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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic OPP Interface
4  *
5  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
6  *	Nishanth Menon
7  *	Romit Dasgupta
8  *	Kevin Hilman
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/clk.h>
14 #include <linux/errno.h>
15 #include <linux/err.h>
16 #include <linux/slab.h>
17 #include <linux/device.h>
18 #include <linux/export.h>
19 #include <linux/pm_domain.h>
20 #include <linux/regulator/consumer.h>
21 
22 #include "opp.h"
23 
24 /*
25  * The root of the list of all opp-tables. All opp_table structures branch off
26  * from here, with each opp_table containing the list of opps it supports in
27  * various states of availability.
28  */
29 LIST_HEAD(opp_tables);
30 
31 /* OPP tables with uninitialized required OPPs */
32 LIST_HEAD(lazy_opp_tables);
33 
34 /* Lock to allow exclusive modification to the device and opp lists */
35 DEFINE_MUTEX(opp_table_lock);
36 /* Flag indicating that opp_tables list is being updated at the moment */
37 static bool opp_tables_busy;
38 
_find_opp_dev(const struct device * dev,struct opp_table * opp_table)39 static bool _find_opp_dev(const struct device *dev, struct opp_table *opp_table)
40 {
41 	struct opp_device *opp_dev;
42 	bool found = false;
43 
44 	mutex_lock(&opp_table->lock);
45 	list_for_each_entry(opp_dev, &opp_table->dev_list, node)
46 		if (opp_dev->dev == dev) {
47 			found = true;
48 			break;
49 		}
50 
51 	mutex_unlock(&opp_table->lock);
52 	return found;
53 }
54 
_find_opp_table_unlocked(struct device * dev)55 static struct opp_table *_find_opp_table_unlocked(struct device *dev)
56 {
57 	struct opp_table *opp_table;
58 
59 	list_for_each_entry(opp_table, &opp_tables, node) {
60 		if (_find_opp_dev(dev, opp_table)) {
61 			_get_opp_table_kref(opp_table);
62 			return opp_table;
63 		}
64 	}
65 
66 	return ERR_PTR(-ENODEV);
67 }
68 
69 /**
70  * _find_opp_table() - find opp_table struct using device pointer
71  * @dev:	device pointer used to lookup OPP table
72  *
73  * Search OPP table for one containing matching device.
74  *
75  * Return: pointer to 'struct opp_table' if found, otherwise -ENODEV or
76  * -EINVAL based on type of error.
77  *
78  * The callers must call dev_pm_opp_put_opp_table() after the table is used.
79  */
_find_opp_table(struct device * dev)80 struct opp_table *_find_opp_table(struct device *dev)
81 {
82 	struct opp_table *opp_table;
83 
84 	if (IS_ERR_OR_NULL(dev)) {
85 		pr_err("%s: Invalid parameters\n", __func__);
86 		return ERR_PTR(-EINVAL);
87 	}
88 
89 	mutex_lock(&opp_table_lock);
90 	opp_table = _find_opp_table_unlocked(dev);
91 	mutex_unlock(&opp_table_lock);
92 
93 	return opp_table;
94 }
95 
96 /**
97  * dev_pm_opp_get_voltage() - Gets the voltage corresponding to an opp
98  * @opp:	opp for which voltage has to be returned for
99  *
100  * Return: voltage in micro volt corresponding to the opp, else
101  * return 0
102  *
103  * This is useful only for devices with single power supply.
104  */
dev_pm_opp_get_voltage(struct dev_pm_opp * opp)105 unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
106 {
107 	if (IS_ERR_OR_NULL(opp)) {
108 		pr_err("%s: Invalid parameters\n", __func__);
109 		return 0;
110 	}
111 
112 	return opp->supplies[0].u_volt;
113 }
114 EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage);
115 
116 /**
117  * dev_pm_opp_get_freq() - Gets the frequency corresponding to an available opp
118  * @opp:	opp for which frequency has to be returned for
119  *
120  * Return: frequency in hertz corresponding to the opp, else
121  * return 0
122  */
dev_pm_opp_get_freq(struct dev_pm_opp * opp)123 unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp)
124 {
125 	if (IS_ERR_OR_NULL(opp)) {
126 		pr_err("%s: Invalid parameters\n", __func__);
127 		return 0;
128 	}
129 
130 	return opp->rate;
131 }
132 EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
133 
134 /**
135  * dev_pm_opp_get_level() - Gets the level corresponding to an available opp
136  * @opp:	opp for which level value has to be returned for
137  *
138  * Return: level read from device tree corresponding to the opp, else
139  * return 0.
140  */
dev_pm_opp_get_level(struct dev_pm_opp * opp)141 unsigned int dev_pm_opp_get_level(struct dev_pm_opp *opp)
142 {
143 	if (IS_ERR_OR_NULL(opp) || !opp->available) {
144 		pr_err("%s: Invalid parameters\n", __func__);
145 		return 0;
146 	}
147 
148 	return opp->level;
149 }
150 EXPORT_SYMBOL_GPL(dev_pm_opp_get_level);
151 
152 /**
153  * dev_pm_opp_get_required_pstate() - Gets the required performance state
154  *                                    corresponding to an available opp
155  * @opp:	opp for which performance state has to be returned for
156  * @index:	index of the required opp
157  *
158  * Return: performance state read from device tree corresponding to the
159  * required opp, else return 0.
160  */
dev_pm_opp_get_required_pstate(struct dev_pm_opp * opp,unsigned int index)161 unsigned int dev_pm_opp_get_required_pstate(struct dev_pm_opp *opp,
162 					    unsigned int index)
163 {
164 	if (IS_ERR_OR_NULL(opp) || !opp->available ||
165 	    index >= opp->opp_table->required_opp_count) {
166 		pr_err("%s: Invalid parameters\n", __func__);
167 		return 0;
168 	}
169 
170 	/* required-opps not fully initialized yet */
171 	if (lazy_linking_pending(opp->opp_table))
172 		return 0;
173 
174 	return opp->required_opps[index]->pstate;
175 }
176 EXPORT_SYMBOL_GPL(dev_pm_opp_get_required_pstate);
177 
178 /**
179  * dev_pm_opp_is_turbo() - Returns if opp is turbo OPP or not
180  * @opp: opp for which turbo mode is being verified
181  *
182  * Turbo OPPs are not for normal use, and can be enabled (under certain
183  * conditions) for short duration of times to finish high throughput work
184  * quickly. Running on them for longer times may overheat the chip.
185  *
186  * Return: true if opp is turbo opp, else false.
187  */
dev_pm_opp_is_turbo(struct dev_pm_opp * opp)188 bool dev_pm_opp_is_turbo(struct dev_pm_opp *opp)
189 {
190 	if (IS_ERR_OR_NULL(opp) || !opp->available) {
191 		pr_err("%s: Invalid parameters\n", __func__);
192 		return false;
193 	}
194 
195 	return opp->turbo;
196 }
197 EXPORT_SYMBOL_GPL(dev_pm_opp_is_turbo);
198 
199 /**
200  * dev_pm_opp_get_max_clock_latency() - Get max clock latency in nanoseconds
201  * @dev:	device for which we do this operation
202  *
203  * Return: This function returns the max clock latency in nanoseconds.
204  */
dev_pm_opp_get_max_clock_latency(struct device * dev)205 unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev)
206 {
207 	struct opp_table *opp_table;
208 	unsigned long clock_latency_ns;
209 
210 	opp_table = _find_opp_table(dev);
211 	if (IS_ERR(opp_table))
212 		return 0;
213 
214 	clock_latency_ns = opp_table->clock_latency_ns_max;
215 
216 	dev_pm_opp_put_opp_table(opp_table);
217 
218 	return clock_latency_ns;
219 }
220 EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency);
221 
222 /**
223  * dev_pm_opp_get_max_volt_latency() - Get max voltage latency in nanoseconds
224  * @dev: device for which we do this operation
225  *
226  * Return: This function returns the max voltage latency in nanoseconds.
227  */
dev_pm_opp_get_max_volt_latency(struct device * dev)228 unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev)
229 {
230 	struct opp_table *opp_table;
231 	struct dev_pm_opp *opp;
232 	struct regulator *reg;
233 	unsigned long latency_ns = 0;
234 	int ret, i, count;
235 	struct {
236 		unsigned long min;
237 		unsigned long max;
238 	} *uV;
239 
240 	opp_table = _find_opp_table(dev);
241 	if (IS_ERR(opp_table))
242 		return 0;
243 
244 	/* Regulator may not be required for the device */
245 	if (!opp_table->regulators)
246 		goto put_opp_table;
247 
248 	count = opp_table->regulator_count;
249 
250 	uV = kmalloc_array(count, sizeof(*uV), GFP_KERNEL);
251 	if (!uV)
252 		goto put_opp_table;
253 
254 	mutex_lock(&opp_table->lock);
255 
256 	for (i = 0; i < count; i++) {
257 		uV[i].min = ~0;
258 		uV[i].max = 0;
259 
260 		list_for_each_entry(opp, &opp_table->opp_list, node) {
261 			if (!opp->available)
262 				continue;
263 
264 			if (opp->supplies[i].u_volt_min < uV[i].min)
265 				uV[i].min = opp->supplies[i].u_volt_min;
266 			if (opp->supplies[i].u_volt_max > uV[i].max)
267 				uV[i].max = opp->supplies[i].u_volt_max;
268 		}
269 	}
270 
271 	mutex_unlock(&opp_table->lock);
272 
273 	/*
274 	 * The caller needs to ensure that opp_table (and hence the regulator)
275 	 * isn't freed, while we are executing this routine.
276 	 */
277 	for (i = 0; i < count; i++) {
278 		reg = opp_table->regulators[i];
279 		ret = regulator_set_voltage_time(reg, uV[i].min, uV[i].max);
280 		if (ret > 0)
281 			latency_ns += ret * 1000;
282 	}
283 
284 	kfree(uV);
285 put_opp_table:
286 	dev_pm_opp_put_opp_table(opp_table);
287 
288 	return latency_ns;
289 }
290 EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_volt_latency);
291 
292 /**
293  * dev_pm_opp_get_max_transition_latency() - Get max transition latency in
294  *					     nanoseconds
295  * @dev: device for which we do this operation
296  *
297  * Return: This function returns the max transition latency, in nanoseconds, to
298  * switch from one OPP to other.
299  */
dev_pm_opp_get_max_transition_latency(struct device * dev)300 unsigned long dev_pm_opp_get_max_transition_latency(struct device *dev)
301 {
302 	return dev_pm_opp_get_max_volt_latency(dev) +
303 		dev_pm_opp_get_max_clock_latency(dev);
304 }
305 EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_transition_latency);
306 
307 /**
308  * dev_pm_opp_get_suspend_opp_freq() - Get frequency of suspend opp in Hz
309  * @dev:	device for which we do this operation
310  *
311  * Return: This function returns the frequency of the OPP marked as suspend_opp
312  * if one is available, else returns 0;
313  */
dev_pm_opp_get_suspend_opp_freq(struct device * dev)314 unsigned long dev_pm_opp_get_suspend_opp_freq(struct device *dev)
315 {
316 	struct opp_table *opp_table;
317 	unsigned long freq = 0;
318 
319 	opp_table = _find_opp_table(dev);
320 	if (IS_ERR(opp_table))
321 		return 0;
322 
323 	if (opp_table->suspend_opp && opp_table->suspend_opp->available)
324 		freq = dev_pm_opp_get_freq(opp_table->suspend_opp);
325 
326 	dev_pm_opp_put_opp_table(opp_table);
327 
328 	return freq;
329 }
330 EXPORT_SYMBOL_GPL(dev_pm_opp_get_suspend_opp_freq);
331 
_get_opp_count(struct opp_table * opp_table)332 int _get_opp_count(struct opp_table *opp_table)
333 {
334 	struct dev_pm_opp *opp;
335 	int count = 0;
336 
337 	mutex_lock(&opp_table->lock);
338 
339 	list_for_each_entry(opp, &opp_table->opp_list, node) {
340 		if (opp->available)
341 			count++;
342 	}
343 
344 	mutex_unlock(&opp_table->lock);
345 
346 	return count;
347 }
348 
349 /**
350  * dev_pm_opp_get_opp_count() - Get number of opps available in the opp table
351  * @dev:	device for which we do this operation
352  *
353  * Return: This function returns the number of available opps if there are any,
354  * else returns 0 if none or the corresponding error value.
355  */
dev_pm_opp_get_opp_count(struct device * dev)356 int dev_pm_opp_get_opp_count(struct device *dev)
357 {
358 	struct opp_table *opp_table;
359 	int count;
360 
361 	opp_table = _find_opp_table(dev);
362 	if (IS_ERR(opp_table)) {
363 		count = PTR_ERR(opp_table);
364 		dev_dbg(dev, "%s: OPP table not found (%d)\n",
365 			__func__, count);
366 		return count;
367 	}
368 
369 	count = _get_opp_count(opp_table);
370 	dev_pm_opp_put_opp_table(opp_table);
371 
372 	return count;
373 }
374 EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count);
375 
376 /**
377  * dev_pm_opp_find_freq_exact() - search for an exact frequency
378  * @dev:		device for which we do this operation
379  * @freq:		frequency to search for
380  * @available:		true/false - match for available opp
381  *
382  * Return: Searches for exact match in the opp table and returns pointer to the
383  * matching opp if found, else returns ERR_PTR in case of error and should
384  * be handled using IS_ERR. Error return values can be:
385  * EINVAL:	for bad pointer
386  * ERANGE:	no match found for search
387  * ENODEV:	if device not found in list of registered devices
388  *
389  * Note: available is a modifier for the search. if available=true, then the
390  * match is for exact matching frequency and is available in the stored OPP
391  * table. if false, the match is for exact frequency which is not available.
392  *
393  * This provides a mechanism to enable an opp which is not available currently
394  * or the opposite as well.
395  *
396  * The callers are required to call dev_pm_opp_put() for the returned OPP after
397  * use.
398  */
dev_pm_opp_find_freq_exact(struct device * dev,unsigned long freq,bool available)399 struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
400 					      unsigned long freq,
401 					      bool available)
402 {
403 	struct opp_table *opp_table;
404 	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
405 
406 	opp_table = _find_opp_table(dev);
407 	if (IS_ERR(opp_table)) {
408 		int r = PTR_ERR(opp_table);
409 
410 		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, r);
411 		return ERR_PTR(r);
412 	}
413 
414 	mutex_lock(&opp_table->lock);
415 
416 	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
417 		if (temp_opp->available == available &&
418 				temp_opp->rate == freq) {
419 			opp = temp_opp;
420 
421 			/* Increment the reference count of OPP */
422 			dev_pm_opp_get(opp);
423 			break;
424 		}
425 	}
426 
427 	mutex_unlock(&opp_table->lock);
428 	dev_pm_opp_put_opp_table(opp_table);
429 
430 	return opp;
431 }
432 EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_exact);
433 
434 /**
435  * dev_pm_opp_find_level_exact() - search for an exact level
436  * @dev:		device for which we do this operation
437  * @level:		level to search for
438  *
439  * Return: Searches for exact match in the opp table and returns pointer to the
440  * matching opp if found, else returns ERR_PTR in case of error and should
441  * be handled using IS_ERR. Error return values can be:
442  * EINVAL:	for bad pointer
443  * ERANGE:	no match found for search
444  * ENODEV:	if device not found in list of registered devices
445  *
446  * The callers are required to call dev_pm_opp_put() for the returned OPP after
447  * use.
448  */
dev_pm_opp_find_level_exact(struct device * dev,unsigned int level)449 struct dev_pm_opp *dev_pm_opp_find_level_exact(struct device *dev,
450 					       unsigned int level)
451 {
452 	struct opp_table *opp_table;
453 	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
454 
455 	opp_table = _find_opp_table(dev);
456 	if (IS_ERR(opp_table)) {
457 		int r = PTR_ERR(opp_table);
458 
459 		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, r);
460 		return ERR_PTR(r);
461 	}
462 
463 	mutex_lock(&opp_table->lock);
464 
465 	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
466 		if (temp_opp->level == level) {
467 			opp = temp_opp;
468 
469 			/* Increment the reference count of OPP */
470 			dev_pm_opp_get(opp);
471 			break;
472 		}
473 	}
474 
475 	mutex_unlock(&opp_table->lock);
476 	dev_pm_opp_put_opp_table(opp_table);
477 
478 	return opp;
479 }
480 EXPORT_SYMBOL_GPL(dev_pm_opp_find_level_exact);
481 
482 /**
483  * dev_pm_opp_find_level_ceil() - search for an rounded up level
484  * @dev:		device for which we do this operation
485  * @level:		level to search for
486  *
487  * Return: Searches for rounded up match in the opp table and returns pointer
488  * to the  matching opp if found, else returns ERR_PTR in case of error and
489  * should be handled using IS_ERR. Error return values can be:
490  * EINVAL:	for bad pointer
491  * ERANGE:	no match found for search
492  * ENODEV:	if device not found in list of registered devices
493  *
494  * The callers are required to call dev_pm_opp_put() for the returned OPP after
495  * use.
496  */
dev_pm_opp_find_level_ceil(struct device * dev,unsigned int * level)497 struct dev_pm_opp *dev_pm_opp_find_level_ceil(struct device *dev,
498 					      unsigned int *level)
499 {
500 	struct opp_table *opp_table;
501 	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
502 
503 	opp_table = _find_opp_table(dev);
504 	if (IS_ERR(opp_table)) {
505 		int r = PTR_ERR(opp_table);
506 
507 		dev_err(dev, "%s: OPP table not found (%d)\n", __func__, r);
508 		return ERR_PTR(r);
509 	}
510 
511 	mutex_lock(&opp_table->lock);
512 
513 	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
514 		if (temp_opp->available && temp_opp->level >= *level) {
515 			opp = temp_opp;
516 			*level = opp->level;
517 
518 			/* Increment the reference count of OPP */
519 			dev_pm_opp_get(opp);
520 			break;
521 		}
522 	}
523 
524 	mutex_unlock(&opp_table->lock);
525 	dev_pm_opp_put_opp_table(opp_table);
526 
527 	return opp;
528 }
529 EXPORT_SYMBOL_GPL(dev_pm_opp_find_level_ceil);
530 
_find_freq_ceil(struct opp_table * opp_table,unsigned long * freq)531 static noinline struct dev_pm_opp *_find_freq_ceil(struct opp_table *opp_table,
532 						   unsigned long *freq)
533 {
534 	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
535 
536 	mutex_lock(&opp_table->lock);
537 
538 	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
539 		if (temp_opp->available && temp_opp->rate >= *freq) {
540 			opp = temp_opp;
541 			*freq = opp->rate;
542 
543 			/* Increment the reference count of OPP */
544 			dev_pm_opp_get(opp);
545 			break;
546 		}
547 	}
548 
549 	mutex_unlock(&opp_table->lock);
550 
551 	return opp;
552 }
553 
554 /**
555  * dev_pm_opp_find_freq_ceil() - Search for an rounded ceil freq
556  * @dev:	device for which we do this operation
557  * @freq:	Start frequency
558  *
559  * Search for the matching ceil *available* OPP from a starting freq
560  * for a device.
561  *
562  * Return: matching *opp and refreshes *freq accordingly, else returns
563  * ERR_PTR in case of error and should be handled using IS_ERR. Error return
564  * values can be:
565  * EINVAL:	for bad pointer
566  * ERANGE:	no match found for search
567  * ENODEV:	if device not found in list of registered devices
568  *
569  * The callers are required to call dev_pm_opp_put() for the returned OPP after
570  * use.
571  */
dev_pm_opp_find_freq_ceil(struct device * dev,unsigned long * freq)572 struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
573 					     unsigned long *freq)
574 {
575 	struct opp_table *opp_table;
576 	struct dev_pm_opp *opp;
577 
578 	if (!dev || !freq) {
579 		dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
580 		return ERR_PTR(-EINVAL);
581 	}
582 
583 	opp_table = _find_opp_table(dev);
584 	if (IS_ERR(opp_table))
585 		return ERR_CAST(opp_table);
586 
587 	opp = _find_freq_ceil(opp_table, freq);
588 
589 	dev_pm_opp_put_opp_table(opp_table);
590 
591 	return opp;
592 }
593 EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil);
594 
595 /**
596  * dev_pm_opp_find_freq_floor() - Search for a rounded floor freq
597  * @dev:	device for which we do this operation
598  * @freq:	Start frequency
599  *
600  * Search for the matching floor *available* OPP from a starting freq
601  * for a device.
602  *
603  * Return: matching *opp and refreshes *freq accordingly, else returns
604  * ERR_PTR in case of error and should be handled using IS_ERR. Error return
605  * values can be:
606  * EINVAL:	for bad pointer
607  * ERANGE:	no match found for search
608  * ENODEV:	if device not found in list of registered devices
609  *
610  * The callers are required to call dev_pm_opp_put() for the returned OPP after
611  * use.
612  */
dev_pm_opp_find_freq_floor(struct device * dev,unsigned long * freq)613 struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
614 					      unsigned long *freq)
615 {
616 	struct opp_table *opp_table;
617 	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
618 
619 	if (!dev || !freq) {
620 		dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
621 		return ERR_PTR(-EINVAL);
622 	}
623 
624 	opp_table = _find_opp_table(dev);
625 	if (IS_ERR(opp_table))
626 		return ERR_CAST(opp_table);
627 
628 	mutex_lock(&opp_table->lock);
629 
630 	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
631 		if (temp_opp->available) {
632 			/* go to the next node, before choosing prev */
633 			if (temp_opp->rate > *freq)
634 				break;
635 			else
636 				opp = temp_opp;
637 		}
638 	}
639 
640 	/* Increment the reference count of OPP */
641 	if (!IS_ERR(opp))
642 		dev_pm_opp_get(opp);
643 	mutex_unlock(&opp_table->lock);
644 	dev_pm_opp_put_opp_table(opp_table);
645 
646 	if (!IS_ERR(opp))
647 		*freq = opp->rate;
648 
649 	return opp;
650 }
651 EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor);
652 
653 /**
654  * dev_pm_opp_find_freq_ceil_by_volt() - Find OPP with highest frequency for
655  *					 target voltage.
656  * @dev:	Device for which we do this operation.
657  * @u_volt:	Target voltage.
658  *
659  * Search for OPP with highest (ceil) frequency and has voltage <= u_volt.
660  *
661  * Return: matching *opp, else returns ERR_PTR in case of error which should be
662  * handled using IS_ERR.
663  *
664  * Error return values can be:
665  * EINVAL:	bad parameters
666  *
667  * The callers are required to call dev_pm_opp_put() for the returned OPP after
668  * use.
669  */
dev_pm_opp_find_freq_ceil_by_volt(struct device * dev,unsigned long u_volt)670 struct dev_pm_opp *dev_pm_opp_find_freq_ceil_by_volt(struct device *dev,
671 						     unsigned long u_volt)
672 {
673 	struct opp_table *opp_table;
674 	struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
675 
676 	if (!dev || !u_volt) {
677 		dev_err(dev, "%s: Invalid argument volt=%lu\n", __func__,
678 			u_volt);
679 		return ERR_PTR(-EINVAL);
680 	}
681 
682 	opp_table = _find_opp_table(dev);
683 	if (IS_ERR(opp_table))
684 		return ERR_CAST(opp_table);
685 
686 	mutex_lock(&opp_table->lock);
687 
688 	list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
689 		if (temp_opp->available) {
690 			if (temp_opp->supplies[0].u_volt > u_volt)
691 				break;
692 			opp = temp_opp;
693 		}
694 	}
695 
696 	/* Increment the reference count of OPP */
697 	if (!IS_ERR(opp))
698 		dev_pm_opp_get(opp);
699 
700 	mutex_unlock(&opp_table->lock);
701 	dev_pm_opp_put_opp_table(opp_table);
702 
703 	return opp;
704 }
705 EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil_by_volt);
706 
_set_opp_voltage(struct device * dev,struct regulator * reg,struct dev_pm_opp_supply * supply)707 static int _set_opp_voltage(struct device *dev, struct regulator *reg,
708 			    struct dev_pm_opp_supply *supply)
709 {
710 	int ret;
711 
712 	/* Regulator not available for device */
713 	if (IS_ERR(reg)) {
714 		dev_dbg(dev, "%s: regulator not available: %ld\n", __func__,
715 			PTR_ERR(reg));
716 		return 0;
717 	}
718 
719 	dev_dbg(dev, "%s: voltages (mV): %lu %lu %lu\n", __func__,
720 		supply->u_volt_min, supply->u_volt, supply->u_volt_max);
721 
722 	ret = regulator_set_voltage_triplet(reg, supply->u_volt_min,
723 					    supply->u_volt, supply->u_volt_max);
724 	if (ret)
725 		dev_err(dev, "%s: failed to set voltage (%lu %lu %lu mV): %d\n",
726 			__func__, supply->u_volt_min, supply->u_volt,
727 			supply->u_volt_max, ret);
728 
729 	return ret;
730 }
731 
_generic_set_opp_clk_only(struct device * dev,struct clk * clk,unsigned long freq)732 static inline int _generic_set_opp_clk_only(struct device *dev, struct clk *clk,
733 					    unsigned long freq)
734 {
735 	int ret;
736 
737 	/* We may reach here for devices which don't change frequency */
738 	if (IS_ERR(clk))
739 		return 0;
740 
741 	ret = clk_set_rate(clk, freq);
742 	if (ret) {
743 		dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
744 			ret);
745 	}
746 
747 	return ret;
748 }
749 
_generic_set_opp_regulator(struct opp_table * opp_table,struct device * dev,struct dev_pm_opp * opp,unsigned long freq,int scaling_down)750 static int _generic_set_opp_regulator(struct opp_table *opp_table,
751 				      struct device *dev,
752 				      struct dev_pm_opp *opp,
753 				      unsigned long freq,
754 				      int scaling_down)
755 {
756 	struct regulator *reg = opp_table->regulators[0];
757 	struct dev_pm_opp *old_opp = opp_table->current_opp;
758 	int ret;
759 
760 	/* This function only supports single regulator per device */
761 	if (WARN_ON(opp_table->regulator_count > 1)) {
762 		dev_err(dev, "multiple regulators are not supported\n");
763 		return -EINVAL;
764 	}
765 
766 	/* Scaling up? Scale voltage before frequency */
767 	if (!scaling_down) {
768 		ret = _set_opp_voltage(dev, reg, opp->supplies);
769 		if (ret)
770 			goto restore_voltage;
771 	}
772 
773 	/* Change frequency */
774 	ret = _generic_set_opp_clk_only(dev, opp_table->clk, freq);
775 	if (ret)
776 		goto restore_voltage;
777 
778 	/* Scaling down? Scale voltage after frequency */
779 	if (scaling_down) {
780 		ret = _set_opp_voltage(dev, reg, opp->supplies);
781 		if (ret)
782 			goto restore_freq;
783 	}
784 
785 	/*
786 	 * Enable the regulator after setting its voltages, otherwise it breaks
787 	 * some boot-enabled regulators.
788 	 */
789 	if (unlikely(!opp_table->enabled)) {
790 		ret = regulator_enable(reg);
791 		if (ret < 0)
792 			dev_warn(dev, "Failed to enable regulator: %d", ret);
793 	}
794 
795 	return 0;
796 
797 restore_freq:
798 	if (_generic_set_opp_clk_only(dev, opp_table->clk, old_opp->rate))
799 		dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
800 			__func__, old_opp->rate);
801 restore_voltage:
802 	/* This shouldn't harm even if the voltages weren't updated earlier */
803 	_set_opp_voltage(dev, reg, old_opp->supplies);
804 
805 	return ret;
806 }
807 
_set_opp_bw(const struct opp_table * opp_table,struct dev_pm_opp * opp,struct device * dev)808 static int _set_opp_bw(const struct opp_table *opp_table,
809 		       struct dev_pm_opp *opp, struct device *dev)
810 {
811 	u32 avg, peak;
812 	int i, ret;
813 
814 	if (!opp_table->paths)
815 		return 0;
816 
817 	for (i = 0; i < opp_table->path_count; i++) {
818 		if (!opp) {
819 			avg = 0;
820 			peak = 0;
821 		} else {
822 			avg = opp->bandwidth[i].avg;
823 			peak = opp->bandwidth[i].peak;
824 		}
825 		ret = icc_set_bw(opp_table->paths[i], avg, peak);
826 		if (ret) {
827 			dev_err(dev, "Failed to %s bandwidth[%d]: %d\n",
828 				opp ? "set" : "remove", i, ret);
829 			return ret;
830 		}
831 	}
832 
833 	return 0;
834 }
835 
_set_opp_custom(const struct opp_table * opp_table,struct device * dev,struct dev_pm_opp * opp,unsigned long freq)836 static int _set_opp_custom(const struct opp_table *opp_table,
837 			   struct device *dev, struct dev_pm_opp *opp,
838 			   unsigned long freq)
839 {
840 	struct dev_pm_set_opp_data *data = opp_table->set_opp_data;
841 	struct dev_pm_opp *old_opp = opp_table->current_opp;
842 	int size;
843 
844 	/*
845 	 * We support this only if dev_pm_opp_set_regulators() was called
846 	 * earlier.
847 	 */
848 	if (opp_table->sod_supplies) {
849 		size = sizeof(*old_opp->supplies) * opp_table->regulator_count;
850 		memcpy(data->old_opp.supplies, old_opp->supplies, size);
851 		memcpy(data->new_opp.supplies, opp->supplies, size);
852 		data->regulator_count = opp_table->regulator_count;
853 	} else {
854 		data->regulator_count = 0;
855 	}
856 
857 	data->regulators = opp_table->regulators;
858 	data->clk = opp_table->clk;
859 	data->dev = dev;
860 	data->old_opp.rate = old_opp->rate;
861 	data->new_opp.rate = freq;
862 
863 	return opp_table->set_opp(data);
864 }
865 
_set_required_opp(struct device * dev,struct device * pd_dev,struct dev_pm_opp * opp,int i)866 static int _set_required_opp(struct device *dev, struct device *pd_dev,
867 			     struct dev_pm_opp *opp, int i)
868 {
869 	unsigned int pstate = likely(opp) ? opp->required_opps[i]->pstate : 0;
870 	int ret;
871 
872 	if (!pd_dev)
873 		return 0;
874 
875 	ret = dev_pm_genpd_set_performance_state(pd_dev, pstate);
876 	if (ret) {
877 		dev_err(dev, "Failed to set performance rate of %s: %d (%d)\n",
878 			dev_name(pd_dev), pstate, ret);
879 	}
880 
881 	return ret;
882 }
883 
884 /* This is only called for PM domain for now */
_set_required_opps(struct device * dev,struct opp_table * opp_table,struct dev_pm_opp * opp,bool up)885 static int _set_required_opps(struct device *dev,
886 			      struct opp_table *opp_table,
887 			      struct dev_pm_opp *opp, bool up)
888 {
889 	struct opp_table **required_opp_tables = opp_table->required_opp_tables;
890 	struct device **genpd_virt_devs = opp_table->genpd_virt_devs;
891 	int i, ret = 0;
892 
893 	if (!required_opp_tables)
894 		return 0;
895 
896 	/* required-opps not fully initialized yet */
897 	if (lazy_linking_pending(opp_table))
898 		return -EBUSY;
899 
900 	/*
901 	 * We only support genpd's OPPs in the "required-opps" for now, as we
902 	 * don't know much about other use cases. Error out if the required OPP
903 	 * doesn't belong to a genpd.
904 	 */
905 	if (unlikely(!required_opp_tables[0]->is_genpd)) {
906 		dev_err(dev, "required-opps don't belong to a genpd\n");
907 		return -ENOENT;
908 	}
909 
910 	/* Single genpd case */
911 	if (!genpd_virt_devs)
912 		return _set_required_opp(dev, dev, opp, 0);
913 
914 	/* Multiple genpd case */
915 
916 	/*
917 	 * Acquire genpd_virt_dev_lock to make sure we don't use a genpd_dev
918 	 * after it is freed from another thread.
919 	 */
920 	mutex_lock(&opp_table->genpd_virt_dev_lock);
921 
922 	/* Scaling up? Set required OPPs in normal order, else reverse */
923 	if (up) {
924 		for (i = 0; i < opp_table->required_opp_count; i++) {
925 			ret = _set_required_opp(dev, genpd_virt_devs[i], opp, i);
926 			if (ret)
927 				break;
928 		}
929 	} else {
930 		for (i = opp_table->required_opp_count - 1; i >= 0; i--) {
931 			ret = _set_required_opp(dev, genpd_virt_devs[i], opp, i);
932 			if (ret)
933 				break;
934 		}
935 	}
936 
937 	mutex_unlock(&opp_table->genpd_virt_dev_lock);
938 
939 	return ret;
940 }
941 
_find_current_opp(struct device * dev,struct opp_table * opp_table)942 static void _find_current_opp(struct device *dev, struct opp_table *opp_table)
943 {
944 	struct dev_pm_opp *opp = ERR_PTR(-ENODEV);
945 	unsigned long freq;
946 
947 	if (!IS_ERR(opp_table->clk)) {
948 		freq = clk_get_rate(opp_table->clk);
949 		opp = _find_freq_ceil(opp_table, &freq);
950 	}
951 
952 	/*
953 	 * Unable to find the current OPP ? Pick the first from the list since
954 	 * it is in ascending order, otherwise rest of the code will need to
955 	 * make special checks to validate current_opp.
956 	 */
957 	if (IS_ERR(opp)) {
958 		mutex_lock(&opp_table->lock);
959 		opp = list_first_entry(&opp_table->opp_list, struct dev_pm_opp, node);
960 		dev_pm_opp_get(opp);
961 		mutex_unlock(&opp_table->lock);
962 	}
963 
964 	opp_table->current_opp = opp;
965 }
966 
_disable_opp_table(struct device * dev,struct opp_table * opp_table)967 static int _disable_opp_table(struct device *dev, struct opp_table *opp_table)
968 {
969 	int ret;
970 
971 	if (!opp_table->enabled)
972 		return 0;
973 
974 	/*
975 	 * Some drivers need to support cases where some platforms may
976 	 * have OPP table for the device, while others don't and
977 	 * opp_set_rate() just needs to behave like clk_set_rate().
978 	 */
979 	if (!_get_opp_count(opp_table))
980 		return 0;
981 
982 	ret = _set_opp_bw(opp_table, NULL, dev);
983 	if (ret)
984 		return ret;
985 
986 	if (opp_table->regulators)
987 		regulator_disable(opp_table->regulators[0]);
988 
989 	ret = _set_required_opps(dev, opp_table, NULL, false);
990 
991 	opp_table->enabled = false;
992 	return ret;
993 }
994 
_set_opp(struct device * dev,struct opp_table * opp_table,struct dev_pm_opp * opp,unsigned long freq)995 static int _set_opp(struct device *dev, struct opp_table *opp_table,
996 		    struct dev_pm_opp *opp, unsigned long freq)
997 {
998 	struct dev_pm_opp *old_opp;
999 	int scaling_down, ret;
1000 
1001 	if (unlikely(!opp))
1002 		return _disable_opp_table(dev, opp_table);
1003 
1004 	/* Find the currently set OPP if we don't know already */
1005 	if (unlikely(!opp_table->current_opp))
1006 		_find_current_opp(dev, opp_table);
1007 
1008 	old_opp = opp_table->current_opp;
1009 
1010 	/* Return early if nothing to do */
1011 	if (old_opp == opp && opp_table->current_rate == freq &&
1012 	    opp_table->enabled) {
1013 		dev_dbg(dev, "%s: OPPs are same, nothing to do\n", __func__);
1014 		return 0;
1015 	}
1016 
1017 	dev_dbg(dev, "%s: switching OPP: Freq %lu -> %lu Hz, Level %u -> %u, Bw %u -> %u\n",
1018 		__func__, opp_table->current_rate, freq, old_opp->level,
1019 		opp->level, old_opp->bandwidth ? old_opp->bandwidth[0].peak : 0,
1020 		opp->bandwidth ? opp->bandwidth[0].peak : 0);
1021 
1022 	scaling_down = _opp_compare_key(old_opp, opp);
1023 	if (scaling_down == -1)
1024 		scaling_down = 0;
1025 
1026 	/* Scaling up? Configure required OPPs before frequency */
1027 	if (!scaling_down) {
1028 		ret = _set_required_opps(dev, opp_table, opp, true);
1029 		if (ret) {
1030 			dev_err(dev, "Failed to set required opps: %d\n", ret);
1031 			return ret;
1032 		}
1033 
1034 		ret = _set_opp_bw(opp_table, opp, dev);
1035 		if (ret) {
1036 			dev_err(dev, "Failed to set bw: %d\n", ret);
1037 			return ret;
1038 		}
1039 	}
1040 
1041 	if (opp_table->set_opp) {
1042 		ret = _set_opp_custom(opp_table, dev, opp, freq);
1043 	} else if (opp_table->regulators) {
1044 		ret = _generic_set_opp_regulator(opp_table, dev, opp, freq,
1045 						 scaling_down);
1046 	} else {
1047 		/* Only frequency scaling */
1048 		ret = _generic_set_opp_clk_only(dev, opp_table->clk, freq);
1049 	}
1050 
1051 	if (ret)
1052 		return ret;
1053 
1054 	/* Scaling down? Configure required OPPs after frequency */
1055 	if (scaling_down) {
1056 		ret = _set_opp_bw(opp_table, opp, dev);
1057 		if (ret) {
1058 			dev_err(dev, "Failed to set bw: %d\n", ret);
1059 			return ret;
1060 		}
1061 
1062 		ret = _set_required_opps(dev, opp_table, opp, false);
1063 		if (ret) {
1064 			dev_err(dev, "Failed to set required opps: %d\n", ret);
1065 			return ret;
1066 		}
1067 	}
1068 
1069 	opp_table->enabled = true;
1070 	dev_pm_opp_put(old_opp);
1071 
1072 	/* Make sure current_opp doesn't get freed */
1073 	dev_pm_opp_get(opp);
1074 	opp_table->current_opp = opp;
1075 	opp_table->current_rate = freq;
1076 
1077 	return ret;
1078 }
1079 
1080 /**
1081  * dev_pm_opp_set_rate() - Configure new OPP based on frequency
1082  * @dev:	 device for which we do this operation
1083  * @target_freq: frequency to achieve
1084  *
1085  * This configures the power-supplies to the levels specified by the OPP
1086  * corresponding to the target_freq, and programs the clock to a value <=
1087  * target_freq, as rounded by clk_round_rate(). Device wanting to run at fmax
1088  * provided by the opp, should have already rounded to the target OPP's
1089  * frequency.
1090  */
dev_pm_opp_set_rate(struct device * dev,unsigned long target_freq)1091 int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
1092 {
1093 	struct opp_table *opp_table;
1094 	unsigned long freq = 0, temp_freq;
1095 	struct dev_pm_opp *opp = NULL;
1096 	int ret;
1097 
1098 	opp_table = _find_opp_table(dev);
1099 	if (IS_ERR(opp_table)) {
1100 		dev_err(dev, "%s: device's opp table doesn't exist\n", __func__);
1101 		return PTR_ERR(opp_table);
1102 	}
1103 
1104 	if (target_freq) {
1105 		/*
1106 		 * For IO devices which require an OPP on some platforms/SoCs
1107 		 * while just needing to scale the clock on some others
1108 		 * we look for empty OPP tables with just a clock handle and
1109 		 * scale only the clk. This makes dev_pm_opp_set_rate()
1110 		 * equivalent to a clk_set_rate()
1111 		 */
1112 		if (!_get_opp_count(opp_table)) {
1113 			ret = _generic_set_opp_clk_only(dev, opp_table->clk, target_freq);
1114 			goto put_opp_table;
1115 		}
1116 
1117 		freq = clk_round_rate(opp_table->clk, target_freq);
1118 		if ((long)freq <= 0)
1119 			freq = target_freq;
1120 
1121 		/*
1122 		 * The clock driver may support finer resolution of the
1123 		 * frequencies than the OPP table, don't update the frequency we
1124 		 * pass to clk_set_rate() here.
1125 		 */
1126 		temp_freq = freq;
1127 		opp = _find_freq_ceil(opp_table, &temp_freq);
1128 		if (IS_ERR(opp)) {
1129 			ret = PTR_ERR(opp);
1130 			dev_err(dev, "%s: failed to find OPP for freq %lu (%d)\n",
1131 				__func__, freq, ret);
1132 			goto put_opp_table;
1133 		}
1134 	}
1135 
1136 	ret = _set_opp(dev, opp_table, opp, freq);
1137 
1138 	if (target_freq)
1139 		dev_pm_opp_put(opp);
1140 put_opp_table:
1141 	dev_pm_opp_put_opp_table(opp_table);
1142 	return ret;
1143 }
1144 EXPORT_SYMBOL_GPL(dev_pm_opp_set_rate);
1145 
1146 /**
1147  * dev_pm_opp_set_opp() - Configure device for OPP
1148  * @dev: device for which we do this operation
1149  * @opp: OPP to set to
1150  *
1151  * This configures the device based on the properties of the OPP passed to this
1152  * routine.
1153  *
1154  * Return: 0 on success, a negative error number otherwise.
1155  */
dev_pm_opp_set_opp(struct device * dev,struct dev_pm_opp * opp)1156 int dev_pm_opp_set_opp(struct device *dev, struct dev_pm_opp *opp)
1157 {
1158 	struct opp_table *opp_table;
1159 	int ret;
1160 
1161 	opp_table = _find_opp_table(dev);
1162 	if (IS_ERR(opp_table)) {
1163 		dev_err(dev, "%s: device opp doesn't exist\n", __func__);
1164 		return PTR_ERR(opp_table);
1165 	}
1166 
1167 	ret = _set_opp(dev, opp_table, opp, opp ? opp->rate : 0);
1168 	dev_pm_opp_put_opp_table(opp_table);
1169 
1170 	return ret;
1171 }
1172 EXPORT_SYMBOL_GPL(dev_pm_opp_set_opp);
1173 
1174 /* OPP-dev Helpers */
_remove_opp_dev(struct opp_device * opp_dev,struct opp_table * opp_table)1175 static void _remove_opp_dev(struct opp_device *opp_dev,
1176 			    struct opp_table *opp_table)
1177 {
1178 	opp_debug_unregister(opp_dev, opp_table);
1179 	list_del(&opp_dev->node);
1180 	kfree(opp_dev);
1181 }
1182 
_add_opp_dev(const struct device * dev,struct opp_table * opp_table)1183 struct opp_device *_add_opp_dev(const struct device *dev,
1184 				struct opp_table *opp_table)
1185 {
1186 	struct opp_device *opp_dev;
1187 
1188 	opp_dev = kzalloc(sizeof(*opp_dev), GFP_KERNEL);
1189 	if (!opp_dev)
1190 		return NULL;
1191 
1192 	/* Initialize opp-dev */
1193 	opp_dev->dev = dev;
1194 
1195 	mutex_lock(&opp_table->lock);
1196 	list_add(&opp_dev->node, &opp_table->dev_list);
1197 	mutex_unlock(&opp_table->lock);
1198 
1199 	/* Create debugfs entries for the opp_table */
1200 	opp_debug_register(opp_dev, opp_table);
1201 
1202 	return opp_dev;
1203 }
1204 
_allocate_opp_table(struct device * dev,int index)1205 static struct opp_table *_allocate_opp_table(struct device *dev, int index)
1206 {
1207 	struct opp_table *opp_table;
1208 	struct opp_device *opp_dev;
1209 	int ret;
1210 
1211 	/*
1212 	 * Allocate a new OPP table. In the infrequent case where a new
1213 	 * device is needed to be added, we pay this penalty.
1214 	 */
1215 	opp_table = kzalloc(sizeof(*opp_table), GFP_KERNEL);
1216 	if (!opp_table)
1217 		return ERR_PTR(-ENOMEM);
1218 
1219 	mutex_init(&opp_table->lock);
1220 	mutex_init(&opp_table->genpd_virt_dev_lock);
1221 	INIT_LIST_HEAD(&opp_table->dev_list);
1222 	INIT_LIST_HEAD(&opp_table->lazy);
1223 
1224 	/* Mark regulator count uninitialized */
1225 	opp_table->regulator_count = -1;
1226 
1227 	opp_dev = _add_opp_dev(dev, opp_table);
1228 	if (!opp_dev) {
1229 		ret = -ENOMEM;
1230 		goto err;
1231 	}
1232 
1233 	_of_init_opp_table(opp_table, dev, index);
1234 
1235 	/* Find interconnect path(s) for the device */
1236 	ret = dev_pm_opp_of_find_icc_paths(dev, opp_table);
1237 	if (ret) {
1238 		if (ret == -EPROBE_DEFER)
1239 			goto remove_opp_dev;
1240 
1241 		dev_warn(dev, "%s: Error finding interconnect paths: %d\n",
1242 			 __func__, ret);
1243 	}
1244 
1245 	BLOCKING_INIT_NOTIFIER_HEAD(&opp_table->head);
1246 	INIT_LIST_HEAD(&opp_table->opp_list);
1247 	kref_init(&opp_table->kref);
1248 
1249 	return opp_table;
1250 
1251 remove_opp_dev:
1252 	_of_clear_opp_table(opp_table);
1253 	_remove_opp_dev(opp_dev, opp_table);
1254 	mutex_destroy(&opp_table->genpd_virt_dev_lock);
1255 	mutex_destroy(&opp_table->lock);
1256 err:
1257 	kfree(opp_table);
1258 	return ERR_PTR(ret);
1259 }
1260 
_get_opp_table_kref(struct opp_table * opp_table)1261 void _get_opp_table_kref(struct opp_table *opp_table)
1262 {
1263 	kref_get(&opp_table->kref);
1264 }
1265 
_update_opp_table_clk(struct device * dev,struct opp_table * opp_table,bool getclk)1266 static struct opp_table *_update_opp_table_clk(struct device *dev,
1267 					       struct opp_table *opp_table,
1268 					       bool getclk)
1269 {
1270 	int ret;
1271 
1272 	/*
1273 	 * Return early if we don't need to get clk or we have already tried it
1274 	 * earlier.
1275 	 */
1276 	if (!getclk || IS_ERR(opp_table) || opp_table->clk)
1277 		return opp_table;
1278 
1279 	/* Find clk for the device */
1280 	opp_table->clk = clk_get(dev, NULL);
1281 
1282 	ret = PTR_ERR_OR_ZERO(opp_table->clk);
1283 	if (!ret)
1284 		return opp_table;
1285 
1286 	if (ret == -ENOENT) {
1287 		dev_dbg(dev, "%s: Couldn't find clock: %d\n", __func__, ret);
1288 		return opp_table;
1289 	}
1290 
1291 	dev_pm_opp_put_opp_table(opp_table);
1292 	dev_err_probe(dev, ret, "Couldn't find clock\n");
1293 
1294 	return ERR_PTR(ret);
1295 }
1296 
1297 /*
1298  * We need to make sure that the OPP table for a device doesn't get added twice,
1299  * if this routine gets called in parallel with the same device pointer.
1300  *
1301  * The simplest way to enforce that is to perform everything (find existing
1302  * table and if not found, create a new one) under the opp_table_lock, so only
1303  * one creator gets access to the same. But that expands the critical section
1304  * under the lock and may end up causing circular dependencies with frameworks
1305  * like debugfs, interconnect or clock framework as they may be direct or
1306  * indirect users of OPP core.
1307  *
1308  * And for that reason we have to go for a bit tricky implementation here, which
1309  * uses the opp_tables_busy flag to indicate if another creator is in the middle
1310  * of adding an OPP table and others should wait for it to finish.
1311  */
_add_opp_table_indexed(struct device * dev,int index,bool getclk)1312 struct opp_table *_add_opp_table_indexed(struct device *dev, int index,
1313 					 bool getclk)
1314 {
1315 	struct opp_table *opp_table;
1316 
1317 again:
1318 	mutex_lock(&opp_table_lock);
1319 
1320 	opp_table = _find_opp_table_unlocked(dev);
1321 	if (!IS_ERR(opp_table))
1322 		goto unlock;
1323 
1324 	/*
1325 	 * The opp_tables list or an OPP table's dev_list is getting updated by
1326 	 * another user, wait for it to finish.
1327 	 */
1328 	if (unlikely(opp_tables_busy)) {
1329 		mutex_unlock(&opp_table_lock);
1330 		cpu_relax();
1331 		goto again;
1332 	}
1333 
1334 	opp_tables_busy = true;
1335 	opp_table = _managed_opp(dev, index);
1336 
1337 	/* Drop the lock to reduce the size of critical section */
1338 	mutex_unlock(&opp_table_lock);
1339 
1340 	if (opp_table) {
1341 		if (!_add_opp_dev(dev, opp_table)) {
1342 			dev_pm_opp_put_opp_table(opp_table);
1343 			opp_table = ERR_PTR(-ENOMEM);
1344 		}
1345 
1346 		mutex_lock(&opp_table_lock);
1347 	} else {
1348 		opp_table = _allocate_opp_table(dev, index);
1349 
1350 		mutex_lock(&opp_table_lock);
1351 		if (!IS_ERR(opp_table))
1352 			list_add(&opp_table->node, &opp_tables);
1353 	}
1354 
1355 	opp_tables_busy = false;
1356 
1357 unlock:
1358 	mutex_unlock(&opp_table_lock);
1359 
1360 	return _update_opp_table_clk(dev, opp_table, getclk);
1361 }
1362 
_add_opp_table(struct device * dev,bool getclk)1363 static struct opp_table *_add_opp_table(struct device *dev, bool getclk)
1364 {
1365 	return _add_opp_table_indexed(dev, 0, getclk);
1366 }
1367 
dev_pm_opp_get_opp_table(struct device * dev)1368 struct opp_table *dev_pm_opp_get_opp_table(struct device *dev)
1369 {
1370 	return _find_opp_table(dev);
1371 }
1372 EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_table);
1373 
_opp_table_kref_release(struct kref * kref)1374 static void _opp_table_kref_release(struct kref *kref)
1375 {
1376 	struct opp_table *opp_table = container_of(kref, struct opp_table, kref);
1377 	struct opp_device *opp_dev, *temp;
1378 	int i;
1379 
1380 	/* Drop the lock as soon as we can */
1381 	list_del(&opp_table->node);
1382 	mutex_unlock(&opp_table_lock);
1383 
1384 	if (opp_table->current_opp)
1385 		dev_pm_opp_put(opp_table->current_opp);
1386 
1387 	_of_clear_opp_table(opp_table);
1388 
1389 	/* Release clk */
1390 	if (!IS_ERR(opp_table->clk))
1391 		clk_put(opp_table->clk);
1392 
1393 	if (opp_table->paths) {
1394 		for (i = 0; i < opp_table->path_count; i++)
1395 			icc_put(opp_table->paths[i]);
1396 		kfree(opp_table->paths);
1397 	}
1398 
1399 	WARN_ON(!list_empty(&opp_table->opp_list));
1400 
1401 	list_for_each_entry_safe(opp_dev, temp, &opp_table->dev_list, node) {
1402 		/*
1403 		 * The OPP table is getting removed, drop the performance state
1404 		 * constraints.
1405 		 */
1406 		if (opp_table->genpd_performance_state)
1407 			dev_pm_genpd_set_performance_state((struct device *)(opp_dev->dev), 0);
1408 
1409 		_remove_opp_dev(opp_dev, opp_table);
1410 	}
1411 
1412 	mutex_destroy(&opp_table->genpd_virt_dev_lock);
1413 	mutex_destroy(&opp_table->lock);
1414 	kfree(opp_table);
1415 }
1416 
dev_pm_opp_put_opp_table(struct opp_table * opp_table)1417 void dev_pm_opp_put_opp_table(struct opp_table *opp_table)
1418 {
1419 	kref_put_mutex(&opp_table->kref, _opp_table_kref_release,
1420 		       &opp_table_lock);
1421 }
1422 EXPORT_SYMBOL_GPL(dev_pm_opp_put_opp_table);
1423 
_opp_free(struct dev_pm_opp * opp)1424 void _opp_free(struct dev_pm_opp *opp)
1425 {
1426 	kfree(opp);
1427 }
1428 
_opp_kref_release(struct kref * kref)1429 static void _opp_kref_release(struct kref *kref)
1430 {
1431 	struct dev_pm_opp *opp = container_of(kref, struct dev_pm_opp, kref);
1432 	struct opp_table *opp_table = opp->opp_table;
1433 
1434 	list_del(&opp->node);
1435 	mutex_unlock(&opp_table->lock);
1436 
1437 	/*
1438 	 * Notify the changes in the availability of the operable
1439 	 * frequency/voltage list.
1440 	 */
1441 	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_REMOVE, opp);
1442 	_of_opp_free_required_opps(opp_table, opp);
1443 	opp_debug_remove_one(opp);
1444 	kfree(opp);
1445 }
1446 
dev_pm_opp_get(struct dev_pm_opp * opp)1447 void dev_pm_opp_get(struct dev_pm_opp *opp)
1448 {
1449 	kref_get(&opp->kref);
1450 }
1451 
dev_pm_opp_put(struct dev_pm_opp * opp)1452 void dev_pm_opp_put(struct dev_pm_opp *opp)
1453 {
1454 	kref_put_mutex(&opp->kref, _opp_kref_release, &opp->opp_table->lock);
1455 }
1456 EXPORT_SYMBOL_GPL(dev_pm_opp_put);
1457 
1458 /**
1459  * dev_pm_opp_remove()  - Remove an OPP from OPP table
1460  * @dev:	device for which we do this operation
1461  * @freq:	OPP to remove with matching 'freq'
1462  *
1463  * This function removes an opp from the opp table.
1464  */
dev_pm_opp_remove(struct device * dev,unsigned long freq)1465 void dev_pm_opp_remove(struct device *dev, unsigned long freq)
1466 {
1467 	struct dev_pm_opp *opp;
1468 	struct opp_table *opp_table;
1469 	bool found = false;
1470 
1471 	opp_table = _find_opp_table(dev);
1472 	if (IS_ERR(opp_table))
1473 		return;
1474 
1475 	mutex_lock(&opp_table->lock);
1476 
1477 	list_for_each_entry(opp, &opp_table->opp_list, node) {
1478 		if (opp->rate == freq) {
1479 			found = true;
1480 			break;
1481 		}
1482 	}
1483 
1484 	mutex_unlock(&opp_table->lock);
1485 
1486 	if (found) {
1487 		dev_pm_opp_put(opp);
1488 
1489 		/* Drop the reference taken by dev_pm_opp_add() */
1490 		dev_pm_opp_put_opp_table(opp_table);
1491 	} else {
1492 		dev_warn(dev, "%s: Couldn't find OPP with freq: %lu\n",
1493 			 __func__, freq);
1494 	}
1495 
1496 	/* Drop the reference taken by _find_opp_table() */
1497 	dev_pm_opp_put_opp_table(opp_table);
1498 }
1499 EXPORT_SYMBOL_GPL(dev_pm_opp_remove);
1500 
_opp_get_next(struct opp_table * opp_table,bool dynamic)1501 static struct dev_pm_opp *_opp_get_next(struct opp_table *opp_table,
1502 					bool dynamic)
1503 {
1504 	struct dev_pm_opp *opp = NULL, *temp;
1505 
1506 	mutex_lock(&opp_table->lock);
1507 	list_for_each_entry(temp, &opp_table->opp_list, node) {
1508 		/*
1509 		 * Refcount must be dropped only once for each OPP by OPP core,
1510 		 * do that with help of "removed" flag.
1511 		 */
1512 		if (!temp->removed && dynamic == temp->dynamic) {
1513 			opp = temp;
1514 			break;
1515 		}
1516 	}
1517 
1518 	mutex_unlock(&opp_table->lock);
1519 	return opp;
1520 }
1521 
1522 /*
1523  * Can't call dev_pm_opp_put() from under the lock as debugfs removal needs to
1524  * happen lock less to avoid circular dependency issues. This routine must be
1525  * called without the opp_table->lock held.
1526  */
_opp_remove_all(struct opp_table * opp_table,bool dynamic)1527 static void _opp_remove_all(struct opp_table *opp_table, bool dynamic)
1528 {
1529 	struct dev_pm_opp *opp;
1530 
1531 	while ((opp = _opp_get_next(opp_table, dynamic))) {
1532 		opp->removed = true;
1533 		dev_pm_opp_put(opp);
1534 
1535 		/* Drop the references taken by dev_pm_opp_add() */
1536 		if (dynamic)
1537 			dev_pm_opp_put_opp_table(opp_table);
1538 	}
1539 }
1540 
_opp_remove_all_static(struct opp_table * opp_table)1541 bool _opp_remove_all_static(struct opp_table *opp_table)
1542 {
1543 	mutex_lock(&opp_table->lock);
1544 
1545 	if (!opp_table->parsed_static_opps) {
1546 		mutex_unlock(&opp_table->lock);
1547 		return false;
1548 	}
1549 
1550 	if (--opp_table->parsed_static_opps) {
1551 		mutex_unlock(&opp_table->lock);
1552 		return true;
1553 	}
1554 
1555 	mutex_unlock(&opp_table->lock);
1556 
1557 	_opp_remove_all(opp_table, false);
1558 	return true;
1559 }
1560 
1561 /**
1562  * dev_pm_opp_remove_all_dynamic() - Remove all dynamically created OPPs
1563  * @dev:	device for which we do this operation
1564  *
1565  * This function removes all dynamically created OPPs from the opp table.
1566  */
dev_pm_opp_remove_all_dynamic(struct device * dev)1567 void dev_pm_opp_remove_all_dynamic(struct device *dev)
1568 {
1569 	struct opp_table *opp_table;
1570 
1571 	opp_table = _find_opp_table(dev);
1572 	if (IS_ERR(opp_table))
1573 		return;
1574 
1575 	_opp_remove_all(opp_table, true);
1576 
1577 	/* Drop the reference taken by _find_opp_table() */
1578 	dev_pm_opp_put_opp_table(opp_table);
1579 }
1580 EXPORT_SYMBOL_GPL(dev_pm_opp_remove_all_dynamic);
1581 
_opp_allocate(struct opp_table * table)1582 struct dev_pm_opp *_opp_allocate(struct opp_table *table)
1583 {
1584 	struct dev_pm_opp *opp;
1585 	int supply_count, supply_size, icc_size;
1586 
1587 	/* Allocate space for at least one supply */
1588 	supply_count = table->regulator_count > 0 ? table->regulator_count : 1;
1589 	supply_size = sizeof(*opp->supplies) * supply_count;
1590 	icc_size = sizeof(*opp->bandwidth) * table->path_count;
1591 
1592 	/* allocate new OPP node and supplies structures */
1593 	opp = kzalloc(sizeof(*opp) + supply_size + icc_size, GFP_KERNEL);
1594 
1595 	if (!opp)
1596 		return NULL;
1597 
1598 	/* Put the supplies at the end of the OPP structure as an empty array */
1599 	opp->supplies = (struct dev_pm_opp_supply *)(opp + 1);
1600 	if (icc_size)
1601 		opp->bandwidth = (struct dev_pm_opp_icc_bw *)(opp->supplies + supply_count);
1602 	INIT_LIST_HEAD(&opp->node);
1603 
1604 	return opp;
1605 }
1606 
_opp_supported_by_regulators(struct dev_pm_opp * opp,struct opp_table * opp_table)1607 static bool _opp_supported_by_regulators(struct dev_pm_opp *opp,
1608 					 struct opp_table *opp_table)
1609 {
1610 	struct regulator *reg;
1611 	int i;
1612 
1613 	if (!opp_table->regulators)
1614 		return true;
1615 
1616 	for (i = 0; i < opp_table->regulator_count; i++) {
1617 		reg = opp_table->regulators[i];
1618 
1619 		if (!regulator_is_supported_voltage(reg,
1620 					opp->supplies[i].u_volt_min,
1621 					opp->supplies[i].u_volt_max)) {
1622 			pr_warn("%s: OPP minuV: %lu maxuV: %lu, not supported by regulator\n",
1623 				__func__, opp->supplies[i].u_volt_min,
1624 				opp->supplies[i].u_volt_max);
1625 			return false;
1626 		}
1627 	}
1628 
1629 	return true;
1630 }
1631 
_opp_compare_key(struct dev_pm_opp * opp1,struct dev_pm_opp * opp2)1632 int _opp_compare_key(struct dev_pm_opp *opp1, struct dev_pm_opp *opp2)
1633 {
1634 	if (opp1->rate != opp2->rate)
1635 		return opp1->rate < opp2->rate ? -1 : 1;
1636 	if (opp1->bandwidth && opp2->bandwidth &&
1637 	    opp1->bandwidth[0].peak != opp2->bandwidth[0].peak)
1638 		return opp1->bandwidth[0].peak < opp2->bandwidth[0].peak ? -1 : 1;
1639 	if (opp1->level != opp2->level)
1640 		return opp1->level < opp2->level ? -1 : 1;
1641 	return 0;
1642 }
1643 
_opp_is_duplicate(struct device * dev,struct dev_pm_opp * new_opp,struct opp_table * opp_table,struct list_head ** head)1644 static int _opp_is_duplicate(struct device *dev, struct dev_pm_opp *new_opp,
1645 			     struct opp_table *opp_table,
1646 			     struct list_head **head)
1647 {
1648 	struct dev_pm_opp *opp;
1649 	int opp_cmp;
1650 
1651 	/*
1652 	 * Insert new OPP in order of increasing frequency and discard if
1653 	 * already present.
1654 	 *
1655 	 * Need to use &opp_table->opp_list in the condition part of the 'for'
1656 	 * loop, don't replace it with head otherwise it will become an infinite
1657 	 * loop.
1658 	 */
1659 	list_for_each_entry(opp, &opp_table->opp_list, node) {
1660 		opp_cmp = _opp_compare_key(new_opp, opp);
1661 		if (opp_cmp > 0) {
1662 			*head = &opp->node;
1663 			continue;
1664 		}
1665 
1666 		if (opp_cmp < 0)
1667 			return 0;
1668 
1669 		/* Duplicate OPPs */
1670 		dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n",
1671 			 __func__, opp->rate, opp->supplies[0].u_volt,
1672 			 opp->available, new_opp->rate,
1673 			 new_opp->supplies[0].u_volt, new_opp->available);
1674 
1675 		/* Should we compare voltages for all regulators here ? */
1676 		return opp->available &&
1677 		       new_opp->supplies[0].u_volt == opp->supplies[0].u_volt ? -EBUSY : -EEXIST;
1678 	}
1679 
1680 	return 0;
1681 }
1682 
_required_opps_available(struct dev_pm_opp * opp,int count)1683 void _required_opps_available(struct dev_pm_opp *opp, int count)
1684 {
1685 	int i;
1686 
1687 	for (i = 0; i < count; i++) {
1688 		if (opp->required_opps[i]->available)
1689 			continue;
1690 
1691 		opp->available = false;
1692 		pr_warn("%s: OPP not supported by required OPP %pOF (%lu)\n",
1693 			 __func__, opp->required_opps[i]->np, opp->rate);
1694 		return;
1695 	}
1696 }
1697 
1698 /*
1699  * Returns:
1700  * 0: On success. And appropriate error message for duplicate OPPs.
1701  * -EBUSY: For OPP with same freq/volt and is available. The callers of
1702  *  _opp_add() must return 0 if they receive -EBUSY from it. This is to make
1703  *  sure we don't print error messages unnecessarily if different parts of
1704  *  kernel try to initialize the OPP table.
1705  * -EEXIST: For OPP with same freq but different volt or is unavailable. This
1706  *  should be considered an error by the callers of _opp_add().
1707  */
_opp_add(struct device * dev,struct dev_pm_opp * new_opp,struct opp_table * opp_table,bool rate_not_available)1708 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp,
1709 	     struct opp_table *opp_table, bool rate_not_available)
1710 {
1711 	struct list_head *head;
1712 	int ret;
1713 
1714 	mutex_lock(&opp_table->lock);
1715 	head = &opp_table->opp_list;
1716 
1717 	ret = _opp_is_duplicate(dev, new_opp, opp_table, &head);
1718 	if (ret) {
1719 		mutex_unlock(&opp_table->lock);
1720 		return ret;
1721 	}
1722 
1723 	list_add(&new_opp->node, head);
1724 	mutex_unlock(&opp_table->lock);
1725 
1726 	new_opp->opp_table = opp_table;
1727 	kref_init(&new_opp->kref);
1728 
1729 	opp_debug_create_one(new_opp, opp_table);
1730 
1731 	if (!_opp_supported_by_regulators(new_opp, opp_table)) {
1732 		new_opp->available = false;
1733 		dev_warn(dev, "%s: OPP not supported by regulators (%lu)\n",
1734 			 __func__, new_opp->rate);
1735 	}
1736 
1737 	/* required-opps not fully initialized yet */
1738 	if (lazy_linking_pending(opp_table))
1739 		return 0;
1740 
1741 	_required_opps_available(new_opp, opp_table->required_opp_count);
1742 
1743 	return 0;
1744 }
1745 
1746 /**
1747  * _opp_add_v1() - Allocate a OPP based on v1 bindings.
1748  * @opp_table:	OPP table
1749  * @dev:	device for which we do this operation
1750  * @freq:	Frequency in Hz for this OPP
1751  * @u_volt:	Voltage in uVolts for this OPP
1752  * @dynamic:	Dynamically added OPPs.
1753  *
1754  * This function adds an opp definition to the opp table and returns status.
1755  * The opp is made available by default and it can be controlled using
1756  * dev_pm_opp_enable/disable functions and may be removed by dev_pm_opp_remove.
1757  *
1758  * NOTE: "dynamic" parameter impacts OPPs added by the dev_pm_opp_of_add_table
1759  * and freed by dev_pm_opp_of_remove_table.
1760  *
1761  * Return:
1762  * 0		On success OR
1763  *		Duplicate OPPs (both freq and volt are same) and opp->available
1764  * -EEXIST	Freq are same and volt are different OR
1765  *		Duplicate OPPs (both freq and volt are same) and !opp->available
1766  * -ENOMEM	Memory allocation failure
1767  */
_opp_add_v1(struct opp_table * opp_table,struct device * dev,unsigned long freq,long u_volt,bool dynamic)1768 int _opp_add_v1(struct opp_table *opp_table, struct device *dev,
1769 		unsigned long freq, long u_volt, bool dynamic)
1770 {
1771 	struct dev_pm_opp *new_opp;
1772 	unsigned long tol;
1773 	int ret;
1774 
1775 	new_opp = _opp_allocate(opp_table);
1776 	if (!new_opp)
1777 		return -ENOMEM;
1778 
1779 	/* populate the opp table */
1780 	new_opp->rate = freq;
1781 	tol = u_volt * opp_table->voltage_tolerance_v1 / 100;
1782 	new_opp->supplies[0].u_volt = u_volt;
1783 	new_opp->supplies[0].u_volt_min = u_volt - tol;
1784 	new_opp->supplies[0].u_volt_max = u_volt + tol;
1785 	new_opp->available = true;
1786 	new_opp->dynamic = dynamic;
1787 
1788 	ret = _opp_add(dev, new_opp, opp_table, false);
1789 	if (ret) {
1790 		/* Don't return error for duplicate OPPs */
1791 		if (ret == -EBUSY)
1792 			ret = 0;
1793 		goto free_opp;
1794 	}
1795 
1796 	/*
1797 	 * Notify the changes in the availability of the operable
1798 	 * frequency/voltage list.
1799 	 */
1800 	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
1801 	return 0;
1802 
1803 free_opp:
1804 	_opp_free(new_opp);
1805 
1806 	return ret;
1807 }
1808 
1809 /**
1810  * dev_pm_opp_set_supported_hw() - Set supported platforms
1811  * @dev: Device for which supported-hw has to be set.
1812  * @versions: Array of hierarchy of versions to match.
1813  * @count: Number of elements in the array.
1814  *
1815  * This is required only for the V2 bindings, and it enables a platform to
1816  * specify the hierarchy of versions it supports. OPP layer will then enable
1817  * OPPs, which are available for those versions, based on its 'opp-supported-hw'
1818  * property.
1819  */
dev_pm_opp_set_supported_hw(struct device * dev,const u32 * versions,unsigned int count)1820 struct opp_table *dev_pm_opp_set_supported_hw(struct device *dev,
1821 			const u32 *versions, unsigned int count)
1822 {
1823 	struct opp_table *opp_table;
1824 
1825 	opp_table = _add_opp_table(dev, false);
1826 	if (IS_ERR(opp_table))
1827 		return opp_table;
1828 
1829 	/* Make sure there are no concurrent readers while updating opp_table */
1830 	WARN_ON(!list_empty(&opp_table->opp_list));
1831 
1832 	/* Another CPU that shares the OPP table has set the property ? */
1833 	if (opp_table->supported_hw)
1834 		return opp_table;
1835 
1836 	opp_table->supported_hw = kmemdup(versions, count * sizeof(*versions),
1837 					GFP_KERNEL);
1838 	if (!opp_table->supported_hw) {
1839 		dev_pm_opp_put_opp_table(opp_table);
1840 		return ERR_PTR(-ENOMEM);
1841 	}
1842 
1843 	opp_table->supported_hw_count = count;
1844 
1845 	return opp_table;
1846 }
1847 EXPORT_SYMBOL_GPL(dev_pm_opp_set_supported_hw);
1848 
1849 /**
1850  * dev_pm_opp_put_supported_hw() - Releases resources blocked for supported hw
1851  * @opp_table: OPP table returned by dev_pm_opp_set_supported_hw().
1852  *
1853  * This is required only for the V2 bindings, and is called for a matching
1854  * dev_pm_opp_set_supported_hw(). Until this is called, the opp_table structure
1855  * will not be freed.
1856  */
dev_pm_opp_put_supported_hw(struct opp_table * opp_table)1857 void dev_pm_opp_put_supported_hw(struct opp_table *opp_table)
1858 {
1859 	if (unlikely(!opp_table))
1860 		return;
1861 
1862 	kfree(opp_table->supported_hw);
1863 	opp_table->supported_hw = NULL;
1864 	opp_table->supported_hw_count = 0;
1865 
1866 	dev_pm_opp_put_opp_table(opp_table);
1867 }
1868 EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw);
1869 
devm_pm_opp_supported_hw_release(void * data)1870 static void devm_pm_opp_supported_hw_release(void *data)
1871 {
1872 	dev_pm_opp_put_supported_hw(data);
1873 }
1874 
1875 /**
1876  * devm_pm_opp_set_supported_hw() - Set supported platforms
1877  * @dev: Device for which supported-hw has to be set.
1878  * @versions: Array of hierarchy of versions to match.
1879  * @count: Number of elements in the array.
1880  *
1881  * This is a resource-managed variant of dev_pm_opp_set_supported_hw().
1882  *
1883  * Return: 0 on success and errorno otherwise.
1884  */
devm_pm_opp_set_supported_hw(struct device * dev,const u32 * versions,unsigned int count)1885 int devm_pm_opp_set_supported_hw(struct device *dev, const u32 *versions,
1886 				 unsigned int count)
1887 {
1888 	struct opp_table *opp_table;
1889 
1890 	opp_table = dev_pm_opp_set_supported_hw(dev, versions, count);
1891 	if (IS_ERR(opp_table))
1892 		return PTR_ERR(opp_table);
1893 
1894 	return devm_add_action_or_reset(dev, devm_pm_opp_supported_hw_release,
1895 					opp_table);
1896 }
1897 EXPORT_SYMBOL_GPL(devm_pm_opp_set_supported_hw);
1898 
1899 /**
1900  * dev_pm_opp_set_prop_name() - Set prop-extn name
1901  * @dev: Device for which the prop-name has to be set.
1902  * @name: name to postfix to properties.
1903  *
1904  * This is required only for the V2 bindings, and it enables a platform to
1905  * specify the extn to be used for certain property names. The properties to
1906  * which the extension will apply are opp-microvolt and opp-microamp. OPP core
1907  * should postfix the property name with -<name> while looking for them.
1908  */
dev_pm_opp_set_prop_name(struct device * dev,const char * name)1909 struct opp_table *dev_pm_opp_set_prop_name(struct device *dev, const char *name)
1910 {
1911 	struct opp_table *opp_table;
1912 
1913 	opp_table = _add_opp_table(dev, false);
1914 	if (IS_ERR(opp_table))
1915 		return opp_table;
1916 
1917 	/* Make sure there are no concurrent readers while updating opp_table */
1918 	WARN_ON(!list_empty(&opp_table->opp_list));
1919 
1920 	/* Another CPU that shares the OPP table has set the property ? */
1921 	if (opp_table->prop_name)
1922 		return opp_table;
1923 
1924 	opp_table->prop_name = kstrdup(name, GFP_KERNEL);
1925 	if (!opp_table->prop_name) {
1926 		dev_pm_opp_put_opp_table(opp_table);
1927 		return ERR_PTR(-ENOMEM);
1928 	}
1929 
1930 	return opp_table;
1931 }
1932 EXPORT_SYMBOL_GPL(dev_pm_opp_set_prop_name);
1933 
1934 /**
1935  * dev_pm_opp_put_prop_name() - Releases resources blocked for prop-name
1936  * @opp_table: OPP table returned by dev_pm_opp_set_prop_name().
1937  *
1938  * This is required only for the V2 bindings, and is called for a matching
1939  * dev_pm_opp_set_prop_name(). Until this is called, the opp_table structure
1940  * will not be freed.
1941  */
dev_pm_opp_put_prop_name(struct opp_table * opp_table)1942 void dev_pm_opp_put_prop_name(struct opp_table *opp_table)
1943 {
1944 	if (unlikely(!opp_table))
1945 		return;
1946 
1947 	kfree(opp_table->prop_name);
1948 	opp_table->prop_name = NULL;
1949 
1950 	dev_pm_opp_put_opp_table(opp_table);
1951 }
1952 EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name);
1953 
1954 /**
1955  * dev_pm_opp_set_regulators() - Set regulator names for the device
1956  * @dev: Device for which regulator name is being set.
1957  * @names: Array of pointers to the names of the regulator.
1958  * @count: Number of regulators.
1959  *
1960  * In order to support OPP switching, OPP layer needs to know the name of the
1961  * device's regulators, as the core would be required to switch voltages as
1962  * well.
1963  *
1964  * This must be called before any OPPs are initialized for the device.
1965  */
dev_pm_opp_set_regulators(struct device * dev,const char * const names[],unsigned int count)1966 struct opp_table *dev_pm_opp_set_regulators(struct device *dev,
1967 					    const char * const names[],
1968 					    unsigned int count)
1969 {
1970 	struct dev_pm_opp_supply *supplies;
1971 	struct opp_table *opp_table;
1972 	struct regulator *reg;
1973 	int ret, i;
1974 
1975 	opp_table = _add_opp_table(dev, false);
1976 	if (IS_ERR(opp_table))
1977 		return opp_table;
1978 
1979 	/* This should be called before OPPs are initialized */
1980 	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
1981 		ret = -EBUSY;
1982 		goto err;
1983 	}
1984 
1985 	/* Another CPU that shares the OPP table has set the regulators ? */
1986 	if (opp_table->regulators)
1987 		return opp_table;
1988 
1989 	opp_table->regulators = kmalloc_array(count,
1990 					      sizeof(*opp_table->regulators),
1991 					      GFP_KERNEL);
1992 	if (!opp_table->regulators) {
1993 		ret = -ENOMEM;
1994 		goto err;
1995 	}
1996 
1997 	for (i = 0; i < count; i++) {
1998 		reg = regulator_get_optional(dev, names[i]);
1999 		if (IS_ERR(reg)) {
2000 			ret = PTR_ERR(reg);
2001 			if (ret != -EPROBE_DEFER)
2002 				dev_err(dev, "%s: no regulator (%s) found: %d\n",
2003 					__func__, names[i], ret);
2004 			goto free_regulators;
2005 		}
2006 
2007 		opp_table->regulators[i] = reg;
2008 	}
2009 
2010 	opp_table->regulator_count = count;
2011 
2012 	supplies = kmalloc_array(count * 2, sizeof(*supplies), GFP_KERNEL);
2013 	if (!supplies) {
2014 		ret = -ENOMEM;
2015 		goto free_regulators;
2016 	}
2017 
2018 	mutex_lock(&opp_table->lock);
2019 	opp_table->sod_supplies = supplies;
2020 	if (opp_table->set_opp_data) {
2021 		opp_table->set_opp_data->old_opp.supplies = supplies;
2022 		opp_table->set_opp_data->new_opp.supplies = supplies + count;
2023 	}
2024 	mutex_unlock(&opp_table->lock);
2025 
2026 	return opp_table;
2027 
2028 free_regulators:
2029 	while (i != 0)
2030 		regulator_put(opp_table->regulators[--i]);
2031 
2032 	kfree(opp_table->regulators);
2033 	opp_table->regulators = NULL;
2034 	opp_table->regulator_count = -1;
2035 err:
2036 	dev_pm_opp_put_opp_table(opp_table);
2037 
2038 	return ERR_PTR(ret);
2039 }
2040 EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulators);
2041 
2042 /**
2043  * dev_pm_opp_put_regulators() - Releases resources blocked for regulator
2044  * @opp_table: OPP table returned from dev_pm_opp_set_regulators().
2045  */
dev_pm_opp_put_regulators(struct opp_table * opp_table)2046 void dev_pm_opp_put_regulators(struct opp_table *opp_table)
2047 {
2048 	int i;
2049 
2050 	if (unlikely(!opp_table))
2051 		return;
2052 
2053 	if (!opp_table->regulators)
2054 		goto put_opp_table;
2055 
2056 	if (opp_table->enabled) {
2057 		for (i = opp_table->regulator_count - 1; i >= 0; i--)
2058 			regulator_disable(opp_table->regulators[i]);
2059 	}
2060 
2061 	for (i = opp_table->regulator_count - 1; i >= 0; i--)
2062 		regulator_put(opp_table->regulators[i]);
2063 
2064 	mutex_lock(&opp_table->lock);
2065 	if (opp_table->set_opp_data) {
2066 		opp_table->set_opp_data->old_opp.supplies = NULL;
2067 		opp_table->set_opp_data->new_opp.supplies = NULL;
2068 	}
2069 
2070 	kfree(opp_table->sod_supplies);
2071 	opp_table->sod_supplies = NULL;
2072 	mutex_unlock(&opp_table->lock);
2073 
2074 	kfree(opp_table->regulators);
2075 	opp_table->regulators = NULL;
2076 	opp_table->regulator_count = -1;
2077 
2078 put_opp_table:
2079 	dev_pm_opp_put_opp_table(opp_table);
2080 }
2081 EXPORT_SYMBOL_GPL(dev_pm_opp_put_regulators);
2082 
devm_pm_opp_regulators_release(void * data)2083 static void devm_pm_opp_regulators_release(void *data)
2084 {
2085 	dev_pm_opp_put_regulators(data);
2086 }
2087 
2088 /**
2089  * devm_pm_opp_set_regulators() - Set regulator names for the device
2090  * @dev: Device for which regulator name is being set.
2091  * @names: Array of pointers to the names of the regulator.
2092  * @count: Number of regulators.
2093  *
2094  * This is a resource-managed variant of dev_pm_opp_set_regulators().
2095  *
2096  * Return: 0 on success and errorno otherwise.
2097  */
devm_pm_opp_set_regulators(struct device * dev,const char * const names[],unsigned int count)2098 int devm_pm_opp_set_regulators(struct device *dev,
2099 			       const char * const names[],
2100 			       unsigned int count)
2101 {
2102 	struct opp_table *opp_table;
2103 
2104 	opp_table = dev_pm_opp_set_regulators(dev, names, count);
2105 	if (IS_ERR(opp_table))
2106 		return PTR_ERR(opp_table);
2107 
2108 	return devm_add_action_or_reset(dev, devm_pm_opp_regulators_release,
2109 					opp_table);
2110 }
2111 EXPORT_SYMBOL_GPL(devm_pm_opp_set_regulators);
2112 
2113 /**
2114  * dev_pm_opp_set_clkname() - Set clk name for the device
2115  * @dev: Device for which clk name is being set.
2116  * @name: Clk name.
2117  *
2118  * In order to support OPP switching, OPP layer needs to get pointer to the
2119  * clock for the device. Simple cases work fine without using this routine (i.e.
2120  * by passing connection-id as NULL), but for a device with multiple clocks
2121  * available, the OPP core needs to know the exact name of the clk to use.
2122  *
2123  * This must be called before any OPPs are initialized for the device.
2124  */
dev_pm_opp_set_clkname(struct device * dev,const char * name)2125 struct opp_table *dev_pm_opp_set_clkname(struct device *dev, const char *name)
2126 {
2127 	struct opp_table *opp_table;
2128 	int ret;
2129 
2130 	opp_table = _add_opp_table(dev, false);
2131 	if (IS_ERR(opp_table))
2132 		return opp_table;
2133 
2134 	/* This should be called before OPPs are initialized */
2135 	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
2136 		ret = -EBUSY;
2137 		goto err;
2138 	}
2139 
2140 	/* clk shouldn't be initialized at this point */
2141 	if (WARN_ON(opp_table->clk)) {
2142 		ret = -EBUSY;
2143 		goto err;
2144 	}
2145 
2146 	/* Find clk for the device */
2147 	opp_table->clk = clk_get(dev, name);
2148 	if (IS_ERR(opp_table->clk)) {
2149 		ret = PTR_ERR(opp_table->clk);
2150 		if (ret != -EPROBE_DEFER) {
2151 			dev_err(dev, "%s: Couldn't find clock: %d\n", __func__,
2152 				ret);
2153 		}
2154 		goto err;
2155 	}
2156 
2157 	return opp_table;
2158 
2159 err:
2160 	dev_pm_opp_put_opp_table(opp_table);
2161 
2162 	return ERR_PTR(ret);
2163 }
2164 EXPORT_SYMBOL_GPL(dev_pm_opp_set_clkname);
2165 
2166 /**
2167  * dev_pm_opp_put_clkname() - Releases resources blocked for clk.
2168  * @opp_table: OPP table returned from dev_pm_opp_set_clkname().
2169  */
dev_pm_opp_put_clkname(struct opp_table * opp_table)2170 void dev_pm_opp_put_clkname(struct opp_table *opp_table)
2171 {
2172 	if (unlikely(!opp_table))
2173 		return;
2174 
2175 	clk_put(opp_table->clk);
2176 	opp_table->clk = ERR_PTR(-EINVAL);
2177 
2178 	dev_pm_opp_put_opp_table(opp_table);
2179 }
2180 EXPORT_SYMBOL_GPL(dev_pm_opp_put_clkname);
2181 
devm_pm_opp_clkname_release(void * data)2182 static void devm_pm_opp_clkname_release(void *data)
2183 {
2184 	dev_pm_opp_put_clkname(data);
2185 }
2186 
2187 /**
2188  * devm_pm_opp_set_clkname() - Set clk name for the device
2189  * @dev: Device for which clk name is being set.
2190  * @name: Clk name.
2191  *
2192  * This is a resource-managed variant of dev_pm_opp_set_clkname().
2193  *
2194  * Return: 0 on success and errorno otherwise.
2195  */
devm_pm_opp_set_clkname(struct device * dev,const char * name)2196 int devm_pm_opp_set_clkname(struct device *dev, const char *name)
2197 {
2198 	struct opp_table *opp_table;
2199 
2200 	opp_table = dev_pm_opp_set_clkname(dev, name);
2201 	if (IS_ERR(opp_table))
2202 		return PTR_ERR(opp_table);
2203 
2204 	return devm_add_action_or_reset(dev, devm_pm_opp_clkname_release,
2205 					opp_table);
2206 }
2207 EXPORT_SYMBOL_GPL(devm_pm_opp_set_clkname);
2208 
2209 /**
2210  * dev_pm_opp_register_set_opp_helper() - Register custom set OPP helper
2211  * @dev: Device for which the helper is getting registered.
2212  * @set_opp: Custom set OPP helper.
2213  *
2214  * This is useful to support complex platforms (like platforms with multiple
2215  * regulators per device), instead of the generic OPP set rate helper.
2216  *
2217  * This must be called before any OPPs are initialized for the device.
2218  */
dev_pm_opp_register_set_opp_helper(struct device * dev,int (* set_opp)(struct dev_pm_set_opp_data * data))2219 struct opp_table *dev_pm_opp_register_set_opp_helper(struct device *dev,
2220 			int (*set_opp)(struct dev_pm_set_opp_data *data))
2221 {
2222 	struct dev_pm_set_opp_data *data;
2223 	struct opp_table *opp_table;
2224 
2225 	if (!set_opp)
2226 		return ERR_PTR(-EINVAL);
2227 
2228 	opp_table = _add_opp_table(dev, false);
2229 	if (IS_ERR(opp_table))
2230 		return opp_table;
2231 
2232 	/* This should be called before OPPs are initialized */
2233 	if (WARN_ON(!list_empty(&opp_table->opp_list))) {
2234 		dev_pm_opp_put_opp_table(opp_table);
2235 		return ERR_PTR(-EBUSY);
2236 	}
2237 
2238 	/* Another CPU that shares the OPP table has set the helper ? */
2239 	if (opp_table->set_opp)
2240 		return opp_table;
2241 
2242 	data = kzalloc(sizeof(*data), GFP_KERNEL);
2243 	if (!data)
2244 		return ERR_PTR(-ENOMEM);
2245 
2246 	mutex_lock(&opp_table->lock);
2247 	opp_table->set_opp_data = data;
2248 	if (opp_table->sod_supplies) {
2249 		data->old_opp.supplies = opp_table->sod_supplies;
2250 		data->new_opp.supplies = opp_table->sod_supplies +
2251 					 opp_table->regulator_count;
2252 	}
2253 	mutex_unlock(&opp_table->lock);
2254 
2255 	opp_table->set_opp = set_opp;
2256 
2257 	return opp_table;
2258 }
2259 EXPORT_SYMBOL_GPL(dev_pm_opp_register_set_opp_helper);
2260 
2261 /**
2262  * dev_pm_opp_unregister_set_opp_helper() - Releases resources blocked for
2263  *					   set_opp helper
2264  * @opp_table: OPP table returned from dev_pm_opp_register_set_opp_helper().
2265  *
2266  * Release resources blocked for platform specific set_opp helper.
2267  */
dev_pm_opp_unregister_set_opp_helper(struct opp_table * opp_table)2268 void dev_pm_opp_unregister_set_opp_helper(struct opp_table *opp_table)
2269 {
2270 	if (unlikely(!opp_table))
2271 		return;
2272 
2273 	opp_table->set_opp = NULL;
2274 
2275 	mutex_lock(&opp_table->lock);
2276 	kfree(opp_table->set_opp_data);
2277 	opp_table->set_opp_data = NULL;
2278 	mutex_unlock(&opp_table->lock);
2279 
2280 	dev_pm_opp_put_opp_table(opp_table);
2281 }
2282 EXPORT_SYMBOL_GPL(dev_pm_opp_unregister_set_opp_helper);
2283 
devm_pm_opp_unregister_set_opp_helper(void * data)2284 static void devm_pm_opp_unregister_set_opp_helper(void *data)
2285 {
2286 	dev_pm_opp_unregister_set_opp_helper(data);
2287 }
2288 
2289 /**
2290  * devm_pm_opp_register_set_opp_helper() - Register custom set OPP helper
2291  * @dev: Device for which the helper is getting registered.
2292  * @set_opp: Custom set OPP helper.
2293  *
2294  * This is a resource-managed version of dev_pm_opp_register_set_opp_helper().
2295  *
2296  * Return: 0 on success and errorno otherwise.
2297  */
devm_pm_opp_register_set_opp_helper(struct device * dev,int (* set_opp)(struct dev_pm_set_opp_data * data))2298 int devm_pm_opp_register_set_opp_helper(struct device *dev,
2299 					int (*set_opp)(struct dev_pm_set_opp_data *data))
2300 {
2301 	struct opp_table *opp_table;
2302 
2303 	opp_table = dev_pm_opp_register_set_opp_helper(dev, set_opp);
2304 	if (IS_ERR(opp_table))
2305 		return PTR_ERR(opp_table);
2306 
2307 	return devm_add_action_or_reset(dev, devm_pm_opp_unregister_set_opp_helper,
2308 					opp_table);
2309 }
2310 EXPORT_SYMBOL_GPL(devm_pm_opp_register_set_opp_helper);
2311 
_opp_detach_genpd(struct opp_table * opp_table)2312 static void _opp_detach_genpd(struct opp_table *opp_table)
2313 {
2314 	int index;
2315 
2316 	if (!opp_table->genpd_virt_devs)
2317 		return;
2318 
2319 	for (index = 0; index < opp_table->required_opp_count; index++) {
2320 		if (!opp_table->genpd_virt_devs[index])
2321 			continue;
2322 
2323 		dev_pm_domain_detach(opp_table->genpd_virt_devs[index], false);
2324 		opp_table->genpd_virt_devs[index] = NULL;
2325 	}
2326 
2327 	kfree(opp_table->genpd_virt_devs);
2328 	opp_table->genpd_virt_devs = NULL;
2329 }
2330 
2331 /**
2332  * dev_pm_opp_attach_genpd - Attach genpd(s) for the device and save virtual device pointer
2333  * @dev: Consumer device for which the genpd is getting attached.
2334  * @names: Null terminated array of pointers containing names of genpd to attach.
2335  * @virt_devs: Pointer to return the array of virtual devices.
2336  *
2337  * Multiple generic power domains for a device are supported with the help of
2338  * virtual genpd devices, which are created for each consumer device - genpd
2339  * pair. These are the device structures which are attached to the power domain
2340  * and are required by the OPP core to set the performance state of the genpd.
2341  * The same API also works for the case where single genpd is available and so
2342  * we don't need to support that separately.
2343  *
2344  * This helper will normally be called by the consumer driver of the device
2345  * "dev", as only that has details of the genpd names.
2346  *
2347  * This helper needs to be called once with a list of all genpd to attach.
2348  * Otherwise the original device structure will be used instead by the OPP core.
2349  *
2350  * The order of entries in the names array must match the order in which
2351  * "required-opps" are added in DT.
2352  */
dev_pm_opp_attach_genpd(struct device * dev,const char ** names,struct device *** virt_devs)2353 struct opp_table *dev_pm_opp_attach_genpd(struct device *dev,
2354 		const char **names, struct device ***virt_devs)
2355 {
2356 	struct opp_table *opp_table;
2357 	struct device *virt_dev;
2358 	int index = 0, ret = -EINVAL;
2359 	const char **name = names;
2360 
2361 	opp_table = _add_opp_table(dev, false);
2362 	if (IS_ERR(opp_table))
2363 		return opp_table;
2364 
2365 	if (opp_table->genpd_virt_devs)
2366 		return opp_table;
2367 
2368 	/*
2369 	 * If the genpd's OPP table isn't already initialized, parsing of the
2370 	 * required-opps fail for dev. We should retry this after genpd's OPP
2371 	 * table is added.
2372 	 */
2373 	if (!opp_table->required_opp_count) {
2374 		ret = -EPROBE_DEFER;
2375 		goto put_table;
2376 	}
2377 
2378 	mutex_lock(&opp_table->genpd_virt_dev_lock);
2379 
2380 	opp_table->genpd_virt_devs = kcalloc(opp_table->required_opp_count,
2381 					     sizeof(*opp_table->genpd_virt_devs),
2382 					     GFP_KERNEL);
2383 	if (!opp_table->genpd_virt_devs)
2384 		goto unlock;
2385 
2386 	while (*name) {
2387 		if (index >= opp_table->required_opp_count) {
2388 			dev_err(dev, "Index can't be greater than required-opp-count - 1, %s (%d : %d)\n",
2389 				*name, opp_table->required_opp_count, index);
2390 			goto err;
2391 		}
2392 
2393 		virt_dev = dev_pm_domain_attach_by_name(dev, *name);
2394 		if (IS_ERR_OR_NULL(virt_dev)) {
2395 			ret = virt_dev ? PTR_ERR(virt_dev) : -ENODEV;
2396 			dev_err(dev, "Couldn't attach to pm_domain: %d\n", ret);
2397 			goto err;
2398 		}
2399 
2400 		opp_table->genpd_virt_devs[index] = virt_dev;
2401 		index++;
2402 		name++;
2403 	}
2404 
2405 	if (virt_devs)
2406 		*virt_devs = opp_table->genpd_virt_devs;
2407 	mutex_unlock(&opp_table->genpd_virt_dev_lock);
2408 
2409 	return opp_table;
2410 
2411 err:
2412 	_opp_detach_genpd(opp_table);
2413 unlock:
2414 	mutex_unlock(&opp_table->genpd_virt_dev_lock);
2415 
2416 put_table:
2417 	dev_pm_opp_put_opp_table(opp_table);
2418 
2419 	return ERR_PTR(ret);
2420 }
2421 EXPORT_SYMBOL_GPL(dev_pm_opp_attach_genpd);
2422 
2423 /**
2424  * dev_pm_opp_detach_genpd() - Detach genpd(s) from the device.
2425  * @opp_table: OPP table returned by dev_pm_opp_attach_genpd().
2426  *
2427  * This detaches the genpd(s), resets the virtual device pointers, and puts the
2428  * OPP table.
2429  */
dev_pm_opp_detach_genpd(struct opp_table * opp_table)2430 void dev_pm_opp_detach_genpd(struct opp_table *opp_table)
2431 {
2432 	if (unlikely(!opp_table))
2433 		return;
2434 
2435 	/*
2436 	 * Acquire genpd_virt_dev_lock to make sure virt_dev isn't getting
2437 	 * used in parallel.
2438 	 */
2439 	mutex_lock(&opp_table->genpd_virt_dev_lock);
2440 	_opp_detach_genpd(opp_table);
2441 	mutex_unlock(&opp_table->genpd_virt_dev_lock);
2442 
2443 	dev_pm_opp_put_opp_table(opp_table);
2444 }
2445 EXPORT_SYMBOL_GPL(dev_pm_opp_detach_genpd);
2446 
devm_pm_opp_detach_genpd(void * data)2447 static void devm_pm_opp_detach_genpd(void *data)
2448 {
2449 	dev_pm_opp_detach_genpd(data);
2450 }
2451 
2452 /**
2453  * devm_pm_opp_attach_genpd - Attach genpd(s) for the device and save virtual
2454  *			      device pointer
2455  * @dev: Consumer device for which the genpd is getting attached.
2456  * @names: Null terminated array of pointers containing names of genpd to attach.
2457  * @virt_devs: Pointer to return the array of virtual devices.
2458  *
2459  * This is a resource-managed version of dev_pm_opp_attach_genpd().
2460  *
2461  * Return: 0 on success and errorno otherwise.
2462  */
devm_pm_opp_attach_genpd(struct device * dev,const char ** names,struct device *** virt_devs)2463 int devm_pm_opp_attach_genpd(struct device *dev, const char **names,
2464 			     struct device ***virt_devs)
2465 {
2466 	struct opp_table *opp_table;
2467 
2468 	opp_table = dev_pm_opp_attach_genpd(dev, names, virt_devs);
2469 	if (IS_ERR(opp_table))
2470 		return PTR_ERR(opp_table);
2471 
2472 	return devm_add_action_or_reset(dev, devm_pm_opp_detach_genpd,
2473 					opp_table);
2474 }
2475 EXPORT_SYMBOL_GPL(devm_pm_opp_attach_genpd);
2476 
2477 /**
2478  * dev_pm_opp_xlate_required_opp() - Find required OPP for @src_table OPP.
2479  * @src_table: OPP table which has @dst_table as one of its required OPP table.
2480  * @dst_table: Required OPP table of the @src_table.
2481  * @src_opp: OPP from the @src_table.
2482  *
2483  * This function returns the OPP (present in @dst_table) pointed out by the
2484  * "required-opps" property of the @src_opp (present in @src_table).
2485  *
2486  * The callers are required to call dev_pm_opp_put() for the returned OPP after
2487  * use.
2488  *
2489  * Return: pointer to 'struct dev_pm_opp' on success and errorno otherwise.
2490  */
dev_pm_opp_xlate_required_opp(struct opp_table * src_table,struct opp_table * dst_table,struct dev_pm_opp * src_opp)2491 struct dev_pm_opp *dev_pm_opp_xlate_required_opp(struct opp_table *src_table,
2492 						 struct opp_table *dst_table,
2493 						 struct dev_pm_opp *src_opp)
2494 {
2495 	struct dev_pm_opp *opp, *dest_opp = ERR_PTR(-ENODEV);
2496 	int i;
2497 
2498 	if (!src_table || !dst_table || !src_opp ||
2499 	    !src_table->required_opp_tables)
2500 		return ERR_PTR(-EINVAL);
2501 
2502 	/* required-opps not fully initialized yet */
2503 	if (lazy_linking_pending(src_table))
2504 		return ERR_PTR(-EBUSY);
2505 
2506 	for (i = 0; i < src_table->required_opp_count; i++) {
2507 		if (src_table->required_opp_tables[i] == dst_table) {
2508 			mutex_lock(&src_table->lock);
2509 
2510 			list_for_each_entry(opp, &src_table->opp_list, node) {
2511 				if (opp == src_opp) {
2512 					dest_opp = opp->required_opps[i];
2513 					dev_pm_opp_get(dest_opp);
2514 					break;
2515 				}
2516 			}
2517 
2518 			mutex_unlock(&src_table->lock);
2519 			break;
2520 		}
2521 	}
2522 
2523 	if (IS_ERR(dest_opp)) {
2524 		pr_err("%s: Couldn't find matching OPP (%p: %p)\n", __func__,
2525 		       src_table, dst_table);
2526 	}
2527 
2528 	return dest_opp;
2529 }
2530 EXPORT_SYMBOL_GPL(dev_pm_opp_xlate_required_opp);
2531 
2532 /**
2533  * dev_pm_opp_xlate_performance_state() - Find required OPP's pstate for src_table.
2534  * @src_table: OPP table which has dst_table as one of its required OPP table.
2535  * @dst_table: Required OPP table of the src_table.
2536  * @pstate: Current performance state of the src_table.
2537  *
2538  * This Returns pstate of the OPP (present in @dst_table) pointed out by the
2539  * "required-opps" property of the OPP (present in @src_table) which has
2540  * performance state set to @pstate.
2541  *
2542  * Return: Zero or positive performance state on success, otherwise negative
2543  * value on errors.
2544  */
dev_pm_opp_xlate_performance_state(struct opp_table * src_table,struct opp_table * dst_table,unsigned int pstate)2545 int dev_pm_opp_xlate_performance_state(struct opp_table *src_table,
2546 				       struct opp_table *dst_table,
2547 				       unsigned int pstate)
2548 {
2549 	struct dev_pm_opp *opp;
2550 	int dest_pstate = -EINVAL;
2551 	int i;
2552 
2553 	/*
2554 	 * Normally the src_table will have the "required_opps" property set to
2555 	 * point to one of the OPPs in the dst_table, but in some cases the
2556 	 * genpd and its master have one to one mapping of performance states
2557 	 * and so none of them have the "required-opps" property set. Return the
2558 	 * pstate of the src_table as it is in such cases.
2559 	 */
2560 	if (!src_table || !src_table->required_opp_count)
2561 		return pstate;
2562 
2563 	/* required-opps not fully initialized yet */
2564 	if (lazy_linking_pending(src_table))
2565 		return -EBUSY;
2566 
2567 	for (i = 0; i < src_table->required_opp_count; i++) {
2568 		if (src_table->required_opp_tables[i]->np == dst_table->np)
2569 			break;
2570 	}
2571 
2572 	if (unlikely(i == src_table->required_opp_count)) {
2573 		pr_err("%s: Couldn't find matching OPP table (%p: %p)\n",
2574 		       __func__, src_table, dst_table);
2575 		return -EINVAL;
2576 	}
2577 
2578 	mutex_lock(&src_table->lock);
2579 
2580 	list_for_each_entry(opp, &src_table->opp_list, node) {
2581 		if (opp->pstate == pstate) {
2582 			dest_pstate = opp->required_opps[i]->pstate;
2583 			goto unlock;
2584 		}
2585 	}
2586 
2587 	pr_err("%s: Couldn't find matching OPP (%p: %p)\n", __func__, src_table,
2588 	       dst_table);
2589 
2590 unlock:
2591 	mutex_unlock(&src_table->lock);
2592 
2593 	return dest_pstate;
2594 }
2595 
2596 /**
2597  * dev_pm_opp_add()  - Add an OPP table from a table definitions
2598  * @dev:	device for which we do this operation
2599  * @freq:	Frequency in Hz for this OPP
2600  * @u_volt:	Voltage in uVolts for this OPP
2601  *
2602  * This function adds an opp definition to the opp table and returns status.
2603  * The opp is made available by default and it can be controlled using
2604  * dev_pm_opp_enable/disable functions.
2605  *
2606  * Return:
2607  * 0		On success OR
2608  *		Duplicate OPPs (both freq and volt are same) and opp->available
2609  * -EEXIST	Freq are same and volt are different OR
2610  *		Duplicate OPPs (both freq and volt are same) and !opp->available
2611  * -ENOMEM	Memory allocation failure
2612  */
dev_pm_opp_add(struct device * dev,unsigned long freq,unsigned long u_volt)2613 int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt)
2614 {
2615 	struct opp_table *opp_table;
2616 	int ret;
2617 
2618 	opp_table = _add_opp_table(dev, true);
2619 	if (IS_ERR(opp_table))
2620 		return PTR_ERR(opp_table);
2621 
2622 	/* Fix regulator count for dynamic OPPs */
2623 	opp_table->regulator_count = 1;
2624 
2625 	ret = _opp_add_v1(opp_table, dev, freq, u_volt, true);
2626 	if (ret)
2627 		dev_pm_opp_put_opp_table(opp_table);
2628 
2629 	return ret;
2630 }
2631 EXPORT_SYMBOL_GPL(dev_pm_opp_add);
2632 
2633 /**
2634  * _opp_set_availability() - helper to set the availability of an opp
2635  * @dev:		device for which we do this operation
2636  * @freq:		OPP frequency to modify availability
2637  * @availability_req:	availability status requested for this opp
2638  *
2639  * Set the availability of an OPP, opp_{enable,disable} share a common logic
2640  * which is isolated here.
2641  *
2642  * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
2643  * copy operation, returns 0 if no modification was done OR modification was
2644  * successful.
2645  */
_opp_set_availability(struct device * dev,unsigned long freq,bool availability_req)2646 static int _opp_set_availability(struct device *dev, unsigned long freq,
2647 				 bool availability_req)
2648 {
2649 	struct opp_table *opp_table;
2650 	struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV);
2651 	int r = 0;
2652 
2653 	/* Find the opp_table */
2654 	opp_table = _find_opp_table(dev);
2655 	if (IS_ERR(opp_table)) {
2656 		r = PTR_ERR(opp_table);
2657 		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
2658 		return r;
2659 	}
2660 
2661 	mutex_lock(&opp_table->lock);
2662 
2663 	/* Do we have the frequency? */
2664 	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
2665 		if (tmp_opp->rate == freq) {
2666 			opp = tmp_opp;
2667 			break;
2668 		}
2669 	}
2670 
2671 	if (IS_ERR(opp)) {
2672 		r = PTR_ERR(opp);
2673 		goto unlock;
2674 	}
2675 
2676 	/* Is update really needed? */
2677 	if (opp->available == availability_req)
2678 		goto unlock;
2679 
2680 	opp->available = availability_req;
2681 
2682 	dev_pm_opp_get(opp);
2683 	mutex_unlock(&opp_table->lock);
2684 
2685 	/* Notify the change of the OPP availability */
2686 	if (availability_req)
2687 		blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ENABLE,
2688 					     opp);
2689 	else
2690 		blocking_notifier_call_chain(&opp_table->head,
2691 					     OPP_EVENT_DISABLE, opp);
2692 
2693 	dev_pm_opp_put(opp);
2694 	goto put_table;
2695 
2696 unlock:
2697 	mutex_unlock(&opp_table->lock);
2698 put_table:
2699 	dev_pm_opp_put_opp_table(opp_table);
2700 	return r;
2701 }
2702 
2703 /**
2704  * dev_pm_opp_adjust_voltage() - helper to change the voltage of an OPP
2705  * @dev:		device for which we do this operation
2706  * @freq:		OPP frequency to adjust voltage of
2707  * @u_volt:		new OPP target voltage
2708  * @u_volt_min:		new OPP min voltage
2709  * @u_volt_max:		new OPP max voltage
2710  *
2711  * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
2712  * copy operation, returns 0 if no modifcation was done OR modification was
2713  * successful.
2714  */
dev_pm_opp_adjust_voltage(struct device * dev,unsigned long freq,unsigned long u_volt,unsigned long u_volt_min,unsigned long u_volt_max)2715 int dev_pm_opp_adjust_voltage(struct device *dev, unsigned long freq,
2716 			      unsigned long u_volt, unsigned long u_volt_min,
2717 			      unsigned long u_volt_max)
2718 
2719 {
2720 	struct opp_table *opp_table;
2721 	struct dev_pm_opp *tmp_opp, *opp = ERR_PTR(-ENODEV);
2722 	int r = 0;
2723 
2724 	/* Find the opp_table */
2725 	opp_table = _find_opp_table(dev);
2726 	if (IS_ERR(opp_table)) {
2727 		r = PTR_ERR(opp_table);
2728 		dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r);
2729 		return r;
2730 	}
2731 
2732 	mutex_lock(&opp_table->lock);
2733 
2734 	/* Do we have the frequency? */
2735 	list_for_each_entry(tmp_opp, &opp_table->opp_list, node) {
2736 		if (tmp_opp->rate == freq) {
2737 			opp = tmp_opp;
2738 			break;
2739 		}
2740 	}
2741 
2742 	if (IS_ERR(opp)) {
2743 		r = PTR_ERR(opp);
2744 		goto adjust_unlock;
2745 	}
2746 
2747 	/* Is update really needed? */
2748 	if (opp->supplies->u_volt == u_volt)
2749 		goto adjust_unlock;
2750 
2751 	opp->supplies->u_volt = u_volt;
2752 	opp->supplies->u_volt_min = u_volt_min;
2753 	opp->supplies->u_volt_max = u_volt_max;
2754 
2755 	dev_pm_opp_get(opp);
2756 	mutex_unlock(&opp_table->lock);
2757 
2758 	/* Notify the voltage change of the OPP */
2759 	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADJUST_VOLTAGE,
2760 				     opp);
2761 
2762 	dev_pm_opp_put(opp);
2763 	goto adjust_put_table;
2764 
2765 adjust_unlock:
2766 	mutex_unlock(&opp_table->lock);
2767 adjust_put_table:
2768 	dev_pm_opp_put_opp_table(opp_table);
2769 	return r;
2770 }
2771 EXPORT_SYMBOL_GPL(dev_pm_opp_adjust_voltage);
2772 
2773 /**
2774  * dev_pm_opp_enable() - Enable a specific OPP
2775  * @dev:	device for which we do this operation
2776  * @freq:	OPP frequency to enable
2777  *
2778  * Enables a provided opp. If the operation is valid, this returns 0, else the
2779  * corresponding error value. It is meant to be used for users an OPP available
2780  * after being temporarily made unavailable with dev_pm_opp_disable.
2781  *
2782  * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
2783  * copy operation, returns 0 if no modification was done OR modification was
2784  * successful.
2785  */
dev_pm_opp_enable(struct device * dev,unsigned long freq)2786 int dev_pm_opp_enable(struct device *dev, unsigned long freq)
2787 {
2788 	return _opp_set_availability(dev, freq, true);
2789 }
2790 EXPORT_SYMBOL_GPL(dev_pm_opp_enable);
2791 
2792 /**
2793  * dev_pm_opp_disable() - Disable a specific OPP
2794  * @dev:	device for which we do this operation
2795  * @freq:	OPP frequency to disable
2796  *
2797  * Disables a provided opp. If the operation is valid, this returns
2798  * 0, else the corresponding error value. It is meant to be a temporary
2799  * control by users to make this OPP not available until the circumstances are
2800  * right to make it available again (with a call to dev_pm_opp_enable).
2801  *
2802  * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the
2803  * copy operation, returns 0 if no modification was done OR modification was
2804  * successful.
2805  */
dev_pm_opp_disable(struct device * dev,unsigned long freq)2806 int dev_pm_opp_disable(struct device *dev, unsigned long freq)
2807 {
2808 	return _opp_set_availability(dev, freq, false);
2809 }
2810 EXPORT_SYMBOL_GPL(dev_pm_opp_disable);
2811 
2812 /**
2813  * dev_pm_opp_register_notifier() - Register OPP notifier for the device
2814  * @dev:	Device for which notifier needs to be registered
2815  * @nb:		Notifier block to be registered
2816  *
2817  * Return: 0 on success or a negative error value.
2818  */
dev_pm_opp_register_notifier(struct device * dev,struct notifier_block * nb)2819 int dev_pm_opp_register_notifier(struct device *dev, struct notifier_block *nb)
2820 {
2821 	struct opp_table *opp_table;
2822 	int ret;
2823 
2824 	opp_table = _find_opp_table(dev);
2825 	if (IS_ERR(opp_table))
2826 		return PTR_ERR(opp_table);
2827 
2828 	ret = blocking_notifier_chain_register(&opp_table->head, nb);
2829 
2830 	dev_pm_opp_put_opp_table(opp_table);
2831 
2832 	return ret;
2833 }
2834 EXPORT_SYMBOL(dev_pm_opp_register_notifier);
2835 
2836 /**
2837  * dev_pm_opp_unregister_notifier() - Unregister OPP notifier for the device
2838  * @dev:	Device for which notifier needs to be unregistered
2839  * @nb:		Notifier block to be unregistered
2840  *
2841  * Return: 0 on success or a negative error value.
2842  */
dev_pm_opp_unregister_notifier(struct device * dev,struct notifier_block * nb)2843 int dev_pm_opp_unregister_notifier(struct device *dev,
2844 				   struct notifier_block *nb)
2845 {
2846 	struct opp_table *opp_table;
2847 	int ret;
2848 
2849 	opp_table = _find_opp_table(dev);
2850 	if (IS_ERR(opp_table))
2851 		return PTR_ERR(opp_table);
2852 
2853 	ret = blocking_notifier_chain_unregister(&opp_table->head, nb);
2854 
2855 	dev_pm_opp_put_opp_table(opp_table);
2856 
2857 	return ret;
2858 }
2859 EXPORT_SYMBOL(dev_pm_opp_unregister_notifier);
2860 
2861 /**
2862  * dev_pm_opp_remove_table() - Free all OPPs associated with the device
2863  * @dev:	device pointer used to lookup OPP table.
2864  *
2865  * Free both OPPs created using static entries present in DT and the
2866  * dynamically added entries.
2867  */
dev_pm_opp_remove_table(struct device * dev)2868 void dev_pm_opp_remove_table(struct device *dev)
2869 {
2870 	struct opp_table *opp_table;
2871 
2872 	/* Check for existing table for 'dev' */
2873 	opp_table = _find_opp_table(dev);
2874 	if (IS_ERR(opp_table)) {
2875 		int error = PTR_ERR(opp_table);
2876 
2877 		if (error != -ENODEV)
2878 			WARN(1, "%s: opp_table: %d\n",
2879 			     IS_ERR_OR_NULL(dev) ?
2880 					"Invalid device" : dev_name(dev),
2881 			     error);
2882 		return;
2883 	}
2884 
2885 	/*
2886 	 * Drop the extra reference only if the OPP table was successfully added
2887 	 * with dev_pm_opp_of_add_table() earlier.
2888 	 **/
2889 	if (_opp_remove_all_static(opp_table))
2890 		dev_pm_opp_put_opp_table(opp_table);
2891 
2892 	/* Drop reference taken by _find_opp_table() */
2893 	dev_pm_opp_put_opp_table(opp_table);
2894 }
2895 EXPORT_SYMBOL_GPL(dev_pm_opp_remove_table);
2896 
2897 /**
2898  * dev_pm_opp_sync_regulators() - Sync state of voltage regulators
2899  * @dev:	device for which we do this operation
2900  *
2901  * Sync voltage state of the OPP table regulators.
2902  *
2903  * Return: 0 on success or a negative error value.
2904  */
dev_pm_opp_sync_regulators(struct device * dev)2905 int dev_pm_opp_sync_regulators(struct device *dev)
2906 {
2907 	struct opp_table *opp_table;
2908 	struct regulator *reg;
2909 	int i, ret = 0;
2910 
2911 	/* Device may not have OPP table */
2912 	opp_table = _find_opp_table(dev);
2913 	if (IS_ERR(opp_table))
2914 		return 0;
2915 
2916 	/* Regulator may not be required for the device */
2917 	if (unlikely(!opp_table->regulators))
2918 		goto put_table;
2919 
2920 	/* Nothing to sync if voltage wasn't changed */
2921 	if (!opp_table->enabled)
2922 		goto put_table;
2923 
2924 	for (i = 0; i < opp_table->regulator_count; i++) {
2925 		reg = opp_table->regulators[i];
2926 		ret = regulator_sync_voltage(reg);
2927 		if (ret)
2928 			break;
2929 	}
2930 put_table:
2931 	/* Drop reference taken by _find_opp_table() */
2932 	dev_pm_opp_put_opp_table(opp_table);
2933 
2934 	return ret;
2935 }
2936 EXPORT_SYMBOL_GPL(dev_pm_opp_sync_regulators);
2937