Alex Villacís Lasso authored Jul 27, 2018 and Jonas Ådahl committed Aug 09, 2018

Commit c0d9b08e replaced the old GBM API calls
with the multi-plane GBM API. However, the call to gbm_bo_get_handle_for_plane
fails for some DRI drivers (in particular i915). Due to missing error checks,
the subsequent call to drmModeAddFB[2] fails and the screen output locks up.

This commit adds the missing error checks and falls back to the old GBM API
(non-planar) if necessary.

v5: test success of gbm_bo_get_handle_for_plane instead of errno

This commit adopts solution proposed by Daniel van Vugt to check the return
value of gbm_bo_get_handle_for_plane on plane 0 and fall back to old
non-planar method if the call fails. This removes the errno check (for
ENOSYS) that could abort if mesa ever sets a different value.

Related to: GNOME/mutter#127