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authorWolfram Sang <w.sang@pengutronix.de>2009-01-26 21:19:54 +0100
committerJean Delvare <khali@linux-fr.org>2009-01-26 21:19:54 +0100
commite51d565ff6bb1cedc10568425511badf0633a212 (patch)
treec8bd2623f2b925e1c8fb451d022529410f9c3406 /drivers/spi
parent2e157888f132131f8877affd2785dcee4c227c1d (diff)
spi: Move at25 (for SPI eeproms) to /drivers/misc/eeprom
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/Kconfig11
-rw-r--r--drivers/spi/Makefile1
-rw-r--r--drivers/spi/at25.c389
3 files changed, 0 insertions, 401 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 4a6fe01831a..83a185d5296 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -230,17 +230,6 @@ config SPI_XILINX
#
comment "SPI Protocol Masters"
-config SPI_AT25
- tristate "SPI EEPROMs from most vendors"
- depends on SYSFS
- help
- Enable this driver to get read/write support to most SPI EEPROMs,
- after you configure the board init code to know about each eeprom
- on your target board.
-
- This driver can also be built as a module. If so, the module
- will be called at25.
-
config SPI_SPIDEV
tristate "User mode SPI device driver support"
depends on EXPERIMENTAL
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 5e9f521b884..5d0451936d8 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -33,7 +33,6 @@ obj-$(CONFIG_SPI_SH_SCI) += spi_sh_sci.o
# ... add above this line ...
# SPI protocol drivers (device/link on bus)
-obj-$(CONFIG_SPI_AT25) += at25.o
obj-$(CONFIG_SPI_SPIDEV) += spidev.o
obj-$(CONFIG_SPI_TLE62X0) += tle62x0.o
# ... add above this line ...
diff --git a/drivers/spi/at25.c b/drivers/spi/at25.c
deleted file mode 100644
index 290dbe99647..00000000000
--- a/drivers/spi/at25.c
+++ /dev/null
@@ -1,389 +0,0 @@
-/*
- * at25.c -- support most SPI EEPROMs, such as Atmel AT25 models
- *
- * Copyright (C) 2006 David Brownell
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- */
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/sched.h>
-
-#include <linux/spi/spi.h>
-#include <linux/spi/eeprom.h>
-
-
-/*
- * NOTE: this is an *EEPROM* driver. The vagaries of product naming
- * mean that some AT25 products are EEPROMs, and others are FLASH.
- * Handle FLASH chips with the drivers/mtd/devices/m25p80.c driver,
- * not this one!
- */
-
-struct at25_data {
- struct spi_device *spi;
- struct mutex lock;
- struct spi_eeprom chip;
- struct bin_attribute bin;
- unsigned addrlen;
-};
-
-#define AT25_WREN 0x06 /* latch the write enable */
-#define AT25_WRDI 0x04 /* reset the write enable */
-#define AT25_RDSR 0x05 /* read status register */
-#define AT25_WRSR 0x01 /* write status register */
-#define AT25_READ 0x03 /* read byte(s) */
-#define AT25_WRITE 0x02 /* write byte(s)/sector */
-
-#define AT25_SR_nRDY 0x01 /* nRDY = write-in-progress */
-#define AT25_SR_WEN 0x02 /* write enable (latched) */
-#define AT25_SR_BP0 0x04 /* BP for software writeprotect */
-#define AT25_SR_BP1 0x08
-#define AT25_SR_WPEN 0x80 /* writeprotect enable */
-
-
-#define EE_MAXADDRLEN 3 /* 24 bit addresses, up to 2 MBytes */
-
-/* Specs often allow 5 msec for a page write, sometimes 20 msec;
- * it's important to recover from write timeouts.
- */
-#define EE_TIMEOUT 25
-
-/*-------------------------------------------------------------------------*/
-
-#define io_limit PAGE_SIZE /* bytes */
-
-static ssize_t
-at25_ee_read(
- struct at25_data *at25,
- char *buf,
- unsigned offset,
- size_t count
-)
-{
- u8 command[EE_MAXADDRLEN + 1];
- u8 *cp;
- ssize_t status;
- struct spi_transfer t[2];
- struct spi_message m;
-
- cp = command;
- *cp++ = AT25_READ;
-
- /* 8/16/24-bit address is written MSB first */
- switch (at25->addrlen) {
- default: /* case 3 */
- *cp++ = offset >> 16;
- case 2:
- *cp++ = offset >> 8;
- case 1:
- case 0: /* can't happen: for better codegen */
- *cp++ = offset >> 0;
- }
-
- spi_message_init(&m);
- memset(t, 0, sizeof t);
-
- t[0].tx_buf = command;
- t[0].len = at25->addrlen + 1;
- spi_message_add_tail(&t[0], &m);
-
- t[1].rx_buf = buf;
- t[1].len = count;
- spi_message_add_tail(&t[1], &m);
-
- mutex_lock(&at25->lock);
-
- /* Read it all at once.
- *
- * REVISIT that's potentially a problem with large chips, if
- * other devices on the bus need to be accessed regularly or
- * this chip is clocked very slowly
- */
- status = spi_sync(at25->spi, &m);
- dev_dbg(&at25->spi->dev,
- "read %Zd bytes at %d --> %d\n",
- count, offset, (int) status);
-
- mutex_unlock(&at25->lock);
- return status ? status : count;
-}
-
-static ssize_t
-at25_bin_read(struct kobject *kobj, struct bin_attribute *bin_attr,
- char *buf, loff_t off, size_t count)
-{
- struct device *dev;
- struct at25_data *at25;
-
- dev = container_of(kobj, struct device, kobj);
- at25 = dev_get_drvdata(dev);
-
- if (unlikely(off >= at25->bin.size))
- return 0;
- if ((off + count) > at25->bin.size)
- count = at25->bin.size - off;
- if (unlikely(!count))
- return count;
-
- return at25_ee_read(at25, buf, off, count);
-}
-
-
-static ssize_t
-at25_ee_write(struct at25_data *at25, char *buf, loff_t off, size_t count)
-{
- ssize_t status = 0;
- unsigned written = 0;
- unsigned buf_size;
- u8 *bounce;
-
- /* Temp buffer starts with command and address */
- buf_size = at25->chip.page_size;
- if (buf_size > io_limit)
- buf_size = io_limit;
- bounce = kmalloc(buf_size + at25->addrlen + 1, GFP_KERNEL);
- if (!bounce)
- return -ENOMEM;
-
- /* For write, rollover is within the page ... so we write at
- * most one page, then manually roll over to the next page.
- */
- bounce[0] = AT25_WRITE;
- mutex_lock(&at25->lock);
- do {
- unsigned long timeout, retries;
- unsigned segment;
- unsigned offset = (unsigned) off;
- u8 *cp = bounce + 1;
-
- *cp = AT25_WREN;
- status = spi_write(at25->spi, cp, 1);
- if (status < 0) {
- dev_dbg(&at25->spi->dev, "WREN --> %d\n",
- (int) status);
- break;
- }
-
- /* 8/16/24-bit address is written MSB first */
- switch (at25->addrlen) {
- default: /* case 3 */
- *cp++ = offset >> 16;
- case 2:
- *cp++ = offset >> 8;
- case 1:
- case 0: /* can't happen: for better codegen */
- *cp++ = offset >> 0;
- }
-
- /* Write as much of a page as we can */
- segment = buf_size - (offset % buf_size);
- if (segment > count)
- segment = count;
- memcpy(cp, buf, segment);
- status = spi_write(at25->spi, bounce,
- segment + at25->addrlen + 1);
- dev_dbg(&at25->spi->dev,
- "write %u bytes at %u --> %d\n",
- segment, offset, (int) status);
- if (status < 0)
- break;
-
- /* REVISIT this should detect (or prevent) failed writes
- * to readonly sections of the EEPROM...
- */
-
- /* Wait for non-busy status */
- timeout = jiffies + msecs_to_jiffies(EE_TIMEOUT);
- retries = 0;
- do {
- int sr;
-
- sr = spi_w8r8(at25->spi, AT25_RDSR);
- if (sr < 0 || (sr & AT25_SR_nRDY)) {
- dev_dbg(&at25->spi->dev,
- "rdsr --> %d (%02x)\n", sr, sr);
- /* at HZ=100, this is sloooow */
- msleep(1);
- continue;
- }
- if (!(sr & AT25_SR_nRDY))
- break;
- } while (retries++ < 3 || time_before_eq(jiffies, timeout));
-
- if (time_after(jiffies, timeout)) {
- dev_err(&at25->spi->dev,
- "write %d bytes offset %d, "
- "timeout after %u msecs\n",
- segment, offset,
- jiffies_to_msecs(jiffies -
- (timeout - EE_TIMEOUT)));
- status = -ETIMEDOUT;
- break;
- }
-
- off += segment;
- buf += segment;
- count -= segment;
- written += segment;
-
- } while (count > 0);
-
- mutex_unlock(&at25->lock);
-
- kfree(bounce);
- return written ? written : status;
-}
-
-static ssize_t
-at25_bin_write(struct kobject *kobj, struct bin_attribute *bin_attr,
- char *buf, loff_t off, size_t count)
-{
- struct device *dev;
- struct at25_data *at25;
-
- dev = container_of(kobj, struct device, kobj);
- at25 = dev_get_drvdata(dev);
-
- if (unlikely(off >= at25->bin.size))
- return -EFBIG;
- if ((off + count) > at25->bin.size)
- count = at25->bin.size - off;
- if (unlikely(!count))
- return count;
-
- return at25_ee_write(at25, buf, off, count);
-}
-
-/*-------------------------------------------------------------------------*/
-
-static int at25_probe(struct spi_device *spi)
-{
- struct at25_data *at25 = NULL;
- const struct spi_eeprom *chip;
- int err;
- int sr;
- int addrlen;
-
- /* Chip description */
- chip = spi->dev.platform_data;
- if (!chip) {
- dev_dbg(&spi->dev, "no chip description\n");
- err = -ENODEV;
- goto fail;
- }
-
- /* For now we only support 8/16/24 bit addressing */
- if (chip->flags & EE_ADDR1)
- addrlen = 1;
- else if (chip->flags & EE_ADDR2)
- addrlen = 2;
- else if (chip->flags & EE_ADDR3)
- addrlen = 3;
- else {
- dev_dbg(&spi->dev, "unsupported address type\n");
- err = -EINVAL;
- goto fail;
- }
-
- /* Ping the chip ... the status register is pretty portable,
- * unlike probing manufacturer IDs. We do expect that system
- * firmware didn't write it in the past few milliseconds!
- */
- sr = spi_w8r8(spi, AT25_RDSR);
- if (sr < 0 || sr & AT25_SR_nRDY) {
- dev_dbg(&spi->dev, "rdsr --> %d (%02x)\n", sr, sr);
- err = -ENXIO;
- goto fail;
- }
-
- if (!(at25 = kzalloc(sizeof *at25, GFP_KERNEL))) {
- err = -ENOMEM;
- goto fail;
- }
-
- mutex_init(&at25->lock);
- at25->chip = *chip;
- at25->spi = spi_dev_get(spi);
- dev_set_drvdata(&spi->dev, at25);
- at25->addrlen = addrlen;
-
- /* Export the EEPROM bytes through sysfs, since that's convenient.
- * Default to root-only access to the data; EEPROMs often hold data
- * that's sensitive for read and/or write, like ethernet addresses,
- * security codes, board-specific manufacturing calibrations, etc.
- */
- at25->bin.attr.name = "eeprom";
- at25->bin.attr.mode = S_IRUSR;
- at25->bin.read = at25_bin_read;
-
- at25->bin.size = at25->chip.byte_len;
- if (!(chip->flags & EE_READONLY)) {
- at25->bin.write = at25_bin_write;
- at25->bin.attr.mode |= S_IWUSR;
- }
-
- err = sysfs_create_bin_file(&spi->dev.kobj, &at25->bin);
- if (err)
- goto fail;
-
- dev_info(&spi->dev, "%Zd %s %s eeprom%s, pagesize %u\n",
- (at25->bin.size < 1024)
- ? at25->bin.size
- : (at25->bin.size / 1024),
- (at25->bin.size < 1024) ? "Byte" : "KByte",
- at25->chip.name,
- (chip->flags & EE_READONLY) ? " (readonly)" : "",
- at25->chip.page_size);
- return 0;
-fail:
- dev_dbg(&spi->dev, "probe err %d\n", err);
- kfree(at25);
- return err;
-}
-
-static int __devexit at25_remove(struct spi_device *spi)
-{
- struct at25_data *at25;
-
- at25 = dev_get_drvdata(&spi->dev);
- sysfs_remove_bin_file(&spi->dev.kobj, &at25->bin);
- kfree(at25);
- return 0;
-}
-
-/*-------------------------------------------------------------------------*/
-
-static struct spi_driver at25_driver = {
- .driver = {
- .name = "at25",
- .owner = THIS_MODULE,
- },
- .probe = at25_probe,
- .remove = __devexit_p(at25_remove),
-};
-
-static int __init at25_init(void)
-{
- return spi_register_driver(&at25_driver);
-}
-module_init(at25_init);
-
-static void __exit at25_exit(void)
-{
- spi_unregister_driver(&at25_driver);
-}
-module_exit(at25_exit);
-
-MODULE_DESCRIPTION("Driver for most SPI EEPROMs");
-MODULE_AUTHOR("David Brownell");
-MODULE_LICENSE("GPL");
-