linux/drivers/hwmon/max1619.c
Julia Lawall 23eb359dd6 hwmon: (max1619) use permission-specific DEVICE_ATTR variants
Use DEVICE_ATTR_RO for read-only attributes. This simplifies the source
code, improves readbility, and reduces the chance of inconsistencies.

The conversion was done automatically using coccinelle. It was validated
by compiling both the old and the new source code and comparing its text,
data, and bss size.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
[groeck: Updated description]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-01-02 10:19:45 -08:00

322 lines
9.2 KiB
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 alarms_show(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_RO(alarms);
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");