Fix a wrong error checking in exynos_drm_dma.c module. In the exynos_drm_register_dma function, both arm_iommu_create_mapping() and iommu_get_domain_for_dev() functions are expected to return NULL as an error. However, the error checking is performed using the statement if(IS_ERR(mapping)), which doesn't provide a suitable error value. So check if 'mapping' is NULL, and if it is, return -ENODEV. This issue[1] was reported by Dan. Changelog v1: - fix build warning. [1] https://lore.kernel.org/all/33e52277-1349-472b-a55b-ab5c3462bfcf@moroto.mountain/ Reported-by : Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Inki Dae <inki.dae@xxxxxxxxxxx> --- drivers/gpu/drm/exynos/exynos_drm_dma.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/exynos/exynos_drm_dma.c b/drivers/gpu/drm/exynos/exynos_drm_dma.c index a971590b8132..e2c7373f20c6 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dma.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dma.c @@ -107,18 +107,16 @@ int exynos_drm_register_dma(struct drm_device *drm, struct device *dev, return 0; if (!priv->mapping) { - void *mapping; + void *mapping = NULL; if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)) mapping = arm_iommu_create_mapping(&platform_bus_type, EXYNOS_DEV_ADDR_START, EXYNOS_DEV_ADDR_SIZE); else if (IS_ENABLED(CONFIG_IOMMU_DMA)) mapping = iommu_get_domain_for_dev(priv->dma_dev); - else - mapping = ERR_PTR(-ENODEV); - if (IS_ERR(mapping)) - return PTR_ERR(mapping); + if (!mapping) + return -ENODEV; priv->mapping = mapping; } -- 2.25.1