>> +struct arm_smmu_device *nvidia_smmu_impl_init(struct arm_smmu_device >> +*smmu) { >> + unsigned int i; .... >> + for (i = 1; i < MAX_SMMU_INSTANCES; i++) { >> + struct resource *res; >> + >> + res = platform_get_resource(pdev, IORESOURCE_MEM, i); >> + if (!res) >> + break; >Currently this driver is only supported for Tegra194 which I understand has 3 SMMUs. Therefore, I don't feel that we should fail silently here, I think it is better to return an error if all 3 cannot be initialised. Initialization of all the three SMMU instances is not necessary here. The driver can work with all the possible number of instances 1, 2 and 3 based on the DT config though it doesn't make much sense to use it with 1 instance. There is no silent failure here from driver point of view. If there is misconfig in DT, SMMU faults would catch issues. >> + nvidia_smmu->bases[i] = devm_ioremap_resource(smmu->dev, res); >> + if (IS_ERR(nvidia_smmu->bases[i])) >> + return ERR_CAST(nvidia_smmu->bases[i]); >You want to use PTR_ERR() here. PTR_ERR() returns long integer. This function returns a pointer. ERR_CAST is the right one to use here. -- nvpublic