drm/amd/display: Add refresh rate range check

[ Upstream commit 74ad26b ]

[Why]
We only enable the VRR while monitor usable refresh rate range
is greater than 10 Hz.
But we did not check the range in DRM_EDID_FEATURE_CONTINUOUS_FREQ
case.

[How]
Add a refresh rate range check before set the freesync_capable flag
in DRM_EDID_FEATURE_CONTINUOUS_FREQ case.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Tom Chung

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -11289,9 +11289,11 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
 		if (is_dp_capable_without_timing_msa(adev->dm.dc,
 						     amdgpu_dm_connector)) {
 			if (edid->features & DRM_EDID_FEATURE_CONTINUOUS_FREQ) {
-				freesync_capable = true;
 				amdgpu_dm_connector->min_vfreq = connector->display_info.monitor_range.min_vfreq;
 				amdgpu_dm_connector->max_vfreq = connector->display_info.monitor_range.max_vfreq;
+				if (amdgpu_dm_connector->max_vfreq -
+				    amdgpu_dm_connector->min_vfreq > 10)
+					freesync_capable = true;
 			} else {
 				edid_check_required = edid->version > 1 ||
 						      (edid->version == 1 &&