mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 20:53:53 +08:00
0d73adc14e
The 24RF08 corruption prevention in the eeprom and max6875 drivers wasn't complete. For one thing, the additional quick write should happen as soon as possible and unconditionally, while both drivers had error paths before. For another, when a given chip is forced, the core does not emit a quick write, so a second quick write would cause the corruption rather than prevent it. I plan to move the corruption prevention in the core in the long run, so that individual drivers don't have to care anymore. But I need to merge i2c_probe and i2c_detect before I do (work in progress). Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
263 lines
7.3 KiB
C
263 lines
7.3 KiB
C
/*
|
|
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.
|
|
|
|
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/sched.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/i2c-sensor.h>
|
|
|
|
/* Addresses to scan */
|
|
static unsigned short normal_i2c[] = { 0x50, 0x51, 0x52, 0x53, 0x54,
|
|
0x55, 0x56, 0x57, I2C_CLIENT_END };
|
|
static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
|
|
|
|
/* Insmod parameters */
|
|
SENSORS_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 i2c_client client;
|
|
struct semaphore 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 int eeprom_attach_adapter(struct i2c_adapter *adapter);
|
|
static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind);
|
|
static int eeprom_detach_client(struct i2c_client *client);
|
|
|
|
/* This is the driver that will be inserted */
|
|
static struct i2c_driver eeprom_driver = {
|
|
.owner = THIS_MODULE,
|
|
.name = "eeprom",
|
|
.id = I2C_DRIVERID_EEPROM,
|
|
.flags = I2C_DF_NOTIFY,
|
|
.attach_adapter = eeprom_attach_adapter,
|
|
.detach_client = eeprom_detach_client,
|
|
};
|
|
|
|
static void eeprom_update_client(struct i2c_client *client, u8 slice)
|
|
{
|
|
struct eeprom_data *data = i2c_get_clientdata(client);
|
|
int i, j;
|
|
|
|
down(&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 += I2C_SMBUS_I2C_BLOCK_MAX)
|
|
if (i2c_smbus_read_i2c_block_data(client, i, data->data + i) != I2C_SMBUS_I2C_BLOCK_MAX)
|
|
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)
|
|
goto exit;
|
|
data->data[i] = (u8) j;
|
|
}
|
|
}
|
|
data->last_updated[slice] = jiffies;
|
|
data->valid |= (1 << slice);
|
|
}
|
|
exit:
|
|
up(&data->update_lock);
|
|
}
|
|
|
|
static ssize_t eeprom_read(struct kobject *kobj, 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 security settings to regular users (16 first bytes) */
|
|
if (data->nature == VAIO && off < 16 && !capable(CAP_SYS_ADMIN)) {
|
|
size_t in_row1 = 16 - off;
|
|
in_row1 = min(in_row1, count);
|
|
memset(buf, 0, in_row1);
|
|
if (count - in_row1 > 0)
|
|
memcpy(buf + in_row1, &data->data[16], count - in_row1);
|
|
} else {
|
|
memcpy(buf, &data->data[off], count);
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
static struct bin_attribute eeprom_attr = {
|
|
.attr = {
|
|
.name = "eeprom",
|
|
.mode = S_IRUGO,
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.size = EEPROM_SIZE,
|
|
.read = eeprom_read,
|
|
};
|
|
|
|
static int eeprom_attach_adapter(struct i2c_adapter *adapter)
|
|
{
|
|
return i2c_detect(adapter, &addr_data, eeprom_detect);
|
|
}
|
|
|
|
/* This function is called by i2c_detect */
|
|
int eeprom_detect(struct i2c_adapter *adapter, int address, int kind)
|
|
{
|
|
struct i2c_client *new_client;
|
|
struct eeprom_data *data;
|
|
int err = 0;
|
|
|
|
/* prevent 24RF08 corruption */
|
|
if (kind < 0)
|
|
i2c_smbus_xfer(adapter, address, 0, 0, 0,
|
|
I2C_SMBUS_QUICK, NULL);
|
|
|
|
/* There are three 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))
|
|
goto exit;
|
|
|
|
if (!(data = kmalloc(sizeof(struct eeprom_data), GFP_KERNEL))) {
|
|
err = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
memset(data, 0, sizeof(struct eeprom_data));
|
|
|
|
new_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;
|
|
|
|
/* Fill in the remaining client fields */
|
|
strlcpy(new_client->name, "eeprom", I2C_NAME_SIZE);
|
|
data->valid = 0;
|
|
init_MUTEX(&data->update_lock);
|
|
data->nature = UNKNOWN;
|
|
|
|
/* Tell the I2C layer a new client has arrived */
|
|
if ((err = i2c_attach_client(new_client)))
|
|
goto exit_kfree;
|
|
|
|
/* Detect the Vaio nature of EEPROMs.
|
|
We use the "PCG-" prefix as the signature. */
|
|
if (address == 0x57) {
|
|
if (i2c_smbus_read_byte_data(new_client, 0x80) == 'P'
|
|
&& i2c_smbus_read_byte(new_client) == 'C'
|
|
&& i2c_smbus_read_byte(new_client) == 'G'
|
|
&& i2c_smbus_read_byte(new_client) == '-') {
|
|
dev_info(&new_client->dev, "Vaio EEPROM detected, "
|
|
"enabling password protection\n");
|
|
data->nature = VAIO;
|
|
}
|
|
}
|
|
|
|
/* create the sysfs eeprom file */
|
|
sysfs_create_bin_file(&new_client->dev.kobj, &eeprom_attr);
|
|
|
|
return 0;
|
|
|
|
exit_kfree:
|
|
kfree(data);
|
|
exit:
|
|
return err;
|
|
}
|
|
|
|
static int eeprom_detach_client(struct i2c_client *client)
|
|
{
|
|
int err;
|
|
|
|
err = i2c_detach_client(client);
|
|
if (err) {
|
|
dev_err(&client->dev, "Client deregistration failed, client not detached.\n");
|
|
return err;
|
|
}
|
|
|
|
kfree(i2c_get_clientdata(client));
|
|
|
|
return 0;
|
|
}
|
|
|
|
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);
|