[PATCH v2 04/19] drm/amd/display: Use bigger VRR range if found in AMD vsdb

["Tomasz Pakuła" <tomasz.pakula.oficjalny@gmail.com>]

[Why]
Some monitors only expose their full VRR range in AMD vsdb for some
reason.

[How]
Compare exposed ranges and use the bigger one.

This check could be merged with the previous one but it's better to keep
them separate to easily convey their meaning.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4177
Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c    | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index e4f4d6ba09c3..68a59275dead 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -13221,6 +13221,18 @@ static bool copy_range_to_amdgpu_connector(struct drm_connector *conn)
 	return is_freesync_capable(range);
 }
 
+/*
+ * Returns true if range from AMD vsdb is bigger
+ */
+static bool compare_ranges(struct drm_connector *conn,
+			   struct amdgpu_hdmi_vsdb_info *vsdb)
+{
+	struct drm_monitor_range_info *range = &conn->display_info.monitor_range;
+
+	return (vsdb->max_refresh_rate_hz - vsdb->min_refresh_rate_hz) >
+	       (range->max_vfreq - range->min_vfreq);
+}
+
 /**
  * amdgpu_dm_update_freesync_caps - Update Freesync capabilities
  *
@@ -13294,6 +13306,10 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
 		if (valid_vsdb_cea && is_monitor_range_invalid(connector))
 			monitor_range_from_vsdb(connector, &vsdb_info);
 
+		/* Use bigger range if found in AMD vsdb */
+		if (valid_vsdb_cea && compare_ranges(connector, &vsdb_info))
+			monitor_range_from_vsdb(connector, &vsdb_info);
+
 		if (dpcd_caps.allow_invalid_MSA_timing_param)
 			freesync_capable = copy_range_to_amdgpu_connector(connector);
 
-- 
2.52.0