On Fri, Jul 18 2025 20:14:08 -0500, Mario Limonciello wrote:
OK, I think we need to do two things to figure out what's going on.
- Let's shift over to 6.16-rc6. Once we've got a handle on the situation
there we can iron out if there are other patches missing or this is also broken for you in 6.16. If it's not working as expected there either we need it fixed there first anyway.
Same behavior on 6.16-rc6: brightness is set to 0 (max 399000), minimally visible.
- The starting brightness I don't expect to be "0". We need to see what
values were read out from the firmware. There is a debugging message we can catch if you boot with drm.debug=0x106. Keep in mind you probably need to increase log_buf_len if your ring buffer is set too small too.
https://github.com/torvalds/linux/commit/4b61b8a390511a1864f26cc42bab72881e9...
PS: I would rather you add logs into a gist, pastebin or a bug somewhere if you can.
[ 3.210757] amdgpu 0000:03:00.0: [drm:amdgpu_dm_connector_late_register [amdgpu]] Backlight caps: min: 1000, max: 400000, ac 100, dc 32
full dmesg: https://termbin.com/o2q3