From 05b0c4ab7407f952951fd4dfaf6c846a3928f202 Mon Sep 17 00:00:00 2001
From: Hiroshi Doyu <hdoyu@nvidia.com>
Date: Thu, 24 Jan 2013 15:16:57 +0200
Subject: [PATCH] --- yaml --- r: 358818 b: refs/heads/master c:
 6fe367580339a3adf77273d4366652665319bdeb h: refs/heads/master v: v3

---
 [refs]                                 |  2 +-
 trunk/arch/arm/include/asm/dma-iommu.h |  1 +
 trunk/arch/arm/mm/dma-mapping.c        | 25 +++++++++++++++++++++++++
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index e7e8b61a1331..67ee017af018 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fab112a394b9cf5e3bf888af6ff5076ba9fa0f06
+refs/heads/master: 6fe367580339a3adf77273d4366652665319bdeb
diff --git a/trunk/arch/arm/include/asm/dma-iommu.h b/trunk/arch/arm/include/asm/dma-iommu.h
index 666d8a8c3a2b..a8c56acc8c98 100644
--- a/trunk/arch/arm/include/asm/dma-iommu.h
+++ b/trunk/arch/arm/include/asm/dma-iommu.h
@@ -30,6 +30,7 @@ void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping);
 
 int arm_iommu_attach_device(struct device *dev,
 					struct dma_iommu_mapping *mapping);
+void arm_iommu_detach_device(struct device *dev);
 
 #endif /* __KERNEL__ */
 #endif
diff --git a/trunk/arch/arm/mm/dma-mapping.c b/trunk/arch/arm/mm/dma-mapping.c
index d91c4880f559..6563e3872659 100644
--- a/trunk/arch/arm/mm/dma-mapping.c
+++ b/trunk/arch/arm/mm/dma-mapping.c
@@ -1848,4 +1848,29 @@ int arm_iommu_attach_device(struct device *dev,
 	return 0;
 }
 
+/**
+ * arm_iommu_detach_device
+ * @dev: valid struct device pointer
+ *
+ * Detaches the provided device from a previously attached map.
+ * This voids the dma operations (dma_map_ops pointer)
+ */
+void arm_iommu_detach_device(struct device *dev)
+{
+	struct dma_iommu_mapping *mapping;
+
+	mapping = to_dma_iommu_mapping(dev);
+	if (!mapping) {
+		dev_warn(dev, "Not attached\n");
+		return;
+	}
+
+	iommu_detach_device(mapping->domain, dev);
+	kref_put(&mapping->kref, release_iommu_mapping);
+	mapping = NULL;
+	set_dma_ops(dev, NULL);
+
+	pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));
+}
+
 #endif