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 show_temp(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 set_temp(struct device *dev, struct device_attribute *devattr, 158 const char *buf, size_t count) 159 { 160 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 161 struct max1619_data *data = dev_get_drvdata(dev); 162 struct i2c_client *client = data->client; 163 long val; 164 int err = kstrtol(buf, 10, &val); 165 if (err) 166 return err; 167 168 mutex_lock(&data->update_lock); 169 data->temp[attr->index] = temp_to_reg(val); 170 i2c_smbus_write_byte_data(client, regs_write[attr->index], 171 data->temp[attr->index]); 172 mutex_unlock(&data->update_lock); 173 return count; 174 } 175 176 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr, 177 char *buf) 178 { 179 struct max1619_data *data = max1619_update_device(dev); 180 return sprintf(buf, "%d\n", data->alarms); 181 } 182 183 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr, 184 char *buf) 185 { 186 int bitnr = to_sensor_dev_attr(attr)->index; 187 struct max1619_data *data = max1619_update_device(dev); 188 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); 189 } 190 191 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, t_input1); 192 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, t_input2); 193 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 194 t_low2); 195 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 196 t_high2); 197 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp, set_temp, 198 t_crit2); 199 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp, 200 set_temp, t_hyst2); 201 202 static DEVICE_ATTR_RO(alarms); 203 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1); 204 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2); 205 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3); 206 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4); 207 208 static struct attribute *max1619_attrs[] = { 209 &sensor_dev_attr_temp1_input.dev_attr.attr, 210 &sensor_dev_attr_temp2_input.dev_attr.attr, 211 &sensor_dev_attr_temp2_min.dev_attr.attr, 212 &sensor_dev_attr_temp2_max.dev_attr.attr, 213 &sensor_dev_attr_temp2_crit.dev_attr.attr, 214 &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr, 215 216 &dev_attr_alarms.attr, 217 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 218 &sensor_dev_attr_temp2_fault.dev_attr.attr, 219 &sensor_dev_attr_temp2_min_alarm.dev_attr.attr, 220 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 221 NULL 222 }; 223 ATTRIBUTE_GROUPS(max1619); 224 225 /* Return 0 if detection is successful, -ENODEV otherwise */ 226 static int max1619_detect(struct i2c_client *client, 227 struct i2c_board_info *info) 228 { 229 struct i2c_adapter *adapter = client->adapter; 230 u8 reg_config, reg_convrate, reg_status, man_id, chip_id; 231 232 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 233 return -ENODEV; 234 235 /* detection */ 236 reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 237 reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE); 238 reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS); 239 if ((reg_config & 0x03) != 0x00 240 || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) { 241 dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n", 242 client->addr); 243 return -ENODEV; 244 } 245 246 /* identification */ 247 man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID); 248 chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID); 249 if (man_id != 0x4D || chip_id != 0x04) { 250 dev_info(&adapter->dev, 251 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n", 252 man_id, chip_id); 253 return -ENODEV; 254 } 255 256 strlcpy(info->type, "max1619", I2C_NAME_SIZE); 257 258 return 0; 259 } 260 261 static void max1619_init_client(struct i2c_client *client) 262 { 263 u8 config; 264 265 /* 266 * Start the conversions. 267 */ 268 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE, 269 5); /* 2 Hz */ 270 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG); 271 if (config & 0x40) 272 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG, 273 config & 0xBF); /* run */ 274 } 275 276 static int max1619_probe(struct i2c_client *new_client, 277 const struct i2c_device_id *id) 278 { 279 struct max1619_data *data; 280 struct device *hwmon_dev; 281 282 data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data), 283 GFP_KERNEL); 284 if (!data) 285 return -ENOMEM; 286 287 data->client = new_client; 288 mutex_init(&data->update_lock); 289 290 /* Initialize the MAX1619 chip */ 291 max1619_init_client(new_client); 292 293 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev, 294 new_client->name, 295 data, 296 max1619_groups); 297 return PTR_ERR_OR_ZERO(hwmon_dev); 298 } 299 300 static const struct i2c_device_id max1619_id[] = { 301 { "max1619", 0 }, 302 { } 303 }; 304 MODULE_DEVICE_TABLE(i2c, max1619_id); 305 306 static struct i2c_driver max1619_driver = { 307 .class = I2C_CLASS_HWMON, 308 .driver = { 309 .name = "max1619", 310 }, 311 .probe = max1619_probe, 312 .id_table = max1619_id, 313 .detect = max1619_detect, 314 .address_list = normal_i2c, 315 }; 316 317 module_i2c_driver(max1619_driver); 318 319 MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>"); 320 MODULE_DESCRIPTION("MAX1619 sensor driver"); 321 MODULE_LICENSE("GPL"); 322