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)) { | |
541 | dev_err(dev, "%s: Unable to create devfreq for the device. It already has one.\n", __func__); | |
542 | err = -EINVAL; | |
543 | goto err_out; | |
a3c98b8b MH |
544 | } |
545 | ||
546 | devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); | |
547 | if (!devfreq) { | |
548 | dev_err(dev, "%s: Unable to create devfreq for the device\n", | |
549 | __func__); | |
550 | err = -ENOMEM; | |
3f19f08a | 551 | goto err_out; |
a3c98b8b MH |
552 | } |
553 | ||
554 | mutex_init(&devfreq->lock); | |
555 | mutex_lock(&devfreq->lock); | |
556 | devfreq->dev.parent = dev; | |
557 | devfreq->dev.class = devfreq_class; | |
558 | devfreq->dev.release = devfreq_dev_release; | |
559 | devfreq->profile = profile; | |
1b5c1be2 | 560 | strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); |
a3c98b8b | 561 | devfreq->previous_freq = profile->initial_freq; |
8d39fc08 | 562 | devfreq->last_status.current_frequency = profile->initial_freq; |
a3c98b8b | 563 | devfreq->data = data; |
a3c98b8b MH |
564 | devfreq->nb.notifier_call = devfreq_notifier_call; |
565 | ||
0ec09ac2 CC |
566 | if (!devfreq->profile->max_state && !devfreq->profile->freq_table) { |
567 | mutex_unlock(&devfreq->lock); | |
568 | devfreq_set_freq_table(devfreq); | |
569 | mutex_lock(&devfreq->lock); | |
570 | } | |
571 | ||
02aa2a37 | 572 | dev_set_name(&devfreq->dev, "%s", dev_name(dev)); |
a3c98b8b MH |
573 | err = device_register(&devfreq->dev); |
574 | if (err) { | |
7e6fdd4b | 575 | mutex_unlock(&devfreq->lock); |
6d3cbfa7 | 576 | goto err_out; |
a3c98b8b MH |
577 | } |
578 | ||
3e1d7fb0 MH |
579 | devfreq->trans_table = devm_kzalloc(&devfreq->dev, sizeof(unsigned int) * |
580 | devfreq->profile->max_state * | |
581 | devfreq->profile->max_state, | |
582 | GFP_KERNEL); | |
583 | devfreq->time_in_state = devm_kzalloc(&devfreq->dev, sizeof(unsigned long) * | |
584 | devfreq->profile->max_state, | |
585 | GFP_KERNEL); | |
586 | devfreq->last_stat_updated = jiffies; | |
587 | ||
0fe3a664 CC |
588 | srcu_init_notifier_head(&devfreq->transition_notifier_list); |
589 | ||
a3c98b8b MH |
590 | mutex_unlock(&devfreq->lock); |
591 | ||
a3c98b8b | 592 | mutex_lock(&devfreq_list_lock); |
a3c98b8b MH |
593 | list_add(&devfreq->node, &devfreq_list); |
594 | ||
1b5c1be2 | 595 | governor = find_devfreq_governor(devfreq->governor_name); |
73613b16 CC |
596 | if (IS_ERR(governor)) { |
597 | dev_err(dev, "%s: Unable to find governor for the device\n", | |
598 | __func__); | |
599 | err = PTR_ERR(governor); | |
600 | goto err_init; | |
601 | } | |
602 | ||
603 | devfreq->governor = governor; | |
604 | err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START, | |
605 | NULL); | |
7e6fdd4b RV |
606 | if (err) { |
607 | dev_err(dev, "%s: Unable to start governor for the device\n", | |
608 | __func__); | |
609 | goto err_init; | |
a3c98b8b | 610 | } |
0f376c9c | 611 | mutex_unlock(&devfreq_list_lock); |
7e6fdd4b | 612 | |
3f19f08a AL |
613 | return devfreq; |
614 | ||
a3c98b8b | 615 | err_init: |
7e6fdd4b | 616 | list_del(&devfreq->node); |
0f376c9c AL |
617 | mutex_unlock(&devfreq_list_lock); |
618 | ||
a3c98b8b | 619 | device_unregister(&devfreq->dev); |
3f19f08a AL |
620 | err_out: |
621 | return ERR_PTR(err); | |
a3c98b8b | 622 | } |
7e6fdd4b | 623 | EXPORT_SYMBOL(devfreq_add_device); |
a3c98b8b MH |
624 | |
625 | /** | |
626 | * devfreq_remove_device() - Remove devfreq feature from a device. | |
c5b4a1c1 | 627 | * @devfreq: the devfreq instance to be removed |
de9c7394 MH |
628 | * |
629 | * The opposite of devfreq_add_device(). | |
a3c98b8b MH |
630 | */ |
631 | int devfreq_remove_device(struct devfreq *devfreq) | |
632 | { | |
633 | if (!devfreq) | |
634 | return -EINVAL; | |
635 | ||
585fc83e | 636 | device_unregister(&devfreq->dev); |
9f3bdd4f | 637 | |
a3c98b8b MH |
638 | return 0; |
639 | } | |
7e6fdd4b | 640 | EXPORT_SYMBOL(devfreq_remove_device); |
a3c98b8b | 641 | |
8cd84092 CC |
642 | static int devm_devfreq_dev_match(struct device *dev, void *res, void *data) |
643 | { | |
644 | struct devfreq **r = res; | |
645 | ||
646 | if (WARN_ON(!r || !*r)) | |
647 | return 0; | |
648 | ||
649 | return *r == data; | |
650 | } | |
651 | ||
652 | static void devm_devfreq_dev_release(struct device *dev, void *res) | |
653 | { | |
654 | devfreq_remove_device(*(struct devfreq **)res); | |
655 | } | |
656 | ||
657 | /** | |
658 | * devm_devfreq_add_device() - Resource-managed devfreq_add_device() | |
659 | * @dev: the device to add devfreq feature. | |
660 | * @profile: device-specific profile to run devfreq. | |
661 | * @governor_name: name of the policy to choose frequency. | |
662 | * @data: private data for the governor. The devfreq framework does not | |
663 | * touch this value. | |
664 | * | |
665 | * This function manages automatically the memory of devfreq device using device | |
666 | * resource management and simplify the free operation for memory of devfreq | |
667 | * device. | |
668 | */ | |
669 | struct devfreq *devm_devfreq_add_device(struct device *dev, | |
670 | struct devfreq_dev_profile *profile, | |
671 | const char *governor_name, | |
672 | void *data) | |
673 | { | |
674 | struct devfreq **ptr, *devfreq; | |
675 | ||
676 | ptr = devres_alloc(devm_devfreq_dev_release, sizeof(*ptr), GFP_KERNEL); | |
677 | if (!ptr) | |
678 | return ERR_PTR(-ENOMEM); | |
679 | ||
680 | devfreq = devfreq_add_device(dev, profile, governor_name, data); | |
681 | if (IS_ERR(devfreq)) { | |
682 | devres_free(ptr); | |
683 | return ERR_PTR(-ENOMEM); | |
684 | } | |
685 | ||
686 | *ptr = devfreq; | |
687 | devres_add(dev, ptr); | |
688 | ||
689 | return devfreq; | |
690 | } | |
691 | EXPORT_SYMBOL(devm_devfreq_add_device); | |
692 | ||
8f510aeb CC |
693 | #ifdef CONFIG_OF |
694 | /* | |
695 | * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree | |
696 | * @dev - instance to the given device | |
697 | * @index - index into list of devfreq | |
698 | * | |
699 | * return the instance of devfreq device | |
700 | */ | |
701 | struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) | |
702 | { | |
703 | struct device_node *node; | |
704 | struct devfreq *devfreq; | |
705 | ||
706 | if (!dev) | |
707 | return ERR_PTR(-EINVAL); | |
708 | ||
709 | if (!dev->of_node) | |
710 | return ERR_PTR(-EINVAL); | |
711 | ||
712 | node = of_parse_phandle(dev->of_node, "devfreq", index); | |
713 | if (!node) | |
714 | return ERR_PTR(-ENODEV); | |
715 | ||
716 | mutex_lock(&devfreq_list_lock); | |
717 | list_for_each_entry(devfreq, &devfreq_list, node) { | |
718 | if (devfreq->dev.parent | |
719 | && devfreq->dev.parent->of_node == node) { | |
720 | mutex_unlock(&devfreq_list_lock); | |
3427c6f0 | 721 | of_node_put(node); |
8f510aeb CC |
722 | return devfreq; |
723 | } | |
724 | } | |
725 | mutex_unlock(&devfreq_list_lock); | |
3427c6f0 | 726 | of_node_put(node); |
8f510aeb CC |
727 | |
728 | return ERR_PTR(-EPROBE_DEFER); | |
729 | } | |
730 | #else | |
731 | struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) | |
732 | { | |
733 | return ERR_PTR(-ENODEV); | |
734 | } | |
735 | #endif /* CONFIG_OF */ | |
736 | EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle); | |
737 | ||
8cd84092 CC |
738 | /** |
739 | * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device() | |
740 | * @dev: the device to add devfreq feature. | |
741 | * @devfreq: the devfreq instance to be removed | |
742 | */ | |
743 | void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq) | |
744 | { | |
745 | WARN_ON(devres_release(dev, devm_devfreq_dev_release, | |
746 | devm_devfreq_dev_match, devfreq)); | |
747 | } | |
748 | EXPORT_SYMBOL(devm_devfreq_remove_device); | |
749 | ||
206c30cf RV |
750 | /** |
751 | * devfreq_suspend_device() - Suspend devfreq of a device. | |
752 | * @devfreq: the devfreq instance to be suspended | |
de9c7394 MH |
753 | * |
754 | * This function is intended to be called by the pm callbacks | |
755 | * (e.g., runtime_suspend, suspend) of the device driver that | |
756 | * holds the devfreq. | |
206c30cf RV |
757 | */ |
758 | int devfreq_suspend_device(struct devfreq *devfreq) | |
759 | { | |
a3c98b8b MH |
760 | if (!devfreq) |
761 | return -EINVAL; | |
762 | ||
1b5c1be2 NM |
763 | if (!devfreq->governor) |
764 | return 0; | |
765 | ||
206c30cf RV |
766 | return devfreq->governor->event_handler(devfreq, |
767 | DEVFREQ_GOV_SUSPEND, NULL); | |
768 | } | |
769 | EXPORT_SYMBOL(devfreq_suspend_device); | |
770 | ||
771 | /** | |
772 | * devfreq_resume_device() - Resume devfreq of a device. | |
773 | * @devfreq: the devfreq instance to be resumed | |
de9c7394 MH |
774 | * |
775 | * This function is intended to be called by the pm callbacks | |
776 | * (e.g., runtime_resume, resume) of the device driver that | |
777 | * holds the devfreq. | |
206c30cf RV |
778 | */ |
779 | int devfreq_resume_device(struct devfreq *devfreq) | |
780 | { | |
781 | if (!devfreq) | |
782 | return -EINVAL; | |
783 | ||
1b5c1be2 NM |
784 | if (!devfreq->governor) |
785 | return 0; | |
786 | ||
206c30cf RV |
787 | return devfreq->governor->event_handler(devfreq, |
788 | DEVFREQ_GOV_RESUME, NULL); | |
789 | } | |
790 | EXPORT_SYMBOL(devfreq_resume_device); | |
791 | ||
3aa173b8 NM |
792 | /** |
793 | * devfreq_add_governor() - Add devfreq governor | |
794 | * @governor: the devfreq governor to be added | |
795 | */ | |
796 | int devfreq_add_governor(struct devfreq_governor *governor) | |
797 | { | |
798 | struct devfreq_governor *g; | |
1b5c1be2 | 799 | struct devfreq *devfreq; |
3aa173b8 NM |
800 | int err = 0; |
801 | ||
802 | if (!governor) { | |
803 | pr_err("%s: Invalid parameters.\n", __func__); | |
804 | return -EINVAL; | |
805 | } | |
806 | ||
807 | mutex_lock(&devfreq_list_lock); | |
808 | g = find_devfreq_governor(governor->name); | |
809 | if (!IS_ERR(g)) { | |
810 | pr_err("%s: governor %s already registered\n", __func__, | |
811 | g->name); | |
812 | err = -EINVAL; | |
813 | goto err_out; | |
814 | } | |
9f3bdd4f | 815 | |
3aa173b8 NM |
816 | list_add(&governor->node, &devfreq_governor_list); |
817 | ||
1b5c1be2 NM |
818 | list_for_each_entry(devfreq, &devfreq_list, node) { |
819 | int ret = 0; | |
820 | struct device *dev = devfreq->dev.parent; | |
821 | ||
822 | if (!strncmp(devfreq->governor_name, governor->name, | |
823 | DEVFREQ_NAME_LEN)) { | |
824 | /* The following should never occur */ | |
825 | if (devfreq->governor) { | |
826 | dev_warn(dev, | |
827 | "%s: Governor %s already present\n", | |
828 | __func__, devfreq->governor->name); | |
829 | ret = devfreq->governor->event_handler(devfreq, | |
830 | DEVFREQ_GOV_STOP, NULL); | |
831 | if (ret) { | |
832 | dev_warn(dev, | |
833 | "%s: Governor %s stop = %d\n", | |
834 | __func__, | |
835 | devfreq->governor->name, ret); | |
836 | } | |
837 | /* Fall through */ | |
838 | } | |
839 | devfreq->governor = governor; | |
840 | ret = devfreq->governor->event_handler(devfreq, | |
841 | DEVFREQ_GOV_START, NULL); | |
842 | if (ret) { | |
843 | dev_warn(dev, "%s: Governor %s start=%d\n", | |
844 | __func__, devfreq->governor->name, | |
845 | ret); | |
846 | } | |
a3c98b8b MH |
847 | } |
848 | } | |
849 | ||
3aa173b8 NM |
850 | err_out: |
851 | mutex_unlock(&devfreq_list_lock); | |
a3c98b8b | 852 | |
3aa173b8 NM |
853 | return err; |
854 | } | |
855 | EXPORT_SYMBOL(devfreq_add_governor); | |
a3c98b8b | 856 | |
3aa173b8 | 857 | /** |
bafeb42b | 858 | * devfreq_remove_governor() - Remove devfreq feature from a device. |
3aa173b8 NM |
859 | * @governor: the devfreq governor to be removed |
860 | */ | |
861 | int devfreq_remove_governor(struct devfreq_governor *governor) | |
862 | { | |
863 | struct devfreq_governor *g; | |
1b5c1be2 | 864 | struct devfreq *devfreq; |
3aa173b8 NM |
865 | int err = 0; |
866 | ||
867 | if (!governor) { | |
868 | pr_err("%s: Invalid parameters.\n", __func__); | |
869 | return -EINVAL; | |
870 | } | |
871 | ||
872 | mutex_lock(&devfreq_list_lock); | |
873 | g = find_devfreq_governor(governor->name); | |
874 | if (IS_ERR(g)) { | |
875 | pr_err("%s: governor %s not registered\n", __func__, | |
b9e1c8e8 | 876 | governor->name); |
f9c08e2a | 877 | err = PTR_ERR(g); |
3aa173b8 NM |
878 | goto err_out; |
879 | } | |
1b5c1be2 NM |
880 | list_for_each_entry(devfreq, &devfreq_list, node) { |
881 | int ret; | |
882 | struct device *dev = devfreq->dev.parent; | |
883 | ||
884 | if (!strncmp(devfreq->governor_name, governor->name, | |
885 | DEVFREQ_NAME_LEN)) { | |
886 | /* we should have a devfreq governor! */ | |
887 | if (!devfreq->governor) { | |
888 | dev_warn(dev, "%s: Governor %s NOT present\n", | |
889 | __func__, governor->name); | |
890 | continue; | |
891 | /* Fall through */ | |
892 | } | |
893 | ret = devfreq->governor->event_handler(devfreq, | |
894 | DEVFREQ_GOV_STOP, NULL); | |
895 | if (ret) { | |
896 | dev_warn(dev, "%s: Governor %s stop=%d\n", | |
897 | __func__, devfreq->governor->name, | |
898 | ret); | |
899 | } | |
900 | devfreq->governor = NULL; | |
901 | } | |
902 | } | |
3aa173b8 NM |
903 | |
904 | list_del(&governor->node); | |
905 | err_out: | |
906 | mutex_unlock(&devfreq_list_lock); | |
907 | ||
908 | return err; | |
a3c98b8b | 909 | } |
3aa173b8 | 910 | EXPORT_SYMBOL(devfreq_remove_governor); |
a3c98b8b | 911 | |
a93d6b0a | 912 | static ssize_t governor_show(struct device *dev, |
9005b650 MH |
913 | struct device_attribute *attr, char *buf) |
914 | { | |
1b5c1be2 NM |
915 | if (!to_devfreq(dev)->governor) |
916 | return -EINVAL; | |
917 | ||
9005b650 MH |
918 | return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name); |
919 | } | |
920 | ||
a93d6b0a | 921 | static ssize_t governor_store(struct device *dev, struct device_attribute *attr, |
0359d1af NM |
922 | const char *buf, size_t count) |
923 | { | |
924 | struct devfreq *df = to_devfreq(dev); | |
925 | int ret; | |
926 | char str_governor[DEVFREQ_NAME_LEN + 1]; | |
927 | struct devfreq_governor *governor; | |
928 | ||
929 | ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor); | |
930 | if (ret != 1) | |
931 | return -EINVAL; | |
932 | ||
933 | mutex_lock(&devfreq_list_lock); | |
934 | governor = find_devfreq_governor(str_governor); | |
935 | if (IS_ERR(governor)) { | |
936 | ret = PTR_ERR(governor); | |
937 | goto out; | |
938 | } | |
14a21e7b TJ |
939 | if (df->governor == governor) { |
940 | ret = 0; | |
0359d1af | 941 | goto out; |
14a21e7b | 942 | } |
0359d1af NM |
943 | |
944 | if (df->governor) { | |
945 | ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL); | |
946 | if (ret) { | |
947 | dev_warn(dev, "%s: Governor %s not stopped(%d)\n", | |
948 | __func__, df->governor->name, ret); | |
949 | goto out; | |
950 | } | |
951 | } | |
952 | df->governor = governor; | |
953 | strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN); | |
954 | ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL); | |
955 | if (ret) | |
956 | dev_warn(dev, "%s: Governor %s not started(%d)\n", | |
957 | __func__, df->governor->name, ret); | |
958 | out: | |
959 | mutex_unlock(&devfreq_list_lock); | |
960 | ||
961 | if (!ret) | |
962 | ret = count; | |
963 | return ret; | |
964 | } | |
a93d6b0a GKH |
965 | static DEVICE_ATTR_RW(governor); |
966 | ||
967 | static ssize_t available_governors_show(struct device *d, | |
968 | struct device_attribute *attr, | |
969 | char *buf) | |
50a5b33e NM |
970 | { |
971 | struct devfreq_governor *tmp_governor; | |
972 | ssize_t count = 0; | |
973 | ||
974 | mutex_lock(&devfreq_list_lock); | |
975 | list_for_each_entry(tmp_governor, &devfreq_governor_list, node) | |
976 | count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), | |
977 | "%s ", tmp_governor->name); | |
978 | mutex_unlock(&devfreq_list_lock); | |
979 | ||
980 | /* Truncate the trailing space */ | |
981 | if (count) | |
982 | count--; | |
983 | ||
984 | count += sprintf(&buf[count], "\n"); | |
985 | ||
986 | return count; | |
987 | } | |
a93d6b0a | 988 | static DEVICE_ATTR_RO(available_governors); |
0359d1af | 989 | |
a93d6b0a GKH |
990 | static ssize_t cur_freq_show(struct device *dev, struct device_attribute *attr, |
991 | char *buf) | |
7f98a905 RV |
992 | { |
993 | unsigned long freq; | |
994 | struct devfreq *devfreq = to_devfreq(dev); | |
995 | ||
996 | if (devfreq->profile->get_cur_freq && | |
997 | !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) | |
998 | return sprintf(buf, "%lu\n", freq); | |
999 | ||
1000 | return sprintf(buf, "%lu\n", devfreq->previous_freq); | |
1001 | } | |
a93d6b0a | 1002 | static DEVICE_ATTR_RO(cur_freq); |
7f98a905 | 1003 | |
a93d6b0a GKH |
1004 | static ssize_t target_freq_show(struct device *dev, |
1005 | struct device_attribute *attr, char *buf) | |
9005b650 MH |
1006 | { |
1007 | return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq); | |
1008 | } | |
a93d6b0a | 1009 | static DEVICE_ATTR_RO(target_freq); |
9005b650 | 1010 | |
a93d6b0a | 1011 | static ssize_t polling_interval_show(struct device *dev, |
9005b650 MH |
1012 | struct device_attribute *attr, char *buf) |
1013 | { | |
1014 | return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms); | |
1015 | } | |
1016 | ||
a93d6b0a | 1017 | static ssize_t polling_interval_store(struct device *dev, |
9005b650 MH |
1018 | struct device_attribute *attr, |
1019 | const char *buf, size_t count) | |
1020 | { | |
1021 | struct devfreq *df = to_devfreq(dev); | |
1022 | unsigned int value; | |
1023 | int ret; | |
1024 | ||
1b5c1be2 NM |
1025 | if (!df->governor) |
1026 | return -EINVAL; | |
1027 | ||
9005b650 MH |
1028 | ret = sscanf(buf, "%u", &value); |
1029 | if (ret != 1) | |
12e26265 | 1030 | return -EINVAL; |
9005b650 | 1031 | |
7e6fdd4b | 1032 | df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL, &value); |
9005b650 MH |
1033 | ret = count; |
1034 | ||
9005b650 MH |
1035 | return ret; |
1036 | } | |
a93d6b0a | 1037 | static DEVICE_ATTR_RW(polling_interval); |
9005b650 | 1038 | |
a93d6b0a | 1039 | static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, |
6530b9de MH |
1040 | const char *buf, size_t count) |
1041 | { | |
1042 | struct devfreq *df = to_devfreq(dev); | |
1043 | unsigned long value; | |
1044 | int ret; | |
1045 | unsigned long max; | |
1046 | ||
1047 | ret = sscanf(buf, "%lu", &value); | |
1048 | if (ret != 1) | |
12e26265 | 1049 | return -EINVAL; |
6530b9de MH |
1050 | |
1051 | mutex_lock(&df->lock); | |
1052 | max = df->max_freq; | |
1053 | if (value && max && value > max) { | |
1054 | ret = -EINVAL; | |
1055 | goto unlock; | |
1056 | } | |
1057 | ||
1058 | df->min_freq = value; | |
1059 | update_devfreq(df); | |
1060 | ret = count; | |
1061 | unlock: | |
1062 | mutex_unlock(&df->lock); | |
6530b9de MH |
1063 | return ret; |
1064 | } | |
1065 | ||
a93d6b0a | 1066 | static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, |
6530b9de MH |
1067 | const char *buf, size_t count) |
1068 | { | |
1069 | struct devfreq *df = to_devfreq(dev); | |
1070 | unsigned long value; | |
1071 | int ret; | |
1072 | unsigned long min; | |
1073 | ||
1074 | ret = sscanf(buf, "%lu", &value); | |
1075 | if (ret != 1) | |
12e26265 | 1076 | return -EINVAL; |
6530b9de MH |
1077 | |
1078 | mutex_lock(&df->lock); | |
1079 | min = df->min_freq; | |
1080 | if (value && min && value < min) { | |
1081 | ret = -EINVAL; | |
1082 | goto unlock; | |
1083 | } | |
1084 | ||
1085 | df->max_freq = value; | |
1086 | update_devfreq(df); | |
1087 | ret = count; | |
1088 | unlock: | |
1089 | mutex_unlock(&df->lock); | |
6530b9de MH |
1090 | return ret; |
1091 | } | |
1092 | ||
3104fa30 CC |
1093 | #define show_one(name) \ |
1094 | static ssize_t name##_show \ | |
1095 | (struct device *dev, struct device_attribute *attr, char *buf) \ | |
1096 | { \ | |
1097 | return sprintf(buf, "%lu\n", to_devfreq(dev)->name); \ | |
6530b9de | 1098 | } |
3104fa30 CC |
1099 | show_one(min_freq); |
1100 | show_one(max_freq); | |
1101 | ||
1102 | static DEVICE_ATTR_RW(min_freq); | |
a93d6b0a | 1103 | static DEVICE_ATTR_RW(max_freq); |
6530b9de | 1104 | |
a93d6b0a GKH |
1105 | static ssize_t available_frequencies_show(struct device *d, |
1106 | struct device_attribute *attr, | |
1107 | char *buf) | |
d287de85 NM |
1108 | { |
1109 | struct devfreq *df = to_devfreq(d); | |
1110 | struct device *dev = df->dev.parent; | |
47d43ba7 | 1111 | struct dev_pm_opp *opp; |
d287de85 NM |
1112 | ssize_t count = 0; |
1113 | unsigned long freq = 0; | |
1114 | ||
1115 | rcu_read_lock(); | |
1116 | do { | |
5d4879cd | 1117 | opp = dev_pm_opp_find_freq_ceil(dev, &freq); |
d287de85 NM |
1118 | if (IS_ERR(opp)) |
1119 | break; | |
1120 | ||
1121 | count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), | |
1122 | "%lu ", freq); | |
1123 | freq++; | |
1124 | } while (1); | |
1125 | rcu_read_unlock(); | |
1126 | ||
1127 | /* Truncate the trailing space */ | |
1128 | if (count) | |
1129 | count--; | |
1130 | ||
1131 | count += sprintf(&buf[count], "\n"); | |
1132 | ||
1133 | return count; | |
1134 | } | |
a93d6b0a | 1135 | static DEVICE_ATTR_RO(available_frequencies); |
d287de85 | 1136 | |
a93d6b0a GKH |
1137 | static ssize_t trans_stat_show(struct device *dev, |
1138 | struct device_attribute *attr, char *buf) | |
e552bbaf JL |
1139 | { |
1140 | struct devfreq *devfreq = to_devfreq(dev); | |
1141 | ssize_t len; | |
39688ce6 | 1142 | int i, j; |
e552bbaf JL |
1143 | unsigned int max_state = devfreq->profile->max_state; |
1144 | ||
39688ce6 RV |
1145 | if (!devfreq->stop_polling && |
1146 | devfreq_update_status(devfreq, devfreq->previous_freq)) | |
e552bbaf | 1147 | return 0; |
34bd3220 MH |
1148 | if (max_state == 0) |
1149 | return sprintf(buf, "Not Supported.\n"); | |
e552bbaf | 1150 | |
d7df1e46 CC |
1151 | len = sprintf(buf, " From : To\n"); |
1152 | len += sprintf(buf + len, " :"); | |
e552bbaf | 1153 | for (i = 0; i < max_state; i++) |
d7df1e46 | 1154 | len += sprintf(buf + len, "%10lu", |
e552bbaf JL |
1155 | devfreq->profile->freq_table[i]); |
1156 | ||
1157 | len += sprintf(buf + len, " time(ms)\n"); | |
1158 | ||
1159 | for (i = 0; i < max_state; i++) { | |
1160 | if (devfreq->profile->freq_table[i] | |
1161 | == devfreq->previous_freq) { | |
1162 | len += sprintf(buf + len, "*"); | |
1163 | } else { | |
1164 | len += sprintf(buf + len, " "); | |
1165 | } | |
d7df1e46 | 1166 | len += sprintf(buf + len, "%10lu:", |
e552bbaf JL |
1167 | devfreq->profile->freq_table[i]); |
1168 | for (j = 0; j < max_state; j++) | |
d7df1e46 | 1169 | len += sprintf(buf + len, "%10u", |
e552bbaf JL |
1170 | devfreq->trans_table[(i * max_state) + j]); |
1171 | len += sprintf(buf + len, "%10u\n", | |
1172 | jiffies_to_msecs(devfreq->time_in_state[i])); | |
1173 | } | |
1174 | ||
1175 | len += sprintf(buf + len, "Total transition : %u\n", | |
1176 | devfreq->total_trans); | |
1177 | return len; | |
1178 | } | |
a93d6b0a GKH |
1179 | static DEVICE_ATTR_RO(trans_stat); |
1180 | ||
1181 | static struct attribute *devfreq_attrs[] = { | |
1182 | &dev_attr_governor.attr, | |
1183 | &dev_attr_available_governors.attr, | |
1184 | &dev_attr_cur_freq.attr, | |
1185 | &dev_attr_available_frequencies.attr, | |
1186 | &dev_attr_target_freq.attr, | |
1187 | &dev_attr_polling_interval.attr, | |
1188 | &dev_attr_min_freq.attr, | |
1189 | &dev_attr_max_freq.attr, | |
1190 | &dev_attr_trans_stat.attr, | |
1191 | NULL, | |
9005b650 | 1192 | }; |
a93d6b0a | 1193 | ATTRIBUTE_GROUPS(devfreq); |
9005b650 | 1194 | |
a3c98b8b MH |
1195 | static int __init devfreq_init(void) |
1196 | { | |
1197 | devfreq_class = class_create(THIS_MODULE, "devfreq"); | |
1198 | if (IS_ERR(devfreq_class)) { | |
1199 | pr_err("%s: couldn't create class\n", __FILE__); | |
1200 | return PTR_ERR(devfreq_class); | |
1201 | } | |
7e6fdd4b RV |
1202 | |
1203 | devfreq_wq = create_freezable_workqueue("devfreq_wq"); | |
ea7f4548 | 1204 | if (!devfreq_wq) { |
7e6fdd4b RV |
1205 | class_destroy(devfreq_class); |
1206 | pr_err("%s: couldn't create workqueue\n", __FILE__); | |
ea7f4548 | 1207 | return -ENOMEM; |
7e6fdd4b | 1208 | } |
a93d6b0a | 1209 | devfreq_class->dev_groups = devfreq_groups; |
7e6fdd4b | 1210 | |
a3c98b8b MH |
1211 | return 0; |
1212 | } | |
1213 | subsys_initcall(devfreq_init); | |
1214 | ||
a3c98b8b MH |
1215 | /* |
1216 | * The followings are helper functions for devfreq user device drivers with | |
1217 | * OPP framework. | |
1218 | */ | |
1219 | ||
1220 | /** | |
1221 | * devfreq_recommended_opp() - Helper function to get proper OPP for the | |
1222 | * freq value given to target callback. | |
c5b4a1c1 NM |
1223 | * @dev: The devfreq user device. (parent of devfreq) |
1224 | * @freq: The frequency given to target function | |
1225 | * @flags: Flags handed from devfreq framework. | |
a3c98b8b | 1226 | * |
bcb27549 NM |
1227 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
1228 | * protected pointer. The reason for the same is that the opp pointer which is | |
1229 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
1230 | * under the locked area. The pointer returned must be used prior to unlocking | |
1231 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
a3c98b8b | 1232 | */ |
47d43ba7 NM |
1233 | struct dev_pm_opp *devfreq_recommended_opp(struct device *dev, |
1234 | unsigned long *freq, | |
1235 | u32 flags) | |
a3c98b8b | 1236 | { |
47d43ba7 | 1237 | struct dev_pm_opp *opp; |
a3c98b8b | 1238 | |
ab5f299f MH |
1239 | if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) { |
1240 | /* The freq is an upper bound. opp should be lower */ | |
5d4879cd | 1241 | opp = dev_pm_opp_find_freq_floor(dev, freq); |
ab5f299f MH |
1242 | |
1243 | /* If not available, use the closest opp */ | |
0779726c | 1244 | if (opp == ERR_PTR(-ERANGE)) |
5d4879cd | 1245 | opp = dev_pm_opp_find_freq_ceil(dev, freq); |
ab5f299f MH |
1246 | } else { |
1247 | /* The freq is an lower bound. opp should be higher */ | |
5d4879cd | 1248 | opp = dev_pm_opp_find_freq_ceil(dev, freq); |
ab5f299f MH |
1249 | |
1250 | /* If not available, use the closest opp */ | |
0779726c | 1251 | if (opp == ERR_PTR(-ERANGE)) |
5d4879cd | 1252 | opp = dev_pm_opp_find_freq_floor(dev, freq); |
ab5f299f MH |
1253 | } |
1254 | ||
a3c98b8b MH |
1255 | return opp; |
1256 | } | |
bd7e9277 | 1257 | EXPORT_SYMBOL(devfreq_recommended_opp); |
a3c98b8b MH |
1258 | |
1259 | /** | |
1260 | * devfreq_register_opp_notifier() - Helper function to get devfreq notified | |
1261 | * for any changes in the OPP availability | |
1262 | * changes | |
c5b4a1c1 NM |
1263 | * @dev: The devfreq user device. (parent of devfreq) |
1264 | * @devfreq: The devfreq object. | |
a3c98b8b MH |
1265 | */ |
1266 | int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) | |
1267 | { | |
389baed0 MH |
1268 | struct srcu_notifier_head *nh; |
1269 | int ret = 0; | |
a3c98b8b | 1270 | |
389baed0 | 1271 | rcu_read_lock(); |
5d4879cd | 1272 | nh = dev_pm_opp_get_notifier(dev); |
a3c98b8b | 1273 | if (IS_ERR(nh)) |
389baed0 MH |
1274 | ret = PTR_ERR(nh); |
1275 | rcu_read_unlock(); | |
1276 | if (!ret) | |
1277 | ret = srcu_notifier_chain_register(nh, &devfreq->nb); | |
1278 | ||
1279 | return ret; | |
a3c98b8b | 1280 | } |
bd7e9277 | 1281 | EXPORT_SYMBOL(devfreq_register_opp_notifier); |
a3c98b8b MH |
1282 | |
1283 | /** | |
1284 | * devfreq_unregister_opp_notifier() - Helper function to stop getting devfreq | |
1285 | * notified for any changes in the OPP | |
1286 | * availability changes anymore. | |
c5b4a1c1 NM |
1287 | * @dev: The devfreq user device. (parent of devfreq) |
1288 | * @devfreq: The devfreq object. | |
a3c98b8b MH |
1289 | * |
1290 | * At exit() callback of devfreq_dev_profile, this must be included if | |
1291 | * devfreq_recommended_opp is used. | |
1292 | */ | |
1293 | int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) | |
1294 | { | |
389baed0 MH |
1295 | struct srcu_notifier_head *nh; |
1296 | int ret = 0; | |
a3c98b8b | 1297 | |
389baed0 | 1298 | rcu_read_lock(); |
5d4879cd | 1299 | nh = dev_pm_opp_get_notifier(dev); |
a3c98b8b | 1300 | if (IS_ERR(nh)) |
389baed0 MH |
1301 | ret = PTR_ERR(nh); |
1302 | rcu_read_unlock(); | |
1303 | if (!ret) | |
1304 | ret = srcu_notifier_chain_unregister(nh, &devfreq->nb); | |
1305 | ||
1306 | return ret; | |
a3c98b8b | 1307 | } |
bd7e9277 | 1308 | EXPORT_SYMBOL(devfreq_unregister_opp_notifier); |
a3c98b8b | 1309 | |
d5b040d0 CC |
1310 | static void devm_devfreq_opp_release(struct device *dev, void *res) |
1311 | { | |
1312 | devfreq_unregister_opp_notifier(dev, *(struct devfreq **)res); | |
1313 | } | |
1314 | ||
1315 | /** | |
1316 | * devm_ devfreq_register_opp_notifier() | |
1317 | * - Resource-managed devfreq_register_opp_notifier() | |
1318 | * @dev: The devfreq user device. (parent of devfreq) | |
1319 | * @devfreq: The devfreq object. | |
1320 | */ | |
1321 | int devm_devfreq_register_opp_notifier(struct device *dev, | |
1322 | struct devfreq *devfreq) | |
1323 | { | |
1324 | struct devfreq **ptr; | |
1325 | int ret; | |
1326 | ||
1327 | ptr = devres_alloc(devm_devfreq_opp_release, sizeof(*ptr), GFP_KERNEL); | |
1328 | if (!ptr) | |
1329 | return -ENOMEM; | |
1330 | ||
1331 | ret = devfreq_register_opp_notifier(dev, devfreq); | |
1332 | if (ret) { | |
1333 | devres_free(ptr); | |
1334 | return ret; | |
1335 | } | |
1336 | ||
1337 | *ptr = devfreq; | |
1338 | devres_add(dev, ptr); | |
1339 | ||
1340 | return 0; | |
1341 | } | |
1342 | EXPORT_SYMBOL(devm_devfreq_register_opp_notifier); | |
1343 | ||
1344 | /** | |
1345 | * devm_devfreq_unregister_opp_notifier() | |
1346 | * - Resource-managed devfreq_unregister_opp_notifier() | |
1347 | * @dev: The devfreq user device. (parent of devfreq) | |
1348 | * @devfreq: The devfreq object. | |
1349 | */ | |
1350 | void devm_devfreq_unregister_opp_notifier(struct device *dev, | |
1351 | struct devfreq *devfreq) | |
1352 | { | |
1353 | WARN_ON(devres_release(dev, devm_devfreq_opp_release, | |
1354 | devm_devfreq_dev_match, devfreq)); | |
1355 | } | |
1356 | EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier); | |
1357 | ||
0fe3a664 CC |
1358 | /** |
1359 | * devfreq_register_notifier() - Register a driver with devfreq | |
1360 | * @devfreq: The devfreq object. | |
1361 | * @nb: The notifier block to register. | |
1362 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1363 | */ | |
1364 | int devfreq_register_notifier(struct devfreq *devfreq, | |
1365 | struct notifier_block *nb, | |
1366 | unsigned int list) | |
1367 | { | |
1368 | int ret = 0; | |
1369 | ||
1370 | if (!devfreq) | |
1371 | return -EINVAL; | |
1372 | ||
1373 | switch (list) { | |
1374 | case DEVFREQ_TRANSITION_NOTIFIER: | |
1375 | ret = srcu_notifier_chain_register( | |
1376 | &devfreq->transition_notifier_list, nb); | |
1377 | break; | |
1378 | default: | |
1379 | ret = -EINVAL; | |
1380 | } | |
1381 | ||
1382 | return ret; | |
1383 | } | |
1384 | EXPORT_SYMBOL(devfreq_register_notifier); | |
1385 | ||
1386 | /* | |
1387 | * devfreq_unregister_notifier() - Unregister a driver with devfreq | |
1388 | * @devfreq: The devfreq object. | |
1389 | * @nb: The notifier block to be unregistered. | |
1390 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1391 | */ | |
1392 | int devfreq_unregister_notifier(struct devfreq *devfreq, | |
1393 | struct notifier_block *nb, | |
1394 | unsigned int list) | |
1395 | { | |
1396 | int ret = 0; | |
1397 | ||
1398 | if (!devfreq) | |
1399 | return -EINVAL; | |
1400 | ||
1401 | switch (list) { | |
1402 | case DEVFREQ_TRANSITION_NOTIFIER: | |
1403 | ret = srcu_notifier_chain_unregister( | |
1404 | &devfreq->transition_notifier_list, nb); | |
1405 | break; | |
1406 | default: | |
1407 | ret = -EINVAL; | |
1408 | } | |
1409 | ||
1410 | return ret; | |
1411 | } | |
1412 | EXPORT_SYMBOL(devfreq_unregister_notifier); | |
1413 | ||
1414 | struct devfreq_notifier_devres { | |
1415 | struct devfreq *devfreq; | |
1416 | struct notifier_block *nb; | |
1417 | unsigned int list; | |
1418 | }; | |
1419 | ||
1420 | static void devm_devfreq_notifier_release(struct device *dev, void *res) | |
1421 | { | |
1422 | struct devfreq_notifier_devres *this = res; | |
1423 | ||
1424 | devfreq_unregister_notifier(this->devfreq, this->nb, this->list); | |
1425 | } | |
1426 | ||
1427 | /** | |
1428 | * devm_devfreq_register_notifier() | |
1429 | - Resource-managed devfreq_register_notifier() | |
1430 | * @dev: The devfreq user device. (parent of devfreq) | |
1431 | * @devfreq: The devfreq object. | |
1432 | * @nb: The notifier block to be unregistered. | |
1433 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1434 | */ | |
1435 | int devm_devfreq_register_notifier(struct device *dev, | |
1436 | struct devfreq *devfreq, | |
1437 | struct notifier_block *nb, | |
1438 | unsigned int list) | |
1439 | { | |
1440 | struct devfreq_notifier_devres *ptr; | |
1441 | int ret; | |
1442 | ||
1443 | ptr = devres_alloc(devm_devfreq_notifier_release, sizeof(*ptr), | |
1444 | GFP_KERNEL); | |
1445 | if (!ptr) | |
1446 | return -ENOMEM; | |
1447 | ||
1448 | ret = devfreq_register_notifier(devfreq, nb, list); | |
1449 | if (ret) { | |
1450 | devres_free(ptr); | |
1451 | return ret; | |
1452 | } | |
1453 | ||
1454 | ptr->devfreq = devfreq; | |
1455 | ptr->nb = nb; | |
1456 | ptr->list = list; | |
1457 | devres_add(dev, ptr); | |
1458 | ||
1459 | return 0; | |
1460 | } | |
1461 | EXPORT_SYMBOL(devm_devfreq_register_notifier); | |
1462 | ||
1463 | /** | |
1464 | * devm_devfreq_unregister_notifier() | |
1465 | - Resource-managed devfreq_unregister_notifier() | |
1466 | * @dev: The devfreq user device. (parent of devfreq) | |
1467 | * @devfreq: The devfreq object. | |
1468 | * @nb: The notifier block to be unregistered. | |
1469 | * @list: DEVFREQ_TRANSITION_NOTIFIER. | |
1470 | */ | |
1471 | void devm_devfreq_unregister_notifier(struct device *dev, | |
1472 | struct devfreq *devfreq, | |
1473 | struct notifier_block *nb, | |
1474 | unsigned int list) | |
1475 | { | |
1476 | WARN_ON(devres_release(dev, devm_devfreq_notifier_release, | |
1477 | devm_devfreq_dev_match, devfreq)); | |
1478 | } | |
1479 | EXPORT_SYMBOL(devm_devfreq_unregister_notifier); |