This reverts commit 9efb16c2fdd647d3888fd8dae84509f485cd554e. Commit c1ec54b7b5af ("drm/mediatek: Use mailbox rx_callback instead of cmdq_task_cb") would cause numerous mtk cmdq mailbox driver warning: WARNING: CPU: 0 PID: 0 at drivers/mailbox/mtk-cmdq-mailbox.c:198 cmdq_task_exec_done+0xb8/0xe0 So revert that patch and all the patches depend on that patch. Reported-by: Enric Balletbo Serra <eballetbo@gmail.com> Tested-by: Enric Balletbo Serra <eballetbo@gmail.com> Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>