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> | |
417dc4bb | 18 | #include <linux/export.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 | 139 | |
d0563a03 TJ |
140 | /* Immediately exit if previous_freq is not initialized yet. */ |
141 | if (!devfreq->previous_freq) | |
142 | goto out; | |
143 | ||
e35d35a1 SK |
144 | prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq); |
145 | if (prev_lev < 0) { | |
146 | ret = prev_lev; | |
147 | goto out; | |
148 | } | |
149 | ||
150 | devfreq->time_in_state[prev_lev] += | |
e552bbaf | 151 | cur_time - devfreq->last_stat_updated; |
e35d35a1 SK |
152 | |
153 | lev = devfreq_get_freq_level(devfreq, freq); | |
154 | if (lev < 0) { | |
155 | ret = lev; | |
156 | goto out; | |
157 | } | |
158 | ||
159 | if (lev != prev_lev) { | |
e552bbaf JL |
160 | devfreq->trans_table[(prev_lev * |
161 | devfreq->profile->max_state) + lev]++; | |
162 | devfreq->total_trans++; | |
163 | } | |
e552bbaf | 164 | |
e35d35a1 SK |
165 | out: |
166 | devfreq->last_stat_updated = cur_time; | |
167 | return ret; | |
e552bbaf JL |
168 | } |
169 | ||
3aa173b8 NM |
170 | /** |
171 | * find_devfreq_governor() - find devfreq governor from name | |
172 | * @name: name of the governor | |
173 | * | |
174 | * Search the list of devfreq governors and return the matched | |
175 | * governor's pointer. devfreq_list_lock should be held by the caller. | |
176 | */ | |
177 | static struct devfreq_governor *find_devfreq_governor(const char *name) | |
178 | { | |
179 | struct devfreq_governor *tmp_governor; | |
180 | ||
9348da2f | 181 | if (IS_ERR_OR_NULL(name)) { |
3aa173b8 NM |
182 | pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); |
183 | return ERR_PTR(-EINVAL); | |
184 | } | |
185 | WARN(!mutex_is_locked(&devfreq_list_lock), | |
186 | "devfreq_list_lock must be locked."); | |
187 | ||
188 | list_for_each_entry(tmp_governor, &devfreq_governor_list, node) { | |
189 | if (!strncmp(tmp_governor->name, name, DEVFREQ_NAME_LEN)) | |
190 | return tmp_governor; | |
191 | } | |
192 | ||
193 | return ERR_PTR(-ENODEV); | |
194 | } | |
195 | ||
0fe3a664 CC |
196 | static int devfreq_notify_transition(struct devfreq *devfreq, |
197 | struct devfreq_freqs *freqs, unsigned int state) | |
198 | { | |
199 | if (!devfreq) | |
200 | return -EINVAL; | |
201 | ||
202 | switch (state) { | |
203 | case DEVFREQ_PRECHANGE: | |
204 | srcu_notifier_call_chain(&devfreq->transition_notifier_list, | |
205 | DEVFREQ_PRECHANGE, freqs); | |
206 | break; | |
207 | ||
208 | case DEVFREQ_POSTCHANGE: | |
209 | srcu_notifier_call_chain(&devfreq->transition_notifier_list, | |
210 | DEVFREQ_POSTCHANGE, freqs); | |
211 | break; | |
212 | default: | |
213 | return -EINVAL; | |
214 | } | |
215 | ||
216 | return 0; | |
217 | } | |
218 | ||
7e6fdd4b RV |
219 | /* Load monitoring helper functions for governors use */ |
220 | ||
a3c98b8b MH |
221 | /** |
222 | * update_devfreq() - Reevaluate the device and configure frequency. | |
223 | * @devfreq: the devfreq instance. | |
224 | * | |
225 | * Note: Lock devfreq->lock before calling update_devfreq | |
226 | * This function is exported for governors. | |
227 | */ | |
228 | int update_devfreq(struct devfreq *devfreq) | |
229 | { | |
0fe3a664 CC |
230 | struct devfreq_freqs freqs; |
231 | unsigned long freq, cur_freq; | |
a3c98b8b | 232 | int err = 0; |
ab5f299f | 233 | u32 flags = 0; |
a3c98b8b MH |
234 | |
235 | if (!mutex_is_locked(&devfreq->lock)) { | |
236 | WARN(true, "devfreq->lock must be locked by the caller.\n"); | |
237 | return -EINVAL; | |
238 | } | |
239 | ||
1b5c1be2 NM |
240 | if (!devfreq->governor) |
241 | return -EINVAL; | |
242 | ||
a3c98b8b MH |
243 | /* Reevaluate the proper frequency */ |
244 | err = devfreq->governor->get_target_freq(devfreq, &freq); | |
245 | if (err) | |
246 | return err; | |
247 | ||
ab5f299f | 248 | /* |
d3b7e174 | 249 | * Adjust the frequency with user freq and QoS. |
ab5f299f | 250 | * |
d3b7e174 JM |
251 | * List from the highest priority |
252 | * max_freq | |
ab5f299f MH |
253 | * min_freq |
254 | */ | |
255 | ||
256 | if (devfreq->min_freq && freq < devfreq->min_freq) { | |
257 | freq = devfreq->min_freq; | |
258 | flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */ | |
259 | } | |
260 | if (devfreq->max_freq && freq > devfreq->max_freq) { | |
261 | freq = devfreq->max_freq; | |
262 | flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ | |
263 | } | |
264 | ||
0fe3a664 CC |
265 | if (devfreq->profile->get_cur_freq) |
266 | devfreq->profile->get_cur_freq(devfreq->dev.parent, &cur_freq); | |
267 | else | |
268 | cur_freq = devfreq->previous_freq; | |
269 | ||
270 | freqs.old = cur_freq; | |
271 | freqs.new = freq; | |
272 | devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); | |
273 | ||
ab5f299f | 274 | err = devfreq->profile->target(devfreq->dev.parent, &freq, flags); |
0d37189e CC |
275 | if (err) { |
276 | freqs.new = cur_freq; | |
277 | devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); | |
a3c98b8b | 278 | return err; |
0d37189e | 279 | } |
a3c98b8b | 280 | |
0fe3a664 CC |
281 | freqs.new = freq; |
282 | devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); | |
283 | ||
e552bbaf JL |
284 | if (devfreq->profile->freq_table) |
285 | if (devfreq_update_status(devfreq, freq)) | |
286 | dev_err(&devfreq->dev, | |
287 | "Couldn't update frequency transition information.\n"); | |
288 | ||
a3c98b8b MH |
289 | devfreq->previous_freq = freq; |
290 | return err; | |
291 | } | |
2df5021f | 292 | EXPORT_SYMBOL(update_devfreq); |
a3c98b8b | 293 | |
7e6fdd4b RV |
294 | /** |
295 | * devfreq_monitor() - Periodically poll devfreq objects. | |
296 | * @work: the work struct used to run devfreq_monitor periodically. | |
297 | * | |
298 | */ | |
299 | static void devfreq_monitor(struct work_struct *work) | |
300 | { | |
301 | int err; | |
302 | struct devfreq *devfreq = container_of(work, | |
303 | struct devfreq, work.work); | |
304 | ||
305 | mutex_lock(&devfreq->lock); | |
306 | err = update_devfreq(devfreq); | |
307 | if (err) | |
308 | dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err); | |
309 | ||
310 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
311 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
312 | mutex_unlock(&devfreq->lock); | |
313 | } | |
314 | ||
315 | /** | |
316 | * devfreq_monitor_start() - Start load monitoring of devfreq instance | |
317 | * @devfreq: the devfreq instance. | |
318 | * | |
319 | * Helper function for starting devfreq device load monitoing. By | |
320 | * default delayed work based monitoring is supported. Function | |
321 | * to be called from governor in response to DEVFREQ_GOV_START | |
322 | * event when device is added to devfreq framework. | |
323 | */ | |
324 | void devfreq_monitor_start(struct devfreq *devfreq) | |
325 | { | |
326 | INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); | |
327 | if (devfreq->profile->polling_ms) | |
328 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
329 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
330 | } | |
6dcdd8e3 | 331 | EXPORT_SYMBOL(devfreq_monitor_start); |
7e6fdd4b RV |
332 | |
333 | /** | |
334 | * devfreq_monitor_stop() - Stop load monitoring of a devfreq instance | |
335 | * @devfreq: the devfreq instance. | |
336 | * | |
337 | * Helper function to stop devfreq device load monitoing. Function | |
338 | * to be called from governor in response to DEVFREQ_GOV_STOP | |
339 | * event when device is removed from devfreq framework. | |
340 | */ | |
341 | void devfreq_monitor_stop(struct devfreq *devfreq) | |
342 | { | |
343 | cancel_delayed_work_sync(&devfreq->work); | |
344 | } | |
6dcdd8e3 | 345 | EXPORT_SYMBOL(devfreq_monitor_stop); |
7e6fdd4b RV |
346 | |
347 | /** | |
348 | * devfreq_monitor_suspend() - Suspend load monitoring of a devfreq instance | |
349 | * @devfreq: the devfreq instance. | |
350 | * | |
351 | * Helper function to suspend devfreq device load monitoing. Function | |
352 | * to be called from governor in response to DEVFREQ_GOV_SUSPEND | |
353 | * event or when polling interval is set to zero. | |
354 | * | |
355 | * Note: Though this function is same as devfreq_monitor_stop(), | |
356 | * intentionally kept separate to provide hooks for collecting | |
357 | * transition statistics. | |
358 | */ | |
359 | void devfreq_monitor_suspend(struct devfreq *devfreq) | |
360 | { | |
361 | mutex_lock(&devfreq->lock); | |
362 | if (devfreq->stop_polling) { | |
363 | mutex_unlock(&devfreq->lock); | |
364 | return; | |
365 | } | |
366 | ||
39688ce6 | 367 | devfreq_update_status(devfreq, devfreq->previous_freq); |
7e6fdd4b RV |
368 | devfreq->stop_polling = true; |
369 | mutex_unlock(&devfreq->lock); | |
370 | cancel_delayed_work_sync(&devfreq->work); | |
371 | } | |
6dcdd8e3 | 372 | EXPORT_SYMBOL(devfreq_monitor_suspend); |
7e6fdd4b RV |
373 | |
374 | /** | |
375 | * devfreq_monitor_resume() - Resume load monitoring of a devfreq instance | |
376 | * @devfreq: the devfreq instance. | |
377 | * | |
378 | * Helper function to resume devfreq device load monitoing. Function | |
379 | * to be called from governor in response to DEVFREQ_GOV_RESUME | |
380 | * event or when polling interval is set to non-zero. | |
381 | */ | |
382 | void devfreq_monitor_resume(struct devfreq *devfreq) | |
383 | { | |
39688ce6 RV |
384 | unsigned long freq; |
385 | ||
7e6fdd4b RV |
386 | mutex_lock(&devfreq->lock); |
387 | if (!devfreq->stop_polling) | |
388 | goto out; | |
389 | ||
390 | if (!delayed_work_pending(&devfreq->work) && | |
391 | devfreq->profile->polling_ms) | |
392 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
393 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
39688ce6 RV |
394 | |
395 | devfreq->last_stat_updated = jiffies; | |
7e6fdd4b RV |
396 | devfreq->stop_polling = false; |
397 | ||
39688ce6 RV |
398 | if (devfreq->profile->get_cur_freq && |
399 | !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) | |
400 | devfreq->previous_freq = freq; | |
401 | ||
7e6fdd4b RV |
402 | out: |
403 | mutex_unlock(&devfreq->lock); | |
404 | } | |
6dcdd8e3 | 405 | EXPORT_SYMBOL(devfreq_monitor_resume); |
7e6fdd4b RV |
406 | |
407 | /** | |
408 | * devfreq_interval_update() - Update device devfreq monitoring interval | |
409 | * @devfreq: the devfreq instance. | |
410 | * @delay: new polling interval to be set. | |
411 | * | |
412 | * Helper function to set new load monitoring polling interval. Function | |
413 | * to be called from governor in response to DEVFREQ_GOV_INTERVAL event. | |
414 | */ | |
415 | void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) | |
416 | { | |
417 | unsigned int cur_delay = devfreq->profile->polling_ms; | |
418 | unsigned int new_delay = *delay; | |
419 | ||
420 | mutex_lock(&devfreq->lock); | |
421 | devfreq->profile->polling_ms = new_delay; | |
422 | ||
423 | if (devfreq->stop_polling) | |
424 | goto out; | |
425 | ||
426 | /* if new delay is zero, stop polling */ | |
427 | if (!new_delay) { | |
428 | mutex_unlock(&devfreq->lock); | |
429 | cancel_delayed_work_sync(&devfreq->work); | |
430 | return; | |
431 | } | |
432 | ||
433 | /* if current delay is zero, start polling with new delay */ | |
434 | if (!cur_delay) { | |
435 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
436 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
437 | goto out; | |
438 | } | |
439 | ||
440 | /* if current delay is greater than new delay, restart polling */ | |
441 | if (cur_delay > new_delay) { | |
442 | mutex_unlock(&devfreq->lock); | |
443 | cancel_delayed_work_sync(&devfreq->work); | |
444 | mutex_lock(&devfreq->lock); | |
445 | if (!devfreq->stop_polling) | |
446 | queue_delayed_work(devfreq_wq, &devfreq->work, | |
447 | msecs_to_jiffies(devfreq->profile->polling_ms)); | |
448 | } | |
449 | out: | |
450 | mutex_unlock(&devfreq->lock); | |
451 | } | |
6dcdd8e3 | 452 | EXPORT_SYMBOL(devfreq_interval_update); |
a3c98b8b MH |
453 | |
454 | /** | |
455 | * devfreq_notifier_call() - Notify that the device frequency requirements | |
456 | * has been changed out of devfreq framework. | |
c5b4a1c1 NM |
457 | * @nb: the notifier_block (supposed to be devfreq->nb) |
458 | * @type: not used | |
459 | * @devp: not used | |
a3c98b8b MH |
460 | * |
461 | * Called by a notifier that uses devfreq->nb. | |
462 | */ | |
463 | static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, | |
464 | void *devp) | |
465 | { | |
466 | struct devfreq *devfreq = container_of(nb, struct devfreq, nb); | |
467 | int ret; | |
468 | ||
469 | mutex_lock(&devfreq->lock); | |
470 | ret = update_devfreq(devfreq); | |
471 | mutex_unlock(&devfreq->lock); | |
472 | ||
473 | return ret; | |
474 | } | |
475 | ||
476 | /** | |
7e6fdd4b | 477 | * _remove_devfreq() - Remove devfreq from the list and release its resources. |
a3c98b8b | 478 | * @devfreq: the devfreq struct |
a3c98b8b | 479 | */ |
585fc83e | 480 | static void _remove_devfreq(struct devfreq *devfreq) |
a3c98b8b | 481 | { |
7e6fdd4b RV |
482 | mutex_lock(&devfreq_list_lock); |
483 | if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { | |
484 | mutex_unlock(&devfreq_list_lock); | |
485 | dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n"); | |
a3c98b8b MH |
486 | return; |
487 | } | |
7e6fdd4b RV |
488 | list_del(&devfreq->node); |
489 | mutex_unlock(&devfreq_list_lock); | |
a3c98b8b | 490 | |
1b5c1be2 NM |
491 | if (devfreq->governor) |
492 | devfreq->governor->event_handler(devfreq, | |
493 | DEVFREQ_GOV_STOP, NULL); | |
a3c98b8b MH |
494 | |
495 | if (devfreq->profile->exit) | |
496 | devfreq->profile->exit(devfreq->dev.parent); | |
497 | ||
a3c98b8b | 498 | mutex_destroy(&devfreq->lock); |
a3c98b8b MH |
499 | kfree(devfreq); |
500 | } | |
501 | ||
502 | /** | |
503 | * devfreq_dev_release() - Callback for struct device to release the device. | |
504 | * @dev: the devfreq device | |
505 | * | |
506 | * This calls _remove_devfreq() if _remove_devfreq() is not called. | |
a3c98b8b MH |
507 | */ |
508 | static void devfreq_dev_release(struct device *dev) | |
509 | { | |
510 | struct devfreq *devfreq = to_devfreq(dev); | |
a3c98b8b | 511 | |
585fc83e | 512 | _remove_devfreq(devfreq); |
a3c98b8b MH |
513 | } |
514 | ||
515 | /** | |
516 | * devfreq_add_device() - Add devfreq feature to the device | |
517 | * @dev: the device to add devfreq feature. | |
518 | * @profile: device-specific profile to run devfreq. | |
1b5c1be2 | 519 | * @governor_name: name of the policy to choose frequency. |
a3c98b8b MH |
520 | * @data: private data for the governor. The devfreq framework does not |
521 | * touch this value. | |
522 | */ | |
523 | struct devfreq *devfreq_add_device(struct device *dev, | |
524 | struct devfreq_dev_profile *profile, | |
1b5c1be2 | 525 | const char *governor_name, |
a3c98b8b MH |
526 | void *data) |
527 | { | |
528 | struct devfreq *devfreq; | |
1b5c1be2 | 529 | struct devfreq_governor *governor; |
a3c98b8b MH |
530 | int err = 0; |
531 | ||
1b5c1be2 | 532 | if (!dev || !profile || !governor_name) { |
a3c98b8b MH |
533 | dev_err(dev, "%s: Invalid parameters.\n", __func__); |
534 | return ERR_PTR(-EINVAL); | |
535 | } | |
536 | ||
7e6fdd4b RV |
537 | mutex_lock(&devfreq_list_lock); |
538 | devfreq = find_device_devfreq(dev); | |
539 | mutex_unlock(&devfreq_list_lock); | |
540 | if (!IS_ERR(devfreq)) { | |
9d0109be CC |
541 | dev_err(dev, "%s: Unable to create devfreq for the device.\n", |
542 | __func__); | |
7e6fdd4b RV |
543 | err = -EINVAL; |
544 | goto err_out; | |
a3c98b8b MH |
545 | } |
546 | ||
547 | devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); | |
548 | if (!devfreq) { | |
a3c98b8b | 549 | err = -ENOMEM; |
3f19f08a | 550 | goto err_out; |
a3c98b8b MH |
551 | } |
552 | ||
553 | mutex_init(&devfreq->lock); | |
554 | mutex_lock(&devfreq->lock); | |
555 | devfreq->dev.parent = dev; | |
556 | devfreq->dev.class = devfreq_class; | |
557 | devfreq->dev.release = devfreq_dev_release; | |
558 | devfreq->profile = profile; | |
1b5c1be2 | 559 | strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); |
a3c98b8b | 560 | devfreq->previous_freq = profile->initial_freq; |
8d39fc08 | 561 | devfreq->last_status.current_frequency = profile->initial_freq; |
a3c98b8b | 562 | devfreq->data = data; |
a3c98b8b MH |
563 | devfreq->nb.notifier_call = devfreq_notifier_call; |
564 | ||
0ec09ac2 CC |
565 | if (!devfreq->profile->max_state && !devfreq->profile->freq_table) { |
566 | mutex_unlock(&devfreq->lock); | |
567 | devfreq_set_freq_table(devfreq); | |
568 | mutex_lock(&devfreq->lock); | |
569 | } | |
570 | ||
02aa2a37 | 571 | dev_set_name(&devfreq->dev, "%s", dev_name(dev)); |
a3c98b8b MH |
572 | err = device_register(&devfreq->dev); |
573 | if (err) { | |
7e6fdd4b | 574 | mutex_unlock(&devfreq->lock); |
6d3cbfa7 | 575 | goto err_out; |
a3c98b8b MH |
576 | } |
577 | ||
9d0109be CC |
578 | devfreq->trans_table = devm_kzalloc(&devfreq->dev, |
579 | sizeof(unsigned int) * | |
3e1d7fb0 MH |
580 | devfreq->profile->max_state * |
581 | devfreq->profile->max_state, | |
582 | GFP_KERNEL); | |
9d0109be CC |
583 | devfreq->time_in_state = devm_kzalloc(&devfreq->dev, |
584 | sizeof(unsigned long) * | |
3e1d7fb0 MH |
585 | devfreq->profile->max_state, |
586 | GFP_KERNEL); | |
587 | devfreq->last_stat_updated = jiffies; | |
588 | ||
0fe3a664 CC |
589 | srcu_init_notifier_head(&devfreq->transition_notifier_list); |
590 | ||
a3c98b8b MH |
591 | mutex_unlock(&devfreq->lock); |
592 | ||
a3c98b8b | 593 | mutex_lock(&devfreq_list_lock); |
a3c98b8b MH |
594 | list_add(&devfreq->node, &devfreq_list); |
595 | ||
1b5c1be2 | 596 | governor = find_devfreq_governor(devfreq->governor_name); |
73613b16 CC |
597 | if (IS_ERR(governor)) { |
598 | dev_err(dev, "%s: Unable to find governor for the device\n", | |
599 | __func__); | |
600 | err = PTR_ERR(governor); | |
601 | goto err_init; | |
602 | } | |
603 | ||
604 | devfreq->governor = governor; | |
605 | err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START, | |
606 | NULL); | |
7e6fdd4b RV |
607 | if (err) { |
608 | dev_err(dev, "%s: Unable to start governor for the device\n", | |
609 | __func__); | |
610 | goto err_init; | |
a3c98b8b | 611 | } |
0f376c9c | 612 | mutex_unlock(&devfreq_list_lock); |
7e6fdd4b | 613 | |
3f19f08a AL |
614 | return devfreq; |
615 | ||
a3c98b8b | 616 | err_init: |
7e6fdd4b | 617 | list_del(&devfreq->node); |
0f376c9c AL |
618 | mutex_unlock(&devfreq_list_lock); |
619 | ||
a3c98b8b | 620 | device_unregister(&devfreq->dev); |
3f19f08a AL |
621 | err_out: |
622 | return ERR_PTR(err); | |
a3c98b8b | 623 | } |
7e6fdd4b | 624 | EXPORT_SYMBOL(devfreq_add_device); |
a3c98b8b MH |
625 | |
626 | /** | |
627 | * devfreq_remove_device() - Remove devfreq feature from a device. | |
c5b4a1c1 | 628 | * @devfreq: the devfreq instance to be removed |
de9c7394 MH |
629 | * |
630 | * The opposite of devfreq_add_device(). | |
a3c98b8b MH |
631 | */ |
632 | int devfreq_remove_device(struct devfreq *devfreq) | |
633 | { | |
634 | if (!devfreq) | |
635 | return -EINVAL; | |
636 | ||
585fc83e | 637 | device_unregister(&devfreq->dev); |
9f3bdd4f | 638 | |
a3c98b8b MH |
639 | return 0; |
640 | } | |
7e6fdd4b | 641 | EXPORT_SYMBOL(devfreq_remove_device); |
a3c98b8b | 642 | |
8cd84092 CC |
643 | static int devm_devfreq_dev_match(struct device *dev, void *res, void *data) |
644 | { | |
645 | struct devfreq **r = res; | |
646 | ||
647 | if (WARN_ON(!r || !*r)) | |
648 | return 0; | |
649 | ||
650 | return *r == data; | |
651 | } | |
652 | ||
653 | static void devm_devfreq_dev_release(struct device *dev, void *res) | |
654 | { | |
655 | devfreq_remove_device(*(struct devfreq **)res); | |
656 | } | |
657 | ||
658 | /** | |
659 | * devm_devfreq_add_device() - Resource-managed devfreq_add_device() | |
660 | * @dev: the device to add devfreq feature. | |
661 | * @profile: device-specific profile to run devfreq. | |
662 | * @governor_name: name of the policy to choose frequency. | |
663 | * @data: private data for the governor. The devfreq framework does not | |
664 | * touch this value. | |
665 | * | |
666 | * This function manages automatically the memory of devfreq device using device | |
667 | * resource management and simplify the free operation for memory of devfreq | |
668 | * device. | |
669 | */ | |
670 | struct devfreq *devm_devfreq_add_device(struct device *dev, | |
671 | struct devfreq_dev_profile *profile, | |
672 | const char *governor_name, | |
673 | void *data) | |
674 | { | |
675 | struct devfreq **ptr, *devfreq; | |
676 | ||
677 | ptr = devres_alloc(devm_devfreq_dev_release, sizeof(*ptr), GFP_KERNEL); | |
678 | if (!ptr) | |
679 | return ERR_PTR(-ENOMEM); | |
680 | ||
681 | devfreq = devfreq_add_device(dev, profile, governor_name, data); | |
682 | if (IS_ERR(devfreq)) { | |
683 | devres_free(ptr); | |
684 | return ERR_PTR(-ENOMEM); | |
685 | } | |
686 | ||
687 | *ptr = devfreq; | |
688 | devres_add(dev, ptr); | |
689 | ||
690 | return devfreq; | |
691 | } | |
692 | EXPORT_SYMBOL(devm_devfreq_add_device); | |
693 | ||
8f510aeb CC |
694 | #ifdef CONFIG_OF |
695 | /* | |
696 | * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree | |
697 | * @dev - instance to the given device | |
698 | * @index - index into list of devfreq | |
699 | * | |
700 | * return the instance of devfreq device | |
701 | */ | |
702 | struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) | |
703 | { | |
704 | struct device_node *node; | |
705 | struct devfreq *devfreq; | |
706 | ||
707 | if (!dev) | |
708 | return ERR_PTR(-EINVAL); | |
709 | ||
710 | if (!dev->of_node) | |
711 | return ERR_PTR(-EINVAL); | |
712 | ||
713 | node = of_parse_phandle(dev->of_node, "devfreq", index); | |
714 | if (!node) | |
715 | return ERR_PTR(-ENODEV); | |
716 | ||
717 | mutex_lock(&devfreq_list_lock); | |
718 | list_for_each_entry(devfreq, &devfreq_list, node) { | |
719 | if (devfreq->dev.parent | |
720 | && devfreq->dev.parent->of_node == node) { | |
721 | mutex_unlock(&devfreq_list_lock); | |
3427c6f0 | 722 | of_node_put(node); |
8f510aeb CC |
723 | return devfreq; |
724 | } | |
725 | } | |
726 | mutex_unlock(&devfreq_list_lock); | |
3427c6f0 | 727 | of_node_put(node); |
8f510aeb CC |
728 | |
729 | return ERR_PTR(-EPROBE_DEFER); | |
730 | } | |
731 | #else | |
732 | struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) | |
733 | { | |
734 | return ERR_PTR(-ENODEV); | |
735 | } | |
736 | #endif /* CONFIG_OF */ | |
737 | EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle); | |
738 | ||
8cd84092 CC |
739 | /** |
740 | * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device() | |
741 | * @dev: the device to add devfreq feature. | |
742 | * @devfreq: the devfreq instance to be removed | |
743 | */ | |
744 | void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq) | |
745 | { | |
746 | WARN_ON(devres_release(dev, devm_devfreq_dev_release, | |
747 | devm_devfreq_dev_match, devfreq)); | |
748 | } | |
749 | EXPORT_SYMBOL(devm_devfreq_remove_device); | |
750 | ||
206c30cf RV |
751 | /** |
752 | * devfreq_suspend_device() - Suspend devfreq of a device. | |
753 | * @devfreq: the devfreq instance to be suspended | |
de9c7394 MH |
754 | * |
755 | * This function is intended to be called by the pm callbacks | |
756 | * (e.g., runtime_suspend, suspend) of the device driver that | |
757 | * holds the devfreq. | |
206c30cf RV |
758 | */ |
759 | int devfreq_suspend_device(struct devfreq *devfreq) | |
760 | { | |
a3c98b8b MH |
761 | if (!devfreq) |
762 | return -EINVAL; | |
763 | ||
1b5c1be2 NM |
764 | if (!devfreq->governor) |
765 | return 0; | |
766 | ||
206c30cf RV |
767 | return devfreq->governor->event_handler(devfreq, |
768 | DEVFREQ_GOV_SUSPEND, NULL); | |
769 | } | |
770 | EXPORT_SYMBOL(devfreq_suspend_device); | |
771 | ||
772 | /** | |
773 | * devfreq_resume_device() - Resume devfreq of a device. | |
774 | * @devfreq: the devfreq instance to be resumed | |
de9c7394 MH |
775 | * |
776 | * This function is intended to be called by the pm callbacks | |
777 | * (e.g., runtime_resume, resume) of the device driver that | |
778 | * holds the devfreq. | |
206c30cf RV |
779 | */ |
780 | int devfreq_resume_device(struct devfreq *devfreq) | |
781 | { | |
782 | if (!devfreq) | |
783 | return -EINVAL; | |
784 | ||
1b5c1be2 NM |
785 | if (!devfreq->governor) |
786 | return 0; | |
787 | ||
206c30cf RV |
788 | return devfreq->governor->event_handler(devfreq, |
789 | DEVFREQ_GOV_RESUME, NULL); | |
790 | } | |
791 | EXPORT_SYMBOL(devfreq_resume_device); | |
792 | ||
3aa173b8 NM |
793 | /** |
794 | * devfreq_add_governor() - Add devfreq governor | |
795 | * @governor: the devfreq governor to be added | |
796 | */ | |
797 | int devfreq_add_governor(struct devfreq_governor *governor) | |
798 | { | |
799 | struct devfreq_governor *g; | |
1b5c1be2 | 800 | struct devfreq *devfreq; |
3aa173b8 NM |
801 | int err = 0; |
802 | ||
803 | if (!governor) { | |
804 | pr_err("%s: Invalid parameters.\n", __func__); | |
805 | return -EINVAL; | |
806 | } | |
807 | ||
808 | mutex_lock(&devfreq_list_lock); | |
809 | g = find_devfreq_governor(governor->name); | |
810 | if (!IS_ERR(g)) { | |
811 | pr_err("%s: governor %s already registered\n", __func__, | |
812 | g->name); | |
813 | err = -EINVAL; | |
814 | goto err_out; | |
815 | } | |
9f3bdd4f | 816 | |
3aa173b8 NM |
817 | list_add(&governor->node, &devfreq_governor_list); |
818 | ||
1b5c1be2 NM |
819 | list_for_each_entry(devfreq, &devfreq_list, node) { |
820 | int ret = 0; | |
821 | struct device *dev = devfreq->dev.parent; | |
822 | ||
823 | if (!strncmp(devfreq->governor_name, governor->name, | |
824 | DEVFREQ_NAME_LEN)) { | |
825 | /* The following should never occur */ | |
826 | if (devfreq->governor) { | |
827 | dev_warn(dev, | |
828 | "%s: Governor %s already present\n", | |
829 | __func__, devfreq->governor->name); | |
830 | ret = devfreq->governor->event_handler(devfreq, | |
831 | DEVFREQ_GOV_STOP, NULL); | |
832 | if (ret) { | |
833 | dev_warn(dev, | |
834 | "%s: Governor %s stop = %d\n", | |
835 | __func__, | |
836 | devfreq->governor->name, ret); | |
837 | } | |
838 | /* Fall through */ | |
839 | } | |
840 | devfreq->governor = governor; | |
841 | ret = devfreq->governor->event_handler(devfreq, | |
842 | DEVFREQ_GOV_START, NULL); | |
843 | if (ret) { | |
844 | dev_warn(dev, "%s: Governor %s start=%d\n", | |
845 | __func__, devfreq->governor->name, | |
846 | ret); | |
847 | } | |
a3c98b8b MH |
848 | } |
849 | } | |
850 | ||
3aa173b8 NM |
851 | err_out: |
852 | mutex_unlock(&devfreq_list_lock); | |
a3c98b8b | 853 | |
3aa173b8 NM |
854 | return err; |
855 | } | |
856 | EXPORT_SYMBOL(devfreq_add_governor); | |
a3c98b8b | 857 | |
3aa173b8 | 858 | /** |
bafeb42b | 859 | * devfreq_remove_governor() - Remove devfreq feature from a device. |
3aa173b8 NM |
860 | * @governor: the devfreq governor to be removed |
861 | */ | |
862 | int devfreq_remove_governor(struct devfreq_governor *governor) | |
863 | { | |
864 | struct devfreq_governor *g; | |
1b5c1be2 | 865 | struct devfreq *devfreq; |
3aa173b8 NM |
866 | int err = 0; |
867 | ||
868 | if (!governor) { | |
869 | pr_err("%s: Invalid parameters.\n", __func__); | |
870 | return -EINVAL; | |
871 | } | |
872 | ||
873 | mutex_lock(&devfreq_list_lock); | |
874 | g = find_devfreq_governor(governor->name); | |
875 | if (IS_ERR(g)) { | |
876 | pr_err("%s: governor %s not registered\n", __func__, | |
b9e1c8e8 | 877 | governor->name); |
f9c08e2a | 878 | err = PTR_ERR(g); |
3aa173b8 NM |
879 | goto err_out; |
880 | } | |
1b5c1be2 NM |
881 | list_for_each_entry(devfreq, &devfreq_list, node) { |
882 | int ret; | |
883 | struct device *dev = devfreq->dev.parent; | |
884 | ||
885 | if (!strncmp(devfreq->governor_name, governor->name, | |
886 | DEVFREQ_NAME_LEN)) { | |
887 | /* we should have a devfreq governor! */ | |
888 | if (!devfreq->governor) { | |
889 | dev_warn(dev, "%s: Governor %s NOT present\n", | |
890 | __func__, governor->name); | |
891 | continue; | |
892 | /* Fall through */ | |
893 | } | |
894 | ret = devfreq->governor->event_handler(devfreq, | |
895 | DEVFREQ_GOV_STOP, NULL); | |
896 | if (ret) { | |
897 | dev_warn(dev, "%s: Governor %s stop=%d\n", | |
898 | __func__, devfreq->governor->name, | |
899 | ret); | |
900 | } | |
901 | devfreq->governor = NULL; | |
902 | } | |
903 | } | |
3aa173b8 NM |
904 | |
905 | list_del(&governor->node); | |
906 | err_out: | |
907 | mutex_unlock(&devfreq_list_lock); | |
908 | ||
909 | return err; | |
a3c98b8b | 910 | } |
3aa173b8 | 911 | EXPORT_SYMBOL(devfreq_remove_governor); |
a3c98b8b | 912 | |
a93d6b0a | 913 | static ssize_t governor_show(struct device *dev, |
9005b650 MH |
914 | struct device_attribute *attr, char *buf) |
915 | { | |
1b5c1be2 NM |
916 | if (!to_devfreq(dev)->governor) |
917 | return -EINVAL; | |
918 | ||
9005b650 MH |
919 | return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name); |
920 | } | |
921 | ||
a93d6b0a | 922 | static ssize_t governor_store(struct device *dev, struct device_attribute *attr, |
0359d1af NM |
923 | const char *buf, size_t count) |
924 | { | |
925 | struct devfreq *df = to_devfreq(dev); | |
926 | int ret; | |
927 | char str_governor[DEVFREQ_NAME_LEN + 1]; | |
928 | struct devfreq_governor *governor; | |
929 | ||
930 | ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor); | |
931 | if (ret != 1) | |
932 | return -EINVAL; | |
933 | ||
934 | mutex_lock(&devfreq_list_lock); | |
935 | governor = find_devfreq_governor(str_governor); | |
936 | if (IS_ERR(governor)) { | |
937 | ret = PTR_ERR(governor); | |
938 | goto out; | |
939 | } | |
14a21e7b TJ |
940 | if (df->governor == governor) { |
941 | ret = 0; | |
0359d1af | 942 | goto out; |
14a21e7b | 943 | } |
0359d1af NM |
944 | |
945 | if (df->governor) { | |
946 | ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL); | |
947 | if (ret) { | |
948 | dev_warn(dev, "%s: Governor %s not stopped(%d)\n", | |
949 | __func__, df->governor->name, ret); | |
950 | goto out; | |
951 | } | |
952 | } | |
953 | df->governor = governor; | |
954 | strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN); | |
955 | ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL); | |
956 | if (ret) | |
957 | dev_warn(dev, "%s: Governor %s not started(%d)\n", | |
958 | __func__, df->governor->name, ret); | |
959 | out: | |
960 | mutex_unlock(&devfreq_list_lock); | |
961 | ||
962 | if (!ret) | |
963 | ret = count; | |
964 | return ret; | |
965 | } | |
a93d6b0a GKH |
966 | static DEVICE_ATTR_RW(governor); |
967 | ||
968 | static ssize_t available_governors_show(struct device *d, | |
969 | struct device_attribute *attr, | |
970 | char *buf) | |
50a5b33e NM |
971 | { |
972 | struct devfreq_governor *tmp_governor; | |
973 | ssize_t count = 0; | |
974 | ||
975 | mutex_lock(&devfreq_list_lock); | |
976 | list_for_each_entry(tmp_governor, &devfreq_governor_list, node) | |
977 | count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), | |
978 | "%s ", tmp_governor->name); | |
979 | mutex_unlock(&devfreq_list_lock); | |
980 | ||
981 | /* Truncate the trailing space */ | |
982 | if (count) | |
983 | count--; | |
984 | ||
985 | count += sprintf(&buf[count], "\n"); | |
986 | ||
987 | return count; | |
988 | } | |
a93d6b0a | 989 | static DEVICE_ATTR_RO(available_governors); |
0359d1af | 990 | |
a93d6b0a GKH |
991 | static ssize_t cur_freq_show(struct device *dev, struct device_attribute *attr, |
992 | char *buf) | |
7f98a905 RV |
993 | { |
994 | unsigned long freq; | |
995 | struct devfreq *devfreq = to_devfreq(dev); | |
996 | ||
997 | if (devfreq->profile->get_cur_freq && | |
998 | !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) | |
9d0109be | 999 | return sprintf(buf, "%lu\n", freq); |
7f98a905 RV |
1000 | |
1001 | return sprintf(buf, "%lu\n", devfreq->previous_freq); | |
1002 | } | |
a93d6b0a | 1003 | static DEVICE_ATTR_RO(cur_freq); |
7f98a905 | 1004 | |
a93d6b0a GKH |
1005 | static ssize_t target_freq_show(struct device *dev, |
1006 | struct device_attribute *attr, char *buf) | |
9005b650 MH |
1007 | { |
1008 | return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq); | |
1009 | } | |
a93d6b0a | 1010 | static DEVICE_ATTR_RO(target_freq); |
9005b650 | 1011 | |
a93d6b0a | 1012 | static ssize_t polling_interval_show(struct device *dev, |
9005b650 MH |
1013 | struct device_attribute *attr, char *buf) |
1014 | { | |
1015 | return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms); | |
1016 | } | |
1017 | ||
a93d6b0a | 1018 | static ssize_t polling_interval_store(struct device *dev, |
9005b650 MH |
1019 | struct device_attribute *attr, |
1020 | const char *buf, size_t count) | |
1021 | { | |
1022 | struct devfreq *df = to_devfreq(dev); | |
1023 | unsigned int value; | |
1024 | int ret; | |
1025 | ||
1b5c1be2 NM |
1026 | if (!df->governor) |
1027 | return -EINVAL; | |
1028 | ||
9005b650 MH |
1029 | ret = sscanf(buf, "%u", &value); |
1030 | if (ret != 1) | |
12e26265 | 1031 | return -EINVAL; |
9005b650 | 1032 | |
7e6fdd4b | 1033 | df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL, &value); |
9005b650 MH |
1034 | ret = count; |
1035 | ||
9005b650 MH |
1036 | return ret; |
1037 | } | |
a93d6b0a | 1038 | static DEVICE_ATTR_RW(polling_interval); |
9005b650 | 1039 | |
a93d6b0a | 1040 | static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, |
6530b9de MH |
1041 | const char *buf, size_t count) |
1042 | { | |
1043 | struct devfreq *df = to_devfreq(dev); | |
1044 | unsigned long value; | |
1045 | int ret; | |
1046 | unsigned long max; | |
1047 | ||
1048 | ret = sscanf(buf, "%lu", &value); | |
1049 | if (ret != 1) | |
12e26265 | 1050 | return -EINVAL; |
6530b9de MH |
1051 | |
1052 | mutex_lock(&df->lock); | |
1053 | max = df->max_freq; | |
1054 | if (value && max && value > max) { | |
1055 | ret = -EINVAL; | |
1056 | goto unlock; | |
1057 | } | |
1058 | ||
1059 | df->min_freq = value; | |
1060 | update_devfreq(df); | |
1061 | ret = count; | |
1062 | unlock: | |
1063 | mutex_unlock(&df->lock); | |
6530b9de MH |
1064 | return ret; |
1065 | } | |
1066 | ||
a93d6b0a | 1067 | static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, |
6530b9de MH |
1068 | const char *buf, size_t count) |
1069 | { | |
1070 | struct devfreq *df = to_devfreq(dev); | |
1071 | unsigned long value; | |
1072 | int ret; | |
1073 | unsigned long min; | |
1074 | ||
1075 | ret = sscanf(buf, "%lu", &value); | |
1076 | if (ret != 1) | |
12e26265 | 1077 | return -EINVAL; |
6530b9de MH |
1078 | |
1079 | mutex_lock(&df->lock); | |
1080 | min = df->min_freq; | |
1081 | if (value && min && value < min) { | |
1082 | ret = -EINVAL; | |
1083 | goto unlock; | |
1084 | } | |
1085 | ||
1086 | df->max_freq = value; | |
1087 | update_devfreq(df); | |
1088 | ret = count; | |
1089 | unlock: | |
1090 | mutex_unlock(&df->lock); | |
6530b9de MH |
1091 | return ret; |
1092 | } | |
1093 | ||
3104fa30 CC |
1094 | #define show_one(name) \ |
1095 | static ssize_t name##_show \ | |
1096 | (struct device *dev, struct device_attribute *attr, char *buf) \ | |
1097 | { \ | |
1098 | return sprintf(buf, "%lu\n", to_devfreq(dev)->name); \ | |
6530b9de | 1099 | } |
3104fa30 CC |
1100 | show_one(min_freq); |
1101 | show_one(max_freq); | |
1102 | ||
1103 | static DEVICE_ATTR_RW(min_freq); | |
a93d6b0a | 1104 | static DEVICE_ATTR_RW(max_freq); |
6530b9de | 1105 | |
a93d6b0a GKH |
1106 | static ssize_t available_frequencies_show(struct device *d, |
1107 | struct device_attribute *attr, | |
1108 | char *buf) | |
d287de85 NM |
1109 | { |
1110 | struct devfreq *df = to_devfreq(d); | |
1111 | struct device *dev = df->dev.parent; | |
47d43ba7 | 1112 | struct dev_pm_opp *opp; |
d287de85 NM |
1113 | ssize_t count = 0; |
1114 | unsigned long freq = 0; | |
1115 | ||
1116 | rcu_read_lock(); | |
1117 | do { | |
5d4879cd | 1118 | opp = dev_pm_opp_find_freq_ceil(dev, &freq); |
d287de85 NM |
1119 | if (IS_ERR(opp)) |
1120 | break; | |
1121 | ||
1122 | count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), | |
1123 | "%lu ", freq); | |
1124 | freq++; | |
1125 | } while (1); | |
1126 | rcu_read_unlock(); | |
1127 | ||
1128 | /* Truncate the trailing space */ | |
1129 | if (count) | |
1130 | count--; | |
1131 | ||
1132 | count += sprintf(&buf[count], "\n"); | |
1133 | ||
1134 | return count; | |
1135 | } | |
a93d6b0a | 1136 | static DEVICE_ATTR_RO(available_frequencies); |
d287de85 | 1137 | |
a93d6b0a GKH |
1138 | static ssize_t trans_stat_show(struct device *dev, |
1139 | struct device_attribute *attr, char *buf) | |
e552bbaf JL |
1140 | { |
1141 | struct devfreq *devfreq = to_devfreq(dev); | |
1142 | ssize_t len; | |
39688ce6 | 1143 | int i, j; |
e552bbaf JL |
1144 | unsigned int max_state = devfreq->profile->max_state; |
1145 | ||
39688ce6 RV |
1146 | if (!devfreq->stop_polling && |
1147 | devfreq_update_status(devfreq, devfreq->previous_freq)) | |
e552bbaf | 1148 | return 0; |
34bd3220 MH |
1149 | if (max_state == 0) |
1150 | return sprintf(buf, "Not Supported.\n"); | |
e552bbaf | 1151 | |
d7df1e46 CC |
1152 | len = sprintf(buf, " From : To\n"); |
1153 | len += sprintf(buf + len, " :"); | |
e552bbaf | 1154 | for (i = 0; i < max_state; i++) |
d7df1e46 | 1155 | len += sprintf(buf + len, "%10lu", |
e552bbaf JL |
1156 | devfreq->profile->freq_table[i]); |
1157 | ||
1158 | len += sprintf(buf + len, " time(ms)\n"); | |
1159 | ||
1160 | for (i = 0; i < max_state; i++) { | |
1161 | if (devfreq->profile->freq_table[i] | |
1162 | == devfreq->previous_freq) { | |
1163 | len += sprintf(buf + len, "*"); | |
1164 | } else { | |
1165 | len += sprintf(buf + len, " "); | |
1166 | } | |
d7df1e46 | 1167 | len += sprintf(buf + len, "%10lu:", |
e552bbaf JL |
1168 | devfreq->profile->freq_table[i]); |
1169 | for (j = 0; j < max_state; j++) | |
d7df1e46 | 1170 | len += sprintf(buf + len, "%10u", |
e552bbaf JL |
1171 | devfreq->trans_table[(i * max_state) + j]); |
1172 | len += sprintf(buf + len, "%10u\n", | |
1173 | jiffies_to_msecs(devfreq->time_in_state[i])); | |
1174 | } | |
1175 | ||
1176 | len += sprintf(buf + len, "Total transition : %u\n", | |
1177 | devfreq->total_trans); | |
1178 | return len; | |
1179 | } | |
a93d6b0a GKH |
1180 | static DEVICE_ATTR_RO(trans_stat); |
1181 | ||
1182 | static struct attribute *devfreq_attrs[] = { | |
1183 | &dev_attr_governor.attr, | |
1184 | &dev_attr_available_governors.attr, | |
1185 | &dev_attr_cur_freq.attr, | |
1186 | &dev_attr_available_frequencies.attr, | |
1187 | &dev_attr_target_freq.attr, | |
1188 | &dev_attr_polling_interval.attr, | |
1189 | &dev_attr_min_freq.attr, | |
1190 | &dev_attr_max_freq.attr, | |
1191 | &dev_attr_trans_stat.attr, | |
1192 | NULL, | |
9005b650 | 1193 | }; |
a93d6b0a | 1194 | ATTRIBUTE_GROUPS(devfreq); |
9005b650 | 1195 | |
a3c98b8b MH |
1196 | static int __init devfreq_init(void) |
1197 | { | |
1198 | devfreq_class = class_create(THIS_MODULE, "devfreq"); | |
1199 | if (IS_ERR(devfreq_class)) { | |
1200 | pr_err("%s: couldn't create class\n", __FILE__); | |
1201 | return PTR_ERR(devfreq_class); | |
1202 | } | |
7e6fdd4b RV |
1203 | |
1204 | devfreq_wq = create_freezable_workqueue("devfreq_wq"); | |
ea7f4548 | 1205 | if (!devfreq_wq) { |
7e6fdd4b RV |
1206 | class_destroy(devfreq_class); |
1207 | pr_err("%s: couldn't create workqueue\n", __FILE__); | |
ea7f4548 | 1208 | return -ENOMEM; |
7e6fdd4b | 1209 | } |
a93d6b0a | 1210 | devfreq_class->dev_groups = devfreq_groups; |
7e6fdd4b | 1211 | |
a3c98b8b MH |
1212 | return 0; |
1213 | } | |
1214 | subsys_initcall(devfreq_init); | |
1215 | ||
a3c98b8b MH |
1216 | /* |
1217 | * The followings are helper functions for devfreq user device drivers with | |
1218 | * OPP framework. | |
1219 | */ | |
1220 | ||
1221 | /** | |
1222 | * devfreq_recommended_opp() - Helper function to get proper OPP for the | |
1223 | * freq value given to target callback. | |
c5b4a1c1 NM |
1224 | * @dev: The devfreq user device. (parent of devfreq) |
1225 | * @freq: The frequency given to target function | |
1226 | * @flags: Flags handed from devfreq framework. | |
a3c98b8b | 1227 | * |
bcb27549 NM |
1228 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
1229 | * protected pointer. The reason for the same is that the opp pointer which is | |
1230 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
1231 | * under the locked area. The pointer returned must be used prior to unlocking | |
1232 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
a3c98b8b | 1233 | */ |
47d43ba7 NM |
1234 | struct dev_pm_opp *devfreq_recommended_opp(struct device *dev, |
1235 | unsigned long *freq, | |
1236 | u32 flags) | |
a3c98b8b | 1237 | { |
47d43ba7 | 1238 | struct dev_pm_opp *opp; |
a3c98b8b | 1239 | |
ab5f299f MH |
1240 | if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) { |
1241 | /* The freq is an upper bound. opp should be lower */ | |
5d4879cd | 1242 | opp = dev_pm_opp_find_freq_floor(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_ceil(dev, freq); |
ab5f299f MH |
1247 | } else { |
1248 | /* The freq is an lower bound. opp should be higher */ | |
5d4879cd | 1249 | opp = dev_pm_opp_find_freq_ceil(dev, freq); |
ab5f299f MH |
1250 | |
1251 | /* If not available, use the closest opp */ | |
0779726c | 1252 | if (opp == ERR_PTR(-ERANGE)) |
5d4879cd | 1253 | opp = dev_pm_opp_find_freq_floor(dev, freq); |
ab5f299f MH |
1254 | } |
1255 | ||
a3c98b8b MH |
1256 | return opp; |
1257 | } | |
bd7e9277 | 1258 | EXPORT_SYMBOL(devfreq_recommended_opp); |
a3c98b8b MH |
1259 | |
1260 | /** | |
1261 | * devfreq_register_opp_notifier() - Helper function to get devfreq notified | |
1262 | * for any changes in the OPP availability | |
1263 | * changes | |
c5b4a1c1 NM |
1264 | * @dev: The devfreq user device. (parent of devfreq) |
1265 | * @devfreq: The devfreq object. | |
a3c98b8b MH |
1266 | */ |
1267 | int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) | |
1268 | { | |
389baed0 MH |
1269 | struct srcu_notifier_head *nh; |
1270 | int ret = 0; | |
a3c98b8b | 1271 | |
389baed0 | 1272 | rcu_read_lock(); |
5d4879cd | 1273 | nh = dev_pm_opp_get_notifier(dev); |
a3c98b8b | 1274 | if (IS_ERR(nh)) |
389baed0 MH |
1275 | ret = PTR_ERR(nh); |
1276 | rcu_read_unlock(); | |
1277 | if (!ret) | |
1278 | ret = srcu_notifier_chain_register(nh, &devfreq->nb); | |
1279 | ||
1280 | return ret; | |
a3c98b8b | 1281 | } |
bd7e9277 | 1282 | EXPORT_SYMBOL(devfreq_register_opp_notifier); |
a3c98b8b MH |
1283 | |
1284 | /** | |
1285 | * devfreq_unregister_opp_notifier() - Helper function to stop getting devfreq | |
1286 | * notified for any changes in the OPP | |
1287 | * availability changes anymore. | |
c5b4a1c1 NM |
1288 | * @dev: The devfreq user device. (parent of devfreq) |
1289 | * @devfreq: The devfreq object. | |
a3c98b8b MH |
1290 | * |
1291 | * At exit() callback of devfreq_dev_profile, this must be included if | |
1292 | * devfreq_recommended_opp is used. | |
1293 | */ | |
1294 | int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) | |
1295 | { | |
389baed0 MH |
1296 | struct srcu_notifier_head *nh; |
1297 | int ret = 0; | |
a3c98b8b | 1298 | |
389baed0 | 1299 | rcu_read_lock(); |
5d4879cd | 1300 | nh = dev_pm_opp_get_notifier(dev); |
a3c98b8b | 1301 | if (IS_ERR(nh)) |
389baed0 MH |
1302 | ret = PTR_ERR(nh); |
1303 | rcu_read_unlock(); | |
1304 | if (!ret) | |
1305 | ret = srcu_notifier_chain_unregister(nh, &devfreq->nb); | |
1306 | ||
1307 | return ret; | |
a3c98b8b | 1308 | } |
bd7e9277 | 1309 | EXPORT_SYMBOL(devfreq_unregister_opp_notifier); |
a3c98b8b | 1310 | |
d5b040d0 CC |
1311 | static void devm_devfreq_opp_release(struct device *dev, void *res) |
1312 | { | |
1313 | devfreq_unregister_opp_notifier(dev, *(struct devfreq **)res); | |
1314 | } | |
1315 | ||
1316 | /** | |
1317 | * devm_ devfreq_register_opp_notifier() | |
1318 | * - Resource-managed devfreq_register_opp_notifier() | |
1319 | * @dev: The devfreq user device. (parent of devfreq) | |
1320 | * @devfreq: The devfreq object. | |
1321 | */ | |
1322 | int devm_devfreq_register_opp_notifier(struct device *dev, | |
1323 | struct devfreq *devfreq) | |
1324 | { | |
1325 | struct devfreq **ptr; | |
1326 | int ret; | |
1327 | ||
1328 | ptr = devres_alloc(devm_devfreq_opp_release, sizeof(*ptr), GFP_KERNEL); | |
1329 | if (!ptr) | |
1330 | return -ENOMEM; | |
1331 | ||
1332 | ret = devfreq_register_opp_notifier(dev, devfreq); | |
1333 | if (ret) { | |
1334 | devres_free(ptr); | |
1335 | return ret; | |
1336 | } | |
1337 | ||
1338 | *ptr = devfreq; | |
1339 | devres_add(dev, ptr); | |
1340 | ||
1341 | return 0; | |
1342 | } | |
1343 | EXPORT_SYMBOL(devm_devfreq_register_opp_notifier); | |
1344 | ||
1345 | /** | |
1346 | * devm_devfreq_unregister_opp_notifier() | |
1347 | * - Resource-managed devfreq_unregister_opp_notifier() | |
1348 | * @dev: The devfreq user device. (parent of devfreq) | |
1349 | * @devfreq: The devfreq object. | |
1350 | */ | |
1351 | void devm_devfreq_unregister_opp_notifier(struct device *dev, | |
1352 | struct devfreq *devfreq) | |
1353 | { | |
1354 | WARN_ON(devres_release(dev, devm_devfreq_opp_release, | |
1355 | devm_devfreq_dev_match, devfreq)); | |
1356 | } | |
1357 | EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier); | |
1358 | ||
0fe3a664 CC |
1359 | /** |
1360 | * devfreq_register_notifier() - Register a driver with devfreq | |
1361 | * @devfreq: The devfreq object. | |
1362 | * @nb: The notifier block to register. | |
1363 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1364 | */ | |
1365 | int devfreq_register_notifier(struct devfreq *devfreq, | |
1366 | struct notifier_block *nb, | |
1367 | unsigned int list) | |
1368 | { | |
1369 | int ret = 0; | |
1370 | ||
1371 | if (!devfreq) | |
1372 | return -EINVAL; | |
1373 | ||
1374 | switch (list) { | |
1375 | case DEVFREQ_TRANSITION_NOTIFIER: | |
1376 | ret = srcu_notifier_chain_register( | |
1377 | &devfreq->transition_notifier_list, nb); | |
1378 | break; | |
1379 | default: | |
1380 | ret = -EINVAL; | |
1381 | } | |
1382 | ||
1383 | return ret; | |
1384 | } | |
1385 | EXPORT_SYMBOL(devfreq_register_notifier); | |
1386 | ||
1387 | /* | |
1388 | * devfreq_unregister_notifier() - Unregister a driver with devfreq | |
1389 | * @devfreq: The devfreq object. | |
1390 | * @nb: The notifier block to be unregistered. | |
1391 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1392 | */ | |
1393 | int devfreq_unregister_notifier(struct devfreq *devfreq, | |
1394 | struct notifier_block *nb, | |
1395 | unsigned int list) | |
1396 | { | |
1397 | int ret = 0; | |
1398 | ||
1399 | if (!devfreq) | |
1400 | return -EINVAL; | |
1401 | ||
1402 | switch (list) { | |
1403 | case DEVFREQ_TRANSITION_NOTIFIER: | |
1404 | ret = srcu_notifier_chain_unregister( | |
1405 | &devfreq->transition_notifier_list, nb); | |
1406 | break; | |
1407 | default: | |
1408 | ret = -EINVAL; | |
1409 | } | |
1410 | ||
1411 | return ret; | |
1412 | } | |
1413 | EXPORT_SYMBOL(devfreq_unregister_notifier); | |
1414 | ||
1415 | struct devfreq_notifier_devres { | |
1416 | struct devfreq *devfreq; | |
1417 | struct notifier_block *nb; | |
1418 | unsigned int list; | |
1419 | }; | |
1420 | ||
1421 | static void devm_devfreq_notifier_release(struct device *dev, void *res) | |
1422 | { | |
1423 | struct devfreq_notifier_devres *this = res; | |
1424 | ||
1425 | devfreq_unregister_notifier(this->devfreq, this->nb, this->list); | |
1426 | } | |
1427 | ||
1428 | /** | |
1429 | * devm_devfreq_register_notifier() | |
1430 | - Resource-managed devfreq_register_notifier() | |
1431 | * @dev: The devfreq user device. (parent of devfreq) | |
1432 | * @devfreq: The devfreq object. | |
1433 | * @nb: The notifier block to be unregistered. | |
1434 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1435 | */ | |
1436 | int devm_devfreq_register_notifier(struct device *dev, | |
1437 | struct devfreq *devfreq, | |
1438 | struct notifier_block *nb, | |
1439 | unsigned int list) | |
1440 | { | |
1441 | struct devfreq_notifier_devres *ptr; | |
1442 | int ret; | |
1443 | ||
1444 | ptr = devres_alloc(devm_devfreq_notifier_release, sizeof(*ptr), | |
1445 | GFP_KERNEL); | |
1446 | if (!ptr) | |
1447 | return -ENOMEM; | |
1448 | ||
1449 | ret = devfreq_register_notifier(devfreq, nb, list); | |
1450 | if (ret) { | |
1451 | devres_free(ptr); | |
1452 | return ret; | |
1453 | } | |
1454 | ||
1455 | ptr->devfreq = devfreq; | |
1456 | ptr->nb = nb; | |
1457 | ptr->list = list; | |
1458 | devres_add(dev, ptr); | |
1459 | ||
1460 | return 0; | |
1461 | } | |
1462 | EXPORT_SYMBOL(devm_devfreq_register_notifier); | |
1463 | ||
1464 | /** | |
1465 | * devm_devfreq_unregister_notifier() | |
1466 | - Resource-managed devfreq_unregister_notifier() | |
1467 | * @dev: The devfreq user device. (parent of devfreq) | |
1468 | * @devfreq: The devfreq object. | |
1469 | * @nb: The notifier block to be unregistered. | |
1470 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1471 | */ | |
1472 | void devm_devfreq_unregister_notifier(struct device *dev, | |
1473 | struct devfreq *devfreq, | |
1474 | struct notifier_block *nb, | |
1475 | unsigned int list) | |
1476 | { | |
1477 | WARN_ON(devres_release(dev, devm_devfreq_notifier_release, | |
1478 | devm_devfreq_dev_match, devfreq)); | |
1479 | } | |
1480 | EXPORT_SYMBOL(devm_devfreq_unregister_notifier); |