The function can only be called from a s_stream handler as it requires a valid display list context (due to calling vsp1_uds_set_alpha() which writes to module registers). Document the requirement. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx> --- drivers/media/platform/vsp1/vsp1_pipe.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/media/platform/vsp1/vsp1_pipe.c b/drivers/media/platform/vsp1/vsp1_pipe.c index cb67b8f80635..a9a754e17e8d 100644 --- a/drivers/media/platform/vsp1/vsp1_pipe.c +++ b/drivers/media/platform/vsp1/vsp1_pipe.c @@ -318,6 +318,9 @@ done: * to be scaled, we disable alpha scaling when the UDS input has a fixed alpha * value. The UDS then outputs a fixed alpha value which needs to be programmed * from the input RPF alpha. + * + * This function can only be called from a subdev s_stream handler as it + * requires a valid display list context. */ void vsp1_pipeline_propagate_alpha(struct vsp1_pipeline *pipe, struct vsp1_entity *input, -- 2.7.3
