From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Belloni Subject: Re: [PATCH 1/2] dt-bindings: rtc: add battery-low-hw-alarm property Date: Wed, 3 Apr 2019 17:28:56 +0200 Message-ID: <20190403152856.GP22216@piout.net> References: <1554303165-24813-1-git-send-email-f.suligoi@asem.it> <20190403145709.GN22216@piout.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Flavio Suligoi Cc: Alessandro Zummo , Rob Herring , Mark Rutland , "linux-rtc@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" List-Id: devicetree@vger.kernel.org On 03/04/2019 15:06:17+0000, Flavio Suligoi wrote: > Hi Alexandre, > > > Hi, > > > > On 03/04/2019 16:52:44+0200, Flavio Suligoi wrote: > > > Some RTC devices have a battery-low automatic detection circuit. > > > The battery-low event is usually reported with: > > > > > > - a bit change in a RTC status register > > > - a hw signaling (generally using an interrupt generation), changing > > > the hw level of a specific pin; > > > > > > The new property "battery-low-hw-alarm" enable the RTC to generate the > > > hw signaling in case of battery-low event. > > > > > > Signed-off-by: Flavio Suligoi > > > --- > > > Documentation/devicetree/bindings/rtc/rtc.txt | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/Documentation/devicetree/bindings/rtc/rtc.txt > > b/Documentation/devicetree/bindings/rtc/rtc.txt > > > index a97fc6a..f93a44d 100644 > > > --- a/Documentation/devicetree/bindings/rtc/rtc.txt > > > +++ b/Documentation/devicetree/bindings/rtc/rtc.txt > > > @@ -31,6 +31,9 @@ below. > > > expressed in femto Farad (fF). > > > The default value shall be listed (if > > optional), > > > and likewise all valid values. > > > +- battery-low-hw-alarm : Enable the "battery-low" output pin. This > > function > > > > I would name that voltage-low-alarm as not all the secondary voltages > > are batteries. > > You have right. So we can also name the property a: "voltage-low-hw-alarm". > I prefer to have the word "hw" in the property name, since the "sw" voltage > low alarm is already present is some RTC drivers. > In this way, with the word "hw", is more clear that we are speaking about > an hw pin signaling. > Well, the device tree always describes the hardware so there is no point in specifying hw. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com