[RFC PATCH 03/37] drm: mode: Allow NULL modes for equality check

[Daniel Stone]

Since we're now using mode == NULL to represent disabled, it's not
wholly surprising that we'd want to compare NULL modes.

Signed-off-by: Daniel Stone <daniels at collabora.com>
---
 drivers/gpu/drm/drm_modes.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 5388596..213b11e 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -903,6 +903,12 @@ EXPORT_SYMBOL(drm_mode_duplicate);
  */
 bool drm_mode_equal(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
 {
+	if (!mode1 && !mode2)
+		return true;
+
+	if (!mode1 || !mode2)
+		return false;
+
 	/* do clock check convert to PICOS so fb modes get matched
 	 * the same */
 	if (mode1->clock && mode2->clock) {
-- 
2.3.2