DMAENGINE: ste_dma40: don't pause/resume non-executing channels

There is no point in pausing what isn't running.
Signed-off-by: NJonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

drivers/dma/ste_dma40.c

@@ -768,6 +768,9 @@ static int d40_pause(struct dma_chan *chan)
 	int res = 0;
 	unsigned long flags;
 
+	if (!d40c->busy)
+		return 0;
+
 	spin_lock_irqsave(&d40c->lock, flags);
 
 	res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
@@ -792,6 +795,9 @@ static int d40_resume(struct dma_chan *chan)
 	int res = 0;
 	unsigned long flags;
 
+	if (!d40c->busy)
+		return 0;
+
 	spin_lock_irqsave(&d40c->lock, flags);
 
 	if (d40c->base->rev == 0)