drm/drm_blend: allow blend mode property without PREMULTI

Some hardware only supports the COVERAGE blend mode and lacks PREMULTI
support entirely. DRM currently requires that PREMULTI is present when
creating a blend mode property, which prevents such drivers from being
properly upstreamed.

Remove this restriction and allow drivers to create a blend mode
property without PREMULTI, enabling support for hardware that
implements only COVERAGE blend mode.

This does not introduce a regression, as no existing upstream drivers
expose only COVERAGE. However, userspace that wants to support such kind
of hardware in the future will have to check the supported blend modes
instead of assuming PREMULTI is always supported.

Signed-off-by: Leandro Ribeiro <leandro.ribeiro@collabora.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Link: https://patch.msgid.link/20260526181700.25310-2-leandro.ribeiro@collabora.com
Signed-off-by: Daniel Stone <daniels@collabora.com>

0 files changed, 0 insertions, 0 deletions