From: jsg <jsg@openbsd.org>
Date: Mon, 27 Mar 2023 04:29:05 +0000 (+0000)
Subject: drm/edid: fix AVI infoframe aspect ratio handling
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=b30923dda143be1363c5b3524ec96e45390dcd96;p=openbsd

drm/edid: fix AVI infoframe aspect ratio handling

From Jani Nikula
26cbe4c63d1ed6b7e47ca196fd59f8a32ed353ca in linux-6.1.y/6.1.16
1cbc1f0d324ba6c4d1b10ac6362b5e0b029f63d5 in mainline linux
---

diff --git a/sys/dev/pci/drm/drm_edid.c b/sys/dev/pci/drm/drm_edid.c
index 77c6e5ab31e..41799402212 100644
--- a/sys/dev/pci/drm/drm_edid.c
+++ b/sys/dev/pci/drm/drm_edid.c
@@ -6735,8 +6735,6 @@ static u8 drm_mode_hdmi_vic(const struct drm_connector *connector,
 static u8 drm_mode_cea_vic(const struct drm_connector *connector,
 			   const struct drm_display_mode *mode)
 {
-	u8 vic;
-
 	/*
 	 * HDMI spec says if a mode is found in HDMI 1.4b 4K modes
 	 * we should send its VIC in vendor infoframes, else send the
@@ -6746,13 +6744,18 @@ static u8 drm_mode_cea_vic(const struct drm_connector *connector,
 	if (drm_mode_hdmi_vic(connector, mode))
 		return 0;
 
-	vic = drm_match_cea_mode(mode);
+	return drm_match_cea_mode(mode);
+}
 
-	/*
-	 * HDMI 1.4 VIC range: 1 <= VIC <= 64 (CEA-861-D) but
-	 * HDMI 2.0 VIC range: 1 <= VIC <= 107 (CEA-861-F). So we
-	 * have to make sure we dont break HDMI 1.4 sinks.
-	 */
+/*
+ * Avoid sending VICs defined in HDMI 2.0 in AVI infoframes to sinks that
+ * conform to HDMI 1.4.
+ *
+ * HDMI 1.4 (CTA-861-D) VIC range: [1..64]
+ * HDMI 2.0 (CTA-861-F) VIC range: [1..107]
+ */
+static u8 vic_for_avi_infoframe(const struct drm_connector *connector, u8 vic)
+{
 	if (!is_hdmi2_sink(connector) && vic > 64)
 		return 0;
 
@@ -6828,7 +6831,7 @@ drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
 		picture_aspect = HDMI_PICTURE_ASPECT_NONE;
 	}
 
-	frame->video_code = vic;
+	frame->video_code = vic_for_avi_infoframe(connector, vic);
 	frame->picture_aspect = picture_aspect;
 	frame->active_aspect = HDMI_ACTIVE_ASPECT_PICTURE;
 	frame->scan_mode = HDMI_SCAN_MODE_UNDERSCAN;