forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
343 lines
9.4 KiB
343 lines
9.4 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* lm92 - Hardware monitoring driver |
|
* Copyright (C) 2005-2008 Jean Delvare <[email protected]> |
|
* |
|
* Based on the lm90 driver, with some ideas taken from the lm_sensors |
|
* lm92 driver as well. |
|
* |
|
* The LM92 is a sensor chip made by National Semiconductor. It reports |
|
* its own temperature with a 0.0625 deg resolution and a 0.33 deg |
|
* accuracy. Complete datasheet can be obtained from National's website |
|
* at: |
|
* http://www.national.com/pf/LM/LM92.html |
|
* |
|
* This driver also supports the MAX6635 sensor chip made by Maxim. |
|
* This chip is compatible with the LM92, but has a lesser accuracy |
|
* (1.0 deg). Complete datasheet can be obtained from Maxim's website |
|
* at: |
|
* http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074 |
|
* |
|
* Since the LM92 was the first chipset supported by this driver, most |
|
* comments will refer to this chipset, but are actually general and |
|
* concern all supported chipsets, unless mentioned otherwise. |
|
* |
|
* Support could easily be added for the National Semiconductor LM76 |
|
* and Maxim MAX6633 and MAX6634 chips, which are mostly compatible |
|
* with the LM92. |
|
*/ |
|
|
|
#include <linux/module.h> |
|
#include <linux/init.h> |
|
#include <linux/slab.h> |
|
#include <linux/i2c.h> |
|
#include <linux/hwmon.h> |
|
#include <linux/hwmon-sysfs.h> |
|
#include <linux/err.h> |
|
#include <linux/mutex.h> |
|
#include <linux/jiffies.h> |
|
|
|
/* |
|
* The LM92 and MAX6635 have 2 two-state pins for address selection, |
|
* resulting in 4 possible addresses. |
|
*/ |
|
static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, |
|
I2C_CLIENT_END }; |
|
enum chips { lm92, max6635 }; |
|
|
|
/* The LM92 registers */ |
|
#define LM92_REG_CONFIG 0x01 /* 8-bit, RW */ |
|
#define LM92_REG_TEMP 0x00 /* 16-bit, RO */ |
|
#define LM92_REG_TEMP_HYST 0x02 /* 16-bit, RW */ |
|
#define LM92_REG_TEMP_CRIT 0x03 /* 16-bit, RW */ |
|
#define LM92_REG_TEMP_LOW 0x04 /* 16-bit, RW */ |
|
#define LM92_REG_TEMP_HIGH 0x05 /* 16-bit, RW */ |
|
#define LM92_REG_MAN_ID 0x07 /* 16-bit, RO, LM92 only */ |
|
|
|
/* |
|
* The LM92 uses signed 13-bit values with LSB = 0.0625 degree Celsius, |
|
* left-justified in 16-bit registers. No rounding is done, with such |
|
* a resolution it's just not worth it. Note that the MAX6635 doesn't |
|
* make use of the 4 lower bits for limits (i.e. effective resolution |
|
* for limits is 1 degree Celsius). |
|
*/ |
|
static inline int TEMP_FROM_REG(s16 reg) |
|
{ |
|
return reg / 8 * 625 / 10; |
|
} |
|
|
|
static inline s16 TEMP_TO_REG(long val) |
|
{ |
|
val = clamp_val(val, -60000, 160000); |
|
return val * 10 / 625 * 8; |
|
} |
|
|
|
/* Alarm flags are stored in the 3 LSB of the temperature register */ |
|
static inline u8 ALARMS_FROM_REG(s16 reg) |
|
{ |
|
return reg & 0x0007; |
|
} |
|
|
|
enum temp_index { |
|
t_input, |
|
t_crit, |
|
t_min, |
|
t_max, |
|
t_hyst, |
|
t_num_regs |
|
}; |
|
|
|
static const u8 regs[t_num_regs] = { |
|
[t_input] = LM92_REG_TEMP, |
|
[t_crit] = LM92_REG_TEMP_CRIT, |
|
[t_min] = LM92_REG_TEMP_LOW, |
|
[t_max] = LM92_REG_TEMP_HIGH, |
|
[t_hyst] = LM92_REG_TEMP_HYST, |
|
}; |
|
|
|
/* Client data (each client gets its own) */ |
|
struct lm92_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 */ |
|
s16 temp[t_num_regs]; /* index with enum temp_index */ |
|
}; |
|
|
|
/* |
|
* Sysfs attributes and callback functions |
|
*/ |
|
|
|
static struct lm92_data *lm92_update_device(struct device *dev) |
|
{ |
|
struct lm92_data *data = dev_get_drvdata(dev); |
|
struct i2c_client *client = data->client; |
|
int i; |
|
|
|
mutex_lock(&data->update_lock); |
|
|
|
if (time_after(jiffies, data->last_updated + HZ) || |
|
!data->valid) { |
|
dev_dbg(&client->dev, "Updating lm92 data\n"); |
|
for (i = 0; i < t_num_regs; i++) { |
|
data->temp[i] = |
|
i2c_smbus_read_word_swapped(client, regs[i]); |
|
} |
|
data->last_updated = jiffies; |
|
data->valid = 1; |
|
} |
|
|
|
mutex_unlock(&data->update_lock); |
|
|
|
return data; |
|
} |
|
|
|
static ssize_t temp_show(struct device *dev, struct device_attribute *devattr, |
|
char *buf) |
|
{ |
|
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); |
|
struct lm92_data *data = lm92_update_device(dev); |
|
|
|
return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index])); |
|
} |
|
|
|
static ssize_t temp_store(struct device *dev, |
|
struct device_attribute *devattr, const char *buf, |
|
size_t count) |
|
{ |
|
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); |
|
struct lm92_data *data = dev_get_drvdata(dev); |
|
struct i2c_client *client = data->client; |
|
int nr = attr->index; |
|
long val; |
|
int err; |
|
|
|
err = kstrtol(buf, 10, &val); |
|
if (err) |
|
return err; |
|
|
|
mutex_lock(&data->update_lock); |
|
data->temp[nr] = TEMP_TO_REG(val); |
|
i2c_smbus_write_word_swapped(client, regs[nr], data->temp[nr]); |
|
mutex_unlock(&data->update_lock); |
|
return count; |
|
} |
|
|
|
static ssize_t temp_hyst_show(struct device *dev, |
|
struct device_attribute *devattr, char *buf) |
|
{ |
|
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); |
|
struct lm92_data *data = lm92_update_device(dev); |
|
|
|
return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]) |
|
- TEMP_FROM_REG(data->temp[t_hyst])); |
|
} |
|
|
|
static ssize_t temp1_min_hyst_show(struct device *dev, |
|
struct device_attribute *attr, char *buf) |
|
{ |
|
struct lm92_data *data = lm92_update_device(dev); |
|
|
|
return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[t_min]) |
|
+ TEMP_FROM_REG(data->temp[t_hyst])); |
|
} |
|
|
|
static ssize_t temp_hyst_store(struct device *dev, |
|
struct device_attribute *devattr, |
|
const char *buf, size_t count) |
|
{ |
|
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); |
|
struct lm92_data *data = dev_get_drvdata(dev); |
|
struct i2c_client *client = data->client; |
|
long val; |
|
int err; |
|
|
|
err = kstrtol(buf, 10, &val); |
|
if (err) |
|
return err; |
|
|
|
val = clamp_val(val, -120000, 220000); |
|
mutex_lock(&data->update_lock); |
|
data->temp[t_hyst] = |
|
TEMP_TO_REG(TEMP_FROM_REG(data->temp[attr->index]) - val); |
|
i2c_smbus_write_word_swapped(client, LM92_REG_TEMP_HYST, |
|
data->temp[t_hyst]); |
|
mutex_unlock(&data->update_lock); |
|
return count; |
|
} |
|
|
|
static ssize_t alarms_show(struct device *dev, struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
struct lm92_data *data = lm92_update_device(dev); |
|
|
|
return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->temp[t_input])); |
|
} |
|
|
|
static ssize_t alarm_show(struct device *dev, struct device_attribute *attr, |
|
char *buf) |
|
{ |
|
int bitnr = to_sensor_dev_attr(attr)->index; |
|
struct lm92_data *data = lm92_update_device(dev); |
|
return sprintf(buf, "%d\n", (data->temp[t_input] >> bitnr) & 1); |
|
} |
|
|
|
static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, t_input); |
|
static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp, t_crit); |
|
static SENSOR_DEVICE_ATTR_RW(temp1_crit_hyst, temp_hyst, t_crit); |
|
static SENSOR_DEVICE_ATTR_RW(temp1_min, temp, t_min); |
|
static DEVICE_ATTR_RO(temp1_min_hyst); |
|
static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, t_max); |
|
static SENSOR_DEVICE_ATTR_RO(temp1_max_hyst, temp_hyst, t_max); |
|
static DEVICE_ATTR_RO(alarms); |
|
static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 2); |
|
static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, alarm, 0); |
|
static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 1); |
|
|
|
/* |
|
* Detection and registration |
|
*/ |
|
|
|
static void lm92_init_client(struct i2c_client *client) |
|
{ |
|
u8 config; |
|
|
|
/* Start the conversions if needed */ |
|
config = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG); |
|
if (config & 0x01) |
|
i2c_smbus_write_byte_data(client, LM92_REG_CONFIG, |
|
config & 0xFE); |
|
} |
|
|
|
static struct attribute *lm92_attrs[] = { |
|
&sensor_dev_attr_temp1_input.dev_attr.attr, |
|
&sensor_dev_attr_temp1_crit.dev_attr.attr, |
|
&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, |
|
&sensor_dev_attr_temp1_min.dev_attr.attr, |
|
&dev_attr_temp1_min_hyst.attr, |
|
&sensor_dev_attr_temp1_max.dev_attr.attr, |
|
&sensor_dev_attr_temp1_max_hyst.dev_attr.attr, |
|
&dev_attr_alarms.attr, |
|
&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, |
|
&sensor_dev_attr_temp1_min_alarm.dev_attr.attr, |
|
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr, |
|
NULL |
|
}; |
|
ATTRIBUTE_GROUPS(lm92); |
|
|
|
/* Return 0 if detection is successful, -ENODEV otherwise */ |
|
static int lm92_detect(struct i2c_client *new_client, |
|
struct i2c_board_info *info) |
|
{ |
|
struct i2c_adapter *adapter = new_client->adapter; |
|
u8 config; |
|
u16 man_id; |
|
|
|
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
|
| I2C_FUNC_SMBUS_WORD_DATA)) |
|
return -ENODEV; |
|
|
|
config = i2c_smbus_read_byte_data(new_client, LM92_REG_CONFIG); |
|
man_id = i2c_smbus_read_word_data(new_client, LM92_REG_MAN_ID); |
|
|
|
if ((config & 0xe0) == 0x00 && man_id == 0x0180) |
|
pr_info("lm92: Found National Semiconductor LM92 chip\n"); |
|
else |
|
return -ENODEV; |
|
|
|
strlcpy(info->type, "lm92", I2C_NAME_SIZE); |
|
|
|
return 0; |
|
} |
|
|
|
static int lm92_probe(struct i2c_client *new_client) |
|
{ |
|
struct device *hwmon_dev; |
|
struct lm92_data *data; |
|
|
|
data = devm_kzalloc(&new_client->dev, sizeof(struct lm92_data), |
|
GFP_KERNEL); |
|
if (!data) |
|
return -ENOMEM; |
|
|
|
data->client = new_client; |
|
mutex_init(&data->update_lock); |
|
|
|
/* Initialize the chipset */ |
|
lm92_init_client(new_client); |
|
|
|
hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev, |
|
new_client->name, |
|
data, lm92_groups); |
|
return PTR_ERR_OR_ZERO(hwmon_dev); |
|
} |
|
|
|
/* |
|
* Module and driver stuff |
|
*/ |
|
|
|
static const struct i2c_device_id lm92_id[] = { |
|
{ "lm92", lm92 }, |
|
{ "max6635", max6635 }, |
|
{ } |
|
}; |
|
MODULE_DEVICE_TABLE(i2c, lm92_id); |
|
|
|
static struct i2c_driver lm92_driver = { |
|
.class = I2C_CLASS_HWMON, |
|
.driver = { |
|
.name = "lm92", |
|
}, |
|
.probe_new = lm92_probe, |
|
.id_table = lm92_id, |
|
.detect = lm92_detect, |
|
.address_list = normal_i2c, |
|
}; |
|
|
|
module_i2c_driver(lm92_driver); |
|
|
|
MODULE_AUTHOR("Jean Delvare <[email protected]>"); |
|
MODULE_DESCRIPTION("LM92/MAX6635 driver"); |
|
MODULE_LICENSE("GPL");
|
|
|