Messages in this thread | | | Date | Thu, 30 Aug 2018 00:44:56 +0200 | From | Sebastian Reichel <> | Subject | Re: [PATCH] power: reset: piix4-poweroff: Replace mdelay() with msleep() and usleep_range() in piix4_poweroff() |
| |
Hi,
On Mon, Jul 30, 2018 at 09:48:38PM +0800, Jia-Ju Bai wrote: > piix4_poweroff() is never called in atomic context. > It calls mdelay() to busily wait, which is not necessary. > mdelay() can be replaced with msleep() and usleep_range(). > > This is found by a static analysis tool named DCNS written by myself. > > Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> > ---
This is a shutdown driver, so busy waiting is ok.
-- Sebastian
> drivers/power/reset/piix4-poweroff.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/power/reset/piix4-poweroff.c b/drivers/power/reset/piix4-poweroff.c > index 20ce3ff5e039..5d4c72992d2c 100644 > --- a/drivers/power/reset/piix4-poweroff.c > +++ b/drivers/power/reset/piix4-poweroff.c > @@ -47,7 +47,7 @@ static void piix4_poweroff(void) > io_offset + PIIX4_FUNC3IO_PMCNTRL); > > /* If the special cycle occurs too soon this doesn't work... */ > - mdelay(10); > + usleep_range(10000, 11000); > > /* > * The PIIX4 will enter the suspend state only after seeing a special > @@ -59,7 +59,7 @@ static void piix4_poweroff(void) > PIIX4_SUSPEND_MAGIC); > > /* Give the system some time to power down, then error */ > - mdelay(1000); > + msleep(1000); > pr_emerg("Unable to poweroff system\n"); > } > > -- > 2.17.0 > [unhandled content-type:application/pgp-signature] | |