[RFC PATCH v2 00/22] Introduce QC USB SND audio offloading support

[Mathias Nyman]

On 26.1.2023 5.14, Wesley Cheng wrote:
> Changes in v2:
> 
> XHCI:
> - Replaced XHCI and HCD changes with Mathias' XHCI interrupter changes
> in his tree:
> https://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git/log/?h=feature_interrupters
> 

I'll submit the first three patches from that branch myself to usb-next, might modify
them slightly.
Just need to make sure they don't cause regression. Those are changes I want done anyway.

> Adjustments made to Mathias' changes:
>    - Created xhci-intr.h to export/expose interrupter APIs versus exposing xhci.h.
>      Moved dependent structures to this file as well. (so clients can parse out
>      information from "struct xhci_interrupter")
>    - Added some basic locking when requesting interrupters.
>    - Fixed up some sanity checks.
>    - Removed clearing of the ERSTBA during freeing of the interrupter. (pending
>      issue where SMMU fault occurs if DMA addr returned is 64b - TODO)

Was this solvable by first clearing high 32 bits and then low 32 bits?

Thanks
Mathias