rcar-hpbdma: fixup channel busy check for double plane

The device busy check method is different between
single and double planes.
It will always return "busy" without this patch
if channel used as double plane.

Reviewed-by: Max Filippov <max.filippov@cogentembedded.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/sh/rcar-hpbdma.c b/drivers/dma/sh/rcar-hpbdma.c
index 496180a..83de1db 100644
--- a/drivers/dma/sh/rcar-hpbdma.c
+++ b/drivers/dma/sh/rcar-hpbdma.c
@@ -60,6 +60,7 @@
 #define HPB_DMAE_DSTPR_DMSTP	BIT(0)
 
 /* DMA status register (DSTSR) bits */
+#define HPB_DMAE_DSTSR_DQSTS	BIT(2)
 #define HPB_DMAE_DSTSR_DMSTS	BIT(0)
 
 /* DMA common registers */
@@ -385,7 +386,10 @@
 	struct hpb_dmae_chan *chan = to_chan(schan);
 	u32 dstsr = ch_reg_read(chan, HPB_DMAE_DSTSR);
 
-	return (dstsr & HPB_DMAE_DSTSR_DMSTS) == HPB_DMAE_DSTSR_DMSTS;
+	if (chan->xfer_mode == XFER_DOUBLE)
+		return dstsr & HPB_DMAE_DSTSR_DQSTS;
+	else
+		return dstsr & HPB_DMAE_DSTSR_DMSTS;
 }
 
 static int