https://github.com/torvalds/linux
Tip revision: d770e558e21961ad6cfdf0ff7df0eb5d7d4f0754 authored by Linus Torvalds on 05 July 2015, 18:01:52 UTC
Linux 4.2-rc1
Linux 4.2-rc1
Tip revision: d770e55
max1619.c
/*
* max1619.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net>
* Jean Delvare <jdelvare@suse.de>
*
* 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.
*/
#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/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
static const unsigned short normal_i2c[] = {
0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
/*
* 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
*/
static int temp_from_reg(int val)
{
return (val & 0x80 ? val-0x100 : val) * 1000;
}
static int temp_to_reg(int val)
{
return (val < 0 ? val+0x100*1000 : val) / 1000;
}
enum temp_index {
t_input1 = 0,
t_input2,
t_low2,
t_high2,
t_crit2,
t_hyst2,
t_num_regs
};
/*
* Client data (each client gets its own)
*/
struct max1619_data {
struct i2c_client *client;
struct mutex update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
/* registers values */
u8 temp[t_num_regs]; /* index with enum temp_index */
u8 alarms;
};
static const u8 regs_read[t_num_regs] = {
[t_input1] = MAX1619_REG_R_LOCAL_TEMP,
[t_input2] = MAX1619_REG_R_REMOTE_TEMP,
[t_low2] = MAX1619_REG_R_REMOTE_LOW,
[t_high2] = MAX1619_REG_R_REMOTE_HIGH,
[t_crit2] = MAX1619_REG_R_REMOTE_CRIT,
[t_hyst2] = MAX1619_REG_R_TCRIT_HYST,
};
static const u8 regs_write[t_num_regs] = {
[t_low2] = MAX1619_REG_W_REMOTE_LOW,
[t_high2] = MAX1619_REG_W_REMOTE_HIGH,
[t_crit2] = MAX1619_REG_W_REMOTE_CRIT,
[t_hyst2] = MAX1619_REG_W_TCRIT_HYST,
};
static struct max1619_data *max1619_update_device(struct device *dev)
{
struct max1619_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int config, i;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
dev_dbg(&client->dev, "Updating max1619 data.\n");
for (i = 0; i < t_num_regs; i++)
data->temp[i] = i2c_smbus_read_byte_data(client,
regs_read[i]);
data->alarms = i2c_smbus_read_byte_data(client,
MAX1619_REG_R_STATUS);
/* If OVERT polarity is low, reverse alarm bit */
config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
if (!(config & 0x20))
data->alarms ^= 0x02;
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->update_lock);
return data;
}
/*
* Sysfs stuff
*/
static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct max1619_data *data = max1619_update_device(dev);
return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
}
static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
const char *buf, size_t count)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct max1619_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
long val;
int err = kstrtol(buf, 10, &val);
if (err)
return err;
mutex_lock(&data->update_lock);
data->temp[attr->index] = temp_to_reg(val);
i2c_smbus_write_byte_data(client, regs_write[attr->index],
data->temp[attr->index]);
mutex_unlock(&data->update_lock);
return count;
}
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 ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
char *buf)
{
int bitnr = to_sensor_dev_attr(attr)->index;
struct max1619_data *data = max1619_update_device(dev);
return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, t_input1);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, t_input2);
static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp, set_temp,
t_low2);
static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, set_temp,
t_high2);
static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp, set_temp,
t_crit2);
static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp,
set_temp, t_hyst2);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
static struct attribute *max1619_attrs[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp2_min.dev_attr.attr,
&sensor_dev_attr_temp2_max.dev_attr.attr,
&sensor_dev_attr_temp2_crit.dev_attr.attr,
&sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
&dev_attr_alarms.attr,
&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_fault.dev_attr.attr,
&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(max1619);
/* Return 0 if detection is successful, -ENODEV otherwise */
static int max1619_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
u8 reg_config, reg_convrate, reg_status, man_id, chip_id;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
/* detection */
reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE);
reg_status = i2c_smbus_read_byte_data(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",
client->addr);
return -ENODEV;
}
/* identification */
man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID);
chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID);
if (man_id != 0x4D || chip_id != 0x04) {
dev_info(&adapter->dev,
"Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
man_id, chip_id);
return -ENODEV;
}
strlcpy(info->type, "max1619", I2C_NAME_SIZE);
return 0;
}
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_probe(struct i2c_client *new_client,
const struct i2c_device_id *id)
{
struct max1619_data *data;
struct device *hwmon_dev;
data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
data->client = new_client;
mutex_init(&data->update_lock);
/* Initialize the MAX1619 chip */
max1619_init_client(new_client);
hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
new_client->name,
data,
max1619_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id max1619_id[] = {
{ "max1619", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, max1619_id);
static struct i2c_driver max1619_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "max1619",
},
.probe = max1619_probe,
.id_table = max1619_id,
.detect = max1619_detect,
.address_list = normal_i2c,
};
module_i2c_driver(max1619_driver);
MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>");
MODULE_DESCRIPTION("MAX1619 sensor driver");
MODULE_LICENSE("GPL");