At Thu, 10 Nov 2011 16:11:29 +0100, Daniel Mack wrote:
On 11/08/2011 01:57 AM, Daniel Mack wrote:
Didn't get any response yet, hence copying LKML for a broader audience.
Nobody, really?
This is a rather annoying regression, as touching the brightness keys appearantly switches off the whole machine. I'm sure this is trivial to fix, I just don't have the insight of this driver and the chipset.
I vaguely remember that the bit 0 is invalid on some old chips. Maybe 915GM is one of them, as it's gen3? If so, the patch like below may work.
Takashi
--- diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 499d4c0..be952d1 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -249,8 +249,11 @@ static void intel_panel_actually_set_backlight(struct drm_device *dev, u32 level if (IS_PINEVIEW(dev)) { tmp &= ~(BACKLIGHT_DUTY_CYCLE_MASK - 1); level <<= 1; - } else + } else { tmp &= ~BACKLIGHT_DUTY_CYCLE_MASK; + if (INTEL_INFO(dev)->gen < 4) + tmp &= ~1; + } I915_WRITE(BLC_PWM_CTL, tmp | level); }