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[Alex Wijnstra <alex.wijnstra@xxxxxxxxx>]

Bug reported:
https://bugs.launchpad.net/ubuntu/+bug/1229252

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https://bugs.launchpad.net/bugs/1047483

Title:
  Ubuntu 12.10 Intel GMA4500M Display is blank upon bootup

Status in “linux” package in Ubuntu:
  Incomplete

Bug description:
   kubuntu / ubuntu 12.10 Intel GMA 4500M Black screen problem

  Installed the latest Kubuntu 12.10 on my Acer Aspire 4736Z laptop.
  However, the display is blank/black. The OS seems to have started
  correctly (keystrokes result in expected results, albeit flying blind)
  but only display is blank.

  The video adapter is Intel GMA4500M chip.

  This has been the case with (k)ubuntu 12.04 and 11.10 too. I remember
  the same laptop used to work just fine earlier (9.10 probably?)

  Google search led me to the following forums threads:
  http://ubuntuforums.org/showthread.php?t=1237873
  http://forums.gentoo.org/viewtopic-t-892206-start-0.html

  User cach0rr0 on the Gentoo forum mentions that setting
  /sys/class/backlight/acpi_video0/brightness to value 8 and rebooting
  immediately (say Ctrl-Alt-Del) retains the value and the display works
  fine. There should not be a power off/on sequence in between, since
  that destroys the value we have written into the register.

  So, I thought I could automate the same

  I modified my /etc/rc.local to detect the setting and if "wrong" set
  it to 8 and reboot. If the value is 8, the system completes the bootup
  and is ready for user login.

  The only "problem" with this trivial fix is that when powering on the
  laptop, it reboots automatically once.

  Suspend/Resume seems to work fine for me.

  
  catroot@asp4736-k1210:~# cat /etc/rc.local
  #!/bin/sh -e
  #
  # rc.local
  #
  # This script is executed at the end of each multiuser runlevel.
  # Make sure that the script will "exit 0" on success or any other
  # value on error.
  #
  # In order to enable or disable this script just change the execution
  # bits.
  #
  # By default this script does nothing.

  d=`date`
  bv=`cat /sys/class/backlight/acpi_video0/brightness`
  if [ $bv != "8" ];then
    echo 8 >/sys/class/backlight/acpi_video0/brightness
    echo "$d: acpi_video0 brightness is $bv so rebooting" >>/var/log/acpi_brightness.txt
    reboot
  else
    echo "$d: acpi_video0 brightness is $bv" >> >>/var/log/acpi_brightness.txt
  fi
  exit 0

  root@asp4736-k1210:~# lspci

  00:00.0 Host bridge: Intel Corporation Mobile 4 Series Chipset Memory Controller Hub (rev 09)
  00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 09)
  00:02.1 Display controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 09)
  00:1a.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 (rev 03)
  00:1a.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 (rev 03)
  00:1a.7 USB controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 (rev 03)
  00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)
  00:1c.0 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 1 (rev 03)
  00:1c.1 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 2 (rev 03)
  00:1c.2 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 3 (rev 03)
  00:1c.4 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 5 (rev 03)
  00:1d.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 (rev 03)
  00:1d.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 (rev 03)
  00:1d.2 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 (rev 03)
  00:1d.7 USB controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 (rev 03)
  00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev 93)
  00:1f.0 ISA bridge: Intel Corporation ICH9M LPC Interface Controller (rev 03)
  00:1f.2 SATA controller: Intel Corporation 82801IBM/IEM (ICH9M/ICH9M-E) 4 port SATA Controller [AHCI mode] (rev 03)
  00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev 03)
  00:1f.6 Signal processing controller: Intel Corporation 82801I (ICH9 Family) Thermal Subsystem (rev 03)
  04:00.0 Network controller: Atheros Communications Inc. AR928X Wireless Network Adapter (PCI-Express) (rev 01)
  05:00.0 Ethernet controller: Atheros Communications Inc. AR8121/AR8113/AR8114 Gigabit or Fast Ethernet (rev b0)
  07:00.0 System peripheral: JMicron Technology Corp. SD/MMC Host Controller
  07:00.2 SD Host controller: JMicron Technology Corp. Standard SD Host Controller
  07:00.3 System peripheral: JMicron Technology Corp. MS Host Controller
  07:00.4 System peripheral: JMicron Technology Corp. xD Host Controller
  root@asp4736-k1210:~#

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