From: Søren Andersen <s...@skov.dk>
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 <s...@skov.dk>
Signed-off-by: Sam Ravnborg <s...@ravnborg.org>
Cc: Alessandro Zummo <a.zu...@towertech.it>
Cc: Alexandre Belloni <alexandre.bell...@bootlin.com>
Cc: Rob Herring <robh...@kernel.org>
Cc: Mark Rutland <mark.rutl...@arm.com>
---
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
