spi-nor: Add support for Intel SPI serial flash controller

Add support for the SPI serial flash host controller found on many Intel
CPUs including Baytrail and Braswell. The SPI serial flash controller is
used to access BIOS and other platform specific information. By default the
driver exposes a single read-only MTD device but with a module parameter
"writeable=1" the MTD device can be made read-write which makes it possible
to upgrade BIOS directly from Linux.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

include/linux/platform_data/intel-spi.h

@@ -0,0 +1,31 @@
+/*
+ * Intel PCH/PCU SPI flash driver.
+ *
+ * Copyright (C) 2016, Intel Corporation
+ * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef INTEL_SPI_PDATA_H
+#define INTEL_SPI_PDATA_H
+
+enum intel_spi_type {
+	INTEL_SPI_BYT = 1,
+	INTEL_SPI_LPT,
+	INTEL_SPI_BXT,
+};
+
+/**
+ * struct intel_spi_boardinfo - Board specific data for Intel SPI driver
+ * @type: Type which this controller is compatible with
+ * @writeable: The chip is writeable
+ */
+struct intel_spi_boardinfo {
+	enum intel_spi_type type;
+	bool writeable;
+};
+
+#endif /* INTEL_SPI_PDATA_H */