Re: [PATCH v3 0/4] cros_kbd_led_backlight: allow binding through cros_ec mfd device

From: Lee Jones
Date: Fri May 31 2024 - 11:35:43 EST


On Sun, 26 May 2024, Thomas Weißschuh wrote:

> 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(-)

Looks okay.

Does the platform patch need to be applied with the others?

--
Lee Jones [李琼斯]