https://github.com/torvalds/linux
Tip revision: 606135a3081e045b677cde164a296c51f66c4633 authored by Linus Torvalds on 28 February 2007, 04:59:12 UTC
Linux 2.6.21-rc2
Linux 2.6.21-rc2
Tip revision: 606135a
max1619.c
/*
* max1619.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2003-2004 Alexey Fisher <fishor@mail.ru>
* Jean Delvare <khali@linux-fr.org>
*
* Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
* It reports up to two temperatures (its own plus up to
* one external one). Complete datasheet can be
* obtained from Maxim's website at:
* http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
*
* 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/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a,
0x29, 0x2a, 0x2b,
0x4c, 0x4d, 0x4e,
I2C_CLIENT_END };
/*
* Insmod parameters
*/
I2C_CLIENT_INSMOD_1(max1619);
/*
* The MAX1619 registers
*/
#define MAX1619_REG_R_MAN_ID 0xFE
#define MAX1619_REG_R_CHIP_ID 0xFF
#define MAX1619_REG_R_CONFIG 0x03
#define MAX1619_REG_W_CONFIG 0x09
#define MAX1619_REG_R_CONVRATE 0x04
#define MAX1619_REG_W_CONVRATE 0x0A
#define MAX1619_REG_R_STATUS 0x02
#define MAX1619_REG_R_LOCAL_TEMP 0x00
#define MAX1619_REG_R_REMOTE_TEMP 0x01
#define MAX1619_REG_R_REMOTE_HIGH 0x07
#define MAX1619_REG_W_REMOTE_HIGH 0x0D
#define MAX1619_REG_R_REMOTE_LOW 0x08
#define MAX1619_REG_W_REMOTE_LOW 0x0E
#define MAX1619_REG_R_REMOTE_CRIT 0x10
#define MAX1619_REG_W_REMOTE_CRIT 0x12
#define MAX1619_REG_R_TCRIT_HYST 0x11
#define MAX1619_REG_W_TCRIT_HYST 0x13
/*
* Conversions and various macros
*/
#define TEMP_FROM_REG(val) ((val & 0x80 ? val-0x100 : val) * 1000)
#define TEMP_TO_REG(val) ((val < 0 ? val+0x100*1000 : val) / 1000)
/*
* Functions declaration
*/
static int max1619_attach_adapter(struct i2c_adapter *adapter);
static int max1619_detect(struct i2c_adapter *adapter, int address,
int kind);
static void max1619_init_client(struct i2c_client *client);
static int max1619_detach_client(struct i2c_client *client);
static struct max1619_data *max1619_update_device(struct device *dev);
/*
* Driver data (common to all clients)
*/
static struct i2c_driver max1619_driver = {
.driver = {
.name = "max1619",
},
.attach_adapter = max1619_attach_adapter,
.detach_client = max1619_detach_client,
};
/*
* Client data (each client gets its own)
*/
struct max1619_data {
struct i2c_client client;
struct class_device *class_dev;
struct mutex update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
/* registers values */
u8 temp_input1; /* local */
u8 temp_input2, temp_low2, temp_high2; /* remote */
u8 temp_crit2;
u8 temp_hyst2;
u8 alarms;
};
/*
* Sysfs stuff
*/
#define show_temp(value) \
static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct max1619_data *data = max1619_update_device(dev); \
return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
}
show_temp(temp_input1);
show_temp(temp_input2);
show_temp(temp_low2);
show_temp(temp_high2);
show_temp(temp_crit2);
show_temp(temp_hyst2);
#define set_temp2(value, reg) \
static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
size_t count) \
{ \
struct i2c_client *client = to_i2c_client(dev); \
struct max1619_data *data = i2c_get_clientdata(client); \
long val = simple_strtol(buf, NULL, 10); \
\
mutex_lock(&data->update_lock); \
data->value = TEMP_TO_REG(val); \
i2c_smbus_write_byte_data(client, reg, data->value); \
mutex_unlock(&data->update_lock); \
return count; \
}
set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
{
struct max1619_data *data = max1619_update_device(dev);
return sprintf(buf, "%d\n", data->alarms);
}
static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
set_temp_low2);
static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
set_temp_high2);
static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
set_temp_crit2);
static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
set_temp_hyst2);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
static struct attribute *max1619_attributes[] = {
&dev_attr_temp1_input.attr,
&dev_attr_temp2_input.attr,
&dev_attr_temp2_min.attr,
&dev_attr_temp2_max.attr,
&dev_attr_temp2_crit.attr,
&dev_attr_temp2_crit_hyst.attr,
&dev_attr_alarms.attr,
NULL
};
static const struct attribute_group max1619_group = {
.attrs = max1619_attributes,
};
/*
* Real code
*/
static int max1619_attach_adapter(struct i2c_adapter *adapter)
{
if (!(adapter->class & I2C_CLASS_HWMON))
return 0;
return i2c_probe(adapter, &addr_data, max1619_detect);
}
/*
* The following function does more than just detection. If detection
* succeeds, it also registers the new chip.
*/
static int max1619_detect(struct i2c_adapter *adapter, int address, int kind)
{
struct i2c_client *new_client;
struct max1619_data *data;
int err = 0;
const char *name = "";
u8 reg_config=0, reg_convrate=0, reg_status=0;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
goto exit;
if (!(data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL))) {
err = -ENOMEM;
goto exit;
}
/* The common I2C client data is placed right before the
MAX1619-specific data. */
new_client = &data->client;
i2c_set_clientdata(new_client, data);
new_client->addr = address;
new_client->adapter = adapter;
new_client->driver = &max1619_driver;
new_client->flags = 0;
/*
* Now we do the remaining detection. A negative kind means that
* the driver was loaded with no force parameter (default), so we
* must both detect and identify the chip. A zero kind means that
* the driver was loaded with the force parameter, the detection
* step shall be skipped. A positive kind means that the driver
* was loaded with the force parameter and a given kind of chip is
* requested, so both the detection and the identification steps
* are skipped.
*/
if (kind < 0) { /* detection */
reg_config = i2c_smbus_read_byte_data(new_client,
MAX1619_REG_R_CONFIG);
reg_convrate = i2c_smbus_read_byte_data(new_client,
MAX1619_REG_R_CONVRATE);
reg_status = i2c_smbus_read_byte_data(new_client,
MAX1619_REG_R_STATUS);
if ((reg_config & 0x03) != 0x00
|| reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
dev_dbg(&adapter->dev,
"MAX1619 detection failed at 0x%02x.\n",
address);
goto exit_free;
}
}
if (kind <= 0) { /* identification */
u8 man_id, chip_id;
man_id = i2c_smbus_read_byte_data(new_client,
MAX1619_REG_R_MAN_ID);
chip_id = i2c_smbus_read_byte_data(new_client,
MAX1619_REG_R_CHIP_ID);
if ((man_id == 0x4D) && (chip_id == 0x04))
kind = max1619;
if (kind <= 0) { /* identification failed */
dev_info(&adapter->dev,
"Unsupported chip (man_id=0x%02X, "
"chip_id=0x%02X).\n", man_id, chip_id);
goto exit_free;
}
}
if (kind == max1619)
name = "max1619";
/* We can fill in the remaining client fields */
strlcpy(new_client->name, name, I2C_NAME_SIZE);
data->valid = 0;
mutex_init(&data->update_lock);
/* Tell the I2C layer a new client has arrived */
if ((err = i2c_attach_client(new_client)))
goto exit_free;
/* Initialize the MAX1619 chip */
max1619_init_client(new_client);
/* Register sysfs hooks */
if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
goto exit_detach;
data->class_dev = hwmon_device_register(&new_client->dev);
if (IS_ERR(data->class_dev)) {
err = PTR_ERR(data->class_dev);
goto exit_remove_files;
}
return 0;
exit_remove_files:
sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
exit_detach:
i2c_detach_client(new_client);
exit_free:
kfree(data);
exit:
return err;
}
static void max1619_init_client(struct i2c_client *client)
{
u8 config;
/*
* Start the conversions.
*/
i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
5); /* 2 Hz */
config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
if (config & 0x40)
i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
config & 0xBF); /* run */
}
static int max1619_detach_client(struct i2c_client *client)
{
struct max1619_data *data = i2c_get_clientdata(client);
int err;
hwmon_device_unregister(data->class_dev);
sysfs_remove_group(&client->dev.kobj, &max1619_group);
if ((err = i2c_detach_client(client)))
return err;
kfree(data);
return 0;
}
static struct max1619_data *max1619_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct max1619_data *data = i2c_get_clientdata(client);
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
dev_dbg(&client->dev, "Updating max1619 data.\n");
data->temp_input1 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_LOCAL_TEMP);
data->temp_input2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_TEMP);
data->temp_high2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_HIGH);
data->temp_low2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_LOW);
data->temp_crit2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_REMOTE_CRIT);
data->temp_hyst2 = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_TCRIT_HYST);
data->alarms = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_STATUS);
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
static int __init sensors_max1619_init(void)
{
return i2c_add_driver(&max1619_driver);
}
static void __exit sensors_max1619_exit(void)
{
i2c_del_driver(&max1619_driver);
}
MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
"Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("MAX1619 sensor driver");
MODULE_LICENSE("GPL");
module_init(sensors_max1619_init);
module_exit(sensors_max1619_exit);