mtd: m25p80: use the SPI nor framework

Linux-MTD Mailing List linux-mtd at lists.infradead.org
Tue Jun 10 23:59:03 PDT 2014


Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=03e296f613affcc2671c1e86d8c25ecad867204e
Commit:     03e296f613affcc2671c1e86d8c25ecad867204e
Parent:     1ef391084b22d75110171d34f565f57e4be9b2a6
Author:     Brian Norris <computersforpeace at gmail.com>
AuthorDate: Thu Mar 20 05:00:12 2014 -0700
Committer:  Brian Norris <computersforpeace at gmail.com>
CommitDate: Mon Apr 14 11:22:58 2014 -0700

    mtd: m25p80: use the SPI nor framework
    
    Use the new SPI nor framework, and rewrite the m25p80:
     (0) remove all the NOR comands.
     (1) change the m25p->command to an array.
     (2) implement the necessary hooks, such as m25p80_read/m25p80_write.
    
    Tested with the m25p32.
    Signed-off-by: Huang Shijie <b32955 at freescale.com>
    Acked-by: Marek Vasut <marex at denx.de>
    [Brian: rebased]
    Signed-off-by: Brian Norris <computersforpeace at gmail.com>
---
 drivers/mtd/devices/Kconfig  |    2 +-
 drivers/mtd/devices/m25p80.c | 1623 +++++++-----------------------------------
 2 files changed, 266 insertions(+), 1359 deletions(-)

diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
index 1210bc2..48aa1aa 100644
--- a/drivers/mtd/devices/Kconfig
+++ b/drivers/mtd/devices/Kconfig
@@ -80,7 +80,7 @@ config MTD_DATAFLASH_OTP
 
 config MTD_M25P80
 	tristate "Support most SPI Flash chips (AT26DF, M25P, W25X, ...)"
-	depends on SPI_MASTER
+	depends on SPI_MASTER && MTD_SPI_NOR_BASE
 	help
 	  This enables access to most modern SPI flash chips, used for
 	  program and data storage.   Series supported include Atmel AT26DF,
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
dissimilarity index 92%
index 524dab3..4af6400 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -1,1358 +1,265 @@
-/*
- * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
- *
- * Author: Mike Lavender, mike at steroidmicros.com
- *
- * Copyright (c) 2005, Intec Automation Inc.
- *
- * Some parts are based on lart.c by Abraham Van Der Merwe
- *
- * Cleaned up and generalized based on mtd_dataflash.c
- *
- * 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/interrupt.h>
-#include <linux/mutex.h>
-#include <linux/math64.h>
-#include <linux/slab.h>
-#include <linux/sched.h>
-#include <linux/mod_devicetable.h>
-
-#include <linux/mtd/cfi.h>
-#include <linux/mtd/mtd.h>
-#include <linux/mtd/partitions.h>
-#include <linux/of_platform.h>
-
-#include <linux/spi/spi.h>
-#include <linux/spi/flash.h>
-
-/* Flash opcodes. */
-#define	OPCODE_WREN		0x06	/* Write enable */
-#define	OPCODE_RDSR		0x05	/* Read status register */
-#define	OPCODE_WRSR		0x01	/* Write status register 1 byte */
-#define	OPCODE_NORM_READ	0x03	/* Read data bytes (low frequency) */
-#define	OPCODE_FAST_READ	0x0b	/* Read data bytes (high frequency) */
-#define	OPCODE_DUAL_READ        0x3b    /* Read data bytes (Dual SPI) */
-#define	OPCODE_QUAD_READ        0x6b    /* Read data bytes (Quad SPI) */
-#define	OPCODE_PP		0x02	/* Page program (up to 256 bytes) */
-#define	OPCODE_BE_4K		0x20	/* Erase 4KiB block */
-#define	OPCODE_BE_4K_PMC	0xd7	/* Erase 4KiB block on PMC chips */
-#define	OPCODE_BE_32K		0x52	/* Erase 32KiB block */
-#define	OPCODE_CHIP_ERASE	0xc7	/* Erase whole flash chip */
-#define	OPCODE_SE		0xd8	/* Sector erase (usually 64KiB) */
-#define	OPCODE_RDID		0x9f	/* Read JEDEC ID */
-#define	OPCODE_RDCR             0x35    /* Read configuration register */
-
-/* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
-#define	OPCODE_NORM_READ_4B	0x13	/* Read data bytes (low frequency) */
-#define	OPCODE_FAST_READ_4B	0x0c	/* Read data bytes (high frequency) */
-#define	OPCODE_DUAL_READ_4B	0x3c    /* Read data bytes (Dual SPI) */
-#define	OPCODE_QUAD_READ_4B	0x6c    /* Read data bytes (Quad SPI) */
-#define	OPCODE_PP_4B		0x12	/* Page program (up to 256 bytes) */
-#define	OPCODE_SE_4B		0xdc	/* Sector erase (usually 64KiB) */
-
-/* Used for SST flashes only. */
-#define	OPCODE_BP		0x02	/* Byte program */
-#define	OPCODE_WRDI		0x04	/* Write disable */
-#define	OPCODE_AAI_WP		0xad	/* Auto address increment word program */
-
-/* Used for Macronix and Winbond flashes. */
-#define	OPCODE_EN4B		0xb7	/* Enter 4-byte mode */
-#define	OPCODE_EX4B		0xe9	/* Exit 4-byte mode */
-
-/* Used for Spansion flashes only. */
-#define	OPCODE_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 */
-
-/* Configuration Register bits. */
-#define CR_QUAD_EN_SPAN		0x2     /* Spansion Quad I/O */
-
-/* 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	MAX_CMD_SIZE		6
-
-#define JEDEC_MFR(_jedec_id)	((_jedec_id) >> 16)
-
-/****************************************************************************/
-
-enum read_type {
-	M25P80_NORMAL = 0,
-	M25P80_FAST,
-	M25P80_DUAL,
-	M25P80_QUAD,
-};
-
-struct m25p {
-	struct spi_device	*spi;
-	struct mutex		lock;
-	struct mtd_info		mtd;
-	u16			page_size;
-	u16			addr_width;
-	u8			erase_opcode;
-	u8			read_opcode;
-	u8			program_opcode;
-	u8			*command;
-	enum read_type		flash_read;
-};
-
-static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
-{
-	return container_of(mtd, struct m25p, mtd);
-}
-
-/****************************************************************************/
-
-/*
- * Internal helper functions
- */
-
-/*
- * 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 m25p *flash)
-{
-	ssize_t retval;
-	u8 code = OPCODE_RDSR;
-	u8 val;
-
-	retval = spi_write_then_read(flash->spi, &code, 1, &val, 1);
-
-	if (retval < 0) {
-		dev_err(&flash->spi->dev, "error %d reading SR\n",
-				(int) retval);
-		return retval;
-	}
-
-	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 m25p *flash)
-{
-	u8 code = OPCODE_RDCR;
-	int ret;
-	u8 val;
-
-	ret = spi_write_then_read(flash->spi, &code, 1, &val, 1);
-	if (ret < 0) {
-		dev_err(&flash->spi->dev, "error %d reading CR\n", ret);
-		return ret;
-	}
-
-	return val;
-}
-
-/*
- * Write status register 1 byte
- * Returns negative if error occurred.
- */
-static int write_sr(struct m25p *flash, u8 val)
-{
-	flash->command[0] = OPCODE_WRSR;
-	flash->command[1] = val;
-
-	return spi_write(flash->spi, flash->command, 2);
-}
-
-/*
- * Set write enable latch with Write Enable command.
- * Returns negative if error occurred.
- */
-static inline int write_enable(struct m25p *flash)
-{
-	u8	code = OPCODE_WREN;
-
-	return spi_write_then_read(flash->spi, &code, 1, NULL, 0);
-}
-
-/*
- * Send write disble instruction to the chip.
- */
-static inline int write_disable(struct m25p *flash)
-{
-	u8	code = OPCODE_WRDI;
-
-	return spi_write_then_read(flash->spi, &code, 1, NULL, 0);
-}
-
-/*
- * Enable/disable 4-byte addressing mode.
- */
-static inline int set_4byte(struct m25p *flash, u32 jedec_id, int enable)
-{
-	int status;
-	bool need_wren = false;
-
-	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(flash);
-
-		flash->command[0] = enable ? OPCODE_EN4B : OPCODE_EX4B;
-		status = spi_write(flash->spi, flash->command, 1);
-
-		if (need_wren)
-			write_disable(flash);
-
-		return status;
-	default:
-		/* Spansion style */
-		flash->command[0] = OPCODE_BRWR;
-		flash->command[1] = enable << 7;
-		return spi_write(flash->spi, flash->command, 2);
-	}
-}
-
-/*
- * Service routine to read status register until ready, or timeout occurs.
- * Returns non-zero if error.
- */
-static int wait_till_ready(struct m25p *flash)
-{
-	unsigned long deadline;
-	int sr;
-
-	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
-
-	do {
-		if ((sr = read_sr(flash)) < 0)
-			break;
-		else if (!(sr & SR_WIP))
-			return 0;
-
-		cond_resched();
-
-	} while (!time_after_eq(jiffies, deadline));
-
-	return 1;
-}
-
-/*
- * 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 m25p *flash, u16 val)
-{
-	flash->command[0] = OPCODE_WRSR;
-	flash->command[1] = val & 0xff;
-	flash->command[2] = (val >> 8);
-
-	return spi_write(flash->spi, flash->command, 3);
-}
-
-static int macronix_quad_enable(struct m25p *flash)
-{
-	int ret, val;
-	u8 cmd[2];
-	cmd[0] = OPCODE_WRSR;
-
-	val = read_sr(flash);
-	cmd[1] = val | SR_QUAD_EN_MX;
-	write_enable(flash);
-
-	spi_write(flash->spi, &cmd, 2);
-
-	if (wait_till_ready(flash))
-		return 1;
-
-	ret = read_sr(flash);
-	if (!(ret > 0 && (ret & SR_QUAD_EN_MX))) {
-		dev_err(&flash->spi->dev, "Macronix Quad bit not set\n");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int spansion_quad_enable(struct m25p *flash)
-{
-	int ret;
-	int quad_en = CR_QUAD_EN_SPAN << 8;
-
-	write_enable(flash);
-
-	ret = write_sr_cr(flash, quad_en);
-	if (ret < 0) {
-		dev_err(&flash->spi->dev,
-			"error while writing configuration register\n");
-		return -EINVAL;
-	}
-
-	/* read back and check it */
-	ret = read_cr(flash);
-	if (!(ret > 0 && (ret & CR_QUAD_EN_SPAN))) {
-		dev_err(&flash->spi->dev, "Spansion Quad bit not set\n");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int set_quad_mode(struct m25p *flash, u32 jedec_id)
-{
-	int status;
-
-	switch (JEDEC_MFR(jedec_id)) {
-	case CFI_MFR_MACRONIX:
-		status = macronix_quad_enable(flash);
-		if (status) {
-			dev_err(&flash->spi->dev,
-				"Macronix quad-read not enabled\n");
-			return -EINVAL;
-		}
-		return status;
-	default:
-		status = spansion_quad_enable(flash);
-		if (status) {
-			dev_err(&flash->spi->dev,
-				"Spansion quad-read not enabled\n");
-			return -EINVAL;
-		}
-		return status;
-	}
-}
-
-/*
- * Erase the whole flash memory
- *
- * Returns 0 if successful, non-zero otherwise.
- */
-static int erase_chip(struct m25p *flash)
-{
-	pr_debug("%s: %s %lldKiB\n", dev_name(&flash->spi->dev), __func__,
-			(long long)(flash->mtd.size >> 10));
-
-	/* Wait until finished previous write command. */
-	if (wait_till_ready(flash))
-		return 1;
-
-	/* Send write enable, then erase commands. */
-	write_enable(flash);
-
-	/* Set up command buffer. */
-	flash->command[0] = OPCODE_CHIP_ERASE;
-
-	spi_write(flash->spi, flash->command, 1);
-
-	return 0;
-}
-
-static void m25p_addr2cmd(struct m25p *flash, unsigned int addr, u8 *cmd)
-{
-	/* opcode is in cmd[0] */
-	cmd[1] = addr >> (flash->addr_width * 8 -  8);
-	cmd[2] = addr >> (flash->addr_width * 8 - 16);
-	cmd[3] = addr >> (flash->addr_width * 8 - 24);
-	cmd[4] = addr >> (flash->addr_width * 8 - 32);
-}
-
-static int m25p_cmdsz(struct m25p *flash)
-{
-	return 1 + flash->addr_width;
-}
-
-/*
- * Erase one sector of flash memory at offset ``offset'' which is any
- * address within the sector which should be erased.
- *
- * Returns 0 if successful, non-zero otherwise.
- */
-static int erase_sector(struct m25p *flash, u32 offset)
-{
-	pr_debug("%s: %s %dKiB at 0x%08x\n", dev_name(&flash->spi->dev),
-			__func__, flash->mtd.erasesize / 1024, offset);
-
-	/* Wait until finished previous write command. */
-	if (wait_till_ready(flash))
-		return 1;
-
-	/* Send write enable, then erase commands. */
-	write_enable(flash);
-
-	/* Set up command buffer. */
-	flash->command[0] = flash->erase_opcode;
-	m25p_addr2cmd(flash, offset, flash->command);
-
-	spi_write(flash->spi, flash->command, m25p_cmdsz(flash));
-
-	return 0;
-}
-
-/****************************************************************************/
-
-/*
- * MTD implementation
- */
-
-/*
- * Erase an address range on the flash chip.  The address range may extend
- * one or more erase sectors.  Return an error is there is a problem erasing.
- */
-static int m25p80_erase(struct mtd_info *mtd, struct erase_info *instr)
-{
-	struct m25p *flash = mtd_to_m25p(mtd);
-	u32 addr,len;
-	uint32_t rem;
-
-	pr_debug("%s: %s at 0x%llx, len %lld\n", dev_name(&flash->spi->dev),
-			__func__, (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;
-
-	mutex_lock(&flash->lock);
-
-	/* whole-chip erase? */
-	if (len == flash->mtd.size) {
-		if (erase_chip(flash)) {
-			instr->state = MTD_ERASE_FAILED;
-			mutex_unlock(&flash->lock);
-			return -EIO;
-		}
-
-	/* REVISIT in some cases we could speed up erasing large regions
-	 * by using OPCODE_SE instead of OPCODE_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 (erase_sector(flash, addr)) {
-				instr->state = MTD_ERASE_FAILED;
-				mutex_unlock(&flash->lock);
-				return -EIO;
-			}
-
-			addr += mtd->erasesize;
-			len -= mtd->erasesize;
-		}
-	}
-
-	mutex_unlock(&flash->lock);
-
-	instr->state = MTD_ERASE_DONE;
-	mtd_erase_callback(instr);
-
-	return 0;
-}
-
-/*
- * Dummy Cycle calculation for different type of read.
- * It can be used to support more commands with
- * different dummy cycle requirements.
- */
-static inline int m25p80_dummy_cycles_read(struct m25p *flash)
-{
-	switch (flash->flash_read) {
-	case M25P80_FAST:
-	case M25P80_DUAL:
-	case M25P80_QUAD:
-		return 1;
-	case M25P80_NORMAL:
-		return 0;
-	default:
-		dev_err(&flash->spi->dev, "No valid read type supported\n");
-		return -1;
-	}
-}
-
-static inline unsigned int m25p80_rx_nbits(const struct m25p *flash)
-{
-	switch (flash->flash_read) {
-	case M25P80_DUAL:
-		return 2;
-	case M25P80_QUAD:
-		return 4;
-	default:
-		return 0;
-	}
-}
-
-/*
- * Read an address range from the flash chip.  The address range
- * may be any size provided it is within the physical boundaries.
- */
-static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len,
-	size_t *retlen, u_char *buf)
-{
-	struct m25p *flash = mtd_to_m25p(mtd);
-	struct spi_transfer t[2];
-	struct spi_message m;
-	uint8_t opcode;
-	int dummy;
-
-	pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
-			__func__, (u32)from, len);
-
-	spi_message_init(&m);
-	memset(t, 0, (sizeof t));
-
-	dummy =  m25p80_dummy_cycles_read(flash);
-	if (dummy < 0) {
-		dev_err(&flash->spi->dev, "No valid read command supported\n");
-		return -EINVAL;
-	}
-
-	t[0].tx_buf = flash->command;
-	t[0].len = m25p_cmdsz(flash) + dummy;
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].rx_buf = buf;
-	t[1].rx_nbits = m25p80_rx_nbits(flash);
-	t[1].len = len;
-	spi_message_add_tail(&t[1], &m);
-
-	mutex_lock(&flash->lock);
-
-	/* Wait till previous write/erase is done. */
-	if (wait_till_ready(flash)) {
-		/* REVISIT status return?? */
-		mutex_unlock(&flash->lock);
-		return 1;
-	}
-
-	/* Set up the write data buffer. */
-	opcode = flash->read_opcode;
-	flash->command[0] = opcode;
-	m25p_addr2cmd(flash, from, flash->command);
-
-	spi_sync(flash->spi, &m);
-
-	*retlen = m.actual_length - m25p_cmdsz(flash) - dummy;
-
-	mutex_unlock(&flash->lock);
-
-	return 0;
-}
-
-/*
- * Write an address range to the flash 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 m25p80_write(struct mtd_info *mtd, loff_t to, size_t len,
-	size_t *retlen, const u_char *buf)
-{
-	struct m25p *flash = mtd_to_m25p(mtd);
-	u32 page_offset, page_size;
-	struct spi_transfer t[2];
-	struct spi_message m;
-
-	pr_debug("%s: %s to 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
-			__func__, (u32)to, len);
-
-	spi_message_init(&m);
-	memset(t, 0, (sizeof t));
-
-	t[0].tx_buf = flash->command;
-	t[0].len = m25p_cmdsz(flash);
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].tx_buf = buf;
-	spi_message_add_tail(&t[1], &m);
-
-	mutex_lock(&flash->lock);
-
-	/* Wait until finished previous write command. */
-	if (wait_till_ready(flash)) {
-		mutex_unlock(&flash->lock);
-		return 1;
-	}
-
-	write_enable(flash);
-
-	/* Set up the opcode in the write buffer. */
-	flash->command[0] = flash->program_opcode;
-	m25p_addr2cmd(flash, to, flash->command);
-
-	page_offset = to & (flash->page_size - 1);
-
-	/* do all the bytes fit onto one page? */
-	if (page_offset + len <= flash->page_size) {
-		t[1].len = len;
-
-		spi_sync(flash->spi, &m);
-
-		*retlen = m.actual_length - m25p_cmdsz(flash);
-	} else {
-		u32 i;
-
-		/* the size of data remaining on the first page */
-		page_size = flash->page_size - page_offset;
-
-		t[1].len = page_size;
-		spi_sync(flash->spi, &m);
-
-		*retlen = m.actual_length - m25p_cmdsz(flash);
-
-		/* write everything in flash->page_size chunks */
-		for (i = page_size; i < len; i += page_size) {
-			page_size = len - i;
-			if (page_size > flash->page_size)
-				page_size = flash->page_size;
-
-			/* write the next page to flash */
-			m25p_addr2cmd(flash, to + i, flash->command);
-
-			t[1].tx_buf = buf + i;
-			t[1].len = page_size;
-
-			wait_till_ready(flash);
-
-			write_enable(flash);
-
-			spi_sync(flash->spi, &m);
-
-			*retlen += m.actual_length - m25p_cmdsz(flash);
-		}
-	}
-
-	mutex_unlock(&flash->lock);
-
-	return 0;
-}
-
-static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
-		size_t *retlen, const u_char *buf)
-{
-	struct m25p *flash = mtd_to_m25p(mtd);
-	struct spi_transfer t[2];
-	struct spi_message m;
-	size_t actual;
-	int cmd_sz, ret;
-
-	pr_debug("%s: %s to 0x%08x, len %zd\n", dev_name(&flash->spi->dev),
-			__func__, (u32)to, len);
-
-	spi_message_init(&m);
-	memset(t, 0, (sizeof t));
-
-	t[0].tx_buf = flash->command;
-	t[0].len = m25p_cmdsz(flash);
-	spi_message_add_tail(&t[0], &m);
-
-	t[1].tx_buf = buf;
-	spi_message_add_tail(&t[1], &m);
-
-	mutex_lock(&flash->lock);
-
-	/* Wait until finished previous write command. */
-	ret = wait_till_ready(flash);
-	if (ret)
-		goto time_out;
-
-	write_enable(flash);
-
-	actual = to % 2;
-	/* Start write from odd address. */
-	if (actual) {
-		flash->command[0] = OPCODE_BP;
-		m25p_addr2cmd(flash, to, flash->command);
-
-		/* write one byte. */
-		t[1].len = 1;
-		spi_sync(flash->spi, &m);
-		ret = wait_till_ready(flash);
-		if (ret)
-			goto time_out;
-		*retlen += m.actual_length - m25p_cmdsz(flash);
-	}
-	to += actual;
-
-	flash->command[0] = OPCODE_AAI_WP;
-	m25p_addr2cmd(flash, to, flash->command);
-
-	/* Write out most of the data here. */
-	cmd_sz = m25p_cmdsz(flash);
-	for (; actual < len - 1; actual += 2) {
-		t[0].len = cmd_sz;
-		/* write two bytes. */
-		t[1].len = 2;
-		t[1].tx_buf = buf + actual;
-
-		spi_sync(flash->spi, &m);
-		ret = wait_till_ready(flash);
-		if (ret)
-			goto time_out;
-		*retlen += m.actual_length - cmd_sz;
-		cmd_sz = 1;
-		to += 2;
-	}
-	write_disable(flash);
-	ret = wait_till_ready(flash);
-	if (ret)
-		goto time_out;
-
-	/* Write out trailing byte if it exists. */
-	if (actual != len) {
-		write_enable(flash);
-		flash->command[0] = OPCODE_BP;
-		m25p_addr2cmd(flash, to, flash->command);
-		t[0].len = m25p_cmdsz(flash);
-		t[1].len = 1;
-		t[1].tx_buf = buf + actual;
-
-		spi_sync(flash->spi, &m);
-		ret = wait_till_ready(flash);
-		if (ret)
-			goto time_out;
-		*retlen += m.actual_length - m25p_cmdsz(flash);
-		write_disable(flash);
-	}
-
-time_out:
-	mutex_unlock(&flash->lock);
-	return ret;
-}
-
-static int m25p80_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
-{
-	struct m25p *flash = mtd_to_m25p(mtd);
-	uint32_t offset = ofs;
-	uint8_t status_old, status_new;
-	int res = 0;
-
-	mutex_lock(&flash->lock);
-	/* Wait until finished previous command */
-	if (wait_till_ready(flash)) {
-		res = 1;
-		goto err;
-	}
-
-	status_old = read_sr(flash);
-
-	if (offset < flash->mtd.size-(flash->mtd.size/2))
-		status_new = status_old | SR_BP2 | SR_BP1 | SR_BP0;
-	else if (offset < flash->mtd.size-(flash->mtd.size/4))
-		status_new = (status_old & ~SR_BP0) | SR_BP2 | SR_BP1;
-	else if (offset < flash->mtd.size-(flash->mtd.size/8))
-		status_new = (status_old & ~SR_BP1) | SR_BP2 | SR_BP0;
-	else if (offset < flash->mtd.size-(flash->mtd.size/16))
-		status_new = (status_old & ~(SR_BP0|SR_BP1)) | SR_BP2;
-	else if (offset < flash->mtd.size-(flash->mtd.size/32))
-		status_new = (status_old & ~SR_BP2) | SR_BP1 | SR_BP0;
-	else if (offset < flash->mtd.size-(flash->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(flash);
-		if (write_sr(flash, status_new) < 0) {
-			res = 1;
-			goto err;
-		}
-	}
-
-err:	mutex_unlock(&flash->lock);
-	return res;
-}
-
-static int m25p80_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
-{
-	struct m25p *flash = mtd_to_m25p(mtd);
-	uint32_t offset = ofs;
-	uint8_t status_old, status_new;
-	int res = 0;
-
-	mutex_lock(&flash->lock);
-	/* Wait until finished previous command */
-	if (wait_till_ready(flash)) {
-		res = 1;
-		goto err;
-	}
-
-	status_old = read_sr(flash);
-
-	if (offset+len > flash->mtd.size-(flash->mtd.size/64))
-		status_new = status_old & ~(SR_BP2|SR_BP1|SR_BP0);
-	else if (offset+len > flash->mtd.size-(flash->mtd.size/32))
-		status_new = (status_old & ~(SR_BP2|SR_BP1)) | SR_BP0;
-	else if (offset+len > flash->mtd.size-(flash->mtd.size/16))
-		status_new = (status_old & ~(SR_BP2|SR_BP0)) | SR_BP1;
-	else if (offset+len > flash->mtd.size-(flash->mtd.size/8))
-		status_new = (status_old & ~SR_BP2) | SR_BP1 | SR_BP0;
-	else if (offset+len > flash->mtd.size-(flash->mtd.size/4))
-		status_new = (status_old & ~(SR_BP0|SR_BP1)) | SR_BP2;
-	else if (offset+len > flash->mtd.size-(flash->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(flash);
-		if (write_sr(flash, status_new) < 0) {
-			res = 1;
-			goto err;
-		}
-	}
-
-err:	mutex_unlock(&flash->lock);
-	return res;
-}
-
-/****************************************************************************/
-
-/*
- * SPI device driver setup and teardown
- */
-
-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 OPCODE_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		/* OPCODE_BE_4K works uniformly */
-#define	M25P_NO_ERASE	0x02		/* No erase command needed */
-#define	SST_WRITE	0x04		/* use SST byte programming */
-#define	M25P_NO_FR	0x08		/* Can't do fastread */
-#define	SECT_4K_PMC	0x10		/* OPCODE_BE_4K_PMC works uniformly */
-#define	M25P80_DUAL_READ	0x20    /* Flash supports Dual Read */
-#define	M25P80_QUAD_READ	0x40    /* Flash supports Quad Read */
-};
-
-#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 flash chips.  This current list focusses on newer chips, which
- * have been converging on command sets which including JEDEC ID.
- */
-static const struct spi_device_id m25p_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) },
-	{ "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, M25P_NO_ERASE | M25P_NO_FR) },
-	{ "mr25h10",  CAT25_INFO(128 * 1024, 1, 256, 3, M25P_NO_ERASE | M25P_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, M25P80_QUAD_READ) },
-	{ "mx66l1g55g",  INFO(0xc2261b, 0, 64 * 1024, 2048, M25P80_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) },
-
-	/* 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, 0) },
-	{ "s25sl064p",  INFO(0x010216, 0x4d00,  64 * 1024, 128, 0) },
-	{ "s25fl256s0", INFO(0x010219, 0x4d00, 256 * 1024, 128, 0) },
-	{ "s25fl256s1", INFO(0x010219, 0x4d01,  64 * 1024, 512, M25P80_DUAL_READ | M25P80_QUAD_READ) },
-	{ "s25fl512s",  INFO(0x010220, 0x4d00, 256 * 1024, 256, M25P80_DUAL_READ | M25P80_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, M25P_NO_ERASE | M25P_NO_FR) },
-	{ "cat25c03", CAT25_INFO(  32, 8, 16, 2, M25P_NO_ERASE | M25P_NO_FR) },
-	{ "cat25c09", CAT25_INFO( 128, 8, 32, 2, M25P_NO_ERASE | M25P_NO_FR) },
-	{ "cat25c17", CAT25_INFO( 256, 8, 32, 2, M25P_NO_ERASE | M25P_NO_FR) },
-	{ "cat25128", CAT25_INFO(2048, 8, 64, 2, M25P_NO_ERASE | M25P_NO_FR) },
-	{ },
-};
-MODULE_DEVICE_TABLE(spi, m25p_ids);
-
-static const struct spi_device_id *jedec_probe(struct spi_device *spi)
-{
-	int			tmp;
-	u8			code = OPCODE_RDID;
-	u8			id[5];
-	u32			jedec;
-	u16                     ext_jedec;
-	struct flash_info	*info;
-
-	/* JEDEC also defines an optional "extended device information"
-	 * string for after vendor-specific data, after the three bytes
-	 * we use here.  Supporting some chips might require using it.
-	 */
-	tmp = spi_write_then_read(spi, &code, 1, id, 5);
-	if (tmp < 0) {
-		pr_debug("%s: error %d reading JEDEC ID\n",
-				dev_name(&spi->dev), 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(m25p_ids) - 1; tmp++) {
-		info = (void *)m25p_ids[tmp].driver_data;
-		if (info->jedec_id == jedec) {
-			if (info->ext_id == 0 || info->ext_id == ext_jedec)
-				return &m25p_ids[tmp];
-		}
-	}
-	dev_err(&spi->dev, "unrecognized JEDEC id %06x\n", jedec);
-	return ERR_PTR(-ENODEV);
-}
-
-
-/*
- * board specific setup should have ensured the SPI clock used here
- * matches what the READ command supports, at least until this driver
- * understands FAST_READ (for clocks over 25 MHz).
- */
-static int m25p_probe(struct spi_device *spi)
-{
-	const struct spi_device_id	*id = spi_get_device_id(spi);
-	struct flash_platform_data	*data;
-	struct m25p			*flash;
-	struct flash_info		*info;
-	unsigned			i;
-	struct mtd_part_parser_data	ppdata;
-	struct device_node *np = spi->dev.of_node;
-	int 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(&spi->dev);
-	if (data && data->type) {
-		const struct spi_device_id *plat_id;
-
-		for (i = 0; i < ARRAY_SIZE(m25p_ids) - 1; i++) {
-			plat_id = &m25p_ids[i];
-			if (strcmp(data->type, plat_id->name))
-				continue;
-			break;
-		}
-
-		if (i < ARRAY_SIZE(m25p_ids) - 1)
-			id = plat_id;
-		else
-			dev_warn(&spi->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(spi);
-		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(&spi->dev, "found %s, expected %s\n",
-				 jid->name, id->name);
-			id = jid;
-			info = (void *)jid->driver_data;
-		}
-	}
-
-	flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL);
-	if (!flash)
-		return -ENOMEM;
-
-	flash->command = devm_kzalloc(&spi->dev, MAX_CMD_SIZE, GFP_KERNEL);
-	if (!flash->command)
-		return -ENOMEM;
-
-	flash->spi = spi;
-	mutex_init(&flash->lock);
-	spi_set_drvdata(spi, flash);
-
-	/*
-	 * Atmel, SST and Intel/Numonyx serial flash 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(flash);
-		write_sr(flash, 0);
-	}
-
-	if (data && data->name)
-		flash->mtd.name = data->name;
-	else
-		flash->mtd.name = dev_name(&spi->dev);
-
-	flash->mtd.type = MTD_NORFLASH;
-	flash->mtd.writesize = 1;
-	flash->mtd.flags = MTD_CAP_NORFLASH;
-	flash->mtd.size = info->sector_size * info->n_sectors;
-	flash->mtd._erase = m25p80_erase;
-	flash->mtd._read = m25p80_read;
-
-	/* flash protection support for STmicro chips */
-	if (JEDEC_MFR(info->jedec_id) == CFI_MFR_ST) {
-		flash->mtd._lock = m25p80_lock;
-		flash->mtd._unlock = m25p80_unlock;
-	}
-
-	/* sst flash chips use AAI word program */
-	if (info->flags & SST_WRITE)
-		flash->mtd._write = sst_write;
-	else
-		flash->mtd._write = m25p80_write;
-
-	/* prefer "small sector" erase if possible */
-	if (info->flags & SECT_4K) {
-		flash->erase_opcode = OPCODE_BE_4K;
-		flash->mtd.erasesize = 4096;
-	} else if (info->flags & SECT_4K_PMC) {
-		flash->erase_opcode = OPCODE_BE_4K_PMC;
-		flash->mtd.erasesize = 4096;
-	} else {
-		flash->erase_opcode = OPCODE_SE;
-		flash->mtd.erasesize = info->sector_size;
-	}
-
-	if (info->flags & M25P_NO_ERASE)
-		flash->mtd.flags |= MTD_NO_ERASE;
-
-	ppdata.of_node = spi->dev.of_node;
-	flash->mtd.dev.parent = &spi->dev;
-	flash->page_size = info->page_size;
-	flash->mtd.writebufsize = flash->page_size;
-
-	if (np) {
-		/* If we were instantiated by DT, use it */
-		if (of_property_read_bool(np, "m25p,fast-read"))
-			flash->flash_read = M25P80_FAST;
-		else
-			flash->flash_read = M25P80_NORMAL;
-	} else {
-		/* If we weren't instantiated by DT, default to fast-read */
-		flash->flash_read = M25P80_FAST;
-	}
-
-	/* Some devices cannot do fast-read, no matter what DT tells us */
-	if (info->flags & M25P_NO_FR)
-		flash->flash_read = M25P80_NORMAL;
-
-	/* Quad/Dual-read mode takes precedence over fast/normal */
-	if (spi->mode & SPI_RX_QUAD && info->flags & M25P80_QUAD_READ) {
-		ret = set_quad_mode(flash, info->jedec_id);
-		if (ret) {
-			dev_err(&flash->spi->dev, "quad mode not supported\n");
-			return ret;
-		}
-		flash->flash_read = M25P80_QUAD;
-	} else if (spi->mode & SPI_RX_DUAL && info->flags & M25P80_DUAL_READ) {
-		flash->flash_read = M25P80_DUAL;
-	}
-
-	/* Default commands */
-	switch (flash->flash_read) {
-	case M25P80_QUAD:
-		flash->read_opcode = OPCODE_QUAD_READ;
-		break;
-	case M25P80_DUAL:
-		flash->read_opcode = OPCODE_DUAL_READ;
-		break;
-	case M25P80_FAST:
-		flash->read_opcode = OPCODE_FAST_READ;
-		break;
-	case M25P80_NORMAL:
-		flash->read_opcode = OPCODE_NORM_READ;
-		break;
-	default:
-		dev_err(&flash->spi->dev, "No Read opcode defined\n");
-		return -EINVAL;
-	}
-
-	flash->program_opcode = OPCODE_PP;
-
-	if (info->addr_width)
-		flash->addr_width = info->addr_width;
-	else if (flash->mtd.size > 0x1000000) {
-		/* enable 4-byte addressing if the device exceeds 16MiB */
-		flash->addr_width = 4;
-		if (JEDEC_MFR(info->jedec_id) == CFI_MFR_AMD) {
-			/* Dedicated 4-byte command set */
-			switch (flash->flash_read) {
-			case M25P80_QUAD:
-				flash->read_opcode = OPCODE_QUAD_READ_4B;
-				break;
-			case M25P80_DUAL:
-				flash->read_opcode = OPCODE_DUAL_READ_4B;
-				break;
-			case M25P80_FAST:
-				flash->read_opcode = OPCODE_FAST_READ_4B;
-				break;
-			case M25P80_NORMAL:
-				flash->read_opcode = OPCODE_NORM_READ_4B;
-				break;
-			}
-			flash->program_opcode = OPCODE_PP_4B;
-			/* No small sector erase for 4-byte command set */
-			flash->erase_opcode = OPCODE_SE_4B;
-			flash->mtd.erasesize = info->sector_size;
-		} else
-			set_4byte(flash, info->jedec_id, 1);
-	} else {
-		flash->addr_width = 3;
-	}
-
-	dev_info(&spi->dev, "%s (%lld Kbytes)\n", id->name,
-			(long long)flash->mtd.size >> 10);
-
-	pr_debug("mtd .name = %s, .size = 0x%llx (%lldMiB) "
-			".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
-		flash->mtd.name,
-		(long long)flash->mtd.size, (long long)(flash->mtd.size >> 20),
-		flash->mtd.erasesize, flash->mtd.erasesize / 1024,
-		flash->mtd.numeraseregions);
-
-	if (flash->mtd.numeraseregions)
-		for (i = 0; i < flash->mtd.numeraseregions; i++)
-			pr_debug("mtd.eraseregions[%d] = { .offset = 0x%llx, "
-				".erasesize = 0x%.8x (%uKiB), "
-				".numblocks = %d }\n",
-				i, (long long)flash->mtd.eraseregions[i].offset,
-				flash->mtd.eraseregions[i].erasesize,
-				flash->mtd.eraseregions[i].erasesize / 1024,
-				flash->mtd.eraseregions[i].numblocks);
-
-
-	/* partitions should match sector boundaries; and it may be good to
-	 * use readonly partitions for writeprotected sectors (BP2..BP0).
-	 */
-	return mtd_device_parse_register(&flash->mtd, NULL, &ppdata,
-			data ? data->parts : NULL,
-			data ? data->nr_parts : 0);
-}
-
-
-static int m25p_remove(struct spi_device *spi)
-{
-	struct m25p	*flash = spi_get_drvdata(spi);
-
-	/* Clean up MTD stuff. */
-	return mtd_device_unregister(&flash->mtd);
-}
-
-
-static struct spi_driver m25p80_driver = {
-	.driver = {
-		.name	= "m25p80",
-		.owner	= THIS_MODULE,
-	},
-	.id_table	= m25p_ids,
-	.probe	= m25p_probe,
-	.remove	= m25p_remove,
-
-	/* REVISIT: many of these chips have deep power-down modes, which
-	 * should clearly be entered on suspend() to minimize power use.
-	 * And also when they're otherwise idle...
-	 */
-};
-
-module_spi_driver(m25p80_driver);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Mike Lavender");
-MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");
+/*
+ * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
+ *
+ * Author: Mike Lavender, mike at steroidmicros.com
+ *
+ * Copyright (c) 2005, Intec Automation Inc.
+ *
+ * Some parts are based on lart.c by Abraham Van Der Merwe
+ *
+ * Cleaned up and generalized based on mtd_dataflash.c
+ *
+ * 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/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+#include <linux/spi/spi.h>
+#include <linux/spi/flash.h>
+#include <linux/mtd/spi-nor.h>
+
+#define	MAX_CMD_SIZE		6
+struct m25p {
+	struct spi_device	*spi;
+	struct spi_nor		spi_nor;
+	struct mtd_info		mtd;
+	u8			command[MAX_CMD_SIZE];
+};
+
+static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len)
+{
+	struct m25p *flash = nor->priv;
+	struct spi_device *spi = flash->spi;
+	int ret;
+
+	ret = spi_write_then_read(spi, &code, 1, val, len);
+	if (ret < 0)
+		dev_err(&spi->dev, "error %d reading %x\n", ret, code);
+
+	return ret;
+}
+
+static void m25p_addr2cmd(struct spi_nor *nor, unsigned int addr, u8 *cmd)
+{
+	/* opcode is in cmd[0] */
+	cmd[1] = addr >> (nor->addr_width * 8 -  8);
+	cmd[2] = addr >> (nor->addr_width * 8 - 16);
+	cmd[3] = addr >> (nor->addr_width * 8 - 24);
+	cmd[4] = addr >> (nor->addr_width * 8 - 32);
+}
+
+static int m25p_cmdsz(struct spi_nor *nor)
+{
+	return 1 + nor->addr_width;
+}
+
+static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len,
+			int wr_en)
+{
+	struct m25p *flash = nor->priv;
+	struct spi_device *spi = flash->spi;
+
+	flash->command[0] = opcode;
+	if (buf)
+		memcpy(&flash->command[1], buf, len);
+
+	return spi_write(spi, flash->command, len + 1);
+}
+
+static void m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
+			size_t *retlen, const u_char *buf)
+{
+	struct m25p *flash = nor->priv;
+	struct spi_device *spi = flash->spi;
+	struct spi_transfer t[2] = {};
+	struct spi_message m;
+	int cmd_sz = m25p_cmdsz(nor);
+
+	spi_message_init(&m);
+
+	if (nor->program_opcode == OPCODE_AAI_WP && nor->sst_write_second)
+		cmd_sz = 1;
+
+	flash->command[0] = nor->program_opcode;
+	m25p_addr2cmd(nor, to, flash->command);
+
+	t[0].tx_buf = flash->command;
+	t[0].len = cmd_sz;
+	spi_message_add_tail(&t[0], &m);
+
+	t[1].tx_buf = buf;
+	t[1].len = len;
+	spi_message_add_tail(&t[1], &m);
+
+	spi_sync(spi, &m);
+
+	*retlen += m.actual_length - cmd_sz;
+}
+
+static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor)
+{
+	switch (nor->flash_read) {
+	case SPI_NOR_DUAL:
+		return 2;
+	case SPI_NOR_QUAD:
+		return 4;
+	default:
+		return 0;
+	}
+}
+
+/*
+ * Read an address range from the nor chip.  The address range
+ * may be any size provided it is within the physical boundaries.
+ */
+static int m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
+			size_t *retlen, u_char *buf)
+{
+	struct m25p *flash = nor->priv;
+	struct spi_device *spi = flash->spi;
+	struct spi_transfer t[2];
+	struct spi_message m;
+	int dummy = nor->read_dummy;
+	int ret;
+
+	/* Wait till previous write/erase is done. */
+	ret = nor->wait_till_ready(nor);
+	if (ret)
+		return ret;
+
+	spi_message_init(&m);
+	memset(t, 0, (sizeof t));
+
+	flash->command[0] = nor->read_opcode;
+	m25p_addr2cmd(nor, from, flash->command);
+
+	t[0].tx_buf = flash->command;
+	t[0].len = m25p_cmdsz(nor) + dummy;
+	spi_message_add_tail(&t[0], &m);
+
+	t[1].rx_buf = buf;
+	t[1].rx_nbits = m25p80_rx_nbits(nor);
+	t[1].len = len;
+	spi_message_add_tail(&t[1], &m);
+
+	spi_sync(spi, &m);
+
+	*retlen = m.actual_length - m25p_cmdsz(nor) - dummy;
+	return 0;
+}
+
+static int m25p80_erase(struct spi_nor *nor, loff_t offset)
+{
+	struct m25p *flash = nor->priv;
+	int ret;
+
+	dev_dbg(nor->dev, "%dKiB at 0x%08x\n",
+		flash->mtd.erasesize / 1024, (u32)offset);
+
+	/* 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, OPCODE_WREN, NULL, 0, 0);
+	if (ret)
+		return ret;
+
+	/* Set up command buffer. */
+	flash->command[0] = nor->erase_opcode;
+	m25p_addr2cmd(nor, offset, flash->command);
+
+	spi_write(flash->spi, flash->command, m25p_cmdsz(nor));
+
+	return 0;
+}
+
+/*
+ * board specific setup should have ensured the SPI clock used here
+ * matches what the READ command supports, at least until this driver
+ * understands FAST_READ (for clocks over 25 MHz).
+ */
+static int m25p_probe(struct spi_device *spi)
+{
+	struct mtd_part_parser_data	ppdata;
+	struct flash_platform_data	*data;
+	struct m25p *flash;
+	struct spi_nor *nor;
+	enum read_mode mode = SPI_NOR_NORMAL;
+	int ret;
+
+	flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL);
+	if (!flash)
+		return -ENOMEM;
+
+	nor = &flash->spi_nor;
+
+	/* install the hooks */
+	nor->read = m25p80_read;
+	nor->write = m25p80_write;
+	nor->erase = m25p80_erase;
+	nor->write_reg = m25p80_write_reg;
+	nor->read_reg = m25p80_read_reg;
+
+	nor->dev = &spi->dev;
+	nor->mtd = &flash->mtd;
+	nor->priv = flash;
+
+	spi_set_drvdata(spi, flash);
+	flash->mtd.priv = nor;
+	flash->spi = spi;
+
+	if (spi->mode & SPI_RX_QUAD)
+		mode = SPI_NOR_QUAD;
+	ret = spi_nor_scan(nor, spi_get_device_id(spi), mode);
+	if (ret)
+		return ret;
+
+	data = dev_get_platdata(&spi->dev);
+	ppdata.of_node = spi->dev.of_node;
+
+	return mtd_device_parse_register(&flash->mtd, NULL, &ppdata,
+			data ? data->parts : NULL,
+			data ? data->nr_parts : 0);
+}
+
+
+static int m25p_remove(struct spi_device *spi)
+{
+	struct m25p	*flash = spi_get_drvdata(spi);
+
+	/* Clean up MTD stuff. */
+	return mtd_device_unregister(&flash->mtd);
+}
+
+
+static struct spi_driver m25p80_driver = {
+	.driver = {
+		.name	= "m25p80",
+		.owner	= THIS_MODULE,
+	},
+	.id_table	= spi_nor_ids,
+	.probe	= m25p_probe,
+	.remove	= m25p_remove,
+
+	/* REVISIT: many of these chips have deep power-down modes, which
+	 * should clearly be entered on suspend() to minimize power use.
+	 * And also when they're otherwise idle...
+	 */
+};
+
+module_spi_driver(m25p80_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mike Lavender");
+MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");



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