Public bug reported:
A recent update to 5.15.0-41 results in my laptop screen (Dell Precision
7520) being unable to come up to full brightness. I have verified that I
can revert to 5.13.0-52 and the problem is not there. I looked at
/sys/class/backlight/nv_backlight/max_brightness which lists 1023 in the
newer kernel and 100 in the older one. I have verified that changing the
brightness manually does change
/sys/class/backlight/nv_backlight/brightness, all the way up to 1023,
but it's just not enough... the screen is still very dim. The other
screen (standalone monitor through docking station) on a two-headed
display is fine. I tried to write 100 into max_brightness but of course,
the "file" is read-only.
** Affects: linux-hwe-5.15 (Ubuntu)
Importance: Undecided
Status: New
** Package changed: linux-signed-hwe-5.15 (Ubuntu) => linux-hwe-5.15
(Ubuntu)
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux-signed-hwe-5.15 in Ubuntu.
https://bugs.launchpad.net/bugs/1981727
Title:
kernel 5.15.0-41 update results in dim screen (5.13.0-52 OK)
Status in linux-hwe-5.15 package in Ubuntu:
New
Bug description:
A recent update to 5.15.0-41 results in my laptop screen (Dell
Precision 7520) being unable to come up to full brightness. I have
verified that I can revert to 5.13.0-52 and the problem is not there.
I looked at /sys/class/backlight/nv_backlight/max_brightness which
lists 1023 in the newer kernel and 100 in the older one. I have
verified that changing the brightness manually does change
/sys/class/backlight/nv_backlight/brightness, all the way up to 1023,
but it's just not enough... the screen is still very dim. The other
screen (standalone monitor through docking station) on a two-headed
display is fine. I tried to write 100 into max_brightness but of
course, the "file" is read-only.
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux-hwe-5.15/+bug/1981727/+subscriptions
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
