Re: [PATCH] rtc: rtc-omap: Replace mdelay() with msleep() in omap_rtc_power_off()

[Jia-Ju Bai]

On 2018/8/28 16:49, Johan Hovold wrote:
> On Mon, Aug 27, 2018 at 10:55:17PM +0200, Alexandre Belloni wrote:
> > Hi,
> >
> > On 30/07/2018 21:53:14+0800, Jia-Ju Bai wrote:
> > > omap_rtc_power_off() is never called in atomic context.
> > > It calls mdelay() to busily wait, which is not necessary.
> > > mdelay() can be replaced with msleep().
> > >
> > > This is found by a static analysis tool named DCNS written by myself.
> > >
> > > Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
> > > ---
> > >   drivers/rtc/rtc-omap.c | 2 +-
> > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> > > index 39086398833e..ef3d09525d0f 100644
> > > --- a/drivers/rtc/rtc-omap.c
> > > +++ b/drivers/rtc/rtc-omap.c
> > > @@ -476,7 +476,7 @@ static void omap_rtc_power_off(void)
> > >   	 * power off the system. Add a 500 ms margin for external latencies
> > >   	 * (e.g. debounce circuits).
> > >   	 */
> > > -	mdelay(2500);
> > > +	msleep(2500);
> > I'm not sure about that one because this is a poweroff function so it
> > doesn't really make sense to sleep versus busy waiting (all the drivers
> > in power/reset use mdelay())
> This power-off handler is called with interrupts disabled (as mentioned
> in the function header) and must not sleep.

Thanks for your reply :)

I check the code again, and find that you are right.
Sorry for my incorrect report.


Best wishes,
Jia-Ju Bai