From 7b2f0cdf9f7624ffd2878ddff9b9dc070a236462 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 11 Jan 2011 17:06:04 +0000 Subject: [PATCH] drm/i915/panel: Ensure that backlight enable/disabling is balanced By tracking the current status of the backlight we can prevent recording the value of the current backlight when we have disabled it. However, we need to be careful to preserve the value that the user may have independently set it to. By this we cannot rely on 0 == disable, but must check whether we expect the current value to be valid. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=22672 Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/intel_display.c | 2 ++ drivers/gpu/drm/i915/intel_drv.h | 3 +++ drivers/gpu/drm/i915/intel_lvds.c | 10 ++-------- drivers/gpu/drm/i915/intel_panel.c | 34 ++++++++++++++++++++++++++++++++++ 5 files changed, 42 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 409826d..d2896eb 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -329,6 +329,7 @@ typedef struct drm_i915_private { /* LVDS info */ int backlight_level; /* restore backlight to this value */ + bool backlight_enabled; struct drm_display_mode *panel_fixed_mode; struct drm_display_mode *lfp_lvds_vbt_mode; /* if any */ struct drm_display_mode *sdvo_lvds_vbt_mode; /* if any */ diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 142cb47..9dba616 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5933,6 +5933,8 @@ static void intel_setup_outputs(struct drm_device *dev) encoder->base.possible_clones = intel_encoder_clones(dev, encoder->clone_mask); } + + intel_panel_setup_backlight(dev); } static void intel_user_framebuffer_destroy(struct drm_framebuffer *fb) diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index e52c612..1e68293 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -256,6 +256,9 @@ extern void intel_pch_panel_fitting(struct drm_device *dev, extern u32 intel_panel_get_max_backlight(struct drm_device *dev); extern u32 intel_panel_get_backlight(struct drm_device *dev); extern void intel_panel_set_backlight(struct drm_device *dev, u32 level); +extern void intel_panel_setup_backlight(struct drm_device *dev); +extern void intel_panel_enable_backlight(struct drm_device *dev); +extern void intel_panel_disable_backlight(struct drm_device *dev); extern void intel_crtc_load_lut(struct drm_crtc *crtc); extern void intel_encoder_prepare (struct drm_encoder *encoder); diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c index 25bcedf..3538e6b 100644 --- a/drivers/gpu/drm/i915/intel_lvds.c +++ b/drivers/gpu/drm/i915/intel_lvds.c @@ -106,7 +106,7 @@ static void intel_lvds_enable(struct intel_lvds *intel_lvds) 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 @@ static void intel_lvds_disable(struct intel_lvds *intel_lvds) 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); @@ -395,8 +394,6 @@ static void intel_lvds_prepare(struct drm_encoder *encoder) 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. * @@ -427,9 +424,6 @@ static void intel_lvds_commit(struct drm_encoder *encoder) 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. */ diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c index 92ff8f3..c4b1ca4 100644 --- a/drivers/gpu/drm/i915/intel_panel.c +++ b/drivers/gpu/drm/i915/intel_panel.c @@ -218,3 +218,37 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level) tmp &= ~BACKLIGHT_DUTY_CYCLE_MASK; I915_WRITE(BLC_PWM_CTL, tmp | level); } + +void intel_panel_disable_backlight(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + + if (!dev_priv->backlight_enabled) + return; + + dev_priv->backlight_enabled = false; + dev_priv->backlight_level = intel_panel_get_backlight(dev); + intel_panel_set_backlight(dev, 0); +} + +void intel_panel_enable_backlight(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + + if (dev_priv->backlight_enabled) + return; + + if (dev_priv->backlight_level == 0) + dev_priv->backlight_level = intel_panel_get_max_backlight(dev); + + intel_panel_set_backlight(dev, dev_priv->backlight_level); + dev_priv->backlight_enabled = true; +} + +void intel_panel_setup_backlight(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + + dev_priv->backlight_level = intel_panel_get_max_backlight(dev); + dev_priv->backlight_enabled = dev_priv->backlight_level != 0; +} -- 1.7.2.3