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masterme120

Member

Registered: 2014-09-22

Posts: 3

[Solved] Backlight stays off after resume on HP Pavilion g7

After resuming from standby, my HP Pavilion g7 continues correctly, except the backlight on the display doesn't turn back on.  I can still enter commands, however, and have tried writing to the file

/sys/class/backlight/radeon_bl0/brightness

along with

vbetool post

and

setpci -s 00:01.0 F4.B=00

Additionally, I have tried various bootflags including "nomodeset," which doesn't help and causes my screen to be corrupted, different values for "acpi_osi," and "acpi_backlight."  Nothing has worked so far.  I suspect that it's related to KMS, because the backlight occasionally stays off after the mode changes on boot, but the lack of difference with "nomodeset" seems to contradict that.  Any advice or suggestions would be very welcome.

Output of lspci:

00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Root Complex
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Trinity [Radeon HD 7640G]
00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Trinity HDMI Audio Controller
00:04.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Root Port
00:10.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB XHCI Controller (rev 03)
00:10.1 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB XHCI Controller (rev 03)
00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode]
00:12.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB OHCI Controller (rev 11)
00:12.2 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 11)
00:13.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB OHCI Controller (rev 11)
00:13.2 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 11)
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 14)
00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD] FCH Azalia Controller (rev 01)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 11)
00:14.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] FCH PCI Bridge (rev 40)
00:15.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Hudson PCI to PCI bridge (PCIE port 0)
00:15.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Hudson PCI to PCI bridge (PCIE port 1)
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 0
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 5
02:00.0 Network controller: Qualcomm Atheros AR9485 Wireless Network Adapter (rev 01)
04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5229 PCI Express Card Reader (rev 01)
05:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 05)

Output of "systool -v -c backlight":

Class = "backlight"

  Class Device = "radeon_bl0"
  Class Device path = "/sys/devices/pci0000:00/0000:00:01.0/drm/card0/card0-LVDS-1/radeon_bl0"
    actual_brightness   = "60"
    bl_power            = "0"
    brightness          = "60"
    max_brightness      = "255"
    type                = "raw"
    uevent              = 

    Device = "card0-LVDS-1"
    Device path = "/sys/devices/pci0000:00/0000:00:01.0/drm/card0/card0-LVDS-1"
      dpms                = "On"
      edid                = 
      enabled             = "enabled"
      modes               = "1600x900
1600x900
1440x900
1280x854
1280x800
1280x720
1152x768
1024x768
800x600
848x480
720x480
640x480"
      status              = "connected"
      uevent              = 

Last edited by masterme120 (2014-09-26 19:15:33)

archie0

Member

Registered: 2012-02-26

Posts: 144

Re: [Solved] Backlight stays off after resume on HP Pavilion g7

https://bbs.archlinux.org/viewtopic.php?id=170547
https://bugs.freedesktop.org/show_bug.cgi?id=42960

Bug.

Suspend works fine on the closed driver though.

Edit:
Adding acpi_sleep=s3_bios,s3_mode to boot parameters seems to fix it for some people, but it only works on BIOS installations (!=UEFI).

Last edited by archie0 (2014-09-23 08:28:59)

masterme120

Member

Registered: 2014-09-22

Posts: 3

Re: [Solved] Backlight stays off after resume on HP Pavilion g7

Thanks for the advice!  After installing Catalyst, suspend works properly.