From mboxrd@z Thu Jan 1 00:00:00 1970 From: balbi@kernel.org (Felipe Balbi) Date: Wed, 07 Sep 2016 13:47:22 +0300 Subject: [PATCH] usb: dwc3: host: inherit dma configuration from parent dev In-Reply-To: <75ca65eb-e8c4-bc3f-e00b-b0cba46d28c6@arm.com> References: <5844875.KucAoPMrXi@wuerfel> <20160907063313.GA13903@b29397-desktop> <12021424.cItk3A7CfE@wuerfel> <20160907095549.GD13903@b29397-desktop> <75ca65eb-e8c4-bc3f-e00b-b0cba46d28c6@arm.com> Message-ID: <874m5skmv9.fsf@linux.intel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, Robin Murphy writes: > On 07/09/16 10:55, Peter Chen wrote: > [...] >>> Regarding the DMA configuration that you mention in ci_hdrc_add_device(), >>> I think we should replace >>> >>> pdev->dev.dma_mask = dev->dma_mask; >>> pdev->dev.dma_parms = dev->dma_parms; >>> dma_set_coherent_mask(&pdev->dev, dev->coherent_dma_mask); >>> >>> with of_dma_configure(), which has the chance to configure more than >>> just those three, as the dma API might look into different aspects: >>> >>> - iommu specific configuration >>> - cache coherency information >>> - bus type >>> - dma offset >>> - dma_map_ops pointer >>> >>> We try to handle everything in of_dma_configure() at configuration >>> time, and that would be the place to add anything else that we might >>> need in the future. >>> >> >> Yes, I agree with you, but just like Felipe mentioned, we also need to >> consider PCI device, can we do something like gpiod_get_index does? Are >> there any similar APIs like of_dma_configure for ACPI? > > Not yet, but Lorenzo has one in progress[1], primarily for the sake of > abstracting away the IOMMU configuration. > > Robin. > > [1]:http://www.mail-archive.com/linux-kernel at vger.kernel.org/msg1209911.html not exported for drivers to use. If Lorenzo is trying to making a matching API for ACPI systems, then it needs to follow what of_dma_configure() is doing, and add an EXPORT_SYMBOL_GPL() -- balbi -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 800 bytes Desc: not available URL: