Subject: Re: [PATCH] um: virtio_uml: allow probing from devicetree
To:     Vincent Whitchurch <vincent.whitchurch@axis.com>,
        Johannes Berg <johannes@sipsolutions.net>
Cc:     Jeff Dike <jdike@addtoit.com>, Richard Weinberger <richard@nod.at>,
        Rob Herring <robh+dt@kernel.org>, kernel <kernel@axis.com>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-um@lists.infradead.org" <linux-um@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <20211221090447.1567-1-vincent.whitchurch@axis.com>
 <5f104044649ec60ba93648e68c3df2183e032072.camel@sipsolutions.net>
 <20211222103417.GB25135@axis.com>
From:   Anton Ivanov <anton.ivanov@cambridgegreys.com>
Organization: Cambridge Greys
Message-ID: <38342157-f9c5-42dd-db04-3a13756bd70b@cambridgegreys.com>
Date:   Wed, 22 Dec 2021 11:11:32 +0000
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On 22/12/2021 10:34, Vincent Whitchurch wrote:
> On Tue, Dec 21, 2021 at 09:48:26PM +0100, Johannes Berg wrote:
>> On Tue, 2021-12-21 at 10:04 +0100, Vincent Whitchurch wrote:
>>> Allow the virtio_uml device to be probed from the devicetree so that
>>> sub-devices can be specified using the standard virtio bindings, for
>>> example:
>>>
>>>    virtio@1 {
>>>      compatible = "virtio,uml";
>>>      socket-path = "i2c.sock";
>>>      virtio-device-id = <0x22>;
>>>
>>
>> Given this, maybe it should modify
>> Documentation/devicetree/bindings/virtio/virtio-device.yaml? Or actually
>> add a new Documentation/devicetree/bindings/virtio/uml.yaml I guess?
>>
>> +Rob, because I'm not really into any of this.
>>
>> Also, I'm not even sure we should/need to document the DT bits that are
>> basically only used for testing in the first place?
> 
> I wasn't sure either, but Rob was OK with not documenting some other
> bindings which are only used for testing[0], so I assumed that that
> applied here too:
> 
>   [0] https://lore.kernel.org/all/5baa1ae6.1c69fb81.847f2.3ab1@mx.google.com/
> 
> Also, DT bindings are supposed to be generic and based on what the
> hardware has, but here we have no hardware and something very Linux and
> UML-specific.

This will probably need to be added to the general UML documentation. I 
will take care of that once the patches are in the tree.

Brgds,

> 
>> Code looks good to me.
> 
> Thanks!
> 


-- 
Anton R. Ivanov
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