diff --git a/drivers/gpu/drm/shmobile/shmob_drm_drv.c b/drivers/gpu/drm/shmobile/shmob_drm_drv.c
index 592572554eb0..58d8a98c749b 100644
--- a/drivers/gpu/drm/shmobile/shmob_drm_drv.c
+++ b/drivers/gpu/drm/shmobile/shmob_drm_drv.c
@@ -233,8 +233,8 @@ static int shmob_drm_probe(struct platform_device *pdev)
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	sdev->mmio = devm_ioremap_resource(&pdev->dev, res);
-	if (sdev->mmio == NULL)
-		return -ENOMEM;
+	if (IS_ERR(sdev->mmio))
+		return PTR_ERR(sdev->mmio);
 
 	ret = shmob_drm_setup_clocks(sdev, pdata->clk_source);
 	if (ret < 0)