iommu/exynos: Rework runtime PM links management

add_device is a bit more suitable for establishing runtime PM links than
the xlate callback. This change also makes it possible to implement proper
cleanup - in remove_device callback.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index f596fcc..91c548d 100644 (file)
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -263,6 +263,7 @@ struct exynos_iommu_domain {
 struct sysmmu_drvdata {
        struct device *sysmmu;          /* SYSMMU controller device */
        struct device *master;          /* master device (owner) */
+       struct device_link *link;       /* runtime PM link to master */
        void __iomem *sfrbase;          /* our registers */
        struct clk *clk;                /* SYSMMU's clock */
        struct clk *aclk;               /* SYSMMU's aclk clock */
@@ -1250,6 +1251,8 @@ static struct iommu_group *get_device_iommu_group(struct device *dev)
 
 static int exynos_iommu_add_device(struct device *dev)
 {
+       struct exynos_iommu_owner *owner = dev->archdata.iommu;
+       struct sysmmu_drvdata *data;
        struct iommu_group *group;
 
        if (!has_sysmmu(dev))
@@ -1260,6 +1263,15 @@ static int exynos_iommu_add_device(struct device *dev)
        if (IS_ERR(group))
                return PTR_ERR(group);
 
+       list_for_each_entry(data, &owner->controllers, owner_node) {
+               /*
+                * SYSMMU will be runtime activated via device link
+                * (dependency) to its master device, so there are no
+                * direct calls to pm_runtime_get/put in this driver.
+                */
+               data->link = device_link_add(dev, data->sysmmu,
+                                            DL_FLAG_PM_RUNTIME);
+       }
        iommu_group_put(group);
 
        return 0;
@@ -1268,6 +1280,7 @@ static int exynos_iommu_add_device(struct device *dev)
 static void exynos_iommu_remove_device(struct device *dev)
 {
        struct exynos_iommu_owner *owner = dev->archdata.iommu;
+       struct sysmmu_drvdata *data;
 
        if (!has_sysmmu(dev))
                return;
@@ -1283,6 +1296,9 @@ static void exynos_iommu_remove_device(struct device *dev)
                }
        }
        iommu_group_remove_device(dev);
+
+       list_for_each_entry(data, &owner->controllers, owner_node)
+               device_link_del(data->link);
 }
 
 static int exynos_iommu_of_xlate(struct device *dev,
@@ -1316,13 +1332,6 @@ static int exynos_iommu_of_xlate(struct device *dev,
        list_add_tail(&data->owner_node, &owner->controllers);
        data->master = dev;
 
-       /*
-        * SYSMMU will be runtime activated via device link (dependency) to its
-        * master device, so there are no direct calls to pm_runtime_get/put
-        * in this driver.
-        */
-       device_link_add(dev, data->sysmmu, DL_FLAG_PM_RUNTIME);
-
        return 0;
 }