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linux/drivers/mtd/devices/m25p80.c
Anton Vorontsov 837479d25e mtd: m25p80: Add support for CAT25xxx serial EEPROMs 
CAT25 chips (as manufactured by On Semiconductor, previously Catalyst
Semiconductor) are similar to the original M25Px0 chips, except:

- Address width can vary (1-2 bytes, in contrast to 3 bytes in M25P
  chips). So, implement convenient m25p_addr2cmd() and m25p_cmdsz()
  calls, and place address width information into flash_info struct;

- Page size can vary, therefore we shouldn't hardcode it, so get rid
  of FLASH_PAGESIZE definition, and place the page size information
  into flash_info struct;

- CAT25 EEPROMs don't need to be erased, so add NO_ERASE flag, and
  propagate it to the mtd subsystem.

[dwmw2: Fix up for conflicts with DMA safety patch]
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-11-30 11:29:00 +00:00

987 lines
25 KiB
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/*
* MTD SPI driver for ST M25Pxx (and similar) serial flash chips
*
* Author: Mike Lavender, mike@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/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/math64.h>
#include <linux/mod_devicetable.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.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_PP 0x02 /* Page program (up to 256 bytes) */
#define OPCODE_BE_4K 0x20 /* Erase 4KiB block */
#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 */
/* 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 */
/* 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 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 4
#ifdef CONFIG_M25PXX_USE_FAST_READ
#define OPCODE_READ OPCODE_FAST_READ
#define FAST_READ_DUMMY_BYTE 1
#else
#define OPCODE_READ OPCODE_NORM_READ
#define FAST_READ_DUMMY_BYTE 0
#endif
/****************************************************************************/
struct m25p {
struct spi_device *spi;
struct mutex lock;
struct mtd_info mtd;
unsigned partitioned:1;
u16 page_size;
u16 addr_width;
u8 erase_opcode;
u8 *command;
};
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;
}
/*
* 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);
}
/*
* 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;
}
/*
* Erase the whole flash memory
*
* Returns 0 if successful, non-zero otherwise.
*/
static int erase_chip(struct m25p *flash)
{
DEBUG(MTD_DEBUG_LEVEL3, "%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);
}
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)
{
DEBUG(MTD_DEBUG_LEVEL3, "%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;
DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%llx, len %lld\n",
dev_name(&flash->spi->dev), __func__, "at",
(long long)instr->addr, (long long)instr->len);
/* sanity checks */
if (instr->addr + instr->len > flash->mtd.size)
return -EINVAL;
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;
}
/*
* 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;
DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%08x, len %zd\n",
dev_name(&flash->spi->dev), __func__, "from",
(u32)from, len);
/* sanity checks */
if (!len)
return 0;
if (from + len > flash->mtd.size)
return -EINVAL;
spi_message_init(&m);
memset(t, 0, (sizeof t));
/* NOTE:
* OPCODE_FAST_READ (if available) is faster.
* Should add 1 byte DUMMY_BYTE.
*/
t[0].tx_buf = flash->command;
t[0].len = m25p_cmdsz(flash) + FAST_READ_DUMMY_BYTE;
spi_message_add_tail(&t[0], &m);
t[1].rx_buf = buf;
t[1].len = len;
spi_message_add_tail(&t[1], &m);
/* Byte count starts at zero. */
if (retlen)
*retlen = 0;
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;
}
/* FIXME switch to OPCODE_FAST_READ. It's required for higher
* clocks; and at this writing, every chip this driver handles
* supports that opcode.
*/
/* Set up the write data buffer. */
flash->command[0] = OPCODE_READ;
m25p_addr2cmd(flash, from, flash->command);
spi_sync(flash->spi, &m);
*retlen = m.actual_length - m25p_cmdsz(flash) - FAST_READ_DUMMY_BYTE;
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;
DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%08x, len %zd\n",
dev_name(&flash->spi->dev), __func__, "to",
(u32)to, len);
if (retlen)
*retlen = 0;
/* sanity checks */
if (!len)
return(0);
if (to + len > flash->mtd.size)
return -EINVAL;
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] = OPCODE_PP;
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);
if (retlen)
*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;
if (retlen)
*retlen = 0;
/* sanity checks */
if (!len)
return 0;
if (to + len > flash->mtd.size)
return -EINVAL;
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;
}
/****************************************************************************/
/*
* 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 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, \
.addr_width = 3, \
.flags = (_flags), \
})
#define CAT25_INFO(_sector_size, _n_sectors, _page_size, _addr_width) \
((kernel_ulong_t)&(struct flash_info) { \
.sector_size = (_sector_size), \
.n_sectors = (_n_sectors), \
.page_size = (_page_size), \
.addr_width = (_addr_width), \
.flags = M25P_NO_ERASE, \
})
/* 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) },
{ "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(0x1f4701, 0, 64 * 1024, 64, SECT_4K) },
/* Macronix */
{ "mx25l3205d", INFO(0xc22016, 0, 64 * 1024, 64, 0) },
{ "mx25l6405d", INFO(0xc22017, 0, 64 * 1024, 128, 0) },
{ "mx25l12805d", INFO(0xc22018, 0, 64 * 1024, 256, 0) },
{ "mx25l12855e", INFO(0xc22618, 0, 64 * 1024, 256, 0) },
/* Spansion -- single (large) sector size only, at least
* for the chips listed here (without boot sectors).
*/
{ "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) },
{ "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) },
/* SST -- large erase sizes are "overlays", "sectors" are 4K */
{ "sst25vf040b", INFO(0xbf258d, 0, 64 * 1024, 8, SECT_4K) },
{ "sst25vf080b", INFO(0xbf258e, 0, 64 * 1024, 16, SECT_4K) },
{ "sst25vf016b", INFO(0xbf2541, 0, 64 * 1024, 32, SECT_4K) },
{ "sst25vf032b", INFO(0xbf254a, 0, 64 * 1024, 64, SECT_4K) },
{ "sst25wf512", INFO(0xbf2501, 0, 64 * 1024, 1, SECT_4K) },
{ "sst25wf010", INFO(0xbf2502, 0, 64 * 1024, 2, SECT_4K) },
{ "sst25wf020", INFO(0xbf2503, 0, 64 * 1024, 4, SECT_4K) },
{ "sst25wf040", INFO(0xbf2504, 0, 64 * 1024, 8, SECT_4K) },
/* 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) },
{ "m45pe10", INFO(0x204011, 0, 64 * 1024, 2, 0) },
{ "m45pe80", INFO(0x204014, 0, 64 * 1024, 16, 0) },
{ "m45pe16", INFO(0x204015, 0, 64 * 1024, 32, 0) },
{ "m25pe80", INFO(0x208014, 0, 64 * 1024, 16, 0) },
{ "m25pe16", INFO(0x208015, 0, 64 * 1024, 32, SECT_4K) },
/* 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) },
{ "w25x64", INFO(0xef3017, 0, 64 * 1024, 128, SECT_4K) },
/* Catalyst / On Semiconductor -- non-JEDEC */
{ "cat25c11", CAT25_INFO( 16, 8, 16, 1) },
{ "cat25c03", CAT25_INFO( 32, 8, 16, 2) },
{ "cat25c09", CAT25_INFO( 128, 8, 32, 2) },
{ "cat25c17", CAT25_INFO( 256, 8, 32, 2) },
{ "cat25128", CAT25_INFO(2048, 8, 64, 2) },
{ },
};
MODULE_DEVICE_TABLE(spi, m25p_ids);
static const struct spi_device_id *__devinit 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) {
DEBUG(MTD_DEBUG_LEVEL0, "%s: error %d reading JEDEC ID\n",
dev_name(&spi->dev), tmp);
return NULL;
}
jedec = id[0];
jedec = jedec << 8;
jedec |= id[1];
jedec = jedec << 8;
jedec |= id[2];
/*
* Some chips (like Numonyx M25P80) have JEDEC and non-JEDEC variants,
* which depend on technology process. Officially RDID command doesn't
* exist for non-JEDEC chips, but for compatibility they return ID 0.
*/
if (jedec == 0)
return NULL;
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)
continue;
return &m25p_ids[tmp];
}
}
return NULL;
}
/*
* 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 __devinit 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;
/* 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 = spi->dev.platform_data;
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 (plat_id)
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 (!jid) {
dev_info(&spi->dev, "non-JEDEC variant of %s\n",
id->name);
} 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 = kzalloc(sizeof *flash, GFP_KERNEL);
if (!flash)
return -ENOMEM;
flash->command = kmalloc(MAX_CMD_SIZE + FAST_READ_DUMMY_BYTE, GFP_KERNEL);
if (!flash->command) {
kfree(flash);
return -ENOMEM;
}
flash->spi = spi;
mutex_init(&flash->lock);
dev_set_drvdata(&spi->dev, flash);
/*
* Atmel and SST serial flash tend to power
* up with the software protection bits set
*/
if (info->jedec_id >> 16 == 0x1f ||
info->jedec_id >> 16 == 0xbf) {
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;
/* sst flash chips use AAI word program */
if (info->jedec_id >> 16 == 0xbf)
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 {
flash->erase_opcode = OPCODE_SE;
flash->mtd.erasesize = info->sector_size;
}
if (info->flags & M25P_NO_ERASE)
flash->mtd.flags |= MTD_NO_ERASE;
flash->mtd.dev.parent = &spi->dev;
flash->page_size = info->page_size;
flash->addr_width = info->addr_width;
dev_info(&spi->dev, "%s (%lld Kbytes)\n", id->name,
(long long)flash->mtd.size >> 10);
DEBUG(MTD_DEBUG_LEVEL2,
"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++)
DEBUG(MTD_DEBUG_LEVEL2,
"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).
*/
if (mtd_has_partitions()) {
struct mtd_partition *parts = NULL;
int nr_parts = 0;
if (mtd_has_cmdlinepart()) {
static const char *part_probes[]
= { "cmdlinepart", NULL, };
nr_parts = parse_mtd_partitions(&flash->mtd,
part_probes, &parts, 0);
}
if (nr_parts <= 0 && data && data->parts) {
parts = data->parts;
nr_parts = data->nr_parts;
}
if (nr_parts > 0) {
for (i = 0; i < nr_parts; i++) {
DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
"{.name = %s, .offset = 0x%llx, "
".size = 0x%llx (%lldKiB) }\n",
i, parts[i].name,
(long long)parts[i].offset,
(long long)parts[i].size,
(long long)(parts[i].size >> 10));
}
flash->partitioned = 1;
return add_mtd_partitions(&flash->mtd, parts, nr_parts);
}
} else if (data && data->nr_parts)
dev_warn(&spi->dev, "ignoring %d default partitions on %s\n",
data->nr_parts, data->name);
return add_mtd_device(&flash->mtd) == 1 ? -ENODEV : 0;
}
static int __devexit m25p_remove(struct spi_device *spi)
{
struct m25p *flash = dev_get_drvdata(&spi->dev);
int status;
/* Clean up MTD stuff. */
if (mtd_has_partitions() && flash->partitioned)
status = del_mtd_partitions(&flash->mtd);
else
status = del_mtd_device(&flash->mtd);
if (status == 0) {
kfree(flash->command);
kfree(flash);
}
return 0;
}
static struct spi_driver m25p80_driver = {
.driver = {
.name = "m25p80",
.bus = &spi_bus_type,
.owner = THIS_MODULE,
},
.id_table = m25p_ids,
.probe = m25p_probe,
.remove = __devexit_p(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...
*/
};
static int __init m25p80_init(void)
{
return spi_register_driver(&m25p80_driver);
}
static void __exit m25p80_exit(void)
{
spi_unregister_driver(&m25p80_driver);
}
module_init(m25p80_init);
module_exit(m25p80_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mike Lavender");
MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");
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