[PATCH] crypto: stm32/cryp: fix autosuspend cleanup during teardown

[Guangshuo Li]

stm32_cryp_probe() calls pm_runtime_use_autosuspend(), but neither the
probe failure path nor stm32_cryp_remove() calls the matching
pm_runtime_dont_use_autosuspend() before disabling runtime PM.

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 and usage_count remains
unbalanced.

Add the missing pm_runtime_dont_use_autosuspend() calls to both the
probe failure and remove paths before disabling runtime PM.

This issue was found by manual code inspection.

Fixes: 65f9aa36ee47 ("crypto: stm32/cryp - Add power management support")
Cc: stable at vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244 at gmail.com>
---
 drivers/crypto/stm32/stm32-cryp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c
index b79877099942..74f6e329b1fa 100644
--- a/drivers/crypto/stm32/stm32-cryp.c
+++ b/drivers/crypto/stm32/stm32-cryp.c
@@ -2691,6 +2691,7 @@ static int stm32_cryp_probe(struct platform_device *pdev)
 		dma_release_channel(cryp->dma_lch_out);
 err_dma:
 err_rst:
+	pm_runtime_dont_use_autosuspend(dev);
 	pm_runtime_disable(dev);
 	pm_runtime_put_noidle(dev);
 
@@ -2722,6 +2723,7 @@ static void stm32_cryp_remove(struct platform_device *pdev)
 	if (cryp->dma_lch_out)
 		dma_release_channel(cryp->dma_lch_out);
 
+	pm_runtime_dont_use_autosuspend(cryp->dev);
 	pm_runtime_disable(cryp->dev);
 	pm_runtime_put_noidle(cryp->dev);
 
-- 
2.43.0