[PATCH net] net/sonic: Use dma_mapping_error()

[Finn Thain]

With CONFIG_DMA_API_DEBUG=y, calling sonic_open() produces the
message, "DMA-API: device driver failed to check map error".
Add the missing dma_mapping_error() call.

Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/natsemi/sonic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c
index 7ed08486ae23..c805dcbebd02 100644
--- a/drivers/net/ethernet/natsemi/sonic.c
+++ b/drivers/net/ethernet/natsemi/sonic.c
@@ -84,7 +84,7 @@ static int sonic_open(struct net_device *dev)
 	for (i = 0; i < SONIC_NUM_RRS; i++) {
 		dma_addr_t laddr = dma_map_single(lp->device, skb_put(lp->rx_skb[i], SONIC_RBSIZE),
 		                                  SONIC_RBSIZE, DMA_FROM_DEVICE);
-		if (!laddr) {
+		if (dma_mapping_error(lp->device, laddr)) {
 			while(i > 0) { /* free any that were mapped successfully */
 				i--;
 				dma_unmap_single(lp->device, lp->rx_laddr[i], SONIC_RBSIZE, DMA_FROM_DEVICE);
-- 
2.16.1