On 31.05.2022 12:13, William Tseng wrote:
This is a workaround for HDMI 1.4 sink which has a CEA mode with higher vic
than what is defined in CEA-861-D.
As an example, a HDMI 1.4 sink has the video format 2560x1080p to be
displayed and the video format is indicated by both SVD (with vic 90 and
pictuure aspect ratio 64:27) and DTD. When connecting to such sink,
source can't output the video format in SVD because an error is returned by
drm_hdmi_avi_infoframe_from_display_mode(), which can't fill the infoframe
with pictuure aspect ratio 64:27 and the vic, which is originally 90 and is
changed to 0 by drm_mode_cea_vic().
To work around it, this patch ignores such CEA modes in do_cea_modes() so
the modes won't be processed in drm_hdmi_avi_infoframe_from_display_mode().
And only the video format in DTD can be dispalyed.
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Wayne Lin <waynelin@xxxxxxx>
Cc: Lee Shawn C <shawn.c.lee@xxxxxxxxx>
Signed-off-by: William Tseng <william.tseng@xxxxxxxxx>
---
drivers/gpu/drm/drm_edid.c | 39 +++++++++++++++++++++++++-------------
1 file changed, 26 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index bc43e1b32092..a93f68878bfd 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -3982,6 +3982,19 @@ drm_display_mode_from_cea_vic(struct drm_device *dev,
}
EXPORT_SYMBOL(drm_display_mode_from_cea_vic);
+static bool is_hdmi2_sink(const struct drm_connector *connector)
+{
+ /*
+ * FIXME: sil-sii8620 doesn't have a connector around when
+ * we need one, so we have to be prepared for a NULL connector.
+ */
+ if (!connector)
+ return true;
+
+ return connector->display_info.hdmi.scdc.supported ||
+ connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR420;
+}
+
static int
do_cea_modes(struct drm_connector *connector, const u8 *db, u8 len)
{
@@ -3993,6 +4006,19 @@ do_cea_modes(struct drm_connector *connector, const u8 *db, u8 len)
mode = drm_display_mode_from_vic_index(connector, db, len, i);
if (mode) {
+ u8 vic = svd_to_vic(db[i]);
+
+ if (!drm_valid_cea_vic(vic))
+ continue;
It duplicates check from drm_display_mode_from_vic_index
+
+ /*
+ * 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.
+ */
+ if (!is_hdmi2_sink(connector) && vic > 64)
+ continue;
So maybe adding this check to drm_display_mode_from_vic_index would be
enough?
Regards
Andrzej
+
/*
* YCBCR420 capability block contains a bitmap which
* gives the index of CEA modes from CEA VDB, which
@@ -5846,19 +5872,6 @@ void drm_set_preferred_mode(struct drm_connector *connector,
}
EXPORT_SYMBOL(drm_set_preferred_mode);
-static bool is_hdmi2_sink(const struct drm_connector *connector)
-{
- /*
- * FIXME: sil-sii8620 doesn't have a connector around when
- * we need one, so we have to be prepared for a NULL connector.
- */
- if (!connector)
- return true;
-
- return connector->display_info.hdmi.scdc.supported ||
- connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR420;
-}
-
static u8 drm_mode_hdmi_vic(const struct drm_connector *connector,
const struct drm_display_mode *mode)
{
