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Thread: 11.10 problems with VGA compatible controller (Acer travelmate)

  1. #11
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    I'm home for the weekend so I finally had the chance to try using an external monitor (and then read that you also suggested that )
    Here's what happens:

    if i boot with my grub config (nomodeset nosplash verbose) the display behaves exactly like the laptop display: low resolution, no possible configuration (the laptop display doesn't turn on though).
    I just booted without those options and now I finally have the option to configure the resolution and refresh rate of this screen (which is now 1280xH, 75Hz).
    So, yes. everything works well with an external monitor, given that the laptop monitor is off.
    The strange thing is that when I booted without my usual (nomodeset nosplash etc) options, the desktop background went back to the original one and the system asked me what kind of session I wanted to start.
    Besides that everything works fine though.

    You're suggesting the issue is brightness: I never was able to change it (not even on Ubuntu) so it's very probable. The fact is that when it's trying to boot, it's not like the laptop screen is just black: after a few seconds it turns off! Could it still be a brightness issue?

    I also tried to boot with the parameters you suggested: no luck.
    But now I have a lot of confusion and there's a lot of possible combinations of these parameters: when you suggest booting with acpi_backlight=vendor and so on, what other parameters should I keep and what should I remove from the previous configurations?

    My default set of parameters is:

    ro vga=775 nomodeset nosplash --verbose

    Thank you again, as always : )

  2. #12
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    Progress.

    I would suggest trying the following next. Boot into your system whatever way gets you there. Edit the file /etc/rc.local and add or edit the setpci command to read (make sure the command is above the "exit 0" command):
    Code:
    /usr/bin/setpci -s 00:02.0 F4.B=FF
    (note the change to add the full path to the setpci command and changing of value 00 to FF).
    Save the file.

    Boot again without "vga=775 nomodeset nosplash --verbose" and with no external monitor connected. Do you get a visible screen on the laptop lcd?

    If not, add the acpi_backlight=vendor kernel parameter to the mix. If you still get a blank screen on boot, try the brightness controls on the laptop, both up and down (I've seen bugs where they get reversed).

    Its looking like an acpi issue. The setpci command, if it works, will set the brightness value to full and hopefully increase the display. The acpi_backlight=vendor parameter instructs acpi to leave the brightness interface alone so that it can managed manually.

  3. #13
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)



    both with and without acpi_backlight=vendor the screen turns to black and then off... nothing seem to change on the surface!

    [ I'm also wondering.... my hardware configuration should be quite common, right? Why aren't there many posts about this problem out there? ]

  4. #14
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    Here is a related thread: http://ubuntuforums.org/showthread.p...ss%2Fbacklight. The solution there appears to be to prevent the video module from loading.

    What are the contents of your /sys/class/backlight directory? If you have two directories, including and intel one, the fix appears to be to blacklist the video module and boot with acpi_backlight=vendor.

  5. #15
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    My /sys/class/backlight folder contains only acpi_video0

    As suggested in that thread i tried typing

    Code:
    sudo bash -c "echo 2 > /sys/class/backlight/acpi_video0/brightness"
    also with values different than 2 (1,8,9) but nothing happened at all!

    as suggested in the other thread I typed
    Code:
    sudo modprobe -r video
    FATAL: Module video is in use.
    Last edited by sowdust; November 1st, 2011 at 03:24 PM.

  6. #16
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    Try booting with the acpi_backlight=vendor kernel parameter and see if you get another entry there. Might be intel_backlight, but lets confirm.

    If it does exist (intel_backlight), try echoing values in there to see if you can affect brightness.

    If that works, then:
    Code:
    sudo bash -c "echo 'blacklist video' >> /etc/modprobe.d/blacklist.conf"
    ...and reboot. This command will prevent it from loading.

  7. #17
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    with acpi_backlight=vendor option in /sys/class/backlight i get a folder named acer-wmi

    But if i try
    Code:
    sudo bash -c "echo 2 > /sys/class/backlight/acer-wmi/brightness"
    nothing changes (again, with values from 1 thru 9)

  8. #18
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    What are the contents of /sys/class/backlight/acer-wmi/max_brightness?

    With the acer_wmi interface, can you now try:
    Code:
    sudo setpci -s 00:02.0 F4.B=ff
    sudo setpci -s 00:02.0 F4.B=7f
    sudo setpci -s 00:02.0 F4.B=00
    ...to see if there is any change to the brightness.

    Also try:
    Code:
    xbacklight -set 50
    xbacklight -set 100
    ...you may need to install xbacklight from the repositories.

    And finally, do you now have a /sys/devices/platform/acer-wmi/backlight/acer-wmi/? Are there brightness files there and can you force a brightness change.

    If you have this working with the external monitor plugged in and the lcd off, the brightness controls might not work. Try adding:
    Code:
    echo 10 > /sys/class/backlight/acer-wmi/brightness
    into your /etc/rc.local file (before the exit 0) and rebooting without the external monitor plugged in.

    Another option might be to install openssh-server so that you can ssh from another machine and try adjusting the brightness controls remotely (instead of rebooting all the time)

    EDIT: One more thing to try - try booting with the following kernel parameters:
    Code:
    acpi_osi=Linux acpi_backlight=vendor
    Last edited by Toz; November 2nd, 2011 at 11:16 AM.

  9. #19
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    Edit:I forgot to mention I do not have the chance to use an external monitor right now.

    first thing i noticed is that booting with acpi_osi=linux and acpi_backlight=vendor made the "verbose" part of the booting process much better looking (smaller and correctly indented text)

    Quote Originally Posted by Toz View Post
    What are the contents of /sys/class/backlight/acer-wmi/max_brightness?
    9


    the sudo setpci -s command works:
    Code:
    sudo setpci -s 00:02.0 F4.B=ff
    makes it all black, while
    Code:
    sudo setpci -s 00:02.0 F4.B=0
    makes it very bright.
    But this works also without acpi_vendor and acpi_osi parameters, or, works also when in /sys/class/backlight there is onli acpi_video0


    Installed xbacklight:
    with both the booting configurations, I get a
    No outputs have backlight property

    I do have a /sys/devices/platform/acer-wmi/backlight/acer-wmi/

    with files such as actual brightness (was containing "3"). Tried to edit with a sudo command but didn't work.

    This is the content of my rc.local:

    Code:
    /usr/bin/setpci -s 00:02.0 F4.B=00
    echo 10 > /sys/class/backlight/acer-wmi/brightness
    exit 0
    Last edited by sowdust; November 2nd, 2011 at 07:37 PM.

  10. #20
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    Re: 11.10 problems with VGA compatible controller (Acer travelmate)

    Ok.
    Change /etc/rc.local to read:
    Code:
    /usr/bin/setpci -s 00:02.0 F4.B=0
    exit 0
    Then boot with "acpi_osi=Linux acpi_backlight=vendor" (no external monitor).

    Do you get a visible screen that you can change the resolution on?

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