i915 completely unusable in 2.6.38.x
* Melchior FRANZ -- Tuesday 26 April 2011:
> [https://bugzilla.kernel.org/show_bug.cgi?id=31522]
I've replied to this error message, but here again for this audience:
The commit that broke all 2.6.38.* releases for my machine is this:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=ba3820ade317ee36e496b9b40d2ec3987dd4aef0
(Takashi Iwai: "drm/i915: Revive combination mode for backlight
control").
In 'is_backlight_combination_mode()' INTEL_INFO(dev)->gen
equals 4, and the function returns 0x4000 in "combination mode".
In 'intel_panel_get_backlight()' this happens:
val = I915_READ(BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK; // val = 0x0b4a
if (IS_PINEVIEW(dev)) // false
val >>= 1;
if (is_backlight_combination_mode(dev)){
u8 lbpc;
val &= ~1;// val = 0x0b4a
pci_read_config_byte(dev->pdev, PCI_LBPC, ); // lbpc = 0
val *= lbpc; // val = 0
}
The backlight remains off and does also not react to the "brighter" key
event.
Reverting the patch fixes my system, obviously.
m.
Re: i915 completely unusable in 2.6.38.x
* Melchior FRANZ -- Tuesday 26 April 2011:
[https://bugzilla.kernel.org/show_bug.cgi?id=31522]
I've replied to this error message, but here again for this audience:
The commit that broke all 2.6.38.* releases for my machine is this:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=ba3820ade317ee36e496b9b40d2ec3987dd4aef0
(Takashi Iwai: drm/i915: Revive combination mode for backlight
control).
In 'is_backlight_combination_mode()' INTEL_INFO(dev)-gen
equals 4, and the function returns 0x4000 in combination mode.
In 'intel_panel_get_backlight()' this happens:
val = I915_READ(BLC_PWM_CTL) BACKLIGHT_DUTY_CYCLE_MASK; // val = 0x0b4a
if (IS_PINEVIEW(dev)) // false
val = 1;
if (is_backlight_combination_mode(dev)){
u8 lbpc;
val = ~1;// val = 0x0b4a
pci_read_config_byte(dev-pdev, PCI_LBPC, lbpc); // lbpc = 0
val *= lbpc; // val = 0
}
The backlight remains off and does also not react to the brighter key
event.
Reverting the patch fixes my system, obviously.
m.
___
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel
