drm/i915: Make intel_display_suspend atomic, v2.

Calculate all state using a normal transition, but afterwards fudge
crtc->state->active back to its old value. This should still allow
state restore in setup_hw_state to work properly.

Calling intel_set_mode will cause intel_display_set_init_power to be
called, make sure init_power gets set again afterwards.

Changes since v1:
- Fix to compile with v2 of the patch that adds intel_display_suspend.
- Add intel_display_set_init_power.
- Set return value to int to allow error checking.

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/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 048a868..547d6db 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6214,27 +6214,58 @@
  * turn all crtc's off, but do not adjust state
  * This has to be paired with a call to intel_modeset_setup_hw_state.
  */
-void intel_display_suspend(struct drm_device *dev)
+int intel_display_suspend(struct drm_device *dev)
 {
-	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct drm_mode_config *config = &dev->mode_config;
+	struct drm_modeset_acquire_ctx *ctx = config->acquire_ctx;
+	struct drm_atomic_state *state;
 	struct drm_crtc *crtc;
+	unsigned crtc_mask = 0;
+	int ret = 0;
+
+	if (WARN_ON(!ctx))
+		return 0;
+
+	lockdep_assert_held(&ctx->ww_ctx);
+	state = drm_atomic_state_alloc(dev);
+	if (WARN_ON(!state))
+		return -ENOMEM;
+
+	state->acquire_ctx = ctx;
+	state->allow_modeset = true;
 
 	for_each_crtc(dev, crtc) {
-		struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-		enum intel_display_power_domain domain;
-		unsigned long domains;
+		struct drm_crtc_state *crtc_state =
+			drm_atomic_get_crtc_state(state, crtc);
 
-		if (!intel_crtc->active)
+		ret = PTR_ERR_OR_ZERO(crtc_state);
+		if (ret)
+			goto free;
+
+		if (!crtc_state->active)
 			continue;
 
-		intel_crtc_disable_planes(crtc);
-		dev_priv->display.crtc_disable(crtc);
-
-		domains = intel_crtc->enabled_power_domains;
-		for_each_power_domain(domain, domains)
-			intel_display_power_put(dev_priv, domain);
-		intel_crtc->enabled_power_domains = 0;
+		crtc_state->active = false;
+		crtc_mask |= 1 << drm_crtc_index(crtc);
 	}
+
+	if (crtc_mask) {
+		ret = intel_set_mode(state);
+
+		if (!ret) {
+			for_each_crtc(dev, crtc)
+				if (crtc_mask & (1 << drm_crtc_index(crtc)))
+					crtc->state->active = true;
+
+			return ret;
+		}
+	}
+
+free:
+	if (ret)
+		DRM_ERROR("Suspending crtc's failed with %i\n", ret);
+	drm_atomic_state_free(state);
+	return ret;
 }
 
 /* Master function to enable/disable CRTC and corresponding power wells */