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Date:   Thu, 28 Jan 2021 08:41:25 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Mathias Nyman <mathias.nyman@linux.intel.com>
Cc:     Howard Yen <howardyen@google.com>,
        Mathias Nyman <mathias.nyman@intel.com>, robh+dt@kernel.org,
        linux-usb@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/4] add xhci hooks for USB offload
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On Thu, Jan 28, 2021 at 08:31:14AM +0200, Mathias Nyman wrote:
> On 28.1.2021 5.38, Howard Yen wrote:
> > On Tue, Jan 26, 2021 at 10:19 PM Greg KH <gregkh@linuxfoundation.org> wrote:
> >>
> >> On Fri, Jan 22, 2021 at 05:32:58PM +0200, Mathias Nyman wrote:
> >>>
> >>> Ok, before adding hooks like this I think we need to see how they are used.
> >>> Do you have the rest of the patches that go on top of this series?
> >>>
> >>> Maybe it could make sense to use overrides for the functions in struct hc_driver
> >>> instead in some cases? There is support for that already.
> >>
> >> What overrides could be done for these changes?  At first glance that
> >> would seem to require a lot of duplicated code in whatever override
> >> happens to be needed.
> >>
> >> thanks,
> >>
> >> greg k-h
> > 
> > This patch series is all the changes for the offload hooks currently.
> > 
> > I thought about this, but if I tried to override the functions in
> > struct hc_driver, that'll need to
> > copy many code to the override function, and it won't follow the
> > latest change in the core
> > xhci driver.
> > 
> > 
> > - Howard
> 
> Ok, I see. 
> 
> The point I'm trying to make is that there is no way for me to know if
> these hooks are the right solution before I see any code using them.
> 
> Is the offloading code ready and public somewhere?

There is offload code published in the last few Samsung phone kernels, I
want to get that ported to these hooks to see if that works properly.

Give me a few days and I'll see if I can get it working, I had a
half-finished port around here somewhere...

thanks,

greg k-h