drm/i915/panel: Only record the backlight level when it is enabled
By tracking the current status of the backlight we can prevent recording
the value of the current backlight when we have disabled it. And so
prevent restoring it to 'off' after an unbalanced sequence of
intel_lvds_disable/enable.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=22672
Tested-by: Alex Riesen <raa.lkml@gmail.com>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index aa230708..4e7dcb3 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -106,7 +106,7 @@
I915_WRITE(ctl_reg, I915_READ(ctl_reg) | POWER_TARGET_ON);
POSTING_READ(lvds_reg);
- intel_panel_set_backlight(dev, dev_priv->backlight_level);
+ intel_panel_enable_backlight(dev);
}
static void intel_lvds_disable(struct intel_lvds *intel_lvds)
@@ -123,8 +123,7 @@
lvds_reg = LVDS;
}
- dev_priv->backlight_level = intel_panel_get_backlight(dev);
- intel_panel_set_backlight(dev, 0);
+ intel_panel_disable_backlight(dev);
I915_WRITE(ctl_reg, I915_READ(ctl_reg) & ~POWER_TARGET_ON);
@@ -398,8 +397,6 @@
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_lvds *intel_lvds = to_intel_lvds(encoder);
- dev_priv->backlight_level = intel_panel_get_backlight(dev);
-
/* We try to do the minimum that is necessary in order to unlock
* the registers for mode setting.
*
@@ -430,9 +427,6 @@
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_lvds *intel_lvds = to_intel_lvds(encoder);
- if (dev_priv->backlight_level == 0)
- dev_priv->backlight_level = intel_panel_get_max_backlight(dev);
-
/* Undo any unlocking done in prepare to prevent accidental
* adjustment of the registers.
*/