[PATCH 4/7] iommu: Add driver-not-bound notification

[Alex Williamson <alex.williamson@redhat.com>]

The driver core supports a BUS_NOTIFY_DRIVER_NOT_BOUND notification
sent if a driver fails to bind to a device.  Extend IOMMU group
notifications to include a version of this.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
---
 drivers/iommu/iommu.c |    2 ++
 include/linux/iommu.h |    1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3b67144dead2..cf6051db4208 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1113,6 +1113,8 @@ static int iommu_bus_notifier(struct notifier_block *nb,
 	case BUS_NOTIFY_UNBOUND_DRIVER:
 		group_action = IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER;
 		break;
+	case BUS_NOTIFY_DRIVER_NOT_BOUND:
+		group_action = IOMMU_GROUP_NOTIFY_DRIVER_NOT_BOUND;
 	}
 
 	if (group_action)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 2e4de0deee53..54a0eb96da25 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -268,6 +268,7 @@ static inline void iommu_device_set_fwnode(struct iommu_device *iommu,
 #define IOMMU_GROUP_NOTIFY_BOUND_DRIVER		4 /* Post Driver bind */
 #define IOMMU_GROUP_NOTIFY_UNBIND_DRIVER	5 /* Pre Driver unbind */
 #define IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER	6 /* Post Driver unbind */
+#define IOMMU_GROUP_NOTIFY_DRIVER_NOT_BOUND	7 /* Driver bind failed */
 
 extern int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops);
 extern bool iommu_present(struct bus_type *bus);