[PATCH] drm/tegra: nvdec: fix autosuspend cleanup during teardown

[Guangshuo Li]

nvdec_probe() calls pm_runtime_use_autosuspend(), but nvdec_remove()
does not call the matching pm_runtime_dont_use_autosuspend() during
teardown.

If the autosuspend delay is set to a negative value while autosuspend
is enabled, the runtime PM core increments usage_count to prevent
runtime suspend. Without calling pm_runtime_dont_use_autosuspend()
during teardown, this reference is not dropped.

The documentation for pm_runtime_use_autosuspend() also notes that it
is important to undo it with pm_runtime_dont_use_autosuspend() at
driver exit time, unless runtime PM was initially enabled with
devm_pm_runtime_enable().

Add the missing pm_runtime_dont_use_autosuspend() call to the driver
remove path.

This issue was found by manual code inspection.

Fixes: 62fa0a985e2c ("drm/tegra: Enable runtime PM during probe")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
---
 drivers/gpu/drm/tegra/nvdec.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/tegra/nvdec.c b/drivers/gpu/drm/tegra/nvdec.c
index 7a38664e890e..cb52459b2d79 100644
--- a/drivers/gpu/drm/tegra/nvdec.c
+++ b/drivers/gpu/drm/tegra/nvdec.c
@@ -546,6 +546,7 @@ static void nvdec_remove(struct platform_device *pdev)
 {
 	struct nvdec *nvdec = platform_get_drvdata(pdev);
 
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	host1x_client_unregister(&nvdec->client.base);
 	falcon_exit(&nvdec->falcon);
-- 
2.43.0