| Message ID | 20190119090031.29147-5-sam@ravnborg.org |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | add quartz load support to NXP rtc drivers | expand |
| Context | Check | Description |
|---|---|---|
| robh/checkpatch | success |
On Sat, 19 Jan 2019 10:00:29 +0100, Sam Ravnborg wrote: > The NXP pcf85063 supports two different xtal load capacitance > - 7000fF (7pF) HW default, Linux driver default > - 12500fF (12.5pF) Minimum power consumption > > To obtain a precise RTC the pcf85063 must be configured > with the correct capacitance load of the xtal. > > Add a property to specify the xtal capacitance load. > The default value matches that of the current Linux driver. > > With a dedicated binding remove the entry in rtc.txt > > 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> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Urs Fässler <urs.fassler@bbv.ch> > --- > Documentation/devicetree/bindings/rtc/nxp,pcf85063.txt | 18 ++++++++++++++++++ > Documentation/devicetree/bindings/rtc/rtc.txt | 1 - > 2 files changed, 18 insertions(+), 1 deletion(-) > create mode 100644 Documentation/devicetree/bindings/rtc/nxp,pcf85063.txt > Reviewed-by: Rob Herring <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/rtc/nxp,pcf85063.txt b/Documentation/devicetree/bindings/rtc/nxp,pcf85063.txt new file mode 100644 index 000000000000..d3e380ad712d --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/nxp,pcf85063.txt @@ -0,0 +1,18 @@ +* NXP PCF85063 Real Time Clock + +Required properties: +- compatible: Should contain "nxp,pcf85063". +- reg: I2C address for chip. + +Optional property: +- quartz-load-femtofarads: The capacitive load of the quartz(x-tal), + expressed in femto Farad (fF). Valid values are 7000 and 12500. + Default value (if no value is specified) is 7000fF. + +Example: + +pcf85063: rtc@51 { + compatible = "nxp,pcf85063"; + reg = <0x51>; + quartz-load-femtofarads = <12500>; +}; diff --git a/Documentation/devicetree/bindings/rtc/rtc.txt b/Documentation/devicetree/bindings/rtc/rtc.txt index 6d726a801d21..460c503e86c6 100644 --- a/Documentation/devicetree/bindings/rtc/rtc.txt +++ b/Documentation/devicetree/bindings/rtc/rtc.txt @@ -56,7 +56,6 @@ microcrystal,rv3029 Real Time Clock Module with I2C-Bus nxp,pcf2127 Real-time clock nxp,pcf2129 Real-time clock nxp,pcf8563 Real-time clock/calendar -nxp,pcf85063 Tiny Real-Time Clock pericom,pt7c4338 Real-time Clock Module ricoh,r2025sd I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC ricoh,r2221tl I2C bus SERIAL INTERFACE REAL-TIME CLOCK IC