diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_display.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 3bc6ab5..841f039 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -1516,8 +1516,10 @@ static void intel_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe, reg = PIPECONF(pipe); val = I915_READ(reg); - val |= PIPECONF_ENABLE; - I915_WRITE(reg, val); + if (val & PIPECONF_ENABLE) + return; + + I915_WRITE(reg, val | PIPECONF_ENABLE); intel_wait_for_vblank(dev_priv->dev, pipe); } @@ -1551,8 +1553,10 @@ static void intel_disable_pipe(struct drm_i915_private *dev_priv, reg = PIPECONF(pipe); val = I915_READ(reg); - val &= ~PIPECONF_ENABLE; - I915_WRITE(reg, val); + if ((val & PIPECONF_ENABLE) == 0) + return; + + I915_WRITE(reg, val & ~PIPECONF_ENABLE); intel_wait_for_pipe_off(dev_priv->dev, pipe); } @@ -1575,8 +1579,10 @@ static void intel_enable_plane(struct drm_i915_private *dev_priv, reg = DSPCNTR(plane); val = I915_READ(reg); - val |= DISPLAY_PLANE_ENABLE; - I915_WRITE(reg, val); + if (val & DISPLAY_PLANE_ENABLE) + return; + + I915_WRITE(reg, val | DISPLAY_PLANE_ENABLE); intel_wait_for_vblank(dev_priv->dev, pipe); } @@ -1607,8 +1613,10 @@ static void intel_disable_plane(struct drm_i915_private *dev_priv, reg = DSPCNTR(plane); val = I915_READ(reg); - val &= ~DISPLAY_PLANE_ENABLE; - I915_WRITE(reg, val); + if ((val & DISPLAY_PLANE_ENABLE) == 0) + return; + + I915_WRITE(reg, val & ~DISPLAY_PLANE_ENABLE); intel_flush_display_plane(dev_priv, plane); intel_wait_for_vblank(dev_priv->dev, pipe); } |