Matching modes for mirroring should preserve interlacing.

Add a condition when searching for modes for mirroring -
both modes must either be interlaced or progressive scan.

Also, as internal panels don't support interlacing,
do not attempt to panel fit interlaced modes on them.

BUG=179207
TEST=Manually disabled modes, making interlaced one the preferred,
     then verified that this mode is not picked for mirroring,
     but the next one. Steps in the bug should also work,
     but I don't have the necessary hardware.

Review URL: https://chromiumcodereview.appspot.com/12388090

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@186231 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 7 insertions, 2 deletions

diff --git a/chromeos/display/output_configurator.cc b/chromeos/display/output_configurator.cc
index 4357b1a..c460114 100644
--- a/chromeos/display/output_configurator.cc
+++ b/chromeos/display/output_configurator.cc
@@ -1070,8 +1070,11 @@ bool OutputConfigurator::FindOrCreateMirrorMode(Display* display,
     for (int j = 0; j < internal_info->nmode; j++) {
       internal_mode_id = internal_info->modes[j];
       XRRModeInfo* internal_mode = ModeInfoForID(screen, internal_mode_id);
+      bool is_internal_interlaced = internal_mode->modeFlags & RR_Interlace;
+      bool is_external_interlaced = external_mode->modeFlags & RR_Interlace;
       if (internal_mode->width == external_mode->width &&
-          internal_mode->height == external_mode->height) {
+          internal_mode->height == external_mode->height &&
+          is_internal_interlaced == is_external_interlaced) {
         *internal_mirror_mode = internal_mode_id;
         *external_mirror_mode = external_mode_id;
         return true;  // Mirror mode found
@@ -1082,9 +1085,11 @@ bool OutputConfigurator::FindOrCreateMirrorMode(Display* display,
     if (try_creating) {
       // We can downscale by 1.125, and upscale indefinitely
       // Downscaling looks ugly, so, can fit == can upscale
+      // Also, internal panels don't support fitting interlaced modes
       bool can_fit =
           internal_native_mode->width >= external_mode->width &&
-          internal_native_mode->height >= external_mode->height;
+          internal_native_mode->height >= external_mode->height &&
+          !(external_mode->modeFlags & RR_Interlace);
       if (can_fit) {
         XRRAddOutputMode(display, internal_output_id, external_mode_id);
         *internal_mirror_mode = *external_mirror_mode = external_mode_id;