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/types.h>
13 #include <linux/module.h>
14 #include <linux/errno.h>
15 #include <linux/kernel.h>
16 #include <linux/delay.h>
17 #include <linux/sched.h>
18 #include <linux/i2c.h>
19 #include <linux/slab.h>
20 #include <linux/init.h>
21 #include <linux/spinlock.h>
22 #include <linux/smp_lock.h>
23 #include <linux/wait.h>
24 #include <linux/suspend.h>
25 #include <linux/kthread.h>
26 #include <linux/moduleparam.h>
27 #include <linux/freezer.h>
30 #include <asm/machdep.h>
32 #include <asm/system.h>
33 #include <asm/sections.h>
34 #include <asm/of_platform.h>
38 #define CONFIG_REG 0x40
39 #define MANUAL_MASK 0xe0
40 #define AUTO_MASK 0x20
42 static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
43 static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
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};
49 static u8 default_limits_local[3] = {70, 50, 70}; /* local, sensor1, sensor2 */
50 static u8 default_limits_chip[3] = {80, 65, 80}; /* local, sensor1, sensor2 */
51 static const char *sensor_location[3] = {NULL, NULL, NULL};
53 static int limit_adjust = 0;
54 static int fan_speed = -1;
55 static int verbose = 0;
57 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
58 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
60 MODULE_LICENSE("GPL");
62 module_param(limit_adjust, int, 0644);
63 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
66 module_param(fan_speed, int, 0644);
67 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
70 module_param(verbose, bool, 0);
71 MODULE_PARM_DESC(verbose,"Verbose log operations "
75 struct i2c_client clt;
84 static enum {ADT7460, ADT7467} therm_type;
85 static int therm_bus, therm_address;
86 static struct of_device * of_dev;
87 static struct thermostat* thermostat;
88 static struct task_struct *thread_therm = NULL;
90 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
93 static void write_both_fan_speed(struct thermostat *th, int speed);
94 static void write_fan_speed(struct thermostat *th, int speed, int fan);
97 write_reg(struct thermostat* th, int reg, u8 data)
104 rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
113 read_reg(struct thermostat* th, int reg)
119 rc = i2c_master_send(&th->clt, ®_addr, 1);
124 rc = i2c_master_recv(&th->clt, (char *)&data, 1);
131 attach_thermostat(struct i2c_adapter *adapter)
133 unsigned long bus_no;
135 if (strncmp(adapter->name, "uni-n", 5))
137 bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
138 if (bus_no != therm_bus)
140 return attach_one_thermostat(adapter, therm_address, bus_no);
144 detach_thermostat(struct i2c_adapter *adapter)
146 struct thermostat* th;
149 if (thermostat == NULL)
154 if (thread_therm != NULL) {
155 kthread_stop(thread_therm);
158 printk(KERN_INFO "adt746x: Putting max temperatures back from "
159 "%d, %d, %d to %d, %d, %d\n",
160 th->limits[0], th->limits[1], th->limits[2],
161 th->initial_limits[0], th->initial_limits[1],
162 th->initial_limits[2]);
164 for (i = 0; i < 3; i++)
165 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
167 write_both_fan_speed(th, -1);
169 i2c_detach_client(&th->clt);
178 static struct i2c_driver thermostat_driver = {
180 .name = "therm_adt746x",
182 .attach_adapter = attach_thermostat,
183 .detach_adapter = detach_thermostat,
186 static int read_fan_speed(struct thermostat *th, u8 addr)
191 /* should start with low byte */
192 tmp[1] = read_reg(th, addr);
193 tmp[0] = read_reg(th, addr + 1);
195 res = tmp[1] + (tmp[0] << 8);
196 /* "a value of 0xffff means that the fan has stopped" */
197 return (res == 0xffff ? 0 : (90000*60)/res);
200 static void write_both_fan_speed(struct thermostat *th, int speed)
202 write_fan_speed(th, speed, 0);
203 if (therm_type == ADT7460)
204 write_fan_speed(th, speed, 1);
207 static void write_fan_speed(struct thermostat *th, int speed, int fan)
216 if (therm_type == ADT7467 && fan == 1)
219 if (th->last_speed[fan] != speed) {
222 printk(KERN_DEBUG "adt746x: Setting speed to automatic "
223 "for %s fan.\n", sensor_location[fan+1]);
225 printk(KERN_DEBUG "adt746x: Setting speed to %d "
226 "for %s fan.\n", speed, sensor_location[fan+1]);
232 manual = read_reg(th, MANUAL_MODE[fan]);
233 write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
234 write_reg(th, FAN_SPD_SET[fan], speed);
236 /* back to automatic */
237 if(therm_type == ADT7460) {
238 manual = read_reg(th,
239 MANUAL_MODE[fan]) & (~MANUAL_MASK);
242 MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
244 manual = read_reg(th, MANUAL_MODE[fan]);
245 write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
249 th->last_speed[fan] = speed;
252 static void read_sensors(struct thermostat *th)
256 for (i = 0; i < 3; i++)
257 th->temps[i] = read_reg(th, TEMP_REG[i]);
261 static void display_stats(struct thermostat *th)
263 if (th->temps[0] != th->cached_temp[0]
264 || th->temps[1] != th->cached_temp[1]
265 || th->temps[2] != th->cached_temp[2]) {
266 printk(KERN_INFO "adt746x: Temperature infos:"
267 " thermostats: %d,%d,%d;"
269 " fan speed: %d RPM\n",
270 th->temps[0], th->temps[1], th->temps[2],
271 th->limits[0], th->limits[1], th->limits[2],
272 read_fan_speed(th, FAN_SPEED[0]));
274 th->cached_temp[0] = th->temps[0];
275 th->cached_temp[1] = th->temps[1];
276 th->cached_temp[2] = th->temps[2];
280 static void update_fans_speed (struct thermostat *th)
282 int lastvar = 0; /* last variation, for iBook */
285 /* we don't care about local sensor, so we start at sensor 1 */
286 for (i = 1; i < 3; i++) {
288 int fan_number = (therm_type == ADT7460 && i == 2);
289 int var = th->temps[i] - th->limits[i];
292 int step = (255 - fan_speed) / 7;
295 /* hysteresis : change fan speed only if variation is
296 * more than two degrees */
297 if (abs(var - th->last_var[fan_number]) < 2)
301 new_speed = fan_speed + ((var-1)*step);
303 if (new_speed < fan_speed)
304 new_speed = fan_speed;
309 printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
310 "(limit exceeded by %d on %s) \n",
312 sensor_location[fan_number+1]);
313 write_both_fan_speed(th, new_speed);
314 th->last_var[fan_number] = var;
315 } else if (var < -2) {
316 /* don't stop fan if sensor2 is cold and sensor1 is not
317 * so cold (lastvar >= -1) */
318 if (i == 2 && lastvar < -1) {
319 if (th->last_speed[fan_number] != 0)
321 printk(KERN_DEBUG "adt746x: Stopping "
323 write_both_fan_speed(th, 0);
330 return; /* we don't want to re-stop the fan
331 * if sensor1 is heating and sensor2 is not */
335 static int monitor_task(void *arg)
337 struct thermostat* th = arg;
339 while(!kthread_should_stop()) {
341 msleep_interruptible(2000);
351 update_fans_speed(th);
362 static void set_limit(struct thermostat *th, int i)
364 /* Set sensor1 limit higher to avoid powerdowns */
365 th->limits[i] = default_limits_chip[i] + limit_adjust;
366 write_reg(th, LIMIT_REG[i], th->limits[i]);
368 /* set our limits to normal */
369 th->limits[i] = default_limits_local[i] + limit_adjust;
372 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
375 struct thermostat* th;
382 th = (struct thermostat *)
383 kmalloc(sizeof(struct thermostat), GFP_KERNEL);
388 memset(th, 0, sizeof(*th));
390 th->clt.adapter = adapter;
391 th->clt.driver = &thermostat_driver;
392 strcpy(th->clt.name, "thermostat");
394 rc = read_reg(th, 0);
396 printk(KERN_ERR "adt746x: Thermostat failed to read config "
403 /* force manual control to start the fan quieter */
407 if(therm_type == ADT7460) {
408 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
409 /* The 7460 needs to be started explicitly */
410 write_reg(th, CONFIG_REG, 1);
412 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
414 for (i = 0; i < 3; i++) {
415 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
419 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
421 th->initial_limits[0], th->initial_limits[1],
422 th->initial_limits[2], th->limits[0], th->limits[1],
427 if (i2c_attach_client(&th->clt)) {
428 printk(KERN_INFO "adt746x: Thermostat failed to attach "
435 /* be sure to really write fan speed the first time */
436 th->last_speed[0] = -2;
437 th->last_speed[1] = -2;
438 th->last_var[0] = -80;
439 th->last_var[1] = -80;
441 if (fan_speed != -1) {
442 /* manual mode, stop fans */
443 write_both_fan_speed(th, 0);
446 write_both_fan_speed(th, -1);
449 thread_therm = kthread_run(monitor_task, th, "kfand");
451 if (thread_therm == ERR_PTR(-ENOMEM)) {
452 printk(KERN_INFO "adt746x: Kthread creation failed\n");
461 * Now, unfortunately, sysfs doesn't give us a nice void * we could
462 * pass around to the attribute functions, so we don't really have
463 * choice but implement a bunch of them...
465 * FIXME, it does now...
467 #define BUILD_SHOW_FUNC_INT(name, data) \
468 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
470 return sprintf(buf, "%d\n", data); \
473 #define BUILD_SHOW_FUNC_STR(name, data) \
474 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
476 return sprintf(buf, "%s\n", data); \
479 #define BUILD_SHOW_FUNC_FAN(name, data) \
480 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
482 return sprintf(buf, "%d (%d rpm)\n", \
483 thermostat->last_speed[data], \
484 read_fan_speed(thermostat, FAN_SPEED[data]) \
488 #define BUILD_STORE_FUNC_DEG(name, data) \
489 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
493 val = simple_strtol(buf, NULL, 10); \
494 printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \
495 limit_adjust = val; \
496 for (i=0; i < 3; i++) \
497 set_limit(thermostat, i); \
501 #define BUILD_STORE_FUNC_INT(name, data) \
502 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
505 val = simple_strtoul(buf, NULL, 10); \
506 if (val < 0 || val > 255) \
508 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
513 BUILD_SHOW_FUNC_INT(sensor1_temperature, (read_reg(thermostat, TEMP_REG[1])))
514 BUILD_SHOW_FUNC_INT(sensor2_temperature, (read_reg(thermostat, TEMP_REG[2])))
515 BUILD_SHOW_FUNC_INT(sensor1_limit, thermostat->limits[1])
516 BUILD_SHOW_FUNC_INT(sensor2_limit, thermostat->limits[2])
517 BUILD_SHOW_FUNC_STR(sensor1_location, sensor_location[1])
518 BUILD_SHOW_FUNC_STR(sensor2_location, sensor_location[2])
520 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
521 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed, 0)
522 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed, 1)
524 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
525 BUILD_SHOW_FUNC_INT(limit_adjust, limit_adjust)
526 BUILD_STORE_FUNC_DEG(limit_adjust, thermostat)
528 static DEVICE_ATTR(sensor1_temperature, S_IRUGO,
529 show_sensor1_temperature,NULL);
530 static DEVICE_ATTR(sensor2_temperature, S_IRUGO,
531 show_sensor2_temperature,NULL);
532 static DEVICE_ATTR(sensor1_limit, S_IRUGO,
533 show_sensor1_limit, NULL);
534 static DEVICE_ATTR(sensor2_limit, S_IRUGO,
535 show_sensor2_limit, NULL);
536 static DEVICE_ATTR(sensor1_location, S_IRUGO,
537 show_sensor1_location, NULL);
538 static DEVICE_ATTR(sensor2_location, S_IRUGO,
539 show_sensor2_location, NULL);
541 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
542 show_specified_fan_speed,store_specified_fan_speed);
544 static DEVICE_ATTR(sensor1_fan_speed, S_IRUGO,
545 show_sensor1_fan_speed, NULL);
546 static DEVICE_ATTR(sensor2_fan_speed, S_IRUGO,
547 show_sensor2_fan_speed, NULL);
549 static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
550 show_limit_adjust, store_limit_adjust);
554 thermostat_init(void)
556 struct device_node* np;
558 int i = 0, offset = 0;
560 np = of_find_node_by_name(NULL, "fan");
563 if (device_is_compatible(np, "adt7460"))
564 therm_type = ADT7460;
565 else if (device_is_compatible(np, "adt7467"))
566 therm_type = ADT7467;
570 prop = get_property(np, "hwsensor-params-version", NULL);
571 printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
572 (*prop == 1)?"":"un");
576 prop = get_property(np, "reg", NULL);
580 /* look for bus either by path or using "reg" */
581 if (strstr(np->full_name, "/i2c-bus@") != NULL) {
582 const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9);
583 therm_bus = tmp_bus[0]-'0';
585 therm_bus = ((*prop) >> 8) & 0x0f;
588 therm_address = ((*prop) & 0xff) >> 1;
590 printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, "
591 "limit_adjust: %d, fan_speed: %d\n",
592 therm_bus, therm_address, limit_adjust, fan_speed);
594 if (get_property(np, "hwsensor-location", NULL)) {
595 for (i = 0; i < 3; i++) {
596 sensor_location[i] = get_property(np,
597 "hwsensor-location", NULL) + offset;
599 if (sensor_location[i] == NULL)
600 sensor_location[i] = "";
602 printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
603 offset += strlen(sensor_location[i]) + 1;
606 sensor_location[0] = "?";
607 sensor_location[1] = "?";
608 sensor_location[2] = "?";
611 of_dev = of_platform_device_create(np, "temperatures", NULL);
613 if (of_dev == NULL) {
614 printk(KERN_ERR "Can't register temperatures device !\n");
618 device_create_file(&of_dev->dev, &dev_attr_sensor1_temperature);
619 device_create_file(&of_dev->dev, &dev_attr_sensor2_temperature);
620 device_create_file(&of_dev->dev, &dev_attr_sensor1_limit);
621 device_create_file(&of_dev->dev, &dev_attr_sensor2_limit);
622 device_create_file(&of_dev->dev, &dev_attr_sensor1_location);
623 device_create_file(&of_dev->dev, &dev_attr_sensor2_location);
624 device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
625 device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
626 device_create_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
627 if(therm_type == ADT7460)
628 device_create_file(&of_dev->dev, &dev_attr_sensor2_fan_speed);
630 #ifndef CONFIG_I2C_POWERMAC
631 request_module("i2c-powermac");
634 return i2c_add_driver(&thermostat_driver);
638 thermostat_exit(void)
641 device_remove_file(&of_dev->dev, &dev_attr_sensor1_temperature);
642 device_remove_file(&of_dev->dev, &dev_attr_sensor2_temperature);
643 device_remove_file(&of_dev->dev, &dev_attr_sensor1_limit);
644 device_remove_file(&of_dev->dev, &dev_attr_sensor2_limit);
645 device_remove_file(&of_dev->dev, &dev_attr_sensor1_location);
646 device_remove_file(&of_dev->dev, &dev_attr_sensor2_location);
647 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
648 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
649 device_remove_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
651 if(therm_type == ADT7460)
652 device_remove_file(&of_dev->dev,
653 &dev_attr_sensor2_fan_speed);
655 of_device_unregister(of_dev);
657 i2c_del_driver(&thermostat_driver);
660 module_init(thermostat_init);
661 module_exit(thermostat_exit);