ARM: edma: Add edma_assign_channel_eventq() to move channel to a give queue

In some cases it is desired to move a channel to a specific event queue.
Such a use case is audio, where it is preferred that it is served with
highest priority compared to other DMA clients.

Signed-off-by: Peter Ujfalusi <[e-mail]>
Acked-by: Sekhar Nori <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

arch/arm/common/edma.c

···
 }
 EXPORT_SYMBOL(edma_clear_event);
 
+/*
+ * edma_assign_channel_eventq - move given channel to desired eventq
+ * Arguments:
+ *	channel - channel number
+ *	eventq_no - queue to move the channel
+ *
+ * Can be used to move a channel to a selected event queue.
+ */
+void edma_assign_channel_eventq(unsigned channel, enum dma_event_q eventq_no)
+{
+	unsigned ctlr;
+
+	ctlr = EDMA_CTLR(channel);
+	channel = EDMA_CHAN_SLOT(channel);
+
+	if (channel >= edma_cc[ctlr]->num_channels)
+		return;
+
+	/* default to low priority queue */
+	if (eventq_no == EVENTQ_DEFAULT)
+		eventq_no = edma_cc[ctlr]->default_queue;
+	if (eventq_no >= edma_cc[ctlr]->num_tc)
+		return;
+
+	map_dmach_queue(ctlr, channel, eventq_no);
+}
+EXPORT_SYMBOL(edma_assign_channel_eventq);
+
 static int edma_setup_from_hw(struct device *dev, struct edma_soc_info *pdata,
 			      struct edma *edma_cc)
 {

include/linux/platform_data/edma.h

···
 void edma_pause(unsigned channel);
 void edma_resume(unsigned channel);
 
+void edma_assign_channel_eventq(unsigned channel, enum dma_event_q eventq_no);
+
 struct edma_rsv_info {
 
 	const s16	(*rsv_chans)[2];