drm/i915: Pass the current pipe from eDP init to backlight setup

On VLV/CHV both pipes A and B have their own backlight control
registers. In order to correctly read out the current hardware state at
init we need to know which pipe is driving the eDP port. Pass that
information down from the eDP init code into the backlight code.

To determine the correct pipe we first look at which pipe is currently
configured in the port control register, if that look invalid we look
at which pipe's PPS is currently controlling the port, and if that
too looks invalid we just assume pipe A.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 17 insertions, 14 deletions

diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 4ec6c2feef42..69bbfbaa4680 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -1117,7 +1117,7 @@ static u32 get_backlight_min_vbt(struct intel_connector *connector)
 		     0, panel->backlight.max);
 }
 
-static int bdw_setup_backlight(struct intel_connector *connector)
+static int bdw_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
 	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1143,7 +1143,7 @@ static int bdw_setup_backlight(struct intel_connector *connector)
 	return 0;
 }
 
-static int pch_setup_backlight(struct intel_connector *connector)
+static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
 	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1170,7 +1170,7 @@ static int pch_setup_backlight(struct intel_connector *connector)
 	return 0;
 }
 
-static int i9xx_setup_backlight(struct intel_connector *connector)
+static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
 	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1202,7 +1202,7 @@ static int i9xx_setup_backlight(struct intel_connector *connector)
 	return 0;
 }
 
-static int i965_setup_backlight(struct intel_connector *connector)
+static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
 {
 	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1232,37 +1232,40 @@ static int i965_setup_backlight(struct intel_connector *connector)
 	return 0;
 }
 
-static int vlv_setup_backlight(struct intel_connector *connector)
+static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
 {
 	struct drm_device *dev = connector->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_panel *panel = &connector->panel;
-	enum pipe pipe;
+	enum pipe p;
 	u32 ctl, ctl2, val;
 
-	for_each_pipe(dev_priv, pipe) {
-		u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(pipe));
+	for_each_pipe(dev_priv, p) {
+		u32 cur_val = I915_READ(VLV_BLC_PWM_CTL(p));
 
 		/* Skip if the modulation freq is already set */
 		if (cur_val & ~BACKLIGHT_DUTY_CYCLE_MASK)
 			continue;
 
 		cur_val &= BACKLIGHT_DUTY_CYCLE_MASK;
-		I915_WRITE(VLV_BLC_PWM_CTL(pipe), (0xf42 << 16) |
+		I915_WRITE(VLV_BLC_PWM_CTL(p), (0xf42 << 16) |
 			   cur_val);
 	}
 
-	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(PIPE_A));
+	if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
+		return -ENODEV;
+
+	ctl2 = I915_READ(VLV_BLC_PWM_CTL2(pipe));
 	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
 
-	ctl = I915_READ(VLV_BLC_PWM_CTL(PIPE_A));
+	ctl = I915_READ(VLV_BLC_PWM_CTL(pipe));
 	panel->backlight.max = ctl >> 16;
 	if (!panel->backlight.max)
 		return -ENODEV;
 
 	panel->backlight.min = get_backlight_min_vbt(connector);
 
-	val = _vlv_get_backlight(dev, PIPE_A);
+	val = _vlv_get_backlight(dev, pipe);
 	panel->backlight.level = intel_panel_compute_brightness(connector, val);
 
 	panel->backlight.enabled = (ctl2 & BLM_PWM_ENABLE) &&
@@ -1271,7 +1274,7 @@ static int vlv_setup_backlight(struct intel_connector *connector)
 	return 0;
 }
 
-int intel_panel_setup_backlight(struct drm_connector *connector)
+int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1290,7 +1293,7 @@ int intel_panel_setup_backlight(struct drm_connector *connector)
 
 	/* set level and max in panel struct */
 	mutex_lock(&dev_priv->backlight_lock);
-	ret = dev_priv->display.setup_backlight(intel_connector);
+	ret = dev_priv->display.setup_backlight(intel_connector, pipe);
 	mutex_unlock(&dev_priv->backlight_lock);
 
 	if (ret) {