ethoc: Use resource_size

Use the resource_size function instead of manually calculating the
resource size.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethoc.c b/drivers/net/ethoc.c
index bd1db92..f9d5ca0 100644
--- a/drivers/net/ethoc.c
+++ b/drivers/net/ethoc.c
@@ -904,7 +904,7 @@
 	}
 
 	mmio = devm_request_mem_region(&pdev->dev, res->start,
-			res->end - res->start + 1, res->name);
+			resource_size(res), res->name);
 	if (!mmio) {
 		dev_err(&pdev->dev, "cannot request I/O memory space\n");
 		ret = -ENXIO;
@@ -917,7 +917,7 @@
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	if (res) {
 		mem = devm_request_mem_region(&pdev->dev, res->start,
-			res->end - res->start + 1, res->name);
+			resource_size(res), res->name);
 		if (!mem) {
 			dev_err(&pdev->dev, "cannot request memory space\n");
 			ret = -ENXIO;
@@ -945,7 +945,7 @@
 	priv->dma_alloc = 0;
 
 	priv->iobase = devm_ioremap_nocache(&pdev->dev, netdev->base_addr,
-			mmio->end - mmio->start + 1);
+			resource_size(mmio));
 	if (!priv->iobase) {
 		dev_err(&pdev->dev, "cannot remap I/O memory space\n");
 		ret = -ENXIO;
@@ -954,7 +954,7 @@
 
 	if (netdev->mem_end) {
 		priv->membase = devm_ioremap_nocache(&pdev->dev,
-			netdev->mem_start, mem->end - mem->start + 1);
+			netdev->mem_start, resource_size(mem));
 		if (!priv->membase) {
 			dev_err(&pdev->dev, "cannot remap memory space\n");
 			ret = -ENXIO;