mailbox: mtk-cmdq: Use mailbox rx_callback

rx_callback is a standard mailbox callback mechanism and could cover the
function of proprietary cmdq_task_cb, so use the standard one instead of
the proprietary one. But the client driver has already used cmdq_task_cb,
so keep cmdq_task_cb until all client driver use rx_callback instead of
cmdq_task_cb.

Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Reviewed-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Author: Chun-Kuang Hu

drivers/mailbox/mtk-cmdq-mailbox.c

@@ -188,7 +188,10 @@ static void cmdq_task_exec_done(struct cmdq_task *task, int sta)
 	WARN_ON(cb->cb == (cmdq_async_flush_cb)NULL);
 	data.sta = sta;
 	data.data = cb->data;
-	cb->cb(data);
+	if (cb->cb)
+		cb->cb(data);
+
+	mbox_chan_received_data(task->thread->chan, &data);
 
 	list_del(&task->list_entry);
 }
@@ -451,12 +454,13 @@ static int cmdq_mbox_flush(struct mbox_chan *chan, unsigned long timeout)
 
 	list_for_each_entry_safe(task, tmp, &thread->task_busy_list,
 				 list_entry) {
+		data.sta = -ECONNABORTED;
+		data.data = cb->data;
 		cb = &task->pkt->async_cb;
-		if (cb->cb) {
-			data.sta = -ECONNABORTED;
-			data.data = cb->data;
+		if (cb->cb)
 			cb->cb(data);
-		}
+
+		mbox_chan_received_data(task->thread->chan, &data);
 		list_del(&task->list_entry);
 		kfree(task);
 	}