Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / i915 / i915_suspend.c

diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c
index 0ede02a99d914544d145b043b1ea066b5254bb02..a748e5cabe14e1e3ca4550db29078e0c45464682 100644 (file)
--- 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);