Commit | Line | Data |
---|---|---|
a3c98b8b MH |
1 | /* |
2 | * devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework | |
3 | * for Non-CPU Devices. | |
4 | * | |
5 | * Copyright (C) 2011 Samsung Electronics | |
6 | * MyungJoo Ham <myungjoo.ham@samsung.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | */ | |
12 | ||
13 | #include <linux/kernel.h> | |
14 | #include <linux/sched.h> | |
15 | #include <linux/errno.h> | |
16 | #include <linux/err.h> | |
17 | #include <linux/init.h> | |
952f6d13 | 18 | #include <linux/module.h> |
a3c98b8b | 19 | #include <linux/slab.h> |
952f6d13 | 20 | #include <linux/stat.h> |
e4db1c74 | 21 | #include <linux/pm_opp.h> |
a3c98b8b MH |
22 | #include <linux/devfreq.h> |
23 | #include <linux/workqueue.h> | |
24 | #include <linux/platform_device.h> | |
25 | #include <linux/list.h> | |
26 | #include <linux/printk.h> | |
27 | #include <linux/hrtimer.h> | |
8f510aeb | 28 | #include <linux/of.h> |
a3c98b8b MH |
29 | #include "governor.h" |
30 | ||
1a1357ea | 31 | static struct class *devfreq_class; |
a3c98b8b MH |
32 | |
33 | /* | |
7e6fdd4b RV |
34 | * devfreq core provides delayed work based load monitoring helper |
35 | * functions. Governors can use these or can implement their own | |
36 | * monitoring mechanism. | |
a3c98b8b | 37 | */ |
a3c98b8b | 38 | static struct workqueue_struct *devfreq_wq; |
a3c98b8b | 39 | |
3aa173b8 NM |
40 | /* The list of all device-devfreq governors */ |
41 | static LIST_HEAD(devfreq_governor_list); | |
a3c98b8b MH |
42 | /* The list of all device-devfreq */ |
43 | static LIST_HEAD(devfreq_list); | |
44 | static DEFINE_MUTEX(devfreq_list_lock); | |
45 | ||
46 | /** | |
47 | * find_device_devfreq() - find devfreq struct using device pointer | |
48 | * @dev: device pointer used to lookup device devfreq. | |
49 | * | |
50 | * Search the list of device devfreqs and return the matched device's | |
51 | * devfreq info. devfreq_list_lock should be held by the caller. | |
52 | */ | |
53 | static struct devfreq *find_device_devfreq(struct device *dev) | |
54 | { | |
55 | struct devfreq *tmp_devfreq; | |
56 | ||
9348da2f | 57 | if (IS_ERR_OR_NULL(dev)) { |
a3c98b8b MH |
58 | pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); |
59 | return ERR_PTR(-EINVAL); | |
60 | } | |
61 | WARN(!mutex_is_locked(&devfreq_list_lock), | |
62 | "devfreq_list_lock must be locked."); | |
63 | ||
64 | list_for_each_entry(tmp_devfreq, &devfreq_list, node) { | |
65 | if (tmp_devfreq->dev.parent == dev) | |
66 | return tmp_devfreq; | |
67 | } | |
68 | ||
69 | return ERR_PTR(-ENODEV); | |
70 | } | |
71 | ||
e552bbaf JL |
72 | /** |
73 | * devfreq_get_freq_level() - Lookup freq_table for the frequency | |
74 | * @devfreq: the devfreq instance | |
75 | * @freq: the target frequency | |
76 | */ | |
77 | static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq) | |
78 | { | |
79 | int lev; | |
80 | ||
81 | for (lev = 0; lev < devfreq->profile->max_state; lev++) | |
82 | if (freq == devfreq->profile->freq_table[lev]) | |
83 | return lev; | |
84 | ||
85 | return -EINVAL; | |
86 | } | |
87 | ||
0ec09ac2 CC |
88 | /** |
89 | * devfreq_set_freq_table() - Initialize freq_table for the frequency | |
90 | * @devfreq: the devfreq instance | |
91 | */ | |
92 | static void devfreq_set_freq_table(struct devfreq *devfreq) | |
93 | { | |
94 | struct devfreq_dev_profile *profile = devfreq->profile; | |
95 | struct dev_pm_opp *opp; | |
96 | unsigned long freq; | |
97 | int i, count; | |
98 | ||
99 | /* Initialize the freq_table from OPP table */ | |
100 | count = dev_pm_opp_get_opp_count(devfreq->dev.parent); | |
101 | if (count <= 0) | |
102 | return; | |
103 | ||
104 | profile->max_state = count; | |
105 | profile->freq_table = devm_kcalloc(devfreq->dev.parent, | |
106 | profile->max_state, | |
107 | sizeof(*profile->freq_table), | |
108 | GFP_KERNEL); | |
109 | if (!profile->freq_table) { | |
110 | profile->max_state = 0; | |
111 | return; | |
112 | } | |
113 | ||
114 | rcu_read_lock(); | |
115 | for (i = 0, freq = 0; i < profile->max_state; i++, freq++) { | |
116 | opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq); | |
117 | if (IS_ERR(opp)) { | |
118 | devm_kfree(devfreq->dev.parent, profile->freq_table); | |
119 | profile->max_state = 0; | |
120 | rcu_read_unlock(); | |
121 | return; | |
122 | } | |
123 | profile->freq_table[i] = freq; | |
124 | } | |
125 | rcu_read_unlock(); | |
126 | } | |
127 | ||
e552bbaf JL |
128 | /** |
129 | * devfreq_update_status() - Update statistics of devfreq behavior | |
130 | * @devfreq: the devfreq instance | |
131 | * @freq: the update target frequency | |
132 | */ | |
133 | static int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) | |
134 | { | |
e35d35a1 | 135 | int lev, prev_lev, ret = 0; |
e552bbaf JL |
136 | unsigned long cur_time; |
137 | ||
e552bbaf | 138 | cur_time = jiffies; |
e35d35a1 SK |
139 | |
140 | prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq); | |
141 | if (prev_lev < 0) { | |
142 | ret = prev_lev; | |
143 | goto out; | |
144 | } | |
145 | ||
146 | devfreq->time_in_state[prev_lev] += | |
e552bbaf | 147 | cur_time - devfreq->last_stat_updated; |
e35d35a1 SK |
148 | |
149 | lev = devfreq_get_freq_level(devfreq, freq); | |
150 | if (lev < 0) { | |
151 | ret = lev; | |
152 | goto out; | |
153 | } | |
154 | ||
155 | if (lev != prev_lev) { | |
e552bbaf JL |
156 | devfreq->trans_table[(prev_lev * |
157 | devfreq->profile->max_state) + lev]++; | |
158 | devfreq->total_trans++; | |
159 | } | |
e552bbaf | 160 | |
e35d35a1 SK |
161 | out: |
162 | devfreq->last_stat_updated = cur_time; | |
163 | return ret; | |
e552bbaf JL |
164 | } |
165 | ||
3aa173b8 NM |
166 | /** |
167 | * find_devfreq_governor() - find devfreq governor from name | |
168 | * @name: name of the governor | |
169 | * | |
170 | * Search the list of devfreq governors and return the matched | |
171 | * governor's pointer. devfreq_list_lock should be held by the caller. | |
172 | */ | |
173 | static struct devfreq_governor *find_devfreq_governor(const char *name) | |
174 | { | |
175 | struct devfreq_governor *tmp_governor; | |
176 | ||
9348da2f | 177 | if (IS_ERR_OR_NULL(name)) { |
3aa173b8 NM |
178 | pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); |
179 | return ERR_PTR(-EINVAL); | |
180 | } | |
181 | WARN(!mutex_is_locked(&devfreq_list_lock), | |
182 | "devfreq_list_lock must be locked."); | |
183 | ||
184 | list_for_each_entry(tmp_governor, &devfreq_governor_list, node) { | |
185 | if (!strncmp(tmp_governor->name, name, DEVFREQ_NAME_LEN)) | |
186 | return tmp_governor; | |
187 | } | |
188 | ||
189 | return ERR_PTR(-ENODEV); | |
190 | } | |
191 | ||
0fe3a664 CC |
192 | static int devfreq_notify_transition(struct devfreq *devfreq, |
193 | struct devfreq_freqs *freqs, unsigned int state) | |
194 | { | |
195 | if (!devfreq) | |
196 | return -EINVAL; | |
197 | ||
198 | switch (state) { | |
199 | case DEVFREQ_PRECHANGE: | |
200 | srcu_notifier_call_chain(&devfreq->transition_notifier_list, | |
201 | DEVFREQ_PRECHANGE, freqs); | |
202 | break; | |
203 | ||
204 | case DEVFREQ_POSTCHANGE: | |
205 | srcu_notifier_call_chain(&devfreq->transition_notifier_list, | |
206 | DEVFREQ_POSTCHANGE, freqs); | |
207 | break; | |
208 | default: | |
209 | return -EINVAL; | |
210 | } | |
211 | ||
212 | return 0; | |
213 | } | |
214 | ||
7e6fdd4b RV |
215 | /* Load monitoring helper functions for governors use */ |
216 | ||
a3c98b8b MH |
217 | /** |
218 | * update_devfreq() - Reevaluate the device and configure frequency. | |
219 | * @devfreq: the devfreq instance. | |
220 | * | |
221 | * Note: Lock devfreq->lock before calling update_devfreq | |
222 | * This function is exported for governors. | |
223 | */ | |
224 | int update_devfreq(struct devfreq *devfreq) | |
225 | { | |
0fe3a664 CC |
226 | struct devfreq_freqs freqs; |
227 | unsigned long freq, cur_freq; | |
a3c98b8b | 228 | int err = 0; |
ab5f299f | 229 | u32 flags = 0; |
a3c98b8b MH |
230 | |
231 | if (!mutex_is_locked(&devfreq->lock)) { | |
232 | WARN(true, "devfreq->lock must be locked by the caller.\n"); | |
233 | return -EINVAL; | |
234 | } | |
235 | ||
1b5c1be2 NM |
236 | if (!devfreq->governor) |
237 | return -EINVAL; | |
238 | ||
a3c98b8b MH |
239 | /* Reevaluate the proper frequency */ |
240 | err = devfreq->governor->get_target_freq(devfreq, &freq); | |
241 | if (err) | |
242 | return err; | |
243 | ||
ab5f299f | 244 | /* |
d3b7e174 | 245 | * Adjust the frequency with user freq and QoS. |
ab5f299f | 246 | * |
d3b7e174 JM |
247 | * List from the highest priority |
248 | * max_freq | |
ab5f299f MH |
249 | * min_freq |
250 | */ | |
251 | ||
252 | if (devfreq->min_freq && freq < devfreq->min_freq) { | |
253 | freq = devfreq->min_freq; | |
254 | flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */ | |
255 | } | |
256 | if (devfreq->max_freq && freq > devfreq->max_freq) { | |
257 | freq = devfreq->max_freq; | |
258 | flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ | |
259 | } | |
260 | ||
0fe3a664 CC |
261 | if (devfreq->profile->get_cur_freq) |
262 | devfreq->profile->get_cur_freq(devfreq->dev.parent, &cur_freq); | |
263 | else | |
264 | cur_freq = devfreq->previous_freq; | |
265 | ||
266 | freqs.old = cur_freq; | |
267 | freqs.new = freq; | |
268 | devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); | |
269 | ||
ab5f299f | 270 | err = devfreq->profile->target(devfreq->dev.parent, &freq, flags); |
0d37189e CC |
271 | if (err) { |
272 | freqs.new = cur_freq; | |
273 | devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); | |
a3c98b8b | 274 | return err; |
0d37189e | 275 | } |
a3c98b8b | 276 | |
0fe3a664 CC |
277 | freqs.new = freq; |
278 | devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); | |
279 | ||
e552bbaf JL |
280 | if (devfreq->profile->freq_table) |
281 | if (devfreq_update_status(devfreq, freq)) | |
282 | dev_err(&devfreq->dev, | |
283 | "Couldn't update frequency transition information.\n"); | |
284 | ||
a3c98b8b MH |
285 | devfreq->previous_freq = freq; |
286 | return err; | |
287 | } | |
2df5021f | 288 | EXPORT_SYMBOL(update_devfreq); |
a3c98b8b | 289 | |
7e6fdd4b RV |
290 | /** |
291 | * devfreq_monitor() - Periodically poll devfreq objects. | |
292 | * @work: the work struct used to run devfreq_monitor periodically. | |
293 | * | |
294 | */ | |
295 | static void devfreq_monitor(struct work_struct *work) | |
296 | { | |
297 | int err; | |
298 | struct devfreq *devfreq = container_of(work, | |
299 | struct devfreq, work.work); | |
300 | ||
301 | mutex_lock(&devfreq->lock); | |
302 | err = update_devfreq(devfreq); | |
303 | if (err) | |
304 | dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err); | |
305 | ||
306 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
307 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
308 | mutex_unlock(&devfreq->lock); | |
309 | } | |
310 | ||
311 | /** | |
312 | * devfreq_monitor_start() - Start load monitoring of devfreq instance | |
313 | * @devfreq: the devfreq instance. | |
314 | * | |
315 | * Helper function for starting devfreq device load monitoing. By | |
316 | * default delayed work based monitoring is supported. Function | |
317 | * to be called from governor in response to DEVFREQ_GOV_START | |
318 | * event when device is added to devfreq framework. | |
319 | */ | |
320 | void devfreq_monitor_start(struct devfreq *devfreq) | |
321 | { | |
322 | INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); | |
323 | if (devfreq->profile->polling_ms) | |
324 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
325 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
326 | } | |
6dcdd8e3 | 327 | EXPORT_SYMBOL(devfreq_monitor_start); |
7e6fdd4b RV |
328 | |
329 | /** | |
330 | * devfreq_monitor_stop() - Stop load monitoring of a devfreq instance | |
331 | * @devfreq: the devfreq instance. | |
332 | * | |
333 | * Helper function to stop devfreq device load monitoing. Function | |
334 | * to be called from governor in response to DEVFREQ_GOV_STOP | |
335 | * event when device is removed from devfreq framework. | |
336 | */ | |
337 | void devfreq_monitor_stop(struct devfreq *devfreq) | |
338 | { | |
339 | cancel_delayed_work_sync(&devfreq->work); | |
340 | } | |
6dcdd8e3 | 341 | EXPORT_SYMBOL(devfreq_monitor_stop); |
7e6fdd4b RV |
342 | |
343 | /** | |
344 | * devfreq_monitor_suspend() - Suspend load monitoring of a devfreq instance | |
345 | * @devfreq: the devfreq instance. | |
346 | * | |
347 | * Helper function to suspend devfreq device load monitoing. Function | |
348 | * to be called from governor in response to DEVFREQ_GOV_SUSPEND | |
349 | * event or when polling interval is set to zero. | |
350 | * | |
351 | * Note: Though this function is same as devfreq_monitor_stop(), | |
352 | * intentionally kept separate to provide hooks for collecting | |
353 | * transition statistics. | |
354 | */ | |
355 | void devfreq_monitor_suspend(struct devfreq *devfreq) | |
356 | { | |
357 | mutex_lock(&devfreq->lock); | |
358 | if (devfreq->stop_polling) { | |
359 | mutex_unlock(&devfreq->lock); | |
360 | return; | |
361 | } | |
362 | ||
39688ce6 | 363 | devfreq_update_status(devfreq, devfreq->previous_freq); |
7e6fdd4b RV |
364 | devfreq->stop_polling = true; |
365 | mutex_unlock(&devfreq->lock); | |
366 | cancel_delayed_work_sync(&devfreq->work); | |
367 | } | |
6dcdd8e3 | 368 | EXPORT_SYMBOL(devfreq_monitor_suspend); |
7e6fdd4b RV |
369 | |
370 | /** | |
371 | * devfreq_monitor_resume() - Resume load monitoring of a devfreq instance | |
372 | * @devfreq: the devfreq instance. | |
373 | * | |
374 | * Helper function to resume devfreq device load monitoing. Function | |
375 | * to be called from governor in response to DEVFREQ_GOV_RESUME | |
376 | * event or when polling interval is set to non-zero. | |
377 | */ | |
378 | void devfreq_monitor_resume(struct devfreq *devfreq) | |
379 | { | |
39688ce6 RV |
380 | unsigned long freq; |
381 | ||
7e6fdd4b RV |
382 | mutex_lock(&devfreq->lock); |
383 | if (!devfreq->stop_polling) | |
384 | goto out; | |
385 | ||
386 | if (!delayed_work_pending(&devfreq->work) && | |
387 | devfreq->profile->polling_ms) | |
388 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
389 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
39688ce6 RV |
390 | |
391 | devfreq->last_stat_updated = jiffies; | |
7e6fdd4b RV |
392 | devfreq->stop_polling = false; |
393 | ||
39688ce6 RV |
394 | if (devfreq->profile->get_cur_freq && |
395 | !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) | |
396 | devfreq->previous_freq = freq; | |
397 | ||
7e6fdd4b RV |
398 | out: |
399 | mutex_unlock(&devfreq->lock); | |
400 | } | |
6dcdd8e3 | 401 | EXPORT_SYMBOL(devfreq_monitor_resume); |
7e6fdd4b RV |
402 | |
403 | /** | |
404 | * devfreq_interval_update() - Update device devfreq monitoring interval | |
405 | * @devfreq: the devfreq instance. | |
406 | * @delay: new polling interval to be set. | |
407 | * | |
408 | * Helper function to set new load monitoring polling interval. Function | |
409 | * to be called from governor in response to DEVFREQ_GOV_INTERVAL event. | |
410 | */ | |
411 | void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) | |
412 | { | |
413 | unsigned int cur_delay = devfreq->profile->polling_ms; | |
414 | unsigned int new_delay = *delay; | |
415 | ||
416 | mutex_lock(&devfreq->lock); | |
417 | devfreq->profile->polling_ms = new_delay; | |
418 | ||
419 | if (devfreq->stop_polling) | |
420 | goto out; | |
421 | ||
422 | /* if new delay is zero, stop polling */ | |
423 | if (!new_delay) { | |
424 | mutex_unlock(&devfreq->lock); | |
425 | cancel_delayed_work_sync(&devfreq->work); | |
426 | return; | |
427 | } | |
428 | ||
429 | /* if current delay is zero, start polling with new delay */ | |
430 | if (!cur_delay) { | |
431 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
432 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
433 | goto out; | |
434 | } | |
435 | ||
436 | /* if current delay is greater than new delay, restart polling */ | |
437 | if (cur_delay > new_delay) { | |
438 | mutex_unlock(&devfreq->lock); | |
439 | cancel_delayed_work_sync(&devfreq->work); | |
440 | mutex_lock(&devfreq->lock); | |
441 | if (!devfreq->stop_polling) | |
442 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
443 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
444 | } | |
445 | out: | |
446 | mutex_unlock(&devfreq->lock); | |
447 | } | |
6dcdd8e3 | 448 | EXPORT_SYMBOL(devfreq_interval_update); |
a3c98b8b MH |
449 | |
450 | /** | |
451 | * devfreq_notifier_call() - Notify that the device frequency requirements | |
452 | * has been changed out of devfreq framework. | |
c5b4a1c1 NM |
453 | * @nb: the notifier_block (supposed to be devfreq->nb) |
454 | * @type: not used | |
455 | * @devp: not used | |
a3c98b8b MH |
456 | * |
457 | * Called by a notifier that uses devfreq->nb. | |
458 | */ | |
459 | static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, | |
460 | void *devp) | |
461 | { | |
462 | struct devfreq *devfreq = container_of(nb, struct devfreq, nb); | |
463 | int ret; | |
464 | ||
465 | mutex_lock(&devfreq->lock); | |
466 | ret = update_devfreq(devfreq); | |
467 | mutex_unlock(&devfreq->lock); | |
468 | ||
469 | return ret; | |
470 | } | |
471 | ||
472 | /** | |
7e6fdd4b | 473 | * _remove_devfreq() - Remove devfreq from the list and release its resources. |
a3c98b8b | 474 | * @devfreq: the devfreq struct |
a3c98b8b | 475 | */ |
585fc83e | 476 | static void _remove_devfreq(struct devfreq *devfreq) |
a3c98b8b | 477 | { |
7e6fdd4b RV |
478 | mutex_lock(&devfreq_list_lock); |
479 | if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { | |
480 | mutex_unlock(&devfreq_list_lock); | |
481 | dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n"); | |
a3c98b8b MH |
482 | return; |
483 | } | |
7e6fdd4b RV |
484 | list_del(&devfreq->node); |
485 | mutex_unlock(&devfreq_list_lock); | |
a3c98b8b | 486 | |
1b5c1be2 NM |
487 | if (devfreq->governor) |
488 | devfreq->governor->event_handler(devfreq, | |
489 | DEVFREQ_GOV_STOP, NULL); | |
a3c98b8b MH |
490 | |
491 | if (devfreq->profile->exit) | |
492 | devfreq->profile->exit(devfreq->dev.parent); | |
493 | ||
a3c98b8b | 494 | mutex_destroy(&devfreq->lock); |
a3c98b8b MH |
495 | kfree(devfreq); |
496 | } | |
497 | ||
498 | /** | |
499 | * devfreq_dev_release() - Callback for struct device to release the device. | |
500 | * @dev: the devfreq device | |
501 | * | |
502 | * This calls _remove_devfreq() if _remove_devfreq() is not called. | |
a3c98b8b MH |
503 | */ |
504 | static void devfreq_dev_release(struct device *dev) | |
505 | { | |
506 | struct devfreq *devfreq = to_devfreq(dev); | |
a3c98b8b | 507 | |
585fc83e | 508 | _remove_devfreq(devfreq); |
a3c98b8b MH |
509 | } |
510 | ||
511 | /** | |
512 | * devfreq_add_device() - Add devfreq feature to the device | |
513 | * @dev: the device to add devfreq feature. | |
514 | * @profile: device-specific profile to run devfreq. | |
1b5c1be2 | 515 | * @governor_name: name of the policy to choose frequency. |
a3c98b8b MH |
516 | * @data: private data for the governor. The devfreq framework does not |
517 | * touch this value. | |
518 | */ | |
519 | struct devfreq *devfreq_add_device(struct device *dev, | |
520 | struct devfreq_dev_profile *profile, | |
1b5c1be2 | 521 | const char *governor_name, |
a3c98b8b MH |
522 | void *data) |
523 | { | |
524 | struct devfreq *devfreq; | |
1b5c1be2 | 525 | struct devfreq_governor *governor; |
a3c98b8b MH |
526 | int err = 0; |
527 | ||
1b5c1be2 | 528 | if (!dev || !profile || !governor_name) { |
a3c98b8b MH |
529 | dev_err(dev, "%s: Invalid parameters.\n", __func__); |
530 | return ERR_PTR(-EINVAL); | |
531 | } | |
532 | ||
7e6fdd4b RV |
533 | mutex_lock(&devfreq_list_lock); |
534 | devfreq = find_device_devfreq(dev); | |
535 | mutex_unlock(&devfreq_list_lock); | |
536 | if (!IS_ERR(devfreq)) { | |
537 | dev_err(dev, "%s: Unable to create devfreq for the device. It already has one.\n", __func__); | |
538 | err = -EINVAL; | |
539 | goto err_out; | |
a3c98b8b MH |
540 | } |
541 | ||
542 | devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); | |
543 | if (!devfreq) { | |
544 | dev_err(dev, "%s: Unable to create devfreq for the device\n", | |
545 | __func__); | |
546 | err = -ENOMEM; | |
3f19f08a | 547 | goto err_out; |
a3c98b8b MH |
548 | } |
549 | ||
550 | mutex_init(&devfreq->lock); | |
551 | mutex_lock(&devfreq->lock); | |
552 | devfreq->dev.parent = dev; | |
553 | devfreq->dev.class = devfreq_class; | |
554 | devfreq->dev.release = devfreq_dev_release; | |
555 | devfreq->profile = profile; | |
1b5c1be2 | 556 | strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); |
a3c98b8b | 557 | devfreq->previous_freq = profile->initial_freq; |
8d39fc08 | 558 | devfreq->last_status.current_frequency = profile->initial_freq; |
a3c98b8b | 559 | devfreq->data = data; |
a3c98b8b MH |
560 | devfreq->nb.notifier_call = devfreq_notifier_call; |
561 | ||
0ec09ac2 CC |
562 | if (!devfreq->profile->max_state && !devfreq->profile->freq_table) { |
563 | mutex_unlock(&devfreq->lock); | |
564 | devfreq_set_freq_table(devfreq); | |
565 | mutex_lock(&devfreq->lock); | |
566 | } | |
567 | ||
02aa2a37 | 568 | dev_set_name(&devfreq->dev, "%s", dev_name(dev)); |
a3c98b8b MH |
569 | err = device_register(&devfreq->dev); |
570 | if (err) { | |
7e6fdd4b | 571 | mutex_unlock(&devfreq->lock); |
6d3cbfa7 | 572 | goto err_out; |
a3c98b8b MH |
573 | } |
574 | ||
3e1d7fb0 MH |
575 | devfreq->trans_table = devm_kzalloc(&devfreq->dev, sizeof(unsigned int) * |
576 | devfreq->profile->max_state * | |
577 | devfreq->profile->max_state, | |
578 | GFP_KERNEL); | |
579 | devfreq->time_in_state = devm_kzalloc(&devfreq->dev, sizeof(unsigned long) * | |
580 | devfreq->profile->max_state, | |
581 | GFP_KERNEL); | |
582 | devfreq->last_stat_updated = jiffies; | |
583 | ||
0fe3a664 CC |
584 | srcu_init_notifier_head(&devfreq->transition_notifier_list); |
585 | ||
a3c98b8b MH |
586 | mutex_unlock(&devfreq->lock); |
587 | ||
a3c98b8b | 588 | mutex_lock(&devfreq_list_lock); |
a3c98b8b MH |
589 | list_add(&devfreq->node, &devfreq_list); |
590 | ||
1b5c1be2 NM |
591 | governor = find_devfreq_governor(devfreq->governor_name); |
592 | if (!IS_ERR(governor)) | |
593 | devfreq->governor = governor; | |
594 | if (devfreq->governor) | |
595 | err = devfreq->governor->event_handler(devfreq, | |
596 | DEVFREQ_GOV_START, NULL); | |
a3c98b8b | 597 | mutex_unlock(&devfreq_list_lock); |
7e6fdd4b RV |
598 | if (err) { |
599 | dev_err(dev, "%s: Unable to start governor for the device\n", | |
600 | __func__); | |
601 | goto err_init; | |
a3c98b8b | 602 | } |
7e6fdd4b | 603 | |
3f19f08a AL |
604 | return devfreq; |
605 | ||
a3c98b8b | 606 | err_init: |
7e6fdd4b | 607 | list_del(&devfreq->node); |
a3c98b8b | 608 | device_unregister(&devfreq->dev); |
3f19f08a AL |
609 | err_out: |
610 | return ERR_PTR(err); | |
a3c98b8b | 611 | } |
7e6fdd4b | 612 | EXPORT_SYMBOL(devfreq_add_device); |
a3c98b8b MH |
613 | |
614 | /** | |
615 | * devfreq_remove_device() - Remove devfreq feature from a device. | |
c5b4a1c1 | 616 | * @devfreq: the devfreq instance to be removed |
de9c7394 MH |
617 | * |
618 | * The opposite of devfreq_add_device(). | |
a3c98b8b MH |
619 | */ |
620 | int devfreq_remove_device(struct devfreq *devfreq) | |
621 | { | |
622 | if (!devfreq) | |
623 | return -EINVAL; | |
624 | ||
585fc83e | 625 | device_unregister(&devfreq->dev); |
9f3bdd4f | 626 | |
a3c98b8b MH |
627 | return 0; |
628 | } | |
7e6fdd4b | 629 | EXPORT_SYMBOL(devfreq_remove_device); |
a3c98b8b | 630 | |
8cd84092 CC |
631 | static int devm_devfreq_dev_match(struct device *dev, void *res, void *data) |
632 | { | |
633 | struct devfreq **r = res; | |
634 | ||
635 | if (WARN_ON(!r || !*r)) | |
636 | return 0; | |
637 | ||
638 | return *r == data; | |
639 | } | |
640 | ||
641 | static void devm_devfreq_dev_release(struct device *dev, void *res) | |
642 | { | |
643 | devfreq_remove_device(*(struct devfreq **)res); | |
644 | } | |
645 | ||
646 | /** | |
647 | * devm_devfreq_add_device() - Resource-managed devfreq_add_device() | |
648 | * @dev: the device to add devfreq feature. | |
649 | * @profile: device-specific profile to run devfreq. | |
650 | * @governor_name: name of the policy to choose frequency. | |
651 | * @data: private data for the governor. The devfreq framework does not | |
652 | * touch this value. | |
653 | * | |
654 | * This function manages automatically the memory of devfreq device using device | |
655 | * resource management and simplify the free operation for memory of devfreq | |
656 | * device. | |
657 | */ | |
658 | struct devfreq *devm_devfreq_add_device(struct device *dev, | |
659 | struct devfreq_dev_profile *profile, | |
660 | const char *governor_name, | |
661 | void *data) | |
662 | { | |
663 | struct devfreq **ptr, *devfreq; | |
664 | ||
665 | ptr = devres_alloc(devm_devfreq_dev_release, sizeof(*ptr), GFP_KERNEL); | |
666 | if (!ptr) | |
667 | return ERR_PTR(-ENOMEM); | |
668 | ||
669 | devfreq = devfreq_add_device(dev, profile, governor_name, data); | |
670 | if (IS_ERR(devfreq)) { | |
671 | devres_free(ptr); | |
672 | return ERR_PTR(-ENOMEM); | |
673 | } | |
674 | ||
675 | *ptr = devfreq; | |
676 | devres_add(dev, ptr); | |
677 | ||
678 | return devfreq; | |
679 | } | |
680 | EXPORT_SYMBOL(devm_devfreq_add_device); | |
681 | ||
8f510aeb CC |
682 | #ifdef CONFIG_OF |
683 | /* | |
684 | * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree | |
685 | * @dev - instance to the given device | |
686 | * @index - index into list of devfreq | |
687 | * | |
688 | * return the instance of devfreq device | |
689 | */ | |
690 | struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) | |
691 | { | |
692 | struct device_node *node; | |
693 | struct devfreq *devfreq; | |
694 | ||
695 | if (!dev) | |
696 | return ERR_PTR(-EINVAL); | |
697 | ||
698 | if (!dev->of_node) | |
699 | return ERR_PTR(-EINVAL); | |
700 | ||
701 | node = of_parse_phandle(dev->of_node, "devfreq", index); | |
702 | if (!node) | |
703 | return ERR_PTR(-ENODEV); | |
704 | ||
705 | mutex_lock(&devfreq_list_lock); | |
706 | list_for_each_entry(devfreq, &devfreq_list, node) { | |
707 | if (devfreq->dev.parent | |
708 | && devfreq->dev.parent->of_node == node) { | |
709 | mutex_unlock(&devfreq_list_lock); | |
710 | return devfreq; | |
711 | } | |
712 | } | |
713 | mutex_unlock(&devfreq_list_lock); | |
714 | ||
715 | return ERR_PTR(-EPROBE_DEFER); | |
716 | } | |
717 | #else | |
718 | struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) | |
719 | { | |
720 | return ERR_PTR(-ENODEV); | |
721 | } | |
722 | #endif /* CONFIG_OF */ | |
723 | EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle); | |
724 | ||
8cd84092 CC |
725 | /** |
726 | * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device() | |
727 | * @dev: the device to add devfreq feature. | |
728 | * @devfreq: the devfreq instance to be removed | |
729 | */ | |
730 | void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq) | |
731 | { | |
732 | WARN_ON(devres_release(dev, devm_devfreq_dev_release, | |
733 | devm_devfreq_dev_match, devfreq)); | |
734 | } | |
735 | EXPORT_SYMBOL(devm_devfreq_remove_device); | |
736 | ||
206c30cf RV |
737 | /** |
738 | * devfreq_suspend_device() - Suspend devfreq of a device. | |
739 | * @devfreq: the devfreq instance to be suspended | |
de9c7394 MH |
740 | * |
741 | * This function is intended to be called by the pm callbacks | |
742 | * (e.g., runtime_suspend, suspend) of the device driver that | |
743 | * holds the devfreq. | |
206c30cf RV |
744 | */ |
745 | int devfreq_suspend_device(struct devfreq *devfreq) | |
746 | { | |
a3c98b8b MH |
747 | if (!devfreq) |
748 | return -EINVAL; | |
749 | ||
1b5c1be2 NM |
750 | if (!devfreq->governor) |
751 | return 0; | |
752 | ||
206c30cf RV |
753 | return devfreq->governor->event_handler(devfreq, |
754 | DEVFREQ_GOV_SUSPEND, NULL); | |
755 | } | |
756 | EXPORT_SYMBOL(devfreq_suspend_device); | |
757 | ||
758 | /** | |
759 | * devfreq_resume_device() - Resume devfreq of a device. | |
760 | * @devfreq: the devfreq instance to be resumed | |
de9c7394 MH |
761 | * |
762 | * This function is intended to be called by the pm callbacks | |
763 | * (e.g., runtime_resume, resume) of the device driver that | |
764 | * holds the devfreq. | |
206c30cf RV |
765 | */ |
766 | int devfreq_resume_device(struct devfreq *devfreq) | |
767 | { | |
768 | if (!devfreq) | |
769 | return -EINVAL; | |
770 | ||
1b5c1be2 NM |
771 | if (!devfreq->governor) |
772 | return 0; | |
773 | ||
206c30cf RV |
774 | return devfreq->governor->event_handler(devfreq, |
775 | DEVFREQ_GOV_RESUME, NULL); | |
776 | } | |
777 | EXPORT_SYMBOL(devfreq_resume_device); | |
778 | ||
3aa173b8 NM |
779 | /** |
780 | * devfreq_add_governor() - Add devfreq governor | |
781 | * @governor: the devfreq governor to be added | |
782 | */ | |
783 | int devfreq_add_governor(struct devfreq_governor *governor) | |
784 | { | |
785 | struct devfreq_governor *g; | |
1b5c1be2 | 786 | struct devfreq *devfreq; |
3aa173b8 NM |
787 | int err = 0; |
788 | ||
789 | if (!governor) { | |
790 | pr_err("%s: Invalid parameters.\n", __func__); | |
791 | return -EINVAL; | |
792 | } | |
793 | ||
794 | mutex_lock(&devfreq_list_lock); | |
795 | g = find_devfreq_governor(governor->name); | |
796 | if (!IS_ERR(g)) { | |
797 | pr_err("%s: governor %s already registered\n", __func__, | |
798 | g->name); | |
799 | err = -EINVAL; | |
800 | goto err_out; | |
801 | } | |
9f3bdd4f | 802 | |
3aa173b8 NM |
803 | list_add(&governor->node, &devfreq_governor_list); |
804 | ||
1b5c1be2 NM |
805 | list_for_each_entry(devfreq, &devfreq_list, node) { |
806 | int ret = 0; | |
807 | struct device *dev = devfreq->dev.parent; | |
808 | ||
809 | if (!strncmp(devfreq->governor_name, governor->name, | |
810 | DEVFREQ_NAME_LEN)) { | |
811 | /* The following should never occur */ | |
812 | if (devfreq->governor) { | |
813 | dev_warn(dev, | |
814 | "%s: Governor %s already present\n", | |
815 | __func__, devfreq->governor->name); | |
816 | ret = devfreq->governor->event_handler(devfreq, | |
817 | DEVFREQ_GOV_STOP, NULL); | |
818 | if (ret) { | |
819 | dev_warn(dev, | |
820 | "%s: Governor %s stop = %d\n", | |
821 | __func__, | |
822 | devfreq->governor->name, ret); | |
823 | } | |
824 | /* Fall through */ | |
825 | } | |
826 | devfreq->governor = governor; | |
827 | ret = devfreq->governor->event_handler(devfreq, | |
828 | DEVFREQ_GOV_START, NULL); | |
829 | if (ret) { | |
830 | dev_warn(dev, "%s: Governor %s start=%d\n", | |
831 | __func__, devfreq->governor->name, | |
832 | ret); | |
833 | } | |
a3c98b8b MH |
834 | } |
835 | } | |
836 | ||
3aa173b8 NM |
837 | err_out: |
838 | mutex_unlock(&devfreq_list_lock); | |
a3c98b8b | 839 | |
3aa173b8 NM |
840 | return err; |
841 | } | |
842 | EXPORT_SYMBOL(devfreq_add_governor); | |
a3c98b8b | 843 | |
3aa173b8 NM |
844 | /** |
845 | * devfreq_remove_device() - Remove devfreq feature from a device. | |
846 | * @governor: the devfreq governor to be removed | |
847 | */ | |
848 | int devfreq_remove_governor(struct devfreq_governor *governor) | |
849 | { | |
850 | struct devfreq_governor *g; | |
1b5c1be2 | 851 | struct devfreq *devfreq; |
3aa173b8 NM |
852 | int err = 0; |
853 | ||
854 | if (!governor) { | |
855 | pr_err("%s: Invalid parameters.\n", __func__); | |
856 | return -EINVAL; | |
857 | } | |
858 | ||
859 | mutex_lock(&devfreq_list_lock); | |
860 | g = find_devfreq_governor(governor->name); | |
861 | if (IS_ERR(g)) { | |
862 | pr_err("%s: governor %s not registered\n", __func__, | |
b9e1c8e8 | 863 | governor->name); |
f9c08e2a | 864 | err = PTR_ERR(g); |
3aa173b8 NM |
865 | goto err_out; |
866 | } | |
1b5c1be2 NM |
867 | list_for_each_entry(devfreq, &devfreq_list, node) { |
868 | int ret; | |
869 | struct device *dev = devfreq->dev.parent; | |
870 | ||
871 | if (!strncmp(devfreq->governor_name, governor->name, | |
872 | DEVFREQ_NAME_LEN)) { | |
873 | /* we should have a devfreq governor! */ | |
874 | if (!devfreq->governor) { | |
875 | dev_warn(dev, "%s: Governor %s NOT present\n", | |
876 | __func__, governor->name); | |
877 | continue; | |
878 | /* Fall through */ | |
879 | } | |
880 | ret = devfreq->governor->event_handler(devfreq, | |
881 | DEVFREQ_GOV_STOP, NULL); | |
882 | if (ret) { | |
883 | dev_warn(dev, "%s: Governor %s stop=%d\n", | |
884 | __func__, devfreq->governor->name, | |
885 | ret); | |
886 | } | |
887 | devfreq->governor = NULL; | |
888 | } | |
889 | } | |
3aa173b8 NM |
890 | |
891 | list_del(&governor->node); | |
892 | err_out: | |
893 | mutex_unlock(&devfreq_list_lock); | |
894 | ||
895 | return err; | |
a3c98b8b | 896 | } |
3aa173b8 | 897 | EXPORT_SYMBOL(devfreq_remove_governor); |
a3c98b8b | 898 | |
a93d6b0a | 899 | static ssize_t governor_show(struct device *dev, |
9005b650 MH |
900 | struct device_attribute *attr, char *buf) |
901 | { | |
1b5c1be2 NM |
902 | if (!to_devfreq(dev)->governor) |
903 | return -EINVAL; | |
904 | ||
9005b650 MH |
905 | return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name); |
906 | } | |
907 | ||
a93d6b0a | 908 | static ssize_t governor_store(struct device *dev, struct device_attribute *attr, |
0359d1af NM |
909 | const char *buf, size_t count) |
910 | { | |
911 | struct devfreq *df = to_devfreq(dev); | |
912 | int ret; | |
913 | char str_governor[DEVFREQ_NAME_LEN + 1]; | |
914 | struct devfreq_governor *governor; | |
915 | ||
916 | ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor); | |
917 | if (ret != 1) | |
918 | return -EINVAL; | |
919 | ||
920 | mutex_lock(&devfreq_list_lock); | |
921 | governor = find_devfreq_governor(str_governor); | |
922 | if (IS_ERR(governor)) { | |
923 | ret = PTR_ERR(governor); | |
924 | goto out; | |
925 | } | |
14a21e7b TJ |
926 | if (df->governor == governor) { |
927 | ret = 0; | |
0359d1af | 928 | goto out; |
14a21e7b | 929 | } |
0359d1af NM |
930 | |
931 | if (df->governor) { | |
932 | ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL); | |
933 | if (ret) { | |
934 | dev_warn(dev, "%s: Governor %s not stopped(%d)\n", | |
935 | __func__, df->governor->name, ret); | |
936 | goto out; | |
937 | } | |
938 | } | |
939 | df->governor = governor; | |
940 | strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN); | |
941 | ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL); | |
942 | if (ret) | |
943 | dev_warn(dev, "%s: Governor %s not started(%d)\n", | |
944 | __func__, df->governor->name, ret); | |
945 | out: | |
946 | mutex_unlock(&devfreq_list_lock); | |
947 | ||
948 | if (!ret) | |
949 | ret = count; | |
950 | return ret; | |
951 | } | |
a93d6b0a GKH |
952 | static DEVICE_ATTR_RW(governor); |
953 | ||
954 | static ssize_t available_governors_show(struct device *d, | |
955 | struct device_attribute *attr, | |
956 | char *buf) | |
50a5b33e NM |
957 | { |
958 | struct devfreq_governor *tmp_governor; | |
959 | ssize_t count = 0; | |
960 | ||
961 | mutex_lock(&devfreq_list_lock); | |
962 | list_for_each_entry(tmp_governor, &devfreq_governor_list, node) | |
963 | count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), | |
964 | "%s ", tmp_governor->name); | |
965 | mutex_unlock(&devfreq_list_lock); | |
966 | ||
967 | /* Truncate the trailing space */ | |
968 | if (count) | |
969 | count--; | |
970 | ||
971 | count += sprintf(&buf[count], "\n"); | |
972 | ||
973 | return count; | |
974 | } | |
a93d6b0a | 975 | static DEVICE_ATTR_RO(available_governors); |
0359d1af | 976 | |
a93d6b0a GKH |
977 | static ssize_t cur_freq_show(struct device *dev, struct device_attribute *attr, |
978 | char *buf) | |
7f98a905 RV |
979 | { |
980 | unsigned long freq; | |
981 | struct devfreq *devfreq = to_devfreq(dev); | |
982 | ||
983 | if (devfreq->profile->get_cur_freq && | |
984 | !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) | |
985 | return sprintf(buf, "%lu\n", freq); | |
986 | ||
987 | return sprintf(buf, "%lu\n", devfreq->previous_freq); | |
988 | } | |
a93d6b0a | 989 | static DEVICE_ATTR_RO(cur_freq); |
7f98a905 | 990 | |
a93d6b0a GKH |
991 | static ssize_t target_freq_show(struct device *dev, |
992 | struct device_attribute *attr, char *buf) | |
9005b650 MH |
993 | { |
994 | return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq); | |
995 | } | |
a93d6b0a | 996 | static DEVICE_ATTR_RO(target_freq); |
9005b650 | 997 | |
a93d6b0a | 998 | static ssize_t polling_interval_show(struct device *dev, |
9005b650 MH |
999 | struct device_attribute *attr, char *buf) |
1000 | { | |
1001 | return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms); | |
1002 | } | |
1003 | ||
a93d6b0a | 1004 | static ssize_t polling_interval_store(struct device *dev, |
9005b650 MH |
1005 | struct device_attribute *attr, |
1006 | const char *buf, size_t count) | |
1007 | { | |
1008 | struct devfreq *df = to_devfreq(dev); | |
1009 | unsigned int value; | |
1010 | int ret; | |
1011 | ||
1b5c1be2 NM |
1012 | if (!df->governor) |
1013 | return -EINVAL; | |
1014 | ||
9005b650 MH |
1015 | ret = sscanf(buf, "%u", &value); |
1016 | if (ret != 1) | |
12e26265 | 1017 | return -EINVAL; |
9005b650 | 1018 | |
7e6fdd4b | 1019 | df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL, &value); |
9005b650 MH |
1020 | ret = count; |
1021 | ||
9005b650 MH |
1022 | return ret; |
1023 | } | |
a93d6b0a | 1024 | static DEVICE_ATTR_RW(polling_interval); |
9005b650 | 1025 | |
a93d6b0a | 1026 | static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, |
6530b9de MH |
1027 | const char *buf, size_t count) |
1028 | { | |
1029 | struct devfreq *df = to_devfreq(dev); | |
1030 | unsigned long value; | |
1031 | int ret; | |
1032 | unsigned long max; | |
1033 | ||
1034 | ret = sscanf(buf, "%lu", &value); | |
1035 | if (ret != 1) | |
12e26265 | 1036 | return -EINVAL; |
6530b9de MH |
1037 | |
1038 | mutex_lock(&df->lock); | |
1039 | max = df->max_freq; | |
1040 | if (value && max && value > max) { | |
1041 | ret = -EINVAL; | |
1042 | goto unlock; | |
1043 | } | |
1044 | ||
1045 | df->min_freq = value; | |
1046 | update_devfreq(df); | |
1047 | ret = count; | |
1048 | unlock: | |
1049 | mutex_unlock(&df->lock); | |
6530b9de MH |
1050 | return ret; |
1051 | } | |
1052 | ||
a93d6b0a | 1053 | static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, |
6530b9de MH |
1054 | const char *buf, size_t count) |
1055 | { | |
1056 | struct devfreq *df = to_devfreq(dev); | |
1057 | unsigned long value; | |
1058 | int ret; | |
1059 | unsigned long min; | |
1060 | ||
1061 | ret = sscanf(buf, "%lu", &value); | |
1062 | if (ret != 1) | |
12e26265 | 1063 | return -EINVAL; |
6530b9de MH |
1064 | |
1065 | mutex_lock(&df->lock); | |
1066 | min = df->min_freq; | |
1067 | if (value && min && value < min) { | |
1068 | ret = -EINVAL; | |
1069 | goto unlock; | |
1070 | } | |
1071 | ||
1072 | df->max_freq = value; | |
1073 | update_devfreq(df); | |
1074 | ret = count; | |
1075 | unlock: | |
1076 | mutex_unlock(&df->lock); | |
6530b9de MH |
1077 | return ret; |
1078 | } | |
1079 | ||
3104fa30 CC |
1080 | #define show_one(name) \ |
1081 | static ssize_t name##_show \ | |
1082 | (struct device *dev, struct device_attribute *attr, char *buf) \ | |
1083 | { \ | |
1084 | return sprintf(buf, "%lu\n", to_devfreq(dev)->name); \ | |
6530b9de | 1085 | } |
3104fa30 CC |
1086 | show_one(min_freq); |
1087 | show_one(max_freq); | |
1088 | ||
1089 | static DEVICE_ATTR_RW(min_freq); | |
a93d6b0a | 1090 | static DEVICE_ATTR_RW(max_freq); |
6530b9de | 1091 | |
a93d6b0a GKH |
1092 | static ssize_t available_frequencies_show(struct device *d, |
1093 | struct device_attribute *attr, | |
1094 | char *buf) | |
d287de85 NM |
1095 | { |
1096 | struct devfreq *df = to_devfreq(d); | |
1097 | struct device *dev = df->dev.parent; | |
47d43ba7 | 1098 | struct dev_pm_opp *opp; |
d287de85 NM |
1099 | ssize_t count = 0; |
1100 | unsigned long freq = 0; | |
1101 | ||
1102 | rcu_read_lock(); | |
1103 | do { | |
5d4879cd | 1104 | opp = dev_pm_opp_find_freq_ceil(dev, &freq); |
d287de85 NM |
1105 | if (IS_ERR(opp)) |
1106 | break; | |
1107 | ||
1108 | count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), | |
1109 | "%lu ", freq); | |
1110 | freq++; | |
1111 | } while (1); | |
1112 | rcu_read_unlock(); | |
1113 | ||
1114 | /* Truncate the trailing space */ | |
1115 | if (count) | |
1116 | count--; | |
1117 | ||
1118 | count += sprintf(&buf[count], "\n"); | |
1119 | ||
1120 | return count; | |
1121 | } | |
a93d6b0a | 1122 | static DEVICE_ATTR_RO(available_frequencies); |
d287de85 | 1123 | |
a93d6b0a GKH |
1124 | static ssize_t trans_stat_show(struct device *dev, |
1125 | struct device_attribute *attr, char *buf) | |
e552bbaf JL |
1126 | { |
1127 | struct devfreq *devfreq = to_devfreq(dev); | |
1128 | ssize_t len; | |
39688ce6 | 1129 | int i, j; |
e552bbaf JL |
1130 | unsigned int max_state = devfreq->profile->max_state; |
1131 | ||
39688ce6 RV |
1132 | if (!devfreq->stop_polling && |
1133 | devfreq_update_status(devfreq, devfreq->previous_freq)) | |
e552bbaf | 1134 | return 0; |
34bd3220 MH |
1135 | if (max_state == 0) |
1136 | return sprintf(buf, "Not Supported.\n"); | |
e552bbaf | 1137 | |
d7df1e46 CC |
1138 | len = sprintf(buf, " From : To\n"); |
1139 | len += sprintf(buf + len, " :"); | |
e552bbaf | 1140 | for (i = 0; i < max_state; i++) |
d7df1e46 | 1141 | len += sprintf(buf + len, "%10lu", |
e552bbaf JL |
1142 | devfreq->profile->freq_table[i]); |
1143 | ||
1144 | len += sprintf(buf + len, " time(ms)\n"); | |
1145 | ||
1146 | for (i = 0; i < max_state; i++) { | |
1147 | if (devfreq->profile->freq_table[i] | |
1148 | == devfreq->previous_freq) { | |
1149 | len += sprintf(buf + len, "*"); | |
1150 | } else { | |
1151 | len += sprintf(buf + len, " "); | |
1152 | } | |
d7df1e46 | 1153 | len += sprintf(buf + len, "%10lu:", |
e552bbaf JL |
1154 | devfreq->profile->freq_table[i]); |
1155 | for (j = 0; j < max_state; j++) | |
d7df1e46 | 1156 | len += sprintf(buf + len, "%10u", |
e552bbaf JL |
1157 | devfreq->trans_table[(i * max_state) + j]); |
1158 | len += sprintf(buf + len, "%10u\n", | |
1159 | jiffies_to_msecs(devfreq->time_in_state[i])); | |
1160 | } | |
1161 | ||
1162 | len += sprintf(buf + len, "Total transition : %u\n", | |
1163 | devfreq->total_trans); | |
1164 | return len; | |
1165 | } | |
a93d6b0a GKH |
1166 | static DEVICE_ATTR_RO(trans_stat); |
1167 | ||
1168 | static struct attribute *devfreq_attrs[] = { | |
1169 | &dev_attr_governor.attr, | |
1170 | &dev_attr_available_governors.attr, | |
1171 | &dev_attr_cur_freq.attr, | |
1172 | &dev_attr_available_frequencies.attr, | |
1173 | &dev_attr_target_freq.attr, | |
1174 | &dev_attr_polling_interval.attr, | |
1175 | &dev_attr_min_freq.attr, | |
1176 | &dev_attr_max_freq.attr, | |
1177 | &dev_attr_trans_stat.attr, | |
1178 | NULL, | |
9005b650 | 1179 | }; |
a93d6b0a | 1180 | ATTRIBUTE_GROUPS(devfreq); |
9005b650 | 1181 | |
a3c98b8b MH |
1182 | static int __init devfreq_init(void) |
1183 | { | |
1184 | devfreq_class = class_create(THIS_MODULE, "devfreq"); | |
1185 | if (IS_ERR(devfreq_class)) { | |
1186 | pr_err("%s: couldn't create class\n", __FILE__); | |
1187 | return PTR_ERR(devfreq_class); | |
1188 | } | |
7e6fdd4b RV |
1189 | |
1190 | devfreq_wq = create_freezable_workqueue("devfreq_wq"); | |
ea7f4548 | 1191 | if (!devfreq_wq) { |
7e6fdd4b RV |
1192 | class_destroy(devfreq_class); |
1193 | pr_err("%s: couldn't create workqueue\n", __FILE__); | |
ea7f4548 | 1194 | return -ENOMEM; |
7e6fdd4b | 1195 | } |
a93d6b0a | 1196 | devfreq_class->dev_groups = devfreq_groups; |
7e6fdd4b | 1197 | |
a3c98b8b MH |
1198 | return 0; |
1199 | } | |
1200 | subsys_initcall(devfreq_init); | |
1201 | ||
1202 | static void __exit devfreq_exit(void) | |
1203 | { | |
1204 | class_destroy(devfreq_class); | |
7e6fdd4b | 1205 | destroy_workqueue(devfreq_wq); |
a3c98b8b MH |
1206 | } |
1207 | module_exit(devfreq_exit); | |
1208 | ||
1209 | /* | |
1210 | * The followings are helper functions for devfreq user device drivers with | |
1211 | * OPP framework. | |
1212 | */ | |
1213 | ||
1214 | /** | |
1215 | * devfreq_recommended_opp() - Helper function to get proper OPP for the | |
1216 | * freq value given to target callback. | |
c5b4a1c1 NM |
1217 | * @dev: The devfreq user device. (parent of devfreq) |
1218 | * @freq: The frequency given to target function | |
1219 | * @flags: Flags handed from devfreq framework. | |
a3c98b8b | 1220 | * |
bcb27549 NM |
1221 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
1222 | * protected pointer. The reason for the same is that the opp pointer which is | |
1223 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
1224 | * under the locked area. The pointer returned must be used prior to unlocking | |
1225 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
a3c98b8b | 1226 | */ |
47d43ba7 NM |
1227 | struct dev_pm_opp *devfreq_recommended_opp(struct device *dev, |
1228 | unsigned long *freq, | |
1229 | u32 flags) | |
a3c98b8b | 1230 | { |
47d43ba7 | 1231 | struct dev_pm_opp *opp; |
a3c98b8b | 1232 | |
ab5f299f MH |
1233 | if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) { |
1234 | /* The freq is an upper bound. opp should be lower */ | |
5d4879cd | 1235 | opp = dev_pm_opp_find_freq_floor(dev, freq); |
ab5f299f MH |
1236 | |
1237 | /* If not available, use the closest opp */ | |
0779726c | 1238 | if (opp == ERR_PTR(-ERANGE)) |
5d4879cd | 1239 | opp = dev_pm_opp_find_freq_ceil(dev, freq); |
ab5f299f MH |
1240 | } else { |
1241 | /* The freq is an lower bound. opp should be higher */ | |
5d4879cd | 1242 | opp = dev_pm_opp_find_freq_ceil(dev, freq); |
ab5f299f MH |
1243 | |
1244 | /* If not available, use the closest opp */ | |
0779726c | 1245 | if (opp == ERR_PTR(-ERANGE)) |
5d4879cd | 1246 | opp = dev_pm_opp_find_freq_floor(dev, freq); |
ab5f299f MH |
1247 | } |
1248 | ||
a3c98b8b MH |
1249 | return opp; |
1250 | } | |
bd7e9277 | 1251 | EXPORT_SYMBOL(devfreq_recommended_opp); |
a3c98b8b MH |
1252 | |
1253 | /** | |
1254 | * devfreq_register_opp_notifier() - Helper function to get devfreq notified | |
1255 | * for any changes in the OPP availability | |
1256 | * changes | |
c5b4a1c1 NM |
1257 | * @dev: The devfreq user device. (parent of devfreq) |
1258 | * @devfreq: The devfreq object. | |
a3c98b8b MH |
1259 | */ |
1260 | int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) | |
1261 | { | |
389baed0 MH |
1262 | struct srcu_notifier_head *nh; |
1263 | int ret = 0; | |
a3c98b8b | 1264 | |
389baed0 | 1265 | rcu_read_lock(); |
5d4879cd | 1266 | nh = dev_pm_opp_get_notifier(dev); |
a3c98b8b | 1267 | if (IS_ERR(nh)) |
389baed0 MH |
1268 | ret = PTR_ERR(nh); |
1269 | rcu_read_unlock(); | |
1270 | if (!ret) | |
1271 | ret = srcu_notifier_chain_register(nh, &devfreq->nb); | |
1272 | ||
1273 | return ret; | |
a3c98b8b | 1274 | } |
bd7e9277 | 1275 | EXPORT_SYMBOL(devfreq_register_opp_notifier); |
a3c98b8b MH |
1276 | |
1277 | /** | |
1278 | * devfreq_unregister_opp_notifier() - Helper function to stop getting devfreq | |
1279 | * notified for any changes in the OPP | |
1280 | * availability changes anymore. | |
c5b4a1c1 NM |
1281 | * @dev: The devfreq user device. (parent of devfreq) |
1282 | * @devfreq: The devfreq object. | |
a3c98b8b MH |
1283 | * |
1284 | * At exit() callback of devfreq_dev_profile, this must be included if | |
1285 | * devfreq_recommended_opp is used. | |
1286 | */ | |
1287 | int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) | |
1288 | { | |
389baed0 MH |
1289 | struct srcu_notifier_head *nh; |
1290 | int ret = 0; | |
a3c98b8b | 1291 | |
389baed0 | 1292 | rcu_read_lock(); |
5d4879cd | 1293 | nh = dev_pm_opp_get_notifier(dev); |
a3c98b8b | 1294 | if (IS_ERR(nh)) |
389baed0 MH |
1295 | ret = PTR_ERR(nh); |
1296 | rcu_read_unlock(); | |
1297 | if (!ret) | |
1298 | ret = srcu_notifier_chain_unregister(nh, &devfreq->nb); | |
1299 | ||
1300 | return ret; | |
a3c98b8b | 1301 | } |
bd7e9277 | 1302 | EXPORT_SYMBOL(devfreq_unregister_opp_notifier); |
a3c98b8b | 1303 | |
d5b040d0 CC |
1304 | static void devm_devfreq_opp_release(struct device *dev, void *res) |
1305 | { | |
1306 | devfreq_unregister_opp_notifier(dev, *(struct devfreq **)res); | |
1307 | } | |
1308 | ||
1309 | /** | |
1310 | * devm_ devfreq_register_opp_notifier() | |
1311 | * - Resource-managed devfreq_register_opp_notifier() | |
1312 | * @dev: The devfreq user device. (parent of devfreq) | |
1313 | * @devfreq: The devfreq object. | |
1314 | */ | |
1315 | int devm_devfreq_register_opp_notifier(struct device *dev, | |
1316 | struct devfreq *devfreq) | |
1317 | { | |
1318 | struct devfreq **ptr; | |
1319 | int ret; | |
1320 | ||
1321 | ptr = devres_alloc(devm_devfreq_opp_release, sizeof(*ptr), GFP_KERNEL); | |
1322 | if (!ptr) | |
1323 | return -ENOMEM; | |
1324 | ||
1325 | ret = devfreq_register_opp_notifier(dev, devfreq); | |
1326 | if (ret) { | |
1327 | devres_free(ptr); | |
1328 | return ret; | |
1329 | } | |
1330 | ||
1331 | *ptr = devfreq; | |
1332 | devres_add(dev, ptr); | |
1333 | ||
1334 | return 0; | |
1335 | } | |
1336 | EXPORT_SYMBOL(devm_devfreq_register_opp_notifier); | |
1337 | ||
1338 | /** | |
1339 | * devm_devfreq_unregister_opp_notifier() | |
1340 | * - Resource-managed devfreq_unregister_opp_notifier() | |
1341 | * @dev: The devfreq user device. (parent of devfreq) | |
1342 | * @devfreq: The devfreq object. | |
1343 | */ | |
1344 | void devm_devfreq_unregister_opp_notifier(struct device *dev, | |
1345 | struct devfreq *devfreq) | |
1346 | { | |
1347 | WARN_ON(devres_release(dev, devm_devfreq_opp_release, | |
1348 | devm_devfreq_dev_match, devfreq)); | |
1349 | } | |
1350 | EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier); | |
1351 | ||
0fe3a664 CC |
1352 | /** |
1353 | * devfreq_register_notifier() - Register a driver with devfreq | |
1354 | * @devfreq: The devfreq object. | |
1355 | * @nb: The notifier block to register. | |
1356 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1357 | */ | |
1358 | int devfreq_register_notifier(struct devfreq *devfreq, | |
1359 | struct notifier_block *nb, | |
1360 | unsigned int list) | |
1361 | { | |
1362 | int ret = 0; | |
1363 | ||
1364 | if (!devfreq) | |
1365 | return -EINVAL; | |
1366 | ||
1367 | switch (list) { | |
1368 | case DEVFREQ_TRANSITION_NOTIFIER: | |
1369 | ret = srcu_notifier_chain_register( | |
1370 | &devfreq->transition_notifier_list, nb); | |
1371 | break; | |
1372 | default: | |
1373 | ret = -EINVAL; | |
1374 | } | |
1375 | ||
1376 | return ret; | |
1377 | } | |
1378 | EXPORT_SYMBOL(devfreq_register_notifier); | |
1379 | ||
1380 | /* | |
1381 | * devfreq_unregister_notifier() - Unregister a driver with devfreq | |
1382 | * @devfreq: The devfreq object. | |
1383 | * @nb: The notifier block to be unregistered. | |
1384 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1385 | */ | |
1386 | int devfreq_unregister_notifier(struct devfreq *devfreq, | |
1387 | struct notifier_block *nb, | |
1388 | unsigned int list) | |
1389 | { | |
1390 | int ret = 0; | |
1391 | ||
1392 | if (!devfreq) | |
1393 | return -EINVAL; | |
1394 | ||
1395 | switch (list) { | |
1396 | case DEVFREQ_TRANSITION_NOTIFIER: | |
1397 | ret = srcu_notifier_chain_unregister( | |
1398 | &devfreq->transition_notifier_list, nb); | |
1399 | break; | |
1400 | default: | |
1401 | ret = -EINVAL; | |
1402 | } | |
1403 | ||
1404 | return ret; | |
1405 | } | |
1406 | EXPORT_SYMBOL(devfreq_unregister_notifier); | |
1407 | ||
1408 | struct devfreq_notifier_devres { | |
1409 | struct devfreq *devfreq; | |
1410 | struct notifier_block *nb; | |
1411 | unsigned int list; | |
1412 | }; | |
1413 | ||
1414 | static void devm_devfreq_notifier_release(struct device *dev, void *res) | |
1415 | { | |
1416 | struct devfreq_notifier_devres *this = res; | |
1417 | ||
1418 | devfreq_unregister_notifier(this->devfreq, this->nb, this->list); | |
1419 | } | |
1420 | ||
1421 | /** | |
1422 | * devm_devfreq_register_notifier() | |
1423 | - Resource-managed devfreq_register_notifier() | |
1424 | * @dev: The devfreq user device. (parent of devfreq) | |
1425 | * @devfreq: The devfreq object. | |
1426 | * @nb: The notifier block to be unregistered. | |
1427 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1428 | */ | |
1429 | int devm_devfreq_register_notifier(struct device *dev, | |
1430 | struct devfreq *devfreq, | |
1431 | struct notifier_block *nb, | |
1432 | unsigned int list) | |
1433 | { | |
1434 | struct devfreq_notifier_devres *ptr; | |
1435 | int ret; | |
1436 | ||
1437 | ptr = devres_alloc(devm_devfreq_notifier_release, sizeof(*ptr), | |
1438 | GFP_KERNEL); | |
1439 | if (!ptr) | |
1440 | return -ENOMEM; | |
1441 | ||
1442 | ret = devfreq_register_notifier(devfreq, nb, list); | |
1443 | if (ret) { | |
1444 | devres_free(ptr); | |
1445 | return ret; | |
1446 | } | |
1447 | ||
1448 | ptr->devfreq = devfreq; | |
1449 | ptr->nb = nb; | |
1450 | ptr->list = list; | |
1451 | devres_add(dev, ptr); | |
1452 | ||
1453 | return 0; | |
1454 | } | |
1455 | EXPORT_SYMBOL(devm_devfreq_register_notifier); | |
1456 | ||
1457 | /** | |
1458 | * devm_devfreq_unregister_notifier() | |
1459 | - Resource-managed devfreq_unregister_notifier() | |
1460 | * @dev: The devfreq user device. (parent of devfreq) | |
1461 | * @devfreq: The devfreq object. | |
1462 | * @nb: The notifier block to be unregistered. | |
1463 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1464 | */ | |
1465 | void devm_devfreq_unregister_notifier(struct device *dev, | |
1466 | struct devfreq *devfreq, | |
1467 | struct notifier_block *nb, | |
1468 | unsigned int list) | |
1469 | { | |
1470 | WARN_ON(devres_release(dev, devm_devfreq_notifier_release, | |
1471 | devm_devfreq_dev_match, devfreq)); | |
1472 | } | |
1473 | EXPORT_SYMBOL(devm_devfreq_unregister_notifier); | |
1474 | ||
a3c98b8b MH |
1475 | MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); |
1476 | MODULE_DESCRIPTION("devfreq class support"); | |
1477 | MODULE_LICENSE("GPL"); |