From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f67.google.com ([209.85.208.67]:35708 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725963AbeIHASW (ORCPT ); Fri, 7 Sep 2018 20:18:22 -0400 From: Sam Ravnborg To: Alessandro Zummo , Alexandre Belloni , Andrew Jeffery , Fabio Estevam , Joel Stanley , Mark Rutland , Rob Herring , Russell King , Sascha Hauer , Shawn Guo , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-rtc@vger.kernel.org Cc: Sam Ravnborg , =?UTF-8?q?S=C3=B8ren=20Andersen?= Subject: [PATCH v1 1/5] dt-binding: rtci-pcf8523: add quartz_load property Date: Fri, 7 Sep 2018 21:35:04 +0200 Message-Id: <20180907193508.24974-2-sam@ravnborg.org> In-Reply-To: <20180822183555.GA24084@ravnborg.org> References: <20180822183555.GA24084@ravnborg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-rtc-owner@vger.kernel.org List-ID: From: Søren Andersen The NXP pcf8523 supports two different quartz loads. - 7 pF (default) - 12.5 pF (minimum power consumption) The pcf8523 needs to know the size of the quartz load, otherwise the the RTC will have a bad precision. The default for the rtc (after power-on) is 7 pF. Add a property that tells if the external capacitor is 12.5 pF. Signed-off-by: Søren Andersen Signed-off-by: Sam Ravnborg Cc: Alessandro Zummo Cc: Alexandre Belloni Cc: Rob Herring Cc: Mark Rutland --- Documentation/devicetree/bindings/rtc/nxp,pcf8523.txt | 19 +++++++++++++++++++ Documentation/devicetree/bindings/trivial-devices.txt | 1 - 2 files changed, 19 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/rtc/nxp,pcf8523.txt diff --git a/Documentation/devicetree/bindings/rtc/nxp,pcf8523.txt b/Documentation/devicetree/bindings/rtc/nxp,pcf8523.txt new file mode 100644 index 000000000000..7c5e93f5077c --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/nxp,pcf8523.txt @@ -0,0 +1,19 @@ +* NXP PCF8523 Real Time Clock + +NXP PCF8523 Real Time Clock + +Required properties: +- compatible: Should contain "nxp,pcf8523". +- reg: I2C address for chip. + +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 + +Example: + +pcf8523: pcf8523@68 { + compatible = "nxp,pcf85063"; + reg = <0x68>; + nxp,quartz_load_12.5pF; +}; diff --git a/Documentation/devicetree/bindings/trivial-devices.txt b/Documentation/devicetree/bindings/trivial-devices.txt index 763a2808a95c..297dc82b67ad 100644 --- a/Documentation/devicetree/bindings/trivial-devices.txt +++ b/Documentation/devicetree/bindings/trivial-devices.txt @@ -169,7 +169,6 @@ nxp,pca9556 Octal SMBus and I2C registered interface nxp,pca9557 8-bit I2C-bus and SMBus I/O port with reset nxp,pcf2127 Real-time clock nxp,pcf2129 Real-time clock -nxp,pcf8523 Real-time Clock nxp,pcf8563 Real-time clock/calendar nxp,pcf85063 Tiny Real-Time Clock oki,ml86v7667 OKI ML86V7667 video decoder -- 2.12.0