From: Kevin Hilman Date: Mon, 12 Aug 2019 23:28:49 +0000 (-0700) Subject: dt-bindings: rtc: new binding for Amlogic VRTC X-Git-Tag: v5.4-rc1~74^2~26 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ed16239637f6656d3e6656ed1753e70d7823d94f;p=thirdparty%2Flinux.git dt-bindings: rtc: new binding for Amlogic VRTC Add binding fo the new VRTC driver for Amlogic SoCs. The 64-bit family of SoCs only has an RTC managed by firmware, and this VRTC driver provides the simple, one-register firmware interface. Reviewed-by: Rob Herring Signed-off-by: Kevin Hilman Link: https://lore.kernel.org/r/20190812232850.8016-2-khilman@kernel.org Signed-off-by: Alexandre Belloni --- diff --git a/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt b/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt new file mode 100644 index 0000000000000..c014f54a98530 --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt @@ -0,0 +1,22 @@ +* Amlogic Virtual RTC (VRTC) + +This is a Linux interface to an RTC managed by firmware, hence it's +virtual from a Linux perspective. The interface is 1 register where +an alarm time (in seconds) is to be written. + +Required properties: +- compatible: should be "amlogic,meson-vrtc" +- reg: physical address for the alarm register + +The alarm register is a simple scratch register shared between the +application processors (AP) and the secure co-processor (SCP.) When +the AP suspends, the SCP will use the value of this register to +program an always-on timer before going sleep. When the timer expires, +the SCP will wake up and will then wake the AP. + +Example: + + vrtc: rtc@0a8 { + compatible = "amlogic,meson-vrtc"; + reg = <0x0 0x000a8 0x0 0x4>; + };