Commit f22c274c authored Nov 07, 2014 by Thierry Reding Committed by Matt Wagantall Jun 05, 2015

iommu/arm-smmu: Play nice on non-ARM/SMMU systems



Currently the driver registers IOMMU bus operations for all busses even
if no ARM SMMU is present on a system. Depending on the driver probing
order this prevents the driver for the real IOMMU to register itself as
the bus-wide IOMMU.

Change-Id: I345b0e922ae3d0d71622217fd869747d25ae2bb4
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Git-commit: 0e7d37adbe45404a76d05d4ef11544f23cf639dd
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>

parent aba4e0dd

drivers/iommu/arm-smmu.c

+12 −0

Original line number	Diff line number	Diff line
		@@ -2798,8 +2798,20 @@ static struct platform_driver arm_smmu_driver = {

		static int __init arm_smmu_init(void)
		{
		struct device_node *np;
		int ret;

		/*
		* Play nice with systems that don't have an ARM SMMU by checking that
		* an ARM SMMU exists in the system before proceeding with the driver
		* and IOMMU bus operation registration.
		*/
		np = of_find_matching_node(NULL, arm_smmu_of_match);
		if (!np)
		return 0;

		of_node_put(np);

		ret = platform_driver_register(&arm_smmu_driver);
		if (ret)
		return ret;