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-rw-r--r--drivers/i2c/chips/Kconfig43
-rw-r--r--drivers/i2c/chips/Makefile1
-rw-r--r--drivers/i2c/chips/at24.c583
-rw-r--r--drivers/i2c/chips/eeprom.c81
-rw-r--r--drivers/i2c/chips/max6875.c4
-rw-r--r--drivers/i2c/chips/pca9539.c25
-rw-r--r--drivers/i2c/chips/pcf8574.c25
-rw-r--r--drivers/i2c/chips/pcf8591.c33
8 files changed, 701 insertions, 94 deletions
diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig
index 2da2edfa68e..50e0a465374 100644
--- a/drivers/i2c/chips/Kconfig
+++ b/drivers/i2c/chips/Kconfig
@@ -14,6 +14,32 @@ config DS1682
This driver can also be built as a module. If so, the module
will be called ds1682.
+config AT24
+ tristate "EEPROMs from most vendors"
+ depends on SYSFS && EXPERIMENTAL
+ help
+ Enable this driver to get read/write support to most I2C EEPROMs,
+ after you configure the driver to know about each EEPROM on
+ your target board. Use these generic chip names, instead of
+ vendor-specific ones like at24c64 or 24lc02:
+
+ 24c00, 24c01, 24c02, spd (readonly 24c02), 24c04, 24c08,
+ 24c16, 24c32, 24c64, 24c128, 24c256, 24c512, 24c1024
+
+ Unless you like data loss puzzles, always be sure that any chip
+ you configure as a 24c32 (32 kbit) or larger is NOT really a
+ 24c16 (16 kbit) or smaller, and vice versa. Marking the chip
+ as read-only won't help recover from this. Also, if your chip
+ has any software write-protect mechanism you may want to review the
+ code to make sure this driver won't turn it on by accident.
+
+ If you use this with an SMBus adapter instead of an I2C adapter,
+ full functionality is not available. Only smaller devices are
+ supported (24c16 and below, max 4 kByte).
+
+ This driver can also be built as a module. If so, the module
+ will be called at24.
+
config SENSORS_EEPROM
tristate "EEPROM reader"
depends on EXPERIMENTAL
@@ -26,8 +52,8 @@ config SENSORS_EEPROM
will be called eeprom.
config SENSORS_PCF8574
- tristate "Philips PCF8574 and PCF8574A"
- depends on EXPERIMENTAL
+ tristate "Philips PCF8574 and PCF8574A (DEPRECATED)"
+ depends on EXPERIMENTAL && GPIO_PCF857X = "n"
default n
help
If you say yes here you get support for Philips PCF8574 and
@@ -36,12 +62,16 @@ config SENSORS_PCF8574
This driver can also be built as a module. If so, the module
will be called pcf8574.
+ This driver is deprecated and will be dropped soon. Use
+ drivers/gpio/pcf857x.c instead.
+
These devices are hard to detect and rarely found on mainstream
hardware. If unsure, say N.
config PCF8575
- tristate "Philips PCF8575"
+ tristate "Philips PCF8575 (DEPRECATED)"
default n
+ depends on GPIO_PCF857X = "n"
help
If you say yes here you get support for Philips PCF8575 chip.
This chip is a 16-bit I/O expander for the I2C bus. Several other
@@ -50,12 +80,15 @@ config PCF8575
This driver can also be built as a module. If so, the module
will be called pcf8575.
+ This driver is deprecated and will be dropped soon. Use
+ drivers/gpio/pcf857x.c instead.
+
This device is hard to detect and is rarely found on mainstream
hardware. If unsure, say N.
config SENSORS_PCA9539
tristate "Philips PCA9539 16-bit I/O port (DEPRECATED)"
- depends on EXPERIMENTAL && GPIO_PCA9539 = "n"
+ depends on EXPERIMENTAL && GPIO_PCA953X = "n"
help
If you say yes here you get support for the Philips PCA9539
16-bit I/O port.
@@ -64,7 +97,7 @@ config SENSORS_PCA9539
will be called pca9539.
This driver is deprecated and will be dropped soon. Use
- drivers/gpio/pca9539.c instead.
+ drivers/gpio/pca953x.c instead.
config SENSORS_PCF8591
tristate "Philips PCF8591"
diff --git a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile
index e47aca0ca5a..39e3e69ed12 100644
--- a/drivers/i2c/chips/Makefile
+++ b/drivers/i2c/chips/Makefile
@@ -10,6 +10,7 @@
#
obj-$(CONFIG_DS1682) += ds1682.o
+obj-$(CONFIG_AT24) += at24.o
obj-$(CONFIG_SENSORS_EEPROM) += eeprom.o
obj-$(CONFIG_SENSORS_MAX6875) += max6875.o
obj-$(CONFIG_SENSORS_PCA9539) += pca9539.o
diff --git a/drivers/i2c/chips/at24.c b/drivers/i2c/chips/at24.c
new file mode 100644
index 00000000000..e764c94f3e3
--- /dev/null
+++ b/drivers/i2c/chips/at24.c
@@ -0,0 +1,583 @@
+/*
+ * at24.c - handle most I2C EEPROMs
+ *
+ * Copyright (C) 2005-2007 David Brownell
+ * Copyright (C) 2008 Wolfram Sang, Pengutronix
+ *
+ * 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/mutex.h>
+#include <linux/sysfs.h>
+#include <linux/mod_devicetable.h>
+#include <linux/log2.h>
+#include <linux/bitops.h>
+#include <linux/jiffies.h>
+#include <linux/i2c.h>
+#include <linux/i2c/at24.h>
+
+/*
+ * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.
+ * Differences between different vendor product lines (like Atmel AT24C or
+ * MicroChip 24LC, etc) won't much matter for typical read/write access.
+ * There are also I2C RAM chips, likewise interchangeable. One example
+ * would be the PCF8570, which acts like a 24c02 EEPROM (256 bytes).
+ *
+ * However, misconfiguration can lose data. "Set 16-bit memory address"
+ * to a part with 8-bit addressing will overwrite data. Writing with too
+ * big a page size also loses data. And it's not safe to assume that the
+ * conventional addresses 0x50..0x57 only hold eeproms; a PCF8563 RTC
+ * uses 0x51, for just one example.
+ *
+ * Accordingly, explicit board-specific configuration data should be used
+ * in almost all cases. (One partial exception is an SMBus used to access
+ * "SPD" data for DRAM sticks. Those only use 24c02 EEPROMs.)
+ *
+ * So this driver uses "new style" I2C driver binding, expecting to be
+ * told what devices exist. That may be in arch/X/mach-Y/board-Z.c or
+ * similar kernel-resident tables; or, configuration data coming from
+ * a bootloader.
+ *
+ * Other than binding model, current differences from "eeprom" driver are
+ * that this one handles write access and isn't restricted to 24c02 devices.
+ * It also handles larger devices (32 kbit and up) with two-byte addresses,
+ * which won't work on pure SMBus systems.
+ */
+
+struct at24_data {
+ struct at24_platform_data chip;
+ bool use_smbus;
+
+ /*
+ * Lock protects against activities from other Linux tasks,
+ * but not from changes by other I2C masters.
+ */
+ struct mutex lock;
+ struct bin_attribute bin;
+
+ u8 *writebuf;
+ unsigned write_max;
+ unsigned num_addresses;
+
+ /*
+ * Some chips tie up multiple I2C addresses; dummy devices reserve
+ * them for us, and we'll use them with SMBus calls.
+ */
+ struct i2c_client *client[];
+};
+
+/*
+ * This parameter is to help this driver avoid blocking other drivers out
+ * of I2C for potentially troublesome amounts of time. With a 100 kHz I2C
+ * clock, one 256 byte read takes about 1/43 second which is excessive;
+ * but the 1/170 second it takes at 400 kHz may be quite reasonable; and
+ * at 1 MHz (Fm+) a 1/430 second delay could easily be invisible.
+ *
+ * This value is forced to be a power of two so that writes align on pages.
+ */
+static unsigned io_limit = 128;
+module_param(io_limit, uint, 0);
+MODULE_PARM_DESC(io_limit, "Maximum bytes per I/O (default 128)");
+
+/*
+ * Specs often allow 5 msec for a page write, sometimes 20 msec;
+ * it's important to recover from write timeouts.
+ */
+static unsigned write_timeout = 25;
+module_param(write_timeout, uint, 0);
+MODULE_PARM_DESC(write_timeout, "Time (in ms) to try writes (default 25)");
+
+#define AT24_SIZE_BYTELEN 5
+#define AT24_SIZE_FLAGS 8
+
+#define AT24_BITMASK(x) (BIT(x) - 1)
+
+/* create non-zero magic value for given eeprom parameters */
+#define AT24_DEVICE_MAGIC(_len, _flags) \
+ ((1 << AT24_SIZE_FLAGS | (_flags)) \
+ << AT24_SIZE_BYTELEN | ilog2(_len))
+
+static const struct i2c_device_id at24_ids[] = {
+ /* needs 8 addresses as A0-A2 are ignored */
+ { "24c00", AT24_DEVICE_MAGIC(128 / 8, AT24_FLAG_TAKE8ADDR) },
+ /* old variants can't be handled with this generic entry! */
+ { "24c01", AT24_DEVICE_MAGIC(1024 / 8, 0) },
+ { "24c02", AT24_DEVICE_MAGIC(2048 / 8, 0) },
+ /* spd is a 24c02 in memory DIMMs */
+ { "spd", AT24_DEVICE_MAGIC(2048 / 8,
+ AT24_FLAG_READONLY | AT24_FLAG_IRUGO) },
+ { "24c04", AT24_DEVICE_MAGIC(4096 / 8, 0) },
+ /* 24rf08 quirk is handled at i2c-core */
+ { "24c08", AT24_DEVICE_MAGIC(8192 / 8, 0) },
+ { "24c16", AT24_DEVICE_MAGIC(16384 / 8, 0) },
+ { "24c32", AT24_DEVICE_MAGIC(32768 / 8, AT24_FLAG_ADDR16) },
+ { "24c64", AT24_DEVICE_MAGIC(65536 / 8, AT24_FLAG_ADDR16) },
+ { "24c128", AT24_DEVICE_MAGIC(131072 / 8, AT24_FLAG_ADDR16) },
+ { "24c256", AT24_DEVICE_MAGIC(262144 / 8, AT24_FLAG_ADDR16) },
+ { "24c512", AT24_DEVICE_MAGIC(524288 / 8, AT24_FLAG_ADDR16) },
+ { "24c1024", AT24_DEVICE_MAGIC(1048576 / 8, AT24_FLAG_ADDR16) },
+ { "at24", 0 },
+ { /* END OF LIST */ }
+};
+MODULE_DEVICE_TABLE(i2c, at24_ids);
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * This routine supports chips which consume multiple I2C addresses. It
+ * computes the addressing information to be used for a given r/w request.
+ * Assumes that sanity checks for offset happened at sysfs-layer.
+ */
+static struct i2c_client *at24_translate_offset(struct at24_data *at24,
+ unsigned *offset)
+{
+ unsigned i;
+
+ if (at24->chip.flags & AT24_FLAG_ADDR16) {
+ i = *offset >> 16;
+ *offset &= 0xffff;
+ } else {
+ i = *offset >> 8;
+ *offset &= 0xff;
+ }
+
+ return at24->client[i];
+}
+
+static ssize_t at24_eeprom_read(struct at24_data *at24, char *buf,
+ unsigned offset, size_t count)
+{
+ struct i2c_msg msg[2];
+ u8 msgbuf[2];
+ struct i2c_client *client;
+ int status, i;
+
+ memset(msg, 0, sizeof(msg));
+
+ /*
+ * REVISIT some multi-address chips don't rollover page reads to
+ * the next slave address, so we may need to truncate the count.
+ * Those chips might need another quirk flag.
+ *
+ * If the real hardware used four adjacent 24c02 chips and that
+ * were misconfigured as one 24c08, that would be a similar effect:
+ * one "eeprom" file not four, but larger reads would fail when
+ * they crossed certain pages.
+ */
+
+ /*
+ * Slave address and byte offset derive from the offset. Always
+ * set the byte address; on a multi-master board, another master
+ * may have changed the chip's "current" address pointer.
+ */
+ client = at24_translate_offset(at24, &offset);
+
+ if (count > io_limit)
+ count = io_limit;
+
+ /* Smaller eeproms can work given some SMBus extension calls */
+ if (at24->use_smbus) {
+ if (count > I2C_SMBUS_BLOCK_MAX)
+ count = I2C_SMBUS_BLOCK_MAX;
+ status = i2c_smbus_read_i2c_block_data(client, offset,
+ count, buf);
+ dev_dbg(&client->dev, "smbus read %zd@%d --> %d\n",
+ count, offset, status);
+ return (status < 0) ? -EIO : status;
+ }
+
+ /*
+ * When we have a better choice than SMBus calls, use a combined
+ * I2C message. Write address; then read up to io_limit data bytes.
+ * Note that read page rollover helps us here (unlike writes).
+ * msgbuf is u8 and will cast to our needs.
+ */
+ i = 0;
+ if (at24->chip.flags & AT24_FLAG_ADDR16)
+ msgbuf[i++] = offset >> 8;
+ msgbuf[i++] = offset;
+
+ msg[0].addr = client->addr;
+ msg[0].buf = msgbuf;
+ msg[0].len = i;
+
+ msg[1].addr = client->addr;
+ msg[1].flags = I2C_M_RD;
+ msg[1].buf = buf;
+ msg[1].len = count;
+
+ status = i2c_transfer(client->adapter, msg, 2);
+ dev_dbg(&client->dev, "i2c read %zd@%d --> %d\n",
+ count, offset, status);
+
+ if (status == 2)
+ return count;
+ else if (status >= 0)
+ return -EIO;
+ else
+ return status;
+}
+
+static ssize_t at24_bin_read(struct kobject *kobj, struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct at24_data *at24;
+ ssize_t retval = 0;
+
+ at24 = dev_get_drvdata(container_of(kobj, struct device, kobj));
+
+ if (unlikely(!count))
+ return count;
+
+ /*
+ * Read data from chip, protecting against concurrent updates
+ * from this host, but not from other I2C masters.
+ */
+ mutex_lock(&at24->lock);
+
+ while (count) {
+ ssize_t status;
+
+ status = at24_eeprom_read(at24, buf, off, count);
+ if (status <= 0) {
+ if (retval == 0)
+ retval = status;
+ break;
+ }
+ buf += status;
+ off += status;
+ count -= status;
+ retval += status;
+ }
+
+ mutex_unlock(&at24->lock);
+
+ return retval;
+}
+
+
+/*
+ * REVISIT: export at24_bin{read,write}() to let other kernel code use
+ * eeprom data. For example, it might hold a board's Ethernet address, or
+ * board-specific calibration data generated on the manufacturing floor.
+ */
+
+
+/*
+ * Note that if the hardware write-protect pin is pulled high, the whole
+ * chip is normally write protected. But there are plenty of product
+ * variants here, including OTP fuses and partial chip protect.
+ *
+ * We only use page mode writes; the alternative is sloooow. This routine
+ * writes at most one page.
+ */
+static ssize_t at24_eeprom_write(struct at24_data *at24, char *buf,
+ unsigned offset, size_t count)
+{
+ struct i2c_client *client;
+ struct i2c_msg msg;
+ ssize_t status;
+ unsigned long timeout, write_time;
+ unsigned next_page;
+
+ /* Get corresponding I2C address and adjust offset */
+ client = at24_translate_offset(at24, &offset);
+
+ /* write_max is at most a page */
+ if (count > at24->write_max)
+ count = at24->write_max;
+
+ /* Never roll over backwards, to the start of this page */
+ next_page = roundup(offset + 1, at24->chip.page_size);
+ if (offset + count > next_page)
+ count = next_page - offset;
+
+ /* If we'll use I2C calls for I/O, set up the message */
+ if (!at24->use_smbus) {
+ int i = 0;
+
+ msg.addr = client->addr;
+ msg.flags = 0;
+
+ /* msg.buf is u8 and casts will mask the values */
+ msg.buf = at24->writebuf;
+ if (at24->chip.flags & AT24_FLAG_ADDR16)
+ msg.buf[i++] = offset >> 8;
+
+ msg.buf[i++] = offset;
+ memcpy(&msg.buf[i], buf, count);
+ msg.len = i + count;
+ }
+
+ /*
+ * Writes fail if the previous one didn't complete yet. We may
+ * loop a few times until this one succeeds, waiting at least
+ * long enough for one entire page write to work.
+ */
+ timeout = jiffies + msecs_to_jiffies(write_timeout);
+ do {
+ write_time = jiffies;
+ if (at24->use_smbus) {
+ status = i2c_smbus_write_i2c_block_data(client,
+ offset, count, buf);
+ if (status == 0)
+ status = count;
+ } else {
+ status = i2c_transfer(client->adapter, &msg, 1);
+ if (status == 1)
+ status = count;
+ }
+ dev_dbg(&client->dev, "write %zd@%d --> %zd (%ld)\n",
+ count, offset, status, jiffies);
+
+ if (status == count)
+ return count;
+
+ /* REVISIT: at HZ=100, this is sloooow */
+ msleep(1);
+ } while (time_before(write_time, timeout));
+
+ return -ETIMEDOUT;
+}
+
+static ssize_t at24_bin_write(struct kobject *kobj, struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct at24_data *at24;
+ ssize_t retval = 0;
+
+ at24 = dev_get_drvdata(container_of(kobj, struct device, kobj));
+
+ if (unlikely(!count))
+ return count;
+
+ /*
+ * Write data to chip, protecting against concurrent updates
+ * from this host, but not from other I2C masters.
+ */
+ mutex_lock(&at24->lock);
+
+ while (count) {
+ ssize_t status;
+
+ status = at24_eeprom_write(at24, buf, off, count);
+ if (status <= 0) {
+ if (retval == 0)
+ retval = status;
+ break;
+ }
+ buf += status;
+ off += status;
+ count -= status;
+ retval += status;
+ }
+
+ mutex_unlock(&at24->lock);
+
+ return retval;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ struct at24_platform_data chip;
+ bool writable;
+ bool use_smbus = false;
+ struct at24_data *at24;
+ int err;
+ unsigned i, num_addresses;
+ kernel_ulong_t magic;
+
+ if (client->dev.platform_data) {
+ chip = *(struct at24_platform_data *)client->dev.platform_data;
+ } else {
+ if (!id->driver_data) {
+ err = -ENODEV;
+ goto err_out;
+ }
+ magic = id->driver_data;
+ chip.byte_len = BIT(magic & AT24_BITMASK(AT24_SIZE_BYTELEN));
+ magic >>= AT24_SIZE_BYTELEN;
+ chip.flags = magic & AT24_BITMASK(AT24_SIZE_FLAGS);
+ /*
+ * This is slow, but we can't know all eeproms, so we better
+ * play safe. Specifying custom eeprom-types via platform_data
+ * is recommended anyhow.
+ */
+ chip.page_size = 1;
+ }
+
+ if (!is_power_of_2(chip.byte_len))
+ dev_warn(&client->dev,
+ "byte_len looks suspicious (no power of 2)!\n");
+ if (!is_power_of_2(chip.page_size))
+ dev_warn(&client->dev,
+ "page_size looks suspicious (no power of 2)!\n");
+
+ /* Use I2C operations unless we're stuck with SMBus extensions. */
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ if (chip.flags & AT24_FLAG_ADDR16) {
+ err = -EPFNOSUPPORT;
+ goto err_out;
+ }
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
+ err = -EPFNOSUPPORT;
+ goto err_out;
+ }
+ use_smbus = true;
+ }
+
+ if (chip.flags & AT24_FLAG_TAKE8ADDR)
+ num_addresses = 8;
+ else
+ num_addresses = DIV_ROUND_UP(chip.byte_len,
+ (chip.flags & AT24_FLAG_ADDR16) ? 65536 : 256);
+
+ at24 = kzalloc(sizeof(struct at24_data) +
+ num_addresses * sizeof(struct i2c_client *), GFP_KERNEL);
+ if (!at24) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+
+ mutex_init(&at24->lock);
+ at24->use_smbus = use_smbus;
+ at24->chip = chip;
+ at24->num_addresses = num_addresses;
+
+ /*
+ * Export the EEPROM bytes through sysfs, since that's convenient.
+ * By default, only root should see the data (maybe passwords etc)
+ */
+ at24->bin.attr.name = "eeprom";
+ at24->bin.attr.mode = chip.flags & AT24_FLAG_IRUGO ? S_IRUGO : S_IRUSR;
+ at24->bin.attr.owner = THIS_MODULE;
+ at24->bin.read = at24_bin_read;
+ at24->bin.size = chip.byte_len;
+
+ writable = !(chip.flags & AT24_FLAG_READONLY);
+ if (writable) {
+ if (!use_smbus || i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
+
+ unsigned write_max = chip.page_size;
+
+ at24->bin.write = at24_bin_write;
+ at24->bin.attr.mode |= S_IWUSR;
+
+ if (write_max > io_limit)
+ write_max = io_limit;
+ if (use_smbus && write_max > I2C_SMBUS_BLOCK_MAX)
+ write_max = I2C_SMBUS_BLOCK_MAX;
+ at24->write_max = write_max;
+
+ /* buffer (data + address at the beginning) */
+ at24->writebuf = kmalloc(write_max + 2, GFP_KERNEL);
+ if (!at24->writebuf) {
+ err = -ENOMEM;
+ goto err_struct;
+ }
+ } else {
+ dev_warn(&client->dev,
+ "cannot write due to controller restrictions.");
+ }
+ }
+
+ at24->client[0] = client;
+
+ /* use dummy devices for multiple-address chips */
+ for (i = 1; i < num_addresses; i++) {
+ at24->client[i] = i2c_new_dummy(client->adapter,
+ client->addr + i);
+ if (!at24->client[i]) {
+ dev_err(&client->dev, "address 0x%02x unavailable\n",
+ client->addr + i);
+ err = -EADDRINUSE;
+ goto err_clients;
+ }
+ }
+
+ err = sysfs_create_bin_file(&client->dev.kobj, &at24->bin);
+ if (err)
+ goto err_clients;
+
+ i2c_set_clientdata(client, at24);
+
+ dev_info(&client->dev, "%Zd byte %s EEPROM %s\n",
+ at24->bin.size, client->name,
+ writable ? "(writable)" : "(read-only)");
+ dev_dbg(&client->dev,
+ "page_size %d, num_addresses %d, write_max %d%s\n",
+ chip.page_size, num_addresses,
+ at24->write_max,
+ use_smbus ? ", use_smbus" : "");
+
+ return 0;
+
+err_clients:
+ for (i = 1; i < num_addresses; i++)
+ if (at24->client[i])
+ i2c_unregister_device(at24->client[i]);
+
+ kfree(at24->writebuf);
+err_struct:
+ kfree(at24);
+err_out:
+ dev_dbg(&client->dev, "probe error %d\n", err);
+ return err;
+}
+
+static int __devexit at24_remove(struct i2c_client *client)
+{
+ struct at24_data *at24;
+ int i;
+
+ at24 = i2c_get_clientdata(client);
+ sysfs_remove_bin_file(&client->dev.kobj, &at24->bin);
+
+ for (i = 1; i < at24->num_addresses; i++)
+ i2c_unregister_device(at24->client[i]);
+
+ kfree(at24->writebuf);
+ kfree(at24);
+ i2c_set_clientdata(client, NULL);
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static struct i2c_driver at24_driver = {
+ .driver = {
+ .name = "at24",
+ .owner = THIS_MODULE,
+ },
+ .probe = at24_probe,
+ .remove = __devexit_p(at24_remove),
+ .id_table = at24_ids,
+};
+
+static int __init at24_init(void)
+{
+ io_limit = rounddown_pow_of_two(io_limit);
+ return i2c_add_driver(&at24_driver);
+}
+module_init(at24_init);
+
+static void __exit at24_exit(void)
+{
+ i2c_del_driver(&at24_driver);
+}
+module_exit(at24_exit);
+
+MODULE_DESCRIPTION("Driver for most I2C EEPROMs");
+MODULE_AUTHOR("David Brownell and Wolfram Sang");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/chips/eeprom.c b/drivers/i2c/chips/eeprom.c
index 7dee001e513..373ea8d8fe8 100644
--- a/drivers/i2c/chips/eeprom.c
+++ b/drivers/i2c/chips/eeprom.c
@@ -1,15 +1,9 @@
/*
- eeprom.c - Part of lm_sensors, Linux kernel modules for hardware
- monitoring
Copyright (C) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and
Philip Edelbrock <phil@netroedge.com>
Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
Copyright (C) 2003 IBM Corp.
-
- 2004-01-16 Jean Delvare <khali@linux-fr.org>
- Divide the eeprom in 32-byte (arbitrary) slices. This significantly
- speeds sensors up, as well as various scripts using the eeprom
- module.
+ Copyright (C) 2004 Jean Delvare <khali@linux-fr.org>
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
@@ -78,7 +72,7 @@ static struct i2c_driver eeprom_driver = {
static void eeprom_update_client(struct i2c_client *client, u8 slice)
{
struct eeprom_data *data = i2c_get_clientdata(client);
- int i, j;
+ int i;
mutex_lock(&data->update_lock);
@@ -93,15 +87,12 @@ static void eeprom_update_client(struct i2c_client *client, u8 slice)
!= 32)
goto exit;
} else {
- if (i2c_smbus_write_byte(client, slice << 5)) {
- dev_dbg(&client->dev, "eeprom read start has failed!\n");
- goto exit;
- }
- for (i = slice << 5; i < (slice + 1) << 5; i++) {
- j = i2c_smbus_read_byte(client);
- if (j < 0)
+ for (i = slice << 5; i < (slice + 1) << 5; i += 2) {
+ int word = i2c_smbus_read_word_data(client, i);
+ if (word < 0)
goto exit;
- data->data[i] = (u8) j;
+ data->data[i] = word & 0xff;
+ data->data[i + 1] = word >> 8;
}
}
data->last_updated[slice] = jiffies;
@@ -159,24 +150,33 @@ static struct bin_attribute eeprom_attr = {
static int eeprom_attach_adapter(struct i2c_adapter *adapter)
{
+ if (!(adapter->class & (I2C_CLASS_DDC | I2C_CLASS_SPD)))
+ return 0;
return i2c_probe(adapter, &addr_data, eeprom_detect);
}
/* This function is called by i2c_probe */
static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind)
{
- struct i2c_client *new_client;
+ struct i2c_client *client;
struct eeprom_data *data;
int err = 0;
- /* There are three ways we can read the EEPROM data:
+ /* EDID EEPROMs are often 24C00 EEPROMs, which answer to all
+ addresses 0x50-0x57, but we only care about 0x50. So decline
+ attaching to addresses >= 0x51 on DDC buses */
+ if (!(adapter->class & I2C_CLASS_SPD) && address >= 0x51)
+ goto exit;
+
+ /* There are four ways we can read the EEPROM data:
(1) I2C block reads (faster, but unsupported by most adapters)
- (2) Consecutive byte reads (100% overhead)
- (3) Regular byte data reads (200% overhead)
- The third method is not implemented by this driver because all
- known adapters support at least the second. */
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA
- | I2C_FUNC_SMBUS_BYTE))
+ (2) Word reads (128% overhead)
+ (3) Consecutive byte reads (88% overhead, unsafe)
+ (4) Regular byte data reads (265% overhead)
+ The third and fourth methods are not implemented by this driver
+ because all known adapters support one of the first two. */
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)
+ && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK))
goto exit;
if (!(data = kzalloc(sizeof(struct eeprom_data), GFP_KERNEL))) {
@@ -184,50 +184,49 @@ static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind)
goto exit;
}
- new_client = &data->client;
+ client = &data->client;
memset(data->data, 0xff, EEPROM_SIZE);
- i2c_set_clientdata(new_client, data);
- new_client->addr = address;
- new_client->adapter = adapter;
- new_client->driver = &eeprom_driver;
- new_client->flags = 0;
+ i2c_set_clientdata(client, data);
+ client->addr = address;
+ client->adapter = adapter;
+ client->driver = &eeprom_driver;
/* Fill in the remaining client fields */
- strlcpy(new_client->name, "eeprom", I2C_NAME_SIZE);
- data->valid = 0;
+ strlcpy(client->name, "eeprom", I2C_NAME_SIZE);
mutex_init(&data->update_lock);
data->nature = UNKNOWN;
/* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(new_client)))
+ if ((err = i2c_attach_client(client)))
goto exit_kfree;
/* Detect the Vaio nature of EEPROMs.
We use the "PCG-" or "VGN-" prefix as the signature. */
- if (address == 0x57) {
+ if (address == 0x57
+ && i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
char name[4];
- name[0] = i2c_smbus_read_byte_data(new_client, 0x80);
- name[1] = i2c_smbus_read_byte(new_client);
- name[2] = i2c_smbus_read_byte(new_client);
- name[3] = i2c_smbus_read_byte(new_client);
+ name[0] = i2c_smbus_read_byte_data(client, 0x80);
+ name[1] = i2c_smbus_read_byte_data(client, 0x81);
+ name[2] = i2c_smbus_read_byte_data(client, 0x82);
+ name[3] = i2c_smbus_read_byte_data(client, 0x83);
if (!memcmp(name, "PCG-", 4) || !memcmp(name, "VGN-", 4)) {
- dev_info(&new_client->dev, "Vaio EEPROM detected, "
+ dev_info(&client->dev, "Vaio EEPROM detected, "
"enabling privacy protection\n");
data->nature = VAIO;
}
}
/* create the sysfs eeprom file */
- err = sysfs_create_bin_file(&new_client->dev.kobj, &eeprom_attr);
+ err = sysfs_create_bin_file(&client->dev.kobj, &eeprom_attr);
if (err)
goto exit_detach;
return 0;
exit_detach:
- i2c_detach_client(new_client);
+ i2c_detach_client(client);
exit_kfree:
kfree(data);
exit:
diff --git a/drivers/i2c/chips/max6875.c b/drivers/i2c/chips/max6875.c
index cf507b3f60f..5a0285d8b6f 100644
--- a/drivers/i2c/chips/max6875.c
+++ b/drivers/i2c/chips/max6875.c
@@ -170,7 +170,7 @@ static int max6875_detect(struct i2c_adapter *adapter, int address, int kind)
struct i2c_client *real_client;
struct i2c_client *fake_client;
struct max6875_data *data;
- int err = 0;
+ int err;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE_DATA
| I2C_FUNC_SMBUS_READ_BYTE))
@@ -195,7 +195,6 @@ static int max6875_detect(struct i2c_adapter *adapter, int address, int kind)
real_client->addr = address;
real_client->adapter = adapter;
real_client->driver = &max6875_driver;
- real_client->flags = 0;
strlcpy(real_client->name, "max6875", I2C_NAME_SIZE);
mutex_init(&data->update_lock);
@@ -204,7 +203,6 @@ static int max6875_detect(struct i2c_adapter *adapter, int address, int kind)
fake_client->addr = address | 1;
fake_client->adapter = adapter;
fake_client->driver = &max6875_driver;
- fake_client->flags = 0;
strlcpy(fake_client->name, "max6875 subclient", I2C_NAME_SIZE);
if ((err = i2c_attach_client(real_client)) != 0)
diff --git a/drivers/i2c/chips/pca9539.c b/drivers/i2c/chips/pca9539.c
index f43c4e79b55..58ab7f26be2 100644
--- a/drivers/i2c/chips/pca9539.c
+++ b/drivers/i2c/chips/pca9539.c
@@ -113,7 +113,7 @@ static int pca9539_attach_adapter(struct i2c_adapter *adapter)
/* This function is called by i2c_probe */
static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind)
{
- struct i2c_client *new_client;
+ struct i2c_client *client;
struct pca9539_data *data;
int err = 0;
@@ -127,29 +127,28 @@ static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind)
goto exit;
}
- new_client = &data->client;
- i2c_set_clientdata(new_client, data);
- new_client->addr = address;
- new_client->adapter = adapter;
- new_client->driver = &pca9539_driver;
- new_client->flags = 0;
+ client = &data->client;
+ i2c_set_clientdata(client, data);
+ client->addr = address;
+ client->adapter = adapter;
+ client->driver = &pca9539_driver;
if (kind < 0) {
/* Detection: the pca9539 only has 8 registers (0-7).
A read of 7 should succeed, but a read of 8 should fail. */
- if ((i2c_smbus_read_byte_data(new_client, 7) < 0) ||
- (i2c_smbus_read_byte_data(new_client, 8) >= 0))
+ if ((i2c_smbus_read_byte_data(client, 7) < 0) ||
+ (i2c_smbus_read_byte_data(client, 8) >= 0))
goto exit_kfree;
}
- strlcpy(new_client->name, "pca9539", I2C_NAME_SIZE);
+ strlcpy(client->name, "pca9539", I2C_NAME_SIZE);
/* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(new_client)))
+ if ((err = i2c_attach_client(client)))
goto exit_kfree;
/* Register sysfs hooks */
- err = sysfs_create_group(&new_client->dev.kobj,
+ err = sysfs_create_group(&client->dev.kobj,
&pca9539_defattr_group);
if (err)
goto exit_detach;
@@ -157,7 +156,7 @@ static int pca9539_detect(struct i2c_adapter *adapter, int address, int kind)
return 0;
exit_detach:
- i2c_detach_client(new_client);
+ i2c_detach_client(client);
exit_kfree:
kfree(data);
exit:
diff --git a/drivers/i2c/chips/pcf8574.c b/drivers/i2c/chips/pcf8574.c
index e5b31329b56..1b3db2b3ada 100644
--- a/drivers/i2c/chips/pcf8574.c
+++ b/drivers/i2c/chips/pcf8574.c
@@ -1,6 +1,4 @@
/*
- pcf8574.c - Part of lm_sensors, Linux kernel modules for hardware
- monitoring
Copyright (c) 2000 Frodo Looijaard <frodol@dds.nl>,
Philip Edelbrock <phil@netroedge.com>,
Dan Eaton <dan.eaton@rocketlogix.com>
@@ -129,7 +127,7 @@ static int pcf8574_attach_adapter(struct i2c_adapter *adapter)
/* This function is called by i2c_probe */
static int pcf8574_detect(struct i2c_adapter *adapter, int address, int kind)
{
- struct i2c_client *new_client;
+ struct i2c_client *client;
struct pcf8574_data *data;
int err = 0;
const char *client_name = "";
@@ -144,12 +142,11 @@ static int pcf8574_detect(struct i2c_adapter *adapter, int address, int kind)
goto exit;
}
- new_client = &data->client;
- i2c_set_clientdata(new_client, data);
- new_client->addr = address;
- new_client->adapter = adapter;
- new_client->driver = &pcf8574_driver;
- new_client->flags = 0;
+ client = &data->client;
+ i2c_set_clientdata(client, data);
+ client->addr = address;
+ client->adapter = adapter;
+ client->driver = &pcf8574_driver;
/* Now, we would do the remaining detection. But the PCF8574 is plainly
impossible to detect! Stupid chip. */
@@ -168,23 +165,23 @@ static int pcf8574_detect(struct i2c_adapter *adapter, int address, int kind)
client_name = "pcf8574";
/* Fill in the remaining client fields and put it into the global list */
- strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
+ strlcpy(client->name, client_name, I2C_NAME_SIZE);
/* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(new_client)))
+ if ((err = i2c_attach_client(client)))
goto exit_free;
/* Initialize the PCF8574 chip */
- pcf8574_init_client(new_client);
+ pcf8574_init_client(client);
/* Register sysfs hooks */
- err = sysfs_create_group(&new_client->dev.kobj, &pcf8574_attr_group);
+ err = sysfs_create_group(&client->dev.kobj, &pcf8574_attr_group);
if (err)
goto exit_detach;
return 0;
exit_detach:
- i2c_detach_client(new_client);
+ i2c_detach_client(client);
exit_free:
kfree(data);
exit:
diff --git a/drivers/i2c/chips/pcf8591.c b/drivers/i2c/chips/pcf8591.c
index 66c7c3bb942..db735379f22 100644
--- a/drivers/i2c/chips/pcf8591.c
+++ b/drivers/i2c/chips/pcf8591.c
@@ -1,6 +1,4 @@
/*
- pcf8591.c - Part of lm_sensors, Linux kernel modules for hardware
- monitoring
Copyright (C) 2001-2004 Aurelien Jarno <aurelien@aurel32.net>
Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
the help of Jean Delvare <khali@linux-fr.org>
@@ -190,7 +188,7 @@ static int pcf8591_attach_adapter(struct i2c_adapter *adapter)
/* This function is called by i2c_probe */
static int pcf8591_detect(struct i2c_adapter *adapter, int address, int kind)
{
- struct i2c_client *new_client;
+ struct i2c_client *client;
struct pcf8591_data *data;
int err = 0;
@@ -205,12 +203,11 @@ static int pcf8591_detect(struct i2c_adapter *adapter, int address, int kind)
goto exit;
}
- new_client = &data->client;
- i2c_set_clientdata(new_client, data);
- new_client->addr = address;
- new_client->adapter = adapter;
- new_client->driver = &pcf8591_driver;
- new_client->flags = 0;
+ client = &data->client;
+ i2c_set_clientdata(client, data);
+ client->addr = address;
+ client->adapter = adapter;
+ client->driver = &pcf8591_driver;
/* Now, we would do the remaining detection. But the PCF8591 is plainly
impossible to detect! Stupid chip. */
@@ -221,31 +218,31 @@ static int pcf8591_detect(struct i2c_adapter *adapter, int address, int kind)
/* Fill in the remaining client fields and put it into the global
list */
- strlcpy(new_client->name, "pcf8591", I2C_NAME_SIZE);
+ strlcpy(client->name, "pcf8591", I2C_NAME_SIZE);
mutex_init(&data->update_lock);
/* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(new_client)))
+ if ((err = i2c_attach_client(client)))
goto exit_kfree;
/* Initialize the PCF8591 chip */
- pcf8591_init_client(new_client);
+ pcf8591_init_client(client);
/* Register sysfs hooks */
- err = sysfs_create_group(&new_client->dev.kobj, &pcf8591_attr_group);
+ err = sysfs_create_group(&client->dev.kobj, &pcf8591_attr_group);
if (err)
goto exit_detach;
/* Register input2 if not in "two differential inputs" mode */
if (input_mode != 3) {
- if ((err = device_create_file(&new_client->dev,
+ if ((err = device_create_file(&client->dev,
&dev_attr_in2_input)))
goto exit_sysfs_remove;
}
/* Register input3 only in "four single ended inputs" mode */
if (input_mode == 0) {
- if ((err = device_create_file(&new_client->dev,
+ if ((err = device_create_file(&client->dev,
&dev_attr_in3_input)))
goto exit_sysfs_remove;
}
@@ -253,10 +250,10 @@ static int pcf8591_detect(struct i2c_adapter *adapter, int address, int kind)
return 0;
exit_sysfs_remove:
- sysfs_remove_group(&new_client->dev.kobj, &pcf8591_attr_group_opt);
- sysfs_remove_group(&new_client->dev.kobj, &pcf8591_attr_group);
+ sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group_opt);
+ sysfs_remove_group(&client->dev.kobj, &pcf8591_attr_group);
exit_detach:
- i2c_detach_client(new_client);
+ i2c_detach_client(client);
exit_kfree:
kfree(data);
exit: