tree 236d80149511d8412c32b97465f6094564a8bb3e
parent a7b67cd5d9afb94fdcacb71b43066b8d70d1d218
author Thierry Reding <treding@nvidia.com> 1423219446 +0100
committer Joerg Roedel <jroedel@suse.de> 1424868093 +0100

iommu/omap: Play nice in multi-platform builds

The OMAP IOMMU driver unconditionally executes code and registers a
struct iommu_ops with the platform bus irrespective of whether it runs
on an OMAP SoC or not. This causes problems in multi-platform kernels
where drivers for other SoCs will no longer be able to register their
own struct iommu_ops or even try to use a struct iommu_ops for an IOMMU
that obviously isn't there.

The smallest fix I could think of is to check for the existence of any
OMAP IOMMU devices in the device tree and skip initialization otherwise.

This fixes a problem on Tegra20 where the DRM driver will try to use the
obviously non-existent OMAP IOMMU.

Reported-by: Nicolas Chauvet <kwizart@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Suman Anna <s-anna@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>