Am Donnerstag, den 21.06.2012, 15:30 +0200 schrieb Takashi Iwai: > This patch fixes the problem on some HP desktop machines with eDP > which give blank screens after S3 resume. > > It turned out that BLC_PWM_CPU_CTL must be written after > BLC_PWM_CPU_CTL2. Otherwise it doesn't take effect on these > SNB machines. > > Tested with 3.5-rc3 kernel. > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49233 Hmm, the bug entry does not contain a link to the discussion on intel-gfx. http://lists.freedesktop.org/archives/intel-gfx/2012-June/018418.html Maybe add it there or to the commit message. > Cc: <stable at vger.kernel.org> > Signed-off-by: Takashi Iwai <tiwai at suse.de> > --- > drivers/gpu/drm/i915/i915_suspend.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c > index 0ede02a..a748e5c 100644 > --- a/drivers/gpu/drm/i915/i915_suspend.c > +++ b/drivers/gpu/drm/i915/i915_suspend.c > @@ -740,8 +740,11 @@ static void i915_restore_display(struct drm_device *dev) > if (HAS_PCH_SPLIT(dev)) { > I915_WRITE(BLC_PWM_PCH_CTL1, dev_priv->saveBLC_PWM_CTL); > I915_WRITE(BLC_PWM_PCH_CTL2, dev_priv->saveBLC_PWM_CTL2); > - I915_WRITE(BLC_PWM_CPU_CTL, dev_priv->saveBLC_CPU_PWM_CTL); > + /* NOTE: BLC_PWM_CPU_CTL must be written after BLC_PWM_CPU_CTL2; > + * otherwise we get blank eDP screen after S3 on some machines Full stop at the end? Also add a reference to the list discussion or Bugzilla entry? > + */ > I915_WRITE(BLC_PWM_CPU_CTL2, dev_priv->saveBLC_CPU_PWM_CTL2); > + I915_WRITE(BLC_PWM_CPU_CTL, dev_priv->saveBLC_CPU_PWM_CTL); > I915_WRITE(PCH_PP_ON_DELAYS, dev_priv->savePP_ON_DELAYS); > I915_WRITE(PCH_PP_OFF_DELAYS, dev_priv->savePP_OFF_DELAYS); > I915_WRITE(PCH_PP_DIVISOR, dev_priv->savePP_DIVISOR); With or without these changes above, this patch is Acked-by: Paul Menzel <paulepanter at users.sourceforge.net> Thanks, Paul -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 198 bytes Desc: This is a digitally signed message part URL: <http://lists.freedesktop.org/archives/intel-gfx/attachments/20120622/18858c6d/attachment.pgp>
