[PATCH v3 08/10] drm/i915/psr: Add intel_psr_is_psr_mode_changing

["Jouni Högander" <jouni.hogander@intel.com>]

Add new interface for checking possible PSR/PR mode change. We need this
information to decide if DSB can be used.

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
---
 drivers/gpu/drm/i915/display/intel_psr.c | 20 ++++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_psr.h |  2 ++
 2 files changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 1e99329b70a1..90e36e34e0c7 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -225,6 +225,26 @@ bool intel_psr_needs_aux_io_power(struct intel_encoder *encoder,
 	       intel_encoder_can_psr(encoder);
 }
 
+/**
+ * intel_psr_is_psr_mode_changing - Check if PSR/PR mode is changing
+ * @old_crtc_state: pointer to old intel_crtc_state
+ * @new_crtc_state: pointer to new intel_crtc_state
+ *
+ * This can be used to figure out if PSR/PR mode is changing between old and new
+ * crtc state.
+ *
+ * Returns true if mode is changing, false if mode is not changing.
+ */
+bool intel_psr_is_psr_mode_changing(const struct intel_crtc_state *old_crtc_state,
+				    const struct intel_crtc_state *new_crtc_state)
+{
+	return old_crtc_state->has_psr != new_crtc_state->has_psr ||
+		old_crtc_state->has_sel_update != new_crtc_state->has_sel_update ||
+		old_crtc_state->has_panel_replay != new_crtc_state->has_panel_replay ||
+		old_crtc_state->enable_psr2_su_region_et !=
+		new_crtc_state->enable_psr2_su_region_et;
+}
+
 static bool psr_global_enabled(struct intel_dp *intel_dp)
 {
 	struct intel_display *display = to_intel_display(intel_dp);
diff --git a/drivers/gpu/drm/i915/display/intel_psr.h b/drivers/gpu/drm/i915/display/intel_psr.h
index fc807817863e..cc6267e87933 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.h
+++ b/drivers/gpu/drm/i915/display/intel_psr.h
@@ -26,6 +26,8 @@ struct intel_plane_state;
 				    (intel_dp)->psr.source_panel_replay_support)
 
 bool intel_encoder_can_psr(struct intel_encoder *encoder);
+bool intel_psr_is_psr_mode_changing(const struct intel_crtc_state *old_crtc_state,
+				    const struct intel_crtc_state *new_crtc_state);
 bool intel_psr_needs_aux_io_power(struct intel_encoder *encoder,
 				  const struct intel_crtc_state *crtc_state);
 void intel_psr_init_dpcd(struct intel_dp *intel_dp);
-- 
2.43.0