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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/sbus/char/bbc_envctrl.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/sbus/char/bbc_envctrl.c')
-rw-r--r--drivers/sbus/char/bbc_envctrl.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/drivers/sbus/char/bbc_envctrl.c b/drivers/sbus/char/bbc_envctrl.c
new file mode 100644
index 000000000000..d5259f7fee6d
--- /dev/null
+++ b/drivers/sbus/char/bbc_envctrl.c
@@ -0,0 +1,645 @@
1/* $Id: bbc_envctrl.c,v 1.4 2001/04/06 16:48:08 davem Exp $
2 * bbc_envctrl.c: UltraSPARC-III environment control driver.
3 *
4 * Copyright (C) 2001 David S. Miller (davem@redhat.com)
5 */
6
7#include <linux/kernel.h>
8#include <linux/sched.h>
9#include <linux/slab.h>
10#include <linux/delay.h>
11#include <asm/oplib.h>
12#include <asm/ebus.h>
13#define __KERNEL_SYSCALLS__
14static int errno;
15#include <asm/unistd.h>
16
17#include "bbc_i2c.h"
18#include "max1617.h"
19
20#undef ENVCTRL_TRACE
21
22/* WARNING: Making changes to this driver is very dangerous.
23 * If you misprogram the sensor chips they can
24 * cut the power on you instantly.
25 */
26
27/* Two temperature sensors exist in the SunBLADE-1000 enclosure.
28 * Both are implemented using max1617 i2c devices. Each max1617
29 * monitors 2 temperatures, one for one of the cpu dies and the other
30 * for the ambient temperature.
31 *
32 * The max1617 is capable of being programmed with power-off
33 * temperature values, one low limit and one high limit. These
34 * can be controlled independently for the cpu or ambient temperature.
35 * If a limit is violated, the power is simply shut off. The frequency
36 * with which the max1617 does temperature sampling can be controlled
37 * as well.
38 *
39 * Three fans exist inside the machine, all three are controlled with
40 * an i2c digital to analog converter. There is a fan directed at the
41 * two processor slots, another for the rest of the enclosure, and the
42 * third is for the power supply. The first two fans may be speed
43 * controlled by changing the voltage fed to them. The third fan may
44 * only be completely off or on. The third fan is meant to only be
45 * disabled/enabled when entering/exiting the lowest power-saving
46 * mode of the machine.
47 *
48 * An environmental control kernel thread periodically monitors all
49 * temperature sensors. Based upon the samples it will adjust the
50 * fan speeds to try and keep the system within a certain temperature
51 * range (the goal being to make the fans as quiet as possible without
52 * allowing the system to get too hot).
53 *
54 * If the temperature begins to rise/fall outside of the acceptable
55 * operating range, a periodic warning will be sent to the kernel log.
56 * The fans will be put on full blast to attempt to deal with this
57 * situation. After exceeding the acceptable operating range by a
58 * certain threshold, the kernel thread will shut down the system.
59 * Here, the thread is attempting to shut the machine down cleanly
60 * before the hardware based power-off event is triggered.
61 */
62
63/* These settings are in Celsius. We use these defaults only
64 * if we cannot interrogate the cpu-fru SEEPROM.
65 */
66struct temp_limits {
67 s8 high_pwroff, high_shutdown, high_warn;
68 s8 low_warn, low_shutdown, low_pwroff;
69};
70
71static struct temp_limits cpu_temp_limits[2] = {
72 { 100, 85, 80, 5, -5, -10 },
73 { 100, 85, 80, 5, -5, -10 },
74};
75
76static struct temp_limits amb_temp_limits[2] = {
77 { 65, 55, 40, 5, -5, -10 },
78 { 65, 55, 40, 5, -5, -10 },
79};
80
81enum fan_action { FAN_SLOWER, FAN_SAME, FAN_FASTER, FAN_FULLBLAST, FAN_STATE_MAX };
82
83struct bbc_cpu_temperature {
84 struct bbc_cpu_temperature *next;
85
86 struct bbc_i2c_client *client;
87 int index;
88
89 /* Current readings, and history. */
90 s8 curr_cpu_temp;
91 s8 curr_amb_temp;
92 s8 prev_cpu_temp;
93 s8 prev_amb_temp;
94 s8 avg_cpu_temp;
95 s8 avg_amb_temp;
96
97 int sample_tick;
98
99 enum fan_action fan_todo[2];
100#define FAN_AMBIENT 0
101#define FAN_CPU 1
102};
103
104struct bbc_cpu_temperature *all_bbc_temps;
105
106struct bbc_fan_control {
107 struct bbc_fan_control *next;
108
109 struct bbc_i2c_client *client;
110 int index;
111
112 int psupply_fan_on;
113 int cpu_fan_speed;
114 int system_fan_speed;
115};
116
117struct bbc_fan_control *all_bbc_fans;
118
119#define CPU_FAN_REG 0xf0
120#define SYS_FAN_REG 0xf2
121#define PSUPPLY_FAN_REG 0xf4
122
123#define FAN_SPEED_MIN 0x0c
124#define FAN_SPEED_MAX 0x3f
125
126#define PSUPPLY_FAN_ON 0x1f
127#define PSUPPLY_FAN_OFF 0x00
128
129static void set_fan_speeds(struct bbc_fan_control *fp)
130{
131 /* Put temperatures into range so we don't mis-program
132 * the hardware.
133 */
134 if (fp->cpu_fan_speed < FAN_SPEED_MIN)
135 fp->cpu_fan_speed = FAN_SPEED_MIN;
136 if (fp->cpu_fan_speed > FAN_SPEED_MAX)
137 fp->cpu_fan_speed = FAN_SPEED_MAX;
138 if (fp->system_fan_speed < FAN_SPEED_MIN)
139 fp->system_fan_speed = FAN_SPEED_MIN;
140 if (fp->system_fan_speed > FAN_SPEED_MAX)
141 fp->system_fan_speed = FAN_SPEED_MAX;
142#ifdef ENVCTRL_TRACE
143 printk("fan%d: Changed fan speed to cpu(%02x) sys(%02x)\n",
144 fp->index,
145 fp->cpu_fan_speed, fp->system_fan_speed);
146#endif
147
148 bbc_i2c_writeb(fp->client, fp->cpu_fan_speed, CPU_FAN_REG);
149 bbc_i2c_writeb(fp->client, fp->system_fan_speed, SYS_FAN_REG);
150 bbc_i2c_writeb(fp->client,
151 (fp->psupply_fan_on ?
152 PSUPPLY_FAN_ON : PSUPPLY_FAN_OFF),
153 PSUPPLY_FAN_REG);
154}
155
156static void get_current_temps(struct bbc_cpu_temperature *tp)
157{
158 tp->prev_amb_temp = tp->curr_amb_temp;
159 bbc_i2c_readb(tp->client,
160 (unsigned char *) &tp->curr_amb_temp,
161 MAX1617_AMB_TEMP);
162 tp->prev_cpu_temp = tp->curr_cpu_temp;
163 bbc_i2c_readb(tp->client,
164 (unsigned char *) &tp->curr_cpu_temp,
165 MAX1617_CPU_TEMP);
166#ifdef ENVCTRL_TRACE
167 printk("temp%d: cpu(%d C) amb(%d C)\n",
168 tp->index,
169 (int) tp->curr_cpu_temp, (int) tp->curr_amb_temp);
170#endif
171}
172
173
174static void do_envctrl_shutdown(struct bbc_cpu_temperature *tp)
175{
176 static int shutting_down = 0;
177 static char *envp[] = { "HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
178 char *argv[] = { "/sbin/shutdown", "-h", "now", NULL };
179 char *type = "???";
180 s8 val = -1;
181
182 if (shutting_down != 0)
183 return;
184
185 if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_shutdown ||
186 tp->curr_amb_temp < amb_temp_limits[tp->index].low_shutdown) {
187 type = "ambient";
188 val = tp->curr_amb_temp;
189 } else if (tp->curr_cpu_temp >= cpu_temp_limits[tp->index].high_shutdown ||
190 tp->curr_cpu_temp < cpu_temp_limits[tp->index].low_shutdown) {
191 type = "CPU";
192 val = tp->curr_cpu_temp;
193 }
194
195 printk(KERN_CRIT "temp%d: Outside of safe %s "
196 "operating temperature, %d C.\n",
197 tp->index, type, val);
198
199 printk(KERN_CRIT "kenvctrld: Shutting down the system now.\n");
200
201 shutting_down = 1;
202 if (execve("/sbin/shutdown", argv, envp) < 0)
203 printk(KERN_CRIT "envctrl: shutdown execution failed\n");
204}
205
206#define WARN_INTERVAL (30 * HZ)
207
208static void analyze_ambient_temp(struct bbc_cpu_temperature *tp, unsigned long *last_warn, int tick)
209{
210 int ret = 0;
211
212 if (time_after(jiffies, (*last_warn + WARN_INTERVAL))) {
213 if (tp->curr_amb_temp >=
214 amb_temp_limits[tp->index].high_warn) {
215 printk(KERN_WARNING "temp%d: "
216 "Above safe ambient operating temperature, %d C.\n",
217 tp->index, (int) tp->curr_amb_temp);
218 ret = 1;
219 } else if (tp->curr_amb_temp <
220 amb_temp_limits[tp->index].low_warn) {
221 printk(KERN_WARNING "temp%d: "
222 "Below safe ambient operating temperature, %d C.\n",
223 tp->index, (int) tp->curr_amb_temp);
224 ret = 1;
225 }
226 if (ret)
227 *last_warn = jiffies;
228 } else if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_warn ||
229 tp->curr_amb_temp < amb_temp_limits[tp->index].low_warn)
230 ret = 1;
231
232 /* Now check the shutdown limits. */
233 if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_shutdown ||
234 tp->curr_amb_temp < amb_temp_limits[tp->index].low_shutdown) {
235 do_envctrl_shutdown(tp);
236 ret = 1;
237 }
238
239 if (ret) {
240 tp->fan_todo[FAN_AMBIENT] = FAN_FULLBLAST;
241 } else if ((tick & (8 - 1)) == 0) {
242 s8 amb_goal_hi = amb_temp_limits[tp->index].high_warn - 10;
243 s8 amb_goal_lo;
244
245 amb_goal_lo = amb_goal_hi - 3;
246
247 /* We do not try to avoid 'too cold' events. Basically we
248 * only try to deal with over-heating and fan noise reduction.
249 */
250 if (tp->avg_amb_temp < amb_goal_hi) {
251 if (tp->avg_amb_temp >= amb_goal_lo)
252 tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
253 else
254 tp->fan_todo[FAN_AMBIENT] = FAN_SLOWER;
255 } else {
256 tp->fan_todo[FAN_AMBIENT] = FAN_FASTER;
257 }
258 } else {
259 tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
260 }
261}
262
263static void analyze_cpu_temp(struct bbc_cpu_temperature *tp, unsigned long *last_warn, int tick)
264{
265 int ret = 0;
266
267 if (time_after(jiffies, (*last_warn + WARN_INTERVAL))) {
268 if (tp->curr_cpu_temp >=
269 cpu_temp_limits[tp->index].high_warn) {
270 printk(KERN_WARNING "temp%d: "
271 "Above safe CPU operating temperature, %d C.\n",
272 tp->index, (int) tp->curr_cpu_temp);
273 ret = 1;
274 } else if (tp->curr_cpu_temp <
275 cpu_temp_limits[tp->index].low_warn) {
276 printk(KERN_WARNING "temp%d: "
277 "Below safe CPU operating temperature, %d C.\n",
278 tp->index, (int) tp->curr_cpu_temp);
279 ret = 1;
280 }
281 if (ret)
282 *last_warn = jiffies;
283 } else if (tp->curr_cpu_temp >= cpu_temp_limits[tp->index].high_warn ||
284 tp->curr_cpu_temp < cpu_temp_limits[tp->index].low_warn)
285 ret = 1;
286
287 /* Now check the shutdown limits. */
288 if (tp->curr_cpu_temp >= cpu_temp_limits[tp->index].high_shutdown ||
289 tp->curr_cpu_temp < cpu_temp_limits[tp->index].low_shutdown) {
290 do_envctrl_shutdown(tp);
291 ret = 1;
292 }
293
294 if (ret) {
295 tp->fan_todo[FAN_CPU] = FAN_FULLBLAST;
296 } else if ((tick & (8 - 1)) == 0) {
297 s8 cpu_goal_hi = cpu_temp_limits[tp->index].high_warn - 10;
298 s8 cpu_goal_lo;
299
300 cpu_goal_lo = cpu_goal_hi - 3;
301
302 /* We do not try to avoid 'too cold' events. Basically we
303 * only try to deal with over-heating and fan noise reduction.
304 */
305 if (tp->avg_cpu_temp < cpu_goal_hi) {
306 if (tp->avg_cpu_temp >= cpu_goal_lo)
307 tp->fan_todo[FAN_CPU] = FAN_SAME;
308 else
309 tp->fan_todo[FAN_CPU] = FAN_SLOWER;
310 } else {
311 tp->fan_todo[FAN_CPU] = FAN_FASTER;
312 }
313 } else {
314 tp->fan_todo[FAN_CPU] = FAN_SAME;
315 }
316}
317
318static void analyze_temps(struct bbc_cpu_temperature *tp, unsigned long *last_warn)
319{
320 tp->avg_amb_temp = (s8)((int)((int)tp->avg_amb_temp + (int)tp->curr_amb_temp) / 2);
321 tp->avg_cpu_temp = (s8)((int)((int)tp->avg_cpu_temp + (int)tp->curr_cpu_temp) / 2);
322
323 analyze_ambient_temp(tp, last_warn, tp->sample_tick);
324 analyze_cpu_temp(tp, last_warn, tp->sample_tick);
325
326 tp->sample_tick++;
327}
328
329static enum fan_action prioritize_fan_action(int which_fan)
330{
331 struct bbc_cpu_temperature *tp;
332 enum fan_action decision = FAN_STATE_MAX;
333
334 /* Basically, prioritize what the temperature sensors
335 * recommend we do, and perform that action on all the
336 * fans.
337 */
338 for (tp = all_bbc_temps; tp; tp = tp->next) {
339 if (tp->fan_todo[which_fan] == FAN_FULLBLAST) {
340 decision = FAN_FULLBLAST;
341 break;
342 }
343 if (tp->fan_todo[which_fan] == FAN_SAME &&
344 decision != FAN_FASTER)
345 decision = FAN_SAME;
346 else if (tp->fan_todo[which_fan] == FAN_FASTER)
347 decision = FAN_FASTER;
348 else if (decision != FAN_FASTER &&
349 decision != FAN_SAME &&
350 tp->fan_todo[which_fan] == FAN_SLOWER)
351 decision = FAN_SLOWER;
352 }
353 if (decision == FAN_STATE_MAX)
354 decision = FAN_SAME;
355
356 return decision;
357}
358
359static int maybe_new_ambient_fan_speed(struct bbc_fan_control *fp)
360{
361 enum fan_action decision = prioritize_fan_action(FAN_AMBIENT);
362 int ret;
363
364 if (decision == FAN_SAME)
365 return 0;
366
367 ret = 1;
368 if (decision == FAN_FULLBLAST) {
369 if (fp->system_fan_speed >= FAN_SPEED_MAX)
370 ret = 0;
371 else
372 fp->system_fan_speed = FAN_SPEED_MAX;
373 } else {
374 if (decision == FAN_FASTER) {
375 if (fp->system_fan_speed >= FAN_SPEED_MAX)
376 ret = 0;
377 else
378 fp->system_fan_speed += 2;
379 } else {
380 int orig_speed = fp->system_fan_speed;
381
382 if (orig_speed <= FAN_SPEED_MIN ||
383 orig_speed <= (fp->cpu_fan_speed - 3))
384 ret = 0;
385 else
386 fp->system_fan_speed -= 1;
387 }
388 }
389
390 return ret;
391}
392
393static int maybe_new_cpu_fan_speed(struct bbc_fan_control *fp)
394{
395 enum fan_action decision = prioritize_fan_action(FAN_CPU);
396 int ret;
397
398 if (decision == FAN_SAME)
399 return 0;
400
401 ret = 1;
402 if (decision == FAN_FULLBLAST) {
403 if (fp->cpu_fan_speed >= FAN_SPEED_MAX)
404 ret = 0;
405 else
406 fp->cpu_fan_speed = FAN_SPEED_MAX;
407 } else {
408 if (decision == FAN_FASTER) {
409 if (fp->cpu_fan_speed >= FAN_SPEED_MAX)
410 ret = 0;
411 else {
412 fp->cpu_fan_speed += 2;
413 if (fp->system_fan_speed <
414 (fp->cpu_fan_speed - 3))
415 fp->system_fan_speed =
416 fp->cpu_fan_speed - 3;
417 }
418 } else {
419 if (fp->cpu_fan_speed <= FAN_SPEED_MIN)
420 ret = 0;
421 else
422 fp->cpu_fan_speed -= 1;
423 }
424 }
425
426 return ret;
427}
428
429static void maybe_new_fan_speeds(struct bbc_fan_control *fp)
430{
431 int new;
432
433 new = maybe_new_ambient_fan_speed(fp);
434 new |= maybe_new_cpu_fan_speed(fp);
435
436 if (new)
437 set_fan_speeds(fp);
438}
439
440static void fans_full_blast(void)
441{
442 struct bbc_fan_control *fp;
443
444 /* Since we will not be monitoring things anymore, put
445 * the fans on full blast.
446 */
447 for (fp = all_bbc_fans; fp; fp = fp->next) {
448 fp->cpu_fan_speed = FAN_SPEED_MAX;
449 fp->system_fan_speed = FAN_SPEED_MAX;
450 fp->psupply_fan_on = 1;
451 set_fan_speeds(fp);
452 }
453}
454
455#define POLL_INTERVAL (5 * 1000)
456static unsigned long last_warning_jiffies;
457static struct task_struct *kenvctrld_task;
458
459static int kenvctrld(void *__unused)
460{
461 daemonize("kenvctrld");
462 allow_signal(SIGKILL);
463 kenvctrld_task = current;
464
465 printk(KERN_INFO "bbc_envctrl: kenvctrld starting...\n");
466 last_warning_jiffies = jiffies - WARN_INTERVAL;
467 for (;;) {
468 struct bbc_cpu_temperature *tp;
469 struct bbc_fan_control *fp;
470
471 msleep_interruptible(POLL_INTERVAL);
472 if (signal_pending(current))
473 break;
474
475 for (tp = all_bbc_temps; tp; tp = tp->next) {
476 get_current_temps(tp);
477 analyze_temps(tp, &last_warning_jiffies);
478 }
479 for (fp = all_bbc_fans; fp; fp = fp->next)
480 maybe_new_fan_speeds(fp);
481 }
482 printk(KERN_INFO "bbc_envctrl: kenvctrld exiting...\n");
483
484 fans_full_blast();
485
486 return 0;
487}
488
489static void attach_one_temp(struct linux_ebus_child *echild, int temp_idx)
490{
491 struct bbc_cpu_temperature *tp = kmalloc(sizeof(*tp), GFP_KERNEL);
492
493 if (!tp)
494 return;
495 memset(tp, 0, sizeof(*tp));
496 tp->client = bbc_i2c_attach(echild);
497 if (!tp->client) {
498 kfree(tp);
499 return;
500 }
501
502 tp->index = temp_idx;
503 {
504 struct bbc_cpu_temperature **tpp = &all_bbc_temps;
505 while (*tpp)
506 tpp = &((*tpp)->next);
507 tp->next = NULL;
508 *tpp = tp;
509 }
510
511 /* Tell it to convert once every 5 seconds, clear all cfg
512 * bits.
513 */
514 bbc_i2c_writeb(tp->client, 0x00, MAX1617_WR_CFG_BYTE);
515 bbc_i2c_writeb(tp->client, 0x02, MAX1617_WR_CVRATE_BYTE);
516
517 /* Program the hard temperature limits into the chip. */
518 bbc_i2c_writeb(tp->client, amb_temp_limits[tp->index].high_pwroff,
519 MAX1617_WR_AMB_HIGHLIM);
520 bbc_i2c_writeb(tp->client, amb_temp_limits[tp->index].low_pwroff,
521 MAX1617_WR_AMB_LOWLIM);
522 bbc_i2c_writeb(tp->client, cpu_temp_limits[tp->index].high_pwroff,
523 MAX1617_WR_CPU_HIGHLIM);
524 bbc_i2c_writeb(tp->client, cpu_temp_limits[tp->index].low_pwroff,
525 MAX1617_WR_CPU_LOWLIM);
526
527 get_current_temps(tp);
528 tp->prev_cpu_temp = tp->avg_cpu_temp = tp->curr_cpu_temp;
529 tp->prev_amb_temp = tp->avg_amb_temp = tp->curr_amb_temp;
530
531 tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
532 tp->fan_todo[FAN_CPU] = FAN_SAME;
533}
534
535static void attach_one_fan(struct linux_ebus_child *echild, int fan_idx)
536{
537 struct bbc_fan_control *fp = kmalloc(sizeof(*fp), GFP_KERNEL);
538
539 if (!fp)
540 return;
541 memset(fp, 0, sizeof(*fp));
542 fp->client = bbc_i2c_attach(echild);
543 if (!fp->client) {
544 kfree(fp);
545 return;
546 }
547
548 fp->index = fan_idx;
549
550 {
551 struct bbc_fan_control **fpp = &all_bbc_fans;
552 while (*fpp)
553 fpp = &((*fpp)->next);
554 fp->next = NULL;
555 *fpp = fp;
556 }
557
558 /* The i2c device controlling the fans is write-only.
559 * So the only way to keep track of the current power
560 * level fed to the fans is via software. Choose half
561 * power for cpu/system and 'on' fo the powersupply fan
562 * and set it now.
563 */
564 fp->psupply_fan_on = 1;
565 fp->cpu_fan_speed = (FAN_SPEED_MAX - FAN_SPEED_MIN) / 2;
566 fp->cpu_fan_speed += FAN_SPEED_MIN;
567 fp->system_fan_speed = (FAN_SPEED_MAX - FAN_SPEED_MIN) / 2;
568 fp->system_fan_speed += FAN_SPEED_MIN;
569
570 set_fan_speeds(fp);
571}
572
573int bbc_envctrl_init(void)
574{
575 struct linux_ebus_child *echild;
576 int temp_index = 0;
577 int fan_index = 0;
578 int devidx = 0;
579 int err = 0;
580
581 while ((echild = bbc_i2c_getdev(devidx++)) != NULL) {
582 if (!strcmp(echild->prom_name, "temperature"))
583 attach_one_temp(echild, temp_index++);
584 if (!strcmp(echild->prom_name, "fan-control"))
585 attach_one_fan(echild, fan_index++);
586 }
587 if (temp_index != 0 && fan_index != 0)
588 err = kernel_thread(kenvctrld, NULL, CLONE_FS | CLONE_FILES);
589 return err;
590}
591
592static void destroy_one_temp(struct bbc_cpu_temperature *tp)
593{
594 bbc_i2c_detach(tp->client);
595 kfree(tp);
596}
597
598static void destroy_one_fan(struct bbc_fan_control *fp)
599{
600 bbc_i2c_detach(fp->client);
601 kfree(fp);
602}
603
604void bbc_envctrl_cleanup(void)
605{
606 struct bbc_cpu_temperature *tp;
607 struct bbc_fan_control *fp;
608
609 if (kenvctrld_task != NULL) {
610 force_sig(SIGKILL, kenvctrld_task);
611 for (;;) {
612 struct task_struct *p;
613 int found = 0;
614
615 read_lock(&tasklist_lock);
616 for_each_process(p) {
617 if (p == kenvctrld_task) {
618 found = 1;
619 break;
620 }
621 }
622 read_unlock(&tasklist_lock);
623 if (!found)
624 break;
625 msleep(1000);
626 }
627 kenvctrld_task = NULL;
628 }
629
630 tp = all_bbc_temps;
631 while (tp != NULL) {
632 struct bbc_cpu_temperature *next = tp->next;
633 destroy_one_temp(tp);
634 tp = next;
635 }
636 all_bbc_temps = NULL;
637
638 fp = all_bbc_fans;
639 while (fp != NULL) {
640 struct bbc_fan_control *next = fp->next;
641 destroy_one_fan(fp);
642 fp = next;
643 }
644 all_bbc_fans = NULL;
645}