diff options
Diffstat (limited to 'drivers/hwmon/max1619.c')
| -rw-r--r-- | drivers/hwmon/max1619.c | 318 |
1 files changed, 318 insertions, 0 deletions
diff --git a/drivers/hwmon/max1619.c b/drivers/hwmon/max1619.c new file mode 100644 index 000000000..8bd941cae --- /dev/null +++ b/drivers/hwmon/max1619.c @@ -0,0 +1,318 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * 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 + */ + +#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 temp_show(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 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 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 alarm_show(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_RO(temp1_input, temp, t_input1); +static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, t_input2); +static SENSOR_DEVICE_ATTR_RW(temp2_min, temp, t_low2); +static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, t_high2); +static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp, t_crit2); +static SENSOR_DEVICE_ATTR_RW(temp2_crit_hyst, temp, t_hyst2); + +static DEVICE_ATTR_RO(alarms); +static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 1); +static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 2); +static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, alarm, 3); +static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 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) +{ + 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); + +#ifdef CONFIG_OF +static const struct of_device_id max1619_of_match[] = { + { .compatible = "maxim,max1619", }, + {}, +}; + +MODULE_DEVICE_TABLE(of, max1619_of_match); +#endif + +static struct i2c_driver max1619_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "max1619", + .of_match_table = of_match_ptr(max1619_of_match), + }, + .probe_new = 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"); |