1 /* 2 * max1619.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring 4 * Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net> 5 * Jean Delvare <jdelvare@suse.de> 6 * 7 * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim. 8 * It reports up to two temperatures (its own plus up to 9 * one external one). Complete datasheet can be 10 * obtained from Maxim's website at: 11 * http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or 16 * (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 */ 23 24 #include <linux/module.h> 25 #include <linux/init.h> 26 #include <linux/slab.h> 27 #include <linux/jiffies.h> 28 #include <linux/i2c.h> 29 #include <linux/hwmon.h> 30 #include <linux/hwmon-sysfs.h> 31 #include <linux/err.h> 32 #include <linux/mutex.h> 33 #include <linux/sysfs.h> 34 35 static const unsigned short normal_i2c[] = { 36 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; 37 38 /* 39 * The MAX1619 registers 40 */ 41 42 #define MAX1619_REG_R_MAN_ID 0xFE 43 #define MAX1619_REG_R_CHIP_ID 0xFF 44 #define MAX1619_REG_R_CONFIG 0x03 45 #define MAX1619_REG_W_CONFIG 0x09 46 #define MAX1619_REG_R_CONVRATE 0x04 47 #define MAX1619_REG_W_CONVRATE 0x0A 48 #define MAX1619_REG_R_STATUS 0x02 49 #define MAX1619_REG_R_LOCAL_TEMP 0x00 50 #define MAX1619_REG_R_REMOTE_TEMP 0x01 51 #define MAX1619_REG_R_REMOTE_HIGH 0x07 52 #define MAX1619_REG_W_REMOTE_HIGH 0x0D 53 #define MAX1619_REG_R_REMOTE_LOW 0x08 54 #define MAX1619_REG_W_REMOTE_LOW 0x0E 55 #define MAX1619_REG_R_REMOTE_CRIT 0x10 56 #define MAX1619_REG_W_REMOTE_CRIT 0x12 57 #define MAX1619_REG_R_TCRIT_HYST 0x11 58 #define MAX1619_REG_W_TCRIT_HYST 0x13 59 60 /* 61 * Conversions 62 */ 63 64 static int temp_from_reg(int val) 65 { 66 return (val & 0x80 ? val-0x100 : val) * 1000; 67 } 68 69 static int temp_to_reg(int val) 70 { 71 return (val < 0 ? val+0x100*1000 : val) / 1000; 72 } 73 74 enum temp_index { 75 t_input1 = 0, 76 t_input2, 77 t_low2, 78 t_high2, 79 t_crit2, 80 t_hyst2, 81 t_num_regs 82 }; 83 84 /* 85 * Client data (each client gets its own) 86 */ 87 88 struct max1619_data { 89 struct i2c_client *client; 90 struct mutex update_lock; 91 char valid; /* zero until following fields are valid */ 92 unsigned long last_updated; /* in jiffies */ 93 94 /* registers values */ 95 u8 temp[t_num_regs]; /* index with enum temp_index */ 96 u8 alarms; 97 }; 98 99 static const u8 regs_read[t_num_regs] = { 100 [t_input1] = MAX1619_REG_R_LOCAL_TEMP, 101 [t_input2] = MAX1619_REG_R_REMOTE_TEMP, 102 [t_low2] = MAX1619_REG_R_REMOTE_LOW, 103 [t_high2] = MAX1619_REG_R_REMOTE_HIGH, 104 [t_crit2] = MAX1619_REG_R_REMOTE_CRIT, 105 [t_hyst2] = MAX1619_REG_R_TCRIT_HYST, 106 }; 107 108 static const u8 regs_write[t_num_regs] = { 109 [t_low2] = MAX1619_REG_W_REMOTE_LOW, 110 [t_high2] = MAX1619_REG_W_REMOTE_HIGH, 111 [t_crit2] = MAX1619_REG_W_REMOTE_CRIT, 112 [t_hyst2] = MAX1619_REG_W_TCRIT_HYST, 113 }; 114 115 static struct max1619_data *max1619_update_device(struct device *dev) 116 { 117 struct max1619_data *data = dev_get_drvdata(dev); 118 struct i2c_client *client = data->client; 119 int config, i; 120 121 mutex_lock(&data->update_lock); 122 123 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) { 124 dev_dbg(&client->dev, "Updating max1619 data.\n"); 125 for (i = 0; i < t_num_regs; i++) 126 data->temp[i] = i2c_smbus_read_byte_data(client, 127 regs_read[i]); 128 data->alarms = i2c_smbus_read_byte_data(client, 129 MAX1619_REG_R_STATUS); 130 /* If OVERT polarity is low, reverse alarm bit */ 131 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 132 if (!(config & 0x20)) 133 data->alarms ^= 0x02; 134 135 data->last_updated = jiffies; 136 data->valid = 1; 137 } 138 139 mutex_unlock(&data->update_lock); 140 141 return data; 142 } 143 144 /* 145 * Sysfs stuff 146 */ 147 148 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr, 149 char *buf) 150 { 151 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 152 struct max1619_data *data = max1619_update_device(dev); 153 154 return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index])); 155 } 156 157 static ssize_t temp_store(struct device *dev, 158 struct device_attribute *devattr, const char *buf, 159 size_t count) 160 { 161 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 162 struct max1619_data *data = dev_get_drvdata(dev); 163 struct i2c_client *client = data->client; 164 long val; 165 int err = kstrtol(buf, 10, &val); 166 if (err) 167 return err; 168 169 mutex_lock(&data->update_lock); 170 data->temp[attr->index] = temp_to_reg(val); 171 i2c_smbus_write_byte_data(client, regs_write[attr->index], 172 data->temp[attr->index]); 173 mutex_unlock(&data->update_lock); 174 return count; 175 } 176 177 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr, 178 char *buf) 179 { 180 struct max1619_data *data = max1619_update_device(dev); 181 return sprintf(buf, "%d\n", data->alarms); 182 } 183 184 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr, 185 char *buf) 186 { 187 int bitnr = to_sensor_dev_attr(attr)->index; 188 struct max1619_data *data = max1619_update_device(dev); 189 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); 190 } 191 192 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, t_input1); 193 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, t_input2); 194 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp, t_low2); 195 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, t_high2); 196 static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp, t_crit2); 197 static SENSOR_DEVICE_ATTR_RW(temp2_crit_hyst, temp, t_hyst2); 198 199 static DEVICE_ATTR_RO(alarms); 200 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 1); 201 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 2); 202 static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, alarm, 3); 203 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 4); 204 205 static struct attribute *max1619_attrs[] = { 206 &sensor_dev_attr_temp1_input.dev_attr.attr, 207 &sensor_dev_attr_temp2_input.dev_attr.attr, 208 &sensor_dev_attr_temp2_min.dev_attr.attr, 209 &sensor_dev_attr_temp2_max.dev_attr.attr, 210 &sensor_dev_attr_temp2_crit.dev_attr.attr, 211 &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr, 212 213 &dev_attr_alarms.attr, 214 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 215 &sensor_dev_attr_temp2_fault.dev_attr.attr, 216 &sensor_dev_attr_temp2_min_alarm.dev_attr.attr, 217 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 218 NULL 219 }; 220 ATTRIBUTE_GROUPS(max1619); 221 222 /* Return 0 if detection is successful, -ENODEV otherwise */ 223 static int max1619_detect(struct i2c_client *client, 224 struct i2c_board_info *info) 225 { 226 struct i2c_adapter *adapter = client->adapter; 227 u8 reg_config, reg_convrate, reg_status, man_id, chip_id; 228 229 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 230 return -ENODEV; 231 232 /* detection */ 233 reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 234 reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE); 235 reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS); 236 if ((reg_config & 0x03) != 0x00 237 || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) { 238 dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n", 239 client->addr); 240 return -ENODEV; 241 } 242 243 /* identification */ 244 man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID); 245 chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID); 246 if (man_id != 0x4D || chip_id != 0x04) { 247 dev_info(&adapter->dev, 248 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n", 249 man_id, chip_id); 250 return -ENODEV; 251 } 252 253 strlcpy(info->type, "max1619", I2C_NAME_SIZE); 254 255 return 0; 256 } 257 258 static void max1619_init_client(struct i2c_client *client) 259 { 260 u8 config; 261 262 /* 263 * Start the conversions. 264 */ 265 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE, 266 5); /* 2 Hz */ 267 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 268 if (config & 0x40) 269 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG, 270 config & 0xBF); /* run */ 271 } 272 273 static int max1619_probe(struct i2c_client *new_client, 274 const struct i2c_device_id *id) 275 { 276 struct max1619_data *data; 277 struct device *hwmon_dev; 278 279 data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data), 280 GFP_KERNEL); 281 if (!data) 282 return -ENOMEM; 283 284 data->client = new_client; 285 mutex_init(&data->update_lock); 286 287 /* Initialize the MAX1619 chip */ 288 max1619_init_client(new_client); 289 290 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev, 291 new_client->name, 292 data, 293 max1619_groups); 294 return PTR_ERR_OR_ZERO(hwmon_dev); 295 } 296 297 static const struct i2c_device_id max1619_id[] = { 298 { "max1619", 0 }, 299 { } 300 }; 301 MODULE_DEVICE_TABLE(i2c, max1619_id); 302 303 #ifdef CONFIG_OF 304 static const struct of_device_id max1619_of_match[] = { 305 { .compatible = "maxim,max1619", }, 306 {}, 307 }; 308 309 MODULE_DEVICE_TABLE(of, max1619_of_match); 310 #endif 311 312 static struct i2c_driver max1619_driver = { 313 .class = I2C_CLASS_HWMON, 314 .driver = { 315 .name = "max1619", 316 .of_match_table = of_match_ptr(max1619_of_match), 317 }, 318 .probe = max1619_probe, 319 .id_table = max1619_id, 320 .detect = max1619_detect, 321 .address_list = normal_i2c, 322 }; 323 324 module_i2c_driver(max1619_driver); 325 326 MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>"); 327 MODULE_DESCRIPTION("MAX1619 sensor driver"); 328 MODULE_LICENSE("GPL"); 329