[PATCH v1 13/20] iommu/rockchip-iommu: Implement rk_iommu_identity_test_dev

Nicolin Chen
2025-10-13T00:06:25Z

Move sanity and compatibility tests from the attach_dev callback to the
new test_dev callback function. The IOMMU core makes sure an attach_dev
call must be invoked after a successful test_dev call.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/rockchip-iommu.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 85f3667e797c3..89cb65f76fe52 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -959,20 +959,25 @@ static int rk_iommu_enable(struct rk_iommu *iommu)
return ret;
}

+static int rk_iommu_identity_test_dev(struct iommu_domain *domain,
+ struct device *dev, ioasid_t pasid,
+ struct iommu_domain *old)
+{
+ /* Allow 'virtual devices' (eg drm) to detach from domain */
+ if (!rk_iommu_from_dev(dev))
+ return -ENODEV;
+ return 0;
+}
+
static int rk_iommu_identity_attach(struct iommu_domain *identity_domain,
struct device *dev,
struct iommu_domain *old)
{
- struct rk_iommu *iommu;
+ struct rk_iommu *iommu = rk_iommu_from_dev(dev);
struct rk_iommu_domain *rk_domain;
unsigned long flags;
int ret;

- /* Allow 'virtual devices' (eg drm) to detach from domain */
- iommu = rk_iommu_from_dev(dev);
- if (!iommu)
- return -ENODEV;
-
rk_domain = to_rk_domain(iommu->domain);

dev_dbg(dev, "Detaching from iommu domain\n");
@@ -997,6 +1002,7 @@ static int rk_iommu_identity_attach(struct iommu_domain *identity_domain,
}

static struct iommu_domain_ops rk_identity_ops = {
+ .test_dev = rk_iommu_identity_test_dev,
.attach_dev = rk_iommu_identity_attach,
};

--
2.43.0