From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH 1/3] dt-bindings: mfd: Document the RTC present on MAX77620 Date: Thu, 30 Apr 2020 09:07:01 -0500 Message-ID: <20200430140701.GA21776@bogus> References: <20200417170825.2551367-1-thierry.reding@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20200417170825.2551367-1-thierry.reding@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Thierry Reding Cc: Lee Jones , Alessandro Zummo , Alexandre Belloni , Jon Hunter , devicetree@vger.kernel.org, linux-rtc@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org On Fri, Apr 17, 2020 at 07:08:23PM +0200, Thierry Reding wrote: > From: Thierry Reding > > The RTC present on MAX77620 can be used to generate an alarm at a given > time, which in turn can be used as a wakeup source for the system if it > is properly wired up. > > Document how to enable the RTC to act as a wakeup source. > > Signed-off-by: Thierry Reding > --- > .../devicetree/bindings/mfd/max77620.txt | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mfd/max77620.txt b/Documentation/devicetree/bindings/mfd/max77620.txt > index 5a642a51d58e..f05005b0993e 100644 > --- a/Documentation/devicetree/bindings/mfd/max77620.txt > +++ b/Documentation/devicetree/bindings/mfd/max77620.txt > @@ -125,6 +125,17 @@ MAX77663 supports 20, 40, 80, 160, 320, 640, 1280 and 2540 microseconds. > control) then, GPIO1/nRST_IO goes LOW. > this property is valid for max20024 only. > > +Realtime Clock > +-------------- > +The MAX77620 family of power management ICs contain a realtime clock block > +that can be used to keep track of time even when the system is powered off. > + > +The realtime clock can also be programmed to trigger alerts, which can be > +used to wake the system up from sleep. In order to configure the RTC to act > +as a wakeup source, add an "rtc" child node and add the "wakeup-source" > +property. > + > + > For DT binding details of different sub modules like GPIO, pincontrol, > regulator, power, please refer respective device-tree binding document > under their respective sub-system directories. > @@ -159,4 +170,8 @@ max77620@3c { > maxim,fps-event-source = ; > }; > }; > + > + rtc { > + wakeup-source; Is the RTC really the only thing that could wake the system in this PMIC? I don't think it's really valid to have 'wakeup-source' without 'interrupts' unless the wakeup mechanism is somehow not an interrupt. So I think this belongs in the parent node. Rob