Re: [PATCH v3 2/2] usb:dwc3: pass arch data to xhci-hcd child

From: Grygorii Strashko
Date: Wed Mar 30 2016 - 09:53:09 EST

On 03/30/2016 04:10 PM, Felipe Balbi wrote:
> "Thang Q. Nguyen" <tqnguyen@xxxxxxx> writes:
>> [ text/plain ]
>> From: "Thang Q. Nguyen" <tqnguyen@xxxxxxx>
>> The xhci-hcd child node needs to inherit archdata attribute to use
>> dma_ops functions and attributes. This patch enables the USB DWC3
>> driver to pass archdata attributes to its xhci-hcd child node.
>> Changes from v2:
>> - None
>> Changes from v1:
>> - None
> changes should be between tearline and diffstat.

uh. This become a real problem :(, especially with LPAE enabled.
DMA properties need to be inherited not only here, but also in
usb_add_gadget_udc_release(). And probably in other places
where devices are created manually - the worst case : device is created
manually but doesn't belong to any bus.

And DMA configuration must include dma_pfn_offset also!
And how about iommu staff?

FYI. Solution used for PCI
c49b8fc of/pci: Add of_pci_dma_configure() to update DMA configuration

Rejected: introduce dma_init_dev_from_parent() or smth. like this