[PATCH v2 4/6] iommu/exynos: Implement shutdown driver method

[Sam Protsenko <semen.protsenko@linaro.org>]

While remove method shouldn't be implemented, as it can't be done
reliably, the shutdown method can be useful for performing a kexec.
That was inspired by other IOMMU drivers, see commit 1a4e90f25b2c
("iommu/rockchip: Perform a reset on shutdown") for example.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
---
Changes in v2:
  - New patch

 drivers/iommu/exynos-iommu.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index aad845677bda..cd3f74e638f0 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -753,6 +753,16 @@ static int exynos_sysmmu_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static void exynos_sysmmu_shutdown(struct platform_device *pdev)
+{
+	struct sysmmu_drvdata *data = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+	int irq = platform_get_irq(pdev, 0);
+
+	devm_free_irq(dev, irq, data);
+	pm_runtime_force_suspend(dev);
+}
+
 static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
 {
 	struct sysmmu_drvdata *data = dev_get_drvdata(dev);
@@ -803,6 +813,7 @@ MODULE_DEVICE_TABLE(of, sysmmu_of_match);
 
 static struct platform_driver exynos_sysmmu_driver = {
 	.probe	= exynos_sysmmu_probe,
+	.shutdown = exynos_sysmmu_shutdown,
 	.driver	= {
 		.name		= "exynos-sysmmu",
 		.of_match_table	= sysmmu_of_match,
-- 
2.35.1