Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
[linux-2.6] / drivers / macintosh / windfarm_pm112.c
1 /*
2  * Windfarm PowerMac thermal control.
3  * Control loops for machines with SMU and PPC970MP processors.
4  *
5  * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
6  * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
7  *
8  * Use and redistribute under the terms of the GNU GPL v2.
9  */
10 #include <linux/types.h>
11 #include <linux/errno.h>
12 #include <linux/kernel.h>
13 #include <linux/device.h>
14 #include <linux/platform_device.h>
15 #include <linux/reboot.h>
16 #include <asm/prom.h>
17 #include <asm/smu.h>
18
19 #include "windfarm.h"
20 #include "windfarm_pid.h"
21
22 #define VERSION "0.2"
23
24 #define DEBUG
25 #undef LOTSA_DEBUG
26
27 #ifdef DEBUG
28 #define DBG(args...)    printk(args)
29 #else
30 #define DBG(args...)    do { } while(0)
31 #endif
32
33 #ifdef LOTSA_DEBUG
34 #define DBG_LOTS(args...)       printk(args)
35 #else
36 #define DBG_LOTS(args...)       do { } while(0)
37 #endif
38
39 /* define this to force CPU overtemp to 60 degree, useful for testing
40  * the overtemp code
41  */
42 #undef HACKED_OVERTEMP
43
44 /* We currently only handle 2 chips, 4 cores... */
45 #define NR_CHIPS        2
46 #define NR_CORES        4
47 #define NR_CPU_FANS     3 * NR_CHIPS
48
49 /* Controls and sensors */
50 static struct wf_sensor *sens_cpu_temp[NR_CORES];
51 static struct wf_sensor *sens_cpu_power[NR_CORES];
52 static struct wf_sensor *hd_temp;
53 static struct wf_sensor *slots_power;
54 static struct wf_sensor *u4_temp;
55
56 static struct wf_control *cpu_fans[NR_CPU_FANS];
57 static char *cpu_fan_names[NR_CPU_FANS] = {
58         "cpu-rear-fan-0",
59         "cpu-rear-fan-1",
60         "cpu-front-fan-0",
61         "cpu-front-fan-1",
62         "cpu-pump-0",
63         "cpu-pump-1",
64 };
65 static struct wf_control *cpufreq_clamp;
66
67 /* Second pump isn't required (and isn't actually present) */
68 #define CPU_FANS_REQD           (NR_CPU_FANS - 2)
69 #define FIRST_PUMP              4
70 #define LAST_PUMP               5
71
72 /* We keep a temperature history for average calculation of 180s */
73 #define CPU_TEMP_HIST_SIZE      180
74
75 /* Scale factor for fan speed, *100 */
76 static int cpu_fan_scale[NR_CPU_FANS] = {
77         100,
78         100,
79         97,             /* inlet fans run at 97% of exhaust fan */
80         97,
81         100,            /* updated later */
82         100,            /* updated later */
83 };
84
85 static struct wf_control *backside_fan;
86 static struct wf_control *slots_fan;
87 static struct wf_control *drive_bay_fan;
88
89 /* PID loop state */
90 static struct wf_cpu_pid_state cpu_pid[NR_CORES];
91 static u32 cpu_thist[CPU_TEMP_HIST_SIZE];
92 static int cpu_thist_pt;
93 static s64 cpu_thist_total;
94 static s32 cpu_all_tmax = 100 << 16;
95 static int cpu_last_target;
96 static struct wf_pid_state backside_pid;
97 static int backside_tick;
98 static struct wf_pid_state slots_pid;
99 static int slots_started;
100 static struct wf_pid_state drive_bay_pid;
101 static int drive_bay_tick;
102
103 static int nr_cores;
104 static int have_all_controls;
105 static int have_all_sensors;
106 static int started;
107
108 static int failure_state;
109 #define FAILURE_SENSOR          1
110 #define FAILURE_FAN             2
111 #define FAILURE_PERM            4
112 #define FAILURE_LOW_OVERTEMP    8
113 #define FAILURE_HIGH_OVERTEMP   16
114
115 /* Overtemp values */
116 #define LOW_OVER_AVERAGE        0
117 #define LOW_OVER_IMMEDIATE      (10 << 16)
118 #define LOW_OVER_CLEAR          ((-10) << 16)
119 #define HIGH_OVER_IMMEDIATE     (14 << 16)
120 #define HIGH_OVER_AVERAGE       (10 << 16)
121 #define HIGH_OVER_IMMEDIATE     (14 << 16)
122
123
124 /* Implementation... */
125 static int create_cpu_loop(int cpu)
126 {
127         int chip = cpu / 2;
128         int core = cpu & 1;
129         struct smu_sdbp_header *hdr;
130         struct smu_sdbp_cpupiddata *piddata;
131         struct wf_cpu_pid_param pid;
132         struct wf_control *main_fan = cpu_fans[0];
133         s32 tmax;
134         int fmin;
135
136         /* Get PID params from the appropriate SAT */
137         hdr = smu_sat_get_sdb_partition(chip, 0xC8 + core, NULL);
138         if (hdr == NULL) {
139                 printk(KERN_WARNING"windfarm: can't get CPU PID fan config\n");
140                 return -EINVAL;
141         }
142         piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
143
144         /* Get FVT params to get Tmax; if not found, assume default */
145         hdr = smu_sat_get_sdb_partition(chip, 0xC4 + core, NULL);
146         if (hdr) {
147                 struct smu_sdbp_fvt *fvt = (struct smu_sdbp_fvt *)&hdr[1];
148                 tmax = fvt->maxtemp << 16;
149         } else
150                 tmax = 95 << 16;        /* default to 95 degrees C */
151
152         /* We keep a global tmax for overtemp calculations */
153         if (tmax < cpu_all_tmax)
154                 cpu_all_tmax = tmax;
155
156         /*
157          * Darwin has a minimum fan speed of 1000 rpm for the 4-way and
158          * 515 for the 2-way.  That appears to be overkill, so for now,
159          * impose a minimum of 750 or 515.
160          */
161         fmin = (nr_cores > 2) ? 750 : 515;
162
163         /* Initialize PID loop */
164         pid.interval = 1;       /* seconds */
165         pid.history_len = piddata->history_len;
166         pid.gd = piddata->gd;
167         pid.gp = piddata->gp;
168         pid.gr = piddata->gr / piddata->history_len;
169         pid.pmaxadj = (piddata->max_power << 16) - (piddata->power_adj << 8);
170         pid.ttarget = tmax - (piddata->target_temp_delta << 16);
171         pid.tmax = tmax;
172         pid.min = main_fan->ops->get_min(main_fan);
173         pid.max = main_fan->ops->get_max(main_fan);
174         if (pid.min < fmin)
175                 pid.min = fmin;
176
177         wf_cpu_pid_init(&cpu_pid[cpu], &pid);
178         return 0;
179 }
180
181 static void cpu_max_all_fans(void)
182 {
183         int i;
184
185         /* We max all CPU fans in case of a sensor error. We also do the
186          * cpufreq clamping now, even if it's supposedly done later by the
187          * generic code anyway, we do it earlier here to react faster
188          */
189         if (cpufreq_clamp)
190                 wf_control_set_max(cpufreq_clamp);
191         for (i = 0; i < NR_CPU_FANS; ++i)
192                 if (cpu_fans[i])
193                         wf_control_set_max(cpu_fans[i]);
194 }
195
196 static int cpu_check_overtemp(s32 temp)
197 {
198         int new_state = 0;
199         s32 t_avg, t_old;
200
201         /* First check for immediate overtemps */
202         if (temp >= (cpu_all_tmax + LOW_OVER_IMMEDIATE)) {
203                 new_state |= FAILURE_LOW_OVERTEMP;
204                 if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
205                         printk(KERN_ERR "windfarm: Overtemp due to immediate CPU"
206                                " temperature !\n");
207         }
208         if (temp >= (cpu_all_tmax + HIGH_OVER_IMMEDIATE)) {
209                 new_state |= FAILURE_HIGH_OVERTEMP;
210                 if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
211                         printk(KERN_ERR "windfarm: Critical overtemp due to"
212                                " immediate CPU temperature !\n");
213         }
214
215         /* We calculate a history of max temperatures and use that for the
216          * overtemp management
217          */
218         t_old = cpu_thist[cpu_thist_pt];
219         cpu_thist[cpu_thist_pt] = temp;
220         cpu_thist_pt = (cpu_thist_pt + 1) % CPU_TEMP_HIST_SIZE;
221         cpu_thist_total -= t_old;
222         cpu_thist_total += temp;
223         t_avg = cpu_thist_total / CPU_TEMP_HIST_SIZE;
224
225         DBG_LOTS("t_avg = %d.%03d (out: %d.%03d, in: %d.%03d)\n",
226                  FIX32TOPRINT(t_avg), FIX32TOPRINT(t_old), FIX32TOPRINT(temp));
227
228         /* Now check for average overtemps */
229         if (t_avg >= (cpu_all_tmax + LOW_OVER_AVERAGE)) {
230                 new_state |= FAILURE_LOW_OVERTEMP;
231                 if ((failure_state & FAILURE_LOW_OVERTEMP) == 0)
232                         printk(KERN_ERR "windfarm: Overtemp due to average CPU"
233                                " temperature !\n");
234         }
235         if (t_avg >= (cpu_all_tmax + HIGH_OVER_AVERAGE)) {
236                 new_state |= FAILURE_HIGH_OVERTEMP;
237                 if ((failure_state & FAILURE_HIGH_OVERTEMP) == 0)
238                         printk(KERN_ERR "windfarm: Critical overtemp due to"
239                                " average CPU temperature !\n");
240         }
241
242         /* Now handle overtemp conditions. We don't currently use the windfarm
243          * overtemp handling core as it's not fully suited to the needs of those
244          * new machine. This will be fixed later.
245          */
246         if (new_state) {
247                 /* High overtemp -> immediate shutdown */
248                 if (new_state & FAILURE_HIGH_OVERTEMP)
249                         machine_power_off();
250                 if ((failure_state & new_state) != new_state)
251                         cpu_max_all_fans();
252                 failure_state |= new_state;
253         } else if ((failure_state & FAILURE_LOW_OVERTEMP) &&
254                    (temp < (cpu_all_tmax + LOW_OVER_CLEAR))) {
255                 printk(KERN_ERR "windfarm: Overtemp condition cleared !\n");
256                 failure_state &= ~FAILURE_LOW_OVERTEMP;
257         }
258
259         return failure_state & (FAILURE_LOW_OVERTEMP | FAILURE_HIGH_OVERTEMP);
260 }
261
262 static void cpu_fans_tick(void)
263 {
264         int err, cpu;
265         s32 greatest_delta = 0;
266         s32 temp, power, t_max = 0;
267         int i, t, target = 0;
268         struct wf_sensor *sr;
269         struct wf_control *ct;
270         struct wf_cpu_pid_state *sp;
271
272         DBG_LOTS(KERN_DEBUG);
273         for (cpu = 0; cpu < nr_cores; ++cpu) {
274                 /* Get CPU core temperature */
275                 sr = sens_cpu_temp[cpu];
276                 err = sr->ops->get_value(sr, &temp);
277                 if (err) {
278                         DBG("\n");
279                         printk(KERN_WARNING "windfarm: CPU %d temperature "
280                                "sensor error %d\n", cpu, err);
281                         failure_state |= FAILURE_SENSOR;
282                         cpu_max_all_fans();
283                         return;
284                 }
285
286                 /* Keep track of highest temp */
287                 t_max = max(t_max, temp);
288
289                 /* Get CPU power */
290                 sr = sens_cpu_power[cpu];
291                 err = sr->ops->get_value(sr, &power);
292                 if (err) {
293                         DBG("\n");
294                         printk(KERN_WARNING "windfarm: CPU %d power "
295                                "sensor error %d\n", cpu, err);
296                         failure_state |= FAILURE_SENSOR;
297                         cpu_max_all_fans();
298                         return;
299                 }
300
301                 /* Run PID */
302                 sp = &cpu_pid[cpu];
303                 t = wf_cpu_pid_run(sp, power, temp);
304
305                 if (cpu == 0 || sp->last_delta > greatest_delta) {
306                         greatest_delta = sp->last_delta;
307                         target = t;
308                 }
309                 DBG_LOTS("[%d] P=%d.%.3d T=%d.%.3d ",
310                     cpu, FIX32TOPRINT(power), FIX32TOPRINT(temp));
311         }
312         DBG_LOTS("fans = %d, t_max = %d.%03d\n", target, FIX32TOPRINT(t_max));
313
314         /* Darwin limits decrease to 20 per iteration */
315         if (target < (cpu_last_target - 20))
316                 target = cpu_last_target - 20;
317         cpu_last_target = target;
318         for (cpu = 0; cpu < nr_cores; ++cpu)
319                 cpu_pid[cpu].target = target;
320
321         /* Handle possible overtemps */
322         if (cpu_check_overtemp(t_max))
323                 return;
324
325         /* Set fans */
326         for (i = 0; i < NR_CPU_FANS; ++i) {
327                 ct = cpu_fans[i];
328                 if (ct == NULL)
329                         continue;
330                 err = ct->ops->set_value(ct, target * cpu_fan_scale[i] / 100);
331                 if (err) {
332                         printk(KERN_WARNING "windfarm: fan %s reports "
333                                "error %d\n", ct->name, err);
334                         failure_state |= FAILURE_FAN;
335                         break;
336                 }
337         }
338 }
339
340 /* Backside/U4 fan */
341 static struct wf_pid_param backside_param = {
342         .interval       = 5,
343         .history_len    = 2,
344         .gd             = 48 << 20,
345         .gp             = 5 << 20,
346         .gr             = 0,
347         .itarget        = 64 << 16,
348         .additive       = 1,
349 };
350
351 static void backside_fan_tick(void)
352 {
353         s32 temp;
354         int speed;
355         int err;
356
357         if (!backside_fan || !u4_temp)
358                 return;
359         if (!backside_tick) {
360                 /* first time; initialize things */
361                 printk(KERN_INFO "windfarm: Backside control loop started.\n");
362                 backside_param.min = backside_fan->ops->get_min(backside_fan);
363                 backside_param.max = backside_fan->ops->get_max(backside_fan);
364                 wf_pid_init(&backside_pid, &backside_param);
365                 backside_tick = 1;
366         }
367         if (--backside_tick > 0)
368                 return;
369         backside_tick = backside_pid.param.interval;
370
371         err = u4_temp->ops->get_value(u4_temp, &temp);
372         if (err) {
373                 printk(KERN_WARNING "windfarm: U4 temp sensor error %d\n",
374                        err);
375                 failure_state |= FAILURE_SENSOR;
376                 wf_control_set_max(backside_fan);
377                 return;
378         }
379         speed = wf_pid_run(&backside_pid, temp);
380         DBG_LOTS("backside PID temp=%d.%.3d speed=%d\n",
381                  FIX32TOPRINT(temp), speed);
382
383         err = backside_fan->ops->set_value(backside_fan, speed);
384         if (err) {
385                 printk(KERN_WARNING "windfarm: backside fan error %d\n", err);
386                 failure_state |= FAILURE_FAN;
387         }
388 }
389
390 /* Drive bay fan */
391 static struct wf_pid_param drive_bay_prm = {
392         .interval       = 5,
393         .history_len    = 2,
394         .gd             = 30 << 20,
395         .gp             = 5 << 20,
396         .gr             = 0,
397         .itarget        = 40 << 16,
398         .additive       = 1,
399 };
400
401 static void drive_bay_fan_tick(void)
402 {
403         s32 temp;
404         int speed;
405         int err;
406
407         if (!drive_bay_fan || !hd_temp)
408                 return;
409         if (!drive_bay_tick) {
410                 /* first time; initialize things */
411                 printk(KERN_INFO "windfarm: Drive bay control loop started.\n");
412                 drive_bay_prm.min = drive_bay_fan->ops->get_min(drive_bay_fan);
413                 drive_bay_prm.max = drive_bay_fan->ops->get_max(drive_bay_fan);
414                 wf_pid_init(&drive_bay_pid, &drive_bay_prm);
415                 drive_bay_tick = 1;
416         }
417         if (--drive_bay_tick > 0)
418                 return;
419         drive_bay_tick = drive_bay_pid.param.interval;
420
421         err = hd_temp->ops->get_value(hd_temp, &temp);
422         if (err) {
423                 printk(KERN_WARNING "windfarm: drive bay temp sensor "
424                        "error %d\n", err);
425                 failure_state |= FAILURE_SENSOR;
426                 wf_control_set_max(drive_bay_fan);
427                 return;
428         }
429         speed = wf_pid_run(&drive_bay_pid, temp);
430         DBG_LOTS("drive_bay PID temp=%d.%.3d speed=%d\n",
431                  FIX32TOPRINT(temp), speed);
432
433         err = drive_bay_fan->ops->set_value(drive_bay_fan, speed);
434         if (err) {
435                 printk(KERN_WARNING "windfarm: drive bay fan error %d\n", err);
436                 failure_state |= FAILURE_FAN;
437         }
438 }
439
440 /* PCI slots area fan */
441 /* This makes the fan speed proportional to the power consumed */
442 static struct wf_pid_param slots_param = {
443         .interval       = 1,
444         .history_len    = 2,
445         .gd             = 0,
446         .gp             = 0,
447         .gr             = 0x1277952,
448         .itarget        = 0,
449         .min            = 1560,
450         .max            = 3510,
451 };
452
453 static void slots_fan_tick(void)
454 {
455         s32 power;
456         int speed;
457         int err;
458
459         if (!slots_fan || !slots_power)
460                 return;
461         if (!slots_started) {
462                 /* first time; initialize things */
463                 printk(KERN_INFO "windfarm: Slots control loop started.\n");
464                 wf_pid_init(&slots_pid, &slots_param);
465                 slots_started = 1;
466         }
467
468         err = slots_power->ops->get_value(slots_power, &power);
469         if (err) {
470                 printk(KERN_WARNING "windfarm: slots power sensor error %d\n",
471                        err);
472                 failure_state |= FAILURE_SENSOR;
473                 wf_control_set_max(slots_fan);
474                 return;
475         }
476         speed = wf_pid_run(&slots_pid, power);
477         DBG_LOTS("slots PID power=%d.%.3d speed=%d\n",
478                  FIX32TOPRINT(power), speed);
479
480         err = slots_fan->ops->set_value(slots_fan, speed);
481         if (err) {
482                 printk(KERN_WARNING "windfarm: slots fan error %d\n", err);
483                 failure_state |= FAILURE_FAN;
484         }
485 }
486
487 static void set_fail_state(void)
488 {
489         int i;
490
491         if (cpufreq_clamp)
492                 wf_control_set_max(cpufreq_clamp);
493         for (i = 0; i < NR_CPU_FANS; ++i)
494                 if (cpu_fans[i])
495                         wf_control_set_max(cpu_fans[i]);
496         if (backside_fan)
497                 wf_control_set_max(backside_fan);
498         if (slots_fan)
499                 wf_control_set_max(slots_fan);
500         if (drive_bay_fan)
501                 wf_control_set_max(drive_bay_fan);
502 }
503
504 static void pm112_tick(void)
505 {
506         int i, last_failure;
507
508         if (!started) {
509                 started = 1;
510                 printk(KERN_INFO "windfarm: CPUs control loops started.\n");
511                 for (i = 0; i < nr_cores; ++i) {
512                         if (create_cpu_loop(i) < 0) {
513                                 failure_state = FAILURE_PERM;
514                                 set_fail_state();
515                                 break;
516                         }
517                 }
518                 DBG_LOTS("cpu_all_tmax=%d.%03d\n", FIX32TOPRINT(cpu_all_tmax));
519
520 #ifdef HACKED_OVERTEMP
521                 cpu_all_tmax = 60 << 16;
522 #endif
523         }
524
525         /* Permanent failure, bail out */
526         if (failure_state & FAILURE_PERM)
527                 return;
528         /* Clear all failure bits except low overtemp which will be eventually
529          * cleared by the control loop itself
530          */
531         last_failure = failure_state;
532         failure_state &= FAILURE_LOW_OVERTEMP;
533         cpu_fans_tick();
534         backside_fan_tick();
535         slots_fan_tick();
536         drive_bay_fan_tick();
537
538         DBG_LOTS("last_failure: 0x%x, failure_state: %x\n",
539                  last_failure, failure_state);
540
541         /* Check for failures. Any failure causes cpufreq clamping */
542         if (failure_state && last_failure == 0 && cpufreq_clamp)
543                 wf_control_set_max(cpufreq_clamp);
544         if (failure_state == 0 && last_failure && cpufreq_clamp)
545                 wf_control_set_min(cpufreq_clamp);
546
547         /* That's it for now, we might want to deal with other failures
548          * differently in the future though
549          */
550 }
551
552 static void pm112_new_control(struct wf_control *ct)
553 {
554         int i, max_exhaust;
555
556         if (cpufreq_clamp == NULL && !strcmp(ct->name, "cpufreq-clamp")) {
557                 if (wf_get_control(ct) == 0)
558                         cpufreq_clamp = ct;
559         }
560
561         for (i = 0; i < NR_CPU_FANS; ++i) {
562                 if (!strcmp(ct->name, cpu_fan_names[i])) {
563                         if (cpu_fans[i] == NULL && wf_get_control(ct) == 0)
564                                 cpu_fans[i] = ct;
565                         break;
566                 }
567         }
568         if (i >= NR_CPU_FANS) {
569                 /* not a CPU fan, try the others */
570                 if (!strcmp(ct->name, "backside-fan")) {
571                         if (backside_fan == NULL && wf_get_control(ct) == 0)
572                                 backside_fan = ct;
573                 } else if (!strcmp(ct->name, "slots-fan")) {
574                         if (slots_fan == NULL && wf_get_control(ct) == 0)
575                                 slots_fan = ct;
576                 } else if (!strcmp(ct->name, "drive-bay-fan")) {
577                         if (drive_bay_fan == NULL && wf_get_control(ct) == 0)
578                                 drive_bay_fan = ct;
579                 }
580                 return;
581         }
582
583         for (i = 0; i < CPU_FANS_REQD; ++i)
584                 if (cpu_fans[i] == NULL)
585                         return;
586
587         /* work out pump scaling factors */
588         max_exhaust = cpu_fans[0]->ops->get_max(cpu_fans[0]);
589         for (i = FIRST_PUMP; i <= LAST_PUMP; ++i)
590                 if ((ct = cpu_fans[i]) != NULL)
591                         cpu_fan_scale[i] =
592                                 ct->ops->get_max(ct) * 100 / max_exhaust;
593
594         have_all_controls = 1;
595 }
596
597 static void pm112_new_sensor(struct wf_sensor *sr)
598 {
599         unsigned int i;
600
601         if (!strncmp(sr->name, "cpu-temp-", 9)) {
602                 i = sr->name[9] - '0';
603                 if (sr->name[10] == 0 && i < NR_CORES &&
604                     sens_cpu_temp[i] == NULL && wf_get_sensor(sr) == 0)
605                         sens_cpu_temp[i] = sr;
606
607         } else if (!strncmp(sr->name, "cpu-power-", 10)) {
608                 i = sr->name[10] - '0';
609                 if (sr->name[11] == 0 && i < NR_CORES &&
610                     sens_cpu_power[i] == NULL && wf_get_sensor(sr) == 0)
611                         sens_cpu_power[i] = sr;
612         } else if (!strcmp(sr->name, "hd-temp")) {
613                 if (hd_temp == NULL && wf_get_sensor(sr) == 0)
614                         hd_temp = sr;
615         } else if (!strcmp(sr->name, "slots-power")) {
616                 if (slots_power == NULL && wf_get_sensor(sr) == 0)
617                         slots_power = sr;
618         } else if (!strcmp(sr->name, "backside-temp")) {
619                 if (u4_temp == NULL && wf_get_sensor(sr) == 0)
620                         u4_temp = sr;
621         } else
622                 return;
623
624         /* check if we have all the sensors we need */
625         for (i = 0; i < nr_cores; ++i)
626                 if (sens_cpu_temp[i] == NULL || sens_cpu_power[i] == NULL)
627                         return;
628
629         have_all_sensors = 1;
630 }
631
632 static int pm112_wf_notify(struct notifier_block *self,
633                            unsigned long event, void *data)
634 {
635         switch (event) {
636         case WF_EVENT_NEW_SENSOR:
637                 pm112_new_sensor(data);
638                 break;
639         case WF_EVENT_NEW_CONTROL:
640                 pm112_new_control(data);
641                 break;
642         case WF_EVENT_TICK:
643                 if (have_all_controls && have_all_sensors)
644                         pm112_tick();
645         }
646         return 0;
647 }
648
649 static struct notifier_block pm112_events = {
650         .notifier_call = pm112_wf_notify,
651 };
652
653 static int wf_pm112_probe(struct platform_device *dev)
654 {
655         wf_register_client(&pm112_events);
656         return 0;
657 }
658
659 static int __devexit wf_pm112_remove(struct platform_device *dev)
660 {
661         wf_unregister_client(&pm112_events);
662         /* should release all sensors and controls */
663         return 0;
664 }
665
666 static struct platform_driver wf_pm112_driver = {
667         .probe = wf_pm112_probe,
668         .remove = __devexit_p(wf_pm112_remove),
669         .driver = {
670                 .name = "windfarm",
671                 .owner  = THIS_MODULE,
672         },
673 };
674
675 static int __init wf_pm112_init(void)
676 {
677         struct device_node *cpu;
678
679         if (!machine_is_compatible("PowerMac11,2"))
680                 return -ENODEV;
681
682         /* Count the number of CPU cores */
683         nr_cores = 0;
684         for (cpu = NULL; (cpu = of_find_node_by_type(cpu, "cpu")) != NULL; )
685                 ++nr_cores;
686
687         printk(KERN_INFO "windfarm: initializing for dual-core desktop G5\n");
688
689 #ifdef MODULE
690         request_module("windfarm_smu_controls");
691         request_module("windfarm_smu_sensors");
692         request_module("windfarm_smu_sat");
693         request_module("windfarm_lm75_sensor");
694         request_module("windfarm_max6690_sensor");
695         request_module("windfarm_cpufreq_clamp");
696
697 #endif /* MODULE */
698
699         platform_driver_register(&wf_pm112_driver);
700         return 0;
701 }
702
703 static void __exit wf_pm112_exit(void)
704 {
705         platform_driver_unregister(&wf_pm112_driver);
706 }
707
708 module_init(wf_pm112_init);
709 module_exit(wf_pm112_exit);
710
711 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
712 MODULE_DESCRIPTION("Thermal control for PowerMac11,2");
713 MODULE_LICENSE("GPL");
714 MODULE_ALIAS("platform:windfarm");