mtd: spi: Port SPI NOR framework from Linux

Current U-Boot SPI NOR support (sf layer) is quite outdated as it does not
support 4 byte addressing opcodes, SFDP table parsing and different types of
quad mode enable sequences. Many newer flashes no longer support BANK
registers used by sf layer to a access >16MB of flash address space.
So, sync SPI NOR framework from Linux v4.19 that supports all the
above features. Start with basic sync up that brings in basic framework
subsequent commits will bring in more features.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Tested-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Tested-by: Stefan Roese <sr@denx.de>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> #zynq-microzed

2 files changed, 442 insertions, 0 deletions

diff --git a/include/linux/mtd/cfi.h b/include/linux/mtd/cfi.h
new file mode 100644
index 0000000000..3555518bd3
--- /dev/null
+++ b/include/linux/mtd/cfi.h
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org> et al.
+ *
+ */
+
+#ifndef __MTD_CFI_H__
+#define __MTD_CFI_H__
+
+#define CFI_MFR_ANY		0xFFFF
+#define CFI_ID_ANY		0xFFFF
+#define CFI_MFR_CONTINUATION	0x007F
+
+#define CFI_MFR_AMD		0x0001
+#define CFI_MFR_AMIC		0x0037
+#define CFI_MFR_ATMEL		0x001F
+#define CFI_MFR_EON		0x001C
+#define CFI_MFR_FUJITSU		0x0004
+#define CFI_MFR_HYUNDAI		0x00AD
+#define CFI_MFR_INTEL		0x0089
+#define CFI_MFR_MACRONIX	0x00C2
+#define CFI_MFR_NEC		0x0010
+#define CFI_MFR_PMC		0x009D
+#define CFI_MFR_SAMSUNG		0x00EC
+#define CFI_MFR_SHARP		0x00B0
+#define CFI_MFR_SST		0x00BF
+#define CFI_MFR_ST		0x0020 /* STMicroelectronics */
+#define CFI_MFR_MICRON		0x002C	/* Micron */
+#define CFI_MFR_TOSHIBA		0x0098
+#define CFI_MFR_WINBOND		0x00DA
+
+#endif /* __MTD_CFI_H__ */
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
new file mode 100644
index 0000000000..507458a760
--- /dev/null
+++ b/include/linux/mtd/spi-nor.h
@@ -0,0 +1,410 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2014 Freescale Semiconductor, Inc.
+ * Synced from Linux v4.19
+ */
+
+#ifndef __LINUX_MTD_SPI_NOR_H
+#define __LINUX_MTD_SPI_NOR_H
+
+#include <linux/bitops.h>
+#include <linux/mtd/cfi.h>
+#include <linux/mtd/mtd.h>
+
+/*
+ * Manufacturer IDs
+ *
+ * The first byte returned from the flash after sending opcode SPINOR_OP_RDID.
+ * Sometimes these are the same as CFI IDs, but sometimes they aren't.
+ */
+#define SNOR_MFR_ATMEL		CFI_MFR_ATMEL
+#define SNOR_MFR_GIGADEVICE	0xc8
+#define SNOR_MFR_INTEL		CFI_MFR_INTEL
+#define SNOR_MFR_ST		CFI_MFR_ST /* ST Micro <--> Micron */
+#define SNOR_MFR_MICRON		CFI_MFR_MICRON /* ST Micro <--> Micron */
+#define SNOR_MFR_MACRONIX	CFI_MFR_MACRONIX
+#define SNOR_MFR_SPANSION	CFI_MFR_AMD
+#define SNOR_MFR_SST		CFI_MFR_SST
+#define SNOR_MFR_WINBOND	0xef /* Also used by some Spansion */
+
+/*
+ * Note on opcode nomenclature: some opcodes have a format like
+ * SPINOR_OP_FUNCTION{4,}_x_y_z. The numbers x, y, and z stand for the number
+ * of I/O lines used for the opcode, address, and data (respectively). The
+ * FUNCTION has an optional suffix of '4', to represent an opcode which
+ * requires a 4-byte (32-bit) address.
+ */
+
+/* Flash opcodes. */
+#define SPINOR_OP_WREN		0x06	/* Write enable */
+#define SPINOR_OP_RDSR		0x05	/* Read status register */
+#define SPINOR_OP_WRSR		0x01	/* Write status register 1 byte */
+#define SPINOR_OP_RDSR2		0x3f	/* Read status register 2 */
+#define SPINOR_OP_WRSR2		0x3e	/* Write status register 2 */
+#define SPINOR_OP_READ		0x03	/* Read data bytes (low frequency) */
+#define SPINOR_OP_READ_FAST	0x0b	/* Read data bytes (high frequency) */
+#define SPINOR_OP_READ_1_1_2	0x3b	/* Read data bytes (Dual Output SPI) */
+#define SPINOR_OP_READ_1_2_2	0xbb	/* Read data bytes (Dual I/O SPI) */
+#define SPINOR_OP_READ_1_1_4	0x6b	/* Read data bytes (Quad Output SPI) */
+#define SPINOR_OP_READ_1_4_4	0xeb	/* Read data bytes (Quad I/O SPI) */
+#define SPINOR_OP_PP		0x02	/* Page program (up to 256 bytes) */
+#define SPINOR_OP_PP_1_1_4	0x32	/* Quad page program */
+#define SPINOR_OP_PP_1_4_4	0x38	/* Quad page program */
+#define SPINOR_OP_BE_4K		0x20	/* Erase 4KiB block */
+#define SPINOR_OP_BE_4K_PMC	0xd7	/* Erase 4KiB block on PMC chips */
+#define SPINOR_OP_BE_32K	0x52	/* Erase 32KiB block */
+#define SPINOR_OP_CHIP_ERASE	0xc7	/* Erase whole flash chip */
+#define SPINOR_OP_SE		0xd8	/* Sector erase (usually 64KiB) */
+#define SPINOR_OP_RDID		0x9f	/* Read JEDEC ID */
+#define SPINOR_OP_RDSFDP	0x5a	/* Read SFDP */
+#define SPINOR_OP_RDCR		0x35	/* Read configuration register */
+#define SPINOR_OP_RDFSR		0x70	/* Read flag status register */
+#define SPINOR_OP_CLFSR		0x50	/* Clear flag status register */
+#define SPINOR_OP_RDEAR		0xc8	/* Read Extended Address Register */
+#define SPINOR_OP_WREAR		0xc5	/* Write Extended Address Register */
+
+/* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
+#define SPINOR_OP_READ_4B	0x13	/* Read data bytes (low frequency) */
+#define SPINOR_OP_READ_FAST_4B	0x0c	/* Read data bytes (high frequency) */
+#define SPINOR_OP_READ_1_1_2_4B	0x3c	/* Read data bytes (Dual Output SPI) */
+#define SPINOR_OP_READ_1_2_2_4B	0xbc	/* Read data bytes (Dual I/O SPI) */
+#define SPINOR_OP_READ_1_1_4_4B	0x6c	/* Read data bytes (Quad Output SPI) */
+#define SPINOR_OP_READ_1_4_4_4B	0xec	/* Read data bytes (Quad I/O SPI) */
+#define SPINOR_OP_PP_4B		0x12	/* Page program (up to 256 bytes) */
+#define SPINOR_OP_PP_1_1_4_4B	0x34	/* Quad page program */
+#define SPINOR_OP_PP_1_4_4_4B	0x3e	/* Quad page program */
+#define SPINOR_OP_BE_4K_4B	0x21	/* Erase 4KiB block */
+#define SPINOR_OP_BE_32K_4B	0x5c	/* Erase 32KiB block */
+#define SPINOR_OP_SE_4B		0xdc	/* Sector erase (usually 64KiB) */
+
+/* Double Transfer Rate opcodes - defined in JEDEC JESD216B. */
+#define SPINOR_OP_READ_1_1_1_DTR	0x0d
+#define SPINOR_OP_READ_1_2_2_DTR	0xbd
+#define SPINOR_OP_READ_1_4_4_DTR	0xed
+
+#define SPINOR_OP_READ_1_1_1_DTR_4B	0x0e
+#define SPINOR_OP_READ_1_2_2_DTR_4B	0xbe
+#define SPINOR_OP_READ_1_4_4_DTR_4B	0xee
+
+/* Used for SST flashes only. */
+#define SPINOR_OP_BP		0x02	/* Byte program */
+#define SPINOR_OP_WRDI		0x04	/* Write disable */
+#define SPINOR_OP_AAI_WP	0xad	/* Auto address increment word program */
+
+/* Used for S3AN flashes only */
+#define SPINOR_OP_XSE		0x50	/* Sector erase */
+#define SPINOR_OP_XPP		0x82	/* Page program */
+#define SPINOR_OP_XRDSR		0xd7	/* Read status register */
+
+#define XSR_PAGESIZE		BIT(0)	/* Page size in Po2 or Linear */
+#define XSR_RDY			BIT(7)	/* Ready */
+
+/* Used for Macronix and Winbond flashes. */
+#define SPINOR_OP_EN4B		0xb7	/* Enter 4-byte mode */
+#define SPINOR_OP_EX4B		0xe9	/* Exit 4-byte mode */
+
+/* Used for Spansion flashes only. */
+#define SPINOR_OP_BRWR		0x17	/* Bank register write */
+#define SPINOR_OP_CLSR		0x30	/* Clear status register 1 */
+
+/* Used for Micron flashes only. */
+#define SPINOR_OP_RD_EVCR      0x65    /* Read EVCR register */
+#define SPINOR_OP_WD_EVCR      0x61    /* Write EVCR register */
+
+/* Status Register bits. */
+#define SR_WIP			BIT(0)	/* Write in progress */
+#define SR_WEL			BIT(1)	/* Write enable latch */
+/* meaning of other SR_* bits may differ between vendors */
+#define SR_BP0			BIT(2)	/* Block protect 0 */
+#define SR_BP1			BIT(3)	/* Block protect 1 */
+#define SR_BP2			BIT(4)	/* Block protect 2 */
+#define SR_TB			BIT(5)	/* Top/Bottom protect */
+#define SR_SRWD			BIT(7)	/* SR write protect */
+/* Spansion/Cypress specific status bits */
+#define SR_E_ERR		BIT(5)
+#define SR_P_ERR		BIT(6)
+
+#define SR_QUAD_EN_MX		BIT(6)	/* Macronix Quad I/O */
+
+/* Enhanced Volatile Configuration Register bits */
+#define EVCR_QUAD_EN_MICRON	BIT(7)	/* Micron Quad I/O */
+
+/* Flag Status Register bits */
+#define FSR_READY		BIT(7)	/* Device status, 0 = Busy, 1 = Ready */
+#define FSR_E_ERR		BIT(5)	/* Erase operation status */
+#define FSR_P_ERR		BIT(4)	/* Program operation status */
+#define FSR_PT_ERR		BIT(1)	/* Protection error bit */
+
+/* Configuration Register bits. */
+#define CR_QUAD_EN_SPAN		BIT(1)	/* Spansion Quad I/O */
+
+/* Status Register 2 bits. */
+#define SR2_QUAD_EN_BIT7	BIT(7)
+
+/* Supported SPI protocols */
+#define SNOR_PROTO_INST_MASK	GENMASK(23, 16)
+#define SNOR_PROTO_INST_SHIFT	16
+#define SNOR_PROTO_INST(_nbits)	\
+	((((unsigned long)(_nbits)) << SNOR_PROTO_INST_SHIFT) & \
+	 SNOR_PROTO_INST_MASK)
+
+#define SNOR_PROTO_ADDR_MASK	GENMASK(15, 8)
+#define SNOR_PROTO_ADDR_SHIFT	8
+#define SNOR_PROTO_ADDR(_nbits)	\
+	((((unsigned long)(_nbits)) << SNOR_PROTO_ADDR_SHIFT) & \
+	 SNOR_PROTO_ADDR_MASK)
+
+#define SNOR_PROTO_DATA_MASK	GENMASK(7, 0)
+#define SNOR_PROTO_DATA_SHIFT	0
+#define SNOR_PROTO_DATA(_nbits)	\
+	((((unsigned long)(_nbits)) << SNOR_PROTO_DATA_SHIFT) & \
+	 SNOR_PROTO_DATA_MASK)
+
+#define SNOR_PROTO_IS_DTR	BIT(24)	/* Double Transfer Rate */
+
+#define SNOR_PROTO_STR(_inst_nbits, _addr_nbits, _data_nbits)	\
+	(SNOR_PROTO_INST(_inst_nbits) |				\
+	 SNOR_PROTO_ADDR(_addr_nbits) |				\
+	 SNOR_PROTO_DATA(_data_nbits))
+#define SNOR_PROTO_DTR(_inst_nbits, _addr_nbits, _data_nbits)	\
+	(SNOR_PROTO_IS_DTR |					\
+	 SNOR_PROTO_STR(_inst_nbits, _addr_nbits, _data_nbits))
+
+enum spi_nor_protocol {
+	SNOR_PROTO_1_1_1 = SNOR_PROTO_STR(1, 1, 1),
+	SNOR_PROTO_1_1_2 = SNOR_PROTO_STR(1, 1, 2),
+	SNOR_PROTO_1_1_4 = SNOR_PROTO_STR(1, 1, 4),
+	SNOR_PROTO_1_1_8 = SNOR_PROTO_STR(1, 1, 8),
+	SNOR_PROTO_1_2_2 = SNOR_PROTO_STR(1, 2, 2),
+	SNOR_PROTO_1_4_4 = SNOR_PROTO_STR(1, 4, 4),
+	SNOR_PROTO_1_8_8 = SNOR_PROTO_STR(1, 8, 8),
+	SNOR_PROTO_2_2_2 = SNOR_PROTO_STR(2, 2, 2),
+	SNOR_PROTO_4_4_4 = SNOR_PROTO_STR(4, 4, 4),
+	SNOR_PROTO_8_8_8 = SNOR_PROTO_STR(8, 8, 8),
+
+	SNOR_PROTO_1_1_1_DTR = SNOR_PROTO_DTR(1, 1, 1),
+	SNOR_PROTO_1_2_2_DTR = SNOR_PROTO_DTR(1, 2, 2),
+	SNOR_PROTO_1_4_4_DTR = SNOR_PROTO_DTR(1, 4, 4),
+	SNOR_PROTO_1_8_8_DTR = SNOR_PROTO_DTR(1, 8, 8),
+};
+
+static inline bool spi_nor_protocol_is_dtr(enum spi_nor_protocol proto)
+{
+	return !!(proto & SNOR_PROTO_IS_DTR);
+}
+
+static inline u8 spi_nor_get_protocol_inst_nbits(enum spi_nor_protocol proto)
+{
+	return ((unsigned long)(proto & SNOR_PROTO_INST_MASK)) >>
+		SNOR_PROTO_INST_SHIFT;
+}
+
+static inline u8 spi_nor_get_protocol_addr_nbits(enum spi_nor_protocol proto)
+{
+	return ((unsigned long)(proto & SNOR_PROTO_ADDR_MASK)) >>
+		SNOR_PROTO_ADDR_SHIFT;
+}
+
+static inline u8 spi_nor_get_protocol_data_nbits(enum spi_nor_protocol proto)
+{
+	return ((unsigned long)(proto & SNOR_PROTO_DATA_MASK)) >>
+		SNOR_PROTO_DATA_SHIFT;
+}
+
+static inline u8 spi_nor_get_protocol_width(enum spi_nor_protocol proto)
+{
+	return spi_nor_get_protocol_data_nbits(proto);
+}
+
+#define SPI_NOR_MAX_CMD_SIZE	8
+enum spi_nor_ops {
+	SPI_NOR_OPS_READ = 0,
+	SPI_NOR_OPS_WRITE,
+	SPI_NOR_OPS_ERASE,
+	SPI_NOR_OPS_LOCK,
+	SPI_NOR_OPS_UNLOCK,
+};
+
+enum spi_nor_option_flags {
+	SNOR_F_USE_FSR		= BIT(0),
+	SNOR_F_HAS_SR_TB	= BIT(1),
+	SNOR_F_NO_OP_CHIP_ERASE	= BIT(2),
+	SNOR_F_S3AN_ADDR_DEFAULT = BIT(3),
+	SNOR_F_READY_XSR_RDY	= BIT(4),
+	SNOR_F_USE_CLSR		= BIT(5),
+	SNOR_F_BROKEN_RESET	= BIT(6),
+};
+
+/**
+ * struct flash_info - Forward declaration of a structure used internally by
+ *		       spi_nor_scan()
+ */
+struct flash_info;
+
+/* TODO: Remove, once all users of spi_flash interface are moved to MTD */
+#define spi_flash spi_nor
+
+/**
+ * struct spi_nor - Structure for defining a the SPI NOR layer
+ * @mtd:		point to a mtd_info structure
+ * @lock:		the lock for the read/write/erase/lock/unlock operations
+ * @dev:		point to a spi device, or a spi nor controller device.
+ * @info:		spi-nor part JDEC MFR id and other info
+ * @page_size:		the page size of the SPI NOR
+ * @addr_width:		number of address bytes
+ * @erase_opcode:	the opcode for erasing a sector
+ * @read_opcode:	the read opcode
+ * @read_dummy:		the dummy needed by the read operation
+ * @program_opcode:	the program opcode
+ * @sst_write_second:	used by the SST write operation
+ * @flags:		flag options for the current SPI-NOR (SNOR_F_*)
+ * @read_proto:		the SPI protocol for read operations
+ * @write_proto:	the SPI protocol for write operations
+ * @reg_proto		the SPI protocol for read_reg/write_reg/erase operations
+ * @cmd_buf:		used by the write_reg
+ * @prepare:		[OPTIONAL] do some preparations for the
+ *			read/write/erase/lock/unlock operations
+ * @unprepare:		[OPTIONAL] do some post work after the
+ *			read/write/erase/lock/unlock operations
+ * @read_reg:		[DRIVER-SPECIFIC] read out the register
+ * @write_reg:		[DRIVER-SPECIFIC] write data to the register
+ * @read:		[DRIVER-SPECIFIC] read data from the SPI NOR
+ * @write:		[DRIVER-SPECIFIC] write data to the SPI NOR
+ * @erase:		[DRIVER-SPECIFIC] erase a sector of the SPI NOR
+ *			at the offset @offs; if not provided by the driver,
+ *			spi-nor will send the erase opcode via write_reg()
+ * @flash_lock:		[FLASH-SPECIFIC] lock a region of the SPI NOR
+ * @flash_unlock:	[FLASH-SPECIFIC] unlock a region of the SPI NOR
+ * @flash_is_locked:	[FLASH-SPECIFIC] check if a region of the SPI NOR is
+ * @quad_enable:	[FLASH-SPECIFIC] enables SPI NOR quad mode
+ *			completely locked
+ * @priv:		the private data
+ */
+struct spi_nor {
+	struct mtd_info		mtd;
+	struct udevice		*dev;
+	struct spi_slave	*spi;
+	const struct flash_info	*info;
+	u32			page_size;
+	u8			addr_width;
+	u8			erase_opcode;
+	u8			read_opcode;
+	u8			read_dummy;
+	u8			program_opcode;
+	enum spi_nor_protocol	read_proto;
+	enum spi_nor_protocol	write_proto;
+	enum spi_nor_protocol	reg_proto;
+	bool			sst_write_second;
+	u32			flags;
+	u8			cmd_buf[SPI_NOR_MAX_CMD_SIZE];
+
+	int (*prepare)(struct spi_nor *nor, enum spi_nor_ops ops);
+	void (*unprepare)(struct spi_nor *nor, enum spi_nor_ops ops);
+	int (*read_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, int len);
+	int (*write_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, int len);
+
+	ssize_t (*read)(struct spi_nor *nor, loff_t from,
+			size_t len, u_char *read_buf);
+	ssize_t (*write)(struct spi_nor *nor, loff_t to,
+			 size_t len, const u_char *write_buf);
+	int (*erase)(struct spi_nor *nor, loff_t offs);
+
+	int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+	int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+	int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+	int (*quad_enable)(struct spi_nor *nor);
+
+	void *priv;
+/* Compatibility for spi_flash, remove once sf layer is merged with mtd */
+	const char *name;
+	u32 size;
+	u32 sector_size;
+	u32 erase_size;
+};
+
+static inline void spi_nor_set_flash_node(struct spi_nor *nor,
+					  const struct device_node *np)
+{
+	mtd_set_of_node(&nor->mtd, np);
+}
+
+static inline const struct
+device_node *spi_nor_get_flash_node(struct spi_nor *nor)
+{
+	return mtd_get_of_node(&nor->mtd);
+}
+
+/**
+ * struct spi_nor_hwcaps - Structure for describing the hardware capabilies
+ * supported by the SPI controller (bus master).
+ * @mask:		the bitmask listing all the supported hw capabilies
+ */
+struct spi_nor_hwcaps {
+	u32	mask;
+};
+
+/*
+ *(Fast) Read capabilities.
+ * MUST be ordered by priority: the higher bit position, the higher priority.
+ * As a matter of performances, it is relevant to use Octo SPI protocols first,
+ * then Quad SPI protocols before Dual SPI protocols, Fast Read and lastly
+ * (Slow) Read.
+ */
+#define SNOR_HWCAPS_READ_MASK		GENMASK(14, 0)
+#define SNOR_HWCAPS_READ		BIT(0)
+#define SNOR_HWCAPS_READ_FAST		BIT(1)
+#define SNOR_HWCAPS_READ_1_1_1_DTR	BIT(2)
+
+#define SNOR_HWCAPS_READ_DUAL		GENMASK(6, 3)
+#define SNOR_HWCAPS_READ_1_1_2		BIT(3)
+#define SNOR_HWCAPS_READ_1_2_2		BIT(4)
+#define SNOR_HWCAPS_READ_2_2_2		BIT(5)
+#define SNOR_HWCAPS_READ_1_2_2_DTR	BIT(6)
+
+#define SNOR_HWCAPS_READ_QUAD		GENMASK(10, 7)
+#define SNOR_HWCAPS_READ_1_1_4		BIT(7)
+#define SNOR_HWCAPS_READ_1_4_4		BIT(8)
+#define SNOR_HWCAPS_READ_4_4_4		BIT(9)
+#define SNOR_HWCAPS_READ_1_4_4_DTR	BIT(10)
+
+#define SNOR_HWCPAS_READ_OCTO		GENMASK(14, 11)
+#define SNOR_HWCAPS_READ_1_1_8		BIT(11)
+#define SNOR_HWCAPS_READ_1_8_8		BIT(12)
+#define SNOR_HWCAPS_READ_8_8_8		BIT(13)
+#define SNOR_HWCAPS_READ_1_8_8_DTR	BIT(14)
+
+/*
+ * Page Program capabilities.
+ * MUST be ordered by priority: the higher bit position, the higher priority.
+ * Like (Fast) Read capabilities, Octo/Quad SPI protocols are preferred to the
+ * legacy SPI 1-1-1 protocol.
+ * Note that Dual Page Programs are not supported because there is no existing
+ * JEDEC/SFDP standard to define them. Also at this moment no SPI flash memory
+ * implements such commands.
+ */
+#define SNOR_HWCAPS_PP_MASK	GENMASK(22, 16)
+#define SNOR_HWCAPS_PP		BIT(16)
+
+#define SNOR_HWCAPS_PP_QUAD	GENMASK(19, 17)
+#define SNOR_HWCAPS_PP_1_1_4	BIT(17)
+#define SNOR_HWCAPS_PP_1_4_4	BIT(18)
+#define SNOR_HWCAPS_PP_4_4_4	BIT(19)
+
+#define SNOR_HWCAPS_PP_OCTO	GENMASK(22, 20)
+#define SNOR_HWCAPS_PP_1_1_8	BIT(20)
+#define SNOR_HWCAPS_PP_1_8_8	BIT(21)
+#define SNOR_HWCAPS_PP_8_8_8	BIT(22)
+
+/**
+ * spi_nor_scan() - scan the SPI NOR
+ * @nor:	the spi_nor structure
+ *
+ * The drivers can use this function to scan the SPI NOR.
+ * In the scanning, it will try to get all the necessary information to
+ * fill the mtd_info{} and the spi_nor{}.
+ *
+ * Return: 0 for success, others for failure.
+ */
+int spi_nor_scan(struct spi_nor *nor);
+
+#endif