Commit | Line | Data |
---|---|---|
75722d39 BH |
1 | /* |
2 | * Windfarm PowerMac thermal control. Core | |
3 | * | |
4 | * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp. | |
5 | * <benh@kernel.crashing.org> | |
6 | * | |
7 | * Released under the term of the GNU GPL v2. | |
8 | * | |
9 | * This core code tracks the list of sensors & controls, register | |
10 | * clients, and holds the kernel thread used for control. | |
11 | * | |
12 | * TODO: | |
13 | * | |
14 | * Add some information about sensor/control type and data format to | |
15 | * sensors/controls, and have the sysfs attribute stuff be moved | |
16 | * generically here instead of hard coded in the platform specific | |
17 | * driver as it us currently | |
18 | * | |
19 | * This however requires solving some annoying lifetime issues with | |
20 | * sysfs which doesn't seem to have lifetime rules for struct attribute, | |
21 | * I may have to create full features kobjects for every sensor/control | |
22 | * instead which is a bit of an overkill imho | |
23 | */ | |
24 | ||
25 | #include <linux/types.h> | |
26 | #include <linux/errno.h> | |
27 | #include <linux/kernel.h> | |
5a0e3ad6 | 28 | #include <linux/slab.h> |
75722d39 BH |
29 | #include <linux/init.h> |
30 | #include <linux/spinlock.h> | |
75722d39 BH |
31 | #include <linux/kthread.h> |
32 | #include <linux/jiffies.h> | |
33 | #include <linux/reboot.h> | |
34 | #include <linux/device.h> | |
35 | #include <linux/platform_device.h> | |
837e9594 | 36 | #include <linux/mutex.h> |
7dfb7103 | 37 | #include <linux/freezer.h> |
75722d39 | 38 | |
b55fafc5 BH |
39 | #include <asm/prom.h> |
40 | ||
75722d39 BH |
41 | #include "windfarm.h" |
42 | ||
43 | #define VERSION "0.2" | |
44 | ||
45 | #undef DEBUG | |
46 | ||
47 | #ifdef DEBUG | |
48 | #define DBG(args...) printk(args) | |
49 | #else | |
50 | #define DBG(args...) do { } while(0) | |
51 | #endif | |
52 | ||
53 | static LIST_HEAD(wf_controls); | |
54 | static LIST_HEAD(wf_sensors); | |
837e9594 | 55 | static DEFINE_MUTEX(wf_lock); |
e041c683 | 56 | static BLOCKING_NOTIFIER_HEAD(wf_client_list); |
75722d39 BH |
57 | static int wf_client_count; |
58 | static unsigned int wf_overtemp; | |
59 | static unsigned int wf_overtemp_counter; | |
60 | struct task_struct *wf_thread; | |
61 | ||
ac171c46 BH |
62 | static struct platform_device wf_platform_device = { |
63 | .name = "windfarm", | |
64 | }; | |
65 | ||
75722d39 BH |
66 | /* |
67 | * Utilities & tick thread | |
68 | */ | |
69 | ||
70 | static inline void wf_notify(int event, void *param) | |
71 | { | |
e041c683 | 72 | blocking_notifier_call_chain(&wf_client_list, event, param); |
75722d39 BH |
73 | } |
74 | ||
75 | int wf_critical_overtemp(void) | |
76 | { | |
77 | static char * critical_overtemp_path = "/sbin/critical_overtemp"; | |
78 | char *argv[] = { critical_overtemp_path, NULL }; | |
79 | static char *envp[] = { "HOME=/", | |
80 | "TERM=linux", | |
81 | "PATH=/sbin:/usr/sbin:/bin:/usr/bin", | |
82 | NULL }; | |
83 | ||
86313c48 JF |
84 | return call_usermodehelper(critical_overtemp_path, |
85 | argv, envp, UMH_WAIT_EXEC); | |
75722d39 BH |
86 | } |
87 | EXPORT_SYMBOL_GPL(wf_critical_overtemp); | |
88 | ||
89 | static int wf_thread_func(void *data) | |
90 | { | |
91 | unsigned long next, delay; | |
92 | ||
93 | next = jiffies; | |
94 | ||
95 | DBG("wf: thread started\n"); | |
96 | ||
83144186 | 97 | set_freezable(); |
67b60518 JB |
98 | while (!kthread_should_stop()) { |
99 | try_to_freeze(); | |
100 | ||
75722d39 BH |
101 | if (time_after_eq(jiffies, next)) { |
102 | wf_notify(WF_EVENT_TICK, NULL); | |
103 | if (wf_overtemp) { | |
104 | wf_overtemp_counter++; | |
105 | /* 10 seconds overtemp, notify userland */ | |
106 | if (wf_overtemp_counter > 10) | |
107 | wf_critical_overtemp(); | |
108 | /* 30 seconds, shutdown */ | |
109 | if (wf_overtemp_counter > 30) { | |
110 | printk(KERN_ERR "windfarm: Overtemp " | |
111 | "for more than 30" | |
112 | " seconds, shutting down\n"); | |
113 | machine_power_off(); | |
114 | } | |
115 | } | |
116 | next += HZ; | |
117 | } | |
118 | ||
119 | delay = next - jiffies; | |
120 | if (delay <= HZ) | |
121 | schedule_timeout_interruptible(delay); | |
75722d39 BH |
122 | } |
123 | ||
124 | DBG("wf: thread stopped\n"); | |
125 | ||
126 | return 0; | |
127 | } | |
128 | ||
129 | static void wf_start_thread(void) | |
130 | { | |
131 | wf_thread = kthread_run(wf_thread_func, NULL, "kwindfarm"); | |
132 | if (IS_ERR(wf_thread)) { | |
133 | printk(KERN_ERR "windfarm: failed to create thread,err %ld\n", | |
134 | PTR_ERR(wf_thread)); | |
135 | wf_thread = NULL; | |
136 | } | |
137 | } | |
138 | ||
139 | ||
140 | static void wf_stop_thread(void) | |
141 | { | |
142 | if (wf_thread) | |
143 | kthread_stop(wf_thread); | |
144 | wf_thread = NULL; | |
145 | } | |
146 | ||
147 | /* | |
148 | * Controls | |
149 | */ | |
150 | ||
151 | static void wf_control_release(struct kref *kref) | |
152 | { | |
153 | struct wf_control *ct = container_of(kref, struct wf_control, ref); | |
154 | ||
155 | DBG("wf: Deleting control %s\n", ct->name); | |
156 | ||
157 | if (ct->ops && ct->ops->release) | |
158 | ct->ops->release(ct); | |
159 | else | |
160 | kfree(ct); | |
161 | } | |
162 | ||
ac171c46 BH |
163 | static ssize_t wf_show_control(struct device *dev, |
164 | struct device_attribute *attr, char *buf) | |
165 | { | |
166 | struct wf_control *ctrl = container_of(attr, struct wf_control, attr); | |
167 | s32 val = 0; | |
168 | int err; | |
169 | ||
170 | err = ctrl->ops->get_value(ctrl, &val); | |
171 | if (err < 0) | |
172 | return err; | |
173 | return sprintf(buf, "%d\n", val); | |
174 | } | |
175 | ||
176 | /* This is really only for debugging... */ | |
177 | static ssize_t wf_store_control(struct device *dev, | |
178 | struct device_attribute *attr, | |
179 | const char *buf, size_t count) | |
180 | { | |
181 | struct wf_control *ctrl = container_of(attr, struct wf_control, attr); | |
182 | int val; | |
183 | int err; | |
184 | char *endp; | |
185 | ||
186 | val = simple_strtoul(buf, &endp, 0); | |
187 | while (endp < buf + count && (*endp == ' ' || *endp == '\n')) | |
188 | ++endp; | |
189 | if (endp - buf < count) | |
190 | return -EINVAL; | |
191 | err = ctrl->ops->set_value(ctrl, val); | |
192 | if (err < 0) | |
193 | return err; | |
194 | return count; | |
195 | } | |
196 | ||
75722d39 BH |
197 | int wf_register_control(struct wf_control *new_ct) |
198 | { | |
199 | struct wf_control *ct; | |
200 | ||
837e9594 | 201 | mutex_lock(&wf_lock); |
75722d39 BH |
202 | list_for_each_entry(ct, &wf_controls, link) { |
203 | if (!strcmp(ct->name, new_ct->name)) { | |
204 | printk(KERN_WARNING "windfarm: trying to register" | |
205 | " duplicate control %s\n", ct->name); | |
837e9594 | 206 | mutex_unlock(&wf_lock); |
75722d39 BH |
207 | return -EEXIST; |
208 | } | |
209 | } | |
210 | kref_init(&new_ct->ref); | |
211 | list_add(&new_ct->link, &wf_controls); | |
212 | ||
12765517 | 213 | sysfs_attr_init(&new_ct->attr.attr); |
ac171c46 | 214 | new_ct->attr.attr.name = new_ct->name; |
ac171c46 BH |
215 | new_ct->attr.attr.mode = 0644; |
216 | new_ct->attr.show = wf_show_control; | |
217 | new_ct->attr.store = wf_store_control; | |
ccd308f0 SR |
218 | if (device_create_file(&wf_platform_device.dev, &new_ct->attr)) |
219 | printk(KERN_WARNING "windfarm: device_create_file failed" | |
220 | " for %s\n", new_ct->name); | |
221 | /* the subsystem still does useful work without the file */ | |
ac171c46 | 222 | |
75722d39 BH |
223 | DBG("wf: Registered control %s\n", new_ct->name); |
224 | ||
225 | wf_notify(WF_EVENT_NEW_CONTROL, new_ct); | |
837e9594 | 226 | mutex_unlock(&wf_lock); |
75722d39 BH |
227 | |
228 | return 0; | |
229 | } | |
230 | EXPORT_SYMBOL_GPL(wf_register_control); | |
231 | ||
232 | void wf_unregister_control(struct wf_control *ct) | |
233 | { | |
837e9594 | 234 | mutex_lock(&wf_lock); |
75722d39 | 235 | list_del(&ct->link); |
837e9594 | 236 | mutex_unlock(&wf_lock); |
75722d39 BH |
237 | |
238 | DBG("wf: Unregistered control %s\n", ct->name); | |
239 | ||
240 | kref_put(&ct->ref, wf_control_release); | |
241 | } | |
242 | EXPORT_SYMBOL_GPL(wf_unregister_control); | |
243 | ||
244 | struct wf_control * wf_find_control(const char *name) | |
245 | { | |
246 | struct wf_control *ct; | |
247 | ||
837e9594 | 248 | mutex_lock(&wf_lock); |
75722d39 BH |
249 | list_for_each_entry(ct, &wf_controls, link) { |
250 | if (!strcmp(ct->name, name)) { | |
251 | if (wf_get_control(ct)) | |
252 | ct = NULL; | |
837e9594 | 253 | mutex_unlock(&wf_lock); |
75722d39 BH |
254 | return ct; |
255 | } | |
256 | } | |
837e9594 | 257 | mutex_unlock(&wf_lock); |
75722d39 BH |
258 | return NULL; |
259 | } | |
260 | EXPORT_SYMBOL_GPL(wf_find_control); | |
261 | ||
262 | int wf_get_control(struct wf_control *ct) | |
263 | { | |
264 | if (!try_module_get(ct->ops->owner)) | |
265 | return -ENODEV; | |
266 | kref_get(&ct->ref); | |
267 | return 0; | |
268 | } | |
269 | EXPORT_SYMBOL_GPL(wf_get_control); | |
270 | ||
271 | void wf_put_control(struct wf_control *ct) | |
272 | { | |
273 | struct module *mod = ct->ops->owner; | |
274 | kref_put(&ct->ref, wf_control_release); | |
275 | module_put(mod); | |
276 | } | |
277 | EXPORT_SYMBOL_GPL(wf_put_control); | |
278 | ||
279 | ||
280 | /* | |
281 | * Sensors | |
282 | */ | |
283 | ||
284 | ||
285 | static void wf_sensor_release(struct kref *kref) | |
286 | { | |
287 | struct wf_sensor *sr = container_of(kref, struct wf_sensor, ref); | |
288 | ||
289 | DBG("wf: Deleting sensor %s\n", sr->name); | |
290 | ||
291 | if (sr->ops && sr->ops->release) | |
292 | sr->ops->release(sr); | |
293 | else | |
294 | kfree(sr); | |
295 | } | |
296 | ||
ac171c46 BH |
297 | static ssize_t wf_show_sensor(struct device *dev, |
298 | struct device_attribute *attr, char *buf) | |
299 | { | |
300 | struct wf_sensor *sens = container_of(attr, struct wf_sensor, attr); | |
301 | s32 val = 0; | |
302 | int err; | |
303 | ||
304 | err = sens->ops->get_value(sens, &val); | |
305 | if (err < 0) | |
306 | return err; | |
307 | return sprintf(buf, "%d.%03d\n", FIX32TOPRINT(val)); | |
308 | } | |
309 | ||
75722d39 BH |
310 | int wf_register_sensor(struct wf_sensor *new_sr) |
311 | { | |
312 | struct wf_sensor *sr; | |
313 | ||
837e9594 | 314 | mutex_lock(&wf_lock); |
75722d39 BH |
315 | list_for_each_entry(sr, &wf_sensors, link) { |
316 | if (!strcmp(sr->name, new_sr->name)) { | |
317 | printk(KERN_WARNING "windfarm: trying to register" | |
318 | " duplicate sensor %s\n", sr->name); | |
837e9594 | 319 | mutex_unlock(&wf_lock); |
75722d39 BH |
320 | return -EEXIST; |
321 | } | |
322 | } | |
323 | kref_init(&new_sr->ref); | |
324 | list_add(&new_sr->link, &wf_sensors); | |
325 | ||
b35c74da | 326 | sysfs_attr_init(&new_sr->attr.attr); |
ac171c46 | 327 | new_sr->attr.attr.name = new_sr->name; |
ac171c46 BH |
328 | new_sr->attr.attr.mode = 0444; |
329 | new_sr->attr.show = wf_show_sensor; | |
330 | new_sr->attr.store = NULL; | |
ccd308f0 SR |
331 | if (device_create_file(&wf_platform_device.dev, &new_sr->attr)) |
332 | printk(KERN_WARNING "windfarm: device_create_file failed" | |
333 | " for %s\n", new_sr->name); | |
334 | /* the subsystem still does useful work without the file */ | |
ac171c46 | 335 | |
75722d39 BH |
336 | DBG("wf: Registered sensor %s\n", new_sr->name); |
337 | ||
338 | wf_notify(WF_EVENT_NEW_SENSOR, new_sr); | |
837e9594 | 339 | mutex_unlock(&wf_lock); |
75722d39 BH |
340 | |
341 | return 0; | |
342 | } | |
343 | EXPORT_SYMBOL_GPL(wf_register_sensor); | |
344 | ||
345 | void wf_unregister_sensor(struct wf_sensor *sr) | |
346 | { | |
837e9594 | 347 | mutex_lock(&wf_lock); |
75722d39 | 348 | list_del(&sr->link); |
837e9594 | 349 | mutex_unlock(&wf_lock); |
75722d39 BH |
350 | |
351 | DBG("wf: Unregistered sensor %s\n", sr->name); | |
352 | ||
353 | wf_put_sensor(sr); | |
354 | } | |
355 | EXPORT_SYMBOL_GPL(wf_unregister_sensor); | |
356 | ||
357 | struct wf_sensor * wf_find_sensor(const char *name) | |
358 | { | |
359 | struct wf_sensor *sr; | |
360 | ||
837e9594 | 361 | mutex_lock(&wf_lock); |
75722d39 BH |
362 | list_for_each_entry(sr, &wf_sensors, link) { |
363 | if (!strcmp(sr->name, name)) { | |
364 | if (wf_get_sensor(sr)) | |
365 | sr = NULL; | |
837e9594 | 366 | mutex_unlock(&wf_lock); |
75722d39 BH |
367 | return sr; |
368 | } | |
369 | } | |
837e9594 | 370 | mutex_unlock(&wf_lock); |
75722d39 BH |
371 | return NULL; |
372 | } | |
373 | EXPORT_SYMBOL_GPL(wf_find_sensor); | |
374 | ||
375 | int wf_get_sensor(struct wf_sensor *sr) | |
376 | { | |
377 | if (!try_module_get(sr->ops->owner)) | |
378 | return -ENODEV; | |
379 | kref_get(&sr->ref); | |
380 | return 0; | |
381 | } | |
382 | EXPORT_SYMBOL_GPL(wf_get_sensor); | |
383 | ||
384 | void wf_put_sensor(struct wf_sensor *sr) | |
385 | { | |
386 | struct module *mod = sr->ops->owner; | |
387 | kref_put(&sr->ref, wf_sensor_release); | |
388 | module_put(mod); | |
389 | } | |
390 | EXPORT_SYMBOL_GPL(wf_put_sensor); | |
391 | ||
392 | ||
393 | /* | |
394 | * Client & notification | |
395 | */ | |
396 | ||
397 | int wf_register_client(struct notifier_block *nb) | |
398 | { | |
399 | int rc; | |
400 | struct wf_control *ct; | |
401 | struct wf_sensor *sr; | |
402 | ||
837e9594 | 403 | mutex_lock(&wf_lock); |
e041c683 | 404 | rc = blocking_notifier_chain_register(&wf_client_list, nb); |
75722d39 BH |
405 | if (rc != 0) |
406 | goto bail; | |
407 | wf_client_count++; | |
408 | list_for_each_entry(ct, &wf_controls, link) | |
409 | wf_notify(WF_EVENT_NEW_CONTROL, ct); | |
410 | list_for_each_entry(sr, &wf_sensors, link) | |
411 | wf_notify(WF_EVENT_NEW_SENSOR, sr); | |
412 | if (wf_client_count == 1) | |
413 | wf_start_thread(); | |
414 | bail: | |
837e9594 | 415 | mutex_unlock(&wf_lock); |
75722d39 BH |
416 | return rc; |
417 | } | |
418 | EXPORT_SYMBOL_GPL(wf_register_client); | |
419 | ||
420 | int wf_unregister_client(struct notifier_block *nb) | |
421 | { | |
837e9594 | 422 | mutex_lock(&wf_lock); |
e041c683 | 423 | blocking_notifier_chain_unregister(&wf_client_list, nb); |
75722d39 BH |
424 | wf_client_count++; |
425 | if (wf_client_count == 0) | |
426 | wf_stop_thread(); | |
837e9594 | 427 | mutex_unlock(&wf_lock); |
75722d39 BH |
428 | |
429 | return 0; | |
430 | } | |
431 | EXPORT_SYMBOL_GPL(wf_unregister_client); | |
432 | ||
433 | void wf_set_overtemp(void) | |
434 | { | |
837e9594 | 435 | mutex_lock(&wf_lock); |
75722d39 BH |
436 | wf_overtemp++; |
437 | if (wf_overtemp == 1) { | |
438 | printk(KERN_WARNING "windfarm: Overtemp condition detected !\n"); | |
439 | wf_overtemp_counter = 0; | |
440 | wf_notify(WF_EVENT_OVERTEMP, NULL); | |
441 | } | |
837e9594 | 442 | mutex_unlock(&wf_lock); |
75722d39 BH |
443 | } |
444 | EXPORT_SYMBOL_GPL(wf_set_overtemp); | |
445 | ||
446 | void wf_clear_overtemp(void) | |
447 | { | |
837e9594 | 448 | mutex_lock(&wf_lock); |
75722d39 BH |
449 | WARN_ON(wf_overtemp == 0); |
450 | if (wf_overtemp == 0) { | |
837e9594 | 451 | mutex_unlock(&wf_lock); |
75722d39 BH |
452 | return; |
453 | } | |
454 | wf_overtemp--; | |
455 | if (wf_overtemp == 0) { | |
456 | printk(KERN_WARNING "windfarm: Overtemp condition cleared !\n"); | |
457 | wf_notify(WF_EVENT_NORMALTEMP, NULL); | |
458 | } | |
837e9594 | 459 | mutex_unlock(&wf_lock); |
75722d39 BH |
460 | } |
461 | EXPORT_SYMBOL_GPL(wf_clear_overtemp); | |
462 | ||
463 | int wf_is_overtemp(void) | |
464 | { | |
465 | return (wf_overtemp != 0); | |
466 | } | |
467 | EXPORT_SYMBOL_GPL(wf_is_overtemp); | |
468 | ||
75722d39 BH |
469 | static int __init windfarm_core_init(void) |
470 | { | |
471 | DBG("wf: core loaded\n"); | |
472 | ||
b55fafc5 | 473 | /* Don't register on old machines that use therm_pm72 for now */ |
71a157e8 GL |
474 | if (of_machine_is_compatible("PowerMac7,2") || |
475 | of_machine_is_compatible("PowerMac7,3") || | |
476 | of_machine_is_compatible("RackMac3,1")) | |
b55fafc5 | 477 | return -ENODEV; |
75722d39 BH |
478 | platform_device_register(&wf_platform_device); |
479 | return 0; | |
480 | } | |
481 | ||
482 | static void __exit windfarm_core_exit(void) | |
483 | { | |
484 | BUG_ON(wf_client_count != 0); | |
485 | ||
486 | DBG("wf: core unloaded\n"); | |
487 | ||
488 | platform_device_unregister(&wf_platform_device); | |
489 | } | |
490 | ||
491 | ||
492 | module_init(windfarm_core_init); | |
493 | module_exit(windfarm_core_exit); | |
494 | ||
495 | MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); | |
496 | MODULE_DESCRIPTION("Core component of PowerMac thermal control"); | |
497 | MODULE_LICENSE("GPL"); | |
498 |