[PATCH] media: i2c: imx290: fix runtime PM reference handling on probe errors

[Guangshuo Li]

imx290_probe() takes an initial runtime PM reference with
pm_runtime_get_noresume(). Historically, the probe error path balanced
that reference with pm_runtime_put_noidle().

The change that moved the successful-path pm_runtime_put_autosuspend()
into imx290_subdev_init() made the initial runtime PM reference get
dropped once imx290_subdev_init() is called.

The longest probe error path, however, still falls through to err_pm
and calls pm_runtime_put_noidle(). Failures from imx290_subdev_init()
or v4l2_async_register_subdev() therefore decrement the runtime PM
usage count a second time.

Move pm_runtime_put_noidle() to the imx290_stop_streaming() failure
path, which is the only error path taken before imx290_subdev_init()
drops the initial runtime PM reference.

This issue was found by manual code inspection.

Fixes: a92651b8e288 ("media: i2c: imx290: Avoid communication during probe()")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
---
 drivers/media/i2c/imx290.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
index 21cbc81cb2ed..c2cdb1557dea 100644
--- a/drivers/media/i2c/imx290.c
+++ b/drivers/media/i2c/imx290.c
@@ -1634,6 +1634,7 @@ static int imx290_probe(struct i2c_client *client)
 	ret = imx290_stop_streaming(imx290);
 	if (ret) {
 		ret = dev_err_probe(dev, ret, "Could not initialize device\n");
+		pm_runtime_put_noidle(dev);
 		goto err_pm;
 	}
 
@@ -1662,7 +1663,6 @@ static int imx290_probe(struct i2c_client *client)
 	imx290_subdev_cleanup(imx290);
 err_pm:
 	pm_runtime_disable(dev);
-	pm_runtime_put_noidle(dev);
 	imx290_power_off(imx290);
 	return ret;
 }
-- 
2.43.0