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 <bhthompson@chromium.org>
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Signed-off-by: Hung-ying Tyan <tyanh@chromium.org>
Signed-off-by: Louis Yung-Chieh Lo <yjlou@chromium.org>
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

include/cros_ec_message.h

@@ -0,0 +1,44 @@
+/*
+ * Chromium OS Matrix Keyboard Message Protocol definitions
+ *
+ * Copyright (c) 2012 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _CROS_MESSAGE_H
+#define _CROS_MESSAGE_H
+
+/*
+ * Command interface between EC and AP, for LPC, I2C and SPI interfaces.
+ *
+ * This is copied from the Chromium OS Open Source Embedded Controller code.
+ */
+enum {
+	/* The header byte, which follows the preamble */
+	MSG_HEADER	= 0xec,
+
+	MSG_HEADER_BYTES	= 3,
+	MSG_TRAILER_BYTES	= 2,
+	MSG_PROTO_BYTES		= MSG_HEADER_BYTES + MSG_TRAILER_BYTES,
+
+	/* Max length of messages */
+	MSG_BYTES		= EC_HOST_PARAM_SIZE + MSG_PROTO_BYTES,
+};
+
+#endif