[PATCH] drm/i915: VGA also requires the power well

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

So add a power domain and check for it before we try to read
VGA_CONTROL.

This fixes unclaimed register messages that happen on suspend/resume.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h      | 1 +
 drivers/gpu/drm/i915/intel_display.c | 3 +++
 drivers/gpu/drm/i915/intel_pm.c      | 1 +
 3 files changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 46b1f70..d51ce13 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -89,6 +89,7 @@ enum port {
 #define port_name(p) ((p) + 'A')
 
 enum intel_display_power_domain {
+	POWER_DOMAIN_VGA,
 	POWER_DOMAIN_PIPE_A,
 	POWER_DOMAIN_PIPE_B,
 	POWER_DOMAIN_PIPE_C,
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 4c8fcec..3719d99 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9950,6 +9950,9 @@ void i915_redisable_vga(struct drm_device *dev)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 vga_reg = i915_vgacntrl_reg(dev);
 
+	if (!intel_display_power_enabled(dev, POWER_DOMAIN_VGA))
+		return;
+
 	if (I915_READ(vga_reg) != VGA_DISP_DISABLE) {
 		DRM_DEBUG_KMS("Something enabled VGA plane, disabling it\n");
 		i915_disable_vga(dev);
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 50fe3d7..47ef4a6 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5000,6 +5000,7 @@ bool intel_display_power_enabled(struct drm_device *dev,
 	case POWER_DOMAIN_PIPE_A:
 	case POWER_DOMAIN_TRANSCODER_EDP:
 		return true;
+	case POWER_DOMAIN_VGA:
 	case POWER_DOMAIN_PIPE_B:
 	case POWER_DOMAIN_PIPE_C:
 	case POWER_DOMAIN_PIPE_A_PANEL_FITTER:
-- 
1.8.1.2