From: Alexandre Belloni <alexandre.belloni@bootlin.com>
To: Sam Ravnborg <sam@ravnborg.org>
Cc: "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>,
"Rob Herring" <robh+dt@kernel.org>,
"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 5/5] rtc: pcf85063: external capacitor configuration
Date: Thu, 13 Sep 2018 21:29:24 +0200 [thread overview]
Message-ID: <20180913192924.GK14988@piout.net> (raw)
In-Reply-To: <20180907193508.24974-6-sam@ravnborg.org>
On 07/09/2018 21:35:08+0200, Sam Ravnborg wrote:
> From: Søren Andersen <san@skov.dk>
>
> Add support for specifying the quartz load in the DT node.
> The pcf85063 may use either a 7 pF or an 12.5 pF xtal.
> If the rtc has the wrong configuration the time will
> drift several hours/week.
>
> If nothing is specified in DT then the factory default of 7 pF is used.
>
> Signed-off-by: Søren Andersen <san@skov.dk>
> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
> Cc: Alessandro Zummo <a.zummo@towertech.it>
> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
> ---
> drivers/rtc/rtc-pcf85063.c | 31 +++++++++++++++++++++++++++++++
> 1 file changed, 31 insertions(+)
>
> diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c
> index 283c2335b01b..38163446664f 100644
> --- a/drivers/rtc/rtc-pcf85063.c
> +++ b/drivers/rtc/rtc-pcf85063.c
> @@ -27,6 +27,7 @@
> */
>
> #define PCF85063_REG_CTRL1 0x00 /* status */
> +#define PCF85063_REG_CTRL1_CAP_SEL BIT(0)
> #define PCF85063_REG_CTRL1_STOP BIT(5)
> #define PCF85063_REG_CTRL2 0x01
>
> @@ -180,6 +181,31 @@ static const struct rtc_class_ops pcf85063_rtc_ops = {
> .set_time = pcf85063_rtc_set_time
> };
>
> +static int pcf85063_select_capacitance(struct i2c_client *client)
> +{
> + int rc;
> + u8 reg;
> +
> + rc = i2c_smbus_read_byte_data(client, PCF85063_REG_CTRL1);
> + if (rc < 0) {
> + dev_err(&client->dev, "Failing to read Control1 reg\n");
> + return -EIO;
> + }
> +
> + if (device_property_present(&client->dev, "nxp,quartz_load_12.5pf"))
> + reg = rc |= PCF85063_REG_CTRL1_CAP_SEL;
> + else
> + reg = rc &= ~PCF85063_REG_CTRL1_CAP_SEL;
That one is more straight forward, set it to the value from DT or leave
it alone.
--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
prev parent reply other threads:[~2018-09-13 19:29 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
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 [this message]
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=20180913192924.GK14988@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+dt@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).