[PATCH 1/3] crypto: stm32/hash - Properly handle pm_runtime_get failing

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Mon Jul 31 09:54:54 PDT 2023


If pm_runtime_get() (disguised as pm_runtime_resume_and_get()) fails, this
means the clk wasn't prepared and enabled. Returning early in this case
however is wrong as then the following resource frees are skipped and this
is never catched up. So do all the cleanups but clk_disable_unprepare().

Also don't emit a warning, as stm32_hash_runtime_resume() already emitted
one.

Note that the return value of stm32_hash_remove() is mostly ignored by
the device core. The only effect of returning zero instead of an error
value is to suppress another warning in platform_remove(). So return 0
even if pm_runtime_resume_and_get() failed.

Fixes: 8b4d566de6a5 ("crypto: stm32/hash - Add power management support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
 drivers/crypto/stm32/stm32-hash.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/stm32/stm32-hash.c b/drivers/crypto/stm32/stm32-hash.c
index 88a186c3dd78..75d281edae2a 100644
--- a/drivers/crypto/stm32/stm32-hash.c
+++ b/drivers/crypto/stm32/stm32-hash.c
@@ -2121,9 +2121,7 @@ static int stm32_hash_remove(struct platform_device *pdev)
 	if (!hdev)
 		return -ENODEV;
 
-	ret = pm_runtime_resume_and_get(hdev->dev);
-	if (ret < 0)
-		return ret;
+	ret = pm_runtime_get_sync(hdev->dev);
 
 	stm32_hash_unregister_algs(hdev);
 
@@ -2139,7 +2137,8 @@ static int stm32_hash_remove(struct platform_device *pdev)
 	pm_runtime_disable(hdev->dev);
 	pm_runtime_put_noidle(hdev->dev);
 
-	clk_disable_unprepare(hdev->clk);
+	if (ret >= 0)
+		clk_disable_unprepare(hdev->clk);
 
 	return 0;
 }
-- 
2.39.2




More information about the linux-arm-kernel mailing list