From: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
To: Rob Herring <robh+dt@kernel.org>
Cc: "open list:REAL TIME CLOCK (RTC) SUBSYSTEM"
<linux-rtc@vger.kernel.org>,
"Alexandre Belloni" <alexandre.belloni@bootlin.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>,
"Qiang Zhao" <qiang.zhao@nxp.com>,
"Bruno Thomsen" <bruno.thomsen@gmail.com>
Subject: Re: [PATCH v2 1/3] dt-bindings: rtc: add reset-source property
Date: Sat, 12 Dec 2020 00:10:11 +0100 [thread overview]
Message-ID: <b3c05d29-3ed6-d5f5-d1dd-0ddec1f89276@prevas.dk> (raw)
In-Reply-To: <CAL_JsqJ-5gwycTRQCdX=ZsefEJ=F1GyTjjDW6QB1PBynibFzLg@mail.gmail.com>
On 11/12/2020 23.30, Rob Herring wrote:
> On Fri, Dec 11, 2020 at 3:56 PM Rasmus Villemoes
> <rasmus.villemoes@prevas.dk> wrote:
>>
>> Some RTCs, e.g. the pcf2127, can be used as a hardware watchdog. But
>> if the reset pin is not actually wired up, the driver exposes a
>> watchdog device that doesn't actually work.
>>
>> Provide a standard binding that can be used to indicate that a given
>> RTC can perform a reset of the machine, similar to wakeup-source.
>
> Why not use the watchdog 'timeout-sec' property?
Wouldn't that be overloading that property? AFAIU, that is used to ask
the kernel to program an initial timeout value into the watchdog device.
But what if one doesn't want to start the watchdog device at kernel
boot, but just indicate that the RTC has that capability?
It's quite possible that if it can act as a watchdog device (and
has-watchdog was also suggested), one would also want timeout-sec and
other watchdog bindings to apply. But that can be added later, by those
who actually want that.
For now, I'd really like to get my board booting again (or rather, not
get reset by the real watchdog just because the pcf2127 driver now
exposes something as /dev/wathdog0, pushing the real one to
/dev/wathcdog1 which doesn't get pinged from userspace).
Rasmus
next prev parent reply other threads:[~2020-12-11 23:44 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-21 5:48 [Patch v2 1/3] dt-bindings: rtc: pcf2127: Add bindings for nxp,pcf2127 Qiang Zhao
2020-09-21 5:48 ` [Patch v2 2/3] rtc: pcf2127: add "no-watchdog" property Qiang Zhao
2020-09-21 5:48 ` [Patch v2 3/3] arm64: dts: lx2160a: Add "no-watchdog" property to pcf2127 Qiang Zhao
2020-09-23 9:44 ` [Patch v2 1/3] dt-bindings: rtc: pcf2127: Add bindings for nxp,pcf2127 Alexandre Belloni
2020-09-24 3:20 ` Qiang Zhao
2020-09-24 7:04 ` Uwe Kleine-König
2020-09-24 7:23 ` Qiang Zhao
2020-09-24 7:47 ` Alexandre Belloni
2020-09-24 10:52 ` [PATCH 0/2] rtc: pcf2127: only use watchdog when explicitly available Uwe Kleine-König
2020-09-24 10:52 ` [PATCH 1/2] rtc: pcf2127: move watchdog initialisation to a separate function Uwe Kleine-König
2020-09-27 7:50 ` Bruno Thomsen
2020-09-24 10:52 ` [PATCH 2/2] [RFC] rtc: pcf2127: only use watchdog when explicitly available Uwe Kleine-König
2020-09-27 8:09 ` Bruno Thomsen
2020-09-27 15:54 ` Guenter Roeck
2020-09-28 8:43 ` Uwe Kleine-König
2020-09-28 16:26 ` Guenter Roeck
2020-10-26 7:23 ` [PATCH 0/2] " Qiang Zhao
2020-10-26 20:48 ` Alexandre Belloni
2020-10-26 21:29 ` Guenter Roeck
2020-11-30 9:51 ` Rasmus Villemoes
2020-12-04 9:27 ` Alexandre Belloni
2020-12-11 21:56 ` [PATCH v2 0/3] add reset-source RTC binding, update pcf2127 driver Rasmus Villemoes
2020-12-11 21:56 ` [PATCH v2 1/3] dt-bindings: rtc: add reset-source property Rasmus Villemoes
2020-12-11 22:30 ` Rob Herring
2020-12-11 23:10 ` Rasmus Villemoes [this message]
2020-12-17 16:51 ` Rob Herring
2020-12-17 18:12 ` Uwe Kleine-König
2020-12-17 18:23 ` Rasmus Villemoes
2020-12-17 19:02 ` Rob Herring
2020-12-17 20:28 ` Uwe Kleine-König
2020-12-12 9:25 ` Uwe Kleine-König
2020-12-11 21:56 ` [PATCH v2 2/3] rtc: pcf2127: move watchdog initialisation to a separate function Rasmus Villemoes
2020-12-11 21:56 ` [PATCH v2 3/3] rtc: pcf2127: only use watchdog when explicitly available Rasmus Villemoes
2020-12-18 10:10 ` [PATCH v3 0/2] add reset-source RTC binding, update pcf2127 driver Rasmus Villemoes
2020-12-18 10:10 ` [PATCH v3 1/2] dt-bindings: rtc: add reset-source property Rasmus Villemoes
2020-12-18 21:19 ` Rob Herring
2020-12-18 10:10 ` [PATCH v3 2/2] rtc: pcf2127: only use watchdog when explicitly available Rasmus Villemoes
2020-12-19 0:58 ` [PATCH v3 0/2] add reset-source RTC binding, update pcf2127 driver Alexandre Belloni
2020-09-24 16:59 ` [Patch v2 1/3] dt-bindings: rtc: pcf2127: Add bindings for nxp,pcf2127 Bruno Thomsen
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