drivers: iommu: add workaround for multiple suspend/resume calls

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 76f423d..78c91c9 100644 (file)
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -183,6 +183,7 @@ struct sysmmu_drvdata {
        spinlock_t lock;
        struct iommu_domain *domain;
        bool runtime_active;
+       bool suspended;
        unsigned long pgtable;
        void __iomem *sfrbase;
 };
@@ -383,6 +384,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
 
 static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
 {
+       if (data->suspended)
+               return;
+
+       data->suspended = 1;
        clk_enable(data->clk_master);
 
        __raw_writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
@@ -438,6 +443,11 @@ static void __sysmmu_init_config(struct sysmmu_drvdata *data)
 
 static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
 {
+       if (!data->suspended)
+               return;
+
+       data->suspended = 0;
+
        clk_enable(data->clk_master);
        clk_enable(data->clk);
 
@@ -634,6 +644,7 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
        }
 
        data->runtime_active = !pm_runtime_enabled(dev);
+       data->suspended = 1;
 
        spin_lock_init(&data->lock);
        INIT_LIST_HEAD(&data->node);