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 #include <linux/kthread.h>
  32
  33 #undef DEBUG
  34
  35 #define CONFIG_REG   0x40
  36 #define MANUAL_MASK  0xe0
  37 #define AUTO_MASK    0x20
  38
  39 static u8 TEMP_REG[3]    = {0x26, 0x25, 0x27}; /* local, cpu, gpu */
  40 static u8 LIMIT_REG[3]   = {0x6b, 0x6a, 0x6c}; /* local, cpu, gpu */
  41 static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
  42 static u8 REM_CONTROL[2] = {0x00, 0x40};
  43 static u8 FAN_SPEED[2]   = {0x28, 0x2a};
  44 static u8 FAN_SPD_SET[2] = {0x30, 0x31};
  45
  46 static u8 default_limits_local[3] = {70, 50, 70};    /* local, cpu, gpu */
  47 static u8 default_limits_chip[3] = {80, 65, 80};    /* local, cpu, gpu */
  48
  49 static int limit_adjust = 0;
  50 static int fan_speed = -1;
  51
  52 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
  53 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and Powerbook G4 Alu");
  54 MODULE_LICENSE("GPL");
  55
  56 MODULE_PARM(limit_adjust,"i");
  57 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 cpu, 70 gpu) by N degrees.");
  58 MODULE_PARM(fan_speed,"i");
  59 MODULE_PARM_DESC(fan_speed,"Specify fan speed (0-255) when lim < temp < lim+8 (default 128)");
  60
  61 struct thermostat {
  62         struct i2c_client       clt;
  63         u8                      cached_temp[3];
  64         u8                      initial_limits[3];
  65         u8                      limits[3];
  66         int                     last_speed[2];
  67         int                     overriding[2];
  68 };
  69
  70 static enum {ADT7460, ADT7467} therm_type;
  71 static int therm_bus, therm_address;
  72 static struct of_device * of_dev;
  73 static struct thermostat* thermostat;
  74 static struct task_struct *thread_therm = NULL;
  75
  76 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr, int busno);
  77 static void write_both_fan_speed(struct thermostat *th, int speed);
  78 static void write_fan_speed(struct thermostat *th, int speed, int fan);
  79
  80 static int
  81 write_reg(struct thermostat* th, int reg, u8 data)
  82 {
  83         u8 tmp[2];
  84         int rc;
  85
  86         tmp[0] = reg;
  87         tmp[1] = data;
  88         rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
  89         if (rc < 0)
  90                 return rc;
  91         if (rc != 2)
  92                 return -ENODEV;
  93         return 0;
  94 }
  95
  96 static int
  97 read_reg(struct thermostat* th, int reg)
  98 {
  99         u8 reg_addr, data;
 100         int rc;
 101
 102         reg_addr = (u8)reg;
 103         rc = i2c_master_send(&th->clt, &reg_addr, 1);
 104         if (rc < 0)
 105                 return rc;
 106         if (rc != 1)
 107                 return -ENODEV;
 108         rc = i2c_master_recv(&th->clt, (char *)&data, 1);
 109         if (rc < 0)
 110                 return rc;
 111         return data;
 112 }
 113
 114 static int
 115 attach_thermostat(struct i2c_adapter *adapter)
 116 {
 117         unsigned long bus_no;
 118
 119         if (strncmp(adapter->name, "uni-n", 5))
 120                 return -ENODEV;
 121         bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
 122         if (bus_no != therm_bus)
 123                 return -ENODEV;
 124         return attach_one_thermostat(adapter, therm_address, bus_no);
 125 }
 126
 127 static int
 128 detach_thermostat(struct i2c_adapter *adapter)
 129 {
 130         struct thermostat* th;
 131         int i;
 132
 133         if (thermostat == NULL)
 134                 return 0;
 135
 136         th = thermostat;
 137
 138         if (thread_therm != NULL) {
 139                 kthread_stop(thread_therm);
 140         }
 141
 142         printk(KERN_INFO "adt746x: Putting max temperatures back from %d, %d, %d,"
 143                 " to %d, %d, %d\n",
 144                 th->limits[0], th->limits[1], th->limits[2],
 145                 th->initial_limits[0], th->initial_limits[1], th->initial_limits[2]);
 146
 147         for (i = 0; i < 3; i++)
 148                 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
 149
 150         write_both_fan_speed(th, -1);
 151
 152         i2c_detach_client(&th->clt);
 153
 154         thermostat = NULL;
 155
 156         kfree(th);
 157
 158         return 0;
 159 }
 160
 161 static struct i2c_driver thermostat_driver = {
 162         .name           ="Apple Thermostat ADT746x",
 163         .id             =0xDEAD7467,
 164         .flags          =I2C_DF_NOTIFY,
 165         .attach_adapter =&attach_thermostat,
 166         .detach_adapter =&detach_thermostat,
 167 };
 168
 169 static int read_fan_speed(struct thermostat *th, u8 addr)
 170 {
 171         u8 tmp[2];
 172         u16 res;
 173
 174         /* should start with low byte */
 175         tmp[1] = read_reg(th, addr);
 176         tmp[0] = read_reg(th, addr + 1);
 177
 178         res = tmp[1] + (tmp[0] << 8);
 179         /* "a value of 0xffff means that the fan has stopped" */
 180         return (res == 0xffff ? 0 : (90000*60)/res);
 181 }
 182
 183 static void write_both_fan_speed(struct thermostat *th, int speed)
 184 {
 185         write_fan_speed(th, speed, 0);
 186         if (therm_type == ADT7460)
 187                 write_fan_speed(th, speed, 1);
 188 }
 189
 190 static void write_fan_speed(struct thermostat *th, int speed, int fan)
 191 {
 192         u8 manual;
 193
 194         if (speed > 0xff)
 195                 speed = 0xff;
 196         else if (speed < -1)
 197                 speed = 0;
 198
 199         if (therm_type == ADT7467 && fan == 1)
 200                 return;
 201
 202         if (th->last_speed[fan] != speed) {
 203                 if (speed == -1)
 204                         printk(KERN_INFO "adt746x: Setting speed to: automatic for %s fan.\n",
 205                                 fan?"GPU":"CPU");
 206                 else
 207                         printk(KERN_INFO "adt746x: Setting speed to: %d for %s fan.\n",
 208                                 speed, fan?"GPU":"CPU");
 209         } else
 210                 return;
 211
 212         if (speed >= 0) {
 213                 manual = read_reg(th, MANUAL_MODE[fan]);
 214                 write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
 215                 write_reg(th, FAN_SPD_SET[fan], speed);
 216         } else {
 217                 /* back to automatic */
 218                 if(therm_type == ADT7460) {
 219                         manual = read_reg(th, MANUAL_MODE[fan]) & (~MANUAL_MASK);
 220                         write_reg(th, MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
 221                 } else {
 222                         manual = read_reg(th, MANUAL_MODE[fan]);
 223                         write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
 224                 }
 225         }
 226
 227         th->last_speed[fan] = speed;
 228 }
 229
 230 static int monitor_task(void *arg)
 231 {
 232         struct thermostat* th = arg;
 233         u8 temps[3];
 234         u8 lims[3];
 235         int i;
 236 #ifdef DEBUG
 237         int mfan_speed;
 238 #endif
 239         while(!kthread_should_stop())
 240         {
 241                 msleep_interruptible(2000);
 242
 243                 /* Check status */
 244                 /* local   : chip */
 245                 /* remote 1: CPU ?*/
 246                 /* remote 2: GPU ?*/
 247 #ifndef DEBUG
 248                 if (fan_speed != -1) {
 249 #endif
 250                         for (i = 0; i < 3; i++) {
 251                                 temps[i]  = read_reg(th, TEMP_REG[i]);
 252                                 lims[i]   = th->limits[i];
 253                         }
 254 #ifndef DEBUG
 255                 }
 256 #endif
 257                 if (fan_speed != -1) {
 258                         int lastvar = 0;                /* for iBook */
 259                         for (i = 1; i < 3; i++) {       /* we don't care about local sensor */
 260                                 int started = 0;
 261                                 int fan_number = (therm_type == ADT7460 && i == 2);
 262                                 int var = temps[i] - lims[i];
 263                                 if (var > 8) {
 264                                         if (th->overriding[fan_number] == 0)
 265                                                 printk(KERN_INFO "adt746x: Limit exceeded by %d, overriding specified fan speed for %s.\n",
 266                                                         var, fan_number?"GPU":"CPU");
 267                                         th->overriding[fan_number] = 1;
 268                                         write_fan_speed(th, 255, fan_number);
 269                                         started = 1;
 270                                 } else if ((!th->overriding[fan_number] || var < 6) && var > 0) {
 271                                         if (th->overriding[fan_number] == 1)
 272                                                 printk(KERN_INFO "adt746x: Limit exceeded by %d, setting speed to specified for %s.\n",
 273                                                         var, fan_number?"GPU":"CPU");
 274                                         th->overriding[fan_number] = 0;
 275                                         write_fan_speed(th, fan_speed, fan_number);
 276                                         started = 1;
 277                                 } else if (var < -1) {
 278                                         /* don't stop iBook fan if GPU is cold and CPU is not
 279                                          * so cold (lastvar >= -1) */
 280                                         if (therm_type == ADT7460 || lastvar < -1 || i == 1) {
 281                                                 if (th->last_speed[fan_number] != 0)
 282                                                         printk(KERN_INFO "adt746x: Stopping %s fan.\n",
 283                                                                 fan_number?"GPU":"CPU");
 284                                                 write_fan_speed(th, 0, fan_number);
 285                                         }
 286                                 }
 287
 288                                 lastvar = var;
 289
 290                                 if (started && therm_type == ADT7467)
 291                                         break; /* we don't want to re-stop the fan
 292                                                 * if CPU is heating and GPU is not */
 293                         }
 294                 }
 295 #ifdef DEBUG
 296                 mfan_speed = read_fan_speed(th, FAN_SPEED[0]);
 297                 /* only one fan in the iBook G4 */
 298
 299                 if (temps[0] != th->cached_temp[0]
 300                 ||  temps[1] != th->cached_temp[1]
 301                 ||  temps[2] != th->cached_temp[2]) {
 302                         printk(KERN_INFO "adt746x: Temperature infos:"
 303                                          " thermostats: %d,%d,%d;"
 304                                          " limits: %d,%d,%d;"
 305                                          " fan speed: %d RPM\n",
 306                                 temps[0], temps[1], temps[2],
 307                                 lims[0],  lims[1],  lims[2],
 308                                 mfan_speed);
 309                 }
 310                 th->cached_temp[0] = temps[0];
 311                 th->cached_temp[1] = temps[1];
 312                 th->cached_temp[2] = temps[2];
 313 #endif
 314         }
 315
 316         return 0;
 317 }
 318
 319 static void
 320 set_limit(struct thermostat *th, int i)
 321 {
 322                 /* Set CPU limit higher to avoid powerdowns */
 323                 th->limits[i] = default_limits_chip[i] + limit_adjust;
 324                 write_reg(th, LIMIT_REG[i], th->limits[i]);
 325
 326                 /* set our limits to normal */
 327                 th->limits[i] = default_limits_local[i] + limit_adjust;
 328 }
 329
 330 static int
 331 attach_one_thermostat(struct i2c_adapter *adapter, int addr, int busno)
 332 {
 333         struct thermostat* th;
 334         int rc;
 335         int i;
 336
 337         if (thermostat)
 338                 return 0;
 339         th = (struct thermostat *)kmalloc(sizeof(struct thermostat), GFP_KERNEL);
 340         if (!th)
 341                 return -ENOMEM;
 342         memset(th, 0, sizeof(*th));
 343         th->clt.addr = addr;
 344         th->clt.adapter = adapter;
 345         th->clt.driver = &thermostat_driver;
 346         th->clt.id = 0xDEAD7467;
 347         strcpy(th->clt.name, "thermostat");
 348
 349         rc = read_reg(th, 0);
 350         if (rc < 0) {
 351                 printk(KERN_ERR "adt746x: Thermostat failed to read config from bus %d !\n",
 352                         busno);
 353                 kfree(th);
 354                 return -ENODEV;
 355         }
 356         /* force manual control to start the fan quieter */
 357
 358         if (fan_speed == -1)
 359                 fan_speed=128;
 360
 361         if(therm_type == ADT7460) {
 362                 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
 363                 /* The 7460 needs to be started explicitly */
 364                 write_reg(th, CONFIG_REG, 1);
 365         } else
 366                 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
 367
 368         for (i = 0; i < 3; i++) {
 369                 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
 370                 set_limit(th, i);
 371         }
 372
 373         printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
 374                 " to %d, %d, %d\n",
 375                 th->initial_limits[0], th->initial_limits[1], th->initial_limits[2],
 376                 th->limits[0], th->limits[1], th->limits[2]);
 377
 378         thermostat = th;
 379
 380         if (i2c_attach_client(&th->clt)) {
 381                 printk(KERN_INFO "adt746x: Thermostat failed to attach client !\n");
 382                 thermostat = NULL;
 383                 kfree(th);
 384                 return -ENODEV;
 385         }
 386
 387         /* be sure to really write fan speed the first time */
 388         th->last_speed[0] = -2;
 389         th->last_speed[1] = -2;
 390
 391         if (fan_speed != -1) {
 392                 write_both_fan_speed(th, 0);
 393         } else {
 394                 write_both_fan_speed(th, -1);
 395         }
 396
 397         thread_therm = kthread_run(monitor_task, th, "kfand");
 398
 399         if (thread_therm == ERR_PTR(-ENOMEM)) {
 400                 printk(KERN_INFO "adt746x: Kthread creation failed\n");
 401                 thread_therm = NULL;
 402                 return -ENOMEM;
 403         }
 404
 405         return 0;
 406 }
 407
 408 /*
 409  * Now, unfortunately, sysfs doesn't give us a nice void * we could
 410  * pass around to the attribute functions, so we don't really have
 411  * choice but implement a bunch of them...
 412  *
 413  */
 414 #define BUILD_SHOW_FUNC_INT(name, data)                         \
 415 static ssize_t show_##name(struct device *dev, char *buf)       \
 416 {                                                               \
 417         return sprintf(buf, "%d\n", data);                      \
 418 }
 419
 420 #define BUILD_SHOW_FUNC_FAN(name, data)                         \
 421 static ssize_t show_##name(struct device *dev, char *buf)       \
 422 {                                                               \
 423         return sprintf(buf, "%d (%d rpm)\n",                    \
 424                 thermostat->last_speed[data],                   \
 425                 read_fan_speed(thermostat, FAN_SPEED[data])     \
 426                 );                                              \
 427 }
 428
 429 #define BUILD_STORE_FUNC_DEG(name, data)                        \
 430 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \
 431 {                                                               \
 432         int val;                                                \
 433         int i;                                                  \
 434         val = simple_strtol(buf, NULL, 10);                     \
 435         printk(KERN_INFO "Adjusting limits by %d°C\n", val);    \
 436         limit_adjust = val;                                     \
 437         for (i=0; i < 3; i++)                                   \
 438                 set_limit(thermostat, i);                       \
 439         return n;                                               \
 440 }
 441
 442 #define BUILD_STORE_FUNC_INT(name, data)                        \
 443 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \
 444 {                                                               \
 445         u32 val;                                                \
 446         val = simple_strtoul(buf, NULL, 10);                    \
 447         if (val < 0 || val > 255)                               \
 448                 return -EINVAL;                                 \
 449         printk(KERN_INFO "Setting specified fan speed to %d\n", val);   \
 450         data = val;                                             \
 451         return n;                                               \
 452 }
 453
 454 BUILD_SHOW_FUNC_INT(cpu_temperature,     (read_reg(thermostat, TEMP_REG[1])))
 455 BUILD_SHOW_FUNC_INT(gpu_temperature,     (read_reg(thermostat, TEMP_REG[2])))
 456 BUILD_SHOW_FUNC_INT(cpu_limit,           thermostat->limits[1])
 457 BUILD_SHOW_FUNC_INT(gpu_limit,           thermostat->limits[2])
 458
 459 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
 460 BUILD_SHOW_FUNC_FAN(cpu_fan_speed,       0)
 461 BUILD_SHOW_FUNC_FAN(gpu_fan_speed,       1)
 462
 463 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
 464 BUILD_SHOW_FUNC_INT(limit_adjust,        limit_adjust)
 465 BUILD_STORE_FUNC_DEG(limit_adjust,       thermostat)
 466
 467 static DEVICE_ATTR(cpu_temperature,     S_IRUGO,
 468                    show_cpu_temperature,NULL);
 469 static DEVICE_ATTR(gpu_temperature,     S_IRUGO,
 470                    show_gpu_temperature,NULL);
 471 static DEVICE_ATTR(cpu_limit,           S_IRUGO,
 472                    show_cpu_limit,      NULL);
 473 static DEVICE_ATTR(gpu_limit,           S_IRUGO,
 474                    show_gpu_limit,      NULL);
 475
 476 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
 477                    show_specified_fan_speed,store_specified_fan_speed);
 478
 479 static DEVICE_ATTR(cpu_fan_speed,       S_IRUGO,
 480                    show_cpu_fan_speed,  NULL);
 481 static DEVICE_ATTR(gpu_fan_speed,       S_IRUGO,
 482                    show_gpu_fan_speed,  NULL);
 483
 484 static DEVICE_ATTR(limit_adjust,        S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
 485                    show_limit_adjust,   store_limit_adjust);
 486
 487
 488 static int __init
 489 thermostat_init(void)
 490 {
 491         struct device_node* np;
 492         u32 *prop;
 493
 494         np = of_find_node_by_name(NULL, "fan");
 495         if (!np)
 496                 return -ENODEV;
 497         if (device_is_compatible(np, "adt7460"))
 498                 therm_type = ADT7460;
 499         else if (device_is_compatible(np, "adt7467"))
 500                 therm_type = ADT7467;
 501         else
 502                 return -ENODEV;
 503
 504         prop = (u32 *)get_property(np, "reg", NULL);
 505         if (!prop)
 506                 return -ENODEV;
 507         therm_bus = ((*prop) >> 8) & 0x0f;
 508         therm_address = ((*prop) & 0xff) >> 1;
 509
 510         printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, limit_adjust: %d, fan_speed: %d\n",
 511                 therm_bus, therm_address, limit_adjust, fan_speed);
 512
 513         of_dev = of_platform_device_create(np, "temperatures");
 514
 515         if (of_dev == NULL) {
 516                 printk(KERN_ERR "Can't register temperatures device !\n");
 517                 return -ENODEV;
 518         }
 519
 520         device_create_file(&of_dev->dev, &dev_attr_cpu_temperature);
 521         device_create_file(&of_dev->dev, &dev_attr_gpu_temperature);
 522         device_create_file(&of_dev->dev, &dev_attr_cpu_limit);
 523         device_create_file(&of_dev->dev, &dev_attr_gpu_limit);
 524         device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
 525         device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
 526         device_create_file(&of_dev->dev, &dev_attr_cpu_fan_speed);
 527         if(therm_type == ADT7460)
 528                 device_create_file(&of_dev->dev, &dev_attr_gpu_fan_speed);
 529
 530 #ifndef CONFIG_I2C_KEYWEST
 531         request_module("i2c-keywest");
 532 #endif
 533
 534         return i2c_add_driver(&thermostat_driver);
 535 }
 536
 537 static void __exit
 538 thermostat_exit(void)
 539 {
 540         if (of_dev) {
 541                 device_remove_file(&of_dev->dev, &dev_attr_cpu_temperature);
 542                 device_remove_file(&of_dev->dev, &dev_attr_gpu_temperature);
 543                 device_remove_file(&of_dev->dev, &dev_attr_cpu_limit);
 544                 device_remove_file(&of_dev->dev, &dev_attr_gpu_limit);
 545                 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
 546                 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
 547                 device_remove_file(&of_dev->dev, &dev_attr_cpu_fan_speed);
 548                 if(therm_type == ADT7460)
 549                         device_remove_file(&of_dev->dev, &dev_attr_gpu_fan_speed);
 550                 of_device_unregister(of_dev);
 551         }
 552         i2c_del_driver(&thermostat_driver);
 553 }
 554
 555 module_init(thermostat_init);
 556 module_exit(thermostat_exit);