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 <asm/prom.h>
  26 #include <asm/machdep.h>
  27 #include <asm/io.h>
  28 #include <asm/system.h>
  29 #include <asm/sections.h>
  30 #include <asm/of_device.h>
  31
  32 #undef DEBUG
  33
  34 #define CONFIG_REG   0x40
  35 #define MANUAL_MASK  0xe0
  36 #define AUTO_MASK    0x20
  37
  38 static u8 TEMP_REG[3]    = {0x26, 0x25, 0x27}; /* local, cpu, gpu */
  39 static u8 LIMIT_REG[3]   = {0x6b, 0x6a, 0x6c}; /* local, cpu, gpu */
  40 static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
  41 static u8 REM_CONTROL[2] = {0x00, 0x40};
  42 static u8 FAN_SPEED[2]   = {0x28, 0x2a};
  43 static u8 FAN_SPD_SET[2] = {0x30, 0x31};
  44
  45 static u8 default_limits_local[3] = {70, 50, 70};    /* local, cpu, gpu */
  46 static u8 default_limits_chip[3] = {80, 65, 80};    /* local, cpu, gpu */
  47
  48 static int limit_adjust = 0;
  49 static int fan_speed = -1;
  50
  51 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
  52 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and Powerbook G4 Alu");
  53 MODULE_LICENSE("GPL");
  54
  55 MODULE_PARM(limit_adjust,"i");
  56 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50°C cpu, 70°C gpu) by N °C.");
  57 MODULE_PARM(fan_speed,"i");
  58 MODULE_PARM_DESC(fan_speed,"Specify fan speed (0-255) when lim < temp < lim+8 (default 128)");
  59
  60 struct thermostat {
  61         struct i2c_client       clt;
  62         u8                      cached_temp[3];
  63         u8                      initial_limits[3];
  64         u8                      limits[3];
  65         int                     last_speed[2];
  66         int                     overriding[2];
  67 };
  68
  69 static enum {ADT7460, ADT7467} therm_type;
  70 static int therm_bus, therm_address;
  71 static struct of_device * of_dev;
  72 static struct thermostat* thermostat;
  73 static pid_t monitor_thread_id;
  74 static int monitor_running;
  75 static struct completion monitor_task_compl;
  76
  77 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr, int busno);
  78 static void write_both_fan_speed(struct thermostat *th, int speed);
  79 static void write_fan_speed(struct thermostat *th, int speed, int fan);
  80
  81 static int
  82 write_reg(struct thermostat* th, int reg, u8 data)
  83 {
  84         u8 tmp[2];
  85         int rc;
  86
  87         tmp[0] = reg;
  88         tmp[1] = data;
  89         rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
  90         if (rc < 0)
  91                 return rc;
  92         if (rc != 2)
  93                 return -ENODEV;
  94         return 0;
  95 }
  96
  97 static int
  98 read_reg(struct thermostat* th, int reg)
  99 {
 100         u8 reg_addr, data;
 101         int rc;
 102
 103         reg_addr = (u8)reg;
 104         rc = i2c_master_send(&th->clt, &reg_addr, 1);
 105         if (rc < 0)
 106                 return rc;
 107         if (rc != 1)
 108                 return -ENODEV;
 109         rc = i2c_master_recv(&th->clt, (char *)&data, 1);
 110         if (rc < 0)
 111                 return rc;
 112         return data;
 113 }
 114
 115 static int
 116 attach_thermostat(struct i2c_adapter *adapter)
 117 {
 118         unsigned long bus_no;
 119
 120         if (strncmp(adapter->name, "uni-n", 5))
 121                 return -ENODEV;
 122         bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
 123         if (bus_no != therm_bus)
 124                 return -ENODEV;
 125         return attach_one_thermostat(adapter, therm_address, bus_no);
 126 }
 127
 128 static int
 129 detach_thermostat(struct i2c_adapter *adapter)
 130 {
 131         struct thermostat* th;
 132         int i;
 133
 134         if (thermostat == NULL)
 135                 return 0;
 136
 137         th = thermostat;
 138
 139         if (monitor_running) {
 140                 monitor_running = 0;
 141                 wait_for_completion(&monitor_task_compl);
 142         }
 143
 144         printk(KERN_INFO "adt746x: Putting max temperatures back from %d, %d, %d,"
 145                 " to %d, %d, %d, (°C)\n",
 146                 th->limits[0], th->limits[1], th->limits[2],
 147                 th->initial_limits[0], th->initial_limits[1], th->initial_limits[2]);
 148
 149         for (i = 0; i < 3; i++)
 150                 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
 151
 152         write_both_fan_speed(th, -1);
 153
 154         i2c_detach_client(&th->clt);
 155
 156         thermostat = NULL;
 157
 158         kfree(th);
 159
 160         return 0;
 161 }
 162
 163 static struct i2c_driver thermostat_driver = {
 164         .name           ="Apple Thermostat ADT746x",
 165         .id             =0xDEAD7467,
 166         .flags          =I2C_DF_NOTIFY,
 167         .attach_adapter =&attach_thermostat,
 168         .detach_adapter =&detach_thermostat,
 169 };
 170
 171 static int read_fan_speed(struct thermostat *th, u8 addr)
 172 {
 173         u8 tmp[2];
 174         u16 res;
 175
 176         /* should start with low byte */
 177         tmp[1] = read_reg(th, addr);
 178         tmp[0] = read_reg(th, addr + 1);
 179
 180         res = tmp[1] + (tmp[0] << 8);
 181         return (90000*60)/res;
 182 }
 183
 184 static void write_both_fan_speed(struct thermostat *th, int speed)
 185 {
 186         write_fan_speed(th, speed, 0);
 187         if (therm_type == ADT7460)
 188                 write_fan_speed(th, speed, 1);
 189 }
 190
 191 static void write_fan_speed(struct thermostat *th, int speed, int fan)
 192 {
 193         u8 manual;
 194
 195         if (speed > 0xff)
 196                 speed = 0xff;
 197         else if (speed < -1)
 198                 speed = 0;
 199
 200         if (therm_type == ADT7467 && fan == 1)
 201                 return;
 202
 203         if (th->last_speed[fan] != speed) {
 204                 if (speed == -1)
 205                         printk(KERN_INFO "adt746x: Setting speed to: automatic for %s fan.\n",
 206                                 fan?"GPU":"CPU");
 207                 else
 208                         printk(KERN_INFO "adt746x: Setting speed to: %d for %s fan.\n",
 209                                 speed, fan?"GPU":"CPU");
 210         } else
 211                 return;
 212
 213         if (speed >= 0) {
 214                 manual = read_reg(th, MANUAL_MODE[fan]);
 215                 write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
 216                 write_reg(th, FAN_SPD_SET[fan], speed);
 217         } else {
 218                 /* back to automatic */
 219                 if(therm_type == ADT7460) {
 220                         manual = read_reg(th, MANUAL_MODE[fan]) & (~MANUAL_MASK);
 221                         write_reg(th, MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
 222                 } else {
 223                         manual = read_reg(th, MANUAL_MODE[fan]);
 224                         write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
 225                 }
 226         }
 227
 228         th->last_speed[fan] = speed;
 229 }
 230
 231 static int monitor_task(void *arg)
 232 {
 233         struct thermostat* th = arg;
 234         u8 temps[3];
 235         u8 lims[3];
 236         int i;
 237 #ifdef DEBUG
 238         int mfan_speed;
 239 #endif
 240
 241         lock_kernel();
 242         daemonize("kfand");
 243         unlock_kernel();
 244         strcpy(current->comm, "thermostat");
 245         monitor_running = 1;
 246
 247         while(monitor_running)
 248         {
 249                 set_task_state(current, TASK_UNINTERRUPTIBLE);
 250                 schedule_timeout(2*HZ);
 251
 252                 /* Check status */
 253                 /* local   : chip */
 254                 /* remote 1: CPU ?*/
 255                 /* remote 2: GPU ?*/
 256 #ifndef DEBUG
 257                 if (fan_speed != -1) {
 258 #endif
 259                         for (i = 0; i < 3; i++) {
 260                                 temps[i]  = read_reg(th, TEMP_REG[i]);
 261                                 lims[i]   = th->limits[i];
 262                         }
 263 #ifndef DEBUG
 264                 }
 265 #endif
 266                 if (fan_speed != -1) {
 267                         int lastvar = 0;                /* for iBook */
 268                         for (i = 1; i < 3; i++) {       /* we don't care about local sensor */
 269                                 int started = 0;
 270                                 int fan_number = (therm_type == ADT7460 && i == 2);
 271                                 int var = temps[i] - lims[i];
 272                                 if (var > 8) {
 273                                         if (th->overriding[fan_number] == 0)
 274                                                 printk(KERN_INFO "adt746x: Limit exceeded by %d°C, overriding specified fan speed for %s.\n",
 275                                                         var, fan_number?"GPU":"CPU");
 276                                         th->overriding[fan_number] = 1;
 277                                         write_fan_speed(th, 255, fan_number);
 278                                         started = 1;
 279                                 } else if ((!th->overriding[fan_number] || var < 6) && var > 0) {
 280                                         if (th->overriding[fan_number] == 1)
 281                                                 printk(KERN_INFO "adt746x: Limit exceeded by %d°C, setting speed to specified for %s.\n",
 282                                                         var, fan_number?"GPU":"CPU");
 283                                         th->overriding[fan_number] = 0;
 284                                         write_fan_speed(th, fan_speed, fan_number);
 285                                         started = 1;
 286                                 } else if (var < -1) {
 287                                         /* don't stop iBook fan if GPU is cold and CPU is not
 288                                          * so cold (lastvar >= -1) */
 289                                         if (therm_type == ADT7460 || lastvar < -1 || i == 1) {
 290                                                 if (th->last_speed[fan_number] != 0)
 291                                                         printk(KERN_INFO "adt746x: Stopping %s fan.\n",
 292                                                                 fan_number?"GPU":"CPU");
 293                                                 write_fan_speed(th, 0, fan_number);
 294                                         }
 295                                 }
 296
 297                                 lastvar = var;
 298
 299                                 if (started && therm_type == ADT7467)
 300                                         break; /* we don't want to re-stop the fan
 301                                                 * if CPU is heating and GPU is not */
 302                         }
 303                 }
 304 #ifdef DEBUG
 305                 mfan_speed = read_fan_speed(th, FAN_SPEED[0]);
 306                 /* only one fan in the iBook G4 */
 307
 308                 if (temps[0] != th->cached_temp[0]
 309                 ||  temps[1] != th->cached_temp[1]
 310                 ||  temps[2] != th->cached_temp[2]) {
 311                         printk(KERN_INFO "adt746x: Temperature infos:"
 312                                          " thermostats: %d,%d,%d °C;"
 313                                          " limits: %d,%d,%d °C;"
 314                                          " fan speed: %d RPM\n",
 315                                 temps[0], temps[1], temps[2],
 316                                 lims[0],  lims[1],  lims[2],
 317                                 mfan_speed);
 318                 }
 319                 th->cached_temp[0] = temps[0];
 320                 th->cached_temp[1] = temps[1];
 321                 th->cached_temp[2] = temps[2];
 322 #endif
 323         }
 324
 325         complete_and_exit(&monitor_task_compl, 0);
 326         return 0;
 327 }
 328
 329 static void
 330 set_limit(struct thermostat *th, int i)
 331 {
 332                 /* Set CPU limit higher to avoid powerdowns */
 333                 th->limits[i] = default_limits_chip[i] + limit_adjust;
 334                 write_reg(th, LIMIT_REG[i], th->limits[i]);
 335
 336                 /* set our limits to normal */
 337                 th->limits[i] = default_limits_local[i] + limit_adjust;
 338 }
 339
 340 static int
 341 attach_one_thermostat(struct i2c_adapter *adapter, int addr, int busno)
 342 {
 343         struct thermostat* th;
 344         int rc;
 345         int i;
 346
 347         if (thermostat)
 348                 return 0;
 349         th = (struct thermostat *)kmalloc(sizeof(struct thermostat), GFP_KERNEL);
 350         if (!th)
 351                 return -ENOMEM;
 352         memset(th, 0, sizeof(*th));
 353         th->clt.addr = addr;
 354         th->clt.adapter = adapter;
 355         th->clt.driver = &thermostat_driver;
 356         th->clt.id = 0xDEAD7467;
 357         strcpy(th->clt.name, "thermostat");
 358
 359         rc = read_reg(th, 0);
 360         if (rc < 0) {
 361                 printk(KERN_ERR "adt746x: Thermostat failed to read config from bus %d !\n",
 362                         busno);
 363                 kfree(th);
 364                 return -ENODEV;
 365         }
 366         /* force manual control to start the fan quieter */
 367
 368         if (fan_speed == -1)
 369                 fan_speed=128;
 370
 371         if(therm_type == ADT7460) {
 372                 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
 373                 /* The 7460 needs to be started explicitly */
 374                 write_reg(th, CONFIG_REG, 1);
 375         } else
 376                 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
 377
 378         for (i = 0; i < 3; i++) {
 379                 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
 380                 set_limit(th, i);
 381         }
 382
 383         printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
 384                 " to %d, %d, %d (°C)\n",
 385                 th->initial_limits[0], th->initial_limits[1], th->initial_limits[2],
 386                 th->limits[0], th->limits[1], th->limits[2]);
 387
 388         thermostat = th;
 389
 390         if (i2c_attach_client(&th->clt)) {
 391                 printk("adt746x: Thermostat failed to attach client !\n");
 392                 thermostat = NULL;
 393                 kfree(th);
 394                 return -ENODEV;
 395         }
 396
 397         /* be sure to really write fan speed the first time */
 398         th->last_speed[0] = -2;
 399         th->last_speed[1] = -2;
 400
 401         if (fan_speed != -1) {
 402                 write_both_fan_speed(th, 0);
 403         } else {
 404                 write_both_fan_speed(th, -1);
 405         }
 406
 407         init_completion(&monitor_task_compl);
 408
 409         monitor_thread_id = kernel_thread(monitor_task, th,
 410                 SIGCHLD | CLONE_KERNEL);
 411
 412         return 0;
 413 }
 414
 415 /*
 416  * Now, unfortunately, sysfs doesn't give us a nice void * we could
 417  * pass around to the attribute functions, so we don't really have
 418  * choice but implement a bunch of them...
 419  *
 420  */
 421 #define BUILD_SHOW_FUNC_DEG(name, data)                         \
 422 static ssize_t show_##name(struct device *dev, char *buf)       \
 423 {                                                               \
 424         return sprintf(buf, "%d°C\n", data);                    \
 425 }
 426 #define BUILD_SHOW_FUNC_INT(name, data)                         \
 427 static ssize_t show_##name(struct device *dev, char *buf)       \
 428 {                                                               \
 429         return sprintf(buf, "%d\n", data);                      \
 430 }
 431
 432 #define BUILD_STORE_FUNC_DEG(name, data)                        \
 433 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \
 434 {                                                               \
 435         int val;                                                \
 436         int i;                                                  \
 437         val = simple_strtol(buf, NULL, 10);                     \
 438         printk(KERN_INFO "Adjusting limits by %d°C\n", val);    \
 439         limit_adjust = val;                                     \
 440         for (i=0; i < 3; i++)                                   \
 441                 set_limit(thermostat, i);                       \
 442         return n;                                               \
 443 }
 444
 445 #define BUILD_STORE_FUNC_INT(name, data)                        \
 446 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \
 447 {                                                               \
 448         u32 val;                                                \
 449         val = simple_strtoul(buf, NULL, 10);                    \
 450         if (val < 0 || val > 255)                               \
 451                 return -EINVAL;                                 \
 452         printk(KERN_INFO "Setting fan speed to %d\n", val);     \
 453         data = val;                                             \
 454         return n;                                               \
 455 }
 456
 457 BUILD_SHOW_FUNC_DEG(cpu_temperature,     (read_reg(thermostat, TEMP_REG[1])))
 458 BUILD_SHOW_FUNC_DEG(gpu_temperature,     (read_reg(thermostat, TEMP_REG[2])))
 459 BUILD_SHOW_FUNC_DEG(cpu_limit,           thermostat->limits[1])
 460 BUILD_SHOW_FUNC_DEG(gpu_limit,           thermostat->limits[2])
 461
 462 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
 463 BUILD_SHOW_FUNC_INT(cpu_fan_speed,       (read_fan_speed(thermostat, FAN_SPEED[0])))
 464 BUILD_SHOW_FUNC_INT(gpu_fan_speed,       (read_fan_speed(thermostat, FAN_SPEED[1])))
 465
 466 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
 467 BUILD_SHOW_FUNC_INT(limit_adjust,        limit_adjust)
 468 BUILD_STORE_FUNC_DEG(limit_adjust,       thermostat)
 469
 470 static DEVICE_ATTR(cpu_temperature,     S_IRUGO,
 471                    show_cpu_temperature,NULL);
 472 static DEVICE_ATTR(gpu_temperature,     S_IRUGO,
 473                    show_gpu_temperature,NULL);
 474 static DEVICE_ATTR(cpu_limit,           S_IRUGO,
 475                    show_cpu_limit,      NULL);
 476 static DEVICE_ATTR(gpu_limit,           S_IRUGO,
 477                    show_gpu_limit,      NULL);
 478
 479 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
 480                    show_specified_fan_speed,store_specified_fan_speed);
 481
 482 static DEVICE_ATTR(cpu_fan_speed,       S_IRUGO,
 483                    show_cpu_fan_speed,  NULL);
 484 static DEVICE_ATTR(gpu_fan_speed,       S_IRUGO,
 485                    show_gpu_fan_speed,  NULL);
 486
 487 static DEVICE_ATTR(limit_adjust,        S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
 488                    show_limit_adjust,   store_limit_adjust);
 489
 490
 491 static int __init
 492 thermostat_init(void)
 493 {
 494         struct device_node* np;
 495         u32 *prop;
 496
 497         np = of_find_node_by_name(NULL, "fan");
 498         if (!np)
 499                 return -ENODEV;
 500         if (device_is_compatible(np, "adt7460"))
 501                 therm_type = ADT7460;
 502         else if (device_is_compatible(np, "adt7467"))
 503                 therm_type = ADT7467;
 504         else
 505                 return -ENODEV;
 506
 507         prop = (u32 *)get_property(np, "reg", NULL);
 508         if (!prop)
 509                 return -ENODEV;
 510         therm_bus = ((*prop) >> 8) & 0x0f;
 511         therm_address = ((*prop) & 0xff) >> 1;
 512
 513         printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, limit_adjust: %d, fan_speed: %d\n",
 514                 therm_bus, therm_address, limit_adjust, fan_speed);
 515
 516         of_dev = of_platform_device_create(np, "temperatures");
 517
 518         if (of_dev == NULL) {
 519                 printk(KERN_ERR "Can't register temperatures device !\n");
 520                 return -ENODEV;
 521         }
 522
 523         device_create_file(&of_dev->dev, &dev_attr_cpu_temperature);
 524         device_create_file(&of_dev->dev, &dev_attr_gpu_temperature);
 525         device_create_file(&of_dev->dev, &dev_attr_cpu_limit);
 526         device_create_file(&of_dev->dev, &dev_attr_gpu_limit);
 527         device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
 528         device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
 529         device_create_file(&of_dev->dev, &dev_attr_cpu_fan_speed);
 530         if(therm_type == ADT7460)
 531                 device_create_file(&of_dev->dev, &dev_attr_gpu_fan_speed);
 532
 533 #ifndef CONFIG_I2C_KEYWEST
 534         request_module("i2c-keywest");
 535 #endif
 536
 537         return i2c_add_driver(&thermostat_driver);
 538 }
 539
 540 static void __exit
 541 thermostat_exit(void)
 542 {
 543         if (of_dev) {
 544                 device_remove_file(&of_dev->dev, &dev_attr_cpu_temperature);
 545                 device_remove_file(&of_dev->dev, &dev_attr_gpu_temperature);
 546                 device_remove_file(&of_dev->dev, &dev_attr_cpu_limit);
 547                 device_remove_file(&of_dev->dev, &dev_attr_gpu_limit);
 548                 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
 549                 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
 550                 device_remove_file(&of_dev->dev, &dev_attr_cpu_fan_speed);
 551                 if(therm_type == ADT7460)
 552                         device_remove_file(&of_dev->dev, &dev_attr_gpu_fan_speed);
 553                 of_device_unregister(of_dev);
 554         }
 555         i2c_del_driver(&thermostat_driver);
 556 }
 557
 558 module_init(thermostat_init);
 559 module_exit(thermostat_exit);