Re: [PATCH v3 0/4] support USB offload feature

From: Jung Daehwan
Date: Mon Mar 21 2022 - 05:25:42 EST


On Mon, Mar 21, 2022 at 10:14:23AM +0100, Greg Kroah-Hartman wrote:
> On Mon, Mar 21, 2022 at 05:59:50PM +0900, Daehwan Jung wrote:
> > This patchset is for USB offload feature, which makes Co-processor to use
> > some memories of xhci. Especially it's useful for USB Audio scenario.
> > Audio stream would get shortcut because Co-processor directly write/read
> > data in xhci memories. It could get speed-up using faster memory like SRAM.
> > That's why this gives vendors flexibilty of memory management.
> > Several pathches have been merged in AOSP kernel(android12-5.10) and I put
> > together and split into 3 patches. Plus let me add user(xhci-exynos)
> > module to see how user could use it.
> >
> > To sum up, it's for providing xhci memories to Co-Processor.
> > It would cover DCBAA, Device Context, Transfer Ring, Event Ring, ERST.
> > It needs xhci hooks and to export some xhci symbols.
> >
> > Changes in v2 :
> > - Fix commit message by adding Signed-off-by in each patch.
> > - Fix conflict on latest.
> >
> > Changes in v3 :
> > - Remove export symbols and xhci hooks which xhci-exynos don't need.
> > - Modify commit message to clarify why it needs to export symbols.
> > - Check compiling of xhci-exynos.
>
> As I asked for in the previous submission, you MUST have a user for
> these hooks, otherwise we can not accept them (nor would you WANT us to
> accept them). Please fix that up and add them to the next submission as
> we can not do anything with this one.
>
> thanks,
>
> greg k-h
>

Hi greg,

I've submitted the user(xhci-exynos) together on the last patch of the patchset.
You can see xhci-exynos uses these hooks and symbols.

[PATCH v3 4/4] usb: host: add xhci-exynos driver

Best Regards,
Jung Daehwan