Hi Martin, Thank you for the patch. On Wed, Apr 05, 2023 at 11:29:03AM +0200, Martin Kepplinger wrote: > pm_runtime_get_if_in_use() does not only return nonzero values when > the device is in use, it can return a negative errno too. > > And especially during resuming from system suspend, when runtime pm > is not yet up again, this can very well happen. And in such a case > the subsequent pm_runtime_put() call would result in a refcount underflow! > > Fix it by correctly using pm_runtime_get_if_in_use(). > > Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > --- > drivers/media/i2c/hi846.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/media/i2c/hi846.c b/drivers/media/i2c/hi846.c > index 5b5ea5425e984..0b0eda2e223cd 100644 > --- a/drivers/media/i2c/hi846.c > +++ b/drivers/media/i2c/hi846.c > @@ -1544,7 +1544,7 @@ static int hi846_set_ctrl(struct v4l2_ctrl *ctrl) > exposure_max); > } > > - if (!pm_runtime_get_if_in_use(&client->dev)) > + if (pm_runtime_get_if_in_use(&client->dev) <= 0) > return 0; > > switch (ctrl->id) { -- Regards, Laurent Pinchart