Re: [PATCH] um: virtio_uml: allow probing from devicetree

From: Anton Ivanov
Date: Tue Jan 04 2022 - 09:13:43 EST




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?

If we start adding the UML devices themselves to the DT, we might as well add all of them.

In the doc patch have described the DT support as mostly for development at this point.

It can be a good alternative to the endless command line (especially for complex devices like f.e. l2tpv3).



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@xxxxxxxxxxxxx/

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.

Code looks good to me.

Thanks!


Brgds,

--
Anton R. Ivanov
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