1 /* 2 * Device driver for the i2c thermostat found on the iBook G4, Albook G4 3 * 4 * Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt 5 * 6 * Documentation from 7 * http://www.analog.com/UploadedFiles/Data_Sheets/115254175ADT7467_pra.pdf 8 * http://www.analog.com/UploadedFiles/Data_Sheets/3686221171167ADT7460_b.pdf 9 * 10 */ 11 12 #include <linux/config.h> 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/smp_lock.h> 24 #include <linux/wait.h> 25 #include <linux/suspend.h> 26 #include <linux/kthread.h> 27 #include <linux/moduleparam.h> 28 29 #include <asm/prom.h> 30 #include <asm/machdep.h> 31 #include <asm/io.h> 32 #include <asm/system.h> 33 #include <asm/sections.h> 34 #include <asm/of_device.h> 35 36 #undef DEBUG 37 38 #define CONFIG_REG 0x40 39 #define MANUAL_MASK 0xe0 40 #define AUTO_MASK 0x20 41 42 static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, cpu, gpu */ 43 static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, cpu, gpu */ 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, cpu, gpu */ 50 static u8 default_limits_chip[3] = {80, 65, 80}; /* local, cpu, gpu */ 51 52 static int limit_adjust = 0; 53 static int fan_speed = -1; 54 55 MODULE_AUTHOR("Colin Leroy <colin@colino.net>"); 56 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and " 57 "Powerbook G4 Alu"); 58 MODULE_LICENSE("GPL"); 59 60 module_param(limit_adjust, int, 0644); 61 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 cpu, 70 gpu) " 62 "by N degrees."); 63 64 module_param(fan_speed, int, 0644); 65 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) " 66 "(default 64)"); 67 68 struct thermostat { 69 struct i2c_client clt; 70 u8 temps[3]; 71 u8 cached_temp[3]; 72 u8 initial_limits[3]; 73 u8 limits[3]; 74 int last_speed[2]; 75 int last_var[2]; 76 }; 77 78 static enum {ADT7460, ADT7467} therm_type; 79 static int therm_bus, therm_address; 80 static struct of_device * of_dev; 81 static struct thermostat* thermostat; 82 static struct task_struct *thread_therm = NULL; 83 84 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr, 85 int busno); 86 87 static void write_both_fan_speed(struct thermostat *th, int speed); 88 static void write_fan_speed(struct thermostat *th, int speed, int fan); 89 90 static int 91 write_reg(struct thermostat* th, int reg, u8 data) 92 { 93 u8 tmp[2]; 94 int rc; 95 96 tmp[0] = reg; 97 tmp[1] = data; 98 rc = i2c_master_send(&th->clt, (const char *)tmp, 2); 99 if (rc < 0) 100 return rc; 101 if (rc != 2) 102 return -ENODEV; 103 return 0; 104 } 105 106 static int 107 read_reg(struct thermostat* th, int reg) 108 { 109 u8 reg_addr, data; 110 int rc; 111 112 reg_addr = (u8)reg; 113 rc = i2c_master_send(&th->clt, ®_addr, 1); 114 if (rc < 0) 115 return rc; 116 if (rc != 1) 117 return -ENODEV; 118 rc = i2c_master_recv(&th->clt, (char *)&data, 1); 119 if (rc < 0) 120 return rc; 121 return data; 122 } 123 124 static int 125 attach_thermostat(struct i2c_adapter *adapter) 126 { 127 unsigned long bus_no; 128 129 if (strncmp(adapter->name, "uni-n", 5)) 130 return -ENODEV; 131 bus_no = simple_strtoul(adapter->name + 6, NULL, 10); 132 if (bus_no != therm_bus) 133 return -ENODEV; 134 return attach_one_thermostat(adapter, therm_address, bus_no); 135 } 136 137 static int 138 detach_thermostat(struct i2c_adapter *adapter) 139 { 140 struct thermostat* th; 141 int i; 142 143 if (thermostat == NULL) 144 return 0; 145 146 th = thermostat; 147 148 if (thread_therm != NULL) { 149 kthread_stop(thread_therm); 150 } 151 152 printk(KERN_INFO "adt746x: Putting max temperatures back from " 153 "%d, %d, %d to %d, %d, %d\n", 154 th->limits[0], th->limits[1], th->limits[2], 155 th->initial_limits[0], th->initial_limits[1], 156 th->initial_limits[2]); 157 158 for (i = 0; i < 3; i++) 159 write_reg(th, LIMIT_REG[i], th->initial_limits[i]); 160 161 write_both_fan_speed(th, -1); 162 163 i2c_detach_client(&th->clt); 164 165 thermostat = NULL; 166 167 kfree(th); 168 169 return 0; 170 } 171 172 static struct i2c_driver thermostat_driver = { 173 .owner = THIS_MODULE, 174 .name = "therm_adt746x", 175 .flags = I2C_DF_NOTIFY, 176 .attach_adapter = attach_thermostat, 177 .detach_adapter = detach_thermostat, 178 }; 179 180 static int read_fan_speed(struct thermostat *th, u8 addr) 181 { 182 u8 tmp[2]; 183 u16 res; 184 185 /* should start with low byte */ 186 tmp[1] = read_reg(th, addr); 187 tmp[0] = read_reg(th, addr + 1); 188 189 res = tmp[1] + (tmp[0] << 8); 190 /* "a value of 0xffff means that the fan has stopped" */ 191 return (res == 0xffff ? 0 : (90000*60)/res); 192 } 193 194 static void write_both_fan_speed(struct thermostat *th, int speed) 195 { 196 write_fan_speed(th, speed, 0); 197 if (therm_type == ADT7460) 198 write_fan_speed(th, speed, 1); 199 } 200 201 static void write_fan_speed(struct thermostat *th, int speed, int fan) 202 { 203 u8 manual; 204 205 if (speed > 0xff) 206 speed = 0xff; 207 else if (speed < -1) 208 speed = 0; 209 210 if (therm_type == ADT7467 && fan == 1) 211 return; 212 213 if (th->last_speed[fan] != speed) { 214 if (speed == -1) 215 printk(KERN_DEBUG "adt746x: Setting speed to automatic " 216 "for %s fan.\n", fan?"GPU":"CPU"); 217 else 218 printk(KERN_DEBUG "adt746x: Setting speed to %d " 219 "for %s fan.\n", speed, fan?"GPU":"CPU"); 220 } else 221 return; 222 223 if (speed >= 0) { 224 manual = read_reg(th, MANUAL_MODE[fan]); 225 write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK); 226 write_reg(th, FAN_SPD_SET[fan], speed); 227 } else { 228 /* back to automatic */ 229 if(therm_type == ADT7460) { 230 manual = read_reg(th, 231 MANUAL_MODE[fan]) & (~MANUAL_MASK); 232 233 write_reg(th, 234 MANUAL_MODE[fan], manual|REM_CONTROL[fan]); 235 } else { 236 manual = read_reg(th, MANUAL_MODE[fan]); 237 write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK)); 238 } 239 } 240 241 th->last_speed[fan] = speed; 242 } 243 244 static void read_sensors(struct thermostat *th) 245 { 246 int i = 0; 247 248 for (i = 0; i < 3; i++) 249 th->temps[i] = read_reg(th, TEMP_REG[i]); 250 } 251 252 #ifdef DEBUG 253 static void display_stats(struct thermostat *th) 254 { 255 if (th->temps[0] != th->cached_temp[0] 256 || th->temps[1] != th->cached_temp[1] 257 || th->temps[2] != th->cached_temp[2]) { 258 printk(KERN_INFO "adt746x: Temperature infos:" 259 " thermostats: %d,%d,%d;" 260 " limits: %d,%d,%d;" 261 " fan speed: %d RPM\n", 262 th->temps[0], th->temps[1], th->temps[2], 263 th->limits[0], th->limits[1], th->limits[2], 264 read_fan_speed(th, FAN_SPEED[0])); 265 } 266 th->cached_temp[0] = th->temps[0]; 267 th->cached_temp[1] = th->temps[1]; 268 th->cached_temp[2] = th->temps[2]; 269 } 270 #endif 271 272 static void update_fans_speed (struct thermostat *th) 273 { 274 int lastvar = 0; /* last variation, for iBook */ 275 int i = 0; 276 277 /* we don't care about local sensor, so we start at sensor 1 */ 278 for (i = 1; i < 3; i++) { 279 int started = 0; 280 int fan_number = (therm_type == ADT7460 && i == 2); 281 int var = th->temps[i] - th->limits[i]; 282 283 if (var > -1) { 284 int step = (255 - fan_speed) / 7; 285 int new_speed = 0; 286 287 /* hysteresis : change fan speed only if variation is 288 * more than two degrees */ 289 if (abs(var - th->last_var[fan_number]) < 2) 290 continue; 291 292 started = 1; 293 new_speed = fan_speed + ((var-1)*step); 294 295 if (new_speed < fan_speed) 296 new_speed = fan_speed; 297 if (new_speed > 255) 298 new_speed = 255; 299 300 printk(KERN_DEBUG "adt746x: setting fans speed to %d " 301 "(limit exceeded by %d on %s) \n", 302 new_speed, var, 303 fan_number?"GPU/pwr":"CPU"); 304 write_both_fan_speed(th, new_speed); 305 th->last_var[fan_number] = var; 306 } else if (var < -2) { 307 /* don't stop fan if GPU/power is cold and CPU is not 308 * so cold (lastvar >= -1) */ 309 if (i == 2 && lastvar < -1) { 310 if (th->last_speed[fan_number] != 0) 311 printk(KERN_DEBUG "adt746x: Stopping " 312 "fans.\n"); 313 write_both_fan_speed(th, 0); 314 } 315 } 316 317 lastvar = var; 318 319 if (started) 320 return; /* we don't want to re-stop the fan 321 * if CPU is heating and GPU/power is not */ 322 } 323 } 324 325 static int monitor_task(void *arg) 326 { 327 struct thermostat* th = arg; 328 329 while(!kthread_should_stop()) { 330 if (current->flags & PF_FREEZE) 331 refrigerator(PF_FREEZE); 332 333 msleep_interruptible(2000); 334 335 #ifndef DEBUG 336 if (fan_speed != -1) 337 read_sensors(th); 338 #else 339 read_sensors(th); 340 #endif 341 342 if (fan_speed != -1) 343 update_fans_speed(th); 344 345 #ifdef DEBUG 346 display_stats(th); 347 #endif 348 349 } 350 351 return 0; 352 } 353 354 static void set_limit(struct thermostat *th, int i) 355 { 356 /* Set CPU limit higher to avoid powerdowns */ 357 th->limits[i] = default_limits_chip[i] + limit_adjust; 358 write_reg(th, LIMIT_REG[i], th->limits[i]); 359 360 /* set our limits to normal */ 361 th->limits[i] = default_limits_local[i] + limit_adjust; 362 } 363 364 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr, 365 int busno) 366 { 367 struct thermostat* th; 368 int rc; 369 int i; 370 371 if (thermostat) 372 return 0; 373 374 th = (struct thermostat *) 375 kmalloc(sizeof(struct thermostat), GFP_KERNEL); 376 377 if (!th) 378 return -ENOMEM; 379 380 memset(th, 0, sizeof(*th)); 381 th->clt.addr = addr; 382 th->clt.adapter = adapter; 383 th->clt.driver = &thermostat_driver; 384 strcpy(th->clt.name, "thermostat"); 385 386 rc = read_reg(th, 0); 387 if (rc < 0) { 388 printk(KERN_ERR "adt746x: Thermostat failed to read config " 389 "from bus %d !\n", 390 busno); 391 kfree(th); 392 return -ENODEV; 393 } 394 395 /* force manual control to start the fan quieter */ 396 if (fan_speed == -1) 397 fan_speed = 64; 398 399 if(therm_type == ADT7460) { 400 printk(KERN_INFO "adt746x: ADT7460 initializing\n"); 401 /* The 7460 needs to be started explicitly */ 402 write_reg(th, CONFIG_REG, 1); 403 } else 404 printk(KERN_INFO "adt746x: ADT7467 initializing\n"); 405 406 for (i = 0; i < 3; i++) { 407 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]); 408 set_limit(th, i); 409 } 410 411 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d" 412 " to %d, %d, %d\n", 413 th->initial_limits[0], th->initial_limits[1], 414 th->initial_limits[2], th->limits[0], th->limits[1], 415 th->limits[2]); 416 417 thermostat = th; 418 419 if (i2c_attach_client(&th->clt)) { 420 printk(KERN_INFO "adt746x: Thermostat failed to attach " 421 "client !\n"); 422 thermostat = NULL; 423 kfree(th); 424 return -ENODEV; 425 } 426 427 /* be sure to really write fan speed the first time */ 428 th->last_speed[0] = -2; 429 th->last_speed[1] = -2; 430 th->last_var[0] = -80; 431 th->last_var[1] = -80; 432 433 if (fan_speed != -1) { 434 /* manual mode, stop fans */ 435 write_both_fan_speed(th, 0); 436 } else { 437 /* automatic mode */ 438 write_both_fan_speed(th, -1); 439 } 440 441 thread_therm = kthread_run(monitor_task, th, "kfand"); 442 443 if (thread_therm == ERR_PTR(-ENOMEM)) { 444 printk(KERN_INFO "adt746x: Kthread creation failed\n"); 445 thread_therm = NULL; 446 return -ENOMEM; 447 } 448 449 return 0; 450 } 451 452 /* 453 * Now, unfortunately, sysfs doesn't give us a nice void * we could 454 * pass around to the attribute functions, so we don't really have 455 * choice but implement a bunch of them... 456 * 457 */ 458 #define BUILD_SHOW_FUNC_INT(name, data) \ 459 static ssize_t show_##name(struct device *dev, char *buf) \ 460 { \ 461 return sprintf(buf, "%d\n", data); \ 462 } 463 464 #define BUILD_SHOW_FUNC_FAN(name, data) \ 465 static ssize_t show_##name(struct device *dev, char *buf) \ 466 { \ 467 return sprintf(buf, "%d (%d rpm)\n", \ 468 thermostat->last_speed[data], \ 469 read_fan_speed(thermostat, FAN_SPEED[data]) \ 470 ); \ 471 } 472 473 #define BUILD_STORE_FUNC_DEG(name, data) \ 474 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \ 475 { \ 476 int val; \ 477 int i; \ 478 val = simple_strtol(buf, NULL, 10); \ 479 printk(KERN_INFO "Adjusting limits by %d�C\n", val); \ 480 limit_adjust = val; \ 481 for (i=0; i < 3; i++) \ 482 set_limit(thermostat, i); \ 483 return n; \ 484 } 485 486 #define BUILD_STORE_FUNC_INT(name, data) \ 487 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \ 488 { \ 489 u32 val; \ 490 val = simple_strtoul(buf, NULL, 10); \ 491 if (val < 0 || val > 255) \ 492 return -EINVAL; \ 493 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \ 494 data = val; \ 495 return n; \ 496 } 497 498 BUILD_SHOW_FUNC_INT(cpu_temperature, (read_reg(thermostat, TEMP_REG[1]))) 499 BUILD_SHOW_FUNC_INT(gpu_temperature, (read_reg(thermostat, TEMP_REG[2]))) 500 BUILD_SHOW_FUNC_INT(cpu_limit, thermostat->limits[1]) 501 BUILD_SHOW_FUNC_INT(gpu_limit, thermostat->limits[2]) 502 503 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed) 504 BUILD_SHOW_FUNC_FAN(cpu_fan_speed, 0) 505 BUILD_SHOW_FUNC_FAN(gpu_fan_speed, 1) 506 507 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed) 508 BUILD_SHOW_FUNC_INT(limit_adjust, limit_adjust) 509 BUILD_STORE_FUNC_DEG(limit_adjust, thermostat) 510 511 static DEVICE_ATTR(cpu_temperature, S_IRUGO, 512 show_cpu_temperature,NULL); 513 static DEVICE_ATTR(gpu_temperature, S_IRUGO, 514 show_gpu_temperature,NULL); 515 static DEVICE_ATTR(cpu_limit, S_IRUGO, 516 show_cpu_limit, NULL); 517 static DEVICE_ATTR(gpu_limit, S_IRUGO, 518 show_gpu_limit, NULL); 519 520 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH, 521 show_specified_fan_speed,store_specified_fan_speed); 522 523 static DEVICE_ATTR(cpu_fan_speed, S_IRUGO, 524 show_cpu_fan_speed, NULL); 525 static DEVICE_ATTR(gpu_fan_speed, S_IRUGO, 526 show_gpu_fan_speed, NULL); 527 528 static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH, 529 show_limit_adjust, store_limit_adjust); 530 531 532 static int __init 533 thermostat_init(void) 534 { 535 struct device_node* np; 536 u32 *prop; 537 538 np = of_find_node_by_name(NULL, "fan"); 539 if (!np) 540 return -ENODEV; 541 if (device_is_compatible(np, "adt7460")) 542 therm_type = ADT7460; 543 else if (device_is_compatible(np, "adt7467")) 544 therm_type = ADT7467; 545 else 546 return -ENODEV; 547 548 prop = (u32 *)get_property(np, "reg", NULL); 549 if (!prop) 550 return -ENODEV; 551 552 /* look for bus either by path or using "reg" */ 553 if (strstr(np->full_name, "/i2c-bus@") != NULL) { 554 const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9); 555 therm_bus = tmp_bus[0]-'0'; 556 } else { 557 therm_bus = ((*prop) >> 8) & 0x0f; 558 } 559 560 therm_address = ((*prop) & 0xff) >> 1; 561 562 printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, " 563 "limit_adjust: %d, fan_speed: %d\n", 564 therm_bus, therm_address, limit_adjust, fan_speed); 565 566 of_dev = of_platform_device_create(np, "temperatures"); 567 568 if (of_dev == NULL) { 569 printk(KERN_ERR "Can't register temperatures device !\n"); 570 return -ENODEV; 571 } 572 573 device_create_file(&of_dev->dev, &dev_attr_cpu_temperature); 574 device_create_file(&of_dev->dev, &dev_attr_gpu_temperature); 575 device_create_file(&of_dev->dev, &dev_attr_cpu_limit); 576 device_create_file(&of_dev->dev, &dev_attr_gpu_limit); 577 device_create_file(&of_dev->dev, &dev_attr_limit_adjust); 578 device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed); 579 device_create_file(&of_dev->dev, &dev_attr_cpu_fan_speed); 580 if(therm_type == ADT7460) 581 device_create_file(&of_dev->dev, &dev_attr_gpu_fan_speed); 582 583 #ifndef CONFIG_I2C_KEYWEST 584 request_module("i2c-keywest"); 585 #endif 586 587 return i2c_add_driver(&thermostat_driver); 588 } 589 590 static void __exit 591 thermostat_exit(void) 592 { 593 if (of_dev) { 594 device_remove_file(&of_dev->dev, &dev_attr_cpu_temperature); 595 device_remove_file(&of_dev->dev, &dev_attr_gpu_temperature); 596 device_remove_file(&of_dev->dev, &dev_attr_cpu_limit); 597 device_remove_file(&of_dev->dev, &dev_attr_gpu_limit); 598 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust); 599 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed); 600 device_remove_file(&of_dev->dev, &dev_attr_cpu_fan_speed); 601 602 if(therm_type == ADT7460) 603 device_remove_file(&of_dev->dev, 604 &dev_attr_gpu_fan_speed); 605 606 of_device_unregister(of_dev); 607 } 608 i2c_del_driver(&thermostat_driver); 609 } 610 611 module_init(thermostat_init); 612 module_exit(thermostat_exit); 613