[Intel-gfx] [PATCH 02/11] drm/edid: Clarify why we only accept the "range limits only" descriptor

Ville Syrjala
2022-08-26T21:35:42Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

The current comment fails to clarify why we only accept
the "range limits only" variant of the range descriptor.
Reword it to make some actual sense.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: amd-gfx@lists.freedesktop.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/drm_edid.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 4005dab6147d..ac662495635c 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -6033,10 +6033,13 @@ void get_monitor_range(const struct detailed_timing *timing, void *c)
return;

/*
- * Check for flag range limits only. If flag == 1 then
- * no additional timing information provided.
- * Default GTF, GTF Secondary curve and CVT are not
- * supported
+ * These limits are used to determine the VRR refresh
+ * rate range. Only the "range limits only" variant
+ * of the range descriptor seems to guarantee that
+ * any and all timings are accepted by the sink, as
+ * opposed to just timings conforming to the indicated
+ * formula (GTF/GTF2/CVT). Thus other variants of the
+ * range descriptor are not accepted here.
*/
if (range->flags != DRM_EDID_RANGE_LIMITS_ONLY_FLAG)
return;
--
2.35.1