In case of error, the function devm_ioremap_resource() returns ERR_PTR() and never returns NULL. The NULL test in the return value check should be replaced with IS_ERR(). Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx> --- drivers/gpu/drm/shmobile/shmob_drm_drv.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/shmobile/shmob_drm_drv.c b/drivers/gpu/drm/shmobile/shmob_drm_drv.c index 5925725..58d8a98 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)