V4L/DVB (6305): V4L: videobuf-core.c avoid NULL dereferences in videobuf-core
[linux-2.6/mini2440.git] / drivers / macintosh / therm_adt746x.c
blobf25685b9b7cf51a782c24faaa86bf9b896e4acca
1 /*
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
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
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>
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_platform.h>
35 #undef DEBUG
37 #define CONFIG_REG 0x40
38 #define MANUAL_MASK 0xe0
39 #define AUTO_MASK 0x20
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};
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];
52 static int limit_adjust;
53 static int fan_speed = -1;
54 static int verbose;
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");
61 module_param(limit_adjust, int, 0644);
62 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
63 "by N degrees.");
65 module_param(fan_speed, int, 0644);
66 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
67 "(default 64)");
69 module_param(verbose, bool, 0);
70 MODULE_PARM_DESC(verbose,"Verbose log operations "
71 "(default 0)");
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];
83 static enum {ADT7460, ADT7467} therm_type;
84 static int therm_bus, therm_address;
85 static struct of_device * of_dev;
86 static struct thermostat* thermostat;
87 static struct task_struct *thread_therm = NULL;
89 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
90 int busno);
92 static void write_both_fan_speed(struct thermostat *th, int speed);
93 static void write_fan_speed(struct thermostat *th, int speed, int fan);
95 static int
96 write_reg(struct thermostat* th, int reg, u8 data)
98 u8 tmp[2];
99 int rc;
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;
111 static int
112 read_reg(struct thermostat* th, int reg)
114 u8 reg_addr, data;
115 int rc;
117 reg_addr = (u8)reg;
118 rc = i2c_master_send(&th->clt, &reg_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;
129 static int
130 attach_thermostat(struct i2c_adapter *adapter)
132 unsigned long bus_no;
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);
142 static int
143 detach_thermostat(struct i2c_adapter *adapter)
145 struct thermostat* th;
146 int i;
148 if (thermostat == NULL)
149 return 0;
151 th = thermostat;
153 if (thread_therm != NULL) {
154 kthread_stop(thread_therm);
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]);
163 for (i = 0; i < 3; i++)
164 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
166 write_both_fan_speed(th, -1);
168 i2c_detach_client(&th->clt);
170 thermostat = NULL;
172 kfree(th);
174 return 0;
177 static struct i2c_driver thermostat_driver = {
178 .driver = {
179 .name = "therm_adt746x",
181 .attach_adapter = attach_thermostat,
182 .detach_adapter = detach_thermostat,
185 static int read_fan_speed(struct thermostat *th, u8 addr)
187 u8 tmp[2];
188 u16 res;
190 /* should start with low byte */
191 tmp[1] = read_reg(th, addr);
192 tmp[0] = read_reg(th, addr + 1);
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);
199 static void write_both_fan_speed(struct thermostat *th, int speed)
201 write_fan_speed(th, speed, 0);
202 if (therm_type == ADT7460)
203 write_fan_speed(th, speed, 1);
206 static void write_fan_speed(struct thermostat *th, int speed, int fan)
208 u8 manual;
210 if (speed > 0xff)
211 speed = 0xff;
212 else if (speed < -1)
213 speed = 0;
215 if (therm_type == ADT7467 && fan == 1)
216 return;
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]);
227 } else
228 return;
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);
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));
248 th->last_speed[fan] = speed;
251 static void read_sensors(struct thermostat *th)
253 int i = 0;
255 for (i = 0; i < 3; i++)
256 th->temps[i] = read_reg(th, TEMP_REG[i]);
259 #ifdef DEBUG
260 static void display_stats(struct thermostat *th)
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]));
273 th->cached_temp[0] = th->temps[0];
274 th->cached_temp[1] = th->temps[1];
275 th->cached_temp[2] = th->temps[2];
277 #endif
279 static void update_fans_speed (struct thermostat *th)
281 int lastvar = 0; /* last variation, for iBook */
282 int i = 0;
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];
290 if (var > -1) {
291 int step = (255 - fan_speed) / 7;
292 int new_speed = 0;
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;
299 started = 1;
300 new_speed = fan_speed + ((var-1)*step);
302 if (new_speed < fan_speed)
303 new_speed = fan_speed;
304 if (new_speed > 255)
305 new_speed = 255;
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);
326 lastvar = var;
328 if (started)
329 return; /* we don't want to re-stop the fan
330 * if sensor1 is heating and sensor2 is not */
334 static int monitor_task(void *arg)
336 struct thermostat* th = arg;
338 set_freezable();
339 while(!kthread_should_stop()) {
340 try_to_freeze();
341 msleep_interruptible(2000);
343 #ifndef DEBUG
344 if (fan_speed != -1)
345 read_sensors(th);
346 #else
347 read_sensors(th);
348 #endif
350 if (fan_speed != -1)
351 update_fans_speed(th);
353 #ifdef DEBUG
354 display_stats(th);
355 #endif
359 return 0;
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,
373 int busno)
375 struct thermostat* th;
376 int rc;
377 int i;
379 if (thermostat)
380 return 0;
382 th = (struct thermostat *)
383 kmalloc(sizeof(struct thermostat), GFP_KERNEL);
385 if (!th)
386 return -ENOMEM;
388 memset(th, 0, sizeof(*th));
389 th->clt.addr = addr;
390 th->clt.adapter = adapter;
391 th->clt.driver = &thermostat_driver;
392 strcpy(th->clt.name, "thermostat");
394 rc = read_reg(th, 0);
395 if (rc < 0) {
396 printk(KERN_ERR "adt746x: Thermostat failed to read config "
397 "from bus %d !\n",
398 busno);
399 kfree(th);
400 return -ENODEV;
403 /* force manual control to start the fan quieter */
404 if (fan_speed == -1)
405 fan_speed = 64;
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);
411 } else
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]);
416 set_limit(th, i);
419 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
420 " to %d, %d, %d\n",
421 th->initial_limits[0], th->initial_limits[1],
422 th->initial_limits[2], th->limits[0], th->limits[1],
423 th->limits[2]);
425 thermostat = th;
427 if (i2c_attach_client(&th->clt)) {
428 printk(KERN_INFO "adt746x: Thermostat failed to attach "
429 "client !\n");
430 thermostat = NULL;
431 kfree(th);
432 return -ENODEV;
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);
444 } else {
445 /* automatic mode */
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");
453 thread_therm = NULL;
454 return -ENOMEM;
457 return 0;
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]) \
485 ); \
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) \
491 int val; \
492 int i; \
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); \
498 return n; \
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) \
504 u32 val; \
505 val = simple_strtoul(buf, NULL, 10); \
506 if (val < 0 || val > 255) \
507 return -EINVAL; \
508 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
509 data = val; \
510 return n; \
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);
553 static int __init
554 thermostat_init(void)
556 struct device_node* np;
557 const u32 *prop;
558 int i = 0, offset = 0;
560 np = of_find_node_by_name(NULL, "fan");
561 if (!np)
562 return -ENODEV;
563 if (of_device_is_compatible(np, "adt7460"))
564 therm_type = ADT7460;
565 else if (of_device_is_compatible(np, "adt7467"))
566 therm_type = ADT7467;
567 else
568 return -ENODEV;
570 prop = of_get_property(np, "hwsensor-params-version", NULL);
571 printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
572 (*prop == 1)?"":"un");
573 if (*prop != 1)
574 return -ENODEV;
576 prop = of_get_property(np, "reg", NULL);
577 if (!prop)
578 return -ENODEV;
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';
584 } else {
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 (of_get_property(np, "hwsensor-location", NULL)) {
595 for (i = 0; i < 3; i++) {
596 sensor_location[i] = of_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;
605 } else {
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");
615 return -ENODEV;
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");
632 #endif
634 return i2c_add_driver(&thermostat_driver);
637 static void __exit
638 thermostat_exit(void)
640 if (of_dev) {
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);