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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 30/06/2020 17:23, Krishna Reddy wrote: >>> +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. That is not what I am saying. > 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. I disagree and you should return a proper error here. >>> + 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. Ah yes, indeed. OK that's fine. Jon -- nvpublic _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel