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/err.h> 16 #include <linux/hwmon.h> 17 #include <linux/i2c.h> 18 #include <linux/init.h> 19 #include <linux/module.h> 20 #include <linux/regmap.h> 21 #include <linux/util_macros.h> 22 23 static const unsigned short normal_i2c[] = { 24 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END }; 25 26 #define MAX1619_REG_LOCAL_TEMP 0x00 27 #define MAX1619_REG_REMOTE_TEMP 0x01 28 #define MAX1619_REG_STATUS 0x02 29 #define MAX1619_REG_CONFIG 0x03 30 #define MAX1619_REG_CONVRATE 0x04 31 #define MAX1619_REG_REMOTE_HIGH 0x07 32 #define MAX1619_REG_REMOTE_LOW 0x08 33 #define MAX1619_REG_REMOTE_CRIT 0x10 34 #define MAX1619_REG_REMOTE_CRIT_HYST 0x11 35 #define MAX1619_REG_MAN_ID 0xFE 36 #define MAX1619_REG_CHIP_ID 0xFF 37 38 static int get_alarms(struct regmap *regmap) 39 { 40 static u32 regs[2] = { MAX1619_REG_STATUS, MAX1619_REG_CONFIG }; 41 u8 regdata[2]; 42 int ret; 43 44 ret = regmap_multi_reg_read(regmap, regs, regdata, 2); 45 if (ret) 46 return ret; 47 48 /* OVERT status bit may be reversed */ 49 if (!(regdata[1] & 0x20)) 50 regdata[0] ^= 0x02; 51 52 return regdata[0] & 0x1e; 53 } 54 55 static int max1619_temp_read(struct regmap *regmap, u32 attr, int channel, long *val) 56 { 57 int reg = -1, alarm_bit = 0; 58 u32 temp; 59 int ret; 60 61 switch (attr) { 62 case hwmon_temp_input: 63 reg = channel ? MAX1619_REG_REMOTE_TEMP : MAX1619_REG_LOCAL_TEMP; 64 break; 65 case hwmon_temp_min: 66 reg = MAX1619_REG_REMOTE_LOW; 67 break; 68 case hwmon_temp_max: 69 reg = MAX1619_REG_REMOTE_HIGH; 70 break; 71 case hwmon_temp_crit: 72 reg = MAX1619_REG_REMOTE_CRIT; 73 break; 74 case hwmon_temp_crit_hyst: 75 reg = MAX1619_REG_REMOTE_CRIT_HYST; 76 break; 77 case hwmon_temp_min_alarm: 78 alarm_bit = 3; 79 break; 80 case hwmon_temp_max_alarm: 81 alarm_bit = 4; 82 break; 83 case hwmon_temp_crit_alarm: 84 alarm_bit = 1; 85 break; 86 case hwmon_temp_fault: 87 alarm_bit = 2; 88 break; 89 default: 90 return -EOPNOTSUPP; 91 } 92 if (reg >= 0) { 93 ret = regmap_read(regmap, reg, &temp); 94 if (ret < 0) 95 return ret; 96 *val = sign_extend32(temp, 7) * 1000; 97 } else { 98 ret = get_alarms(regmap); 99 if (ret < 0) 100 return ret; 101 *val = !!(ret & BIT(alarm_bit)); 102 } 103 return 0; 104 } 105 106 static u16 update_intervals[] = { 16000, 8000, 4000, 2000, 1000, 500, 250, 125 }; 107 108 static int max1619_chip_read(struct regmap *regmap, u32 attr, long *val) 109 { 110 int alarms, ret; 111 u32 regval; 112 113 switch (attr) { 114 case hwmon_chip_update_interval: 115 ret = regmap_read(regmap, MAX1619_REG_CONVRATE, ®val); 116 if (ret < 0) 117 return ret; 118 *val = update_intervals[regval & 7]; 119 break; 120 case hwmon_chip_alarms: 121 alarms = get_alarms(regmap); 122 if (alarms < 0) 123 return alarms; 124 *val = alarms; 125 break; 126 default: 127 return -EOPNOTSUPP; 128 } 129 return 0; 130 } 131 132 static int max1619_read(struct device *dev, enum hwmon_sensor_types type, 133 u32 attr, int channel, long *val) 134 { 135 struct regmap *regmap = dev_get_drvdata(dev); 136 137 switch (type) { 138 case hwmon_chip: 139 return max1619_chip_read(regmap, attr, val); 140 case hwmon_temp: 141 return max1619_temp_read(regmap, attr, channel, val); 142 default: 143 return -EOPNOTSUPP; 144 } 145 } 146 147 static int max1619_chip_write(struct regmap *regmap, u32 attr, long val) 148 { 149 switch (attr) { 150 case hwmon_chip_update_interval: 151 val = find_closest_descending(val, update_intervals, ARRAY_SIZE(update_intervals)); 152 return regmap_write(regmap, MAX1619_REG_CONVRATE, val); 153 default: 154 return -EOPNOTSUPP; 155 } 156 } 157 158 static int max1619_temp_write(struct regmap *regmap, 159 u32 attr, int channel, long val) 160 { 161 int reg; 162 163 switch (attr) { 164 case hwmon_temp_min: 165 reg = MAX1619_REG_REMOTE_LOW; 166 break; 167 case hwmon_temp_max: 168 reg = MAX1619_REG_REMOTE_HIGH; 169 break; 170 case hwmon_temp_crit: 171 reg = MAX1619_REG_REMOTE_CRIT; 172 break; 173 case hwmon_temp_crit_hyst: 174 reg = MAX1619_REG_REMOTE_CRIT_HYST; 175 break; 176 default: 177 return -EOPNOTSUPP; 178 } 179 val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000); 180 return regmap_write(regmap, reg, val); 181 } 182 183 static int max1619_write(struct device *dev, enum hwmon_sensor_types type, 184 u32 attr, int channel, long val) 185 { 186 struct regmap *regmap = dev_get_drvdata(dev); 187 188 switch (type) { 189 case hwmon_chip: 190 return max1619_chip_write(regmap, attr, val); 191 case hwmon_temp: 192 return max1619_temp_write(regmap, attr, channel, val); 193 default: 194 return -EOPNOTSUPP; 195 } 196 } 197 198 static umode_t max1619_is_visible(const void *_data, enum hwmon_sensor_types type, 199 u32 attr, int channel) 200 { 201 switch (type) { 202 case hwmon_chip: 203 switch (attr) { 204 case hwmon_chip_update_interval: 205 return 0644; 206 case hwmon_chip_alarms: 207 return 0444; 208 default: 209 break; 210 } 211 break; 212 case hwmon_temp: 213 switch (attr) { 214 case hwmon_temp_input: 215 return 0444; 216 case hwmon_temp_min: 217 case hwmon_temp_max: 218 case hwmon_temp_crit: 219 case hwmon_temp_crit_hyst: 220 return 0644; 221 case hwmon_temp_min_alarm: 222 case hwmon_temp_max_alarm: 223 case hwmon_temp_crit_alarm: 224 case hwmon_temp_fault: 225 return 0444; 226 default: 227 break; 228 } 229 break; 230 default: 231 break; 232 } 233 return 0; 234 } 235 236 static const struct hwmon_channel_info * const max1619_info[] = { 237 HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS | HWMON_C_UPDATE_INTERVAL), 238 HWMON_CHANNEL_INFO(temp, 239 HWMON_T_INPUT, 240 HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX | 241 HWMON_T_CRIT | HWMON_T_CRIT_HYST | 242 HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM | 243 HWMON_T_CRIT_ALARM | HWMON_T_FAULT), 244 NULL 245 }; 246 247 static const struct hwmon_ops max1619_hwmon_ops = { 248 .is_visible = max1619_is_visible, 249 .read = max1619_read, 250 .write = max1619_write, 251 }; 252 253 static const struct hwmon_chip_info max1619_chip_info = { 254 .ops = &max1619_hwmon_ops, 255 .info = max1619_info, 256 }; 257 258 /* Return 0 if detection is successful, -ENODEV otherwise */ 259 static int max1619_detect(struct i2c_client *client, 260 struct i2c_board_info *info) 261 { 262 struct i2c_adapter *adapter = client->adapter; 263 int regval; 264 265 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 266 return -ENODEV; 267 268 regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CONFIG); 269 if (regval < 0 || (regval & 0x03)) 270 return -ENODEV; 271 regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CONVRATE); 272 if (regval < 0 || regval > 0x07) 273 return -ENODEV; 274 regval = i2c_smbus_read_byte_data(client, MAX1619_REG_STATUS); 275 if (regval < 0 || (regval & 0x61)) 276 return -ENODEV; 277 278 regval = i2c_smbus_read_byte_data(client, MAX1619_REG_MAN_ID); 279 if (regval != 0x4d) 280 return -ENODEV; 281 regval = i2c_smbus_read_byte_data(client, MAX1619_REG_CHIP_ID); 282 if (regval != 0x04) 283 return -ENODEV; 284 285 strscpy(info->type, "max1619", I2C_NAME_SIZE); 286 287 return 0; 288 } 289 290 static int max1619_init_chip(struct regmap *regmap) 291 { 292 int ret; 293 294 ret = regmap_write(regmap, MAX1619_REG_CONVRATE, 5); /* 2 Hz */ 295 if (ret) 296 return ret; 297 298 /* Start conversions */ 299 return regmap_clear_bits(regmap, MAX1619_REG_CONFIG, 0x40); 300 } 301 302 /* regmap */ 303 304 static int max1619_reg_read(void *context, unsigned int reg, unsigned int *val) 305 { 306 int ret; 307 308 ret = i2c_smbus_read_byte_data(context, reg); 309 if (ret < 0) 310 return ret; 311 312 *val = ret; 313 return 0; 314 } 315 316 static int max1619_reg_write(void *context, unsigned int reg, unsigned int val) 317 { 318 int offset = reg < MAX1619_REG_REMOTE_CRIT ? 6 : 2; 319 320 return i2c_smbus_write_byte_data(context, reg + offset, val); 321 } 322 323 static bool max1619_regmap_is_volatile(struct device *dev, unsigned int reg) 324 { 325 return reg <= MAX1619_REG_STATUS; 326 } 327 328 static bool max1619_regmap_is_writeable(struct device *dev, unsigned int reg) 329 { 330 return reg > MAX1619_REG_STATUS && reg <= MAX1619_REG_REMOTE_CRIT_HYST; 331 } 332 333 static const struct regmap_config max1619_regmap_config = { 334 .reg_bits = 8, 335 .val_bits = 8, 336 .max_register = MAX1619_REG_REMOTE_CRIT_HYST, 337 .cache_type = REGCACHE_MAPLE, 338 .volatile_reg = max1619_regmap_is_volatile, 339 .writeable_reg = max1619_regmap_is_writeable, 340 }; 341 342 static const struct regmap_bus max1619_regmap_bus = { 343 .reg_write = max1619_reg_write, 344 .reg_read = max1619_reg_read, 345 }; 346 347 static int max1619_probe(struct i2c_client *client) 348 { 349 struct device *dev = &client->dev; 350 struct device *hwmon_dev; 351 struct regmap *regmap; 352 int ret; 353 354 regmap = devm_regmap_init(dev, &max1619_regmap_bus, client, 355 &max1619_regmap_config); 356 if (IS_ERR(regmap)) 357 return PTR_ERR(regmap); 358 359 ret = max1619_init_chip(regmap); 360 if (ret) 361 return ret; 362 363 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, 364 regmap, &max1619_chip_info, NULL); 365 return PTR_ERR_OR_ZERO(hwmon_dev); 366 } 367 368 static const struct i2c_device_id max1619_id[] = { 369 { "max1619" }, 370 { } 371 }; 372 MODULE_DEVICE_TABLE(i2c, max1619_id); 373 374 #ifdef CONFIG_OF 375 static const struct of_device_id max1619_of_match[] = { 376 { .compatible = "maxim,max1619", }, 377 {}, 378 }; 379 380 MODULE_DEVICE_TABLE(of, max1619_of_match); 381 #endif 382 383 static struct i2c_driver max1619_driver = { 384 .class = I2C_CLASS_HWMON, 385 .driver = { 386 .name = "max1619", 387 .of_match_table = of_match_ptr(max1619_of_match), 388 }, 389 .probe = max1619_probe, 390 .id_table = max1619_id, 391 .detect = max1619_detect, 392 .address_list = normal_i2c, 393 }; 394 395 module_i2c_driver(max1619_driver); 396 397 MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>"); 398 MODULE_DESCRIPTION("MAX1619 sensor driver"); 399 MODULE_LICENSE("GPL"); 400