RE: [PATCH] alarmtimer: Fix rebind failure

From: Biju Das
Date: Wed Sep 20 2023 - 09:31:22 EST


Hi Alexandre Belloni,

> Subject: Re: [PATCH] alarmtimer: Fix rebind failure
>
> On 20/09/2023 12:59:35+0100, Biju Das wrote:
> > The resources allocated in alarmtimer_rtc_add_device() are not freed
> > leading to re-bind failure for the endpoint driver. Fix this issue by
> > adding alarmtimer_rtc_remove_device().
> >
> > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > ---
> > This issue is found while adding irq support for built in RTC found on
> > Renesas PMIC RAA215300 device. This issue should present on all RTC
> > drivers which calls device_init_wakeup() in probe().
> > ---
> > kernel/time/alarmtimer.c | 20 ++++++++++++++++++++
> > 1 file changed, 20 insertions(+)
> >
> > diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index
> > 8d9f13d847f0..592668136bb5 100644
> > --- a/kernel/time/alarmtimer.c
> > +++ b/kernel/time/alarmtimer.c
> > @@ -61,6 +61,7 @@ static DEFINE_SPINLOCK(freezer_delta_lock);
> > /* rtc timer and device for setting alarm wakeups at suspend */
> > static struct rtc_timer rtctimer;
> > static struct rtc_device *rtcdev;
> > +static struct platform_device *rtc_pdev;
>
> This is the alarmtimer pdev, not the RTC one, right?

Yes, it is alarmtimer pdev.

Cheers,
Biju

>
> > static DEFINE_SPINLOCK(rtcdev_lock);
> >
> > /**
> > @@ -109,6 +110,7 @@ static int alarmtimer_rtc_add_device(struct device
> *dev)
> > }
> >
> > rtcdev = rtc;
> > + rtc_pdev = pdev;
> > /* hold a reference so it doesn't go away */
> > get_device(dev);
> > pdev = NULL;
> > @@ -123,6 +125,23 @@ static int alarmtimer_rtc_add_device(struct device
> *dev)
> > return ret;
> > }
> >
> > +static void alarmtimer_rtc_remove_device(struct device *dev) {
> > + struct rtc_device *rtc = to_rtc_device(dev);
> > +
> > + if (rtc_pdev) {
> > + module_put(rtc->owner);
> > + if (device_may_wakeup(rtc->dev.parent))
> > + device_init_wakeup(&rtc_pdev->dev, false);
> > +
> > + platform_device_unregister(rtc_pdev);
> > + put_device(dev);
> > + }
> > +
> > + rtcdev = NULL;
> > + rtc_pdev = NULL;
> > +}
> > +
> > static inline void alarmtimer_rtc_timer_init(void) {
> > rtc_timer_init(&rtctimer, NULL, NULL); @@ -130,6 +149,7 @@ static
> > inline void alarmtimer_rtc_timer_init(void)
> >
> > static struct class_interface alarmtimer_rtc_interface = {
> > .add_dev = &alarmtimer_rtc_add_device,
> > + .remove_dev = &alarmtimer_rtc_remove_device,
> > };
> >
> > static int alarmtimer_rtc_interface_setup(void)
> > --
> > 2.25.1
> >
>
> --
>