[PATCH] crypto: rockchip: fix autosuspend cleanup during teardown

[Guangshuo Li]

rk_crypto_pm_init() calls pm_runtime_use_autosuspend(), but the
autosuspend setting is not undone if pm_runtime_set_suspended() fails
or when runtime PM is later torn down by rk_crypto_pm_exit().

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 cleanup, this reference is not dropped and usage_count remains
unbalanced.

Undo the autosuspend setting when pm_runtime_set_suspended() fails and
in rk_crypto_pm_exit() before disabling runtime PM.

This issue was found by manual code inspection.

Fixes: a216be3964c1 ("crypto: rockchip - introduce PM")
Cc: stable at vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244 at gmail.com>
---
 drivers/crypto/rockchip/rk3288_crypto.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/rockchip/rk3288_crypto.c b/drivers/crypto/rockchip/rk3288_crypto.c
index b77bdce8e7fc..cfca472f996f 100644
--- a/drivers/crypto/rockchip/rk3288_crypto.c
+++ b/drivers/crypto/rockchip/rk3288_crypto.c
@@ -150,14 +150,17 @@ static int rk_crypto_pm_init(struct rk_crypto_info *rkdev)
 	pm_runtime_set_autosuspend_delay(rkdev->dev, 2000);
 
 	err = pm_runtime_set_suspended(rkdev->dev);
-	if (err)
+	if (err) {
+		pm_runtime_dont_use_autosuspend(rkdev->dev);
 		return err;
+	}
 	pm_runtime_enable(rkdev->dev);
 	return err;
 }
 
 static void rk_crypto_pm_exit(struct rk_crypto_info *rkdev)
 {
+	pm_runtime_dont_use_autosuspend(rkdev->dev);
 	pm_runtime_disable(rkdev->dev);
 }
 
-- 
2.43.0