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i2c: Move old eeprom driver to /drivers/misc/eeprom

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Update Kconfig text to specify this driver as I2C.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
This commit is contained in:
Wolfram Sang
2009-01-26 21:19:53 +01:00
committed by Jean Delvare
parent 5195e5093b
commit 2e157888f1
5 changed files with 12 additions and 12 deletions
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11
drivers/misc/eeprom/Kconfig
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@ -26,4 +26,15 @@ config AT24
This driver can also be built as a module. If so, the module
will be called at24.
config SENSORS_EEPROM
tristate "Old I2C EEPROM reader"
depends on I2C && EXPERIMENTAL
help
If you say yes here you get read-only access to the EEPROM data
available on modern memory DIMMs and Sony Vaio laptops via I2C. Such
EEPROMs could theoretically be available on other devices as well.
This driver can also be built as a module. If so, the module
will be called eeprom.
endmenu

1
drivers/misc/eeprom/Makefile
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@ -1 +1,2 @@
obj-$(CONFIG_AT24) += at24.o
obj-$(CONFIG_SENSORS_EEPROM) += eeprom.o

257
drivers/misc/eeprom/eeprom.c Normal file
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@ -0,0 +1,257 @@
/*
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.
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
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x50, 0x51, 0x52, 0x53, 0x54,
0x55, 0x56, 0x57, I2C_CLIENT_END };
/* Insmod parameters */
I2C_CLIENT_INSMOD_1(eeprom);
/* Size of EEPROM in bytes */
#define EEPROM_SIZE 256
/* possible types of eeprom devices */
enum eeprom_nature {
UNKNOWN,
VAIO,
};
/* Each client has this additional data */
struct eeprom_data {
struct mutex update_lock;
u8 valid; /* bitfield, bit!=0 if slice is valid */
unsigned long last_updated[8]; /* In jiffies, 8 slices */
u8 data[EEPROM_SIZE]; /* Register values */
enum eeprom_nature nature;
};
static void eeprom_update_client(struct i2c_client *client, u8 slice)
{
struct eeprom_data *data = i2c_get_clientdata(client);
int i;
mutex_lock(&data->update_lock);
if (!(data->valid & (1 << slice)) ||
time_after(jiffies, data->last_updated[slice] + 300 * HZ)) {
dev_dbg(&client->dev, "Starting eeprom update, slice %u\n", slice);
if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
for (i = slice << 5; i < (slice + 1) << 5; i += 32)
if (i2c_smbus_read_i2c_block_data(client, i,
32, data->data + i)
!= 32)
goto exit;
} else {
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] = word & 0xff;
data->data[i + 1] = word >> 8;
}
}
data->last_updated[slice] = jiffies;
data->valid |= (1 << slice);
}
exit:
mutex_unlock(&data->update_lock);
}
static ssize_t eeprom_read(struct kobject *kobj, struct bin_attribute *bin_attr,
char *buf, loff_t off, size_t count)
{
struct i2c_client *client = to_i2c_client(container_of(kobj, struct device, kobj));
struct eeprom_data *data = i2c_get_clientdata(client);
u8 slice;
if (off > EEPROM_SIZE)
return 0;
if (off + count > EEPROM_SIZE)
count = EEPROM_SIZE - off;
/* Only refresh slices which contain requested bytes */
for (slice = off >> 5; slice <= (off + count - 1) >> 5; slice++)
eeprom_update_client(client, slice);
/* Hide Vaio private settings to regular users:
- BIOS passwords: bytes 0x00 to 0x0f
- UUID: bytes 0x10 to 0x1f
- Serial number: 0xc0 to 0xdf */
if (data->nature == VAIO && !capable(CAP_SYS_ADMIN)) {
int i;
for (i = 0; i < count; i++) {
if ((off + i <= 0x1f) ||
(off + i >= 0xc0 && off + i <= 0xdf))
buf[i] = 0;
else
buf[i] = data->data[off + i];
}
} else {
memcpy(buf, &data->data[off], count);
}
return count;
}
static struct bin_attribute eeprom_attr = {
.attr = {
.name = "eeprom",
.mode = S_IRUGO,
},
.size = EEPROM_SIZE,
.read = eeprom_read,
};
/* Return 0 if detection is successful, -ENODEV otherwise */
static int eeprom_detect(struct i2c_client *client, int kind,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
/* 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) && client->addr >= 0x51)
return -ENODEV;
/* There are four ways we can read the EEPROM data:
(1) I2C block reads (faster, but unsupported by most adapters)
(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))
return -ENODEV;
strlcpy(info->type, "eeprom", I2C_NAME_SIZE);
return 0;
}
static int eeprom_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adapter = client->adapter;
struct eeprom_data *data;
int err;
if (!(data = kzalloc(sizeof(struct eeprom_data), GFP_KERNEL))) {
err = -ENOMEM;
goto exit;
}
memset(data->data, 0xff, EEPROM_SIZE);
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
data->nature = UNKNOWN;
/* Detect the Vaio nature of EEPROMs.
We use the "PCG-" or "VGN-" prefix as the signature. */
if (client->addr == 0x57
&& i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
char name[4];
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(&client->dev, "Vaio EEPROM detected, "
"enabling privacy protection\n");
data->nature = VAIO;
}
}
/* create the sysfs eeprom file */
err = sysfs_create_bin_file(&client->dev.kobj, &eeprom_attr);
if (err)
goto exit_kfree;
return 0;
exit_kfree:
kfree(data);
exit:
return err;
}
static int eeprom_remove(struct i2c_client *client)
{
sysfs_remove_bin_file(&client->dev.kobj, &eeprom_attr);
kfree(i2c_get_clientdata(client));
return 0;
}
static const struct i2c_device_id eeprom_id[] = {
{ "eeprom", 0 },
{ }
};
static struct i2c_driver eeprom_driver = {
.driver = {
.name = "eeprom",
},
.probe = eeprom_probe,
.remove = eeprom_remove,
.id_table = eeprom_id,
.class = I2C_CLASS_DDC | I2C_CLASS_SPD,
.detect = eeprom_detect,
.address_data = &addr_data,
};
static int __init eeprom_init(void)
{
return i2c_add_driver(&eeprom_driver);
}
static void __exit eeprom_exit(void)
{
i2c_del_driver(&eeprom_driver);
}
MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
"Philip Edelbrock <phil@netroedge.com> and "
"Greg Kroah-Hartman <greg@kroah.com>");
MODULE_DESCRIPTION("I2C EEPROM driver");
MODULE_LICENSE("GPL");
module_init(eeprom_init);
module_exit(eeprom_exit);