[PATCH v3 04/12] iommu/amd: Add support for enabling/disabling IOMMU features

[Vasant Hegde <vasant.hegde@amd.com>]

From: Wei Huang <wei.huang2@amd.com>

Add support for struct iommu_ops.dev_{enable/disable}_feat. Please note
that the empty feature switches will be populated by subsequent patches.

Signed-off-by: Wei Huang <wei.huang2@amd.com>
Co-developed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
---
 drivers/iommu/amd/iommu.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 39acf98e45dd..22e0703cb500 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2774,6 +2774,32 @@ static bool amd_iommu_enforce_cache_coherency(struct iommu_domain *domain)
 	return true;
 }
 
+static int amd_iommu_dev_enable_feature(struct device *dev,
+					enum iommu_dev_features feat)
+{
+	int ret;
+
+	switch (feat) {
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int amd_iommu_dev_disable_feature(struct device *dev,
+					 enum iommu_dev_features feat)
+{
+	int ret;
+
+	switch (feat) {
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
 const struct iommu_ops amd_iommu_ops = {
 	.capable = amd_iommu_capable,
 	.domain_alloc = amd_iommu_domain_alloc,
@@ -2785,6 +2811,8 @@ const struct iommu_ops amd_iommu_ops = {
 	.is_attach_deferred = amd_iommu_is_attach_deferred,
 	.pgsize_bitmap	= AMD_IOMMU_PGSIZES,
 	.def_domain_type = amd_iommu_def_domain_type,
+	.dev_enable_feat = amd_iommu_dev_enable_feature,
+	.dev_disable_feat = amd_iommu_dev_disable_feature,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
 		.attach_dev	= amd_iommu_attach_device,
 		.map_pages	= amd_iommu_map_pages,
-- 
2.31.1