tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/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
28#include <asm/prom.h>
29#include <asm/machdep.h>
30#include <asm/io.h>
31#include <asm/system.h>
32#include <asm/sections.h>
33#include <asm/of_device.h>
34
35#undef DEBUG
36
37#define CONFIG_REG 0x40
38#define MANUAL_MASK 0xe0
39#define AUTO_MASK 0x20
40
41static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
42static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
43static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
44static u8 REM_CONTROL[2] = {0x00, 0x40};
45static u8 FAN_SPEED[2] = {0x28, 0x2a};
46static u8 FAN_SPD_SET[2] = {0x30, 0x31};
47
48static u8 default_limits_local[3] = {70, 50, 70}; /* local, sensor1, sensor2 */
49static u8 default_limits_chip[3] = {80, 65, 80}; /* local, sensor1, sensor2 */
50static const char *sensor_location[3] = {NULL, NULL, NULL};
51
52static int limit_adjust = 0;
53static int fan_speed = -1;
54static int verbose = 0;
55
56MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
57MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
58 "Powerbook G4 Alu");
59MODULE_LICENSE("GPL");
60
61module_param(limit_adjust, int, 0644);
62MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
63 "by N degrees.");
64
65module_param(fan_speed, int, 0644);
66MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
67 "(default 64)");
68
69module_param(verbose, bool, 0);
70MODULE_PARM_DESC(verbose,"Verbose log operations "
71 "(default 0)");
72
73struct 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};
82
83static enum {ADT7460, ADT7467} therm_type;
84static int therm_bus, therm_address;
85static struct of_device * of_dev;
86static struct thermostat* thermostat;
87static struct task_struct *thread_therm = NULL;
88
89static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
90 int busno);
91
92static void write_both_fan_speed(struct thermostat *th, int speed);
93static void write_fan_speed(struct thermostat *th, int speed, int fan);
94
95static int
96write_reg(struct thermostat* th, int reg, u8 data)
97{
98 u8 tmp[2];
99 int rc;
100
101 tmp[0] = reg;
102 tmp[1] = data;
103 rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
104 if (rc < 0)
105 return rc;
106 if (rc != 2)
107 return -ENODEV;
108 return 0;
109}
110
111static int
112read_reg(struct thermostat* th, int reg)
113{
114 u8 reg_addr, data;
115 int rc;
116
117 reg_addr = (u8)reg;
118 rc = i2c_master_send(&th->clt, ®_addr, 1);
119 if (rc < 0)
120 return rc;
121 if (rc != 1)
122 return -ENODEV;
123 rc = i2c_master_recv(&th->clt, (char *)&data, 1);
124 if (rc < 0)
125 return rc;
126 return data;
127}
128
129static int
130attach_thermostat(struct i2c_adapter *adapter)
131{
132 unsigned long bus_no;
133
134 if (strncmp(adapter->name, "uni-n", 5))
135 return -ENODEV;
136 bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
137 if (bus_no != therm_bus)
138 return -ENODEV;
139 return attach_one_thermostat(adapter, therm_address, bus_no);
140}
141
142static int
143detach_thermostat(struct i2c_adapter *adapter)
144{
145 struct thermostat* th;
146 int i;
147
148 if (thermostat == NULL)
149 return 0;
150
151 th = thermostat;
152
153 if (thread_therm != NULL) {
154 kthread_stop(thread_therm);
155 }
156
157 printk(KERN_INFO "adt746x: Putting max temperatures back from "
158 "%d, %d, %d to %d, %d, %d\n",
159 th->limits[0], th->limits[1], th->limits[2],
160 th->initial_limits[0], th->initial_limits[1],
161 th->initial_limits[2]);
162
163 for (i = 0; i < 3; i++)
164 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
165
166 write_both_fan_speed(th, -1);
167
168 i2c_detach_client(&th->clt);
169
170 thermostat = NULL;
171
172 kfree(th);
173
174 return 0;
175}
176
177static struct i2c_driver thermostat_driver = {
178 .driver = {
179 .name = "therm_adt746x",
180 },
181 .attach_adapter = attach_thermostat,
182 .detach_adapter = detach_thermostat,
183};
184
185static int read_fan_speed(struct thermostat *th, u8 addr)
186{
187 u8 tmp[2];
188 u16 res;
189
190 /* should start with low byte */
191 tmp[1] = read_reg(th, addr);
192 tmp[0] = read_reg(th, addr + 1);
193
194 res = tmp[1] + (tmp[0] << 8);
195 /* "a value of 0xffff means that the fan has stopped" */
196 return (res == 0xffff ? 0 : (90000*60)/res);
197}
198
199static void write_both_fan_speed(struct thermostat *th, int speed)
200{
201 write_fan_speed(th, speed, 0);
202 if (therm_type == ADT7460)
203 write_fan_speed(th, speed, 1);
204}
205
206static void write_fan_speed(struct thermostat *th, int speed, int fan)
207{
208 u8 manual;
209
210 if (speed > 0xff)
211 speed = 0xff;
212 else if (speed < -1)
213 speed = 0;
214
215 if (therm_type == ADT7467 && fan == 1)
216 return;
217
218 if (th->last_speed[fan] != speed) {
219 if (verbose) {
220 if (speed == -1)
221 printk(KERN_DEBUG "adt746x: Setting speed to automatic "
222 "for %s fan.\n", sensor_location[fan+1]);
223 else
224 printk(KERN_DEBUG "adt746x: Setting speed to %d "
225 "for %s fan.\n", speed, sensor_location[fan+1]);
226 }
227 } else
228 return;
229
230 if (speed >= 0) {
231 manual = read_reg(th, MANUAL_MODE[fan]);
232 write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
233 write_reg(th, FAN_SPD_SET[fan], speed);
234 } else {
235 /* back to automatic */
236 if(therm_type == ADT7460) {
237 manual = read_reg(th,
238 MANUAL_MODE[fan]) & (~MANUAL_MASK);
239
240 write_reg(th,
241 MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
242 } else {
243 manual = read_reg(th, MANUAL_MODE[fan]);
244 write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
245 }
246 }
247
248 th->last_speed[fan] = speed;
249}
250
251static void read_sensors(struct thermostat *th)
252{
253 int i = 0;
254
255 for (i = 0; i < 3; i++)
256 th->temps[i] = read_reg(th, TEMP_REG[i]);
257}
258
259#ifdef DEBUG
260static void display_stats(struct thermostat *th)
261{
262 if (th->temps[0] != th->cached_temp[0]
263 || th->temps[1] != th->cached_temp[1]
264 || th->temps[2] != th->cached_temp[2]) {
265 printk(KERN_INFO "adt746x: Temperature infos:"
266 " thermostats: %d,%d,%d;"
267 " limits: %d,%d,%d;"
268 " fan speed: %d RPM\n",
269 th->temps[0], th->temps[1], th->temps[2],
270 th->limits[0], th->limits[1], th->limits[2],
271 read_fan_speed(th, FAN_SPEED[0]));
272 }
273 th->cached_temp[0] = th->temps[0];
274 th->cached_temp[1] = th->temps[1];
275 th->cached_temp[2] = th->temps[2];
276}
277#endif
278
279static void update_fans_speed (struct thermostat *th)
280{
281 int lastvar = 0; /* last variation, for iBook */
282 int i = 0;
283
284 /* we don't care about local sensor, so we start at sensor 1 */
285 for (i = 1; i < 3; i++) {
286 int started = 0;
287 int fan_number = (therm_type == ADT7460 && i == 2);
288 int var = th->temps[i] - th->limits[i];
289
290 if (var > -1) {
291 int step = (255 - fan_speed) / 7;
292 int new_speed = 0;
293
294 /* hysteresis : change fan speed only if variation is
295 * more than two degrees */
296 if (abs(var - th->last_var[fan_number]) < 2)
297 continue;
298
299 started = 1;
300 new_speed = fan_speed + ((var-1)*step);
301
302 if (new_speed < fan_speed)
303 new_speed = fan_speed;
304 if (new_speed > 255)
305 new_speed = 255;
306
307 if (verbose)
308 printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
309 "(limit exceeded by %d on %s) \n",
310 new_speed, var,
311 sensor_location[fan_number+1]);
312 write_both_fan_speed(th, new_speed);
313 th->last_var[fan_number] = var;
314 } else if (var < -2) {
315 /* don't stop fan if sensor2 is cold and sensor1 is not
316 * so cold (lastvar >= -1) */
317 if (i == 2 && lastvar < -1) {
318 if (th->last_speed[fan_number] != 0)
319 if (verbose)
320 printk(KERN_DEBUG "adt746x: Stopping "
321 "fans.\n");
322 write_both_fan_speed(th, 0);
323 }
324 }
325
326 lastvar = var;
327
328 if (started)
329 return; /* we don't want to re-stop the fan
330 * if sensor1 is heating and sensor2 is not */
331 }
332}
333
334static int monitor_task(void *arg)
335{
336 struct thermostat* th = arg;
337
338 while(!kthread_should_stop()) {
339 try_to_freeze();
340 msleep_interruptible(2000);
341
342#ifndef DEBUG
343 if (fan_speed != -1)
344 read_sensors(th);
345#else
346 read_sensors(th);
347#endif
348
349 if (fan_speed != -1)
350 update_fans_speed(th);
351
352#ifdef DEBUG
353 display_stats(th);
354#endif
355
356 }
357
358 return 0;
359}
360
361static void set_limit(struct thermostat *th, int i)
362{
363 /* Set sensor1 limit higher to avoid powerdowns */
364 th->limits[i] = default_limits_chip[i] + limit_adjust;
365 write_reg(th, LIMIT_REG[i], th->limits[i]);
366
367 /* set our limits to normal */
368 th->limits[i] = default_limits_local[i] + limit_adjust;
369}
370
371static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
372 int busno)
373{
374 struct thermostat* th;
375 int rc;
376 int i;
377
378 if (thermostat)
379 return 0;
380
381 th = (struct thermostat *)
382 kmalloc(sizeof(struct thermostat), GFP_KERNEL);
383
384 if (!th)
385 return -ENOMEM;
386
387 memset(th, 0, sizeof(*th));
388 th->clt.addr = addr;
389 th->clt.adapter = adapter;
390 th->clt.driver = &thermostat_driver;
391 strcpy(th->clt.name, "thermostat");
392
393 rc = read_reg(th, 0);
394 if (rc < 0) {
395 printk(KERN_ERR "adt746x: Thermostat failed to read config "
396 "from bus %d !\n",
397 busno);
398 kfree(th);
399 return -ENODEV;
400 }
401
402 /* force manual control to start the fan quieter */
403 if (fan_speed == -1)
404 fan_speed = 64;
405
406 if(therm_type == ADT7460) {
407 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
408 /* The 7460 needs to be started explicitly */
409 write_reg(th, CONFIG_REG, 1);
410 } else
411 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
412
413 for (i = 0; i < 3; i++) {
414 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
415 set_limit(th, i);
416 }
417
418 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
419 " to %d, %d, %d\n",
420 th->initial_limits[0], th->initial_limits[1],
421 th->initial_limits[2], th->limits[0], th->limits[1],
422 th->limits[2]);
423
424 thermostat = th;
425
426 if (i2c_attach_client(&th->clt)) {
427 printk(KERN_INFO "adt746x: Thermostat failed to attach "
428 "client !\n");
429 thermostat = NULL;
430 kfree(th);
431 return -ENODEV;
432 }
433
434 /* be sure to really write fan speed the first time */
435 th->last_speed[0] = -2;
436 th->last_speed[1] = -2;
437 th->last_var[0] = -80;
438 th->last_var[1] = -80;
439
440 if (fan_speed != -1) {
441 /* manual mode, stop fans */
442 write_both_fan_speed(th, 0);
443 } else {
444 /* automatic mode */
445 write_both_fan_speed(th, -1);
446 }
447
448 thread_therm = kthread_run(monitor_task, th, "kfand");
449
450 if (thread_therm == ERR_PTR(-ENOMEM)) {
451 printk(KERN_INFO "adt746x: Kthread creation failed\n");
452 thread_therm = NULL;
453 return -ENOMEM;
454 }
455
456 return 0;
457}
458
459/*
460 * Now, unfortunately, sysfs doesn't give us a nice void * we could
461 * pass around to the attribute functions, so we don't really have
462 * choice but implement a bunch of them...
463 *
464 * FIXME, it does now...
465 */
466#define BUILD_SHOW_FUNC_INT(name, data) \
467static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
468{ \
469 return sprintf(buf, "%d\n", data); \
470}
471
472#define BUILD_SHOW_FUNC_STR(name, data) \
473static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
474{ \
475 return sprintf(buf, "%s\n", data); \
476}
477
478#define BUILD_SHOW_FUNC_FAN(name, data) \
479static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
480{ \
481 return sprintf(buf, "%d (%d rpm)\n", \
482 thermostat->last_speed[data], \
483 read_fan_speed(thermostat, FAN_SPEED[data]) \
484 ); \
485}
486
487#define BUILD_STORE_FUNC_DEG(name, data) \
488static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
489{ \
490 int val; \
491 int i; \
492 val = simple_strtol(buf, NULL, 10); \
493 printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \
494 limit_adjust = val; \
495 for (i=0; i < 3; i++) \
496 set_limit(thermostat, i); \
497 return n; \
498}
499
500#define BUILD_STORE_FUNC_INT(name, data) \
501static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
502{ \
503 u32 val; \
504 val = simple_strtoul(buf, NULL, 10); \
505 if (val < 0 || val > 255) \
506 return -EINVAL; \
507 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
508 data = val; \
509 return n; \
510}
511
512BUILD_SHOW_FUNC_INT(sensor1_temperature, (read_reg(thermostat, TEMP_REG[1])))
513BUILD_SHOW_FUNC_INT(sensor2_temperature, (read_reg(thermostat, TEMP_REG[2])))
514BUILD_SHOW_FUNC_INT(sensor1_limit, thermostat->limits[1])
515BUILD_SHOW_FUNC_INT(sensor2_limit, thermostat->limits[2])
516BUILD_SHOW_FUNC_STR(sensor1_location, sensor_location[1])
517BUILD_SHOW_FUNC_STR(sensor2_location, sensor_location[2])
518
519BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
520BUILD_SHOW_FUNC_FAN(sensor1_fan_speed, 0)
521BUILD_SHOW_FUNC_FAN(sensor2_fan_speed, 1)
522
523BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
524BUILD_SHOW_FUNC_INT(limit_adjust, limit_adjust)
525BUILD_STORE_FUNC_DEG(limit_adjust, thermostat)
526
527static DEVICE_ATTR(sensor1_temperature, S_IRUGO,
528 show_sensor1_temperature,NULL);
529static DEVICE_ATTR(sensor2_temperature, S_IRUGO,
530 show_sensor2_temperature,NULL);
531static DEVICE_ATTR(sensor1_limit, S_IRUGO,
532 show_sensor1_limit, NULL);
533static DEVICE_ATTR(sensor2_limit, S_IRUGO,
534 show_sensor2_limit, NULL);
535static DEVICE_ATTR(sensor1_location, S_IRUGO,
536 show_sensor1_location, NULL);
537static DEVICE_ATTR(sensor2_location, S_IRUGO,
538 show_sensor2_location, NULL);
539
540static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
541 show_specified_fan_speed,store_specified_fan_speed);
542
543static DEVICE_ATTR(sensor1_fan_speed, S_IRUGO,
544 show_sensor1_fan_speed, NULL);
545static DEVICE_ATTR(sensor2_fan_speed, S_IRUGO,
546 show_sensor2_fan_speed, NULL);
547
548static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
549 show_limit_adjust, store_limit_adjust);
550
551
552static int __init
553thermostat_init(void)
554{
555 struct device_node* np;
556 const u32 *prop;
557 int i = 0, offset = 0;
558
559 np = of_find_node_by_name(NULL, "fan");
560 if (!np)
561 return -ENODEV;
562 if (device_is_compatible(np, "adt7460"))
563 therm_type = ADT7460;
564 else if (device_is_compatible(np, "adt7467"))
565 therm_type = ADT7467;
566 else
567 return -ENODEV;
568
569 prop = get_property(np, "hwsensor-params-version", NULL);
570 printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
571 (*prop == 1)?"":"un");
572 if (*prop != 1)
573 return -ENODEV;
574
575 prop = get_property(np, "reg", NULL);
576 if (!prop)
577 return -ENODEV;
578
579 /* look for bus either by path or using "reg" */
580 if (strstr(np->full_name, "/i2c-bus@") != NULL) {
581 const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9);
582 therm_bus = tmp_bus[0]-'0';
583 } else {
584 therm_bus = ((*prop) >> 8) & 0x0f;
585 }
586
587 therm_address = ((*prop) & 0xff) >> 1;
588
589 printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, "
590 "limit_adjust: %d, fan_speed: %d\n",
591 therm_bus, therm_address, limit_adjust, fan_speed);
592
593 if (get_property(np, "hwsensor-location", NULL)) {
594 for (i = 0; i < 3; i++) {
595 sensor_location[i] = get_property(np,
596 "hwsensor-location", NULL) + offset;
597
598 if (sensor_location[i] == NULL)
599 sensor_location[i] = "";
600
601 printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
602 offset += strlen(sensor_location[i]) + 1;
603 }
604 } else {
605 sensor_location[0] = "?";
606 sensor_location[1] = "?";
607 sensor_location[2] = "?";
608 }
609
610 of_dev = of_platform_device_create(np, "temperatures", NULL);
611
612 if (of_dev == NULL) {
613 printk(KERN_ERR "Can't register temperatures device !\n");
614 return -ENODEV;
615 }
616
617 device_create_file(&of_dev->dev, &dev_attr_sensor1_temperature);
618 device_create_file(&of_dev->dev, &dev_attr_sensor2_temperature);
619 device_create_file(&of_dev->dev, &dev_attr_sensor1_limit);
620 device_create_file(&of_dev->dev, &dev_attr_sensor2_limit);
621 device_create_file(&of_dev->dev, &dev_attr_sensor1_location);
622 device_create_file(&of_dev->dev, &dev_attr_sensor2_location);
623 device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
624 device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
625 device_create_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
626 if(therm_type == ADT7460)
627 device_create_file(&of_dev->dev, &dev_attr_sensor2_fan_speed);
628
629#ifndef CONFIG_I2C_POWERMAC
630 request_module("i2c-powermac");
631#endif
632
633 return i2c_add_driver(&thermostat_driver);
634}
635
636static void __exit
637thermostat_exit(void)
638{
639 if (of_dev) {
640 device_remove_file(&of_dev->dev, &dev_attr_sensor1_temperature);
641 device_remove_file(&of_dev->dev, &dev_attr_sensor2_temperature);
642 device_remove_file(&of_dev->dev, &dev_attr_sensor1_limit);
643 device_remove_file(&of_dev->dev, &dev_attr_sensor2_limit);
644 device_remove_file(&of_dev->dev, &dev_attr_sensor1_location);
645 device_remove_file(&of_dev->dev, &dev_attr_sensor2_location);
646 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
647 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
648 device_remove_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
649
650 if(therm_type == ADT7460)
651 device_remove_file(&of_dev->dev,
652 &dev_attr_sensor2_fan_speed);
653
654 of_device_unregister(of_dev);
655 }
656 i2c_del_driver(&thermostat_driver);
657}
658
659module_init(thermostat_init);
660module_exit(thermostat_exit);