From 20e6cf7e747815461ac8bcb526f7079ce48866b5 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marek=20Beh=C3=BAn?= Date: Mon, 12 Aug 2019 18:11:15 +0200 Subject: dt-bindings: bus: Document moxtet bus binding MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds device tree binding documentation for the Moxtet bus, a bus via which the different modules connected to the Turris Mox router can be configured. Link: https://lore.kernel.org/r/20190812161118.21476-3-marek.behun@nic.cz Signed-off-by: Marek Behún Reviewed-by: Rob Herring Signed-off-by: Arnd Bergmann --- Documentation/devicetree/bindings/bus/moxtet.txt | 46 ++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/devicetree/bindings/bus/moxtet.txt (limited to 'Documentation/devicetree/bindings/bus') diff --git a/Documentation/devicetree/bindings/bus/moxtet.txt b/Documentation/devicetree/bindings/bus/moxtet.txt new file mode 100644 index 000000000000..fb50fc865336 --- /dev/null +++ b/Documentation/devicetree/bindings/bus/moxtet.txt @@ -0,0 +1,46 @@ +Turris Mox module status and configuration bus (over SPI) + +Required properties: + - compatible : Should be "cznic,moxtet" + - #address-cells : Has to be 1 + - #size-cells : Has to be 0 + - spi-cpol : Required inverted clock polarity + - spi-cpha : Required shifted clock phase + - interrupts : Must contain reference to the shared interrupt line + - interrupt-controller : Required + - #interrupt-cells : Has to be 1 + +For other required and optional properties of SPI slave nodes please refer to +../spi/spi-bus.txt. + +Required properties of subnodes: + - reg : Should be position on the Moxtet bus (how many Moxtet + modules are between this module and CPU module, so + either 0 or a positive integer) + +The driver finds the devices connected to the bus by itself, but it may be +needed to reference some of them from other parts of the device tree. In that +case the devices can be defined as subnodes of the moxtet node. + +Example: + + moxtet@1 { + compatible = "cznic,moxtet"; + #address-cells = <1>; + #size-cells = <0>; + reg = <1>; + spi-max-frequency = <10000000>; + spi-cpol; + spi-cpha; + interrupt-controller; + #interrupt-cells = <1>; + interrupt-parent = <&gpiosb>; + interrupts = <5 IRQ_TYPE_EDGE_FALLING>; + + moxtet_sfp: gpio@0 { + compatible = "cznic,moxtet-gpio"; + gpio-controller; + #gpio-cells = <2>; + reg = <0>; + } + }; -- cgit v1.2.3