Re: [PATCH v3 18/18] drm/tegra: Use the iommu dma_owner mechanism

[Jason Gunthorpe]

On Mon, Dec 06, 2021 at 09:59:03AM +0800, Lu Baolu wrote:

> @@ -941,48 +944,44 @@ int host1x_client_iommu_attach(struct host1x_client *client)
>  	 * not the shared IOMMU domain, don't try to attach it to a different
>  	 * domain. This allows using the IOMMU-backed DMA API.
>  	 */
> -	if (domain && domain != tegra->domain)
> +	client->group = NULL;
> +	if (!client->dev->iommu_group || (domain && domain != tegra->domain))
> +		return iommu_device_set_dma_owner(client->dev,
> +						  DMA_OWNER_DMA_API, NULL);
> +
> +	if (!tegra->domain)
>  		return 0;

This if should be removed completely now

Jason