On Mon, May 23, 2022 at 10:43:20AM +0200, Linus Walleij wrote:
> On Mon, May 23, 2022 at 10:40 AM Uwe Kleine-König
> <u.kleine-koenig@xxxxxxxxxxxxxx> wrote:
>
> > If the teardown callback failed in the gpio driver, it fails to free the
> > irq (if there is one). The device is removed anyhow. If later on the irq
> > triggers, all sorts of unpleasant things might happen (e.g. accessing
> > the struct adp5588_gpio which is already freed in the meantime or starting
> > i2c bus transfers for an unregistered device). Even before irq support was
> > added to this driver, exiting early was wrong; back then it failed to
> > unregister the gpiochip.
> >
> > Fortunately these callbacks aren't used any more since at least blackfin
> > was removed in 2018. So just drop them.
> >
> > Note that they are not removed from struct adp5588_gpio_platform_data
> > because the keyboard driver adp5588-keys.c also makes use of them.
> > (I didn't check if the callbacks might have been called twice, maybe there
> > is another reason hidden to better not call these functions.)
> >
> > This patch is a preparation for making i2c remove callbacks return void.
> >
> > Fixes: 80884094e344 ("gpio: adp5588-gpio: new driver for ADP5588 GPIO expanders")
> > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
>
> Good riddance!
> But also remove the setup and teardown prototypes in
> include/linux/platform_data/adp5588.h
Please reread the commit log. They were not remove on purpose. If you
missed that part, you also missed half of the "fun". :-P
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
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