drm/i915: use intel_crtc_control everywhere, v3.

Having a single path for everything makes it a lot easier to keep
crtc_state->active in sync with intel_crtc->active.

A crtc cannot be changed to active when not enabled, because it means
no mode is set and no connectors are connected.

This should also make intel_crtc->active match crtc_state->active.

Changes since v1:
- Reworded commit message, there's no intel_crtc_toggle.
Changes since v2:
- Change some callers of intel_crtc_control to intel_display_suspend.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 47d9854..aac252c 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -3630,12 +3630,18 @@
 	 */
 	if (crtc->config->cpu_transcoder == TRANSCODER_EDP &&
 	    !crtc->config->pch_pfit.enabled) {
+		bool active = crtc->active;
+
+		if (active)
+			intel_crtc_control(&crtc->base, false);
+
 		crtc->config->pch_pfit.force_thru = true;
 
 		intel_display_power_get(dev_priv,
 					POWER_DOMAIN_PIPE_PANEL_FITTER(PIPE_A));
 
-		intel_crtc_reset(crtc);
+		if (active)
+			intel_crtc_control(&crtc->base, true);
 	}
 	drm_modeset_unlock_all(dev);
 }
@@ -3654,12 +3660,18 @@
 	 * routing.
 	 */
 	if (crtc->config->pch_pfit.force_thru) {
-		crtc->config->pch_pfit.force_thru = false;
+		bool active = crtc->active;
 
-		intel_crtc_reset(crtc);
+		if (active)
+			intel_crtc_control(&crtc->base, false);
+
+		crtc->config->pch_pfit.force_thru = false;
 
 		intel_display_power_put(dev_priv,
 					POWER_DOMAIN_PIPE_PANEL_FITTER(PIPE_A));
+
+		if (active)
+			intel_crtc_control(&crtc->base, true);
 	}
 	drm_modeset_unlock_all(dev);
 }