// 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; bool valid; /* false 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 = true; } 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; } strscpy(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");