From 88364387c60dc72549ccf7f2d595cbf847ab4e17 Mon Sep 17 00:00:00 2001 From: Hung-ying Tyan Date: Wed, 15 May 2013 18:27:28 +0800 Subject: cros: add cros_ec driver This patch adds the cros_ec driver that implements the protocol for communicating with Google's ChromeOS embedded controller. Signed-off-by: Bernie Thompson Signed-off-by: Bill Richardson Signed-off-by: Che-Liang Chiou Signed-off-by: Doug Anderson Signed-off-by: Gabe Black Signed-off-by: Hung-ying Tyan Signed-off-by: Louis Yung-Chieh Lo Signed-off-by: Randall Spangler Signed-off-by: Sean Paul Signed-off-by: Simon Glass Signed-off-by: Vincent Palatin Acked-by: Simon Glass Tested-by: Simon Glass --- doc/device-tree-bindings/misc/cros-ec.txt | 38 +++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 doc/device-tree-bindings/misc/cros-ec.txt (limited to 'doc/device-tree-bindings') diff --git a/doc/device-tree-bindings/misc/cros-ec.txt b/doc/device-tree-bindings/misc/cros-ec.txt new file mode 100644 index 0000000000..07ea7cdeac --- /dev/null +++ b/doc/device-tree-bindings/misc/cros-ec.txt @@ -0,0 +1,38 @@ +Chrome OS CROS_EC Binding +====================== + +The device tree node which describes the operation of the CROS_EC interface +is as follows: + +Required properties : +- compatible = "google,cros-ec" + +Optional properties : +- spi-max-frequency : Sets the maximum frequency (in Hz) for SPI bus + operation +- i2c-max-frequency : Sets the maximum frequency (in Hz) for I2C bus + operation +- ec-interrupt : Selects the EC interrupt, defined as a GPIO according + to the platform +- optimise-flash-write : Boolean property - if present then flash blocks + containing all 0xff will not be written, since we assume that the EC + uses that pattern for erased blocks + +The CROS_EC node should appear as a subnode of the interrupt that connects it +to the EC (e.g. i2c, spi, lpc). The reg property (as usual) will indicate +the unit address on that bus. + + +Example +======= + + spi@131b0000 { + cros-ec@0 { + reg = <0>; + compatible = "google,cros-ec"; + spi-max-frequency = <5000000>; + ec-interrupt = <&gpio 174 1>; + optimise-flash-write; + status = "disabled"; + }; + }; -- cgit v1.2.1