1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * max1619.c - Part of lm_sensors, Linux kernel modules for hardware 4 * monitoring 5 * Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net> 6 * Jean Delvare <jdelvare@suse.de> 7 * 8 * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim. 9 * It reports up to two temperatures (its own plus up to 10 * one external one). Complete datasheet can be 11 * obtained from Maxim's website at: 12 * http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf 13 */ 14 15 #include <linux/module.h> 16 #include <linux/init.h> 17 #include <linux/slab.h> 18 #include <linux/jiffies.h> 19 #include <linux/i2c.h> 20 #include <linux/hwmon.h> 21 #include <linux/hwmon-sysfs.h> 22 #include <linux/err.h> 23 #include <linux/mutex.h> 24 #include <linux/sysfs.h> 25 26 static const unsigned short normal_i2c[] = { 27 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; 28 29 /* 30 * The MAX1619 registers 31 */ 32 33 #define MAX1619_REG_R_MAN_ID 0xFE 34 #define MAX1619_REG_R_CHIP_ID 0xFF 35 #define MAX1619_REG_R_CONFIG 0x03 36 #define MAX1619_REG_W_CONFIG 0x09 37 #define MAX1619_REG_R_CONVRATE 0x04 38 #define MAX1619_REG_W_CONVRATE 0x0A 39 #define MAX1619_REG_R_STATUS 0x02 40 #define MAX1619_REG_R_LOCAL_TEMP 0x00 41 #define MAX1619_REG_R_REMOTE_TEMP 0x01 42 #define MAX1619_REG_R_REMOTE_HIGH 0x07 43 #define MAX1619_REG_W_REMOTE_HIGH 0x0D 44 #define MAX1619_REG_R_REMOTE_LOW 0x08 45 #define MAX1619_REG_W_REMOTE_LOW 0x0E 46 #define MAX1619_REG_R_REMOTE_CRIT 0x10 47 #define MAX1619_REG_W_REMOTE_CRIT 0x12 48 #define MAX1619_REG_R_TCRIT_HYST 0x11 49 #define MAX1619_REG_W_TCRIT_HYST 0x13 50 51 /* 52 * Conversions 53 */ 54 55 static int temp_from_reg(int val) 56 { 57 return (val & 0x80 ? val-0x100 : val) * 1000; 58 } 59 60 static int temp_to_reg(int val) 61 { 62 return (val < 0 ? val+0x100*1000 : val) / 1000; 63 } 64 65 enum temp_index { 66 t_input1 = 0, 67 t_input2, 68 t_low2, 69 t_high2, 70 t_crit2, 71 t_hyst2, 72 t_num_regs 73 }; 74 75 /* 76 * Client data (each client gets its own) 77 */ 78 79 struct max1619_data { 80 struct i2c_client *client; 81 struct mutex update_lock; 82 bool valid; /* false until following fields are valid */ 83 unsigned long last_updated; /* in jiffies */ 84 85 /* registers values */ 86 u8 temp[t_num_regs]; /* index with enum temp_index */ 87 u8 alarms; 88 }; 89 90 static const u8 regs_read[t_num_regs] = { 91 [t_input1] = MAX1619_REG_R_LOCAL_TEMP, 92 [t_input2] = MAX1619_REG_R_REMOTE_TEMP, 93 [t_low2] = MAX1619_REG_R_REMOTE_LOW, 94 [t_high2] = MAX1619_REG_R_REMOTE_HIGH, 95 [t_crit2] = MAX1619_REG_R_REMOTE_CRIT, 96 [t_hyst2] = MAX1619_REG_R_TCRIT_HYST, 97 }; 98 99 static const u8 regs_write[t_num_regs] = { 100 [t_low2] = MAX1619_REG_W_REMOTE_LOW, 101 [t_high2] = MAX1619_REG_W_REMOTE_HIGH, 102 [t_crit2] = MAX1619_REG_W_REMOTE_CRIT, 103 [t_hyst2] = MAX1619_REG_W_TCRIT_HYST, 104 }; 105 106 static struct max1619_data *max1619_update_device(struct device *dev) 107 { 108 struct max1619_data *data = dev_get_drvdata(dev); 109 struct i2c_client *client = data->client; 110 int config, i; 111 112 mutex_lock(&data->update_lock); 113 114 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 115 dev_dbg(&client->dev, "Updating max1619 data.\n"); 116 for (i = 0; i < t_num_regs; i++) 117 data->temp[i] = i2c_smbus_read_byte_data(client, 118 regs_read[i]); 119 data->alarms = i2c_smbus_read_byte_data(client, 120 MAX1619_REG_R_STATUS); 121 /* If OVERT polarity is low, reverse alarm bit */ 122 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 123 if (!(config & 0x20)) 124 data->alarms ^= 0x02; 125 126 data->last_updated = jiffies; 127 data->valid = true; 128 } 129 130 mutex_unlock(&data->update_lock); 131 132 return data; 133 } 134 135 /* 136 * Sysfs stuff 137 */ 138 139 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr, 140 char *buf) 141 { 142 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 143 struct max1619_data *data = max1619_update_device(dev); 144 145 return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index])); 146 } 147 148 static ssize_t temp_store(struct device *dev, 149 struct device_attribute *devattr, const char *buf, 150 size_t count) 151 { 152 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 153 struct max1619_data *data = dev_get_drvdata(dev); 154 struct i2c_client *client = data->client; 155 long val; 156 int err = kstrtol(buf, 10, &val); 157 if (err) 158 return err; 159 160 mutex_lock(&data->update_lock); 161 data->temp[attr->index] = temp_to_reg(val); 162 i2c_smbus_write_byte_data(client, regs_write[attr->index], 163 data->temp[attr->index]); 164 mutex_unlock(&data->update_lock); 165 return count; 166 } 167 168 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr, 169 char *buf) 170 { 171 struct max1619_data *data = max1619_update_device(dev); 172 return sprintf(buf, "%d\n", data->alarms); 173 } 174 175 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr, 176 char *buf) 177 { 178 int bitnr = to_sensor_dev_attr(attr)->index; 179 struct max1619_data *data = max1619_update_device(dev); 180 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); 181 } 182 183 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, t_input1); 184 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, t_input2); 185 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp, t_low2); 186 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, t_high2); 187 static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp, t_crit2); 188 static SENSOR_DEVICE_ATTR_RW(temp2_crit_hyst, temp, t_hyst2); 189 190 static DEVICE_ATTR_RO(alarms); 191 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 1); 192 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 2); 193 static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, alarm, 3); 194 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 4); 195 196 static struct attribute *max1619_attrs[] = { 197 &sensor_dev_attr_temp1_input.dev_attr.attr, 198 &sensor_dev_attr_temp2_input.dev_attr.attr, 199 &sensor_dev_attr_temp2_min.dev_attr.attr, 200 &sensor_dev_attr_temp2_max.dev_attr.attr, 201 &sensor_dev_attr_temp2_crit.dev_attr.attr, 202 &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr, 203 204 &dev_attr_alarms.attr, 205 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 206 &sensor_dev_attr_temp2_fault.dev_attr.attr, 207 &sensor_dev_attr_temp2_min_alarm.dev_attr.attr, 208 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 209 NULL 210 }; 211 ATTRIBUTE_GROUPS(max1619); 212 213 /* Return 0 if detection is successful, -ENODEV otherwise */ 214 static int max1619_detect(struct i2c_client *client, 215 struct i2c_board_info *info) 216 { 217 struct i2c_adapter *adapter = client->adapter; 218 u8 reg_config, reg_convrate, reg_status, man_id, chip_id; 219 220 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 221 return -ENODEV; 222 223 /* detection */ 224 reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 225 reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE); 226 reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS); 227 if ((reg_config & 0x03) != 0x00 228 || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) { 229 dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n", 230 client->addr); 231 return -ENODEV; 232 } 233 234 /* identification */ 235 man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID); 236 chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID); 237 if (man_id != 0x4D || chip_id != 0x04) { 238 dev_info(&adapter->dev, 239 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n", 240 man_id, chip_id); 241 return -ENODEV; 242 } 243 244 strscpy(info->type, "max1619", I2C_NAME_SIZE); 245 246 return 0; 247 } 248 249 static void max1619_init_client(struct i2c_client *client) 250 { 251 u8 config; 252 253 /* 254 * Start the conversions. 255 */ 256 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE, 257 5); /* 2 Hz */ 258 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 259 if (config & 0x40) 260 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG, 261 config & 0xBF); /* run */ 262 } 263 264 static int max1619_probe(struct i2c_client *new_client) 265 { 266 struct max1619_data *data; 267 struct device *hwmon_dev; 268 269 data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data), 270 GFP_KERNEL); 271 if (!data) 272 return -ENOMEM; 273 274 data->client = new_client; 275 mutex_init(&data->update_lock); 276 277 /* Initialize the MAX1619 chip */ 278 max1619_init_client(new_client); 279 280 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev, 281 new_client->name, 282 data, 283 max1619_groups); 284 return PTR_ERR_OR_ZERO(hwmon_dev); 285 } 286 287 static const struct i2c_device_id max1619_id[] = { 288 { "max1619", 0 }, 289 { } 290 }; 291 MODULE_DEVICE_TABLE(i2c, max1619_id); 292 293 #ifdef CONFIG_OF 294 static const struct of_device_id max1619_of_match[] = { 295 { .compatible = "maxim,max1619", }, 296 {}, 297 }; 298 299 MODULE_DEVICE_TABLE(of, max1619_of_match); 300 #endif 301 302 static struct i2c_driver max1619_driver = { 303 .class = I2C_CLASS_HWMON, 304 .driver = { 305 .name = "max1619", 306 .of_match_table = of_match_ptr(max1619_of_match), 307 }, 308 .probe = max1619_probe, 309 .id_table = max1619_id, 310 .detect = max1619_detect, 311 .address_list = normal_i2c, 312 }; 313 314 module_i2c_driver(max1619_driver); 315 316 MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>"); 317 MODULE_DESCRIPTION("MAX1619 sensor driver"); 318 MODULE_LICENSE("GPL"); 319