The iommu consumer should use device_link to connect with the smi-larb(supplier). then the smi-larb should run before the iommu consumer. Here we delay the iommu driver until the smi driver is ready, then all the iommu consumer always is after the smi driver. When there is no this patch, if some consumer drivers run before smi-larb, the supplier link_status is DL_DEV_NO_DRIVER(0) in the device_link_add, then device_links_driver_bound will use WARN_ON to complain that the link_status of supplier is not right. This is a preparing patch for adding device_link. Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> --- drivers/iommu/mtk_iommu.c | 2 +- drivers/iommu/mtk_iommu_v1.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 36526c9..202e41b 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -645,7 +645,7 @@ static int mtk_iommu_probe(struct platform_device *pdev) id = i; plarbdev = of_find_device_by_node(larbnode); - if (!plarbdev) + if (!plarbdev || !plarbdev->dev.driver) return -EPROBE_DEFER; data->smi_imu.larb_imu[id].dev = &plarbdev->dev; diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index f8b8275..9386aee 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -601,7 +601,7 @@ static int mtk_iommu_probe(struct platform_device *pdev) plarbdev = of_platform_device_create( larb_spec.np, NULL, platform_bus_type.dev_root); - if (!plarbdev) { + if (!plarbdev || !plarbdev->dev.driver) { of_node_put(larb_spec.np); return -EPROBE_DEFER; } -- 1.9.1