Re: [3.0-rc1] i915: blank screen on Lenovo Ideapad U160

["Robert P. J. Day" <rpjday@crashcourse.ca>]

On Tue, 31 May 2011, Dirk Gouders wrote:

> Hello,
>
> I tested 3.0.0-rc1 on my notebook which has never been the best friend
> of the i915 driver.  With linux-2.6.38-gentoo-r4 it has the problem
> that the screen remains blank after the lid is closed and reopened, but
> that problem I can live with.  With 3.0.0-r1 I am back to a former
> problem that the screen goes (and remains) blank while booting.
>
> The next step I will do is to test linux-2.6.39-gentoo, probably I
> did not notice information that I have to adjust boot parameters or the
> kernel config?

  based on my having lived through the i915 "black screen of death",
pulling out my handy "git bisect" and with advice from chris wilson,
these days, i simply apply this patch to the source:

diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index d2c7104..a1a5d03 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -152,6 +152,8 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 	struct opregion_asle *asle = dev_priv->opregion.asle;
 	u32 max;

+return ASLE_BACKLIGHT_FAILED; // rday
+
 	if (!(bclp & ASLE_BCLP_VALID))
 		return ASLE_BACKLIGHT_FAILED;


  i tried taking it out a couple of times and immediately got the same
i915-related problem so until i hear differently, the patch stays in.

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
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