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

From: Sam Protsenko
Date: Thu Nov 03 2022 - 15:52:18 EST


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@xxxxxxxxxx>
---
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