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References: <20210611165937.701-1-cristian.marussi@arm.com>
 <20210611165937.701-15-cristian.marussi@arm.com>
From:   Peter Hilber <peter.hilber@opensynergy.com>
Subject: Re: [PATCH v4 14/16] firmware: arm_scmi: Add virtio transport
Message-ID: <ccc64935-08fa-d1a3-fc21-227c9d05fe24@opensynergy.com>
Date:   Thu, 1 Jul 2021 10:43:07 +0200
In-Reply-To: <20210611165937.701-15-cristian.marussi@arm.com>
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On 11.06.21 18:59, Cristian Marussi wrote:

<snip>

> +static struct virtio_driver virtio_scmi_driver = {
> +	.driver.name = "scmi-virtio",
> +	.driver.owner = THIS_MODULE,
> +	.feature_table = features,
> +	.feature_table_size = ARRAY_SIZE(features),
> +	.id_table = id_table,
> +	.probe = scmi_vio_probe,
> +	.remove = scmi_vio_remove,
> +};
> +

It might be good to also check for the VIRTIO_F_VERSION_1 feature bit in 
the optional .validate op (not yet implemented above), as some other 
devices do (quoting virtio-snd in the following):

> /**
>  * virtsnd_validate() - Validate if the device can be started.
>  * @vdev: VirtIO parent device.
>  *
>  * Context: Any context.
>  * Return: 0 on success, -EINVAL on failure.
>  */
> static int virtsnd_validate(struct virtio_device *vdev)
> {

<snip>

> 
> 	if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
> 		dev_err(&vdev->dev,
> 			"device does not comply with spec version 1.x\n");
> 		return -EINVAL;
> 	}
> 

<snip>

> 
> static struct virtio_driver virtsnd_driver = {
> 	.driver.name = KBUILD_MODNAME,
> 	.driver.owner = THIS_MODULE,
> 	.id_table = id_table,
> 	.validate = virtsnd_validate,

(end of virtio-snd quote)