diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
index a7961c391de69e5b3eb9d90e0939fc714553b76f..7733dbd57073aa024dab541c94a4456432a3b69b 100644
--- a/drivers/mmc/host/bcm2835.c
+++ b/drivers/mmc/host/bcm2835.c
@@ -453,7 +453,7 @@ static void bcm2835_transfer_pio(struct bcm2835_host *host)
 static
 void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data)
 {
-	int len, dir_data, dir_slave;
+	int sg_len, dir_data, dir_slave;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *dma_chan;
 
@@ -499,15 +499,13 @@ void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data)
 				     &host->dma_cfg_rx :
 				     &host->dma_cfg_tx);
 
-	len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,
-			 dir_data);
+	sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,
+			    dir_data);
+	if (!sg_len)
+		return;
 
-	if (len > 0) {
-		desc = dmaengine_prep_slave_sg(dma_chan, data->sg,
-					       len, dir_slave,
-					       DMA_PREP_INTERRUPT |
-					       DMA_CTRL_ACK);
-	}
+	desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave,
+				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 
 	if (desc) {
 		desc->callback = bcm2835_dma_complete;