[PATCH 3/3] mtd: m25p80: Add support for CAT25xxx serial EEPROMs
Anton Vorontsov
avorontsov at ru.mvista.com
Mon Oct 12 12:24:40 EDT 2009
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.
Signed-off-by: Anton Vorontsov <avorontsov at ru.mvista.com>
---
drivers/mtd/devices/m25p80.c | 114 +++++++++++++++++++++++++----------------
1 files changed, 69 insertions(+), 45 deletions(-)
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 3c74c3a..d3a27d7 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -29,9 +29,6 @@
#include <linux/spi/spi.h>
#include <linux/spi/flash.h>
-
-#define FLASH_PAGESIZE 256
-
/* Flash opcodes. */
#define OPCODE_WREN 0x06 /* Write enable */
#define OPCODE_RDSR 0x05 /* Read status register */
@@ -61,7 +58,7 @@
/* 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 CMD_SIZE 4
+#define MAX_CMD_SIZE 4
#ifdef CONFIG_M25PXX_USE_FAST_READ
#define OPCODE_READ OPCODE_FAST_READ
@@ -78,8 +75,10 @@ struct m25p {
struct mutex lock;
struct mtd_info mtd;
unsigned partitioned:1;
+ u16 page_size;
+ u16 addr_width;
u8 erase_opcode;
- u8 command[CMD_SIZE + FAST_READ_DUMMY_BYTE];
+ u8 command[MAX_CMD_SIZE + FAST_READ_DUMMY_BYTE];
};
static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd)
@@ -198,6 +197,19 @@ static int erase_chip(struct m25p *flash)
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.
@@ -219,11 +231,9 @@ static int erase_sector(struct m25p *flash, u32 offset)
/* Set up command buffer. */
flash->command[0] = flash->erase_opcode;
- flash->command[1] = offset >> 16;
- flash->command[2] = offset >> 8;
- flash->command[3] = offset;
+ m25p_addr2cmd(flash, offset, flash->command);
- spi_write(flash->spi, flash->command, CMD_SIZE);
+ spi_write(flash->spi, flash->command, m25p_cmdsz(flash));
return 0;
}
@@ -325,7 +335,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len,
* Should add 1 byte DUMMY_BYTE.
*/
t[0].tx_buf = flash->command;
- t[0].len = CMD_SIZE + FAST_READ_DUMMY_BYTE;
+ t[0].len = m25p_cmdsz(flash) + FAST_READ_DUMMY_BYTE;
spi_message_add_tail(&t[0], &m);
t[1].rx_buf = buf;
@@ -352,13 +362,11 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len,
/* 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;
+ m25p_addr2cmd(flash, from, flash->command);
spi_sync(flash->spi, &m);
- *retlen = m.actual_length - CMD_SIZE - FAST_READ_DUMMY_BYTE;
+ *retlen = m.actual_length - m25p_cmdsz(flash) - FAST_READ_DUMMY_BYTE;
mutex_unlock(&flash->lock);
@@ -396,7 +404,7 @@ static int m25p80_write(struct mtd_info *mtd, loff_t to, size_t len,
memset(t, 0, (sizeof t));
t[0].tx_buf = flash->command;
- t[0].len = CMD_SIZE;
+ t[0].len = m25p_cmdsz(flash);
spi_message_add_tail(&t[0], &m);
t[1].tx_buf = buf;
@@ -414,41 +422,36 @@ static int m25p80_write(struct mtd_info *mtd, loff_t to, size_t len,
/* 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;
+ m25p_addr2cmd(flash, to, flash->command);
- /* what page do we start with? */
- page_offset = to % FLASH_PAGESIZE;
+ page_offset = to & (flash->page_size - 1);
/* do all the bytes fit onto one page? */
- if (page_offset + len <= FLASH_PAGESIZE) {
+ if (page_offset + len <= flash->page_size) {
t[1].len = len;
spi_sync(flash->spi, &m);
- *retlen = m.actual_length - CMD_SIZE;
+ *retlen = m.actual_length - m25p_cmdsz(flash);
} else {
u32 i;
/* the size of data remaining on the first page */
- page_size = FLASH_PAGESIZE - page_offset;
+ page_size = flash->page_size - page_offset;
t[1].len = page_size;
spi_sync(flash->spi, &m);
- *retlen = m.actual_length - CMD_SIZE;
+ *retlen = m.actual_length - m25p_cmdsz(flash);
- /* write everything in PAGESIZE chunks */
+ /* write everything in flash->page_size chunks */
for (i = page_size; i < len; i += page_size) {
page_size = len - i;
- if (page_size > FLASH_PAGESIZE)
- page_size = FLASH_PAGESIZE;
+ if (page_size > flash->page_size)
+ page_size = flash->page_size;
/* write the next page to flash */
- flash->command[1] = (to + i) >> 16;
- flash->command[2] = (to + i) >> 8;
- flash->command[3] = (to + i);
+ m25p_addr2cmd(flash, to + i, flash->command);
t[1].tx_buf = buf + i;
t[1].len = page_size;
@@ -460,7 +463,7 @@ static int m25p80_write(struct mtd_info *mtd, loff_t to, size_t len,
spi_sync(flash->spi, &m);
if (retlen)
- *retlen += m.actual_length - CMD_SIZE;
+ *retlen += m.actual_length - m25p_cmdsz(flash);
}
}
@@ -492,7 +495,7 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
memset(t, 0, (sizeof t));
t[0].tx_buf = flash->command;
- t[0].len = CMD_SIZE;
+ t[0].len = m25p_cmdsz(flash);
spi_message_add_tail(&t[0], &m);
t[1].tx_buf = buf;
@@ -511,9 +514,7 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
/* Start write from odd address. */
if (actual) {
flash->command[0] = OPCODE_BP;
- flash->command[1] = to >> 16;
- flash->command[2] = to >> 8;
- flash->command[3] = to;
+ m25p_addr2cmd(flash, to, flash->command);
/* write one byte. */
t[1].len = 1;
@@ -521,17 +522,15 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
ret = wait_till_ready(flash);
if (ret)
goto time_out;
- *retlen += m.actual_length - CMD_SIZE;
+ *retlen += m.actual_length - m25p_cmdsz(flash);
}
to += actual;
flash->command[0] = OPCODE_AAI_WP;
- flash->command[1] = to >> 16;
- flash->command[2] = to >> 8;
- flash->command[3] = to;
+ m25p_addr2cmd(flash, to, flash->command);
/* Write out most of the data here. */
- cmd_sz = CMD_SIZE;
+ cmd_sz = m25p_cmdsz(flash);
for (; actual < len - 1; actual += 2) {
t[0].len = cmd_sz;
/* write two bytes. */
@@ -555,10 +554,8 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
if (actual != len) {
write_enable(flash);
flash->command[0] = OPCODE_BP;
- flash->command[1] = to >> 16;
- flash->command[2] = to >> 8;
- flash->command[3] = to;
- t[0].len = CMD_SIZE;
+ m25p_addr2cmd(flash, to, flash->command);
+ t[0].len = m25p_cmdsz(flash);
t[1].len = 1;
t[1].tx_buf = buf + actual;
@@ -566,7 +563,7 @@ static int sst_write(struct mtd_info *mtd, loff_t to, size_t len,
ret = wait_till_ready(flash);
if (ret)
goto time_out;
- *retlen += m.actual_length - CMD_SIZE;
+ *retlen += m.actual_length - m25p_cmdsz(flash);
write_disable(flash);
}
@@ -595,8 +592,12 @@ struct flash_info {
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) \
@@ -605,9 +606,20 @@ struct flash_info {
.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.
@@ -680,6 +692,13 @@ static const struct spi_device_id m25p_ids[] = {
{ "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);
@@ -835,7 +854,12 @@ static int __devinit m25p_probe(struct spi_device *spi)
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);
--
1.6.3.3
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