Acer Aspire, Intel Video, No Backlight

[MikeCO]

I've Googled this repeatedly, and found some help, but still stuck with a weird bug.

Acer Aspire 5336
Intel Mobile 4 chipset
F16 -- 3.1.0-0.rc9.git0.0.fc16.x86_64

This laptop had F14, working perfectly. Upgraded to F15, and that's when the trouble started. GRUB loaded, but screen goes to black after. F15 still loading, but can't see anything. A search of this forum indicated that this bug was fixed in F16. Installed F16 beta. Same problem. (BTW, screen was black all thru preupgrade to F15 as well)

I have thus far tried:

acpi_osi=linux in kernel params, set xorg.conf to "intel"

...which resulted in same black screen. Checking logs after booting to CLI with "nomodeset single" showed X started normally.

Now then. I have gotten everything working right IF I do one of the following:

1 -- fiddle with the brightness controls (Fn + R/L) while the GRUB2 menu is up, before booting. Brightness keys then function normally.

2 -- If I don't do that, I get the black screen. If I wait for it to go to the login screen (blind), shut the lid to suspend, then resume, I get visible screen again -- but VERY dim. Got brightness back by editing value in /sys/class/backlight/intel_backlight/brightness. Brightness keys do not function this way.


Now, I might think this was a cool way to keep unauthorized people from using a laptop, but it's not my laptop, so it's an untenable situation! It's driving me nuts. Anyone have any ideas?

Method 1 above makes me think that the kernel doesn't know it's supposed to turn something on unless it catches a key input... before booting... ???


Added:

Method 2 -- on further suspend/resume cycles, screen comes back extremely dim. Editing the file sys/class/backlight/intel_backlight/brightness restores the normal brightness. It does not seem to matter what I set it to, either. I've tried various values, including 0. All bring back normal brightness as soon as I save the file.

[MikeCO]

Bump...

Almost 100 views on this... no one has any idea what's going on here?

[all your eyes]

I had a similar issue with an Acer Aspire 5732Z. I edited the kernel parameters in /boot/grub/grub.conf to include, "acpi_backlight=vendor acpi_osi=Linux" and every time the machine boots or is roused from a suspended state I have to push fn+left to have any backlight, and the brightness buttons are switched thereafter, with fn+left being brightness toggle up and fn+right toggle down.. Weird workaround, will have to be repeated with each kernel update, but it works. There has to be a way to fix this, it's been a bug for several years now.

[mese79]

Hi
I have a hp tm2(intel graphic) and i also have this issue with both F15 & F16.
It's really disappointing