In __drm_atomic_helper_plane_state_init(), pixel_blend_mode is always
reset to DRM_MODE_BLEND_PREMULTI. That was consistent while
drm_plane_create_blend_mode_property() required PREMULTI in the
supported modes, but it now falls back to COVERAGE or PIXEL_NONE when
the driver doesn't support PREMULTI. The hardcoded default may therefore
not be a blend mode the hardware can do, nor one the property
advertises.
Initialize pixel_blend_mode from the blend mode property default
instead, keeping DRM_MODE_BLEND_PREMULTI for planes without the
property.
Fixes: 9813e158d1 ("drm/drm_blend: allow blend mode property without PREMULTI")
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Alex Hung <alex.hung@amd.com>
Reviewed-by: Leandro Ribeiro <leandro.ribeiro@collabora.com>
Signed-off-by: Melissa Wen <mwen@igalia.com>
Link: https://patch.msgid.link/20260826104143.39077-2-mwen@igalia.com