[PATCH v2 30/42][SRU][U] iommu/exynos: Use first SYSMMU in controllers list for IOMMU core

[You-Sheng Yang]

From: Joerg Roedel <jroedel at suse.de>

BugLink: https://bugs.launchpad.net/bugs/1876707

On Exynos platforms there can be more than one SYSMMU (IOMMU) for one
DMA master device. Since the IOMMU core code expects only one hardware
IOMMU, use the first SYSMMU in the list.

Signed-off-by: Joerg Roedel <jroedel at suse.de>
Tested-by: Marek Szyprowski <m.szyprowski at samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski at samsung.com>
Link: https://lore.kernel.org/r/20200429133712.31431-31-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel at suse.de>
(cherry picked from commit 66ae88e71ecb93bafaacaeef233971eacd10e749
linux-next)
Signed-off-by: You-Sheng Yang <vicamo.yang at canonical.com>
---
 drivers/iommu/exynos-iommu.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 186ff5cc975c..09cdd163560a 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -1261,6 +1261,11 @@ static int exynos_iommu_add_device(struct device *dev)
 	}
 	iommu_group_put(group);
 
+	/* There is always at least one entry, see exynos_iommu_of_xlate() */
+	data = list_first_entry(&owner->controllers,
+				struct sysmmu_drvdata, owner_node);
+	iommu_device_link(&data->iommu, dev);
+
 	return 0;
 }
 
@@ -1286,6 +1291,11 @@ static void exynos_iommu_remove_device(struct device *dev)
 
 	list_for_each_entry(data, &owner->controllers, owner_node)
 		device_link_del(data->link);
+
+	/* There is always at least one entry, see exynos_iommu_of_xlate() */
+	data = list_first_entry(&owner->controllers,
+				struct sysmmu_drvdata, owner_node);
+	iommu_device_unlink(&data->iommu, dev);
 }
 
 static int exynos_iommu_of_xlate(struct device *dev,
-- 
2.25.1