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* [PATCH v3] rtc: wilco-ec: Handle reading invalid times
@ 2019-09-25 20:32 Nick Crews
  2019-09-25 20:51 ` Dmitry Torokhov
  2019-10-01 19:53 ` Alexandre Belloni
  0 siblings, 2 replies; 8+ messages in thread
From: Nick Crews @ 2019-09-25 20:32 UTC (permalink / raw)
  To: Alexandre Belloni, Alessandro Zummo
  Cc: linux-rtc, linux-kernel, Pavel Machek, enric.balletbo, bleung,
	dlaurie, djkurtz, dtor, Nick Crews

If the RTC HW returns an invalid time, the rtc_year_days()
call would crash. This patch adds error logging in this
situation, and removes the tm_yday and tm_wday calculations.
These fields should not be relied upon by userspace
according to man rtc, and thus we don't need to calculate
them.

Signed-off-by: Nick Crews <ncrews@chromium.org>
---
 drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
index 8ad4c4e6d557..53da355d996a 100644
--- a/drivers/rtc/rtc-wilco-ec.c
+++ b/drivers/rtc/rtc-wilco-ec.c
@@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
 	tm->tm_mday	= rtc.day;
 	tm->tm_mon	= rtc.month - 1;
 	tm->tm_year	= rtc.year + (rtc.century * 100) - 1900;
-	tm->tm_yday	= rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
-
-	/* Don't compute day of week, we don't need it. */
-	tm->tm_wday = -1;
+	/* Ignore other tm fields, man rtc says userspace shouldn't use them. */
+
+	if (rtc_valid_tm(tm)) {
+		dev_err(dev,
+			 "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
+			 rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
+			 rtc.year, rtc.century);
+		return -EIO;
+	}
 
 	return 0;
 }
-- 
2.21.0


^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-09-25 20:32 [PATCH v3] rtc: wilco-ec: Handle reading invalid times Nick Crews
@ 2019-09-25 20:51 ` Dmitry Torokhov
  2019-10-01 19:53 ` Alexandre Belloni
  1 sibling, 0 replies; 8+ messages in thread
From: Dmitry Torokhov @ 2019-09-25 20:51 UTC (permalink / raw)
  To: Nick Crews
  Cc: Alexandre Belloni, Alessandro Zummo, linux-rtc, lkml,
	Pavel Machek, enric.balletbo, Benson Leung, dlaurie,
	Daniel Kurtz

On Wed, Sep 25, 2019 at 1:32 PM Nick Crews <ncrews@chromium.org> wrote:
>
> If the RTC HW returns an invalid time, the rtc_year_days()
> call would crash. This patch adds error logging in this
> situation, and removes the tm_yday and tm_wday calculations.
> These fields should not be relied upon by userspace
> according to man rtc, and thus we don't need to calculate
> them.
>
> Signed-off-by: Nick Crews <ncrews@chromium.org>

Reviewed-by: Dmitry Torokhov <dtor@chromium.org>

> ---
>  drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
> index 8ad4c4e6d557..53da355d996a 100644
> --- a/drivers/rtc/rtc-wilco-ec.c
> +++ b/drivers/rtc/rtc-wilco-ec.c
> @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
>         tm->tm_mday     = rtc.day;
>         tm->tm_mon      = rtc.month - 1;
>         tm->tm_year     = rtc.year + (rtc.century * 100) - 1900;
> -       tm->tm_yday     = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
> -
> -       /* Don't compute day of week, we don't need it. */
> -       tm->tm_wday = -1;
> +       /* Ignore other tm fields, man rtc says userspace shouldn't use them. */
> +
> +       if (rtc_valid_tm(tm)) {
> +               dev_err(dev,
> +                        "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
> +                        rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
> +                        rtc.year, rtc.century);
> +               return -EIO;
> +       }
>
>         return 0;
>  }
> --
> 2.21.0
>

Thanks.

-- 
Dmitry

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-09-25 20:32 [PATCH v3] rtc: wilco-ec: Handle reading invalid times Nick Crews
  2019-09-25 20:51 ` Dmitry Torokhov
@ 2019-10-01 19:53 ` Alexandre Belloni
  2019-10-01 20:42   ` Dmitry Torokhov
  1 sibling, 1 reply; 8+ messages in thread
From: Alexandre Belloni @ 2019-10-01 19:53 UTC (permalink / raw)
  To: Nick Crews
  Cc: Alessandro Zummo, linux-rtc, linux-kernel, Pavel Machek,
	enric.balletbo, bleung, dlaurie, djkurtz, dtor

Hi Nick,

On 25/09/2019 14:32:09-0600, Nick Crews wrote:
> If the RTC HW returns an invalid time, the rtc_year_days()
> call would crash. This patch adds error logging in this
> situation, and removes the tm_yday and tm_wday calculations.
> These fields should not be relied upon by userspace
> according to man rtc, and thus we don't need to calculate
> them.
> 
> Signed-off-by: Nick Crews <ncrews@chromium.org>
> ---
>  drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
> index 8ad4c4e6d557..53da355d996a 100644
> --- a/drivers/rtc/rtc-wilco-ec.c
> +++ b/drivers/rtc/rtc-wilco-ec.c
> @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
>  	tm->tm_mday	= rtc.day;
>  	tm->tm_mon	= rtc.month - 1;
>  	tm->tm_year	= rtc.year + (rtc.century * 100) - 1900;
> -	tm->tm_yday	= rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
> -
> -	/* Don't compute day of week, we don't need it. */
> -	tm->tm_wday = -1;
> +	/* Ignore other tm fields, man rtc says userspace shouldn't use them. */
> +
> +	if (rtc_valid_tm(tm)) {
> +		dev_err(dev,
> +			 "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
> +			 rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
> +			 rtc.year, rtc.century);

Do you mind using %ptR? At this point you already filled the tm struct
anyway and if you print century separately, you can infer tm_year.

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-10-01 19:53 ` Alexandre Belloni
@ 2019-10-01 20:42   ` Dmitry Torokhov
  2019-10-02 10:32     ` Alexandre Belloni
  0 siblings, 1 reply; 8+ messages in thread
From: Dmitry Torokhov @ 2019-10-01 20:42 UTC (permalink / raw)
  To: Alexandre Belloni
  Cc: Nick Crews, Alessandro Zummo, linux-rtc, lkml, Pavel Machek,
	enric.balletbo, Benson Leung, dlaurie, Daniel Kurtz

On Tue, Oct 1, 2019 at 12:53 PM Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
>
> Hi Nick,
>
> On 25/09/2019 14:32:09-0600, Nick Crews wrote:
> > If the RTC HW returns an invalid time, the rtc_year_days()
> > call would crash. This patch adds error logging in this
> > situation, and removes the tm_yday and tm_wday calculations.
> > These fields should not be relied upon by userspace
> > according to man rtc, and thus we don't need to calculate
> > them.
> >
> > Signed-off-by: Nick Crews <ncrews@chromium.org>
> > ---
> >  drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
> >  1 file changed, 9 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
> > index 8ad4c4e6d557..53da355d996a 100644
> > --- a/drivers/rtc/rtc-wilco-ec.c
> > +++ b/drivers/rtc/rtc-wilco-ec.c
> > @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
> >       tm->tm_mday     = rtc.day;
> >       tm->tm_mon      = rtc.month - 1;
> >       tm->tm_year     = rtc.year + (rtc.century * 100) - 1900;
> > -     tm->tm_yday     = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
> > -
> > -     /* Don't compute day of week, we don't need it. */
> > -     tm->tm_wday = -1;
> > +     /* Ignore other tm fields, man rtc says userspace shouldn't use them. */
> > +
> > +     if (rtc_valid_tm(tm)) {
> > +             dev_err(dev,
> > +                      "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
> > +                      rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
> > +                      rtc.year, rtc.century);
>
> Do you mind using %ptR? At this point you already filled the tm struct
> anyway and if you print century separately, you can infer tm_year.

I do not think this is a good idea: we have just established that tm
does not contain valid data. Does %ptR guarantee that it handles junk
better than, let's say, rtc_year_days(), and does not crash when
presented with garbage?

Thanks,
Dmitry

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-10-01 20:42   ` Dmitry Torokhov
@ 2019-10-02 10:32     ` Alexandre Belloni
  2019-10-02 15:20       ` Dmitry Torokhov
  0 siblings, 1 reply; 8+ messages in thread
From: Alexandre Belloni @ 2019-10-02 10:32 UTC (permalink / raw)
  To: Dmitry Torokhov
  Cc: Nick Crews, Alessandro Zummo, linux-rtc, lkml, Pavel Machek,
	enric.balletbo, Benson Leung, dlaurie, Daniel Kurtz

On 01/10/2019 13:42:24-0700, Dmitry Torokhov wrote:
> On Tue, Oct 1, 2019 at 12:53 PM Alexandre Belloni
> <alexandre.belloni@bootlin.com> wrote:
> >
> > Hi Nick,
> >
> > On 25/09/2019 14:32:09-0600, Nick Crews wrote:
> > > If the RTC HW returns an invalid time, the rtc_year_days()
> > > call would crash. This patch adds error logging in this
> > > situation, and removes the tm_yday and tm_wday calculations.
> > > These fields should not be relied upon by userspace
> > > according to man rtc, and thus we don't need to calculate
> > > them.
> > >
> > > Signed-off-by: Nick Crews <ncrews@chromium.org>
> > > ---
> > >  drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
> > >  1 file changed, 9 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
> > > index 8ad4c4e6d557..53da355d996a 100644
> > > --- a/drivers/rtc/rtc-wilco-ec.c
> > > +++ b/drivers/rtc/rtc-wilco-ec.c
> > > @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
> > >       tm->tm_mday     = rtc.day;
> > >       tm->tm_mon      = rtc.month - 1;
> > >       tm->tm_year     = rtc.year + (rtc.century * 100) - 1900;
> > > -     tm->tm_yday     = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
> > > -
> > > -     /* Don't compute day of week, we don't need it. */
> > > -     tm->tm_wday = -1;
> > > +     /* Ignore other tm fields, man rtc says userspace shouldn't use them. */
> > > +
> > > +     if (rtc_valid_tm(tm)) {
> > > +             dev_err(dev,
> > > +                      "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
> > > +                      rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
> > > +                      rtc.year, rtc.century);
> >
> > Do you mind using %ptR? At this point you already filled the tm struct
> > anyway and if you print century separately, you can infer tm_year.
> 
> I do not think this is a good idea: we have just established that tm
> does not contain valid data. Does %ptR guarantee that it handles junk
> better than, let's say, rtc_year_days(), and does not crash when
> presented with garbage?
> 

It is safe to use. You can also use %ptRr if you want to ensure no
extra operations are done on the value before printing them out.

I'm still not convinced it is useful to have an error in dmesg when the
time is invalid, as long as userspace knows it is invalid. What is the
course of action for the end user when that happens?

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-10-02 10:32     ` Alexandre Belloni
@ 2019-10-02 15:20       ` Dmitry Torokhov
  2019-10-02 15:34         ` Alexandre Belloni
  2019-10-03 20:37         ` Nick Crews
  0 siblings, 2 replies; 8+ messages in thread
From: Dmitry Torokhov @ 2019-10-02 15:20 UTC (permalink / raw)
  To: Alexandre Belloni
  Cc: Nick Crews, Alessandro Zummo, linux-rtc, lkml, Pavel Machek,
	enric.balletbo, Benson Leung, dlaurie, Daniel Kurtz

On Wed, Oct 2, 2019 at 3:32 AM Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
>
> On 01/10/2019 13:42:24-0700, Dmitry Torokhov wrote:
> > On Tue, Oct 1, 2019 at 12:53 PM Alexandre Belloni
> > <alexandre.belloni@bootlin.com> wrote:
> > >
> > > Hi Nick,
> > >
> > > On 25/09/2019 14:32:09-0600, Nick Crews wrote:
> > > > If the RTC HW returns an invalid time, the rtc_year_days()
> > > > call would crash. This patch adds error logging in this
> > > > situation, and removes the tm_yday and tm_wday calculations.
> > > > These fields should not be relied upon by userspace
> > > > according to man rtc, and thus we don't need to calculate
> > > > them.
> > > >
> > > > Signed-off-by: Nick Crews <ncrews@chromium.org>
> > > > ---
> > > >  drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
> > > >  1 file changed, 9 insertions(+), 4 deletions(-)
> > > >
> > > > diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
> > > > index 8ad4c4e6d557..53da355d996a 100644
> > > > --- a/drivers/rtc/rtc-wilco-ec.c
> > > > +++ b/drivers/rtc/rtc-wilco-ec.c
> > > > @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
> > > >       tm->tm_mday     = rtc.day;
> > > >       tm->tm_mon      = rtc.month - 1;
> > > >       tm->tm_year     = rtc.year + (rtc.century * 100) - 1900;
> > > > -     tm->tm_yday     = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
> > > > -
> > > > -     /* Don't compute day of week, we don't need it. */
> > > > -     tm->tm_wday = -1;
> > > > +     /* Ignore other tm fields, man rtc says userspace shouldn't use them. */
> > > > +
> > > > +     if (rtc_valid_tm(tm)) {
> > > > +             dev_err(dev,
> > > > +                      "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
> > > > +                      rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
> > > > +                      rtc.year, rtc.century);
> > >
> > > Do you mind using %ptR? At this point you already filled the tm struct
> > > anyway and if you print century separately, you can infer tm_year.
> >
> > I do not think this is a good idea: we have just established that tm
> > does not contain valid data. Does %ptR guarantee that it handles junk
> > better than, let's say, rtc_year_days(), and does not crash when
> > presented with garbage?
> >
>
> It is safe to use. You can also use %ptRr if you want to ensure no
> extra operations are done on the value before printing them out.

OK, I'll keeo this in mind then.

>
> I'm still not convinced it is useful to have an error in dmesg when the
> time is invalid, as long as userspace knows it is invalid. What is the
> course of action for the end user when that happens?

Report it, or, in our case, we will see it in the feedback logs.
However I do agree that it is not the best option, even if we report
error to userspace I am not sure if it will handle it properly. What
userspace is supposed to do when presented with -EIO or similar?

Nick, do we know the root cause of the EC/RTC reporting invalid time?

Thanks,
Dmitry

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-10-02 15:20       ` Dmitry Torokhov
@ 2019-10-02 15:34         ` Alexandre Belloni
  2019-10-03 20:37         ` Nick Crews
  1 sibling, 0 replies; 8+ messages in thread
From: Alexandre Belloni @ 2019-10-02 15:34 UTC (permalink / raw)
  To: Dmitry Torokhov
  Cc: Nick Crews, Alessandro Zummo, linux-rtc, lkml, Pavel Machek,
	enric.balletbo, Benson Leung, dlaurie, Daniel Kurtz

On 02/10/2019 08:20:34-0700, Dmitry Torokhov wrote:
> > I'm still not convinced it is useful to have an error in dmesg when the
> > time is invalid, as long as userspace knows it is invalid. What is the
> > course of action for the end user when that happens?
> 
> Report it, or, in our case, we will see it in the feedback logs.
> However I do agree that it is not the best option, even if we report
> error to userspace I am not sure if it will handle it properly. What
> userspace is supposed to do when presented with -EIO or similar?
> 

I would say probably retry a few times if it gets -EIO and simply abort
in case of -EINVAL. I'm not aware of any userspace tool behaving that
way though. They all simply abort.

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH v3] rtc: wilco-ec: Handle reading invalid times
  2019-10-02 15:20       ` Dmitry Torokhov
  2019-10-02 15:34         ` Alexandre Belloni
@ 2019-10-03 20:37         ` Nick Crews
  1 sibling, 0 replies; 8+ messages in thread
From: Nick Crews @ 2019-10-03 20:37 UTC (permalink / raw)
  To: Dmitry Torokhov
  Cc: Alexandre Belloni, Alessandro Zummo, linux-rtc, lkml,
	Pavel Machek, Enric Balletbo i Serra, Benson Leung,
	Duncan Laurie, Daniel Kurtz

On Wed, Oct 2, 2019 at 9:20 AM Dmitry Torokhov <dtor@google.com> wrote:
>
> On Wed, Oct 2, 2019 at 3:32 AM Alexandre Belloni
> <alexandre.belloni@bootlin.com> wrote:
> >
> > On 01/10/2019 13:42:24-0700, Dmitry Torokhov wrote:
> > > On Tue, Oct 1, 2019 at 12:53 PM Alexandre Belloni
> > > <alexandre.belloni@bootlin.com> wrote:
> > > >
> > > > Hi Nick,
> > > >
> > > > On 25/09/2019 14:32:09-0600, Nick Crews wrote:
> > > > > If the RTC HW returns an invalid time, the rtc_year_days()
> > > > > call would crash. This patch adds error logging in this
> > > > > situation, and removes the tm_yday and tm_wday calculations.
> > > > > These fields should not be relied upon by userspace
> > > > > according to man rtc, and thus we don't need to calculate
> > > > > them.
> > > > >
> > > > > Signed-off-by: Nick Crews <ncrews@chromium.org>
> > > > > ---
> > > > >  drivers/rtc/rtc-wilco-ec.c | 13 +++++++++----
> > > > >  1 file changed, 9 insertions(+), 4 deletions(-)
> > > > >
> > > > > diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
> > > > > index 8ad4c4e6d557..53da355d996a 100644
> > > > > --- a/drivers/rtc/rtc-wilco-ec.c
> > > > > +++ b/drivers/rtc/rtc-wilco-ec.c
> > > > > @@ -110,10 +110,15 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
> > > > >       tm->tm_mday     = rtc.day;
> > > > >       tm->tm_mon      = rtc.month - 1;
> > > > >       tm->tm_year     = rtc.year + (rtc.century * 100) - 1900;
> > > > > -     tm->tm_yday     = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
> > > > > -
> > > > > -     /* Don't compute day of week, we don't need it. */
> > > > > -     tm->tm_wday = -1;
> > > > > +     /* Ignore other tm fields, man rtc says userspace shouldn't use them. */
> > > > > +
> > > > > +     if (rtc_valid_tm(tm)) {
> > > > > +             dev_err(dev,
> > > > > +                      "Time from RTC is invalid: second=%u, minute=%u, hour=%u, day=%u, month=%u, year=%u, century=%u",
> > > > > +                      rtc.second, rtc.minute, rtc.hour, rtc.day, rtc.month,
> > > > > +                      rtc.year, rtc.century);
> > > >
> > > > Do you mind using %ptR? At this point you already filled the tm struct
> > > > anyway and if you print century separately, you can infer tm_year.
> > >
> > > I do not think this is a good idea: we have just established that tm
> > > does not contain valid data. Does %ptR guarantee that it handles junk
> > > better than, let's say, rtc_year_days(), and does not crash when
> > > presented with garbage?
> > >
> >
> > It is safe to use. You can also use %ptRr if you want to ensure no
> > extra operations are done on the value before printing them out.
>
> OK, I'll keeo this in mind then.

I will resend this using %ptRr, chromium is using 4.19 so I didn't see
that this was added.

>
> >
> > I'm still not convinced it is useful to have an error in dmesg when the
> > time is invalid, as long as userspace knows it is invalid. What is the
> > course of action for the end user when that happens?
>
> Report it, or, in our case, we will see it in the feedback logs.
> However I do agree that it is not the best option, even if we report
> error to userspace I am not sure if it will handle it properly. What
> userspace is supposed to do when presented with -EIO or similar?

Yes, we will be able to see this in feedback logs, which would be valuable.

>
> Nick, do we know the root cause of the EC/RTC reporting invalid time?

No, I haven't really looked into it deeply. It's not limited to the RTC
interface though, it's a problem with the EC or EC communication
in general, as I've noticed similar occasional errors with the other EC
drivers.

>
> Thanks,
> Dmitry

^ permalink raw reply	[flat|nested] 8+ messages in thread

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2019-09-25 20:32 [PATCH v3] rtc: wilco-ec: Handle reading invalid times Nick Crews
2019-09-25 20:51 ` Dmitry Torokhov
2019-10-01 19:53 ` Alexandre Belloni
2019-10-01 20:42   ` Dmitry Torokhov
2019-10-02 10:32     ` Alexandre Belloni
2019-10-02 15:20       ` Dmitry Torokhov
2019-10-02 15:34         ` Alexandre Belloni
2019-10-03 20:37         ` Nick Crews

Linux-RTC Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-rtc/0 linux-rtc/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-rtc linux-rtc/ https://lore.kernel.org/linux-rtc \
		linux-rtc@vger.kernel.org linux-rtc@archiver.kernel.org
	public-inbox-index linux-rtc

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-rtc


AGPL code for this site: git clone https://public-inbox.org/ public-inbox