Hi,

On 5/16/24 3:04 PM, Rafael J. Wysocki wrote:

CC Hans who has been doing the majority of the ACPI video work.

On Thu, May 16, 2024 at 2:43 PM Thomas Zimmermann [off-list ref] wrote:

quoted

Commit 2fd001cd3600 ("arch: Rename fbdev header and source files")
renames the video source files under arch/ such that they does not
refer to fbdev any longer. The new files named video.o conflict with
ACPI's video.ko module.

And surely nobody knew or was unable to check upfront that there was a
video.ko already in the kernel.

Sorry, but nack for this change. I very deliberately kept the module-name
as video when renaming the actual .c file from video.c to acpi_video.c
because many people pass drivers/video/acpi_video.c module arguments
on the kernel commandline using video.param=val .

Try e.g. doing a duckduckgo search for 1 off:

"video.only_lcd"
"video.allow_duplicates"
"video.brightness_switch_enabled"

And you will find a lot of hits. The last one is even documented as
being "video.brightness_switch_enabled" in the main kernel-parameters.txt
as well as separately:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/kernel-parameters.txt#n39
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/admin-guide/kernel-parameters.txt#n7152
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/firmware-guide/acpi/video_extension.rst#n118

https://wiki.archlinux.org/title/Lenovo_ThinkPad_X1_Carbon#Brightness_control

If you rename this module then peoples config will break for
a whole lot of users.

So lets not do that and lets rename the new module which is causing
the conflict in the first place instead.

Regards,

Hans