drm/i915: Shuffle modeset reset handling around

Currently we're doing the reset handling a bit late, and we're doing
it both in the driver load code and on resume. This makes it unusable
for e.g. resetting the panel power sequence state like Paulo wants to.

Instead of adding yet another single-use callback shuffle things
around:
- Output handling code is responsible to reset/init all state on its
  own at driver load time.
- We call the reset functions much earlier, before we start using any
  of the modeset code.

Compared to Paulo's new ->resume callback the only difference in
placement is that ->reset is still called without dev->struct_mutex
held. Which is imo a feature.

v2: Rebase on top of the now merge dinq.

Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.c

@@ -643,6 +643,7 @@ static int __i915_drm_thaw(struct drm_device *dev, bool restore_gtt_mappings)
 	/* KMS EnterVT equivalent */
 	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
 		intel_init_pch_refclk(dev);
+		drm_mode_config_reset(dev);
 
 		mutex_lock(&dev->struct_mutex);
 
@@ -655,7 +656,6 @@ static int __i915_drm_thaw(struct drm_device *dev, bool restore_gtt_mappings)
 		intel_modeset_init_hw(dev);
 
 		drm_modeset_lock_all(dev);
-		drm_mode_config_reset(dev);
 		intel_modeset_setup_hw_state(dev, true);
 		drm_modeset_unlock_all(dev);
 

drivers/gpu/drm/i915/intel_crt.c

@@ -857,4 +857,6 @@ void intel_crt_init(struct drm_device *dev)
 
 		dev_priv->fdi_rx_config = I915_READ(_FDI_RXA_CTL) & fdi_config;
 	}
+
+	intel_crt_reset(connector);
 }

drivers/gpu/drm/i915/intel_display.c

@@ -11441,7 +11441,6 @@ void intel_modeset_gem_init(struct drm_device *dev)
 	intel_setup_overlay(dev);
 
 	mutex_lock(&dev->mode_config.mutex);
-	drm_mode_config_reset(dev);
 	intel_modeset_setup_hw_state(dev, false);
 	mutex_unlock(&dev->mode_config.mutex);
 }