Red Hat Bugzilla – Bug 483280
Radeon XPRESS 200M (RC410) - Gamma setting in xorg.conf not honored unless nomodeset in kernel
Last modified: 2009-12-18 02:45:07 EST
Created attachment 330494 [details]
Configuration file used for Xorg, with required gamma value.
Description of problem:
My screen needs a gamma setting of 2.08 to show colors properly - otherwise the output is annoyingly dark. This gamma value is the one reported by EDID, from what I can glean in the X server log.
When using modesetting (the default case), the value gets picked up from the conf file and shown in the log, but is not actually applied - the graphical screen is still too dark. Also the xgamma command does not work at all, even though it reports that the gamma value is set to the correct value.
By adding "nomodeset" to the kernel command line, the xorg.conf value is correctly applied, and the xgamma command works. However, this also results in DRI disabled, so it is not a good workaround.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Get a Radeon RC410 chipset to test
2. With kernel modesetting active, attempt to change gamma value (with xorg.conf or xgamma command)
Gamma value and/or execution of xgamma result in no visible change on the screen, even though values are correctly reported.
Gamma value should be immediately applied, regardless of the use of modesetting.
Workaround is to disable kernel modesetting on boot.
Created attachment 330495 [details]
Output of lspci -v
I can confirm this on a Radeon 9600XT. Gamma does nothing no matter how you set it. This is a problem with Quake 3, it displays really, really dark and moving the in-game slider does nothing. Same hardware as in 487432
Still present with:
Okay, as of:
... Gamma now seems to work. Sort of. The brightness slider in Quake 3 now works properly with modesetting enabled, but something weird has happened to the "xgamma" command line tool. Setting larger numbers makes the display *darker*, smaller numbers make it brighter. This is a change in previous behavior. I now have to set the gamma to 0.8 or so to get what I used to with 1.2. The gamma setting has become 1/gamma ? 1/1.2 comes out to 0.833333333...
I'm also seeing this problem with my Dell laptop (Radeon x300 card)
01:00.0 VGA compatible controller: ATI Technologies Inc M22 [Mobility Radeon X30
0] (prog-if 00 [VGA controller])
Subsystem: Dell Device 2003
Flags: bus master, fast devsel, latency 0, IRQ 16
Memory at d0000000 (32-bit, prefetchable) [size=128M]
I/O ports at de00 [size=256]
Memory at dfdf0000 (32-bit, non-prefetchable) [size=64K]
[virtual] Expansion ROM at dfd00000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel modules: radeon, radeonfb
xgamma appears to work but does not actually change the screen gamma. I would really like working gamma to be able to view photos properly (they all look too dark without it)
This message is a reminder that Fedora 10 is nearing its end of life.
Approximately 30 (thirty) days from now Fedora will stop maintaining
and issuing updates for Fedora 10. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
this bug will be closed as WONTFIX if it remains open with a Fedora
'version' of '10'.
Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version'
to a later Fedora version prior to Fedora 10's end of life.
Bug Reporter: Thank you for reporting this issue and we are sorry that
we may not be able to fix it before Fedora 10 is end of life. If you
would still like to see this bug fixed and are able to reproduce it
against a later version of Fedora please change the 'version' of this
bug to the applicable version. If you are unable to change the version,
please add a comment here and someone will do it for you.
Although we aim to fix as many bugs as possible during every release's
lifetime, sometimes those efforts are overtaken by events. Often a
more recent Fedora release includes newer upstream software that fixes
bugs or makes them obsolete.
The process we are following is described here:
Fedora 10 changed to end-of-life (EOL) status on 2009-12-17. Fedora 10 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.
If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version.
Thank you for reporting this bug and we are sorry it could not be fixed.