Re: [PATCH] mfd: axp20x: Do not sleep in the power off handler

From: Lee Jones
Date: Mon Nov 14 2022 - 06:03:17 EST


On Mon, 07 Nov 2022, Dmitry Osipenko wrote:

> On 11/7/22 12:39, Lee Jones wrote:
> > On Mon, 07 Nov 2022, Dmitry Osipenko wrote:
> >
> >> On 11/6/22 00:29, Samuel Holland wrote:
> >>> Since commit 856c288b0039 ("ARM: Use do_kernel_power_off()"), the
> >>> function axp20x_power_off() now runs inside a RCU read-side critical
> >>> section, so it is not allowed to call msleep(). Use mdelay() instead.
> >>>
> >>> Fixes: 856c288b0039 ("ARM: Use do_kernel_power_off()")
> >>> Signed-off-by: Samuel Holland <samuel@xxxxxxxxxxxx>
> >>> ---
> >>>
> >>> drivers/mfd/axp20x.c | 2 +-
> >>> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
> >>> index 88a212a8168c..880c41fa7021 100644
> >>> --- a/drivers/mfd/axp20x.c
> >>> +++ b/drivers/mfd/axp20x.c
> >>> @@ -842,7 +842,7 @@ static void axp20x_power_off(void)
> >>> AXP20X_OFF);
> >>>
> >>> /* Give capacitors etc. time to drain to avoid kernel panic msg. */
> >>> - msleep(500);
> >>> + mdelay(500);
> >>> }
> >>>
> >>> int axp20x_match_device(struct axp20x_dev *axp20x)
> >>
> >> ARM was doing local_irq_disable() on power-off before
> >> do_kernel_power_off() was introduced, so this should've been incorrect
> >> for a couple years at least. If I'm not missing anything.
> >
> > Is that a review? Care to provide a tag?
>
> It's a review and my point was that the "Fixes" tag in this patch
> doesn't look correct. But this is minor comment, otherwise patch looks
> okay. Hope that the relevant I2C controller driver supports atomic
> transfer that are required for power-off to work.
>
> Reviewed-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>

Thanks.

--
Lee Jones [李琼斯]