From: Alexandre Belloni <alexandre.belloni@bootlin.com>
To: Rob Herring <robh@kernel.org>
Cc: "Sam Ravnborg" <sam@ravnborg.org>,
"Alessandro Zummo" <a.zummo@towertech.it>,
"Andrew Jeffery" <andrew@aj.id.au>,
"Fabio Estevam" <fabio.estevam@nxp.com>,
"Joel Stanley" <joel@jms.id.au>,
"Mark Rutland" <mark.rutland@arm.com>,
"Russell King" <linux@armlinux.org.uk>,
"Sascha Hauer" <s.hauer@pengutronix.de>,
"Shawn Guo" <shawnguo@kernel.org>,
devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-rtc@vger.kernel.org, "Søren Andersen" <san@skov.dk>
Subject: Re: [PATCH v1 1/5] dt-binding: rtci-pcf8523: add quartz_load property
Date: Wed, 26 Sep 2018 20:51:21 +0200 [thread overview]
Message-ID: <20180926185121.GF16644@piout.net> (raw)
In-Reply-To: <20180926154708.GA3264@bogus>
On 26/09/2018 10:47:08-0500, Rob Herring wrote:
> > > +Optional property:
> > > +- nxp,quartz_load_12.5pF: The capacitive load on the quartz is 12.5 pF,
> > > + which differ from the default value of 7 pF
> > > +
> >
> > The boolean properties usually don't work well for RTCs because people
> > usually want to keep any previous configuration that may have been done
> > at the factory or in the bootloader so I would use:
> >
> > nxp,quartz_load_fF and this would be either 7000 or 12500.
>
> Use '-' rather than '_'.
>
> There's already a defined unit suffix of '-picofarads'. If you need
> '-femtofarads', then please add to property-units.txt. Though I'd prefer
> not as wouldn't a value of 12 (or 13) be close enough for the needs
> here?
>
For that particular RTC, yes but the isl1208 has 0.5pF steps and the
x1205 has 0.25pf steps. I'd prefer having a single generic property for
all the RTCs: quartz-load-femtofarads.
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
next prev parent reply other threads:[~2018-09-27 1:05 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20180822183555.GA24084@ravnborg.org>
2018-09-07 19:35 ` [PATCH v1 0/5] add quartz load support to NXP rtc drivers Sam Ravnborg
2018-09-07 19:35 ` [PATCH v1 1/5] dt-binding: rtci-pcf8523: add quartz_load property Sam Ravnborg
2018-09-07 21:43 ` Sam Ravnborg
2018-09-13 19:05 ` Alexandre Belloni
2018-09-13 20:44 ` Sam Ravnborg
2018-09-13 20:51 ` Alexandre Belloni
2018-09-26 15:47 ` Rob Herring
2018-09-26 18:51 ` Alexandre Belloni [this message]
2018-09-26 20:42 ` Sam Ravnborg
2018-09-07 19:35 ` [PATCH v1 2/5] dt-binding: rtc-pcf85063: add quartz load property Sam Ravnborg
2018-09-13 19:11 ` Alexandre Belloni
2018-09-07 19:35 ` [PATCH v1 3/5] dts: add nxp,quartz_load_12.5pf to all pcf8523 nodes Sam Ravnborg
2018-09-13 19:14 ` Alexandre Belloni
2018-09-07 19:35 ` [PATCH v1 4/5] rtc: pcf8523: external capacitor configuration Sam Ravnborg
2018-09-13 19:27 ` Alexandre Belloni
2018-09-07 19:35 ` [PATCH v1 5/5] rtc: pcf85063: " Sam Ravnborg
2018-09-13 19:29 ` Alexandre Belloni
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180926185121.GF16644@piout.net \
--to=alexandre.belloni@bootlin.com \
--cc=a.zummo@towertech.it \
--cc=andrew@aj.id.au \
--cc=devicetree@vger.kernel.org \
--cc=fabio.estevam@nxp.com \
--cc=joel@jms.id.au \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rtc@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=mark.rutland@arm.com \
--cc=robh@kernel.org \
--cc=s.hauer@pengutronix.de \
--cc=sam@ravnborg.org \
--cc=san@skov.dk \
--cc=shawnguo@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).