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-rw-r--r--drivers/mtd/devices/Kconfig17
-rw-r--r--drivers/mtd/devices/Makefile2
-rw-r--r--drivers/mtd/devices/doc2000.c2
-rw-r--r--drivers/mtd/devices/doc2001.c2
-rw-r--r--drivers/mtd/devices/doc2001plus.c2
-rw-r--r--drivers/mtd/devices/m25p80.c582
-rw-r--r--drivers/mtd/devices/mtd_dataflash.c629
7 files changed, 1233 insertions, 3 deletions
diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
index 9a2aa4033c6a..dd628cb51e31 100644
--- a/drivers/mtd/devices/Kconfig
+++ b/drivers/mtd/devices/Kconfig
@@ -47,6 +47,22 @@ config MTD_MS02NV
accelerator. Say Y here if you have a DECstation 5000/2x0 or a
DECsystem 5900 equipped with such a module.
+config MTD_DATAFLASH
+ tristate "Support for AT45xxx DataFlash"
+ depends on MTD && SPI_MASTER && EXPERIMENTAL
+ help
+ This enables access to AT45xxx DataFlash chips, using SPI.
+ Sometimes DataFlash chips are packaged inside MMC-format
+ cards; at this writing, the MMC stack won't handle those.
+
+config MTD_M25P80
+ tristate "Support for M25 SPI Flash"
+ depends on MTD && SPI_MASTER && EXPERIMENTAL
+ help
+ This enables access to ST M25P80 and similar SPI flash chips,
+ used for program and data storage. Set up your spi devices
+ with the right board-specific platform data.
+
config MTD_SLRAM
tristate "Uncached system RAM"
depends on MTD
@@ -202,6 +218,7 @@ config MTD_DOC2001PLUS
config MTD_DOCPROBE
tristate
select MTD_DOCECC
+ select OBSOLETE_INTERMODULE
config MTD_DOCECC
tristate
diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile
index e38db348057d..7c5ed2178380 100644
--- a/drivers/mtd/devices/Makefile
+++ b/drivers/mtd/devices/Makefile
@@ -23,3 +23,5 @@ obj-$(CONFIG_MTD_MTDRAM) += mtdram.o
obj-$(CONFIG_MTD_LART) += lart.o
obj-$(CONFIG_MTD_BLKMTD) += blkmtd.o
obj-$(CONFIG_MTD_BLOCK2MTD) += block2mtd.o
+obj-$(CONFIG_MTD_DATAFLASH) += mtd_dataflash.o
+obj-$(CONFIG_MTD_M25P80) += m25p80.o
diff --git a/drivers/mtd/devices/doc2000.c b/drivers/mtd/devices/doc2000.c
index be5e88b3888d..e4345cf744a2 100644
--- a/drivers/mtd/devices/doc2000.c
+++ b/drivers/mtd/devices/doc2000.c
@@ -138,7 +138,7 @@ static inline int DoC_WaitReady(struct DiskOnChip *doc)
bypass the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
-static inline int DoC_Command(struct DiskOnChip *doc, unsigned char command,
+static int DoC_Command(struct DiskOnChip *doc, unsigned char command,
unsigned char xtraflags)
{
void __iomem *docptr = doc->virtadr;
diff --git a/drivers/mtd/devices/doc2001.c b/drivers/mtd/devices/doc2001.c
index fcb28a6fd89f..681a9c73a2a3 100644
--- a/drivers/mtd/devices/doc2001.c
+++ b/drivers/mtd/devices/doc2001.c
@@ -103,7 +103,7 @@ static inline int DoC_WaitReady(void __iomem * docptr)
with the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
-static inline void DoC_Command(void __iomem * docptr, unsigned char command,
+static void DoC_Command(void __iomem * docptr, unsigned char command,
unsigned char xtraflags)
{
/* Assert the CLE (Command Latch Enable) line to the flash chip */
diff --git a/drivers/mtd/devices/doc2001plus.c b/drivers/mtd/devices/doc2001plus.c
index 0595cc7324b2..5f57f29efee4 100644
--- a/drivers/mtd/devices/doc2001plus.c
+++ b/drivers/mtd/devices/doc2001plus.c
@@ -118,7 +118,7 @@ static inline void DoC_CheckASIC(void __iomem * docptr)
/* DoC_Command: Send a flash command to the flash chip through the Flash
* command register. Need 2 Write Pipeline Terminates to complete send.
*/
-static inline void DoC_Command(void __iomem * docptr, unsigned char command,
+static void DoC_Command(void __iomem * docptr, unsigned char command,
unsigned char xtraflags)
{
WriteDOC(command, docptr, Mplus_FlashCmd);
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
new file mode 100644
index 000000000000..d5f24089be71
--- /dev/null
+++ b/drivers/mtd/devices/m25p80.c
@@ -0,0 +1,582 @@
+/*
+ * MTD SPI driver for ST M25Pxx 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/interrupt.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/flash.h>
+
+#include <asm/semaphore.h>
+
+
+/* NOTE: AT 25F and SST 25LF series are very similar,
+ * but commands for sector erase and chip id differ...
+ */
+
+#define FLASH_PAGESIZE 256
+
+/* Flash opcodes. */
+#define OPCODE_WREN 6 /* Write enable */
+#define OPCODE_RDSR 5 /* Read status register */
+#define OPCODE_READ 3 /* Read data bytes */
+#define OPCODE_PP 2 /* Page program */
+#define OPCODE_SE 0xd8 /* Sector erase */
+#define OPCODE_RES 0xab /* Read Electronic Signature */
+#define OPCODE_RDID 0x9f /* Read JEDEC ID */
+
+/* Status Register bits. */
+#define SR_WIP 1 /* Write in progress */
+#define SR_WEL 2 /* Write enable latch */
+#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_COUNT 100000
+
+
+#ifdef CONFIG_MTD_PARTITIONS
+#define mtd_has_partitions() (1)
+#else
+#define mtd_has_partitions() (0)
+#endif
+
+/****************************************************************************/
+
+struct m25p {
+ struct spi_device *spi;
+ struct semaphore lock;
+ struct mtd_info mtd;
+ unsigned partitioned;
+ u8 command[4];
+};
+
+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;
+}
+
+
+/*
+ * 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);
+}
+
+
+/*
+ * Service routine to read status register until ready, or timeout occurs.
+ * Returns non-zero if error.
+ */
+static int wait_till_ready(struct m25p *flash)
+{
+ int count;
+ int sr;
+
+ /* one chip guarantees max 5 msec wait here after page writes,
+ * but potentially three seconds (!) after page erase.
+ */
+ for (count = 0; count < MAX_READY_WAIT_COUNT; count++) {
+ if ((sr = read_sr(flash)) < 0)
+ break;
+ else if (!(sr & SR_WIP))
+ return 0;
+
+ /* REVISIT sometimes sleeping would be best */
+ }
+
+ return 1;
+}
+
+
+/*
+ * 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 at 0x%08x\n", flash->spi->dev.bus_id,
+ __FUNCTION__, 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] = OPCODE_SE;
+ flash->command[1] = offset >> 16;
+ flash->command[2] = offset >> 8;
+ flash->command[3] = offset;
+
+ spi_write(flash->spi, flash->command, sizeof(flash->command));
+
+ 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;
+
+ DEBUG(MTD_DEBUG_LEVEL2, "%s: %s %s 0x%08x, len %zd\n",
+ flash->spi->dev.bus_id, __FUNCTION__, "at",
+ (u32)instr->addr, instr->len);
+
+ /* sanity checks */
+ if (instr->addr + instr->len > flash->mtd.size)
+ return -EINVAL;
+ if ((instr->addr % mtd->erasesize) != 0
+ || (instr->len % mtd->erasesize) != 0) {
+ return -EINVAL;
+ }
+
+ addr = instr->addr;
+ len = instr->len;
+
+ down(&flash->lock);
+
+ /* now erase those sectors */
+ while (len) {
+ if (erase_sector(flash, addr)) {
+ instr->state = MTD_ERASE_FAILED;
+ up(&flash->lock);
+ return -EIO;
+ }
+
+ addr += mtd->erasesize;
+ len -= mtd->erasesize;
+ }
+
+ up(&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",
+ flash->spi->dev.bus_id, __FUNCTION__, "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));
+
+ t[0].tx_buf = flash->command;
+ t[0].len = sizeof(flash->command);
+ 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;
+
+ down(&flash->lock);
+
+ /* Wait till previous write/erase is done. */
+ if (wait_till_ready(flash)) {
+ /* REVISIT status return?? */
+ up(&flash->lock);
+ return 1;
+ }
+
+ /* NOTE: OPCODE_FAST_READ (if available) is faster... */
+
+ /* Set up the write data buffer. */
+ flash->command[0] = OPCODE_READ;
+ flash->command[1] = from >> 16;
+ flash->command[2] = from >> 8;
+ flash->command[3] = from;
+
+ spi_sync(flash->spi, &m);
+
+ *retlen = m.actual_length - sizeof(flash->command);
+
+ up(&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",
+ flash->spi->dev.bus_id, __FUNCTION__, "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 = sizeof(flash->command);
+ spi_message_add_tail(&t[0], &m);
+
+ t[1].tx_buf = buf;
+ spi_message_add_tail(&t[1], &m);
+
+ down(&flash->lock);
+
+ /* Wait until finished previous write command. */
+ if (wait_till_ready(flash))
+ return 1;
+
+ write_enable(flash);
+
+ /* Set up the opcode in the write buffer. */
+ flash->command[0] = OPCODE_PP;
+ flash->command[1] = to >> 16;
+ flash->command[2] = to >> 8;
+ flash->command[3] = to;
+
+ /* what page do we start with? */
+ page_offset = to % FLASH_PAGESIZE;
+
+ /* do all the bytes fit onto one page? */
+ if (page_offset + len <= FLASH_PAGESIZE) {
+ t[1].len = len;
+
+ spi_sync(flash->spi, &m);
+
+ *retlen = m.actual_length - sizeof(flash->command);
+ } else {
+ u32 i;
+
+ /* the size of data remaining on the first page */
+ page_size = FLASH_PAGESIZE - page_offset;
+
+ t[1].len = page_size;
+ spi_sync(flash->spi, &m);
+
+ *retlen = m.actual_length - sizeof(flash->command);
+
+ /* write everything in PAGESIZE chunks */
+ for (i = page_size; i < len; i += page_size) {
+ page_size = len - i;
+ if (page_size > FLASH_PAGESIZE)
+ page_size = FLASH_PAGESIZE;
+
+ /* write the next page to flash */
+ flash->command[1] = (to + i) >> 16;
+ flash->command[2] = (to + i) >> 8;
+ flash->command[3] = (to + i);
+
+ 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
+ - sizeof(flash->command);
+ }
+ }
+
+ up(&flash->lock);
+
+ return 0;
+}
+
+
+/****************************************************************************/
+
+/*
+ * SPI device driver setup and teardown
+ */
+
+struct flash_info {
+ char *name;
+ u8 id;
+ u16 jedec_id;
+ unsigned sector_size;
+ unsigned n_sectors;
+};
+
+static struct flash_info __devinitdata m25p_data [] = {
+ /* REVISIT: fill in JEDEC ids, for parts that have them */
+ { "m25p05", 0x05, 0x0000, 32 * 1024, 2 },
+ { "m25p10", 0x10, 0x0000, 32 * 1024, 4 },
+ { "m25p20", 0x11, 0x0000, 64 * 1024, 4 },
+ { "m25p40", 0x12, 0x0000, 64 * 1024, 8 },
+ { "m25p80", 0x13, 0x0000, 64 * 1024, 16 },
+ { "m25p16", 0x14, 0x0000, 64 * 1024, 32 },
+ { "m25p32", 0x15, 0x0000, 64 * 1024, 64 },
+ { "m25p64", 0x16, 0x2017, 64 * 1024, 128 },
+};
+
+/*
+ * 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)
+{
+ 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.
+ */
+ data = spi->dev.platform_data;
+ if (!data || !data->type) {
+ /* FIXME some chips can identify themselves with RES
+ * or JEDEC get-id commands. Try them ...
+ */
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: no chip id\n",
+ flash->spi->dev.bus_id);
+ return -ENODEV;
+ }
+
+ for (i = 0, info = m25p_data; i < ARRAY_SIZE(m25p_data); i++, info++) {
+ if (strcmp(data->type, info->name) == 0)
+ break;
+ }
+ if (i == ARRAY_SIZE(m25p_data)) {
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: unrecognized id %s\n",
+ flash->spi->dev.bus_id, data->type);
+ return -ENODEV;
+ }
+
+ flash = kzalloc(sizeof *flash, SLAB_KERNEL);
+ if (!flash)
+ return -ENOMEM;
+
+ flash->spi = spi;
+ init_MUTEX(&flash->lock);
+ dev_set_drvdata(&spi->dev, flash);
+
+ if (data->name)
+ flash->mtd.name = data->name;
+ else
+ flash->mtd.name = spi->dev.bus_id;
+
+ flash->mtd.type = MTD_NORFLASH;
+ flash->mtd.flags = MTD_CAP_NORFLASH;
+ flash->mtd.size = info->sector_size * info->n_sectors;
+ flash->mtd.erasesize = info->sector_size;
+ flash->mtd.erase = m25p80_erase;
+ flash->mtd.read = m25p80_read;
+ flash->mtd.write = m25p80_write;
+
+ dev_info(&spi->dev, "%s (%d Kbytes)\n", info->name,
+ flash->mtd.size / 1024);
+
+ DEBUG(MTD_DEBUG_LEVEL2,
+ "mtd .name = %s, .size = 0x%.8x (%uM) "
+ ".erasesize = 0x%.8x (%uK) .numeraseregions = %d\n",
+ flash->mtd.name,
+ flash->mtd.size, flash->mtd.size / (1024*1024),
+ 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%.8x, "
+ ".erasesize = 0x%.8x (%uK), "
+ ".numblocks = %d }\n",
+ i, 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;
+
+#ifdef CONFIG_MTD_CMDLINE_PARTS
+ static const char *part_probes[] = { "cmdlinepart", NULL, };
+
+ nr_parts = parse_mtd_partitions(&flash->mtd,
+ part_probes, &parts, 0);
+#endif
+
+ if (nr_parts <= 0 && data && data->parts) {
+ parts = data->parts;
+ nr_parts = data->nr_parts;
+ }
+
+ if (nr_parts > 0) {
+ for (i = 0; i < data->nr_parts; i++) {
+ DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
+ "{.name = %s, .offset = 0x%.8x, "
+ ".size = 0x%.8x (%uK) }\n",
+ i, data->parts[i].name,
+ data->parts[i].offset,
+ data->parts[i].size,
+ data->parts[i].size / 1024);
+ }
+ flash->partitioned = 1;
+ return add_mtd_partitions(&flash->mtd, parts, nr_parts);
+ }
+ } else if (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);
+ return 0;
+}
+
+
+static struct spi_driver m25p80_driver = {
+ .driver = {
+ .name = "m25p80",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+ .probe = m25p_probe,
+ .remove = __devexit_p(m25p_remove),
+};
+
+
+static int m25p80_init(void)
+{
+ return spi_register_driver(&m25p80_driver);
+}
+
+
+static void 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");
diff --git a/drivers/mtd/devices/mtd_dataflash.c b/drivers/mtd/devices/mtd_dataflash.c
new file mode 100644
index 000000000000..155737e7483f
--- /dev/null
+++ b/drivers/mtd/devices/mtd_dataflash.c
@@ -0,0 +1,629 @@
+/*
+ * Atmel AT45xxx DataFlash MTD driver for lightweight SPI framework
+ *
+ * Largely derived from at91_dataflash.c:
+ * Copyright (C) 2003-2005 SAN People (Pty) Ltd
+ *
+ * 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/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/flash.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+
+/*
+ * DataFlash is a kind of SPI flash. Most AT45 chips have two buffers in
+ * each chip, which may be used for double buffered I/O; but this driver
+ * doesn't (yet) use these for any kind of i/o overlap or prefetching.
+ *
+ * Sometimes DataFlash is packaged in MMC-format cards, although the
+ * MMC stack can't use SPI (yet), or distinguish between MMC and DataFlash
+ * protocols during enumeration.
+ */
+
+#define CONFIG_DATAFLASH_WRITE_VERIFY
+
+/* reads can bypass the buffers */
+#define OP_READ_CONTINUOUS 0xE8
+#define OP_READ_PAGE 0xD2
+
+/* group B requests can run even while status reports "busy" */
+#define OP_READ_STATUS 0xD7 /* group B */
+
+/* move data between host and buffer */
+#define OP_READ_BUFFER1 0xD4 /* group B */
+#define OP_READ_BUFFER2 0xD6 /* group B */
+#define OP_WRITE_BUFFER1 0x84 /* group B */
+#define OP_WRITE_BUFFER2 0x87 /* group B */
+
+/* erasing flash */
+#define OP_ERASE_PAGE 0x81
+#define OP_ERASE_BLOCK 0x50
+
+/* move data between buffer and flash */
+#define OP_TRANSFER_BUF1 0x53
+#define OP_TRANSFER_BUF2 0x55
+#define OP_MREAD_BUFFER1 0xD4
+#define OP_MREAD_BUFFER2 0xD6
+#define OP_MWERASE_BUFFER1 0x83
+#define OP_MWERASE_BUFFER2 0x86
+#define OP_MWRITE_BUFFER1 0x88 /* sector must be pre-erased */
+#define OP_MWRITE_BUFFER2 0x89 /* sector must be pre-erased */
+
+/* write to buffer, then write-erase to flash */
+#define OP_PROGRAM_VIA_BUF1 0x82
+#define OP_PROGRAM_VIA_BUF2 0x85
+
+/* compare buffer to flash */
+#define OP_COMPARE_BUF1 0x60
+#define OP_COMPARE_BUF2 0x61
+
+/* read flash to buffer, then write-erase to flash */
+#define OP_REWRITE_VIA_BUF1 0x58
+#define OP_REWRITE_VIA_BUF2 0x59
+
+/* newer chips report JEDEC manufacturer and device IDs; chip
+ * serial number and OTP bits; and per-sector writeprotect.
+ */
+#define OP_READ_ID 0x9F
+#define OP_READ_SECURITY 0x77
+#define OP_WRITE_SECURITY 0x9A /* OTP bits */
+
+
+struct dataflash {
+ u8 command[4];
+ char name[24];
+
+ unsigned partitioned:1;
+
+ unsigned short page_offset; /* offset in flash address */
+ unsigned int page_size; /* of bytes per page */
+
+ struct semaphore lock;
+ struct spi_device *spi;
+
+ struct mtd_info mtd;
+};
+
+#ifdef CONFIG_MTD_PARTITIONS
+#define mtd_has_partitions() (1)
+#else
+#define mtd_has_partitions() (0)
+#endif
+
+/* ......................................................................... */
+
+/*
+ * Return the status of the DataFlash device.
+ */
+static inline int dataflash_status(struct spi_device *spi)
+{
+ /* NOTE: at45db321c over 25 MHz wants to write
+ * a dummy byte after the opcode...
+ */
+ return spi_w8r8(spi, OP_READ_STATUS);
+}
+
+/*
+ * Poll the DataFlash device until it is READY.
+ * This usually takes 5-20 msec or so; more for sector erase.
+ */
+static int dataflash_waitready(struct spi_device *spi)
+{
+ int status;
+
+ for (;;) {
+ status = dataflash_status(spi);
+ if (status < 0) {
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: status %d?\n",
+ spi->dev.bus_id, status);
+ status = 0;
+ }
+
+ if (status & (1 << 7)) /* RDY/nBSY */
+ return status;
+
+ msleep(3);
+ }
+}
+
+/* ......................................................................... */
+
+/*
+ * Erase pages of flash.
+ */
+static int dataflash_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+ struct dataflash *priv = (struct dataflash *)mtd->priv;
+ struct spi_device *spi = priv->spi;
+ struct spi_transfer x = { .tx_dma = 0, };
+ struct spi_message msg;
+ unsigned blocksize = priv->page_size << 3;
+ u8 *command;
+
+ DEBUG(MTD_DEBUG_LEVEL2, "%s: erase addr=0x%x len 0x%x\n",
+ spi->dev.bus_id,
+ instr->addr, instr->len);
+
+ /* Sanity checks */
+ if ((instr->addr + instr->len) > mtd->size
+ || (instr->len % priv->page_size) != 0
+ || (instr->addr % priv->page_size) != 0)
+ return -EINVAL;
+
+ spi_message_init(&msg);
+
+ x.tx_buf = command = priv->command;
+ x.len = 4;
+ spi_message_add_tail(&x, &msg);
+
+ down(&priv->lock);
+ while (instr->len > 0) {
+ unsigned int pageaddr;
+ int status;
+ int do_block;
+
+ /* Calculate flash page address; use block erase (for speed) if
+ * we're at a block boundary and need to erase the whole block.
+ */
+ pageaddr = instr->addr / priv->page_size;
+ do_block = (pageaddr & 0x7) == 0 && instr->len <= blocksize;
+ pageaddr = pageaddr << priv->page_offset;
+
+ command[0] = do_block ? OP_ERASE_BLOCK : OP_ERASE_PAGE;
+ command[1] = (u8)(pageaddr >> 16);
+ command[2] = (u8)(pageaddr >> 8);
+ command[3] = 0;
+
+ DEBUG(MTD_DEBUG_LEVEL3, "ERASE %s: (%x) %x %x %x [%i]\n",
+ do_block ? "block" : "page",
+ command[0], command[1], command[2], command[3],
+ pageaddr);
+
+ status = spi_sync(spi, &msg);
+ (void) dataflash_waitready(spi);
+
+ if (status < 0) {
+ printk(KERN_ERR "%s: erase %x, err %d\n",
+ spi->dev.bus_id, pageaddr, status);
+ /* REVISIT: can retry instr->retries times; or
+ * giveup and instr->fail_addr = instr->addr;
+ */
+ continue;
+ }
+
+ if (do_block) {
+ instr->addr += blocksize;
+ instr->len -= blocksize;
+ } else {
+ instr->addr += priv->page_size;
+ instr->len -= priv->page_size;
+ }
+ }
+ up(&priv->lock);
+
+ /* Inform MTD subsystem that erase is complete */
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
+
+ return 0;
+}
+
+/*
+ * Read from the DataFlash device.
+ * from : Start offset in flash device
+ * len : Amount to read
+ * retlen : About of data actually read
+ * buf : Buffer containing the data
+ */
+static int dataflash_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ struct dataflash *priv = (struct dataflash *)mtd->priv;
+ struct spi_transfer x[2] = { { .tx_dma = 0, }, };
+ struct spi_message msg;
+ unsigned int addr;
+ u8 *command;
+ int status;
+
+ DEBUG(MTD_DEBUG_LEVEL2, "%s: read 0x%x..0x%x\n",
+ priv->spi->dev.bus_id, (unsigned)from, (unsigned)(from + len));
+
+ *retlen = 0;
+
+ /* Sanity checks */
+ if (!len)
+ return 0;
+ if (from + len > mtd->size)
+ return -EINVAL;
+
+ /* Calculate flash page/byte address */
+ addr = (((unsigned)from / priv->page_size) << priv->page_offset)
+ + ((unsigned)from % priv->page_size);
+
+ command = priv->command;
+
+ DEBUG(MTD_DEBUG_LEVEL3, "READ: (%x) %x %x %x\n",
+ command[0], command[1], command[2], command[3]);
+
+ spi_message_init(&msg);
+
+ x[0].tx_buf = command;
+ x[0].len = 8;
+ spi_message_add_tail(&x[0], &msg);
+
+ x[1].rx_buf = buf;
+ x[1].len = len;
+ spi_message_add_tail(&x[1], &msg);
+
+ down(&priv->lock);
+
+ /* Continuous read, max clock = f(car) which may be less than
+ * the peak rate available. Some chips support commands with
+ * fewer "don't care" bytes. Both buffers stay unchanged.
+ */
+ command[0] = OP_READ_CONTINUOUS;
+ command[1] = (u8)(addr >> 16);
+ command[2] = (u8)(addr >> 8);
+ command[3] = (u8)(addr >> 0);
+ /* plus 4 "don't care" bytes */
+
+ status = spi_sync(priv->spi, &msg);
+ up(&priv->lock);
+
+ if (status >= 0) {
+ *retlen = msg.actual_length - 8;
+ status = 0;
+ } else
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: read %x..%x --> %d\n",
+ priv->spi->dev.bus_id,
+ (unsigned)from, (unsigned)(from + len),
+ status);
+ return status;
+}
+
+/*
+ * Write to the DataFlash device.
+ * to : Start offset in flash device
+ * len : Amount to write
+ * retlen : Amount of data actually written
+ * buf : Buffer containing the data
+ */
+static int dataflash_write(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t * retlen, const u_char * buf)
+{
+ struct dataflash *priv = (struct dataflash *)mtd->priv;
+ struct spi_device *spi = priv->spi;
+ struct spi_transfer x[2] = { { .tx_dma = 0, }, };
+ struct spi_message msg;
+ unsigned int pageaddr, addr, offset, writelen;
+ size_t remaining = len;
+ u_char *writebuf = (u_char *) buf;
+ int status = -EINVAL;
+ u8 *command;
+
+ DEBUG(MTD_DEBUG_LEVEL2, "%s: write 0x%x..0x%x\n",
+ spi->dev.bus_id, (unsigned)to, (unsigned)(to + len));
+
+ *retlen = 0;
+
+ /* Sanity checks */
+ if (!len)
+ return 0;
+ if ((to + len) > mtd->size)
+ return -EINVAL;
+
+ spi_message_init(&msg);
+
+ x[0].tx_buf = command = priv->command;
+ x[0].len = 4;
+ spi_message_add_tail(&x[0], &msg);
+
+ pageaddr = ((unsigned)to / priv->page_size);
+ offset = ((unsigned)to % priv->page_size);
+ if (offset + len > priv->page_size)
+ writelen = priv->page_size - offset;
+ else
+ writelen = len;
+
+ down(&priv->lock);
+ while (remaining > 0) {
+ DEBUG(MTD_DEBUG_LEVEL3, "write @ %i:%i len=%i\n",
+ pageaddr, offset, writelen);
+
+ /* REVISIT:
+ * (a) each page in a sector must be rewritten at least
+ * once every 10K sibling erase/program operations.
+ * (b) for pages that are already erased, we could
+ * use WRITE+MWRITE not PROGRAM for ~30% speedup.
+ * (c) WRITE to buffer could be done while waiting for
+ * a previous MWRITE/MWERASE to complete ...
+ * (d) error handling here seems to be mostly missing.
+ *
+ * Two persistent bits per page, plus a per-sector counter,
+ * could support (a) and (b) ... we might consider using
+ * the second half of sector zero, which is just one block,
+ * to track that state. (On AT91, that sector should also
+ * support boot-from-DataFlash.)
+ */
+
+ addr = pageaddr << priv->page_offset;
+
+ /* (1) Maybe transfer partial page to Buffer1 */
+ if (writelen != priv->page_size) {
+ command[0] = OP_TRANSFER_BUF1;
+ command[1] = (addr & 0x00FF0000) >> 16;
+ command[2] = (addr & 0x0000FF00) >> 8;
+ command[3] = 0;
+
+ DEBUG(MTD_DEBUG_LEVEL3, "TRANSFER: (%x) %x %x %x\n",
+ command[0], command[1], command[2], command[3]);
+
+ status = spi_sync(spi, &msg);
+ if (status < 0)
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: xfer %u -> %d \n",
+ spi->dev.bus_id, addr, status);
+
+ (void) dataflash_waitready(priv->spi);
+ }
+
+ /* (2) Program full page via Buffer1 */
+ addr += offset;
+ command[0] = OP_PROGRAM_VIA_BUF1;
+ command[1] = (addr & 0x00FF0000) >> 16;
+ command[2] = (addr & 0x0000FF00) >> 8;
+ command[3] = (addr & 0x000000FF);
+
+ DEBUG(MTD_DEBUG_LEVEL3, "PROGRAM: (%x) %x %x %x\n",
+ command[0], command[1], command[2], command[3]);
+
+ x[1].tx_buf = writebuf;
+ x[1].len = writelen;
+ spi_message_add_tail(x + 1, &msg);
+ status = spi_sync(spi, &msg);
+ spi_transfer_del(x + 1);
+ if (status < 0)
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: pgm %u/%u -> %d \n",
+ spi->dev.bus_id, addr, writelen, status);
+
+ (void) dataflash_waitready(priv->spi);
+
+
+#ifdef CONFIG_DATAFLASH_WRITE_VERIFY
+
+ /* (3) Compare to Buffer1 */
+ addr = pageaddr << priv->page_offset;
+ command[0] = OP_COMPARE_BUF1;
+ command[1] = (addr & 0x00FF0000) >> 16;
+ command[2] = (addr & 0x0000FF00) >> 8;
+ command[3] = 0;
+
+ DEBUG(MTD_DEBUG_LEVEL3, "COMPARE: (%x) %x %x %x\n",
+ command[0], command[1], command[2], command[3]);
+
+ status = spi_sync(spi, &msg);
+ if (status < 0)
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: compare %u -> %d \n",
+ spi->dev.bus_id, addr, status);
+
+ status = dataflash_waitready(priv->spi);
+
+ /* Check result of the compare operation */
+ if ((status & (1 << 6)) == 1) {
+ printk(KERN_ERR "%s: compare page %u, err %d\n",
+ spi->dev.bus_id, pageaddr, status);
+ remaining = 0;
+ status = -EIO;
+ break;
+ } else
+ status = 0;
+
+#endif /* CONFIG_DATAFLASH_WRITE_VERIFY */
+
+ remaining = remaining - writelen;
+ pageaddr++;
+ offset = 0;
+ writebuf += writelen;
+ *retlen += writelen;
+
+ if (remaining > priv->page_size)
+ writelen = priv->page_size;
+ else
+ writelen = remaining;
+ }
+ up(&priv->lock);
+
+ return status;
+}
+
+/* ......................................................................... */
+
+/*
+ * Register DataFlash device with MTD subsystem.
+ */
+static int __devinit
+add_dataflash(struct spi_device *spi, char *name,
+ int nr_pages, int pagesize, int pageoffset)
+{
+ struct dataflash *priv;
+ struct mtd_info *device;
+ struct flash_platform_data *pdata = spi->dev.platform_data;
+
+ priv = (struct dataflash *) kzalloc(sizeof *priv, GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ init_MUTEX(&priv->lock);
+ priv->spi = spi;
+ priv->page_size = pagesize;
+ priv->page_offset = pageoffset;
+
+ /* name must be usable with cmdlinepart */
+ sprintf(priv->name, "spi%d.%d-%s",
+ spi->master->bus_num, spi->chip_select,
+ name);
+
+ device = &priv->mtd;
+ device->name = (pdata && pdata->name) ? pdata->name : priv->name;
+ device->size = nr_pages * pagesize;
+ device->erasesize = pagesize;
+ device->owner = THIS_MODULE;
+ device->type = MTD_DATAFLASH;
+ device->flags = MTD_CAP_NORFLASH;
+ device->erase = dataflash_erase;
+ device->read = dataflash_read;
+ device->write = dataflash_write;
+ device->priv = priv;
+
+ dev_info(&spi->dev, "%s (%d KBytes)\n", name, device->size/1024);
+ dev_set_drvdata(&spi->dev, priv);
+
+ if (mtd_has_partitions()) {
+ struct mtd_partition *parts;
+ int nr_parts = 0;
+
+#ifdef CONFIG_MTD_CMDLINE_PARTS
+ static const char *part_probes[] = { "cmdlinepart", NULL, };
+
+ nr_parts = parse_mtd_partitions(device, part_probes, &parts, 0);
+#endif
+
+ if (nr_parts <= 0 && pdata && pdata->parts) {
+ parts = pdata->parts;
+ nr_parts = pdata->nr_parts;
+ }
+
+ if (nr_parts > 0) {
+ priv->partitioned = 1;
+ return add_mtd_partitions(device, parts, nr_parts);
+ }
+ } else if (pdata && pdata->nr_parts)
+ dev_warn(&spi->dev, "ignoring %d default partitions on %s\n",
+ pdata->nr_parts, device->name);
+
+ return add_mtd_device(device) == 1 ? -ENODEV : 0;
+}
+
+/*
+ * Detect and initialize DataFlash device:
+ *
+ * Device Density ID code #Pages PageSize Offset
+ * AT45DB011B 1Mbit (128K) xx0011xx (0x0c) 512 264 9
+ * AT45DB021B 2Mbit (256K) xx0101xx (0x14) 1025 264 9
+ * AT45DB041B 4Mbit (512K) xx0111xx (0x1c) 2048 264 9
+ * AT45DB081B 8Mbit (1M) xx1001xx (0x24) 4096 264 9
+ * AT45DB0161B 16Mbit (2M) xx1011xx (0x2c) 4096 528 10
+ * AT45DB0321B 32Mbit (4M) xx1101xx (0x34) 8192 528 10
+ * AT45DB0642 64Mbit (8M) xx111xxx (0x3c) 8192 1056 11
+ * AT45DB1282 128Mbit (16M) xx0100xx (0x10) 16384 1056 11
+ */
+static int __devinit dataflash_probe(struct spi_device *spi)
+{
+ int status;
+
+ status = dataflash_status(spi);
+ if (status <= 0 || status == 0xff) {
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: status error %d\n",
+ spi->dev.bus_id, status);
+ if (status == 0xff)
+ status = -ENODEV;
+ return status;
+ }
+
+ /* if there's a device there, assume it's dataflash.
+ * board setup should have set spi->max_speed_max to
+ * match f(car) for continuous reads, mode 0 or 3.
+ */
+ switch (status & 0x3c) {
+ case 0x0c: /* 0 0 1 1 x x */
+ status = add_dataflash(spi, "AT45DB011B", 512, 264, 9);
+ break;
+ case 0x14: /* 0 1 0 1 x x */
+ status = add_dataflash(spi, "AT45DB021B", 1025, 264, 9);
+ break;
+ case 0x1c: /* 0 1 1 1 x x */
+ status = add_dataflash(spi, "AT45DB041x", 2048, 264, 9);
+ break;
+ case 0x24: /* 1 0 0 1 x x */
+ status = add_dataflash(spi, "AT45DB081B", 4096, 264, 9);
+ break;
+ case 0x2c: /* 1 0 1 1 x x */
+ status = add_dataflash(spi, "AT45DB161x", 4096, 528, 10);
+ break;
+ case 0x34: /* 1 1 0 1 x x */
+ status = add_dataflash(spi, "AT45DB321x", 8192, 528, 10);
+ break;
+ case 0x38: /* 1 1 1 x x x */
+ case 0x3c:
+ status = add_dataflash(spi, "AT45DB642x", 8192, 1056, 11);
+ break;
+ /* obsolete AT45DB1282 not (yet?) supported */
+ default:
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: unsupported device (%x)\n",
+ spi->dev.bus_id, status & 0x3c);
+ status = -ENODEV;
+ }
+
+ if (status < 0)
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: add_dataflash --> %d\n",
+ spi->dev.bus_id, status);
+
+ return status;
+}
+
+static int __devexit dataflash_remove(struct spi_device *spi)
+{
+ struct dataflash *flash = dev_get_drvdata(&spi->dev);
+ int status;
+
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: remove\n", spi->dev.bus_id);
+
+ if (mtd_has_partitions() && flash->partitioned)
+ status = del_mtd_partitions(&flash->mtd);
+ else
+ status = del_mtd_device(&flash->mtd);
+ if (status == 0)
+ kfree(flash);
+ return status;
+}
+
+static struct spi_driver dataflash_driver = {
+ .driver = {
+ .name = "mtd_dataflash",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+
+ .probe = dataflash_probe,
+ .remove = __devexit_p(dataflash_remove),
+
+ /* FIXME: investigate suspend and resume... */
+};
+
+static int __init dataflash_init(void)
+{
+ return spi_register_driver(&dataflash_driver);
+}
+module_init(dataflash_init);
+
+static void __exit dataflash_exit(void)
+{
+ spi_unregister_driver(&dataflash_driver);
+}
+module_exit(dataflash_exit);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andrew Victor, David Brownell");
+MODULE_DESCRIPTION("MTD DataFlash driver");
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