1 /* 2 * max6639.c - Support for Maxim MAX6639 3 * 4 * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller 5 * 6 * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de> 7 * 8 * based on the initial MAX6639 support from semptian.net 9 * by He Changqing <hechangqing@semptian.com> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 24 */ 25 26 #include <linux/module.h> 27 #include <linux/init.h> 28 #include <linux/slab.h> 29 #include <linux/jiffies.h> 30 #include <linux/i2c.h> 31 #include <linux/hwmon.h> 32 #include <linux/hwmon-sysfs.h> 33 #include <linux/err.h> 34 #include <linux/mutex.h> 35 #include <linux/i2c/max6639.h> 36 37 /* Addresses to scan */ 38 static unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END }; 39 40 /* The MAX6639 registers, valid channel numbers: 0, 1 */ 41 #define MAX6639_REG_TEMP(ch) (0x00 + (ch)) 42 #define MAX6639_REG_STATUS 0x02 43 #define MAX6639_REG_OUTPUT_MASK 0x03 44 #define MAX6639_REG_GCONFIG 0x04 45 #define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch)) 46 #define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch)) 47 #define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch)) 48 #define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch)) 49 #define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4) 50 #define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4) 51 #define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4) 52 #define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4) 53 #define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch)) 54 #define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch)) 55 #define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch)) 56 #define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch)) 57 #define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch)) 58 #define MAX6639_REG_DEVID 0x3D 59 #define MAX6639_REG_MANUID 0x3E 60 #define MAX6639_REG_DEVREV 0x3F 61 62 /* Register bits */ 63 #define MAX6639_GCONFIG_STANDBY 0x80 64 #define MAX6639_GCONFIG_POR 0x40 65 #define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20 66 #define MAX6639_GCONFIG_CH2_LOCAL 0x10 67 #define MAX6639_GCONFIG_PWM_FREQ_HI 0x08 68 69 #define MAX6639_FAN_CONFIG1_PWM 0x80 70 71 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40 72 73 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 }; 74 75 #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \ 76 0 : (rpm_ranges[rpm_range] * 30) / (val)) 77 #define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255) 78 79 /* 80 * Client data (each client gets its own) 81 */ 82 struct max6639_data { 83 struct i2c_client *client; 84 struct mutex update_lock; 85 char valid; /* !=0 if following fields are valid */ 86 unsigned long last_updated; /* In jiffies */ 87 88 /* Register values sampled regularly */ 89 u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */ 90 bool temp_fault[2]; /* Detected temperature diode failure */ 91 u8 fan[2]; /* Register value: TACH count for fans >=30 */ 92 u8 status; /* Detected channel alarms and fan failures */ 93 94 /* Register values only written to */ 95 u8 pwm[2]; /* Register value: Duty cycle 0..120 */ 96 u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */ 97 u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */ 98 u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */ 99 100 /* Register values initialized only once */ 101 u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */ 102 u8 rpm_range; /* Index in above rpm_ranges table */ 103 }; 104 105 static struct max6639_data *max6639_update_device(struct device *dev) 106 { 107 struct max6639_data *data = dev_get_drvdata(dev); 108 struct i2c_client *client = data->client; 109 struct max6639_data *ret = data; 110 int i; 111 int status_reg; 112 113 mutex_lock(&data->update_lock); 114 115 if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) { 116 int res; 117 118 dev_dbg(&client->dev, "Starting max6639 update\n"); 119 120 status_reg = i2c_smbus_read_byte_data(client, 121 MAX6639_REG_STATUS); 122 if (status_reg < 0) { 123 ret = ERR_PTR(status_reg); 124 goto abort; 125 } 126 127 data->status = status_reg; 128 129 for (i = 0; i < 2; i++) { 130 res = i2c_smbus_read_byte_data(client, 131 MAX6639_REG_FAN_CNT(i)); 132 if (res < 0) { 133 ret = ERR_PTR(res); 134 goto abort; 135 } 136 data->fan[i] = res; 137 138 res = i2c_smbus_read_byte_data(client, 139 MAX6639_REG_TEMP_EXT(i)); 140 if (res < 0) { 141 ret = ERR_PTR(res); 142 goto abort; 143 } 144 data->temp[i] = res >> 5; 145 data->temp_fault[i] = res & 0x01; 146 147 res = i2c_smbus_read_byte_data(client, 148 MAX6639_REG_TEMP(i)); 149 if (res < 0) { 150 ret = ERR_PTR(res); 151 goto abort; 152 } 153 data->temp[i] |= res << 3; 154 } 155 156 data->last_updated = jiffies; 157 data->valid = 1; 158 } 159 abort: 160 mutex_unlock(&data->update_lock); 161 162 return ret; 163 } 164 165 static ssize_t show_temp_input(struct device *dev, 166 struct device_attribute *dev_attr, char *buf) 167 { 168 long temp; 169 struct max6639_data *data = max6639_update_device(dev); 170 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 171 172 if (IS_ERR(data)) 173 return PTR_ERR(data); 174 175 temp = data->temp[attr->index] * 125; 176 return sprintf(buf, "%ld\n", temp); 177 } 178 179 static ssize_t show_temp_fault(struct device *dev, 180 struct device_attribute *dev_attr, char *buf) 181 { 182 struct max6639_data *data = max6639_update_device(dev); 183 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 184 185 if (IS_ERR(data)) 186 return PTR_ERR(data); 187 188 return sprintf(buf, "%d\n", data->temp_fault[attr->index]); 189 } 190 191 static ssize_t show_temp_max(struct device *dev, 192 struct device_attribute *dev_attr, char *buf) 193 { 194 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 195 struct max6639_data *data = dev_get_drvdata(dev); 196 197 return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000)); 198 } 199 200 static ssize_t set_temp_max(struct device *dev, 201 struct device_attribute *dev_attr, 202 const char *buf, size_t count) 203 { 204 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 205 struct max6639_data *data = dev_get_drvdata(dev); 206 struct i2c_client *client = data->client; 207 unsigned long val; 208 int res; 209 210 res = kstrtoul(buf, 10, &val); 211 if (res) 212 return res; 213 214 mutex_lock(&data->update_lock); 215 data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val); 216 i2c_smbus_write_byte_data(client, 217 MAX6639_REG_THERM_LIMIT(attr->index), 218 data->temp_therm[attr->index]); 219 mutex_unlock(&data->update_lock); 220 return count; 221 } 222 223 static ssize_t show_temp_crit(struct device *dev, 224 struct device_attribute *dev_attr, char *buf) 225 { 226 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 227 struct max6639_data *data = dev_get_drvdata(dev); 228 229 return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000)); 230 } 231 232 static ssize_t set_temp_crit(struct device *dev, 233 struct device_attribute *dev_attr, 234 const char *buf, size_t count) 235 { 236 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 237 struct max6639_data *data = dev_get_drvdata(dev); 238 struct i2c_client *client = data->client; 239 unsigned long val; 240 int res; 241 242 res = kstrtoul(buf, 10, &val); 243 if (res) 244 return res; 245 246 mutex_lock(&data->update_lock); 247 data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val); 248 i2c_smbus_write_byte_data(client, 249 MAX6639_REG_ALERT_LIMIT(attr->index), 250 data->temp_alert[attr->index]); 251 mutex_unlock(&data->update_lock); 252 return count; 253 } 254 255 static ssize_t show_temp_emergency(struct device *dev, 256 struct device_attribute *dev_attr, 257 char *buf) 258 { 259 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 260 struct max6639_data *data = dev_get_drvdata(dev); 261 262 return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000)); 263 } 264 265 static ssize_t set_temp_emergency(struct device *dev, 266 struct device_attribute *dev_attr, 267 const char *buf, size_t count) 268 { 269 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 270 struct max6639_data *data = dev_get_drvdata(dev); 271 struct i2c_client *client = data->client; 272 unsigned long val; 273 int res; 274 275 res = kstrtoul(buf, 10, &val); 276 if (res) 277 return res; 278 279 mutex_lock(&data->update_lock); 280 data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val); 281 i2c_smbus_write_byte_data(client, 282 MAX6639_REG_OT_LIMIT(attr->index), 283 data->temp_ot[attr->index]); 284 mutex_unlock(&data->update_lock); 285 return count; 286 } 287 288 static ssize_t show_pwm(struct device *dev, 289 struct device_attribute *dev_attr, char *buf) 290 { 291 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 292 struct max6639_data *data = dev_get_drvdata(dev); 293 294 return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120); 295 } 296 297 static ssize_t set_pwm(struct device *dev, 298 struct device_attribute *dev_attr, 299 const char *buf, size_t count) 300 { 301 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 302 struct max6639_data *data = dev_get_drvdata(dev); 303 struct i2c_client *client = data->client; 304 unsigned long val; 305 int res; 306 307 res = kstrtoul(buf, 10, &val); 308 if (res) 309 return res; 310 311 val = clamp_val(val, 0, 255); 312 313 mutex_lock(&data->update_lock); 314 data->pwm[attr->index] = (u8)(val * 120 / 255); 315 i2c_smbus_write_byte_data(client, 316 MAX6639_REG_TARGTDUTY(attr->index), 317 data->pwm[attr->index]); 318 mutex_unlock(&data->update_lock); 319 return count; 320 } 321 322 static ssize_t show_fan_input(struct device *dev, 323 struct device_attribute *dev_attr, char *buf) 324 { 325 struct max6639_data *data = max6639_update_device(dev); 326 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 327 328 if (IS_ERR(data)) 329 return PTR_ERR(data); 330 331 return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index], 332 data->rpm_range)); 333 } 334 335 static ssize_t show_alarm(struct device *dev, 336 struct device_attribute *dev_attr, char *buf) 337 { 338 struct max6639_data *data = max6639_update_device(dev); 339 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 340 341 if (IS_ERR(data)) 342 return PTR_ERR(data); 343 344 return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index))); 345 } 346 347 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0); 348 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input, NULL, 1); 349 static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_temp_fault, NULL, 0); 350 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_temp_fault, NULL, 1); 351 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max, 352 set_temp_max, 0); 353 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max, 354 set_temp_max, 1); 355 static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_crit, 356 set_temp_crit, 0); 357 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit, 358 set_temp_crit, 1); 359 static SENSOR_DEVICE_ATTR(temp1_emergency, S_IWUSR | S_IRUGO, 360 show_temp_emergency, set_temp_emergency, 0); 361 static SENSOR_DEVICE_ATTR(temp2_emergency, S_IWUSR | S_IRUGO, 362 show_temp_emergency, set_temp_emergency, 1); 363 static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 0); 364 static SENSOR_DEVICE_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 1); 365 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input, NULL, 0); 366 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input, NULL, 1); 367 static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_alarm, NULL, 1); 368 static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_alarm, NULL, 0); 369 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 3); 370 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 2); 371 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 7); 372 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 6); 373 static SENSOR_DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO, show_alarm, NULL, 5); 374 static SENSOR_DEVICE_ATTR(temp2_emergency_alarm, S_IRUGO, show_alarm, NULL, 4); 375 376 377 static struct attribute *max6639_attrs[] = { 378 &sensor_dev_attr_temp1_input.dev_attr.attr, 379 &sensor_dev_attr_temp2_input.dev_attr.attr, 380 &sensor_dev_attr_temp1_fault.dev_attr.attr, 381 &sensor_dev_attr_temp2_fault.dev_attr.attr, 382 &sensor_dev_attr_temp1_max.dev_attr.attr, 383 &sensor_dev_attr_temp2_max.dev_attr.attr, 384 &sensor_dev_attr_temp1_crit.dev_attr.attr, 385 &sensor_dev_attr_temp2_crit.dev_attr.attr, 386 &sensor_dev_attr_temp1_emergency.dev_attr.attr, 387 &sensor_dev_attr_temp2_emergency.dev_attr.attr, 388 &sensor_dev_attr_pwm1.dev_attr.attr, 389 &sensor_dev_attr_pwm2.dev_attr.attr, 390 &sensor_dev_attr_fan1_input.dev_attr.attr, 391 &sensor_dev_attr_fan2_input.dev_attr.attr, 392 &sensor_dev_attr_fan1_fault.dev_attr.attr, 393 &sensor_dev_attr_fan2_fault.dev_attr.attr, 394 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 395 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 396 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 397 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 398 &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr, 399 &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr, 400 NULL 401 }; 402 ATTRIBUTE_GROUPS(max6639); 403 404 /* 405 * returns respective index in rpm_ranges table 406 * 1 by default on invalid range 407 */ 408 static int rpm_range_to_reg(int range) 409 { 410 int i; 411 412 for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) { 413 if (rpm_ranges[i] == range) 414 return i; 415 } 416 417 return 1; /* default: 4000 RPM */ 418 } 419 420 static int max6639_init_client(struct i2c_client *client, 421 struct max6639_data *data) 422 { 423 struct max6639_platform_data *max6639_info = 424 dev_get_platdata(&client->dev); 425 int i; 426 int rpm_range = 1; /* default: 4000 RPM */ 427 int err; 428 429 /* Reset chip to default values, see below for GCONFIG setup */ 430 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, 431 MAX6639_GCONFIG_POR); 432 if (err) 433 goto exit; 434 435 /* Fans pulse per revolution is 2 by default */ 436 if (max6639_info && max6639_info->ppr > 0 && 437 max6639_info->ppr < 5) 438 data->ppr = max6639_info->ppr; 439 else 440 data->ppr = 2; 441 data->ppr -= 1; 442 443 if (max6639_info) 444 rpm_range = rpm_range_to_reg(max6639_info->rpm_range); 445 data->rpm_range = rpm_range; 446 447 for (i = 0; i < 2; i++) { 448 449 /* Set Fan pulse per revolution */ 450 err = i2c_smbus_write_byte_data(client, 451 MAX6639_REG_FAN_PPR(i), 452 data->ppr << 6); 453 if (err) 454 goto exit; 455 456 /* Fans config PWM, RPM */ 457 err = i2c_smbus_write_byte_data(client, 458 MAX6639_REG_FAN_CONFIG1(i), 459 MAX6639_FAN_CONFIG1_PWM | rpm_range); 460 if (err) 461 goto exit; 462 463 /* Fans PWM polarity high by default */ 464 if (max6639_info && max6639_info->pwm_polarity == 0) 465 err = i2c_smbus_write_byte_data(client, 466 MAX6639_REG_FAN_CONFIG2a(i), 0x00); 467 else 468 err = i2c_smbus_write_byte_data(client, 469 MAX6639_REG_FAN_CONFIG2a(i), 0x02); 470 if (err) 471 goto exit; 472 473 /* 474 * /THERM full speed enable, 475 * PWM frequency 25kHz, see also GCONFIG below 476 */ 477 err = i2c_smbus_write_byte_data(client, 478 MAX6639_REG_FAN_CONFIG3(i), 479 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03); 480 if (err) 481 goto exit; 482 483 /* Max. temp. 80C/90C/100C */ 484 data->temp_therm[i] = 80; 485 data->temp_alert[i] = 90; 486 data->temp_ot[i] = 100; 487 err = i2c_smbus_write_byte_data(client, 488 MAX6639_REG_THERM_LIMIT(i), 489 data->temp_therm[i]); 490 if (err) 491 goto exit; 492 err = i2c_smbus_write_byte_data(client, 493 MAX6639_REG_ALERT_LIMIT(i), 494 data->temp_alert[i]); 495 if (err) 496 goto exit; 497 err = i2c_smbus_write_byte_data(client, 498 MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]); 499 if (err) 500 goto exit; 501 502 /* PWM 120/120 (i.e. 100%) */ 503 data->pwm[i] = 120; 504 err = i2c_smbus_write_byte_data(client, 505 MAX6639_REG_TARGTDUTY(i), data->pwm[i]); 506 if (err) 507 goto exit; 508 } 509 /* Start monitoring */ 510 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, 511 MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL | 512 MAX6639_GCONFIG_PWM_FREQ_HI); 513 exit: 514 return err; 515 } 516 517 /* Return 0 if detection is successful, -ENODEV otherwise */ 518 static int max6639_detect(struct i2c_client *client, 519 struct i2c_board_info *info) 520 { 521 struct i2c_adapter *adapter = client->adapter; 522 int dev_id, manu_id; 523 524 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 525 return -ENODEV; 526 527 /* Actual detection via device and manufacturer ID */ 528 dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID); 529 manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID); 530 if (dev_id != 0x58 || manu_id != 0x4D) 531 return -ENODEV; 532 533 strlcpy(info->type, "max6639", I2C_NAME_SIZE); 534 535 return 0; 536 } 537 538 static int max6639_probe(struct i2c_client *client, 539 const struct i2c_device_id *id) 540 { 541 struct device *dev = &client->dev; 542 struct max6639_data *data; 543 struct device *hwmon_dev; 544 int err; 545 546 data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL); 547 if (!data) 548 return -ENOMEM; 549 550 data->client = client; 551 mutex_init(&data->update_lock); 552 553 /* Initialize the max6639 chip */ 554 err = max6639_init_client(client, data); 555 if (err < 0) 556 return err; 557 558 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, 559 data, 560 max6639_groups); 561 return PTR_ERR_OR_ZERO(hwmon_dev); 562 } 563 564 #ifdef CONFIG_PM_SLEEP 565 static int max6639_suspend(struct device *dev) 566 { 567 struct i2c_client *client = to_i2c_client(dev); 568 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG); 569 if (data < 0) 570 return data; 571 572 return i2c_smbus_write_byte_data(client, 573 MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY); 574 } 575 576 static int max6639_resume(struct device *dev) 577 { 578 struct i2c_client *client = to_i2c_client(dev); 579 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG); 580 if (data < 0) 581 return data; 582 583 return i2c_smbus_write_byte_data(client, 584 MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY); 585 } 586 #endif /* CONFIG_PM_SLEEP */ 587 588 static const struct i2c_device_id max6639_id[] = { 589 {"max6639", 0}, 590 { } 591 }; 592 593 MODULE_DEVICE_TABLE(i2c, max6639_id); 594 595 static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume); 596 597 static struct i2c_driver max6639_driver = { 598 .class = I2C_CLASS_HWMON, 599 .driver = { 600 .name = "max6639", 601 .pm = &max6639_pm_ops, 602 }, 603 .probe = max6639_probe, 604 .id_table = max6639_id, 605 .detect = max6639_detect, 606 .address_list = normal_i2c, 607 }; 608 609 module_i2c_driver(max6639_driver); 610 611 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>"); 612 MODULE_DESCRIPTION("max6639 driver"); 613 MODULE_LICENSE("GPL"); 614