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Subject: Re: [PATCH 0/4] add xhci hooks for USB offload
To:     Howard Yen <howardyen@google.com>,
        Greg KH <gregkh@linuxfoundation.org>
Cc:     Mathias Nyman <mathias.nyman@intel.com>, robh+dt@kernel.org,
        linux-usb@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
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From:   Mathias Nyman <mathias.nyman@linux.intel.com>
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Message-ID: <f77d1149-7bd1-3914-8841-439cb67397fd@linux.intel.com>
Date:   Thu, 28 Jan 2021 08:31:14 +0200
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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?

Thanks
-Mathias