Extend the cros_ec MFD device to also load cros_kbd_led_backlight when the EC reports EC_FEATURE_PWM_KEYB. As the driver can now be probed multiple times, some preparation in the LED core is necessary to avoid name collisions. Patch 1 is a general cleanup for the LED core. Patch 2 modifies the LED core to skip the default collision handling. Patch 3 adds the new probing logic to cros_kbd_led_backlight. Patch 4 wires up the driver to the cros_ec mfd devices. The helper keyboard_led_is_mfd_device is a bit iffy. But using match data doesn't work. * driver_data from platform_device_id is overwritten by the mfd platform data * Setting the driver_data in drivers/mfd/cros_ec_dev.c would expose the internals of cros_kbd_led_backlight Tested on a Framework 13 AMD, Firmware 3.05, and a Jinlon Chromebook. To: Lee Jones <lee@xxxxxxxxxx> To: Benson Leung <bleung@xxxxxxxxxxxx> To: Guenter Roeck <groeck@xxxxxxxxxxxx> To: Tzung-Bi Shih <tzungbi@xxxxxxxxxx> To: Pavel Machek <pavel@xxxxxx> Cc: chrome-platform@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: Dustin Howett <dustin@xxxxxxxxxx> Cc: Mario Limonciello <mario.limonciello@xxxxxxx> Cc: linux-leds@xxxxxxxxxxxxxxx Cc: Rajas Paranjpe <paranjperajas@xxxxxxxxx> Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> Changes in v3: - Avoid probing multiple times (Confirmed by Rajas) - Add Kconfig dependency on MFD_CROS_EC_DEV - Link to v2: https://lore.kernel.org/r/20240511-cros_ec-kbd-led-framework-v2-0-b20c48109e46@xxxxxxxxxxxxxx Changes in v2: - Fix build with CONFIG_MFD_CROS_EC_DEV=n (kernel test robot) - Split out mfd registration into own commit (Lee) - Simplify keyboard_led_is_mfd_device() with mfd_get_cell() - Link to v1: https://lore.kernel.org/r/20240505-cros_ec-kbd-led-framework-v1-1-bfcca69013d2@xxxxxxxxxxxxxx --- Thomas Weißschuh (4): leds: class: warn about name collisions earlier leds: add flag to avoid automatic renaming of led devices platform/chrome: cros_kbd_led_backlight: allow binding through mfd device mfd: cros_ec: Register keyboard backlight subdevice drivers/leds/led-class.c | 9 +++--- drivers/mfd/cros_ec_dev.c | 9 ++++++ drivers/platform/chrome/Kconfig | 2 +- drivers/platform/chrome/cros_kbd_led_backlight.c | 40 ++++++++++++++++++++++-- include/linux/leds.h | 1 + 5 files changed, 54 insertions(+), 7 deletions(-) --- base-commit: 6fbf71854e2ddea7c99397772fbbb3783bfe15b5 change-id: 20240505-cros_ec-kbd-led-framework-7e2e831bc79c Best regards, -- Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
