Re: [PATCH V2 1/3] iommu: of: Fix check for returning EPROBE_DEFER

From: Laurent Pinchart
Date: Thu May 18 2017 - 06:46:57 EST


Hi Sricharan,

Thank you for the patch.

On Thursday 18 May 2017 15:37:08 Sricharan R wrote:
> Now with IOMMU probe deferral, we return -EPROBE_DEFER
> for masters that are connected to an IOMMU which is not
> probed yet, but going to get probed, so that we can attach
> the correct dma_ops. So while trying to defer the probe of
> the master, check if the of_iommu node that it is connected
> to is marked in DT as 'status=disabled', then the IOMMU is never
> is going to get probed. So simply return NULL and let the master
> work without an IOMMU.
>
> Fixes: 7b07cbefb68d ("iommu: of: Handle IOMMU lookup failure with deferred
> probing or error") Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
> Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> Tested-by: Will Deacon <will.deacon@xxxxxxx>
> Tested-by: Magnus Damn <magnus.damn@xxxxxxxxx>
> Acked-by: Will Deacon <will.deacon@xxxxxxx>

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

> ---
> [V2] Corrected spelling/case in commit log
>
> drivers/iommu/of_iommu.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
> index 9f44ee8..e6e9bec 100644
> --- a/drivers/iommu/of_iommu.c
> +++ b/drivers/iommu/of_iommu.c
> @@ -118,6 +118,7 @@ static bool of_iommu_driver_present(struct device_node
> *np)
>
> ops = iommu_ops_from_fwnode(fwnode);
> if ((ops && !ops->of_xlate) ||
> + !of_device_is_available(iommu_spec->np) ||
> (!ops && !of_iommu_driver_present(iommu_spec->np)))
> return NULL;

--
Regards,

Laurent Pinchart