2 * Device driver for the i2c thermostat found on the iBook G4, Albook G4
4 * Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt
7 * http://www.analog.com/UploadedFiles/Data_Sheets/115254175ADT7467_pra.pdf
8 * http://www.analog.com/UploadedFiles/Data_Sheets/3686221171167ADT7460_b.pdf
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>
26 #include <asm/machdep.h>
28 #include <asm/system.h>
29 #include <asm/sections.h>
30 #include <asm/of_device.h>
31 #include <linux/kthread.h>
35 #define CONFIG_REG 0x40
36 #define MANUAL_MASK 0xe0
37 #define AUTO_MASK 0x20
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};
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 */
49 static int limit_adjust = 0;
50 static int fan_speed = -1;
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");
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)");
62 struct i2c_client clt;
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;
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);
81 write_reg(struct thermostat* th, int reg, u8 data)
88 rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
97 read_reg(struct thermostat* th, int reg)
103 rc = i2c_master_send(&th->clt, ®_addr, 1);
108 rc = i2c_master_recv(&th->clt, (char *)&data, 1);
115 attach_thermostat(struct i2c_adapter *adapter)
117 unsigned long bus_no;
119 if (strncmp(adapter->name, "uni-n", 5))
121 bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
122 if (bus_no != therm_bus)
124 return attach_one_thermostat(adapter, therm_address, bus_no);
128 detach_thermostat(struct i2c_adapter *adapter)
130 struct thermostat* th;
133 if (thermostat == NULL)
138 if (thread_therm != NULL) {
139 kthread_stop(thread_therm);
142 printk(KERN_INFO "adt746x: Putting max temperatures back from %d, %d, %d,"
144 th->limits[0], th->limits[1], th->limits[2],
145 th->initial_limits[0], th->initial_limits[1], th->initial_limits[2]);
147 for (i = 0; i < 3; i++)
148 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
150 write_both_fan_speed(th, -1);
152 i2c_detach_client(&th->clt);
161 static struct i2c_driver thermostat_driver = {
162 .name ="Apple Thermostat ADT746x",
164 .flags =I2C_DF_NOTIFY,
165 .attach_adapter =&attach_thermostat,
166 .detach_adapter =&detach_thermostat,
169 static int read_fan_speed(struct thermostat *th, u8 addr)
174 /* should start with low byte */
175 tmp[1] = read_reg(th, addr);
176 tmp[0] = read_reg(th, addr + 1);
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);
183 static void write_both_fan_speed(struct thermostat *th, int speed)
185 write_fan_speed(th, speed, 0);
186 if (therm_type == ADT7460)
187 write_fan_speed(th, speed, 1);
190 static void write_fan_speed(struct thermostat *th, int speed, int fan)
199 if (therm_type == ADT7467 && fan == 1)
202 if (th->last_speed[fan] != speed) {
204 printk(KERN_INFO "adt746x: Setting speed to: automatic for %s fan.\n",
207 printk(KERN_INFO "adt746x: Setting speed to: %d for %s fan.\n",
208 speed, fan?"GPU":"CPU");
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);
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]);
222 manual = read_reg(th, MANUAL_MODE[fan]);
223 write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
227 th->last_speed[fan] = speed;
230 static int monitor_task(void *arg)
232 struct thermostat* th = arg;
239 while(!kthread_should_stop())
241 msleep_interruptible(2000);
248 if (fan_speed != -1) {
250 for (i = 0; i < 3; i++) {
251 temps[i] = read_reg(th, TEMP_REG[i]);
252 lims[i] = th->limits[i];
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 */
261 int fan_number = (therm_type == ADT7460 && i == 2);
262 int var = temps[i] - lims[i];
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);
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);
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);
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 */
296 mfan_speed = read_fan_speed(th, FAN_SPEED[0]);
297 /* only one fan in the iBook G4 */
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;"
305 " fan speed: %d RPM\n",
306 temps[0], temps[1], temps[2],
307 lims[0], lims[1], lims[2],
310 th->cached_temp[0] = temps[0];
311 th->cached_temp[1] = temps[1];
312 th->cached_temp[2] = temps[2];
320 set_limit(struct thermostat *th, int i)
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]);
326 /* set our limits to normal */
327 th->limits[i] = default_limits_local[i] + limit_adjust;
331 attach_one_thermostat(struct i2c_adapter *adapter, int addr, int busno)
333 struct thermostat* th;
339 th = (struct thermostat *)kmalloc(sizeof(struct thermostat), GFP_KERNEL);
342 memset(th, 0, sizeof(*th));
344 th->clt.adapter = adapter;
345 th->clt.driver = &thermostat_driver;
346 th->clt.id = 0xDEAD7467;
347 strcpy(th->clt.name, "thermostat");
349 rc = read_reg(th, 0);
351 printk(KERN_ERR "adt746x: Thermostat failed to read config from bus %d !\n",
356 /* force manual control to start the fan quieter */
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);
366 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
368 for (i = 0; i < 3; i++) {
369 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
373 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
375 th->initial_limits[0], th->initial_limits[1], th->initial_limits[2],
376 th->limits[0], th->limits[1], th->limits[2]);
380 if (i2c_attach_client(&th->clt)) {
381 printk(KERN_INFO "adt746x: Thermostat failed to attach client !\n");
387 /* be sure to really write fan speed the first time */
388 th->last_speed[0] = -2;
389 th->last_speed[1] = -2;
391 if (fan_speed != -1) {
392 write_both_fan_speed(th, 0);
394 write_both_fan_speed(th, -1);
397 thread_therm = kthread_run(monitor_task, th, "kfand");
399 if (thread_therm == ERR_PTR(-ENOMEM)) {
400 printk(KERN_INFO "adt746x: Kthread creation failed\n");
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...
414 #define BUILD_SHOW_FUNC_INT(name, data) \
415 static ssize_t show_##name(struct device *dev, char *buf) \
417 return sprintf(buf, "%d\n", data); \
420 #define BUILD_SHOW_FUNC_FAN(name, data) \
421 static ssize_t show_##name(struct device *dev, char *buf) \
423 return sprintf(buf, "%d (%d rpm)\n", \
424 thermostat->last_speed[data], \
425 read_fan_speed(thermostat, FAN_SPEED[data]) \
429 #define BUILD_STORE_FUNC_DEG(name, data) \
430 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \
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); \
442 #define BUILD_STORE_FUNC_INT(name, data) \
443 static ssize_t store_##name(struct device *dev, const char *buf, size_t n) \
446 val = simple_strtoul(buf, NULL, 10); \
447 if (val < 0 || val > 255) \
449 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
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])
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)
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)
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);
476 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
477 show_specified_fan_speed,store_specified_fan_speed);
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);
484 static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
485 show_limit_adjust, store_limit_adjust);
489 thermostat_init(void)
491 struct device_node* np;
494 np = of_find_node_by_name(NULL, "fan");
497 if (device_is_compatible(np, "adt7460"))
498 therm_type = ADT7460;
499 else if (device_is_compatible(np, "adt7467"))
500 therm_type = ADT7467;
504 prop = (u32 *)get_property(np, "reg", NULL);
507 therm_bus = ((*prop) >> 8) & 0x0f;
508 therm_address = ((*prop) & 0xff) >> 1;
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);
513 of_dev = of_platform_device_create(np, "temperatures");
515 if (of_dev == NULL) {
516 printk(KERN_ERR "Can't register temperatures device !\n");
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);
530 #ifndef CONFIG_I2C_KEYWEST
531 request_module("i2c-keywest");
534 return i2c_add_driver(&thermostat_driver);
538 thermostat_exit(void)
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);
552 i2c_del_driver(&thermostat_driver);
555 module_init(thermostat_init);
556 module_exit(thermostat_exit);