1 /* 2 * Chromium OS Matrix Keyboard Message Protocol definitions 3 * 4 * Copyright (c) 2012 The Chromium OS Authors. 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #ifndef _CROS_MESSAGE_H 10 #define _CROS_MESSAGE_H 11 12 /* 13 * Command interface between EC and AP, for LPC, I2C and SPI interfaces. 14 * 15 * This is copied from the Chromium OS Open Source Embedded Controller code. 16 */ 17 enum { 18 /* The header byte, which follows the preamble */ 19 MSG_HEADER = 0xec, 20 21 MSG_HEADER_BYTES = 3, 22 MSG_TRAILER_BYTES = 2, 23 MSG_PROTO_BYTES = MSG_HEADER_BYTES + MSG_TRAILER_BYTES, 24 25 /* Max length of messages */ 26 MSG_BYTES = EC_HOST_PARAM_SIZE + MSG_PROTO_BYTES, 27 }; 28 29 #endif 30