diff options
author | Takashi Iwai <tiwai@suse.de> | 2012-08-11 08:56:42 +0200 |
---|---|---|
committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2012-08-11 21:15:16 +0200 |
commit | 770c12312ad617172b1a65b911d3e6564fc5aca8 (patch) | |
tree | 267bc8a7cd2c542654ac1ca1e4d217581b793517 /drivers/gpu | |
parent | 9830605d4c070b16ec5c24a75503877cc7698409 (diff) | |
download | lwn-770c12312ad617172b1a65b911d3e6564fc5aca8.tar.gz lwn-770c12312ad617172b1a65b911d3e6564fc5aca8.zip |
drm/i915: Fix blank panel at reopening lid
When you reopen the lid on a laptop with PCH, the panel suddenly goes
blank sometimes. It seems because BLC_PWM_CPU_CTL register is cleared
to zero when BLC_PWM_CPU_CTL2 and BLC_PWM_PCH_CTL1 registers are
enabled.
This patch fixes the problem by moving the call of the function setting
BLC_PWM_CPU_CTL after enabling other two registers.
Reported-and-tested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu')
-rw-r--r-- | drivers/gpu/drm/i915/intel_panel.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 9474488db948..3df4f5fa892a 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -311,9 +311,6 @@ void intel_panel_enable_backlight(struct drm_device *dev, if (dev_priv->backlight_level == 0) dev_priv->backlight_level = intel_panel_get_max_backlight(dev); - dev_priv->backlight_enabled = true; - intel_panel_actually_set_backlight(dev, dev_priv->backlight_level); - if (INTEL_INFO(dev)->gen >= 4) { uint32_t reg, tmp; @@ -326,7 +323,7 @@ void intel_panel_enable_backlight(struct drm_device *dev, * we don't track the backlight dpms state, hence check whether * we have to do anything first. */ if (tmp & BLM_PWM_ENABLE) - return; + goto set_level; if (dev_priv->num_pipe == 3) tmp &= ~BLM_PIPE_SELECT_IVB; @@ -347,6 +344,14 @@ void intel_panel_enable_backlight(struct drm_device *dev, I915_WRITE(BLC_PWM_PCH_CTL1, tmp); } } + +set_level: + /* Call below after setting BLC_PWM_CPU_CTL2 and BLC_PWM_PCH_CTL1. + * BLC_PWM_CPU_CTL may be cleared to zero automatically when these + * registers are set. + */ + dev_priv->backlight_enabled = true; + intel_panel_actually_set_backlight(dev, dev_priv->backlight_level); } static void intel_panel_init_backlight(struct drm_device *dev) |