On 10/06/2019 14:55, Yong Wu wrote: > 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 6fe3369..f7599d8 100644 > --- a/drivers/iommu/mtk_iommu.c > +++ b/drivers/iommu/mtk_iommu.c > @@ -664,7 +664,7 @@ 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) { can't we use: device_lock() device_is_bound(struct device *dev) device_unlock() > of_node_put(larbnode); > return -EPROBE_DEFER; > } > diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c > index 0b0908c..c43c4a0 100644 > --- a/drivers/iommu/mtk_iommu_v1.c > +++ b/drivers/iommu/mtk_iommu_v1.c > @@ -604,7 +604,7 @@ 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; > } >