxxxxxx

Changes in v2:
- Separated Board Controller core driver change into its own patch
- Link to v1: https://lore.kernel.org/r/20251118-cgbc-backlight-v1-1-cc6ac5301034@xxxxxxxxxxx

---
Petri Karhula (2):
backlight: Add Congatec Board Controller (CGBC) backlight support
mfd: cgbc: Add support for backlight

drivers/mfd/cgbc-core.c | 1 +
drivers/video/backlight/Kconfig | 11 +++
drivers/video/backlight/Makefile | 1 +
drivers/video/backlight/cgbc_bl.c | 180 ++++++++++++++++++++++++++++++++++++++
4 files changed, 193 insertions(+)
---
base-commit: 7d0a66e4bb9081d75c82ec4957c50034cb0ea449
change-id: 20251118-cgbc-backlight-35c1109db0b8

Best regards,
--
Petri Karhula <petri.karhula@xxxxxxxxxxx>