Re: [PATCH] Input: synaptics-rmi4 - add missed operations in remove

From: Chuhong Yuan
Date: Wed Nov 13 2019 - 03:53:15 EST


On Wed, Nov 13, 2019 at 4:23 PM Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
>
> On Wed, Nov 13, 2019 at 02:36:56PM +0800, Chuhong Yuan wrote:
> > The driver forgets to deal with work and workqueue in remove like what
> > is done when probe fails.
> > Add the missed operations to fix it.
>
> Is it really possible for the work to still be pending when fully
> registered device is properly unregistered? I thought we'd wait for
> successful data acquisition in rmi_f54_buffer_queue() before unregister
> can complete.
>

In fact, I am not familiar with the mechanism here...
I have checked other drivers with video_unregister_device and found none of
them deals with work in remove.
Therefore, I think your opinion should be right and we only need to deal with
the workqueue.

Regards,
Chuhong

> >
> > Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
> > ---
> > drivers/input/rmi4/rmi_f54.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/input/rmi4/rmi_f54.c b/drivers/input/rmi4/rmi_f54.c
> > index 710b02595486..2c0cde5c775c 100644
> > --- a/drivers/input/rmi4/rmi_f54.c
> > +++ b/drivers/input/rmi4/rmi_f54.c
> > @@ -730,6 +730,9 @@ static void rmi_f54_remove(struct rmi_function *fn)
> >
> > video_unregister_device(&f54->vdev);
> > v4l2_device_unregister(&f54->v4l2);
> > + cancel_delayed_work_sync(&f54->work);
> > + flush_workqueue(f54->workqueue);
> > + destroy_workqueue(f54->workqueue);
> > }
> >
> > struct rmi_function_handler rmi_f54_handler = {
> > --
> > 2.23.0
> >
>
> Thanks.
>
> --
> Dmitry