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Date: Thu, 1 Feb 2024 10:06:41 -0800
From: Greg KH <gregkh@linuxfoundation.org>
To: Guan-Yu Lin <guanyulin@google.com>
Cc: Oliver Neukum <oneukum@suse.com>,
	Alan Stern <stern@rowland.harvard.edu>, mathias.nyman@intel.com,
	royluo@google.com, hadess@hadess.net, benjamin.tissoires@redhat.com,
	heikki.krogerus@linux.intel.com, grundler@chromium.org,
	yajun.deng@linux.dev, dianders@chromium.org,
	linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
	badhri@google.com, albertccwang@google.com, pumahsu@google.com
Subject: Re: [PATCH] [RFC] usb: host: Allow userspace to control usb suspend
 flows
Message-ID: <2024020106-gore-cohesive-4bb3@gregkh>
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On Fri, Feb 02, 2024 at 12:00:00AM +0800, Guan-Yu Lin wrote:
> On Thu, Feb 1, 2024 at 5:38 PM Oliver Neukum <oneukum@suse.com> wrote:
> >
> >
> >
> > On 01.02.24 10:02, Guan-Yu Lin wrote:
> > > On Wed, Jan 31, 2024 at 1:12 AM Alan Stern <stern@rowland.harvard.edu> wrote:
> > >>
> > >> On Tue, Jan 30, 2024 at 06:47:13AM +0000, Guan-Yu Lin wrote:
> >
> > >> Why does this affect only the USB subsystem?  Can't the co-processor
> > >> use other, non-USB, devices on the system?
> > >>
> > > In our use case, the co-processor only supports USB subsystem. There might be
> > > other co-processors support more subsystems, but we're not sure about how they
> > > will interact with the system.
> >
> > Hi,
> >
> > it would be very good if you decided this now, before we add attributes.
> >
> > The reason is that if this feature is needed for multiple subsystems,
> > the attribute should be added to the generic device structure, so that
> > the naming and semantics are consistent.
> > You really don't want to repeat this discussion for every subsystem.
> >
> >         Regards
> >                 Oliver
> >
> 
> Hi,
> 
> Given that in our use case the co-processor only supports USB subsystem, I'd
> like to proceed with adding the attribute exclusively within the USB subsystem.
> Please let me know if there is any further consideration, thanks.

Please do it properly as Oliver states here.  Otherwise it will require
more work in the future for you to modify this again for all other
subsystems.

thanks,

greg k-h