Re: [PATCH v2 4/6] gpio: cdev: wake up chardev poll() on device unbind
From: Bartosz Golaszewski
Date: Mon Aug 21 2023 - 09:04:07 EST
On Mon, Aug 21, 2023 at 2:43 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
>
> On Fri, Aug 18, 2023 at 12:31 PM Andy Shevchenko
> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> >
> > On Thu, Aug 17, 2023 at 08:49:56PM +0200, Bartosz Golaszewski wrote:
> > > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> > >
> > > Add a notifier block to the gpio_chardev_data structure and register it
> > > with the gpio_device's device notifier. Upon reception of an event, wake
> > > up the wait queue so that the user-space be forced out of poll() and need
> > > to go into a new system call which will then fail due to the chip being
> > > gone.
> >
> > ...
> >
> > > + struct gpio_chardev_data *cdev = container_of(nb,
> > > + struct gpio_chardev_data,
> > > + device_unregistered_nb);
> >
> > struct gpio_chardev_data *cdev =
> > container_of(nb, struct gpio_chardev_data, device_unregistered_nb);
> >
> > ?
>
> I could live with the other version but sure, why not.
>
> I will send a v3 with a helper wrapper around
> blocking_notifier_call_chain() for more brevity.
>
Scratch that, I need coffee. This was supposed to go under the line
state notifications patch.
Bart