drivers/macintosh/therm_adt746x.c

   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, &reg_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);