1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Device driver for the i2c thermostat found on the iBook G4, Albook G4 4 * 5 * Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt 6 * 7 * Documentation from 115254175ADT7467_pra.pdf and 3686221171167ADT7460_b.pdf 8 * https://www.onsemi.com/PowerSolutions/product.do?id=ADT7467 9 * https://www.onsemi.com/PowerSolutions/product.do?id=ADT7460 10 * 11 */ 12 13 #include <linux/types.h> 14 #include <linux/module.h> 15 #include <linux/errno.h> 16 #include <linux/kernel.h> 17 #include <linux/delay.h> 18 #include <linux/sched.h> 19 #include <linux/i2c.h> 20 #include <linux/slab.h> 21 #include <linux/init.h> 22 #include <linux/spinlock.h> 23 #include <linux/wait.h> 24 #include <linux/suspend.h> 25 #include <linux/kthread.h> 26 #include <linux/moduleparam.h> 27 #include <linux/freezer.h> 28 #include <linux/of_platform.h> 29 30 #include <asm/prom.h> 31 #include <asm/machdep.h> 32 #include <asm/io.h> 33 #include <asm/sections.h> 34 35 #undef DEBUG 36 37 #define CONFIG_REG 0x40 38 #define MANUAL_MASK 0xe0 39 #define AUTO_MASK 0x20 40 #define INVERT_MASK 0x10 41 42 static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */ 43 static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */ 44 static u8 MANUAL_MODE[2] = {0x5c, 0x5d}; 45 static u8 REM_CONTROL[2] = {0x00, 0x40}; 46 static u8 FAN_SPEED[2] = {0x28, 0x2a}; 47 static u8 FAN_SPD_SET[2] = {0x30, 0x31}; 48 49 static u8 default_limits_local[3] = {70, 50, 70}; /* local, sensor1, sensor2 */ 50 static u8 default_limits_chip[3] = {80, 65, 80}; /* local, sensor1, sensor2 */ 51 static const char *sensor_location[3] = { "?", "?", "?" }; 52 53 static int limit_adjust; 54 static int fan_speed = -1; 55 static bool verbose; 56 57 MODULE_AUTHOR("Colin Leroy <colin@colino.net>"); 58 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and " 59 "Powerbook G4 Alu"); 60 MODULE_LICENSE("GPL"); 61 62 module_param(limit_adjust, int, 0644); 63 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) " 64 "by N degrees."); 65 66 module_param(fan_speed, int, 0644); 67 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) " 68 "(default 64)"); 69 70 module_param(verbose, bool, 0); 71 MODULE_PARM_DESC(verbose,"Verbose log operations " 72 "(default 0)"); 73 74 struct thermostat { 75 struct i2c_client *clt; 76 u8 temps[3]; 77 u8 cached_temp[3]; 78 u8 initial_limits[3]; 79 u8 limits[3]; 80 int last_speed[2]; 81 int last_var[2]; 82 int pwm_inv[2]; 83 struct task_struct *thread; 84 struct platform_device *pdev; 85 enum { 86 ADT7460, 87 ADT7467 88 } type; 89 }; 90 91 static void write_both_fan_speed(struct thermostat *th, int speed); 92 static void write_fan_speed(struct thermostat *th, int speed, int fan); 93 94 static int 95 write_reg(struct thermostat* th, int reg, u8 data) 96 { 97 u8 tmp[2]; 98 int rc; 99 100 tmp[0] = reg; 101 tmp[1] = data; 102 rc = i2c_master_send(th->clt, (const char *)tmp, 2); 103 if (rc < 0) 104 return rc; 105 if (rc != 2) 106 return -ENODEV; 107 return 0; 108 } 109 110 static int 111 read_reg(struct thermostat* th, int reg) 112 { 113 u8 reg_addr, data; 114 int rc; 115 116 reg_addr = (u8)reg; 117 rc = i2c_master_send(th->clt, ®_addr, 1); 118 if (rc < 0) 119 return rc; 120 if (rc != 1) 121 return -ENODEV; 122 rc = i2c_master_recv(th->clt, (char *)&data, 1); 123 if (rc < 0) 124 return rc; 125 return data; 126 } 127 128 static int read_fan_speed(struct thermostat *th, u8 addr) 129 { 130 u8 tmp[2]; 131 u16 res; 132 133 /* should start with low byte */ 134 tmp[1] = read_reg(th, addr); 135 tmp[0] = read_reg(th, addr + 1); 136 137 res = tmp[1] + (tmp[0] << 8); 138 /* "a value of 0xffff means that the fan has stopped" */ 139 return (res == 0xffff ? 0 : (90000*60)/res); 140 } 141 142 static void write_both_fan_speed(struct thermostat *th, int speed) 143 { 144 write_fan_speed(th, speed, 0); 145 if (th->type == ADT7460) 146 write_fan_speed(th, speed, 1); 147 } 148 149 static void write_fan_speed(struct thermostat *th, int speed, int fan) 150 { 151 u8 manual; 152 153 if (speed > 0xff) 154 speed = 0xff; 155 else if (speed < -1) 156 speed = 0; 157 158 if (th->type == ADT7467 && fan == 1) 159 return; 160 161 if (th->last_speed[fan] != speed) { 162 if (verbose) { 163 if (speed == -1) 164 printk(KERN_DEBUG "adt746x: Setting speed to automatic " 165 "for %s fan.\n", sensor_location[fan+1]); 166 else 167 printk(KERN_DEBUG "adt746x: Setting speed to %d " 168 "for %s fan.\n", speed, sensor_location[fan+1]); 169 } 170 } else 171 return; 172 173 if (speed >= 0) { 174 manual = read_reg(th, MANUAL_MODE[fan]); 175 manual &= ~INVERT_MASK; 176 write_reg(th, MANUAL_MODE[fan], 177 manual | MANUAL_MASK | th->pwm_inv[fan]); 178 write_reg(th, FAN_SPD_SET[fan], speed); 179 } else { 180 /* back to automatic */ 181 if(th->type == ADT7460) { 182 manual = read_reg(th, 183 MANUAL_MODE[fan]) & (~MANUAL_MASK); 184 manual &= ~INVERT_MASK; 185 manual |= th->pwm_inv[fan]; 186 write_reg(th, 187 MANUAL_MODE[fan], manual|REM_CONTROL[fan]); 188 } else { 189 manual = read_reg(th, MANUAL_MODE[fan]); 190 manual &= ~INVERT_MASK; 191 manual |= th->pwm_inv[fan]; 192 write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK)); 193 } 194 } 195 196 th->last_speed[fan] = speed; 197 } 198 199 static void read_sensors(struct thermostat *th) 200 { 201 int i = 0; 202 203 for (i = 0; i < 3; i++) 204 th->temps[i] = read_reg(th, TEMP_REG[i]); 205 } 206 207 #ifdef DEBUG 208 static void display_stats(struct thermostat *th) 209 { 210 if (th->temps[0] != th->cached_temp[0] 211 || th->temps[1] != th->cached_temp[1] 212 || th->temps[2] != th->cached_temp[2]) { 213 printk(KERN_INFO "adt746x: Temperature infos:" 214 " thermostats: %d,%d,%d;" 215 " limits: %d,%d,%d;" 216 " fan speed: %d RPM\n", 217 th->temps[0], th->temps[1], th->temps[2], 218 th->limits[0], th->limits[1], th->limits[2], 219 read_fan_speed(th, FAN_SPEED[0])); 220 } 221 th->cached_temp[0] = th->temps[0]; 222 th->cached_temp[1] = th->temps[1]; 223 th->cached_temp[2] = th->temps[2]; 224 } 225 #endif 226 227 static void update_fans_speed (struct thermostat *th) 228 { 229 int lastvar = 0; /* last variation, for iBook */ 230 int i = 0; 231 232 /* we don't care about local sensor, so we start at sensor 1 */ 233 for (i = 1; i < 3; i++) { 234 bool started = false; 235 int fan_number = (th->type == ADT7460 && i == 2); 236 int var = th->temps[i] - th->limits[i]; 237 238 if (var > -1) { 239 int step = (255 - fan_speed) / 7; 240 int new_speed = 0; 241 242 /* hysteresis : change fan speed only if variation is 243 * more than two degrees */ 244 if (abs(var - th->last_var[fan_number]) < 2) 245 continue; 246 247 started = true; 248 new_speed = fan_speed + ((var-1)*step); 249 250 if (new_speed < fan_speed) 251 new_speed = fan_speed; 252 if (new_speed > 255) 253 new_speed = 255; 254 255 if (verbose) 256 printk(KERN_DEBUG "adt746x: Setting fans speed to %d " 257 "(limit exceeded by %d on %s)\n", 258 new_speed, var, 259 sensor_location[fan_number+1]); 260 write_both_fan_speed(th, new_speed); 261 th->last_var[fan_number] = var; 262 } else if (var < -2) { 263 /* don't stop fan if sensor2 is cold and sensor1 is not 264 * so cold (lastvar >= -1) */ 265 if (i == 2 && lastvar < -1) { 266 if (th->last_speed[fan_number] != 0) 267 if (verbose) 268 printk(KERN_DEBUG "adt746x: Stopping " 269 "fans.\n"); 270 write_both_fan_speed(th, 0); 271 } 272 } 273 274 lastvar = var; 275 276 if (started) 277 return; /* we don't want to re-stop the fan 278 * if sensor1 is heating and sensor2 is not */ 279 } 280 } 281 282 static int monitor_task(void *arg) 283 { 284 struct thermostat* th = arg; 285 286 set_freezable(); 287 while(!kthread_should_stop()) { 288 try_to_freeze(); 289 msleep_interruptible(2000); 290 291 #ifndef DEBUG 292 if (fan_speed != -1) 293 read_sensors(th); 294 #else 295 read_sensors(th); 296 #endif 297 298 if (fan_speed != -1) 299 update_fans_speed(th); 300 301 #ifdef DEBUG 302 display_stats(th); 303 #endif 304 305 } 306 307 return 0; 308 } 309 310 static void set_limit(struct thermostat *th, int i) 311 { 312 /* Set sensor1 limit higher to avoid powerdowns */ 313 th->limits[i] = default_limits_chip[i] + limit_adjust; 314 write_reg(th, LIMIT_REG[i], th->limits[i]); 315 316 /* set our limits to normal */ 317 th->limits[i] = default_limits_local[i] + limit_adjust; 318 } 319 320 #define BUILD_SHOW_FUNC_INT(name, data) \ 321 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \ 322 { \ 323 struct thermostat *th = dev_get_drvdata(dev); \ 324 return sprintf(buf, "%d\n", data); \ 325 } 326 327 #define BUILD_SHOW_FUNC_INT_LITE(name, data) \ 328 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \ 329 { \ 330 return sprintf(buf, "%d\n", data); \ 331 } 332 333 #define BUILD_SHOW_FUNC_STR(name, data) \ 334 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \ 335 { \ 336 return sprintf(buf, "%s\n", data); \ 337 } 338 339 #define BUILD_SHOW_FUNC_FAN(name, data) \ 340 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \ 341 { \ 342 struct thermostat *th = dev_get_drvdata(dev); \ 343 return sprintf(buf, "%d (%d rpm)\n", \ 344 th->last_speed[data], \ 345 read_fan_speed(th, FAN_SPEED[data]) \ 346 ); \ 347 } 348 349 #define BUILD_STORE_FUNC_DEG(name, data) \ 350 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \ 351 { \ 352 struct thermostat *th = dev_get_drvdata(dev); \ 353 int val; \ 354 int i; \ 355 val = simple_strtol(buf, NULL, 10); \ 356 printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \ 357 limit_adjust = val; \ 358 for (i=0; i < 3; i++) \ 359 set_limit(th, i); \ 360 return n; \ 361 } 362 363 #define BUILD_STORE_FUNC_INT(name, data) \ 364 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \ 365 { \ 366 int val; \ 367 val = simple_strtol(buf, NULL, 10); \ 368 if (val < 0 || val > 255) \ 369 return -EINVAL; \ 370 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \ 371 data = val; \ 372 return n; \ 373 } 374 375 BUILD_SHOW_FUNC_INT(sensor1_temperature, (read_reg(th, TEMP_REG[1]))) 376 BUILD_SHOW_FUNC_INT(sensor2_temperature, (read_reg(th, TEMP_REG[2]))) 377 BUILD_SHOW_FUNC_INT(sensor1_limit, th->limits[1]) 378 BUILD_SHOW_FUNC_INT(sensor2_limit, th->limits[2]) 379 BUILD_SHOW_FUNC_STR(sensor1_location, sensor_location[1]) 380 BUILD_SHOW_FUNC_STR(sensor2_location, sensor_location[2]) 381 382 BUILD_SHOW_FUNC_INT_LITE(specified_fan_speed, fan_speed) 383 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed) 384 385 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed, 0) 386 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed, 1) 387 388 BUILD_SHOW_FUNC_INT_LITE(limit_adjust, limit_adjust) 389 BUILD_STORE_FUNC_DEG(limit_adjust, th) 390 391 static DEVICE_ATTR(sensor1_temperature, S_IRUGO, 392 show_sensor1_temperature,NULL); 393 static DEVICE_ATTR(sensor2_temperature, S_IRUGO, 394 show_sensor2_temperature,NULL); 395 static DEVICE_ATTR(sensor1_limit, S_IRUGO, 396 show_sensor1_limit, NULL); 397 static DEVICE_ATTR(sensor2_limit, S_IRUGO, 398 show_sensor2_limit, NULL); 399 static DEVICE_ATTR(sensor1_location, S_IRUGO, 400 show_sensor1_location, NULL); 401 static DEVICE_ATTR(sensor2_location, S_IRUGO, 402 show_sensor2_location, NULL); 403 404 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH, 405 show_specified_fan_speed,store_specified_fan_speed); 406 407 static DEVICE_ATTR(sensor1_fan_speed, S_IRUGO, 408 show_sensor1_fan_speed, NULL); 409 static DEVICE_ATTR(sensor2_fan_speed, S_IRUGO, 410 show_sensor2_fan_speed, NULL); 411 412 static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH, 413 show_limit_adjust, store_limit_adjust); 414 415 static void thermostat_create_files(struct thermostat *th) 416 { 417 struct device_node *np = th->clt->dev.of_node; 418 struct device *dev; 419 int err; 420 421 /* To maintain ABI compatibility with userspace, create 422 * the old style platform driver and attach the attributes 423 * to it here 424 */ 425 th->pdev = of_platform_device_create(np, "temperatures", NULL); 426 if (!th->pdev) 427 return; 428 dev = &th->pdev->dev; 429 dev_set_drvdata(dev, th); 430 err = device_create_file(dev, &dev_attr_sensor1_temperature); 431 err |= device_create_file(dev, &dev_attr_sensor2_temperature); 432 err |= device_create_file(dev, &dev_attr_sensor1_limit); 433 err |= device_create_file(dev, &dev_attr_sensor2_limit); 434 err |= device_create_file(dev, &dev_attr_sensor1_location); 435 err |= device_create_file(dev, &dev_attr_sensor2_location); 436 err |= device_create_file(dev, &dev_attr_limit_adjust); 437 err |= device_create_file(dev, &dev_attr_specified_fan_speed); 438 err |= device_create_file(dev, &dev_attr_sensor1_fan_speed); 439 if(th->type == ADT7460) 440 err |= device_create_file(dev, &dev_attr_sensor2_fan_speed); 441 if (err) 442 printk(KERN_WARNING 443 "Failed to create temperature attribute file(s).\n"); 444 } 445 446 static void thermostat_remove_files(struct thermostat *th) 447 { 448 struct device *dev; 449 450 if (!th->pdev) 451 return; 452 dev = &th->pdev->dev; 453 device_remove_file(dev, &dev_attr_sensor1_temperature); 454 device_remove_file(dev, &dev_attr_sensor2_temperature); 455 device_remove_file(dev, &dev_attr_sensor1_limit); 456 device_remove_file(dev, &dev_attr_sensor2_limit); 457 device_remove_file(dev, &dev_attr_sensor1_location); 458 device_remove_file(dev, &dev_attr_sensor2_location); 459 device_remove_file(dev, &dev_attr_limit_adjust); 460 device_remove_file(dev, &dev_attr_specified_fan_speed); 461 device_remove_file(dev, &dev_attr_sensor1_fan_speed); 462 if (th->type == ADT7460) 463 device_remove_file(dev, &dev_attr_sensor2_fan_speed); 464 of_device_unregister(th->pdev); 465 466 } 467 468 static int probe_thermostat(struct i2c_client *client, 469 const struct i2c_device_id *id) 470 { 471 struct device_node *np = client->dev.of_node; 472 struct thermostat* th; 473 const __be32 *prop; 474 int i, rc, vers, offset = 0; 475 476 if (!np) 477 return -ENXIO; 478 prop = of_get_property(np, "hwsensor-params-version", NULL); 479 if (!prop) 480 return -ENXIO; 481 vers = be32_to_cpup(prop); 482 printk(KERN_INFO "adt746x: version %d (%ssupported)\n", 483 vers, vers == 1 ? "" : "un"); 484 if (vers != 1) 485 return -ENXIO; 486 487 if (of_get_property(np, "hwsensor-location", NULL)) { 488 for (i = 0; i < 3; i++) { 489 sensor_location[i] = of_get_property(np, 490 "hwsensor-location", NULL) + offset; 491 492 if (sensor_location[i] == NULL) 493 sensor_location[i] = ""; 494 495 printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]); 496 offset += strlen(sensor_location[i]) + 1; 497 } 498 } 499 500 th = kzalloc(sizeof(struct thermostat), GFP_KERNEL); 501 if (!th) 502 return -ENOMEM; 503 504 i2c_set_clientdata(client, th); 505 th->clt = client; 506 th->type = id->driver_data; 507 508 rc = read_reg(th, CONFIG_REG); 509 if (rc < 0) { 510 dev_err(&client->dev, "Thermostat failed to read config!\n"); 511 kfree(th); 512 return -ENODEV; 513 } 514 515 /* force manual control to start the fan quieter */ 516 if (fan_speed == -1) 517 fan_speed = 64; 518 519 if (th->type == ADT7460) { 520 printk(KERN_INFO "adt746x: ADT7460 initializing\n"); 521 /* The 7460 needs to be started explicitly */ 522 write_reg(th, CONFIG_REG, 1); 523 } else 524 printk(KERN_INFO "adt746x: ADT7467 initializing\n"); 525 526 for (i = 0; i < 3; i++) { 527 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]); 528 set_limit(th, i); 529 } 530 531 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d" 532 " to %d, %d, %d\n", 533 th->initial_limits[0], th->initial_limits[1], 534 th->initial_limits[2], th->limits[0], th->limits[1], 535 th->limits[2]); 536 537 /* record invert bit status because fw can corrupt it after suspend */ 538 th->pwm_inv[0] = read_reg(th, MANUAL_MODE[0]) & INVERT_MASK; 539 th->pwm_inv[1] = read_reg(th, MANUAL_MODE[1]) & INVERT_MASK; 540 541 /* be sure to really write fan speed the first time */ 542 th->last_speed[0] = -2; 543 th->last_speed[1] = -2; 544 th->last_var[0] = -80; 545 th->last_var[1] = -80; 546 547 if (fan_speed != -1) { 548 /* manual mode, stop fans */ 549 write_both_fan_speed(th, 0); 550 } else { 551 /* automatic mode */ 552 write_both_fan_speed(th, -1); 553 } 554 555 th->thread = kthread_run(monitor_task, th, "kfand"); 556 if (th->thread == ERR_PTR(-ENOMEM)) { 557 printk(KERN_INFO "adt746x: Kthread creation failed\n"); 558 th->thread = NULL; 559 return -ENOMEM; 560 } 561 562 thermostat_create_files(th); 563 564 return 0; 565 } 566 567 static int remove_thermostat(struct i2c_client *client) 568 { 569 struct thermostat *th = i2c_get_clientdata(client); 570 int i; 571 572 thermostat_remove_files(th); 573 574 if (th->thread != NULL) 575 kthread_stop(th->thread); 576 577 printk(KERN_INFO "adt746x: Putting max temperatures back from " 578 "%d, %d, %d to %d, %d, %d\n", 579 th->limits[0], th->limits[1], th->limits[2], 580 th->initial_limits[0], th->initial_limits[1], 581 th->initial_limits[2]); 582 583 for (i = 0; i < 3; i++) 584 write_reg(th, LIMIT_REG[i], th->initial_limits[i]); 585 586 write_both_fan_speed(th, -1); 587 588 kfree(th); 589 590 return 0; 591 } 592 593 static const struct i2c_device_id therm_adt746x_id[] = { 594 { "MAC,adt7460", ADT7460 }, 595 { "MAC,adt7467", ADT7467 }, 596 { } 597 }; 598 MODULE_DEVICE_TABLE(i2c, therm_adt746x_id); 599 600 static struct i2c_driver thermostat_driver = { 601 .driver = { 602 .name = "therm_adt746x", 603 }, 604 .probe = probe_thermostat, 605 .remove = remove_thermostat, 606 .id_table = therm_adt746x_id, 607 }; 608 609 static int __init thermostat_init(void) 610 { 611 #ifndef CONFIG_I2C_POWERMAC 612 request_module("i2c-powermac"); 613 #endif 614 615 return i2c_add_driver(&thermostat_driver); 616 } 617 618 static void __exit thermostat_exit(void) 619 { 620 i2c_del_driver(&thermostat_driver); 621 } 622 623 module_init(thermostat_init); 624 module_exit(thermostat_exit); 625