[AMD Radeon HD 7500G][1002:990a] Unable to adjust brightness with radeon driver

[Po-Hsu Lin]

CID: 201307-13904 HP Pavilion 14

Steps:
1. Install 12.04.3 + update (3.8.0-33), boot to desktop
2. Adjust the brightness with hotkeys
3. Adjust the brightness with the brightness applet.

Expected results:
- Brightness could be controlled.

Actual result:
- The brightness level indicator will change with hotkeys, but brightness won't be changed, it can't be controlled by the brightness applet as well.

Debugging information:
$ ls /sys/class/backlight
acpi_video0 radeon_bl0

$ grep -r . /proc/acpi
/proc/acpi/button/lid/LID/state:state: open
grep: /proc/acpi/event: Permission denied
/proc/acpi/wakeup:Device S-state Status Sysfs node
/proc/acpi/wakeup:PB5 S5 *disabled pci:0000:00:05.0
/proc/acpi/wakeup:XPDV S5 *enabled pci:0000:03:00.0
/proc/acpi/wakeup:OHC1 S3 *enabled pci:0000:00:12.0
/proc/acpi/wakeup:OHC2 S3 *enabled pci:0000:00:13.0
/proc/acpi/wakeup:EHC1 S3 *enabled pci:0000:00:12.2
/proc/acpi/wakeup:EHC2 S3 *enabled pci:0000:00:13.2
/proc/acpi/wakeup:XHC0 S3 *enabled pci:0000:00:10.0
/proc/acpi/wakeup:KBC0 S3 *enabled pnp:00:06
/proc/acpi/wakeup:PS2M S3 *disabled pnp:00:07

$ cat /proc/version
Linux version 3.8.0-33-generic (buildd@toyol) (gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5) ) #48~precise1-Ubuntu SMP Thu Oct 24 16:28:06 UTC 2013

Note:
After the proprietary AMD video driver (fglrx-experimental-13) was installed, the brightness could be controlled normally.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: linux-image-3.8.0-33-generic 3.8.0-33.48~precise1
ProcVersionSignature: Ubuntu 3.8.0-33.48~precise1-generic 3.8.13.11
Uname: Linux 3.8.0-33-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version k3.8.0-33-generic.
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: amd64
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 1: Generic [HD-Audio Generic], device 0: ALC282 Analog [ALC282 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: ubuntu 1779 F.... pulseaudio
 /dev/snd/controlC0: ubuntu 1779 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'HDMI'/'HDA ATI HDMI at 0xf0344000 irq 46'
   Mixer name : 'ATI R6xx HDMI'
   Components : 'HDA:1002aa01,00aa0100,00100300'
   Controls : 7
   Simple ctrls : 1
Card0.Amixer.values:
 Simple mixer control 'IEC958',0
   Capabilities: pswitch pswitch-joined penum
   Playback channels: Mono
   Mono: Playback [on]
Card1.Amixer.info:
 Card hw:1 'Generic'/'HD-Audio Generic at 0xf0340000 irq 16'
   Mixer name : 'Realtek ALC282'
   Components : 'HDA:10ec0282,103c2169,00100003'
   Controls : 20
   Simple ctrls : 9
Date: Fri Nov 29 02:35:10 2013
HibernationDevice: RESUME=UUID=803edd91-ef6d-41c5-835c-65db44b01055
InstallationMedia: Ubuntu 12.04.3 LTS "Precise Pangolin" - Release amd64 (20130820.1)
IwConfig:
 eth0 no wireless extensions.

 lo no wireless extensions.
MachineType: Hewlett-Packard HP Pavilion 14 Notebook PC
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcFB: 0 radeondrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-33-generic root=UUID=e37c0bc3-93c5-4bcf-9e05-8d76ddb1455a ro quiet splash
RelatedPackageVersions:
 linux-restricted-modules-3.8.0-33-generic N/A
 linux-backports-modules-3.8.0-33-generic N/A
 linux-firmware 1.79.7
RfKill:

SourcePackage: linux-lts-raring
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/12/2013
dmi.bios.vendor: Insyde
dmi.bios.version: B.0C
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: 2169
dmi.board.vendor: Hewlett-Packard
dmi.board.version: 30.0F
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnInsyde:bvrB.0C:bd07/12/2013:svnHewlett-Packard:pnHPPavilion14NotebookPC:pvr088E100000005910000630100:rvnHewlett-Packard:rn2169:rvr30.0F:cvnHewlett-Packard:ct10:cvrChassisVersion:
dmi.product.name: HP Pavilion 14 Notebook PC
dmi.product.version: 088E100000005910000630100
dmi.sys.vendor: Hewlett-Packard

[Po-Hsu Lin (cypressyew)]

With "acpi_backlight=vendor" added into grub
brightness could be controlled by hotkeys and the applet

$ ls /sys/class/backlight
radeon_bl0

[penalvch (penalvch)]

Po-Hsu Lin, the Raring enablement stack is EoL as per https://wiki.ubuntu.com/Kernel/LTSEnablementStack . If you update to the latest, would this still be reproducible?

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]