drm/vc4: hdmi: Replace drm_detect_hdmi_monitor() with is_hdmi

Once EDID is parsed, the monitor HDMI support information is cached in
drm_display_info.is_hdmi by drm_parse_hdmi_vsdb_video().

This driver calls drm_detect_hdmi_monitor() to receive the same
information and stores its own cached value in
vc4_hdmi_encoder.hdmi_monitor, which is less efficient.

Avoid calling drm_detect_hdmi_monitor() and use drm_display_info.is_hdmi
instead. This also allows to remove vc4_hdmi_encoder.hdmi_monitor.

drm_detect_hdmi_monitor() is called in vc4_hdmi_connector_detect() and
vc4_hdmi_connector_get_modes(). In both cases it is safe to rely on
drm_display_info.is_hdmi as shown by ftrace:

$ sudo trace-cmd record -p function_graph -l "vc4_hdmi_*" -l "drm_*"

vc4_hdmi_connector_detect:

    vc4_hdmi_connector_detect() {
      drm_get_edid() {
        drm_connector_update_edid_property() {
          drm_add_display_info() {
            drm_reset_display_info();
            drm_for_each_detailed_block.part.0();
            drm_parse_cea_ext() {
              drm_find_cea_extension();
              drm_parse_hdmi_vsdb_video();
              /* drm_display_info.is_hdmi is cached here */
            }
          }
        }
      }
      /* drm_display_info.is_hdmi is used here */
    }

vc4_hdmi_connector_get_modes:

    vc4_hdmi_connector_get_modes() {
      drm_get_edid() {
        drm_connector_update_edid_property() {
          drm_add_display_info() {
            drm_reset_display_info();
            drm_for_each_detailed_block.part.0();
            drm_parse_cea_ext() {
              drm_find_cea_extension();
              drm_parse_hdmi_vsdb_video();
              /* drm_display_info.is_hdmi is cached here */
            }
          }
        }
      }
      /* drm_display_info.is_hdmi is used here */
      drm_connector_update_edid_property();
    }
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220420114500.187664-2-jose.exposito89@gmail.com

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -130,9 +130,9 @@ static bool vc4_hdmi_mode_needs_scrambling(const struct drm_display_mode *mode,
 static bool vc4_hdmi_is_full_range_rgb(struct vc4_hdmi *vc4_hdmi,
 				       const struct drm_display_mode *mode)
 {
-	struct vc4_hdmi_encoder *vc4_encoder = &vc4_hdmi->encoder;
+	struct drm_display_info *display = &vc4_hdmi->connector.display_info;
 
-	return !vc4_encoder->hdmi_monitor ||
+	return !display->is_hdmi ||
 		drm_default_rgb_quant_range(mode) == HDMI_QUANTIZATION_RANGE_FULL;
 }
 
@@ -239,7 +239,6 @@ vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
 
 			if (edid) {
 				cec_s_phys_addr_from_edid(vc4_hdmi->cec_adap, edid);
-				vc4_hdmi->encoder.hdmi_monitor = drm_detect_hdmi_monitor(edid);
 				kfree(edid);
 			}
 		}
@@ -265,7 +264,6 @@ static void vc4_hdmi_connector_destroy(struct drm_connector *connector)
 static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
 {
 	struct vc4_hdmi *vc4_hdmi = connector_to_vc4_hdmi(connector);
-	struct vc4_hdmi_encoder *vc4_encoder = &vc4_hdmi->encoder;
 	int ret = 0;
 	struct edid *edid;
 
@@ -278,8 +276,6 @@ static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
 		goto out;
 	}
 
-	vc4_encoder->hdmi_monitor = drm_detect_hdmi_monitor(edid);
-
 	drm_connector_update_edid_property(connector, edid);
 	ret = drm_add_edid_modes(connector, edid);
 	kfree(edid);
@@ -632,13 +628,12 @@ static void vc4_hdmi_set_infoframes(struct drm_encoder *encoder)
 static bool vc4_hdmi_supports_scrambling(struct drm_encoder *encoder,
 					 struct drm_display_mode *mode)
 {
-	struct vc4_hdmi_encoder *vc4_encoder = to_vc4_hdmi_encoder(encoder);
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	struct drm_display_info *display = &vc4_hdmi->connector.display_info;
 
 	lockdep_assert_held(&vc4_hdmi->mutex);
 
-	if (!vc4_encoder->hdmi_monitor)
+	if (!display->is_hdmi)
 		return false;
 
 	if (!display->hdmi.scdc.supported ||
@@ -1281,7 +1276,7 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder,
 {
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
-	struct vc4_hdmi_encoder *vc4_encoder = to_vc4_hdmi_encoder(encoder);
+	struct drm_display_info *display = &vc4_hdmi->connector.display_info;
 	bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
 	bool vsync_pos = mode->flags & DRM_MODE_FLAG_PVSYNC;
 	unsigned long flags;
@@ -1302,7 +1297,7 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder,
 	HDMI_WRITE(HDMI_VID_CTL,
 		   HDMI_READ(HDMI_VID_CTL) & ~VC4_HD_VID_CTL_BLANKPIX);
 
-	if (vc4_encoder->hdmi_monitor) {
+	if (display->is_hdmi) {
 		HDMI_WRITE(HDMI_SCHEDULER_CONTROL,
 			   HDMI_READ(HDMI_SCHEDULER_CONTROL) |
 			   VC4_HDMI_SCHEDULER_CONTROL_MODE_HDMI);
@@ -1329,7 +1324,7 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder,
 			  "!VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE\n");
 	}
 
-	if (vc4_encoder->hdmi_monitor) {
+	if (display->is_hdmi) {
 		spin_lock_irqsave(&vc4_hdmi->hw_lock, flags);
 
 		WARN_ON(!(HDMI_READ(HDMI_SCHEDULER_CONTROL) &

drivers/gpu/drm/vc4/vc4_hdmi.h

@@ -11,7 +11,6 @@
 /* VC4 HDMI encoder KMS struct */
 struct vc4_hdmi_encoder {
 	struct vc4_encoder base;
-	bool hdmi_monitor;
 };
 
 static inline struct vc4_hdmi_encoder *