drm/edid: compare actual vrefresh for all modes for quirks

The vrefresh field of the mode is 0 for most modes
fetched from the EDID (e.g., established timings).
When dealing with monitors that have a bogus preferred
mode, we may not always select the mode we want because
we compare the target refresh to the mode's vrefresh which
is 0 in a lot of cases.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 2f325bcd0708..fb7cf0e796f6 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1329,7 +1329,7 @@ static u32 edid_get_quirks(struct edid *edid)
 }
 
 #define MODE_SIZE(m) ((m)->hdisplay * (m)->vdisplay)
-#define MODE_REFRESH_DIFF(m,r) (abs((m)->vrefresh - target_refresh))
+#define MODE_REFRESH_DIFF(c,t) (abs((c) - (t)))
 
 /**
  * edid_fixup_preferred - set preferred modes based on quirk list
@@ -1344,6 +1344,7 @@ static void edid_fixup_preferred(struct drm_connector *connector,
 {
         struct drm_display_mode *t, *cur_mode, *preferred_mode;
         int target_refresh = 0;
+        int cur_vrefresh, preferred_vrefresh;
 
         if (list_empty(&connector->probed_modes))
                 return;
@@ -1366,10 +1367,14 @@ static void edid_fixup_preferred(struct drm_connector *connector,
                 if (MODE_SIZE(cur_mode) > MODE_SIZE(preferred_mode))
                         preferred_mode = cur_mode;
 
+                cur_vrefresh = cur_mode->vrefresh ?
+                        cur_mode->vrefresh : drm_mode_vrefresh(cur_mode);
+                preferred_vrefresh = preferred_mode->vrefresh ?
+                        preferred_mode->vrefresh : drm_mode_vrefresh(preferred_mode);
                 /* At a given size, try to get closest to target refresh */
                 if ((MODE_SIZE(cur_mode) == MODE_SIZE(preferred_mode)) &&
-                    MODE_REFRESH_DIFF(cur_mode, target_refresh) <
-                    MODE_REFRESH_DIFF(preferred_mode, target_refresh)) {
+                    MODE_REFRESH_DIFF(cur_vrefresh, target_refresh) <
+                    MODE_REFRESH_DIFF(preferred_vrefresh, target_refresh)) {
                         preferred_mode = cur_mode;
                 }
         }