... > + struct tegra_mc *mc = devm_tegra_get_memory_controller(dev); > + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); > > - of_node_put(args.np); > - index++; > - } > + /* An invalid mc pointer means mc and smmu drivers are not ready */ > + if (IS_ERR(mc)) > + return ERR_PTR(-EPROBE_DEFER); > > - if (!smmu) > + /* > + * IOMMU core allows -ENODEV return to carry on. So bypass any call > + * from bus_set_iommu() during tegra_smmu_probe(), as a device will > + * call in again via of_iommu_configure when fwspec is prepared. > + */ > + if (!mc->smmu || !fwspec || fwspec->ops != &tegra_smmu_ops) > return ERR_PTR(-ENODEV); > > - return &smmu->iommu; > + dev_iommu_priv_set(dev, mc->smmu); > + > + return &mc->smmu->iommu; > } Is it really okay to use devm_tegra_get_memory_controller() here? I assume it should be more preferred to do it only for devices that have fwspec->ops == &tegra_smmu_ops. Secondly, it also looks to me that a non-devm variant should be more appropriate here because tegra_smmu_probe_device() isn't invoked by the devices themselves.
