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 115254175ADT7467_pra.pdf and 3686221171167ADT7460_b.pdf
7 * http://www.onsemi.com/PowerSolutions/product.do?id=ADT7467
8 * http://www.onsemi.com/PowerSolutions/product.do?id=ADT7460
9 *
10 */
11
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/wait.h>
23 #include <linux/suspend.h>
24 #include <linux/kthread.h>
25 #include <linux/moduleparam.h>
26 #include <linux/freezer.h>
27 #include <linux/of_platform.h>
28
29 #include <asm/prom.h>
30 #include <asm/machdep.h>
31 #include <asm/io.h>
32 #include <asm/sections.h>
33
34 #undef DEBUG
35
36 #define CONFIG_REG 0x40
37 #define MANUAL_MASK 0xe0
38 #define AUTO_MASK 0x20
39 #define INVERT_MASK 0x10
40
41 static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
42 static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
43 static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
44 static u8 REM_CONTROL[2] = {0x00, 0x40};
45 static u8 FAN_SPEED[2] = {0x28, 0x2a};
46 static u8 FAN_SPD_SET[2] = {0x30, 0x31};
47
48 static u8 default_limits_local[3] = {70, 50, 70}; /* local, sensor1, sensor2 */
49 static u8 default_limits_chip[3] = {80, 65, 80}; /* local, sensor1, sensor2 */
50 static const char *sensor_location[3] = { "?", "?", "?" };
51
52 static int limit_adjust;
53 static int fan_speed = -1;
54 static bool verbose;
55
56 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
57 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
58 "Powerbook G4 Alu");
59 MODULE_LICENSE("GPL");
60
61 module_param(limit_adjust, int, 0644);
62 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
63 "by N degrees.");
64
65 module_param(fan_speed, int, 0644);
66 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
67 "(default 64)");
68
69 module_param(verbose, bool, 0);
70 MODULE_PARM_DESC(verbose,"Verbose log operations "
71 "(default 0)");
72
73 struct thermostat {
74 struct i2c_client *clt;
75 u8 temps[3];
76 u8 cached_temp[3];
77 u8 initial_limits[3];
78 u8 limits[3];
79 int last_speed[2];
80 int last_var[2];
81 int pwm_inv[2];
82 struct task_struct *thread;
83 struct platform_device *pdev;
84 enum {
85 ADT7460,
86 ADT7467
87 } type;
88 };
89
90 static void write_both_fan_speed(struct thermostat *th, int speed);
91 static void write_fan_speed(struct thermostat *th, int speed, int fan);
92
93 static int
write_reg(struct thermostat * th,int reg,u8 data)94 write_reg(struct thermostat* th, int reg, u8 data)
95 {
96 u8 tmp[2];
97 int rc;
98
99 tmp[0] = reg;
100 tmp[1] = data;
101 rc = i2c_master_send(th->clt, (const char *)tmp, 2);
102 if (rc < 0)
103 return rc;
104 if (rc != 2)
105 return -ENODEV;
106 return 0;
107 }
108
109 static int
read_reg(struct thermostat * th,int reg)110 read_reg(struct thermostat* th, int reg)
111 {
112 u8 reg_addr, data;
113 int rc;
114
115 reg_addr = (u8)reg;
116 rc = i2c_master_send(th->clt, ®_addr, 1);
117 if (rc < 0)
118 return rc;
119 if (rc != 1)
120 return -ENODEV;
121 rc = i2c_master_recv(th->clt, (char *)&data, 1);
122 if (rc < 0)
123 return rc;
124 return data;
125 }
126
read_fan_speed(struct thermostat * th,u8 addr)127 static int read_fan_speed(struct thermostat *th, u8 addr)
128 {
129 u8 tmp[2];
130 u16 res;
131
132 /* should start with low byte */
133 tmp[1] = read_reg(th, addr);
134 tmp[0] = read_reg(th, addr + 1);
135
136 res = tmp[1] + (tmp[0] << 8);
137 /* "a value of 0xffff means that the fan has stopped" */
138 return (res == 0xffff ? 0 : (90000*60)/res);
139 }
140
write_both_fan_speed(struct thermostat * th,int speed)141 static void write_both_fan_speed(struct thermostat *th, int speed)
142 {
143 write_fan_speed(th, speed, 0);
144 if (th->type == ADT7460)
145 write_fan_speed(th, speed, 1);
146 }
147
write_fan_speed(struct thermostat * th,int speed,int fan)148 static void write_fan_speed(struct thermostat *th, int speed, int fan)
149 {
150 u8 manual;
151
152 if (speed > 0xff)
153 speed = 0xff;
154 else if (speed < -1)
155 speed = 0;
156
157 if (th->type == ADT7467 && fan == 1)
158 return;
159
160 if (th->last_speed[fan] != speed) {
161 if (verbose) {
162 if (speed == -1)
163 printk(KERN_DEBUG "adt746x: Setting speed to automatic "
164 "for %s fan.\n", sensor_location[fan+1]);
165 else
166 printk(KERN_DEBUG "adt746x: Setting speed to %d "
167 "for %s fan.\n", speed, sensor_location[fan+1]);
168 }
169 } else
170 return;
171
172 if (speed >= 0) {
173 manual = read_reg(th, MANUAL_MODE[fan]);
174 manual &= ~INVERT_MASK;
175 write_reg(th, MANUAL_MODE[fan],
176 manual | MANUAL_MASK | th->pwm_inv[fan]);
177 write_reg(th, FAN_SPD_SET[fan], speed);
178 } else {
179 /* back to automatic */
180 if(th->type == ADT7460) {
181 manual = read_reg(th,
182 MANUAL_MODE[fan]) & (~MANUAL_MASK);
183 manual &= ~INVERT_MASK;
184 manual |= th->pwm_inv[fan];
185 write_reg(th,
186 MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
187 } else {
188 manual = read_reg(th, MANUAL_MODE[fan]);
189 manual &= ~INVERT_MASK;
190 manual |= th->pwm_inv[fan];
191 write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
192 }
193 }
194
195 th->last_speed[fan] = speed;
196 }
197
read_sensors(struct thermostat * th)198 static void read_sensors(struct thermostat *th)
199 {
200 int i = 0;
201
202 for (i = 0; i < 3; i++)
203 th->temps[i] = read_reg(th, TEMP_REG[i]);
204 }
205
206 #ifdef DEBUG
display_stats(struct thermostat * th)207 static void display_stats(struct thermostat *th)
208 {
209 if (th->temps[0] != th->cached_temp[0]
210 || th->temps[1] != th->cached_temp[1]
211 || th->temps[2] != th->cached_temp[2]) {
212 printk(KERN_INFO "adt746x: Temperature infos:"
213 " thermostats: %d,%d,%d;"
214 " limits: %d,%d,%d;"
215 " fan speed: %d RPM\n",
216 th->temps[0], th->temps[1], th->temps[2],
217 th->limits[0], th->limits[1], th->limits[2],
218 read_fan_speed(th, FAN_SPEED[0]));
219 }
220 th->cached_temp[0] = th->temps[0];
221 th->cached_temp[1] = th->temps[1];
222 th->cached_temp[2] = th->temps[2];
223 }
224 #endif
225
update_fans_speed(struct thermostat * th)226 static void update_fans_speed (struct thermostat *th)
227 {
228 int lastvar = 0; /* last variation, for iBook */
229 int i = 0;
230
231 /* we don't care about local sensor, so we start at sensor 1 */
232 for (i = 1; i < 3; i++) {
233 bool started = false;
234 int fan_number = (th->type == ADT7460 && i == 2);
235 int var = th->temps[i] - th->limits[i];
236
237 if (var > -1) {
238 int step = (255 - fan_speed) / 7;
239 int new_speed = 0;
240
241 /* hysteresis : change fan speed only if variation is
242 * more than two degrees */
243 if (abs(var - th->last_var[fan_number]) < 2)
244 continue;
245
246 started = true;
247 new_speed = fan_speed + ((var-1)*step);
248
249 if (new_speed < fan_speed)
250 new_speed = fan_speed;
251 if (new_speed > 255)
252 new_speed = 255;
253
254 if (verbose)
255 printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
256 "(limit exceeded by %d on %s)\n",
257 new_speed, var,
258 sensor_location[fan_number+1]);
259 write_both_fan_speed(th, new_speed);
260 th->last_var[fan_number] = var;
261 } else if (var < -2) {
262 /* don't stop fan if sensor2 is cold and sensor1 is not
263 * so cold (lastvar >= -1) */
264 if (i == 2 && lastvar < -1) {
265 if (th->last_speed[fan_number] != 0)
266 if (verbose)
267 printk(KERN_DEBUG "adt746x: Stopping "
268 "fans.\n");
269 write_both_fan_speed(th, 0);
270 }
271 }
272
273 lastvar = var;
274
275 if (started)
276 return; /* we don't want to re-stop the fan
277 * if sensor1 is heating and sensor2 is not */
278 }
279 }
280
monitor_task(void * arg)281 static int monitor_task(void *arg)
282 {
283 struct thermostat* th = arg;
284
285 set_freezable();
286 while(!kthread_should_stop()) {
287 try_to_freeze();
288 msleep_interruptible(2000);
289
290 #ifndef DEBUG
291 if (fan_speed != -1)
292 read_sensors(th);
293 #else
294 read_sensors(th);
295 #endif
296
297 if (fan_speed != -1)
298 update_fans_speed(th);
299
300 #ifdef DEBUG
301 display_stats(th);
302 #endif
303
304 }
305
306 return 0;
307 }
308
set_limit(struct thermostat * th,int i)309 static void set_limit(struct thermostat *th, int i)
310 {
311 /* Set sensor1 limit higher to avoid powerdowns */
312 th->limits[i] = default_limits_chip[i] + limit_adjust;
313 write_reg(th, LIMIT_REG[i], th->limits[i]);
314
315 /* set our limits to normal */
316 th->limits[i] = default_limits_local[i] + limit_adjust;
317 }
318
319 #define BUILD_SHOW_FUNC_INT(name, data) \
320 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
321 { \
322 struct thermostat *th = dev_get_drvdata(dev); \
323 return sprintf(buf, "%d\n", data); \
324 }
325
326 #define BUILD_SHOW_FUNC_INT_LITE(name, data) \
327 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
328 { \
329 return sprintf(buf, "%d\n", data); \
330 }
331
332 #define BUILD_SHOW_FUNC_STR(name, data) \
333 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
334 { \
335 return sprintf(buf, "%s\n", data); \
336 }
337
338 #define BUILD_SHOW_FUNC_FAN(name, data) \
339 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
340 { \
341 struct thermostat *th = dev_get_drvdata(dev); \
342 return sprintf(buf, "%d (%d rpm)\n", \
343 th->last_speed[data], \
344 read_fan_speed(th, FAN_SPEED[data]) \
345 ); \
346 }
347
348 #define BUILD_STORE_FUNC_DEG(name, data) \
349 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
350 { \
351 struct thermostat *th = dev_get_drvdata(dev); \
352 int val; \
353 int i; \
354 val = simple_strtol(buf, NULL, 10); \
355 printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \
356 limit_adjust = val; \
357 for (i=0; i < 3; i++) \
358 set_limit(th, i); \
359 return n; \
360 }
361
362 #define BUILD_STORE_FUNC_INT(name, data) \
363 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
364 { \
365 int val; \
366 val = simple_strtol(buf, NULL, 10); \
367 if (val < 0 || val > 255) \
368 return -EINVAL; \
369 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
370 data = val; \
371 return n; \
372 }
373
374 BUILD_SHOW_FUNC_INT(sensor1_temperature, (read_reg(th, TEMP_REG[1])))
375 BUILD_SHOW_FUNC_INT(sensor2_temperature, (read_reg(th, TEMP_REG[2])))
376 BUILD_SHOW_FUNC_INT(sensor1_limit, th->limits[1])
377 BUILD_SHOW_FUNC_INT(sensor2_limit, th->limits[2])
378 BUILD_SHOW_FUNC_STR(sensor1_location, sensor_location[1])
379 BUILD_SHOW_FUNC_STR(sensor2_location, sensor_location[2])
380
381 BUILD_SHOW_FUNC_INT_LITE(specified_fan_speed, fan_speed)
382 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
383
384 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed, 0)
385 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed, 1)
386
387 BUILD_SHOW_FUNC_INT_LITE(limit_adjust, limit_adjust)
388 BUILD_STORE_FUNC_DEG(limit_adjust, th)
389
390 static DEVICE_ATTR(sensor1_temperature, S_IRUGO,
391 show_sensor1_temperature,NULL);
392 static DEVICE_ATTR(sensor2_temperature, S_IRUGO,
393 show_sensor2_temperature,NULL);
394 static DEVICE_ATTR(sensor1_limit, S_IRUGO,
395 show_sensor1_limit, NULL);
396 static DEVICE_ATTR(sensor2_limit, S_IRUGO,
397 show_sensor2_limit, NULL);
398 static DEVICE_ATTR(sensor1_location, S_IRUGO,
399 show_sensor1_location, NULL);
400 static DEVICE_ATTR(sensor2_location, S_IRUGO,
401 show_sensor2_location, NULL);
402
403 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
404 show_specified_fan_speed,store_specified_fan_speed);
405
406 static DEVICE_ATTR(sensor1_fan_speed, S_IRUGO,
407 show_sensor1_fan_speed, NULL);
408 static DEVICE_ATTR(sensor2_fan_speed, S_IRUGO,
409 show_sensor2_fan_speed, NULL);
410
411 static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
412 show_limit_adjust, store_limit_adjust);
413
thermostat_create_files(struct thermostat * th)414 static void thermostat_create_files(struct thermostat *th)
415 {
416 struct device_node *np = th->clt->dev.of_node;
417 struct device *dev;
418 int err;
419
420 /* To maintain ABI compatibility with userspace, create
421 * the old style platform driver and attach the attributes
422 * to it here
423 */
424 th->pdev = of_platform_device_create(np, "temperatures", NULL);
425 if (!th->pdev)
426 return;
427 dev = &th->pdev->dev;
428 dev_set_drvdata(dev, th);
429 err = device_create_file(dev, &dev_attr_sensor1_temperature);
430 err |= device_create_file(dev, &dev_attr_sensor2_temperature);
431 err |= device_create_file(dev, &dev_attr_sensor1_limit);
432 err |= device_create_file(dev, &dev_attr_sensor2_limit);
433 err |= device_create_file(dev, &dev_attr_sensor1_location);
434 err |= device_create_file(dev, &dev_attr_sensor2_location);
435 err |= device_create_file(dev, &dev_attr_limit_adjust);
436 err |= device_create_file(dev, &dev_attr_specified_fan_speed);
437 err |= device_create_file(dev, &dev_attr_sensor1_fan_speed);
438 if(th->type == ADT7460)
439 err |= device_create_file(dev, &dev_attr_sensor2_fan_speed);
440 if (err)
441 printk(KERN_WARNING
442 "Failed to create temperature attribute file(s).\n");
443 }
444
thermostat_remove_files(struct thermostat * th)445 static void thermostat_remove_files(struct thermostat *th)
446 {
447 struct device *dev;
448
449 if (!th->pdev)
450 return;
451 dev = &th->pdev->dev;
452 device_remove_file(dev, &dev_attr_sensor1_temperature);
453 device_remove_file(dev, &dev_attr_sensor2_temperature);
454 device_remove_file(dev, &dev_attr_sensor1_limit);
455 device_remove_file(dev, &dev_attr_sensor2_limit);
456 device_remove_file(dev, &dev_attr_sensor1_location);
457 device_remove_file(dev, &dev_attr_sensor2_location);
458 device_remove_file(dev, &dev_attr_limit_adjust);
459 device_remove_file(dev, &dev_attr_specified_fan_speed);
460 device_remove_file(dev, &dev_attr_sensor1_fan_speed);
461 if (th->type == ADT7460)
462 device_remove_file(dev, &dev_attr_sensor2_fan_speed);
463 of_device_unregister(th->pdev);
464
465 }
466
probe_thermostat(struct i2c_client * client,const struct i2c_device_id * id)467 static int probe_thermostat(struct i2c_client *client,
468 const struct i2c_device_id *id)
469 {
470 struct device_node *np = client->dev.of_node;
471 struct thermostat* th;
472 const __be32 *prop;
473 int i, rc, vers, offset = 0;
474
475 if (!np)
476 return -ENXIO;
477 prop = of_get_property(np, "hwsensor-params-version", NULL);
478 if (!prop)
479 return -ENXIO;
480 vers = be32_to_cpup(prop);
481 printk(KERN_INFO "adt746x: version %d (%ssupported)\n",
482 vers, vers == 1 ? "" : "un");
483 if (vers != 1)
484 return -ENXIO;
485
486 if (of_get_property(np, "hwsensor-location", NULL)) {
487 for (i = 0; i < 3; i++) {
488 sensor_location[i] = of_get_property(np,
489 "hwsensor-location", NULL) + offset;
490
491 if (sensor_location[i] == NULL)
492 sensor_location[i] = "";
493
494 printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
495 offset += strlen(sensor_location[i]) + 1;
496 }
497 }
498
499 th = kzalloc(sizeof(struct thermostat), GFP_KERNEL);
500 if (!th)
501 return -ENOMEM;
502
503 i2c_set_clientdata(client, th);
504 th->clt = client;
505 th->type = id->driver_data;
506
507 rc = read_reg(th, CONFIG_REG);
508 if (rc < 0) {
509 dev_err(&client->dev, "Thermostat failed to read config!\n");
510 kfree(th);
511 return -ENODEV;
512 }
513
514 /* force manual control to start the fan quieter */
515 if (fan_speed == -1)
516 fan_speed = 64;
517
518 if (th->type == ADT7460) {
519 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
520 /* The 7460 needs to be started explicitly */
521 write_reg(th, CONFIG_REG, 1);
522 } else
523 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
524
525 for (i = 0; i < 3; i++) {
526 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
527 set_limit(th, i);
528 }
529
530 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
531 " to %d, %d, %d\n",
532 th->initial_limits[0], th->initial_limits[1],
533 th->initial_limits[2], th->limits[0], th->limits[1],
534 th->limits[2]);
535
536 /* record invert bit status because fw can corrupt it after suspend */
537 th->pwm_inv[0] = read_reg(th, MANUAL_MODE[0]) & INVERT_MASK;
538 th->pwm_inv[1] = read_reg(th, MANUAL_MODE[1]) & INVERT_MASK;
539
540 /* be sure to really write fan speed the first time */
541 th->last_speed[0] = -2;
542 th->last_speed[1] = -2;
543 th->last_var[0] = -80;
544 th->last_var[1] = -80;
545
546 if (fan_speed != -1) {
547 /* manual mode, stop fans */
548 write_both_fan_speed(th, 0);
549 } else {
550 /* automatic mode */
551 write_both_fan_speed(th, -1);
552 }
553
554 th->thread = kthread_run(monitor_task, th, "kfand");
555 if (th->thread == ERR_PTR(-ENOMEM)) {
556 printk(KERN_INFO "adt746x: Kthread creation failed\n");
557 th->thread = NULL;
558 return -ENOMEM;
559 }
560
561 thermostat_create_files(th);
562
563 return 0;
564 }
565
remove_thermostat(struct i2c_client * client)566 static int remove_thermostat(struct i2c_client *client)
567 {
568 struct thermostat *th = i2c_get_clientdata(client);
569 int i;
570
571 thermostat_remove_files(th);
572
573 if (th->thread != NULL)
574 kthread_stop(th->thread);
575
576 printk(KERN_INFO "adt746x: Putting max temperatures back from "
577 "%d, %d, %d to %d, %d, %d\n",
578 th->limits[0], th->limits[1], th->limits[2],
579 th->initial_limits[0], th->initial_limits[1],
580 th->initial_limits[2]);
581
582 for (i = 0; i < 3; i++)
583 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
584
585 write_both_fan_speed(th, -1);
586
587 kfree(th);
588
589 return 0;
590 }
591
592 static const struct i2c_device_id therm_adt746x_id[] = {
593 { "MAC,adt7460", ADT7460 },
594 { "MAC,adt7467", ADT7467 },
595 { }
596 };
597 MODULE_DEVICE_TABLE(i2c, therm_adt746x_id);
598
599 static struct i2c_driver thermostat_driver = {
600 .driver = {
601 .name = "therm_adt746x",
602 },
603 .probe = probe_thermostat,
604 .remove = remove_thermostat,
605 .id_table = therm_adt746x_id,
606 };
607
thermostat_init(void)608 static int __init thermostat_init(void)
609 {
610 #ifndef CONFIG_I2C_POWERMAC
611 request_module("i2c-powermac");
612 #endif
613
614 return i2c_add_driver(&thermostat_driver);
615 }
616
thermostat_exit(void)617 static void __exit thermostat_exit(void)
618 {
619 i2c_del_driver(&thermostat_driver);
620 }
621
622 module_init(thermostat_init);
623 module_exit(thermostat_exit);
624
