openwrtv4/target/linux/bcm53xx/patches-3.14/001-mtd-spi-nor.patch

This patches adds the SPI-NOR device support code form kernel 3.17-rc1.
This patch does not contain any further code not in this mainline kernel.

--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -366,6 +366,8 @@ source "drivers/mtd/onenand/Kconfig"
 
 source "drivers/mtd/lpddr/Kconfig"
 
+source "drivers/mtd/spi-nor/Kconfig"
+
 source "drivers/mtd/ubi/Kconfig"
 
 endif # MTD
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -35,4 +35,5 @@ inftl-objs		:= inftlcore.o inftlmount.o
 
 obj-y		+= chips/ lpddr/ maps/ devices/ nand/ onenand/ tests/
 
+obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor/
 obj-$(CONFIG_MTD_UBI)		+= ubi/
--- /dev/null
+++ b/drivers/mtd/spi-nor/fsl-quadspi.c
@@ -0,0 +1,1009 @@
+/*
+ * Freescale QuadSPI driver.
+ *
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+#include <linux/completion.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/spi-nor.h>
+
+/* The registers */
+#define QUADSPI_MCR			0x00
+#define QUADSPI_MCR_RESERVED_SHIFT	16
+#define QUADSPI_MCR_RESERVED_MASK	(0xF << QUADSPI_MCR_RESERVED_SHIFT)
+#define QUADSPI_MCR_MDIS_SHIFT		14
+#define QUADSPI_MCR_MDIS_MASK		(1 << QUADSPI_MCR_MDIS_SHIFT)
+#define QUADSPI_MCR_CLR_TXF_SHIFT	11
+#define QUADSPI_MCR_CLR_TXF_MASK	(1 << QUADSPI_MCR_CLR_TXF_SHIFT)
+#define QUADSPI_MCR_CLR_RXF_SHIFT	10
+#define QUADSPI_MCR_CLR_RXF_MASK	(1 << QUADSPI_MCR_CLR_RXF_SHIFT)
+#define QUADSPI_MCR_DDR_EN_SHIFT	7
+#define QUADSPI_MCR_DDR_EN_MASK		(1 << QUADSPI_MCR_DDR_EN_SHIFT)
+#define QUADSPI_MCR_END_CFG_SHIFT	2
+#define QUADSPI_MCR_END_CFG_MASK	(3 << QUADSPI_MCR_END_CFG_SHIFT)
+#define QUADSPI_MCR_SWRSTHD_SHIFT	1
+#define QUADSPI_MCR_SWRSTHD_MASK	(1 << QUADSPI_MCR_SWRSTHD_SHIFT)
+#define QUADSPI_MCR_SWRSTSD_SHIFT	0
+#define QUADSPI_MCR_SWRSTSD_MASK	(1 << QUADSPI_MCR_SWRSTSD_SHIFT)
+
+#define QUADSPI_IPCR			0x08
+#define QUADSPI_IPCR_SEQID_SHIFT	24
+#define QUADSPI_IPCR_SEQID_MASK		(0xF << QUADSPI_IPCR_SEQID_SHIFT)
+
+#define QUADSPI_BUF0CR			0x10
+#define QUADSPI_BUF1CR			0x14
+#define QUADSPI_BUF2CR			0x18
+#define QUADSPI_BUFXCR_INVALID_MSTRID	0xe
+
+#define QUADSPI_BUF3CR			0x1c
+#define QUADSPI_BUF3CR_ALLMST_SHIFT	31
+#define QUADSPI_BUF3CR_ALLMST		(1 << QUADSPI_BUF3CR_ALLMST_SHIFT)
+
+#define QUADSPI_BFGENCR			0x20
+#define QUADSPI_BFGENCR_PAR_EN_SHIFT	16
+#define QUADSPI_BFGENCR_PAR_EN_MASK	(1 << (QUADSPI_BFGENCR_PAR_EN_SHIFT))
+#define QUADSPI_BFGENCR_SEQID_SHIFT	12
+#define QUADSPI_BFGENCR_SEQID_MASK	(0xF << QUADSPI_BFGENCR_SEQID_SHIFT)
+
+#define QUADSPI_BUF0IND			0x30
+#define QUADSPI_BUF1IND			0x34
+#define QUADSPI_BUF2IND			0x38
+#define QUADSPI_SFAR			0x100
+
+#define QUADSPI_SMPR			0x108
+#define QUADSPI_SMPR_DDRSMP_SHIFT	16
+#define QUADSPI_SMPR_DDRSMP_MASK	(7 << QUADSPI_SMPR_DDRSMP_SHIFT)
+#define QUADSPI_SMPR_FSDLY_SHIFT	6
+#define QUADSPI_SMPR_FSDLY_MASK		(1 << QUADSPI_SMPR_FSDLY_SHIFT)
+#define QUADSPI_SMPR_FSPHS_SHIFT	5
+#define QUADSPI_SMPR_FSPHS_MASK		(1 << QUADSPI_SMPR_FSPHS_SHIFT)
+#define QUADSPI_SMPR_HSENA_SHIFT	0
+#define QUADSPI_SMPR_HSENA_MASK		(1 << QUADSPI_SMPR_HSENA_SHIFT)
+
+#define QUADSPI_RBSR			0x10c
+#define QUADSPI_RBSR_RDBFL_SHIFT	8
+#define QUADSPI_RBSR_RDBFL_MASK		(0x3F << QUADSPI_RBSR_RDBFL_SHIFT)
+
+#define QUADSPI_RBCT			0x110
+#define QUADSPI_RBCT_WMRK_MASK		0x1F
+#define QUADSPI_RBCT_RXBRD_SHIFT	8
+#define QUADSPI_RBCT_RXBRD_USEIPS	(0x1 << QUADSPI_RBCT_RXBRD_SHIFT)
+
+#define QUADSPI_TBSR			0x150
+#define QUADSPI_TBDR			0x154
+#define QUADSPI_SR			0x15c
+#define QUADSPI_SR_IP_ACC_SHIFT		1
+#define QUADSPI_SR_IP_ACC_MASK		(0x1 << QUADSPI_SR_IP_ACC_SHIFT)
+#define QUADSPI_SR_AHB_ACC_SHIFT	2
+#define QUADSPI_SR_AHB_ACC_MASK		(0x1 << QUADSPI_SR_AHB_ACC_SHIFT)
+
+#define QUADSPI_FR			0x160
+#define QUADSPI_FR_TFF_MASK		0x1
+
+#define QUADSPI_SFA1AD			0x180
+#define QUADSPI_SFA2AD			0x184
+#define QUADSPI_SFB1AD			0x188
+#define QUADSPI_SFB2AD			0x18c
+#define QUADSPI_RBDR			0x200
+
+#define QUADSPI_LUTKEY			0x300
+#define QUADSPI_LUTKEY_VALUE		0x5AF05AF0
+
+#define QUADSPI_LCKCR			0x304
+#define QUADSPI_LCKER_LOCK		0x1
+#define QUADSPI_LCKER_UNLOCK		0x2
+
+#define QUADSPI_RSER			0x164
+#define QUADSPI_RSER_TFIE		(0x1 << 0)
+
+#define QUADSPI_LUT_BASE		0x310
+
+/*
+ * The definition of the LUT register shows below:
+ *
+ *  ---------------------------------------------------
+ *  | INSTR1 | PAD1 | OPRND1 | INSTR0 | PAD0 | OPRND0 |
+ *  ---------------------------------------------------
+ */
+#define OPRND0_SHIFT		0
+#define PAD0_SHIFT		8
+#define INSTR0_SHIFT		10
+#define OPRND1_SHIFT		16
+
+/* Instruction set for the LUT register. */
+#define LUT_STOP		0
+#define LUT_CMD			1
+#define LUT_ADDR		2
+#define LUT_DUMMY		3
+#define LUT_MODE		4
+#define LUT_MODE2		5
+#define LUT_MODE4		6
+#define LUT_READ		7
+#define LUT_WRITE		8
+#define LUT_JMP_ON_CS		9
+#define LUT_ADDR_DDR		10
+#define LUT_MODE_DDR		11
+#define LUT_MODE2_DDR		12
+#define LUT_MODE4_DDR		13
+#define LUT_READ_DDR		14
+#define LUT_WRITE_DDR		15
+#define LUT_DATA_LEARN		16
+
+/*
+ * The PAD definitions for LUT register.
+ *
+ * The pad stands for the lines number of IO[0:3].
+ * For example, the Quad read need four IO lines, so you should
+ * set LUT_PAD4 which means we use four IO lines.
+ */
+#define LUT_PAD1		0
+#define LUT_PAD2		1
+#define LUT_PAD4		2
+
+/* Oprands for the LUT register. */
+#define ADDR24BIT		0x18
+#define ADDR32BIT		0x20
+
+/* Macros for constructing the LUT register. */
+#define LUT0(ins, pad, opr)						\
+		(((opr) << OPRND0_SHIFT) | ((LUT_##pad) << PAD0_SHIFT) | \
+		((LUT_##ins) << INSTR0_SHIFT))
+
+#define LUT1(ins, pad, opr)	(LUT0(ins, pad, opr) << OPRND1_SHIFT)
+
+/* other macros for LUT register. */
+#define QUADSPI_LUT(x)          (QUADSPI_LUT_BASE + (x) * 4)
+#define QUADSPI_LUT_NUM		64
+
+/* SEQID -- we can have 16 seqids at most. */
+#define SEQID_QUAD_READ		0
+#define SEQID_WREN		1
+#define SEQID_WRDI		2
+#define SEQID_RDSR		3
+#define SEQID_SE		4
+#define SEQID_CHIP_ERASE	5
+#define SEQID_PP		6
+#define SEQID_RDID		7
+#define SEQID_WRSR		8
+#define SEQID_RDCR		9
+#define SEQID_EN4B		10
+#define SEQID_BRWR		11
+
+enum fsl_qspi_devtype {
+	FSL_QUADSPI_VYBRID,
+	FSL_QUADSPI_IMX6SX,
+};
+
+struct fsl_qspi_devtype_data {
+	enum fsl_qspi_devtype devtype;
+	int rxfifo;
+	int txfifo;
+};
+
+static struct fsl_qspi_devtype_data vybrid_data = {
+	.devtype = FSL_QUADSPI_VYBRID,
+	.rxfifo = 128,
+	.txfifo = 64
+};
+
+static struct fsl_qspi_devtype_data imx6sx_data = {
+	.devtype = FSL_QUADSPI_IMX6SX,
+	.rxfifo = 128,
+	.txfifo = 512
+};
+
+#define FSL_QSPI_MAX_CHIP	4
+struct fsl_qspi {
+	struct mtd_info mtd[FSL_QSPI_MAX_CHIP];
+	struct spi_nor nor[FSL_QSPI_MAX_CHIP];
+	void __iomem *iobase;
+	void __iomem *ahb_base; /* Used when read from AHB bus */
+	u32 memmap_phy;
+	struct clk *clk, *clk_en;
+	struct device *dev;
+	struct completion c;
+	struct fsl_qspi_devtype_data *devtype_data;
+	u32 nor_size;
+	u32 nor_num;
+	u32 clk_rate;
+	unsigned int chip_base_addr; /* We may support two chips. */
+};
+
+static inline int is_vybrid_qspi(struct fsl_qspi *q)
+{
+	return q->devtype_data->devtype == FSL_QUADSPI_VYBRID;
+}
+
+static inline int is_imx6sx_qspi(struct fsl_qspi *q)
+{
+	return q->devtype_data->devtype == FSL_QUADSPI_IMX6SX;
+}
+
+/*
+ * An IC bug makes us to re-arrange the 32-bit data.
+ * The following chips, such as IMX6SLX, have fixed this bug.
+ */
+static inline u32 fsl_qspi_endian_xchg(struct fsl_qspi *q, u32 a)
+{
+	return is_vybrid_qspi(q) ? __swab32(a) : a;
+}
+
+static inline void fsl_qspi_unlock_lut(struct fsl_qspi *q)
+{
+	writel(QUADSPI_LUTKEY_VALUE, q->iobase + QUADSPI_LUTKEY);
+	writel(QUADSPI_LCKER_UNLOCK, q->iobase + QUADSPI_LCKCR);
+}
+
+static inline void fsl_qspi_lock_lut(struct fsl_qspi *q)
+{
+	writel(QUADSPI_LUTKEY_VALUE, q->iobase + QUADSPI_LUTKEY);
+	writel(QUADSPI_LCKER_LOCK, q->iobase + QUADSPI_LCKCR);
+}
+
+static irqreturn_t fsl_qspi_irq_handler(int irq, void *dev_id)
+{
+	struct fsl_qspi *q = dev_id;
+	u32 reg;
+
+	/* clear interrupt */
+	reg = readl(q->iobase + QUADSPI_FR);
+	writel(reg, q->iobase + QUADSPI_FR);
+
+	if (reg & QUADSPI_FR_TFF_MASK)
+		complete(&q->c);
+
+	dev_dbg(q->dev, "QUADSPI_FR : 0x%.8x:0x%.8x\n", q->chip_base_addr, reg);
+	return IRQ_HANDLED;
+}
+
+static void fsl_qspi_init_lut(struct fsl_qspi *q)
+{
+	void __iomem *base = q->iobase;
+	int rxfifo = q->devtype_data->rxfifo;
+	u32 lut_base;
+	u8 cmd, addrlen, dummy;
+	int i;
+
+	fsl_qspi_unlock_lut(q);
+
+	/* Clear all the LUT table */
+	for (i = 0; i < QUADSPI_LUT_NUM; i++)
+		writel(0, base + QUADSPI_LUT_BASE + i * 4);
+
+	/* Quad Read */
+	lut_base = SEQID_QUAD_READ * 4;
+
+	if (q->nor_size <= SZ_16M) {
+		cmd = SPINOR_OP_READ_1_1_4;
+		addrlen = ADDR24BIT;
+		dummy = 8;
+	} else {
+		/* use the 4-byte address */
+		cmd = SPINOR_OP_READ_1_1_4;
+		addrlen = ADDR32BIT;
+		dummy = 8;
+	}
+
+	writel(LUT0(CMD, PAD1, cmd) | LUT1(ADDR, PAD1, addrlen),
+			base + QUADSPI_LUT(lut_base));
+	writel(LUT0(DUMMY, PAD1, dummy) | LUT1(READ, PAD4, rxfifo),
+			base + QUADSPI_LUT(lut_base + 1));
+
+	/* Write enable */
+	lut_base = SEQID_WREN * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_WREN), base + QUADSPI_LUT(lut_base));
+
+	/* Page Program */
+	lut_base = SEQID_PP * 4;
+
+	if (q->nor_size <= SZ_16M) {
+		cmd = SPINOR_OP_PP;
+		addrlen = ADDR24BIT;
+	} else {
+		/* use the 4-byte address */
+		cmd = SPINOR_OP_PP;
+		addrlen = ADDR32BIT;
+	}
+
+	writel(LUT0(CMD, PAD1, cmd) | LUT1(ADDR, PAD1, addrlen),
+			base + QUADSPI_LUT(lut_base));
+	writel(LUT0(WRITE, PAD1, 0), base + QUADSPI_LUT(lut_base + 1));
+
+	/* Read Status */
+	lut_base = SEQID_RDSR * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_RDSR) | LUT1(READ, PAD1, 0x1),
+			base + QUADSPI_LUT(lut_base));
+
+	/* Erase a sector */
+	lut_base = SEQID_SE * 4;
+
+	if (q->nor_size <= SZ_16M) {
+		cmd = SPINOR_OP_SE;
+		addrlen = ADDR24BIT;
+	} else {
+		/* use the 4-byte address */
+		cmd = SPINOR_OP_SE;
+		addrlen = ADDR32BIT;
+	}
+
+	writel(LUT0(CMD, PAD1, cmd) | LUT1(ADDR, PAD1, addrlen),
+			base + QUADSPI_LUT(lut_base));
+
+	/* Erase the whole chip */
+	lut_base = SEQID_CHIP_ERASE * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_CHIP_ERASE),
+			base + QUADSPI_LUT(lut_base));
+
+	/* READ ID */
+	lut_base = SEQID_RDID * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_RDID) | LUT1(READ, PAD1, 0x8),
+			base + QUADSPI_LUT(lut_base));
+
+	/* Write Register */
+	lut_base = SEQID_WRSR * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_WRSR) | LUT1(WRITE, PAD1, 0x2),
+			base + QUADSPI_LUT(lut_base));
+
+	/* Read Configuration Register */
+	lut_base = SEQID_RDCR * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_RDCR) | LUT1(READ, PAD1, 0x1),
+			base + QUADSPI_LUT(lut_base));
+
+	/* Write disable */
+	lut_base = SEQID_WRDI * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_WRDI), base + QUADSPI_LUT(lut_base));
+
+	/* Enter 4 Byte Mode (Micron) */
+	lut_base = SEQID_EN4B * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_EN4B), base + QUADSPI_LUT(lut_base));
+
+	/* Enter 4 Byte Mode (Spansion) */
+	lut_base = SEQID_BRWR * 4;
+	writel(LUT0(CMD, PAD1, SPINOR_OP_BRWR), base + QUADSPI_LUT(lut_base));
+
+	fsl_qspi_lock_lut(q);
+}
+
+/* Get the SEQID for the command */
+static int fsl_qspi_get_seqid(struct fsl_qspi *q, u8 cmd)
+{
+	switch (cmd) {
+	case SPINOR_OP_READ_1_1_4:
+		return SEQID_QUAD_READ;
+	case SPINOR_OP_WREN:
+		return SEQID_WREN;
+	case SPINOR_OP_WRDI:
+		return SEQID_WRDI;
+	case SPINOR_OP_RDSR:
+		return SEQID_RDSR;
+	case SPINOR_OP_SE:
+		return SEQID_SE;
+	case SPINOR_OP_CHIP_ERASE:
+		return SEQID_CHIP_ERASE;
+	case SPINOR_OP_PP:
+		return SEQID_PP;
+	case SPINOR_OP_RDID:
+		return SEQID_RDID;
+	case SPINOR_OP_WRSR:
+		return SEQID_WRSR;
+	case SPINOR_OP_RDCR:
+		return SEQID_RDCR;
+	case SPINOR_OP_EN4B:
+		return SEQID_EN4B;
+	case SPINOR_OP_BRWR:
+		return SEQID_BRWR;
+	default:
+		dev_err(q->dev, "Unsupported cmd 0x%.2x\n", cmd);
+		break;
+	}
+	return -EINVAL;
+}
+
+static int
+fsl_qspi_runcmd(struct fsl_qspi *q, u8 cmd, unsigned int addr, int len)
+{
+	void __iomem *base = q->iobase;
+	int seqid;
+	u32 reg, reg2;
+	int err;
+
+	init_completion(&q->c);
+	dev_dbg(q->dev, "to 0x%.8x:0x%.8x, len:%d, cmd:%.2x\n",
+			q->chip_base_addr, addr, len, cmd);
+
+	/* save the reg */
+	reg = readl(base + QUADSPI_MCR);
+
+	writel(q->memmap_phy + q->chip_base_addr + addr, base + QUADSPI_SFAR);
+	writel(QUADSPI_RBCT_WMRK_MASK | QUADSPI_RBCT_RXBRD_USEIPS,
+			base + QUADSPI_RBCT);
+	writel(reg | QUADSPI_MCR_CLR_RXF_MASK, base + QUADSPI_MCR);
+
+	do {
+		reg2 = readl(base + QUADSPI_SR);
+		if (reg2 & (QUADSPI_SR_IP_ACC_MASK | QUADSPI_SR_AHB_ACC_MASK)) {
+			udelay(1);
+			dev_dbg(q->dev, "The controller is busy, 0x%x\n", reg2);
+			continue;
+		}
+		break;
+	} while (1);
+
+	/* trigger the LUT now */
+	seqid = fsl_qspi_get_seqid(q, cmd);
+	writel((seqid << QUADSPI_IPCR_SEQID_SHIFT) | len, base + QUADSPI_IPCR);
+
+	/* Wait for the interrupt. */
+	err = wait_for_completion_timeout(&q->c, msecs_to_jiffies(1000));
+	if (!err) {
+		dev_err(q->dev,
+			"cmd 0x%.2x timeout, addr@%.8x, FR:0x%.8x, SR:0x%.8x\n",
+			cmd, addr, readl(base + QUADSPI_FR),
+			readl(base + QUADSPI_SR));
+		err = -ETIMEDOUT;
+	} else {
+		err = 0;
+	}
+
+	/* restore the MCR */
+	writel(reg, base + QUADSPI_MCR);
+
+	return err;
+}
+
+/* Read out the data from the QUADSPI_RBDR buffer registers. */
+static void fsl_qspi_read_data(struct fsl_qspi *q, int len, u8 *rxbuf)
+{
+	u32 tmp;
+	int i = 0;
+
+	while (len > 0) {
+		tmp = readl(q->iobase + QUADSPI_RBDR + i * 4);
+		tmp = fsl_qspi_endian_xchg(q, tmp);
+		dev_dbg(q->dev, "chip addr:0x%.8x, rcv:0x%.8x\n",
+				q->chip_base_addr, tmp);
+
+		if (len >= 4) {
+			*((u32 *)rxbuf) = tmp;
+			rxbuf += 4;
+		} else {
+			memcpy(rxbuf, &tmp, len);
+			break;
+		}
+
+		len -= 4;
+		i++;
+	}
+}
+
+/*
+ * If we have changed the content of the flash by writing or erasing,
+ * we need to invalidate the AHB buffer. If we do not do so, we may read out
+ * the wrong data. The spec tells us reset the AHB domain and Serial Flash
+ * domain at the same time.
+ */
+static inline void fsl_qspi_invalid(struct fsl_qspi *q)
+{
+	u32 reg;
+
+	reg = readl(q->iobase + QUADSPI_MCR);
+	reg |= QUADSPI_MCR_SWRSTHD_MASK | QUADSPI_MCR_SWRSTSD_MASK;
+	writel(reg, q->iobase + QUADSPI_MCR);
+
+	/*
+	 * The minimum delay : 1 AHB + 2 SFCK clocks.
+	 * Delay 1 us is enough.
+	 */
+	udelay(1);
+
+	reg &= ~(QUADSPI_MCR_SWRSTHD_MASK | QUADSPI_MCR_SWRSTSD_MASK);
+	writel(reg, q->iobase + QUADSPI_MCR);
+}
+
+static int fsl_qspi_nor_write(struct fsl_qspi *q, struct spi_nor *nor,
+				u8 opcode, unsigned int to, u32 *txbuf,
+				unsigned count, size_t *retlen)
+{
+	int ret, i, j;
+	u32 tmp;
+
+	dev_dbg(q->dev, "to 0x%.8x:0x%.8x, len : %d\n",
+		q->chip_base_addr, to, count);
+
+	/* clear the TX FIFO. */
+	tmp = readl(q->iobase + QUADSPI_MCR);
+	writel(tmp | QUADSPI_MCR_CLR_RXF_MASK, q->iobase + QUADSPI_MCR);
+
+	/* fill the TX data to the FIFO */
+	for (j = 0, i = ((count + 3) / 4); j < i; j++) {
+		tmp = fsl_qspi_endian_xchg(q, *txbuf);
+		writel(tmp, q->iobase + QUADSPI_TBDR);
+		txbuf++;
+	}
+
+	/* Trigger it */
+	ret = fsl_qspi_runcmd(q, opcode, to, count);
+
+	if (ret == 0 && retlen)
+		*retlen += count;
+
+	return ret;
+}
+
+static void fsl_qspi_set_map_addr(struct fsl_qspi *q)
+{
+	int nor_size = q->nor_size;
+	void __iomem *base = q->iobase;
+
+	writel(nor_size + q->memmap_phy, base + QUADSPI_SFA1AD);
+	writel(nor_size * 2 + q->memmap_phy, base + QUADSPI_SFA2AD);
+	writel(nor_size * 3 + q->memmap_phy, base + QUADSPI_SFB1AD);
+	writel(nor_size * 4 + q->memmap_phy, base + QUADSPI_SFB2AD);
+}
+
+/*
+ * There are two different ways to read out the data from the flash:
+ *  the "IP Command Read" and the "AHB Command Read".
+ *
+ * The IC guy suggests we use the "AHB Command Read" which is faster
+ * then the "IP Command Read". (What's more is that there is a bug in
+ * the "IP Command Read" in the Vybrid.)
+ *
+ * After we set up the registers for the "AHB Command Read", we can use
+ * the memcpy to read the data directly. A "missed" access to the buffer
+ * causes the controller to clear the buffer, and use the sequence pointed
+ * by the QUADSPI_BFGENCR[SEQID] to initiate a read from the flash.
+ */
+static void fsl_qspi_init_abh_read(struct fsl_qspi *q)
+{
+	void __iomem *base = q->iobase;
+	int seqid;
+
+	/* AHB configuration for access buffer 0/1/2 .*/
+	writel(QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF0CR);
+	writel(QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF1CR);
+	writel(QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF2CR);
+	writel(QUADSPI_BUF3CR_ALLMST, base + QUADSPI_BUF3CR);
+
+	/* We only use the buffer3 */
+	writel(0, base + QUADSPI_BUF0IND);
+	writel(0, base + QUADSPI_BUF1IND);
+	writel(0, base + QUADSPI_BUF2IND);
+
+	/* Set the default lut sequence for AHB Read. */
+	seqid = fsl_qspi_get_seqid(q, q->nor[0].read_opcode);
+	writel(seqid << QUADSPI_BFGENCR_SEQID_SHIFT,
+		q->iobase + QUADSPI_BFGENCR);
+}
+
+/* We use this function to do some basic init for spi_nor_scan(). */
+static int fsl_qspi_nor_setup(struct fsl_qspi *q)
+{
+	void __iomem *base = q->iobase;
+	u32 reg;
+	int ret;
+
+	/* the default frequency, we will change it in the future.*/
+	ret = clk_set_rate(q->clk, 66000000);
+	if (ret)
+		return ret;
+
+	/* Init the LUT table. */
+	fsl_qspi_init_lut(q);
+
+	/* Disable the module */
+	writel(QUADSPI_MCR_MDIS_MASK | QUADSPI_MCR_RESERVED_MASK,
+			base + QUADSPI_MCR);
+
+	reg = readl(base + QUADSPI_SMPR);
+	writel(reg & ~(QUADSPI_SMPR_FSDLY_MASK
+			| QUADSPI_SMPR_FSPHS_MASK
+			| QUADSPI_SMPR_HSENA_MASK
+			| QUADSPI_SMPR_DDRSMP_MASK), base + QUADSPI_SMPR);
+
+	/* Enable the module */
+	writel(QUADSPI_MCR_RESERVED_MASK | QUADSPI_MCR_END_CFG_MASK,
+			base + QUADSPI_MCR);
+
+	/* enable the interrupt */
+	writel(QUADSPI_RSER_TFIE, q->iobase + QUADSPI_RSER);
+
+	return 0;
+}
+
+static int fsl_qspi_nor_setup_last(struct fsl_qspi *q)
+{
+	unsigned long rate = q->clk_rate;
+	int ret;
+
+	if (is_imx6sx_qspi(q))
+		rate *= 4;
+
+	ret = clk_set_rate(q->clk, rate);
+	if (ret)
+		return ret;
+
+	/* Init the LUT table again. */
+	fsl_qspi_init_lut(q);
+
+	/* Init for AHB read */
+	fsl_qspi_init_abh_read(q);
+
+	return 0;
+}
+
+static struct of_device_id fsl_qspi_dt_ids[] = {
+	{ .compatible = "fsl,vf610-qspi", .data = (void *)&vybrid_data, },
+	{ .compatible = "fsl,imx6sx-qspi", .data = (void *)&imx6sx_data, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, fsl_qspi_dt_ids);
+
+static void fsl_qspi_set_base_addr(struct fsl_qspi *q, struct spi_nor *nor)
+{
+	q->chip_base_addr = q->nor_size * (nor - q->nor);
+}
+
+static int fsl_qspi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
+{
+	int ret;
+	struct fsl_qspi *q = nor->priv;
+
+	ret = fsl_qspi_runcmd(q, opcode, 0, len);
+	if (ret)
+		return ret;
+
+	fsl_qspi_read_data(q, len, buf);
+	return 0;
+}
+
+static int fsl_qspi_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len,
+			int write_enable)
+{
+	struct fsl_qspi *q = nor->priv;
+	int ret;
+
+	if (!buf) {
+		ret = fsl_qspi_runcmd(q, opcode, 0, 1);
+		if (ret)
+			return ret;
+
+		if (opcode == SPINOR_OP_CHIP_ERASE)
+			fsl_qspi_invalid(q);
+
+	} else if (len > 0) {
+		ret = fsl_qspi_nor_write(q, nor, opcode, 0,
+					(u32 *)buf, len, NULL);
+	} else {
+		dev_err(q->dev, "invalid cmd %d\n", opcode);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static void fsl_qspi_write(struct spi_nor *nor, loff_t to,
+		size_t len, size_t *retlen, const u_char *buf)
+{
+	struct fsl_qspi *q = nor->priv;
+
+	fsl_qspi_nor_write(q, nor, nor->program_opcode, to,
+				(u32 *)buf, len, retlen);
+
+	/* invalid the data in the AHB buffer. */
+	fsl_qspi_invalid(q);
+}
+
+static int fsl_qspi_read(struct spi_nor *nor, loff_t from,
+		size_t len, size_t *retlen, u_char *buf)
+{
+	struct fsl_qspi *q = nor->priv;
+	u8 cmd = nor->read_opcode;
+	int ret;
+
+	dev_dbg(q->dev, "cmd [%x],read from (0x%p, 0x%.8x, 0x%.8x),len:%d\n",
+		cmd, q->ahb_base, q->chip_base_addr, (unsigned int)from, len);
+
+	/* Wait until the previous command is finished. */
+	ret = nor->wait_till_ready(nor);
+	if (ret)
+		return ret;
+
+	/* Read out the data directly from the AHB buffer.*/
+	memcpy(buf, q->ahb_base + q->chip_base_addr + from, len);
+
+	*retlen += len;
+	return 0;
+}
+
+static int fsl_qspi_erase(struct spi_nor *nor, loff_t offs)
+{
+	struct fsl_qspi *q = nor->priv;
+	int ret;
+
+	dev_dbg(nor->dev, "%dKiB at 0x%08x:0x%08x\n",
+		nor->mtd->erasesize / 1024, q->chip_base_addr, (u32)offs);
+
+	/* Wait until finished previous write command. */
+	ret = nor->wait_till_ready(nor);
+	if (ret)
+		return ret;
+
+	/* Send write enable, then erase commands. */
+	ret = nor->write_reg(nor, SPINOR_OP_WREN, NULL, 0, 0);
+	if (ret)
+		return ret;
+
+	ret = fsl_qspi_runcmd(q, nor->erase_opcode, offs, 0);
+	if (ret)
+		return ret;
+
+	fsl_qspi_invalid(q);
+	return 0;
+}
+
+static int fsl_qspi_prep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+	struct fsl_qspi *q = nor->priv;
+	int ret;
+
+	ret = clk_enable(q->clk_en);
+	if (ret)
+		return ret;
+
+	ret = clk_enable(q->clk);
+	if (ret) {
+		clk_disable(q->clk_en);
+		return ret;
+	}
+
+	fsl_qspi_set_base_addr(q, nor);
+	return 0;
+}
+
+static void fsl_qspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+	struct fsl_qspi *q = nor->priv;
+
+	clk_disable(q->clk);
+	clk_disable(q->clk_en);
+}
+
+static int fsl_qspi_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mtd_part_parser_data ppdata;
+	struct device *dev = &pdev->dev;
+	struct fsl_qspi *q;
+	struct resource *res;
+	struct spi_nor *nor;
+	struct mtd_info *mtd;
+	int ret, i = 0;
+	bool has_second_chip = false;
+	const struct of_device_id *of_id =
+			of_match_device(fsl_qspi_dt_ids, &pdev->dev);
+
+	q = devm_kzalloc(dev, sizeof(*q), GFP_KERNEL);
+	if (!q)
+		return -ENOMEM;
+
+	q->nor_num = of_get_child_count(dev->of_node);
+	if (!q->nor_num || q->nor_num > FSL_QSPI_MAX_CHIP)
+		return -ENODEV;
+
+	/* find the resources */
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "QuadSPI");
+	q->iobase = devm_ioremap_resource(dev, res);
+	if (IS_ERR(q->iobase)) {
+		ret = PTR_ERR(q->iobase);
+		goto map_failed;
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+					"QuadSPI-memory");
+	q->ahb_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(q->ahb_base)) {
+		ret = PTR_ERR(q->ahb_base);
+		goto map_failed;
+	}
+	q->memmap_phy = res->start;
+
+	/* find the clocks */
+	q->clk_en = devm_clk_get(dev, "qspi_en");
+	if (IS_ERR(q->clk_en)) {
+		ret = PTR_ERR(q->clk_en);
+		goto map_failed;
+	}
+
+	q->clk = devm_clk_get(dev, "qspi");
+	if (IS_ERR(q->clk)) {
+		ret = PTR_ERR(q->clk);
+		goto map_failed;
+	}
+
+	ret = clk_prepare_enable(q->clk_en);
+	if (ret) {
+		dev_err(dev, "can not enable the qspi_en clock\n");
+		goto map_failed;
+	}
+
+	ret = clk_prepare_enable(q->clk);
+	if (ret) {
+		clk_disable_unprepare(q->clk_en);
+		dev_err(dev, "can not enable the qspi clock\n");
+		goto map_failed;
+	}
+
+	/* find the irq */
+	ret = platform_get_irq(pdev, 0);
+	if (ret < 0) {
+		dev_err(dev, "failed to get the irq\n");
+		goto irq_failed;
+	}
+
+	ret = devm_request_irq(dev, ret,
+			fsl_qspi_irq_handler, 0, pdev->name, q);
+	if (ret) {
+		dev_err(dev, "failed to request irq.\n");
+		goto irq_failed;
+	}
+
+	q->dev = dev;
+	q->devtype_data = (struct fsl_qspi_devtype_data *)of_id->data;
+	platform_set_drvdata(pdev, q);
+
+	ret = fsl_qspi_nor_setup(q);
+	if (ret)
+		goto irq_failed;
+
+	if (of_get_property(np, "fsl,qspi-has-second-chip", NULL))
+		has_second_chip = true;
+
+	/* iterate the subnodes. */
+	for_each_available_child_of_node(dev->of_node, np) {
+		const struct spi_device_id *id;
+		char modalias[40];
+
+		/* skip the holes */
+		if (!has_second_chip)
+			i *= 2;
+
+		nor = &q->nor[i];
+		mtd = &q->mtd[i];
+
+		nor->mtd = mtd;
+		nor->dev = dev;
+		nor->priv = q;
+		mtd->priv = nor;
+
+		/* fill the hooks */
+		nor->read_reg = fsl_qspi_read_reg;
+		nor->write_reg = fsl_qspi_write_reg;
+		nor->read = fsl_qspi_read;
+		nor->write = fsl_qspi_write;
+		nor->erase = fsl_qspi_erase;
+
+		nor->prepare = fsl_qspi_prep;
+		nor->unprepare = fsl_qspi_unprep;
+
+		if (of_modalias_node(np, modalias, sizeof(modalias)) < 0)
+			goto map_failed;
+
+		id = spi_nor_match_id(modalias);
+		if (!id)
+			goto map_failed;
+
+		ret = of_property_read_u32(np, "spi-max-frequency",
+				&q->clk_rate);
+		if (ret < 0)
+			goto map_failed;
+
+		/* set the chip address for READID */
+		fsl_qspi_set_base_addr(q, nor);
+
+		ret = spi_nor_scan(nor, id, SPI_NOR_QUAD);
+		if (ret)
+			goto map_failed;
+
+		ppdata.of_node = np;
+		ret = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
+		if (ret)
+			goto map_failed;
+
+		/* Set the correct NOR size now. */
+		if (q->nor_size == 0) {
+			q->nor_size = mtd->size;
+
+			/* Map the SPI NOR to accessiable address */
+			fsl_qspi_set_map_addr(q);
+		}
+
+		/*
+		 * The TX FIFO is 64 bytes in the Vybrid, but the Page Program
+		 * may writes 265 bytes per time. The write is working in the
+		 * unit of the TX FIFO, not in the unit of the SPI NOR's page
+		 * size.
+		 *
+		 * So shrink the spi_nor->page_size if it is larger then the
+		 * TX FIFO.
+		 */
+		if (nor->page_size > q->devtype_data->txfifo)
+			nor->page_size = q->devtype_data->txfifo;
+
+		i++;
+	}
+
+	/* finish the rest init. */
+	ret = fsl_qspi_nor_setup_last(q);
+	if (ret)
+		goto last_init_failed;
+
+	clk_disable(q->clk);
+	clk_disable(q->clk_en);
+	dev_info(dev, "QuadSPI SPI NOR flash driver\n");
+	return 0;
+
+last_init_failed:
+	for (i = 0; i < q->nor_num; i++)
+		mtd_device_unregister(&q->mtd[i]);
+
+irq_failed:
+	clk_disable_unprepare(q->clk);
+	clk_disable_unprepare(q->clk_en);
+map_failed:
+	dev_err(dev, "Freescale QuadSPI probe failed\n");
+	return ret;
+}
+
+static int fsl_qspi_remove(struct platform_device *pdev)
+{
+	struct fsl_qspi *q = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < q->nor_num; i++)
+		mtd_device_unregister(&q->mtd[i]);
+
+	/* disable the hardware */
+	writel(QUADSPI_MCR_MDIS_MASK, q->iobase + QUADSPI_MCR);
+	writel(0x0, q->iobase + QUADSPI_RSER);
+
+	clk_unprepare(q->clk);
+	clk_unprepare(q->clk_en);
+	return 0;
+}
+
+static struct platform_driver fsl_qspi_driver = {
+	.driver = {
+		.name	= "fsl-quadspi",
+		.bus	= &platform_bus_type,
+		.owner	= THIS_MODULE,
+		.of_match_table = fsl_qspi_dt_ids,
+	},
+	.probe          = fsl_qspi_probe,
+	.remove		= fsl_qspi_remove,
+};
+module_platform_driver(fsl_qspi_driver);
+
+MODULE_DESCRIPTION("Freescale QuadSPI Controller Driver");
+MODULE_AUTHOR("Freescale Semiconductor Inc.");
+MODULE_LICENSE("GPL v2");
--- /dev/null
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -0,0 +1,17 @@
+menuconfig MTD_SPI_NOR
+	tristate "SPI-NOR device support"
+	depends on MTD
+	help
+	  This is the framework for the SPI NOR which can be used by the SPI
+	  device drivers and the SPI-NOR device driver.
+
+if MTD_SPI_NOR
+
+config SPI_FSL_QUADSPI
+	tristate "Freescale Quad SPI controller"
+	depends on ARCH_MXC
+	help
+	  This enables support for the Quad SPI controller in master mode.
+	  We only connect the NOR to this controller now.
+
+endif # MTD_SPI_NOR
--- /dev/null
+++ b/drivers/mtd/spi-nor/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
+obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
--- /dev/null
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -0,0 +1,1160 @@
+/*
+ * Based on m25p80.c, by Mike Lavender (mike@steroidmicros.com), with
+ * influence from lart.c (Abraham Van Der Merwe) and mtd_dataflash.c
+ *
+ * Copyright (C) 2005, Intec Automation Inc.
+ * Copyright (C) 2014, Freescale Semiconductor, Inc.
+ *
+ * This code 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.
+ */
+
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/math64.h>
+
+#include <linux/mtd/cfi.h>
+#include <linux/mtd/mtd.h>
+#include <linux/of_platform.h>
+#include <linux/spi/flash.h>
+#include <linux/mtd/spi-nor.h>
+
+/* Define max times to check status register before we give up. */
+#define	MAX_READY_WAIT_JIFFIES	(40 * HZ) /* M25P16 specs 40s max chip erase */
+
+#define JEDEC_MFR(_jedec_id)	((_jedec_id) >> 16)
+
+/*
+ * Read the status register, returning its value in the location
+ * Return the status register value.
+ * Returns negative if error occurred.
+ */
+static int read_sr(struct spi_nor *nor)
+{
+	int ret;
+	u8 val;
+
+	ret = nor->read_reg(nor, SPINOR_OP_RDSR, &val, 1);
+	if (ret < 0) {
+		pr_err("error %d reading SR\n", (int) ret);
+		return ret;
+	}
+
+	return val;
+}
+
+/*
+ * Read the flag status register, returning its value in the location
+ * Return the status register value.
+ * Returns negative if error occurred.
+ */
+static int read_fsr(struct spi_nor *nor)
+{
+	int ret;
+	u8 val;
+
+	ret = nor->read_reg(nor, SPINOR_OP_RDFSR, &val, 1);
+	if (ret < 0) {
+		pr_err("error %d reading FSR\n", ret);
+		return ret;
+	}
+
+	return val;
+}
+
+/*
+ * Read configuration register, returning its value in the
+ * location. Return the configuration register value.
+ * Returns negative if error occured.
+ */
+static int read_cr(struct spi_nor *nor)
+{
+	int ret;
+	u8 val;
+
+	ret = nor->read_reg(nor, SPINOR_OP_RDCR, &val, 1);
+	if (ret < 0) {
+		dev_err(nor->dev, "error %d reading CR\n", ret);
+		return ret;
+	}
+
+	return val;
+}
+
+/*
+ * Dummy Cycle calculation for different type of read.
+ * It can be used to support more commands with
+ * different dummy cycle requirements.
+ */
+static inline int spi_nor_read_dummy_cycles(struct spi_nor *nor)
+{
+	switch (nor->flash_read) {
+	case SPI_NOR_FAST:
+	case SPI_NOR_DUAL:
+	case SPI_NOR_QUAD:
+		return 1;
+	case SPI_NOR_NORMAL:
+		return 0;
+	}
+	return 0;
+}
+
+/*
+ * Write status register 1 byte
+ * Returns negative if error occurred.
+ */
+static inline int write_sr(struct spi_nor *nor, u8 val)
+{
+	nor->cmd_buf[0] = val;
+	return nor->write_reg(nor, SPINOR_OP_WRSR, nor->cmd_buf, 1, 0);
+}
+
+/*
+ * Set write enable latch with Write Enable command.
+ * Returns negative if error occurred.
+ */
+static inline int write_enable(struct spi_nor *nor)
+{
+	return nor->write_reg(nor, SPINOR_OP_WREN, NULL, 0, 0);
+}
+
+/*
+ * Send write disble instruction to the chip.
+ */
+static inline int write_disable(struct spi_nor *nor)
+{
+	return nor->write_reg(nor, SPINOR_OP_WRDI, NULL, 0, 0);
+}
+
+static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
+{
+	return mtd->priv;
+}
+
+/* Enable/disable 4-byte addressing mode. */
+static inline int set_4byte(struct spi_nor *nor, u32 jedec_id, int enable)
+{
+	int status;
+	bool need_wren = false;
+	u8 cmd;
+
+	switch (JEDEC_MFR(jedec_id)) {
+	case CFI_MFR_ST: /* Micron, actually */
+		/* Some Micron need WREN command; all will accept it */
+		need_wren = true;
+	case CFI_MFR_MACRONIX:
+	case 0xEF /* winbond */:
+		if (need_wren)
+			write_enable(nor);
+
+		cmd = enable ? SPINOR_OP_EN4B : SPINOR_OP_EX4B;
+		status = nor->write_reg(nor, cmd, NULL, 0, 0);
+		if (need_wren)
+			write_disable(nor);
+
+		return status;
+	default:
+		/* Spansion style */
+		nor->cmd_buf[0] = enable << 7;
+		return nor->write_reg(nor, SPINOR_OP_BRWR, nor->cmd_buf, 1, 0);
+	}
+}
+
+static int spi_nor_wait_till_ready(struct spi_nor *nor)
+{
+	unsigned long deadline;
+	int sr;
+
+	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
+
+	do {
+		cond_resched();
+
+		sr = read_sr(nor);
+		if (sr < 0)
+			break;
+		else if (!(sr & SR_WIP))
+			return 0;
+	} while (!time_after_eq(jiffies, deadline));
+
+	return -ETIMEDOUT;
+}
+
+static int spi_nor_wait_till_fsr_ready(struct spi_nor *nor)
+{
+	unsigned long deadline;
+	int sr;
+	int fsr;
+
+	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
+
+	do {
+		cond_resched();
+
+		sr = read_sr(nor);
+		if (sr < 0) {
+			break;
+		} else if (!(sr & SR_WIP)) {
+			fsr = read_fsr(nor);
+			if (fsr < 0)
+				break;
+			if (fsr & FSR_READY)
+				return 0;
+		}
+	} while (!time_after_eq(jiffies, deadline));
+
+	return -ETIMEDOUT;
+}
+
+/*
+ * Service routine to read status register until ready, or timeout occurs.
+ * Returns non-zero if error.
+ */
+static int wait_till_ready(struct spi_nor *nor)
+{
+	return nor->wait_till_ready(nor);
+}
+
+/*
+ * Erase the whole flash memory
+ *
+ * Returns 0 if successful, non-zero otherwise.
+ */
+static int erase_chip(struct spi_nor *nor)
+{
+	int ret;
+
+	dev_dbg(nor->dev, " %lldKiB\n", (long long)(nor->mtd->size >> 10));
+
+	/* Wait until finished previous write command. */
+	ret = wait_till_ready(nor);
+	if (ret)
+		return ret;
+
+	/* Send write enable, then erase commands. */
+	write_enable(nor);
+
+	return nor->write_reg(nor, SPINOR_OP_CHIP_ERASE, NULL, 0, 0);
+}
+
+static int spi_nor_lock_and_prep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+	int ret = 0;
+
+	mutex_lock(&nor->lock);
+
+	if (nor->prepare) {
+		ret = nor->prepare(nor, ops);
+		if (ret) {
+			dev_err(nor->dev, "failed in the preparation.\n");
+			mutex_unlock(&nor->lock);
+			return ret;
+		}
+	}
+	return ret;
+}
+
+static void spi_nor_unlock_and_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
+{
+	if (nor->unprepare)
+		nor->unprepare(nor, ops);
+	mutex_unlock(&nor->lock);
+}
+
+/*
+ * Erase an address range on the nor chip.  The address range may extend
+ * one or more erase sectors.  Return an error is there is a problem erasing.
+ */
+static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+	struct spi_nor *nor = mtd_to_spi_nor(mtd);
+	u32 addr, len;
+	uint32_t rem;
+	int ret;
+
+	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
+			(long long)instr->len);
+
+	div_u64_rem(instr->len, mtd->erasesize, &rem);
+	if (rem)
+		return -EINVAL;
+
+	addr = instr->addr;
+	len = instr->len;
+
+	ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_ERASE);
+	if (ret)
+		return ret;
+
+	/* whole-chip erase? */
+	if (len == mtd->size) {
+		if (erase_chip(nor)) {
+			ret = -EIO;
+			goto erase_err;
+		}
+
+	/* REVISIT in some cases we could speed up erasing large regions
+	 * by using SPINOR_OP_SE instead of SPINOR_OP_BE_4K.  We may have set up
+	 * to use "small sector erase", but that's not always optimal.
+	 */
+
+	/* "sector"-at-a-time erase */
+	} else {
+		while (len) {
+			if (nor->erase(nor, addr)) {
+				ret = -EIO;
+				goto erase_err;
+			}
+
+			addr += mtd->erasesize;
+			len -= mtd->erasesize;
+		}
+	}
+
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_ERASE);
+
+	instr->state = MTD_ERASE_DONE;
+	mtd_erase_callback(instr);
+
+	return ret;
+
+erase_err:
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_ERASE);
+	instr->state = MTD_ERASE_FAILED;
+	return ret;
+}
+
+static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+	struct spi_nor *nor = mtd_to_spi_nor(mtd);
+	uint32_t offset = ofs;
+	uint8_t status_old, status_new;
+	int ret = 0;
+
+	ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_LOCK);
+	if (ret)
+		return ret;
+
+	/* Wait until finished previous command */
+	ret = wait_till_ready(nor);
+	if (ret)
+		goto err;
+
+	status_old = read_sr(nor);
+
+	if (offset < mtd->size - (mtd->size / 2))
+		status_new = status_old | SR_BP2 | SR_BP1 | SR_BP0;
+	else if (offset < mtd->size - (mtd->size / 4))
+		status_new = (status_old & ~SR_BP0) | SR_BP2 | SR_BP1;
+	else if (offset < mtd->size - (mtd->size / 8))
+		status_new = (status_old & ~SR_BP1) | SR_BP2 | SR_BP0;
+	else if (offset < mtd->size - (mtd->size / 16))
+		status_new = (status_old & ~(SR_BP0 | SR_BP1)) | SR_BP2;
+	else if (offset < mtd->size - (mtd->size / 32))
+		status_new = (status_old & ~SR_BP2) | SR_BP1 | SR_BP0;
+	else if (offset < mtd->size - (mtd->size / 64))
+		status_new = (status_old & ~(SR_BP2 | SR_BP0)) | SR_BP1;
+	else
+		status_new = (status_old & ~(SR_BP2 | SR_BP1)) | SR_BP0;
+
+	/* Only modify protection if it will not unlock other areas */
+	if ((status_new & (SR_BP2 | SR_BP1 | SR_BP0)) >
+				(status_old & (SR_BP2 | SR_BP1 | SR_BP0))) {
+		write_enable(nor);
+		ret = write_sr(nor, status_new);
+		if (ret)
+			goto err;
+	}
+
+err:
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_LOCK);
+	return ret;
+}
+
+static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+	struct spi_nor *nor = mtd_to_spi_nor(mtd);
+	uint32_t offset = ofs;
+	uint8_t status_old, status_new;
+	int ret = 0;
+
+	ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_UNLOCK);
+	if (ret)
+		return ret;
+
+	/* Wait until finished previous command */
+	ret = wait_till_ready(nor);
+	if (ret)
+		goto err;
+
+	status_old = read_sr(nor);
+
+	if (offset+len > mtd->size - (mtd->size / 64))
+		status_new = status_old & ~(SR_BP2 | SR_BP1 | SR_BP0);
+	else if (offset+len > mtd->size - (mtd->size / 32))
+		status_new = (status_old & ~(SR_BP2 | SR_BP1)) | SR_BP0;
+	else if (offset+len > mtd->size - (mtd->size / 16))
+		status_new = (status_old & ~(SR_BP2 | SR_BP0)) | SR_BP1;
+	else if (offset+len > mtd->size - (mtd->size / 8))
+		status_new = (status_old & ~SR_BP2) | SR_BP1 | SR_BP0;
+	else if (offset+len > mtd->size - (mtd->size / 4))
+		status_new = (status_old & ~(SR_BP0 | SR_BP1)) | SR_BP2;
+	else if (offset+len > mtd->size - (mtd->size / 2))
+		status_new = (status_old & ~SR_BP1) | SR_BP2 | SR_BP0;
+	else
+		status_new = (status_old & ~SR_BP0) | SR_BP2 | SR_BP1;
+
+	/* Only modify protection if it will not lock other areas */
+	if ((status_new & (SR_BP2 | SR_BP1 | SR_BP0)) <
+				(status_old & (SR_BP2 | SR_BP1 | SR_BP0))) {
+		write_enable(nor);
+		ret = write_sr(nor, status_new);
+		if (ret)
+			goto err;
+	}
+
+err:
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_UNLOCK);
+	return ret;
+}
+
+struct flash_info {
+	/* JEDEC id zero means "no ID" (most older chips); otherwise it has
+	 * a high byte of zero plus three data bytes: the manufacturer id,
+	 * then a two byte device id.
+	 */
+	u32		jedec_id;
+	u16             ext_id;
+
+	/* The size listed here is what works with SPINOR_OP_SE, which isn't
+	 * necessarily called a "sector" by the vendor.
+	 */
+	unsigned	sector_size;
+	u16		n_sectors;
+
+	u16		page_size;
+	u16		addr_width;
+
+	u16		flags;
+#define	SECT_4K			0x01	/* SPINOR_OP_BE_4K works uniformly */
+#define	SPI_NOR_NO_ERASE	0x02	/* No erase command needed */
+#define	SST_WRITE		0x04	/* use SST byte programming */
+#define	SPI_NOR_NO_FR		0x08	/* Can't do fastread */
+#define	SECT_4K_PMC		0x10	/* SPINOR_OP_BE_4K_PMC works uniformly */
+#define	SPI_NOR_DUAL_READ	0x20    /* Flash supports Dual Read */
+#define	SPI_NOR_QUAD_READ	0x40    /* Flash supports Quad Read */
+#define	USE_FSR			0x80	/* use flag status register */
+};
+
+#define INFO(_jedec_id, _ext_id, _sector_size, _n_sectors, _flags)	\
+	((kernel_ulong_t)&(struct flash_info) {				\
+		.jedec_id = (_jedec_id),				\
+		.ext_id = (_ext_id),					\
+		.sector_size = (_sector_size),				\
+		.n_sectors = (_n_sectors),				\
+		.page_size = 256,					\
+		.flags = (_flags),					\
+	})
+
+#define CAT25_INFO(_sector_size, _n_sectors, _page_size, _addr_width, _flags)	\
+	((kernel_ulong_t)&(struct flash_info) {				\
+		.sector_size = (_sector_size),				\
+		.n_sectors = (_n_sectors),				\
+		.page_size = (_page_size),				\
+		.addr_width = (_addr_width),				\
+		.flags = (_flags),					\
+	})
+
+/* NOTE: double check command sets and memory organization when you add
+ * more nor chips.  This current list focusses on newer chips, which
+ * have been converging on command sets which including JEDEC ID.
+ */
+const struct spi_device_id spi_nor_ids[] = {
+	/* Atmel -- some are (confusingly) marketed as "DataFlash" */
+	{ "at25fs010",  INFO(0x1f6601, 0, 32 * 1024,   4, SECT_4K) },
+	{ "at25fs040",  INFO(0x1f6604, 0, 64 * 1024,   8, SECT_4K) },
+
+	{ "at25df041a", INFO(0x1f4401, 0, 64 * 1024,   8, SECT_4K) },
+	{ "at25df321a", INFO(0x1f4701, 0, 64 * 1024,  64, SECT_4K) },
+	{ "at25df641",  INFO(0x1f4800, 0, 64 * 1024, 128, SECT_4K) },
+
+	{ "at26f004",   INFO(0x1f0400, 0, 64 * 1024,  8, SECT_4K) },
+	{ "at26df081a", INFO(0x1f4501, 0, 64 * 1024, 16, SECT_4K) },
+	{ "at26df161a", INFO(0x1f4601, 0, 64 * 1024, 32, SECT_4K) },
+	{ "at26df321",  INFO(0x1f4700, 0, 64 * 1024, 64, SECT_4K) },
+
+	{ "at45db081d", INFO(0x1f2500, 0, 64 * 1024, 16, SECT_4K) },
+
+	/* EON -- en25xxx */
+	{ "en25f32",    INFO(0x1c3116, 0, 64 * 1024,   64, SECT_4K) },
+	{ "en25p32",    INFO(0x1c2016, 0, 64 * 1024,   64, 0) },
+	{ "en25q32b",   INFO(0x1c3016, 0, 64 * 1024,   64, 0) },
+	{ "en25p64",    INFO(0x1c2017, 0, 64 * 1024,  128, 0) },
+	{ "en25q64",    INFO(0x1c3017, 0, 64 * 1024,  128, SECT_4K) },
+	{ "en25qh128",  INFO(0x1c7018, 0, 64 * 1024,  256, 0) },
+	{ "en25qh256",  INFO(0x1c7019, 0, 64 * 1024,  512, 0) },
+
+	/* ESMT */
+	{ "f25l32pa", INFO(0x8c2016, 0, 64 * 1024, 64, SECT_4K) },
+
+	/* Everspin */
+	{ "mr25h256", CAT25_INFO( 32 * 1024, 1, 256, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+	{ "mr25h10",  CAT25_INFO(128 * 1024, 1, 256, 3, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+
+	/* GigaDevice */
+	{ "gd25q32", INFO(0xc84016, 0, 64 * 1024,  64, SECT_4K) },
+	{ "gd25q64", INFO(0xc84017, 0, 64 * 1024, 128, SECT_4K) },
+
+	/* Intel/Numonyx -- xxxs33b */
+	{ "160s33b",  INFO(0x898911, 0, 64 * 1024,  32, 0) },
+	{ "320s33b",  INFO(0x898912, 0, 64 * 1024,  64, 0) },
+	{ "640s33b",  INFO(0x898913, 0, 64 * 1024, 128, 0) },
+
+	/* Macronix */
+	{ "mx25l2005a",  INFO(0xc22012, 0, 64 * 1024,   4, SECT_4K) },
+	{ "mx25l4005a",  INFO(0xc22013, 0, 64 * 1024,   8, SECT_4K) },
+	{ "mx25l8005",   INFO(0xc22014, 0, 64 * 1024,  16, 0) },
+	{ "mx25l1606e",  INFO(0xc22015, 0, 64 * 1024,  32, SECT_4K) },
+	{ "mx25l3205d",  INFO(0xc22016, 0, 64 * 1024,  64, 0) },
+	{ "mx25l3255e",  INFO(0xc29e16, 0, 64 * 1024,  64, SECT_4K) },
+	{ "mx25l6405d",  INFO(0xc22017, 0, 64 * 1024, 128, 0) },
+	{ "mx25l12805d", INFO(0xc22018, 0, 64 * 1024, 256, 0) },
+	{ "mx25l12855e", INFO(0xc22618, 0, 64 * 1024, 256, 0) },
+	{ "mx25l25635e", INFO(0xc22019, 0, 64 * 1024, 512, 0) },
+	{ "mx25l25655e", INFO(0xc22619, 0, 64 * 1024, 512, 0) },
+	{ "mx66l51235l", INFO(0xc2201a, 0, 64 * 1024, 1024, SPI_NOR_QUAD_READ) },
+	{ "mx66l1g55g",  INFO(0xc2261b, 0, 64 * 1024, 2048, SPI_NOR_QUAD_READ) },
+
+	/* Micron */
+	{ "n25q064",     INFO(0x20ba17, 0, 64 * 1024,  128, 0) },
+	{ "n25q128a11",  INFO(0x20bb18, 0, 64 * 1024,  256, 0) },
+	{ "n25q128a13",  INFO(0x20ba18, 0, 64 * 1024,  256, 0) },
+	{ "n25q256a",    INFO(0x20ba19, 0, 64 * 1024,  512, SECT_4K) },
+	{ "n25q512a",    INFO(0x20bb20, 0, 64 * 1024, 1024, SECT_4K) },
+	{ "n25q512ax3",  INFO(0x20ba20, 0, 64 * 1024, 1024, USE_FSR) },
+	{ "n25q00",      INFO(0x20ba21, 0, 64 * 1024, 2048, USE_FSR) },
+
+	/* PMC */
+	{ "pm25lv512",   INFO(0,        0, 32 * 1024,    2, SECT_4K_PMC) },
+	{ "pm25lv010",   INFO(0,        0, 32 * 1024,    4, SECT_4K_PMC) },
+	{ "pm25lq032",   INFO(0x7f9d46, 0, 64 * 1024,   64, SECT_4K) },
+
+	/* Spansion -- single (large) sector size only, at least
+	 * for the chips listed here (without boot sectors).
+	 */
+	{ "s25sl032p",  INFO(0x010215, 0x4d00,  64 * 1024,  64, SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
+	{ "s25sl064p",  INFO(0x010216, 0x4d00,  64 * 1024, 128, 0) },
+	{ "s25fl256s0", INFO(0x010219, 0x4d00, 256 * 1024, 128, 0) },
+	{ "s25fl256s1", INFO(0x010219, 0x4d01,  64 * 1024, 512, SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
+	{ "s25fl512s",  INFO(0x010220, 0x4d00, 256 * 1024, 256, SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) },
+	{ "s70fl01gs",  INFO(0x010221, 0x4d00, 256 * 1024, 256, 0) },
+	{ "s25sl12800", INFO(0x012018, 0x0300, 256 * 1024,  64, 0) },
+	{ "s25sl12801", INFO(0x012018, 0x0301,  64 * 1024, 256, 0) },
+	{ "s25fl129p0", INFO(0x012018, 0x4d00, 256 * 1024,  64, 0) },
+	{ "s25fl129p1", INFO(0x012018, 0x4d01,  64 * 1024, 256, 0) },
+	{ "s25sl004a",  INFO(0x010212,      0,  64 * 1024,   8, 0) },
+	{ "s25sl008a",  INFO(0x010213,      0,  64 * 1024,  16, 0) },
+	{ "s25sl016a",  INFO(0x010214,      0,  64 * 1024,  32, 0) },
+	{ "s25sl032a",  INFO(0x010215,      0,  64 * 1024,  64, 0) },
+	{ "s25sl064a",  INFO(0x010216,      0,  64 * 1024, 128, 0) },
+	{ "s25fl008k",  INFO(0xef4014,      0,  64 * 1024,  16, SECT_4K) },
+	{ "s25fl016k",  INFO(0xef4015,      0,  64 * 1024,  32, SECT_4K) },
+	{ "s25fl064k",  INFO(0xef4017,      0,  64 * 1024, 128, SECT_4K) },
+
+	/* SST -- large erase sizes are "overlays", "sectors" are 4K */
+	{ "sst25vf040b", INFO(0xbf258d, 0, 64 * 1024,  8, SECT_4K | SST_WRITE) },
+	{ "sst25vf080b", INFO(0xbf258e, 0, 64 * 1024, 16, SECT_4K | SST_WRITE) },
+	{ "sst25vf016b", INFO(0xbf2541, 0, 64 * 1024, 32, SECT_4K | SST_WRITE) },
+	{ "sst25vf032b", INFO(0xbf254a, 0, 64 * 1024, 64, SECT_4K | SST_WRITE) },
+	{ "sst25vf064c", INFO(0xbf254b, 0, 64 * 1024, 128, SECT_4K) },
+	{ "sst25wf512",  INFO(0xbf2501, 0, 64 * 1024,  1, SECT_4K | SST_WRITE) },
+	{ "sst25wf010",  INFO(0xbf2502, 0, 64 * 1024,  2, SECT_4K | SST_WRITE) },
+	{ "sst25wf020",  INFO(0xbf2503, 0, 64 * 1024,  4, SECT_4K | SST_WRITE) },
+	{ "sst25wf040",  INFO(0xbf2504, 0, 64 * 1024,  8, SECT_4K | SST_WRITE) },
+
+	/* ST Microelectronics -- newer production may have feature updates */
+	{ "m25p05",  INFO(0x202010,  0,  32 * 1024,   2, 0) },
+	{ "m25p10",  INFO(0x202011,  0,  32 * 1024,   4, 0) },
+	{ "m25p20",  INFO(0x202012,  0,  64 * 1024,   4, 0) },
+	{ "m25p40",  INFO(0x202013,  0,  64 * 1024,   8, 0) },
+	{ "m25p80",  INFO(0x202014,  0,  64 * 1024,  16, 0) },
+	{ "m25p16",  INFO(0x202015,  0,  64 * 1024,  32, 0) },
+	{ "m25p32",  INFO(0x202016,  0,  64 * 1024,  64, 0) },
+	{ "m25p64",  INFO(0x202017,  0,  64 * 1024, 128, 0) },
+	{ "m25p128", INFO(0x202018,  0, 256 * 1024,  64, 0) },
+	{ "n25q032", INFO(0x20ba16,  0,  64 * 1024,  64, 0) },
+
+	{ "m25p05-nonjedec",  INFO(0, 0,  32 * 1024,   2, 0) },
+	{ "m25p10-nonjedec",  INFO(0, 0,  32 * 1024,   4, 0) },
+	{ "m25p20-nonjedec",  INFO(0, 0,  64 * 1024,   4, 0) },
+	{ "m25p40-nonjedec",  INFO(0, 0,  64 * 1024,   8, 0) },
+	{ "m25p80-nonjedec",  INFO(0, 0,  64 * 1024,  16, 0) },
+	{ "m25p16-nonjedec",  INFO(0, 0,  64 * 1024,  32, 0) },
+	{ "m25p32-nonjedec",  INFO(0, 0,  64 * 1024,  64, 0) },
+	{ "m25p64-nonjedec",  INFO(0, 0,  64 * 1024, 128, 0) },
+	{ "m25p128-nonjedec", INFO(0, 0, 256 * 1024,  64, 0) },
+
+	{ "m45pe10", INFO(0x204011,  0, 64 * 1024,    2, 0) },
+	{ "m45pe80", INFO(0x204014,  0, 64 * 1024,   16, 0) },
+	{ "m45pe16", INFO(0x204015,  0, 64 * 1024,   32, 0) },
+
+	{ "m25pe20", INFO(0x208012,  0, 64 * 1024,  4,       0) },
+	{ "m25pe80", INFO(0x208014,  0, 64 * 1024, 16,       0) },
+	{ "m25pe16", INFO(0x208015,  0, 64 * 1024, 32, SECT_4K) },
+
+	{ "m25px16",    INFO(0x207115,  0, 64 * 1024, 32, SECT_4K) },
+	{ "m25px32",    INFO(0x207116,  0, 64 * 1024, 64, SECT_4K) },
+	{ "m25px32-s0", INFO(0x207316,  0, 64 * 1024, 64, SECT_4K) },
+	{ "m25px32-s1", INFO(0x206316,  0, 64 * 1024, 64, SECT_4K) },
+	{ "m25px64",    INFO(0x207117,  0, 64 * 1024, 128, 0) },
+
+	/* Winbond -- w25x "blocks" are 64K, "sectors" are 4KiB */
+	{ "w25x10", INFO(0xef3011, 0, 64 * 1024,  2,  SECT_4K) },
+	{ "w25x20", INFO(0xef3012, 0, 64 * 1024,  4,  SECT_4K) },
+	{ "w25x40", INFO(0xef3013, 0, 64 * 1024,  8,  SECT_4K) },
+	{ "w25x80", INFO(0xef3014, 0, 64 * 1024,  16, SECT_4K) },
+	{ "w25x16", INFO(0xef3015, 0, 64 * 1024,  32, SECT_4K) },
+	{ "w25x32", INFO(0xef3016, 0, 64 * 1024,  64, SECT_4K) },
+	{ "w25q32", INFO(0xef4016, 0, 64 * 1024,  64, SECT_4K) },
+	{ "w25q32dw", INFO(0xef6016, 0, 64 * 1024,  64, SECT_4K) },
+	{ "w25x64", INFO(0xef3017, 0, 64 * 1024, 128, SECT_4K) },
+	{ "w25q64", INFO(0xef4017, 0, 64 * 1024, 128, SECT_4K) },
+	{ "w25q128", INFO(0xef4018, 0, 64 * 1024, 256, SECT_4K) },
+	{ "w25q80", INFO(0xef5014, 0, 64 * 1024,  16, SECT_4K) },
+	{ "w25q80bl", INFO(0xef4014, 0, 64 * 1024,  16, SECT_4K) },
+	{ "w25q128", INFO(0xef4018, 0, 64 * 1024, 256, SECT_4K) },
+	{ "w25q256", INFO(0xef4019, 0, 64 * 1024, 512, SECT_4K) },
+
+	/* Catalyst / On Semiconductor -- non-JEDEC */
+	{ "cat25c11", CAT25_INFO(  16, 8, 16, 1, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+	{ "cat25c03", CAT25_INFO(  32, 8, 16, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+	{ "cat25c09", CAT25_INFO( 128, 8, 32, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+	{ "cat25c17", CAT25_INFO( 256, 8, 32, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+	{ "cat25128", CAT25_INFO(2048, 8, 64, 2, SPI_NOR_NO_ERASE | SPI_NOR_NO_FR) },
+	{ },
+};
+EXPORT_SYMBOL_GPL(spi_nor_ids);
+
+static const struct spi_device_id *spi_nor_read_id(struct spi_nor *nor)
+{
+	int			tmp;
+	u8			id[5];
+	u32			jedec;
+	u16                     ext_jedec;
+	struct flash_info	*info;
+
+	tmp = nor->read_reg(nor, SPINOR_OP_RDID, id, 5);
+	if (tmp < 0) {
+		dev_dbg(nor->dev, " error %d reading JEDEC ID\n", tmp);
+		return ERR_PTR(tmp);
+	}
+	jedec = id[0];
+	jedec = jedec << 8;
+	jedec |= id[1];
+	jedec = jedec << 8;
+	jedec |= id[2];
+
+	ext_jedec = id[3] << 8 | id[4];
+
+	for (tmp = 0; tmp < ARRAY_SIZE(spi_nor_ids) - 1; tmp++) {
+		info = (void *)spi_nor_ids[tmp].driver_data;
+		if (info->jedec_id == jedec) {
+			if (info->ext_id == 0 || info->ext_id == ext_jedec)
+				return &spi_nor_ids[tmp];
+		}
+	}
+	dev_err(nor->dev, "unrecognized JEDEC id %06x\n", jedec);
+	return ERR_PTR(-ENODEV);
+}
+
+static const struct spi_device_id *jedec_probe(struct spi_nor *nor)
+{
+	return nor->read_id(nor);
+}
+
+static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
+			size_t *retlen, u_char *buf)
+{
+	struct spi_nor *nor = mtd_to_spi_nor(mtd);
+	int ret;
+
+	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
+
+	ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_READ);
+	if (ret)
+		return ret;
+
+	ret = nor->read(nor, from, len, retlen, buf);
+
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_READ);
+	return ret;
+}
+
+static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
+		size_t *retlen, const u_char *buf)
+{
+	struct spi_nor *nor = mtd_to_spi_nor(mtd);
+	size_t actual;
+	int ret;
+
+	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
+
+	ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_WRITE);
+	if (ret)
+		return ret;
+
+	/* Wait until finished previous write command. */
+	ret = wait_till_ready(nor);
+	if (ret)
+		goto time_out;
+
+	write_enable(nor);
+
+	nor->sst_write_second = false;
+
+	actual = to % 2;
+	/* Start write from odd address. */
+	if (actual) {
+		nor->program_opcode = SPINOR_OP_BP;
+
+		/* write one byte. */
+		nor->write(nor, to, 1, retlen, buf);
+		ret = wait_till_ready(nor);
+		if (ret)
+			goto time_out;
+	}
+	to += actual;
+
+	/* Write out most of the data here. */
+	for (; actual < len - 1; actual += 2) {
+		nor->program_opcode = SPINOR_OP_AAI_WP;
+
+		/* write two bytes. */
+		nor->write(nor, to, 2, retlen, buf + actual);
+		ret = wait_till_ready(nor);
+		if (ret)
+			goto time_out;
+		to += 2;
+		nor->sst_write_second = true;
+	}
+	nor->sst_write_second = false;
+
+	write_disable(nor);
+	ret = wait_till_ready(nor);
+	if (ret)
+		goto time_out;
+
+	/* Write out trailing byte if it exists. */
+	if (actual != len) {
+		write_enable(nor);
+
+		nor->program_opcode = SPINOR_OP_BP;
+		nor->write(nor, to, 1, retlen, buf + actual);
+
+		ret = wait_till_ready(nor);
+		if (ret)
+			goto time_out;
+		write_disable(nor);
+	}
+time_out:
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_WRITE);
+	return ret;
+}
+
+/*
+ * Write an address range to the nor chip.  Data must be written in
+ * FLASH_PAGESIZE chunks.  The address range may be any size provided
+ * it is within the physical boundaries.
+ */
+static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
+	size_t *retlen, const u_char *buf)
+{
+	struct spi_nor *nor = mtd_to_spi_nor(mtd);
+	u32 page_offset, page_size, i;
+	int ret;
+
+	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
+
+	ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_WRITE);
+	if (ret)
+		return ret;
+
+	/* Wait until finished previous write command. */
+	ret = wait_till_ready(nor);
+	if (ret)
+		goto write_err;
+
+	write_enable(nor);
+
+	page_offset = to & (nor->page_size - 1);
+
+	/* do all the bytes fit onto one page? */
+	if (page_offset + len <= nor->page_size) {
+		nor->write(nor, to, len, retlen, buf);
+	} else {
+		/* the size of data remaining on the first page */
+		page_size = nor->page_size - page_offset;
+		nor->write(nor, to, page_size, retlen, buf);
+
+		/* write everything in nor->page_size chunks */
+		for (i = page_size; i < len; i += page_size) {
+			page_size = len - i;
+			if (page_size > nor->page_size)
+				page_size = nor->page_size;
+
+			wait_till_ready(nor);
+			write_enable(nor);
+
+			nor->write(nor, to + i, page_size, retlen, buf + i);
+		}
+	}
+
+write_err:
+	spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_WRITE);
+	return 0;
+}
+
+static int macronix_quad_enable(struct spi_nor *nor)
+{
+	int ret, val;
+
+	val = read_sr(nor);
+	write_enable(nor);
+
+	nor->cmd_buf[0] = val | SR_QUAD_EN_MX;
+	nor->write_reg(nor, SPINOR_OP_WRSR, nor->cmd_buf, 1, 0);
+
+	if (wait_till_ready(nor))
+		return 1;
+
+	ret = read_sr(nor);
+	if (!(ret > 0 && (ret & SR_QUAD_EN_MX))) {
+		dev_err(nor->dev, "Macronix Quad bit not set\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * Write status Register and configuration register with 2 bytes
+ * The first byte will be written to the status register, while the
+ * second byte will be written to the configuration register.
+ * Return negative if error occured.
+ */
+static int write_sr_cr(struct spi_nor *nor, u16 val)
+{
+	nor->cmd_buf[0] = val & 0xff;
+	nor->cmd_buf[1] = (val >> 8);
+
+	return nor->write_reg(nor, SPINOR_OP_WRSR, nor->cmd_buf, 2, 0);
+}
+
+static int spansion_quad_enable(struct spi_nor *nor)
+{
+	int ret;
+	int quad_en = CR_QUAD_EN_SPAN << 8;
+
+	write_enable(nor);
+
+	ret = write_sr_cr(nor, quad_en);
+	if (ret < 0) {
+		dev_err(nor->dev,
+			"error while writing configuration register\n");
+		return -EINVAL;
+	}
+
+	/* read back and check it */
+	ret = read_cr(nor);
+	if (!(ret > 0 && (ret & CR_QUAD_EN_SPAN))) {
+		dev_err(nor->dev, "Spansion Quad bit not set\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int set_quad_mode(struct spi_nor *nor, u32 jedec_id)
+{
+	int status;
+
+	switch (JEDEC_MFR(jedec_id)) {
+	case CFI_MFR_MACRONIX:
+		status = macronix_quad_enable(nor);
+		if (status) {
+			dev_err(nor->dev, "Macronix quad-read not enabled\n");
+			return -EINVAL;
+		}
+		return status;
+	default:
+		status = spansion_quad_enable(nor);
+		if (status) {
+			dev_err(nor->dev, "Spansion quad-read not enabled\n");
+			return -EINVAL;
+		}
+		return status;
+	}
+}
+
+static int spi_nor_check(struct spi_nor *nor)
+{
+	if (!nor->dev || !nor->read || !nor->write ||
+		!nor->read_reg || !nor->write_reg || !nor->erase) {
+		pr_err("spi-nor: please fill all the necessary fields!\n");
+		return -EINVAL;
+	}
+
+	if (!nor->read_id)
+		nor->read_id = spi_nor_read_id;
+	if (!nor->wait_till_ready)
+		nor->wait_till_ready = spi_nor_wait_till_ready;
+
+	return 0;
+}
+
+int spi_nor_scan(struct spi_nor *nor, const struct spi_device_id *id,
+			enum read_mode mode)
+{
+	struct flash_info		*info;
+	struct flash_platform_data	*data;
+	struct device *dev = nor->dev;
+	struct mtd_info *mtd = nor->mtd;
+	struct device_node *np = dev->of_node;
+	int ret;
+	int i;
+
+	ret = spi_nor_check(nor);
+	if (ret)
+		return ret;
+
+	/* Platform data helps sort out which chip type we have, as
+	 * well as how this board partitions it.  If we don't have
+	 * a chip ID, try the JEDEC id commands; they'll work for most
+	 * newer chips, even if we don't recognize the particular chip.
+	 */
+	data = dev_get_platdata(dev);
+	if (data && data->type) {
+		const struct spi_device_id *plat_id;
+
+		for (i = 0; i < ARRAY_SIZE(spi_nor_ids) - 1; i++) {
+			plat_id = &spi_nor_ids[i];
+			if (strcmp(data->type, plat_id->name))
+				continue;
+			break;
+		}
+
+		if (i < ARRAY_SIZE(spi_nor_ids) - 1)
+			id = plat_id;
+		else
+			dev_warn(dev, "unrecognized id %s\n", data->type);
+	}
+
+	info = (void *)id->driver_data;
+
+	if (info->jedec_id) {
+		const struct spi_device_id *jid;
+
+		jid = jedec_probe(nor);
+		if (IS_ERR(jid)) {
+			return PTR_ERR(jid);
+		} else if (jid != id) {
+			/*
+			 * JEDEC knows better, so overwrite platform ID. We
+			 * can't trust partitions any longer, but we'll let
+			 * mtd apply them anyway, since some partitions may be
+			 * marked read-only, and we don't want to lose that
+			 * information, even if it's not 100% accurate.
+			 */
+			dev_warn(dev, "found %s, expected %s\n",
+				 jid->name, id->name);
+			id = jid;
+			info = (void *)jid->driver_data;
+		}
+	}
+
+	mutex_init(&nor->lock);
+
+	/*
+	 * Atmel, SST and Intel/Numonyx serial nor tend to power
+	 * up with the software protection bits set
+	 */
+
+	if (JEDEC_MFR(info->jedec_id) == CFI_MFR_ATMEL ||
+	    JEDEC_MFR(info->jedec_id) == CFI_MFR_INTEL ||
+	    JEDEC_MFR(info->jedec_id) == CFI_MFR_SST) {
+		write_enable(nor);
+		write_sr(nor, 0);
+	}
+
+	if (data && data->name)
+		mtd->name = data->name;
+	else
+		mtd->name = dev_name(dev);
+
+	mtd->type = MTD_NORFLASH;
+	mtd->writesize = 1;
+	mtd->flags = MTD_CAP_NORFLASH;
+	mtd->size = info->sector_size * info->n_sectors;
+	mtd->_erase = spi_nor_erase;
+	mtd->_read = spi_nor_read;
+
+	/* nor protection support for STmicro chips */
+	if (JEDEC_MFR(info->jedec_id) == CFI_MFR_ST) {
+		mtd->_lock = spi_nor_lock;
+		mtd->_unlock = spi_nor_unlock;
+	}
+
+	/* sst nor chips use AAI word program */
+	if (info->flags & SST_WRITE)
+		mtd->_write = sst_write;
+	else
+		mtd->_write = spi_nor_write;
+
+	if ((info->flags & USE_FSR) &&
+	    nor->wait_till_ready == spi_nor_wait_till_ready)
+		nor->wait_till_ready = spi_nor_wait_till_fsr_ready;
+
+	/* prefer "small sector" erase if possible */
+	if (info->flags & SECT_4K) {
+		nor->erase_opcode = SPINOR_OP_BE_4K;
+		mtd->erasesize = 4096;
+	} else if (info->flags & SECT_4K_PMC) {
+		nor->erase_opcode = SPINOR_OP_BE_4K_PMC;
+		mtd->erasesize = 4096;
+	} else {
+		nor->erase_opcode = SPINOR_OP_SE;
+		mtd->erasesize = info->sector_size;
+	}
+
+	if (info->flags & SPI_NOR_NO_ERASE)
+		mtd->flags |= MTD_NO_ERASE;
+
+	mtd->dev.parent = dev;
+	nor->page_size = info->page_size;
+	mtd->writebufsize = nor->page_size;
+
+	if (np) {
+		/* If we were instantiated by DT, use it */
+		if (of_property_read_bool(np, "m25p,fast-read"))
+			nor->flash_read = SPI_NOR_FAST;
+		else
+			nor->flash_read = SPI_NOR_NORMAL;
+	} else {
+		/* If we weren't instantiated by DT, default to fast-read */
+		nor->flash_read = SPI_NOR_FAST;
+	}
+
+	/* Some devices cannot do fast-read, no matter what DT tells us */
+	if (info->flags & SPI_NOR_NO_FR)
+		nor->flash_read = SPI_NOR_NORMAL;
+
+	/* Quad/Dual-read mode takes precedence over fast/normal */
+	if (mode == SPI_NOR_QUAD && info->flags & SPI_NOR_QUAD_READ) {
+		ret = set_quad_mode(nor, info->jedec_id);
+		if (ret) {
+			dev_err(dev, "quad mode not supported\n");
+			return ret;
+		}
+		nor->flash_read = SPI_NOR_QUAD;
+	} else if (mode == SPI_NOR_DUAL && info->flags & SPI_NOR_DUAL_READ) {
+		nor->flash_read = SPI_NOR_DUAL;
+	}
+
+	/* Default commands */
+	switch (nor->flash_read) {
+	case SPI_NOR_QUAD:
+		nor->read_opcode = SPINOR_OP_READ_1_1_4;
+		break;
+	case SPI_NOR_DUAL:
+		nor->read_opcode = SPINOR_OP_READ_1_1_2;
+		break;
+	case SPI_NOR_FAST:
+		nor->read_opcode = SPINOR_OP_READ_FAST;
+		break;
+	case SPI_NOR_NORMAL:
+		nor->read_opcode = SPINOR_OP_READ;
+		break;
+	default:
+		dev_err(dev, "No Read opcode defined\n");
+		return -EINVAL;
+	}
+
+	nor->program_opcode = SPINOR_OP_PP;
+
+	if (info->addr_width)
+		nor->addr_width = info->addr_width;
+	else if (mtd->size > 0x1000000) {
+		/* enable 4-byte addressing if the device exceeds 16MiB */
+		nor->addr_width = 4;
+		if (JEDEC_MFR(info->jedec_id) == CFI_MFR_AMD) {
+			/* Dedicated 4-byte command set */
+			switch (nor->flash_read) {
+			case SPI_NOR_QUAD:
+				nor->read_opcode = SPINOR_OP_READ4_1_1_4;
+				break;
+			case SPI_NOR_DUAL:
+				nor->read_opcode = SPINOR_OP_READ4_1_1_2;
+				break;
+			case SPI_NOR_FAST:
+				nor->read_opcode = SPINOR_OP_READ4_FAST;
+				break;
+			case SPI_NOR_NORMAL:
+				nor->read_opcode = SPINOR_OP_READ4;
+				break;
+			}
+			nor->program_opcode = SPINOR_OP_PP_4B;
+			/* No small sector erase for 4-byte command set */
+			nor->erase_opcode = SPINOR_OP_SE_4B;
+			mtd->erasesize = info->sector_size;
+		} else
+			set_4byte(nor, info->jedec_id, 1);
+	} else {
+		nor->addr_width = 3;
+	}
+
+	nor->read_dummy = spi_nor_read_dummy_cycles(nor);
+
+	dev_info(dev, "%s (%lld Kbytes)\n", id->name,
+			(long long)mtd->size >> 10);
+
+	dev_dbg(dev,
+		"mtd .name = %s, .size = 0x%llx (%lldMiB), "
+		".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
+		mtd->name, (long long)mtd->size, (long long)(mtd->size >> 20),
+		mtd->erasesize, mtd->erasesize / 1024, mtd->numeraseregions);
+
+	if (mtd->numeraseregions)
+		for (i = 0; i < mtd->numeraseregions; i++)
+			dev_dbg(dev,
+				"mtd.eraseregions[%d] = { .offset = 0x%llx, "
+				".erasesize = 0x%.8x (%uKiB), "
+				".numblocks = %d }\n",
+				i, (long long)mtd->eraseregions[i].offset,
+				mtd->eraseregions[i].erasesize,
+				mtd->eraseregions[i].erasesize / 1024,
+				mtd->eraseregions[i].numblocks);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(spi_nor_scan);
+
+const struct spi_device_id *spi_nor_match_id(char *name)
+{
+	const struct spi_device_id *id = spi_nor_ids;
+
+	while (id->name[0]) {
+		if (!strcmp(name, id->name))
+			return id;
+		id++;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(spi_nor_match_id);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
+MODULE_AUTHOR("Mike Lavender");
+MODULE_DESCRIPTION("framework for SPI NOR");
--- /dev/null
+++ b/include/linux/mtd/spi-nor.h
@@ -0,0 +1,218 @@
+/*
+ * Copyright (C) 2014 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_MTD_SPI_NOR_H
+#define __LINUX_MTD_SPI_NOR_H
+
+/*
+ * 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_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 SPI) */
+#define SPINOR_OP_READ_1_1_4	0x6b	/* Read data bytes (Quad SPI) */
+#define SPINOR_OP_PP		0x02	/* Page program (up to 256 bytes) */
+#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_RDCR		0x35	/* Read configuration register */
+#define SPINOR_OP_RDFSR		0x70	/* Read flag status register */
+
+/* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
+#define SPINOR_OP_READ4		0x13	/* Read data bytes (low frequency) */
+#define SPINOR_OP_READ4_FAST	0x0c	/* Read data bytes (high frequency) */
+#define SPINOR_OP_READ4_1_1_2	0x3c	/* Read data bytes (Dual SPI) */
+#define SPINOR_OP_READ4_1_1_4	0x6c	/* Read data bytes (Quad SPI) */
+#define SPINOR_OP_PP_4B		0x12	/* Page program (up to 256 bytes) */
+#define SPINOR_OP_SE_4B		0xdc	/* Sector erase (usually 64KiB) */
+
+/* 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 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 */
+
+/* Status Register bits. */
+#define SR_WIP			1	/* Write in progress */
+#define SR_WEL			2	/* Write enable latch */
+/* meaning of other SR_* bits may differ between vendors */
+#define SR_BP0			4	/* Block protect 0 */
+#define SR_BP1			8	/* Block protect 1 */
+#define SR_BP2			0x10	/* Block protect 2 */
+#define SR_SRWD			0x80	/* SR write protect */
+
+#define SR_QUAD_EN_MX		0x40	/* Macronix Quad I/O */
+
+/* Flag Status Register bits */
+#define FSR_READY		0x80
+
+/* Configuration Register bits. */
+#define CR_QUAD_EN_SPAN		0x2	/* Spansion Quad I/O */
+
+enum read_mode {
+	SPI_NOR_NORMAL = 0,
+	SPI_NOR_FAST,
+	SPI_NOR_DUAL,
+	SPI_NOR_QUAD,
+};
+
+/**
+ * struct spi_nor_xfer_cfg - Structure for defining a Serial Flash transfer
+ * @wren:		command for "Write Enable", or 0x00 for not required
+ * @cmd:		command for operation
+ * @cmd_pins:		number of pins to send @cmd (1, 2, 4)
+ * @addr:		address for operation
+ * @addr_pins:		number of pins to send @addr (1, 2, 4)
+ * @addr_width:		number of address bytes
+ *			(3,4, or 0 for address not required)
+ * @mode:		mode data
+ * @mode_pins:		number of pins to send @mode (1, 2, 4)
+ * @mode_cycles:	number of mode cycles (0 for mode not required)
+ * @dummy_cycles:	number of dummy cycles (0 for dummy not required)
+ */
+struct spi_nor_xfer_cfg {
+	u8		wren;
+	u8		cmd;
+	u8		cmd_pins;
+	u32		addr;
+	u8		addr_pins;
+	u8		addr_width;
+	u8		mode;
+	u8		mode_pins;
+	u8		mode_cycles;
+	u8		dummy_cycles;
+};
+
+#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,
+};
+
+/**
+ * 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.
+ * @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
+ * @flash_read:		the mode of the read
+ * @sst_write_second:	used by the SST write operation
+ * @cfg:		used by the read_xfer/write_xfer
+ * @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_xfer:		[OPTIONAL] the read fundamental primitive
+ * @write_xfer:		[OPTIONAL] the writefundamental primitive
+ * @read_reg:		[DRIVER-SPECIFIC] read out the register
+ * @write_reg:		[DRIVER-SPECIFIC] write data to the register
+ * @read_id:		[REPLACEABLE] read out the ID data, and find
+ *			the proper spi_device_id
+ * @wait_till_ready:	[REPLACEABLE] wait till the NOR becomes ready
+ * @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
+ * @priv:		the private data
+ */
+struct spi_nor {
+	struct mtd_info		*mtd;
+	struct mutex		lock;
+	struct device		*dev;
+	u32			page_size;
+	u8			addr_width;
+	u8			erase_opcode;
+	u8			read_opcode;
+	u8			read_dummy;
+	u8			program_opcode;
+	enum read_mode		flash_read;
+	bool			sst_write_second;
+	struct spi_nor_xfer_cfg	cfg;
+	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_xfer)(struct spi_nor *nor, struct spi_nor_xfer_cfg *cfg,
+			 u8 *buf, size_t len);
+	int (*write_xfer)(struct spi_nor *nor, struct spi_nor_xfer_cfg *cfg,
+			  u8 *buf, size_t len);
+	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,
+			int write_enable);
+	const struct spi_device_id *(*read_id)(struct spi_nor *nor);
+	int (*wait_till_ready)(struct spi_nor *nor);
+
+	int (*read)(struct spi_nor *nor, loff_t from,
+			size_t len, size_t *retlen, u_char *read_buf);
+	void (*write)(struct spi_nor *nor, loff_t to,
+			size_t len, size_t *retlen, const u_char *write_buf);
+	int (*erase)(struct spi_nor *nor, loff_t offs);
+
+	void *priv;
+};
+
+/**
+ * spi_nor_scan() - scan the SPI NOR
+ * @nor:	the spi_nor structure
+ * @id:		the spi_device_id provided by the driver
+ * @mode:	the read mode supported by the driver
+ *
+ * The drivers can use this fuction 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{}.
+ *
+ * The board may assigns a spi_device_id with @id which be used to compared with
+ * the spi_device_id detected by the scanning.
+ *
+ * Return: 0 for success, others for failure.
+ */
+int spi_nor_scan(struct spi_nor *nor, const struct spi_device_id *id,
+			enum read_mode mode);
+extern const struct spi_device_id spi_nor_ids[];
+
+/**
+ * spi_nor_match_id() - find the spi_device_id by the name
+ * @name:	the name of the spi_device_id
+ *
+ * The drivers use this function to find the spi_device_id
+ * specified by the @name.
+ *
+ * Return: returns the right spi_device_id pointer on success,
+ *         and returns NULL on failure.
+ */
+const struct spi_device_id *spi_nor_match_id(char *name);
+
+#endif