[Bug 221583] Lenovo 82KU: keyboard backlight works via Fn+Space but no kbd_backlight LED device exposed

[bugzilla-daemon@kernel.org]

https://bugzilla.kernel.org/show_bug.cgi?id=221583

--- Comment #23 from Rong Zhang (i@rong.moe) ---
(In reply to George from comment #22)
> Thank you for the explanation and for your patience. I have attached
> (dump_off.txt,dump_low.txt,dump_high.txt and dmesg_ec.txt) I hope i did it
> correctly.

Thanks. It did seem that 0x2A controlled the keyboard backlight brightness.

> I did try the unmodified patch and from what i can see the GNOME Quick
> Settings panel correctly displays all three states (Off, Low, High) but
> dotes not change the brightness of they keyboard.

Given that neither my patch nor manually writing to 0x2A worked, I guess the EC
needs an additional synchronization mechanism to really trigger a brightness
change from register writing.

> Pressing Fn + Space
> correctly triggers the OSD notification. i could upload a video if that's
> possible to show you what I can see. (is it possible to upload mp4?)

You don't need to upload a video. For now, I need the previous version of the
DSDT code where "Off and Low worked physically and the OSD appeared" to figure
out what triggers the brightness change.

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are watching the assignee of the bug.