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Date:   Fri, 31 Jan 2020 10:06:50 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Benjamin GAIGNARD <benjamin.gaignard@st.com>
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Subject: Re: [PATCH v2 2/7] bus: Introduce firewall controller framework
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On Fri, Jan 31, 2020 at 08:37:27AM +0000, Benjamin GAIGNARD wrote:
> 
> On 1/29/20 12:17 PM, Mark Brown wrote:
> > On Wed, Jan 29, 2020 at 10:52:40AM +0100, Greg KH wrote:
> >
> >> It just needs to be part of the bus logic for the specific bus that this
> >> "firewall" is on.  Just like we do the same thing for USB or thunderbolt
> >> devices.  Put this in the bus-specific code please.
> > I'd expect that this is going to affect at least platform and AMBA
> > buses.
> 
> Correct me if I'm wrong but creating a new type of bus would mean
> that all the drivers living on this bus must be changed to register 
> themselves on this bus ?

Yes.

> Or does a solution exist to let them live on the platform bus and call 
> firewalled bus before been probed ?

Why do people want to abuse the platform bus so much?  If a device is on
a bus that can have such a controller, then it is on a real bus, use it!

> All the impacted drivers could work on the existing bus with or without 
> the firewall so I don't want to break

break what?

> 
> that.

Odd line-break :)

Just register the driver on both busses, no big deal.

Stop abusing the platform bus code for things that it is not for.

thanks,

greg k-h