Add support for the ENE Embedded Debug Interface EDI and KB9012 EC

The ENE Embedded Debug Interface (EDI) is a SPI-based interface for
accessing the memory of ENE embedded controllers.

The ENE KB9012 EC is an embedded controller found on various laptops
such as the Lenovo G505s. It features a 8051 microcontroller and
has 128 KiB of internal storage for program data.

EDI can be accessed on the KB9012 through pins 59-62 (CS-CLK-MOSI-MISO)
when flash direct access is not in use. Some firmwares disable EDI at runtime
so it might be necessary to ground pin 42 to reset the 8051 microcontroller
before accessing the KB9012 via EDI.

The example of flashing KB9012 at Lenovo G505S laptop could be found here:
http://dangerousprototypes.com/docs/Flashing_KB9012_with_Bus_Pirate

Change-Id: Ib8b2eb2feeef5c337d725d15ebf994a299897854
Signed-off-by: Mike Banon <mikebdp2@gmail.com>
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Reviewed-on: https://review.coreboot.org/23259
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/edi.h b/edi.h
new file mode 100644
index 0000000..542bf26
--- /dev/null
+++ b/edi.h
@@ -0,0 +1,30 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2015 Paul Kocialkowski <contact@paulk.fr>
+ *
+ * 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.
+ */
+
+#ifndef __EDI_H__
+#define __EDI_H__ 1
+
+#define EDI_READ			0x30
+#define EDI_WRITE			0x40
+#define EDI_DISABLE			0xf3
+
+#define EDI_NOT_READY			0x5f
+#define EDI_READY			0x50
+
+#define EDI_READ_BUFFER_LENGTH_DEFAULT	3
+#define EDI_READ_BUFFER_LENGTH_MAX	32
+
+#endif