media: i2c: imx334: fix the pm runtime get logic

The PM runtime get logic is currently broken, as it checks if
ret is zero instead of checking if it is an error code,
as reported by Dan Carpenter.

While here, use the pm_runtime_resume_and_get() as added by:
commit c4a28fe77ffc ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
added pm_runtime_resume_and_get() in order to automatically handle
dev->power.usage_count decrement on errors. As a bonus, such function
always return zero on success.

It should also be noticed that a fail of pm_runtime_get_sync() would
potentially result in a spurious runtime_suspend(), instead of
using pm_runtime_put_noidle().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/i2c/imx334.c b/drivers/media/i2c/imx334.c
index 047aa7658d217e4c20fcc9e2c53cde5d4e420590..23f28606e570fbc41e27039575ecc9cebdb2c060 100644 (file)
--- a/drivers/media/i2c/imx334.c
+++ b/drivers/media/i2c/imx334.c
@@ -717,9 +717,9 @@ static int imx334_set_stream(struct v4l2_subdev *sd, int enable)
        }
 
        if (enable) {
-               ret = pm_runtime_get_sync(imx334->dev);
-               if (ret)
-                       goto error_power_off;
+               ret = pm_runtime_resume_and_get(imx334->dev);
+               if (ret < 0)
+                       goto error_unlock;
 
                ret = imx334_start_streaming(imx334);
                if (ret)
@@ -737,6 +737,7 @@ static int imx334_set_stream(struct v4l2_subdev *sd, int enable)
 
 error_power_off:
        pm_runtime_put(imx334->dev);
+error_unlock:
        mutex_unlock(&imx334->mutex);
 
        return ret;