What tegra-smmu does during tegra_smmu_set_platform_dma() is actually
putting the iommu into identity mode.

Move to the new core support for ARM_DMA_USE_IOMMU by defining
ops->identity_domain.

Signed-off-by: Jason Gunthorpe<jgg@nvidia.com>
---
  drivers/iommu/tegra-smmu.c | 37 ++++++++++++++++++++++++++++++++-----
  1 file changed, 32 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 1cbf063ccf147a..f63f1d4f0bd10f 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c

@@ -511,23 +511,39 @@ static int tegra_smmu_attach_dev(struct iommu_domain *domain,
  	return err;
  }
  
-static void tegra_smmu_set_platform_dma(struct device *dev)
+static int tegra_smmu_identity_attach(struct iommu_domain *identity_domain,
+				      struct device *dev)
  {
  	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
  	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-	struct tegra_smmu_as *as = to_smmu_as(domain);
-	struct tegra_smmu *smmu = as->smmu;
+	struct tegra_smmu_as *as;
+	struct tegra_smmu *smmu;
  	unsigned int index;
  
  	if (!fwspec)
-		return;
+		return -ENODEV;
  
+	if (domain == identity_domain || !domain)
+		return 0;
+
+	as = to_smmu_as(domain);
+	smmu = as->smmu;
  	for (index = 0; index < fwspec->num_ids; index++) {
  		tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
  		tegra_smmu_as_unprepare(smmu, as);
  	}
+	return 0;
  }
  
+static struct iommu_domain_ops tegra_smmu_identity_ops = {
+	.attach_dev = tegra_smmu_identity_attach,
+};
+
+static struct iommu_domain tegra_smmu_identity_domain = {
+	.type = IOMMU_DOMAIN_IDENTITY,
+	.ops = &tegra_smmu_identity_ops,
+};
+
  static void tegra_smmu_set_pde(struct tegra_smmu_as *as, unsigned long iova,
  			       u32 value)
  {

@@ -962,11 +978,22 @@ static int tegra_smmu_of_xlate(struct device *dev,
  	return iommu_fwspec_add_ids(dev, &id, 1);
  }
  
+static int tegra_smmu_def_domain_type(struct device *dev)
+{
+	/*
+	 * FIXME: For now we want to run all translation in IDENTITY mode, due
+	 * to some device quirks. Better would be to just quirk the troubled
+	 * devices.
+	 */
+	return IOMMU_DOMAIN_IDENTITY;
+}