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Date:   Mon, 19 Jul 2021 16:03:36 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     Rob Herring <robh+dt@kernel.org>, Jason Wang <jasowang@redhat.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Bill Mills <bill.mills@linaro.org>,
        Alex =?utf-8?Q?Benn=C3=A9e?= <alex.bennee@linaro.org>,
        "Enrico Weigelt, metux IT consult" <info@metux.net>,
        Jie Deng <jie.deng@intel.com>,
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        "open list:DRM DRIVER FOR QEMU'S CIRRUS DEVICE" 
        <virtualization@lists.linux-foundation.org>
Subject: Re: [PATCH 1/5] dt-bindings: virtio: mmio: Add support for device
 subnode
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On 14-07-21, 23:07, Arnd Bergmann wrote:
> On Wed, Jul 14, 2021 at 5:43 PM Rob Herring <robh+dt@kernel.org> wrote:
> > I guess it comes down to is 'virtio,mmio' providing a bus or is it
> > just a device? I guess a bus (so 2 nodes) does make sense here.
> > 'virtio,mmio' defines how you access/discover the virtio queues (the
> > bus) and the functional device (i2c, gpio, iommu, etc.) is accessed
> > via the virtio queues.
> 
> It's not really a bus since there is only ever one device behind it.
> A better analogy would be your 'serdev' framework: You could
> have a 8250 or a pl011 uart, and behind that have a mouse, GPS
> receiver or bluetooth dongle.
> 
> In Documentation/devicetree/bindings/serial/serial.yaml, you also
> have two nodes for a single device, so we could follow that
> example.

So two device nodes is final then ? Pretty much like how this patchset did it
already ? I need to get rid of reg thing and use "virtio,DID" though.

-- 
viresh