On Fri, Aug 13, 2021 at 3:03 PM Yong Wu <yong.wu@xxxxxxxxxxxx> wrote: > > For MM IOMMU, We always add device link between smi-common and IOMMU HW. > In mt8195, we add smi-sub-common. Thus, if the node is sub-common, we still > need find again to get smi-common, then do device link. > > Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx> > --- > drivers/iommu/mtk_iommu.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c > index a4479916ad33..a72241724adb 100644 > --- a/drivers/iommu/mtk_iommu.c > +++ b/drivers/iommu/mtk_iommu.c > @@ -845,6 +845,17 @@ static int mtk_iommu_mm_dts_parse(struct device *dev, > if (!smicomm_node) > return -EINVAL; > > + /* Find smi-common again if this is smi-sub-common */ > + if (of_property_read_bool(smicomm_node, "mediatek,smi_sub_common")) { > + of_node_put(smicomm_node); /* put the sub common */ > + > + smicomm_node = of_parse_phandle(smicomm_node, "mediatek,smi", 0); This only checks 1 level here, and does not check if the mediatek,smi of a sub-common node is not another sub-common node. So maybe add a check that the updated node here doesn't have mediatek,smi_sub_common property. > + if (!smicomm_node) { > + dev_err(dev, "sub-comm has no common.\n"); > + return -EINVAL; > + } > + } > + > plarbdev = of_find_device_by_node(smicomm_node); > of_node_put(smicomm_node); > data->smicomm_dev = &plarbdev->dev; > -- > 2.18.0 > _______________________________________________ > Linux-mediatek mailing list > Linux-mediatek@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-mediatek