RE: [PATCH] alarmtimer: Fix rebind failure

[Biju Das]

> Subject: RE: [PATCH] alarmtimer: Fix rebind failure
> 
> 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.


OK, I will change it to alarmtimer_pdev to avoid confusion.

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
> > >
> >
> > --
> >