diff options
| author | Takashi Iwai <tiwai@suse.de> | 2012-06-21 15:30:41 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-07-16 09:04:05 -0700 |
| commit | 6ad566e162cbf778300fd6bfe37c98b5ce46d58b (patch) | |
| tree | cb455e0dc0f4623a4cdb96805e9ffd999c1cbc6a /drivers/gpu/drm/i915 | |
| parent | eb858e23a8aa132d068aa639f617ba38e008d077 (diff) | |
drm/i915: Fix eDP blank screen after S3 resume on HP desktops
commit 6db65cbb941f9d433659bdad02b307f6d94465df upstream.
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
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/gpu/drm/i915')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_suspend.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c index 2b5eb229ff2..0d13778a5aa 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 + */ 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); |