Commit | Line | Data |
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e1f60b29 NM |
1 | /* |
2 | * Generic OPP Interface | |
3 | * | |
4 | * Copyright (C) 2009-2010 Texas Instruments Incorporated. | |
5 | * Nishanth Menon | |
6 | * Romit Dasgupta | |
7 | * Kevin Hilman | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
12 | */ | |
13 | ||
d6d2a528 VK |
14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
15 | ||
e1f60b29 NM |
16 | #include <linux/errno.h> |
17 | #include <linux/err.h> | |
e1f60b29 | 18 | #include <linux/slab.h> |
51990e82 | 19 | #include <linux/device.h> |
b496dfbc | 20 | #include <linux/of.h> |
80126ce7 | 21 | #include <linux/export.h> |
e1f60b29 | 22 | |
f59d3ee8 | 23 | #include "opp.h" |
e1f60b29 NM |
24 | |
25 | /* | |
26 | * The root of the list of all devices. All device_opp structures branch off | |
27 | * from here, with each device_opp containing the list of opp it supports in | |
28 | * various states of availability. | |
29 | */ | |
30 | static LIST_HEAD(dev_opp_list); | |
31 | /* Lock to allow exclusive modification to the device and opp lists */ | |
87b4115d | 32 | DEFINE_MUTEX(dev_opp_list_lock); |
e1f60b29 | 33 | |
b02ded24 DT |
34 | #define opp_rcu_lockdep_assert() \ |
35 | do { \ | |
f78f5b90 PM |
36 | RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ |
37 | !lockdep_is_held(&dev_opp_list_lock), \ | |
b02ded24 DT |
38 | "Missing rcu_read_lock() or " \ |
39 | "dev_opp_list_lock protection"); \ | |
40 | } while (0) | |
41 | ||
06441658 VK |
42 | static struct device_list_opp *_find_list_dev(const struct device *dev, |
43 | struct device_opp *dev_opp) | |
44 | { | |
45 | struct device_list_opp *list_dev; | |
46 | ||
47 | list_for_each_entry(list_dev, &dev_opp->dev_list, node) | |
48 | if (list_dev->dev == dev) | |
49 | return list_dev; | |
50 | ||
51 | return NULL; | |
52 | } | |
53 | ||
54 | static struct device_opp *_managed_opp(const struct device_node *np) | |
55 | { | |
56 | struct device_opp *dev_opp; | |
57 | ||
58 | list_for_each_entry_rcu(dev_opp, &dev_opp_list, node) { | |
59 | if (dev_opp->np == np) { | |
60 | /* | |
61 | * Multiple devices can point to the same OPP table and | |
62 | * so will have same node-pointer, np. | |
63 | * | |
64 | * But the OPPs will be considered as shared only if the | |
65 | * OPP table contains a "opp-shared" property. | |
66 | */ | |
67 | return dev_opp->shared_opp ? dev_opp : NULL; | |
68 | } | |
69 | } | |
70 | ||
71 | return NULL; | |
72 | } | |
73 | ||
e1f60b29 | 74 | /** |
327854c8 | 75 | * _find_device_opp() - find device_opp struct using device pointer |
e1f60b29 NM |
76 | * @dev: device pointer used to lookup device OPPs |
77 | * | |
78 | * Search list of device OPPs for one containing matching device. Does a RCU | |
79 | * reader operation to grab the pointer needed. | |
80 | * | |
984f16c8 | 81 | * Return: pointer to 'struct device_opp' if found, otherwise -ENODEV or |
e1f60b29 NM |
82 | * -EINVAL based on type of error. |
83 | * | |
84 | * Locking: This function must be called under rcu_read_lock(). device_opp | |
85 | * is a RCU protected pointer. This means that device_opp is valid as long | |
86 | * as we are under RCU lock. | |
87 | */ | |
f59d3ee8 | 88 | struct device_opp *_find_device_opp(struct device *dev) |
e1f60b29 | 89 | { |
06441658 | 90 | struct device_opp *dev_opp; |
e1f60b29 | 91 | |
50a3cb04 | 92 | if (IS_ERR_OR_NULL(dev)) { |
e1f60b29 NM |
93 | pr_err("%s: Invalid parameters\n", __func__); |
94 | return ERR_PTR(-EINVAL); | |
95 | } | |
96 | ||
06441658 VK |
97 | list_for_each_entry_rcu(dev_opp, &dev_opp_list, node) |
98 | if (_find_list_dev(dev, dev_opp)) | |
99 | return dev_opp; | |
e1f60b29 | 100 | |
06441658 | 101 | return ERR_PTR(-ENODEV); |
e1f60b29 NM |
102 | } |
103 | ||
104 | /** | |
5d4879cd | 105 | * dev_pm_opp_get_voltage() - Gets the voltage corresponding to an available opp |
e1f60b29 NM |
106 | * @opp: opp for which voltage has to be returned for |
107 | * | |
984f16c8 | 108 | * Return: voltage in micro volt corresponding to the opp, else |
e1f60b29 NM |
109 | * return 0 |
110 | * | |
111 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
112 | * protected pointer. This means that opp which could have been fetched by | |
113 | * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are | |
114 | * under RCU lock. The pointer returned by the opp_find_freq family must be | |
115 | * used in the same section as the usage of this function with the pointer | |
116 | * prior to unlocking with rcu_read_unlock() to maintain the integrity of the | |
117 | * pointer. | |
118 | */ | |
47d43ba7 | 119 | unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) |
e1f60b29 | 120 | { |
47d43ba7 | 121 | struct dev_pm_opp *tmp_opp; |
e1f60b29 NM |
122 | unsigned long v = 0; |
123 | ||
04bf1c7f KK |
124 | opp_rcu_lockdep_assert(); |
125 | ||
e1f60b29 | 126 | tmp_opp = rcu_dereference(opp); |
50a3cb04 | 127 | if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) |
e1f60b29 NM |
128 | pr_err("%s: Invalid parameters\n", __func__); |
129 | else | |
130 | v = tmp_opp->u_volt; | |
131 | ||
132 | return v; | |
133 | } | |
5d4879cd | 134 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage); |
e1f60b29 NM |
135 | |
136 | /** | |
5d4879cd | 137 | * dev_pm_opp_get_freq() - Gets the frequency corresponding to an available opp |
e1f60b29 NM |
138 | * @opp: opp for which frequency has to be returned for |
139 | * | |
984f16c8 | 140 | * Return: frequency in hertz corresponding to the opp, else |
e1f60b29 NM |
141 | * return 0 |
142 | * | |
143 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
144 | * protected pointer. This means that opp which could have been fetched by | |
145 | * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are | |
146 | * under RCU lock. The pointer returned by the opp_find_freq family must be | |
147 | * used in the same section as the usage of this function with the pointer | |
148 | * prior to unlocking with rcu_read_unlock() to maintain the integrity of the | |
149 | * pointer. | |
150 | */ | |
47d43ba7 | 151 | unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp) |
e1f60b29 | 152 | { |
47d43ba7 | 153 | struct dev_pm_opp *tmp_opp; |
e1f60b29 NM |
154 | unsigned long f = 0; |
155 | ||
04bf1c7f KK |
156 | opp_rcu_lockdep_assert(); |
157 | ||
e1f60b29 | 158 | tmp_opp = rcu_dereference(opp); |
50a3cb04 | 159 | if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) |
e1f60b29 NM |
160 | pr_err("%s: Invalid parameters\n", __func__); |
161 | else | |
162 | f = tmp_opp->rate; | |
163 | ||
164 | return f; | |
165 | } | |
5d4879cd | 166 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq); |
e1f60b29 | 167 | |
19445b25 BZ |
168 | /** |
169 | * dev_pm_opp_is_turbo() - Returns if opp is turbo OPP or not | |
170 | * @opp: opp for which turbo mode is being verified | |
171 | * | |
172 | * Turbo OPPs are not for normal use, and can be enabled (under certain | |
173 | * conditions) for short duration of times to finish high throughput work | |
174 | * quickly. Running on them for longer times may overheat the chip. | |
175 | * | |
176 | * Return: true if opp is turbo opp, else false. | |
177 | * | |
178 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
179 | * protected pointer. This means that opp which could have been fetched by | |
180 | * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are | |
181 | * under RCU lock. The pointer returned by the opp_find_freq family must be | |
182 | * used in the same section as the usage of this function with the pointer | |
183 | * prior to unlocking with rcu_read_unlock() to maintain the integrity of the | |
184 | * pointer. | |
185 | */ | |
186 | bool dev_pm_opp_is_turbo(struct dev_pm_opp *opp) | |
187 | { | |
188 | struct dev_pm_opp *tmp_opp; | |
189 | ||
190 | opp_rcu_lockdep_assert(); | |
191 | ||
192 | tmp_opp = rcu_dereference(opp); | |
193 | if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) { | |
194 | pr_err("%s: Invalid parameters\n", __func__); | |
195 | return false; | |
196 | } | |
197 | ||
198 | return tmp_opp->turbo; | |
199 | } | |
200 | EXPORT_SYMBOL_GPL(dev_pm_opp_is_turbo); | |
201 | ||
3ca9bb33 VK |
202 | /** |
203 | * dev_pm_opp_get_max_clock_latency() - Get max clock latency in nanoseconds | |
204 | * @dev: device for which we do this operation | |
205 | * | |
206 | * Return: This function returns the max clock latency in nanoseconds. | |
207 | * | |
208 | * Locking: This function takes rcu_read_lock(). | |
209 | */ | |
210 | unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev) | |
211 | { | |
212 | struct device_opp *dev_opp; | |
213 | unsigned long clock_latency_ns; | |
214 | ||
215 | rcu_read_lock(); | |
216 | ||
217 | dev_opp = _find_device_opp(dev); | |
218 | if (IS_ERR(dev_opp)) | |
219 | clock_latency_ns = 0; | |
220 | else | |
221 | clock_latency_ns = dev_opp->clock_latency_ns_max; | |
222 | ||
223 | rcu_read_unlock(); | |
224 | return clock_latency_ns; | |
225 | } | |
226 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency); | |
227 | ||
4eafbd15 BZ |
228 | /** |
229 | * dev_pm_opp_get_suspend_opp() - Get suspend opp | |
230 | * @dev: device for which we do this operation | |
231 | * | |
232 | * Return: This function returns pointer to the suspend opp if it is | |
1b2b90cb | 233 | * defined and available, otherwise it returns NULL. |
4eafbd15 BZ |
234 | * |
235 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
236 | * protected pointer. The reason for the same is that the opp pointer which is | |
237 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
238 | * under the locked area. The pointer returned must be used prior to unlocking | |
239 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
240 | */ | |
241 | struct dev_pm_opp *dev_pm_opp_get_suspend_opp(struct device *dev) | |
242 | { | |
243 | struct device_opp *dev_opp; | |
4eafbd15 BZ |
244 | |
245 | opp_rcu_lockdep_assert(); | |
246 | ||
247 | dev_opp = _find_device_opp(dev); | |
1b2b90cb VK |
248 | if (IS_ERR(dev_opp) || !dev_opp->suspend_opp || |
249 | !dev_opp->suspend_opp->available) | |
250 | return NULL; | |
4eafbd15 | 251 | |
1b2b90cb | 252 | return dev_opp->suspend_opp; |
4eafbd15 BZ |
253 | } |
254 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_suspend_opp); | |
255 | ||
e1f60b29 | 256 | /** |
5d4879cd | 257 | * dev_pm_opp_get_opp_count() - Get number of opps available in the opp list |
e1f60b29 NM |
258 | * @dev: device for which we do this operation |
259 | * | |
984f16c8 | 260 | * Return: This function returns the number of available opps if there are any, |
e1f60b29 NM |
261 | * else returns 0 if none or the corresponding error value. |
262 | * | |
b4718c02 | 263 | * Locking: This function takes rcu_read_lock(). |
e1f60b29 | 264 | */ |
5d4879cd | 265 | int dev_pm_opp_get_opp_count(struct device *dev) |
e1f60b29 NM |
266 | { |
267 | struct device_opp *dev_opp; | |
47d43ba7 | 268 | struct dev_pm_opp *temp_opp; |
e1f60b29 NM |
269 | int count = 0; |
270 | ||
b4718c02 | 271 | rcu_read_lock(); |
b02ded24 | 272 | |
327854c8 | 273 | dev_opp = _find_device_opp(dev); |
e1f60b29 | 274 | if (IS_ERR(dev_opp)) { |
b4718c02 DT |
275 | count = PTR_ERR(dev_opp); |
276 | dev_err(dev, "%s: device OPP not found (%d)\n", | |
277 | __func__, count); | |
278 | goto out_unlock; | |
e1f60b29 NM |
279 | } |
280 | ||
281 | list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { | |
282 | if (temp_opp->available) | |
283 | count++; | |
284 | } | |
285 | ||
b4718c02 DT |
286 | out_unlock: |
287 | rcu_read_unlock(); | |
e1f60b29 NM |
288 | return count; |
289 | } | |
5d4879cd | 290 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count); |
e1f60b29 NM |
291 | |
292 | /** | |
5d4879cd | 293 | * dev_pm_opp_find_freq_exact() - search for an exact frequency |
e1f60b29 NM |
294 | * @dev: device for which we do this operation |
295 | * @freq: frequency to search for | |
7ae49618 | 296 | * @available: true/false - match for available opp |
e1f60b29 | 297 | * |
984f16c8 NM |
298 | * Return: Searches for exact match in the opp list and returns pointer to the |
299 | * matching opp if found, else returns ERR_PTR in case of error and should | |
300 | * be handled using IS_ERR. Error return values can be: | |
0779726c NM |
301 | * EINVAL: for bad pointer |
302 | * ERANGE: no match found for search | |
303 | * ENODEV: if device not found in list of registered devices | |
e1f60b29 NM |
304 | * |
305 | * Note: available is a modifier for the search. if available=true, then the | |
306 | * match is for exact matching frequency and is available in the stored OPP | |
307 | * table. if false, the match is for exact frequency which is not available. | |
308 | * | |
309 | * This provides a mechanism to enable an opp which is not available currently | |
310 | * or the opposite as well. | |
311 | * | |
312 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
313 | * protected pointer. The reason for the same is that the opp pointer which is | |
314 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
315 | * under the locked area. The pointer returned must be used prior to unlocking | |
316 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
317 | */ | |
47d43ba7 NM |
318 | struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev, |
319 | unsigned long freq, | |
320 | bool available) | |
e1f60b29 NM |
321 | { |
322 | struct device_opp *dev_opp; | |
47d43ba7 | 323 | struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); |
e1f60b29 | 324 | |
b02ded24 DT |
325 | opp_rcu_lockdep_assert(); |
326 | ||
327854c8 | 327 | dev_opp = _find_device_opp(dev); |
e1f60b29 NM |
328 | if (IS_ERR(dev_opp)) { |
329 | int r = PTR_ERR(dev_opp); | |
330 | dev_err(dev, "%s: device OPP not found (%d)\n", __func__, r); | |
331 | return ERR_PTR(r); | |
332 | } | |
333 | ||
334 | list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { | |
335 | if (temp_opp->available == available && | |
336 | temp_opp->rate == freq) { | |
337 | opp = temp_opp; | |
338 | break; | |
339 | } | |
340 | } | |
341 | ||
342 | return opp; | |
343 | } | |
5d4879cd | 344 | EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_exact); |
e1f60b29 NM |
345 | |
346 | /** | |
5d4879cd | 347 | * dev_pm_opp_find_freq_ceil() - Search for an rounded ceil freq |
e1f60b29 NM |
348 | * @dev: device for which we do this operation |
349 | * @freq: Start frequency | |
350 | * | |
351 | * Search for the matching ceil *available* OPP from a starting freq | |
352 | * for a device. | |
353 | * | |
984f16c8 | 354 | * Return: matching *opp and refreshes *freq accordingly, else returns |
0779726c NM |
355 | * ERR_PTR in case of error and should be handled using IS_ERR. Error return |
356 | * values can be: | |
357 | * EINVAL: for bad pointer | |
358 | * ERANGE: no match found for search | |
359 | * ENODEV: if device not found in list of registered devices | |
e1f60b29 NM |
360 | * |
361 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
362 | * protected pointer. The reason for the same is that the opp pointer which is | |
363 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
364 | * under the locked area. The pointer returned must be used prior to unlocking | |
365 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
366 | */ | |
47d43ba7 NM |
367 | struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, |
368 | unsigned long *freq) | |
e1f60b29 NM |
369 | { |
370 | struct device_opp *dev_opp; | |
47d43ba7 | 371 | struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); |
e1f60b29 | 372 | |
b02ded24 DT |
373 | opp_rcu_lockdep_assert(); |
374 | ||
e1f60b29 NM |
375 | if (!dev || !freq) { |
376 | dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); | |
377 | return ERR_PTR(-EINVAL); | |
378 | } | |
379 | ||
327854c8 | 380 | dev_opp = _find_device_opp(dev); |
e1f60b29 | 381 | if (IS_ERR(dev_opp)) |
0779726c | 382 | return ERR_CAST(dev_opp); |
e1f60b29 NM |
383 | |
384 | list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { | |
385 | if (temp_opp->available && temp_opp->rate >= *freq) { | |
386 | opp = temp_opp; | |
387 | *freq = opp->rate; | |
388 | break; | |
389 | } | |
390 | } | |
391 | ||
392 | return opp; | |
393 | } | |
5d4879cd | 394 | EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil); |
e1f60b29 NM |
395 | |
396 | /** | |
5d4879cd | 397 | * dev_pm_opp_find_freq_floor() - Search for a rounded floor freq |
e1f60b29 NM |
398 | * @dev: device for which we do this operation |
399 | * @freq: Start frequency | |
400 | * | |
401 | * Search for the matching floor *available* OPP from a starting freq | |
402 | * for a device. | |
403 | * | |
984f16c8 | 404 | * Return: matching *opp and refreshes *freq accordingly, else returns |
0779726c NM |
405 | * ERR_PTR in case of error and should be handled using IS_ERR. Error return |
406 | * values can be: | |
407 | * EINVAL: for bad pointer | |
408 | * ERANGE: no match found for search | |
409 | * ENODEV: if device not found in list of registered devices | |
e1f60b29 NM |
410 | * |
411 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu | |
412 | * protected pointer. The reason for the same is that the opp pointer which is | |
413 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
414 | * under the locked area. The pointer returned must be used prior to unlocking | |
415 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
416 | */ | |
47d43ba7 NM |
417 | struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, |
418 | unsigned long *freq) | |
e1f60b29 NM |
419 | { |
420 | struct device_opp *dev_opp; | |
47d43ba7 | 421 | struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); |
e1f60b29 | 422 | |
b02ded24 DT |
423 | opp_rcu_lockdep_assert(); |
424 | ||
e1f60b29 NM |
425 | if (!dev || !freq) { |
426 | dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); | |
427 | return ERR_PTR(-EINVAL); | |
428 | } | |
429 | ||
327854c8 | 430 | dev_opp = _find_device_opp(dev); |
e1f60b29 | 431 | if (IS_ERR(dev_opp)) |
0779726c | 432 | return ERR_CAST(dev_opp); |
e1f60b29 NM |
433 | |
434 | list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) { | |
435 | if (temp_opp->available) { | |
436 | /* go to the next node, before choosing prev */ | |
437 | if (temp_opp->rate > *freq) | |
438 | break; | |
439 | else | |
440 | opp = temp_opp; | |
441 | } | |
442 | } | |
443 | if (!IS_ERR(opp)) | |
444 | *freq = opp->rate; | |
445 | ||
446 | return opp; | |
447 | } | |
5d4879cd | 448 | EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor); |
e1f60b29 | 449 | |
06441658 VK |
450 | /* List-dev Helpers */ |
451 | static void _kfree_list_dev_rcu(struct rcu_head *head) | |
452 | { | |
453 | struct device_list_opp *list_dev; | |
454 | ||
455 | list_dev = container_of(head, struct device_list_opp, rcu_head); | |
456 | kfree_rcu(list_dev, rcu_head); | |
457 | } | |
458 | ||
459 | static void _remove_list_dev(struct device_list_opp *list_dev, | |
460 | struct device_opp *dev_opp) | |
461 | { | |
462 | list_del(&list_dev->node); | |
463 | call_srcu(&dev_opp->srcu_head.srcu, &list_dev->rcu_head, | |
464 | _kfree_list_dev_rcu); | |
465 | } | |
466 | ||
f59d3ee8 VK |
467 | struct device_list_opp *_add_list_dev(const struct device *dev, |
468 | struct device_opp *dev_opp) | |
06441658 VK |
469 | { |
470 | struct device_list_opp *list_dev; | |
471 | ||
472 | list_dev = kzalloc(sizeof(*list_dev), GFP_KERNEL); | |
473 | if (!list_dev) | |
474 | return NULL; | |
475 | ||
476 | /* Initialize list-dev */ | |
477 | list_dev->dev = dev; | |
478 | list_add_rcu(&list_dev->node, &dev_opp->dev_list); | |
479 | ||
480 | return list_dev; | |
481 | } | |
482 | ||
984f16c8 | 483 | /** |
aa5f2f85 | 484 | * _add_device_opp() - Find device OPP table or allocate a new one |
984f16c8 NM |
485 | * @dev: device for which we do this operation |
486 | * | |
aa5f2f85 VK |
487 | * It tries to find an existing table first, if it couldn't find one, it |
488 | * allocates a new OPP table and returns that. | |
984f16c8 NM |
489 | * |
490 | * Return: valid device_opp pointer if success, else NULL. | |
491 | */ | |
327854c8 | 492 | static struct device_opp *_add_device_opp(struct device *dev) |
07cce74a VK |
493 | { |
494 | struct device_opp *dev_opp; | |
06441658 | 495 | struct device_list_opp *list_dev; |
07cce74a | 496 | |
aa5f2f85 VK |
497 | /* Check for existing list for 'dev' first */ |
498 | dev_opp = _find_device_opp(dev); | |
499 | if (!IS_ERR(dev_opp)) | |
500 | return dev_opp; | |
07cce74a VK |
501 | |
502 | /* | |
503 | * Allocate a new device OPP table. In the infrequent case where a new | |
504 | * device is needed to be added, we pay this penalty. | |
505 | */ | |
506 | dev_opp = kzalloc(sizeof(*dev_opp), GFP_KERNEL); | |
507 | if (!dev_opp) | |
508 | return NULL; | |
509 | ||
06441658 VK |
510 | INIT_LIST_HEAD(&dev_opp->dev_list); |
511 | ||
512 | list_dev = _add_list_dev(dev, dev_opp); | |
513 | if (!list_dev) { | |
514 | kfree(dev_opp); | |
515 | return NULL; | |
516 | } | |
517 | ||
07cce74a VK |
518 | srcu_init_notifier_head(&dev_opp->srcu_head); |
519 | INIT_LIST_HEAD(&dev_opp->opp_list); | |
520 | ||
521 | /* Secure the device list modification */ | |
522 | list_add_rcu(&dev_opp->node, &dev_opp_list); | |
523 | return dev_opp; | |
524 | } | |
525 | ||
984f16c8 | 526 | /** |
737002b5 VK |
527 | * _kfree_device_rcu() - Free device_opp RCU handler |
528 | * @head: RCU head | |
984f16c8 | 529 | */ |
737002b5 | 530 | static void _kfree_device_rcu(struct rcu_head *head) |
e1f60b29 | 531 | { |
737002b5 | 532 | struct device_opp *device_opp = container_of(head, struct device_opp, rcu_head); |
6ce4184d | 533 | |
737002b5 | 534 | kfree_rcu(device_opp, rcu_head); |
e1f60b29 | 535 | } |
38393409 VK |
536 | |
537 | /** | |
3bac42ca VK |
538 | * _remove_device_opp() - Removes a device OPP table |
539 | * @dev_opp: device OPP table to be removed. | |
38393409 | 540 | * |
3bac42ca | 541 | * Removes/frees device OPP table it it doesn't contain any OPPs. |
38393409 | 542 | */ |
3bac42ca | 543 | static void _remove_device_opp(struct device_opp *dev_opp) |
38393409 | 544 | { |
06441658 VK |
545 | struct device_list_opp *list_dev; |
546 | ||
3bac42ca VK |
547 | if (!list_empty(&dev_opp->opp_list)) |
548 | return; | |
549 | ||
06441658 VK |
550 | list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, |
551 | node); | |
552 | ||
553 | _remove_list_dev(list_dev, dev_opp); | |
554 | ||
555 | /* dev_list must be empty now */ | |
556 | WARN_ON(!list_empty(&dev_opp->dev_list)); | |
557 | ||
3bac42ca VK |
558 | list_del_rcu(&dev_opp->node); |
559 | call_srcu(&dev_opp->srcu_head.srcu, &dev_opp->rcu_head, | |
560 | _kfree_device_rcu); | |
38393409 | 561 | } |
e1f60b29 | 562 | |
984f16c8 NM |
563 | /** |
564 | * _kfree_opp_rcu() - Free OPP RCU handler | |
565 | * @head: RCU head | |
566 | */ | |
327854c8 | 567 | static void _kfree_opp_rcu(struct rcu_head *head) |
129eec55 VK |
568 | { |
569 | struct dev_pm_opp *opp = container_of(head, struct dev_pm_opp, rcu_head); | |
570 | ||
571 | kfree_rcu(opp, rcu_head); | |
572 | } | |
573 | ||
984f16c8 NM |
574 | /** |
575 | * _opp_remove() - Remove an OPP from a table definition | |
576 | * @dev_opp: points back to the device_opp struct this opp belongs to | |
577 | * @opp: pointer to the OPP to remove | |
23dacf6d | 578 | * @notify: OPP_EVENT_REMOVE notification should be sent or not |
984f16c8 NM |
579 | * |
580 | * This function removes an opp definition from the opp list. | |
581 | * | |
582 | * Locking: The internal device_opp and opp structures are RCU protected. | |
583 | * It is assumed that the caller holds required mutex for an RCU updater | |
584 | * strategy. | |
585 | */ | |
327854c8 | 586 | static void _opp_remove(struct device_opp *dev_opp, |
23dacf6d | 587 | struct dev_pm_opp *opp, bool notify) |
129eec55 VK |
588 | { |
589 | /* | |
590 | * Notify the changes in the availability of the operable | |
591 | * frequency/voltage list. | |
592 | */ | |
23dacf6d VK |
593 | if (notify) |
594 | srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); | |
129eec55 | 595 | list_del_rcu(&opp->node); |
327854c8 | 596 | call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu); |
129eec55 | 597 | |
3bac42ca | 598 | _remove_device_opp(dev_opp); |
129eec55 VK |
599 | } |
600 | ||
601 | /** | |
602 | * dev_pm_opp_remove() - Remove an OPP from OPP list | |
603 | * @dev: device for which we do this operation | |
604 | * @freq: OPP to remove with matching 'freq' | |
605 | * | |
606 | * This function removes an opp from the opp list. | |
984f16c8 NM |
607 | * |
608 | * Locking: The internal device_opp and opp structures are RCU protected. | |
609 | * Hence this function internally uses RCU updater strategy with mutex locks | |
610 | * to keep the integrity of the internal data structures. Callers should ensure | |
611 | * that this function is *NOT* called under RCU protection or in contexts where | |
612 | * mutex cannot be locked. | |
129eec55 VK |
613 | */ |
614 | void dev_pm_opp_remove(struct device *dev, unsigned long freq) | |
615 | { | |
616 | struct dev_pm_opp *opp; | |
617 | struct device_opp *dev_opp; | |
618 | bool found = false; | |
619 | ||
620 | /* Hold our list modification lock here */ | |
621 | mutex_lock(&dev_opp_list_lock); | |
622 | ||
327854c8 | 623 | dev_opp = _find_device_opp(dev); |
129eec55 VK |
624 | if (IS_ERR(dev_opp)) |
625 | goto unlock; | |
626 | ||
627 | list_for_each_entry(opp, &dev_opp->opp_list, node) { | |
628 | if (opp->rate == freq) { | |
629 | found = true; | |
630 | break; | |
631 | } | |
632 | } | |
633 | ||
634 | if (!found) { | |
635 | dev_warn(dev, "%s: Couldn't find OPP with freq: %lu\n", | |
636 | __func__, freq); | |
637 | goto unlock; | |
638 | } | |
639 | ||
23dacf6d | 640 | _opp_remove(dev_opp, opp, true); |
129eec55 VK |
641 | unlock: |
642 | mutex_unlock(&dev_opp_list_lock); | |
643 | } | |
644 | EXPORT_SYMBOL_GPL(dev_pm_opp_remove); | |
645 | ||
23dacf6d VK |
646 | static struct dev_pm_opp *_allocate_opp(struct device *dev, |
647 | struct device_opp **dev_opp) | |
e1f60b29 | 648 | { |
23dacf6d | 649 | struct dev_pm_opp *opp; |
e1f60b29 | 650 | |
23dacf6d VK |
651 | /* allocate new OPP node */ |
652 | opp = kzalloc(sizeof(*opp), GFP_KERNEL); | |
653 | if (!opp) | |
654 | return NULL; | |
e1f60b29 | 655 | |
23dacf6d | 656 | INIT_LIST_HEAD(&opp->node); |
e1f60b29 | 657 | |
23dacf6d VK |
658 | *dev_opp = _add_device_opp(dev); |
659 | if (!*dev_opp) { | |
660 | kfree(opp); | |
661 | return NULL; | |
662 | } | |
663 | ||
664 | return opp; | |
665 | } | |
666 | ||
06441658 VK |
667 | static int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, |
668 | struct device_opp *dev_opp) | |
23dacf6d VK |
669 | { |
670 | struct dev_pm_opp *opp; | |
671 | struct list_head *head = &dev_opp->opp_list; | |
672 | ||
673 | /* | |
674 | * Insert new OPP in order of increasing frequency and discard if | |
675 | * already present. | |
676 | * | |
677 | * Need to use &dev_opp->opp_list in the condition part of the 'for' | |
678 | * loop, don't replace it with head otherwise it will become an infinite | |
679 | * loop. | |
680 | */ | |
681 | list_for_each_entry_rcu(opp, &dev_opp->opp_list, node) { | |
682 | if (new_opp->rate > opp->rate) { | |
683 | head = &opp->node; | |
684 | continue; | |
685 | } | |
686 | ||
687 | if (new_opp->rate < opp->rate) | |
688 | break; | |
689 | ||
690 | /* Duplicate OPPs */ | |
06441658 | 691 | dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n", |
23dacf6d VK |
692 | __func__, opp->rate, opp->u_volt, opp->available, |
693 | new_opp->rate, new_opp->u_volt, new_opp->available); | |
694 | ||
695 | return opp->available && new_opp->u_volt == opp->u_volt ? | |
696 | 0 : -EEXIST; | |
697 | } | |
698 | ||
699 | new_opp->dev_opp = dev_opp; | |
700 | list_add_rcu(&new_opp->node, head); | |
701 | ||
702 | return 0; | |
703 | } | |
704 | ||
984f16c8 | 705 | /** |
b64b9c3f | 706 | * _opp_add_v1() - Allocate a OPP based on v1 bindings. |
984f16c8 NM |
707 | * @dev: device for which we do this operation |
708 | * @freq: Frequency in Hz for this OPP | |
709 | * @u_volt: Voltage in uVolts for this OPP | |
710 | * @dynamic: Dynamically added OPPs. | |
711 | * | |
712 | * This function adds an opp definition to the opp list and returns status. | |
713 | * The opp is made available by default and it can be controlled using | |
714 | * dev_pm_opp_enable/disable functions and may be removed by dev_pm_opp_remove. | |
715 | * | |
8f8d37b2 VK |
716 | * NOTE: "dynamic" parameter impacts OPPs added by the dev_pm_opp_of_add_table |
717 | * and freed by dev_pm_opp_of_remove_table. | |
984f16c8 NM |
718 | * |
719 | * Locking: The internal device_opp and opp structures are RCU protected. | |
720 | * Hence this function internally uses RCU updater strategy with mutex locks | |
721 | * to keep the integrity of the internal data structures. Callers should ensure | |
722 | * that this function is *NOT* called under RCU protection or in contexts where | |
723 | * mutex cannot be locked. | |
724 | * | |
725 | * Return: | |
726 | * 0 On success OR | |
727 | * Duplicate OPPs (both freq and volt are same) and opp->available | |
728 | * -EEXIST Freq are same and volt are different OR | |
729 | * Duplicate OPPs (both freq and volt are same) and !opp->available | |
730 | * -ENOMEM Memory allocation failure | |
731 | */ | |
b64b9c3f VK |
732 | static int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt, |
733 | bool dynamic) | |
e1f60b29 | 734 | { |
aa5f2f85 | 735 | struct device_opp *dev_opp; |
23dacf6d | 736 | struct dev_pm_opp *new_opp; |
6ce4184d | 737 | int ret; |
e1f60b29 | 738 | |
e1f60b29 NM |
739 | /* Hold our list modification lock here */ |
740 | mutex_lock(&dev_opp_list_lock); | |
741 | ||
23dacf6d VK |
742 | new_opp = _allocate_opp(dev, &dev_opp); |
743 | if (!new_opp) { | |
744 | ret = -ENOMEM; | |
745 | goto unlock; | |
746 | } | |
747 | ||
a7470db6 | 748 | /* populate the opp table */ |
a7470db6 VK |
749 | new_opp->rate = freq; |
750 | new_opp->u_volt = u_volt; | |
751 | new_opp->available = true; | |
23dacf6d | 752 | new_opp->dynamic = dynamic; |
a7470db6 | 753 | |
06441658 | 754 | ret = _opp_add(dev, new_opp, dev_opp); |
23dacf6d | 755 | if (ret) |
6ce4184d | 756 | goto free_opp; |
64ce8545 | 757 | |
e1f60b29 NM |
758 | mutex_unlock(&dev_opp_list_lock); |
759 | ||
03ca370f MH |
760 | /* |
761 | * Notify the changes in the availability of the operable | |
762 | * frequency/voltage list. | |
763 | */ | |
cd1a068a | 764 | srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADD, new_opp); |
e1f60b29 | 765 | return 0; |
6ce4184d VK |
766 | |
767 | free_opp: | |
23dacf6d VK |
768 | _opp_remove(dev_opp, new_opp, false); |
769 | unlock: | |
6ce4184d | 770 | mutex_unlock(&dev_opp_list_lock); |
6ce4184d | 771 | return ret; |
e1f60b29 | 772 | } |
38393409 | 773 | |
27465902 | 774 | /* TODO: Support multiple regulators */ |
ad623c31 | 775 | static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) |
27465902 VK |
776 | { |
777 | u32 microvolt[3] = {0}; | |
ad623c31 | 778 | u32 val; |
27465902 VK |
779 | int count, ret; |
780 | ||
781 | count = of_property_count_u32_elems(opp->np, "opp-microvolt"); | |
782 | if (!count) | |
783 | return 0; | |
784 | ||
785 | /* There can be one or three elements here */ | |
786 | if (count != 1 && count != 3) { | |
787 | dev_err(dev, "%s: Invalid number of elements in opp-microvolt property (%d)\n", | |
788 | __func__, count); | |
789 | return -EINVAL; | |
790 | } | |
791 | ||
792 | ret = of_property_read_u32_array(opp->np, "opp-microvolt", microvolt, | |
793 | count); | |
794 | if (ret) { | |
795 | dev_err(dev, "%s: error parsing opp-microvolt: %d\n", __func__, | |
796 | ret); | |
797 | return -EINVAL; | |
798 | } | |
799 | ||
800 | opp->u_volt = microvolt[0]; | |
801 | opp->u_volt_min = microvolt[1]; | |
802 | opp->u_volt_max = microvolt[2]; | |
803 | ||
ad623c31 VK |
804 | if (!of_property_read_u32(opp->np, "opp-microamp", &val)) |
805 | opp->u_amp = val; | |
806 | ||
27465902 VK |
807 | return 0; |
808 | } | |
809 | ||
810 | /** | |
811 | * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings) | |
812 | * @dev: device for which we do this operation | |
813 | * @np: device node | |
814 | * | |
815 | * This function adds an opp definition to the opp list and returns status. The | |
816 | * opp can be controlled using dev_pm_opp_enable/disable functions and may be | |
817 | * removed by dev_pm_opp_remove. | |
818 | * | |
819 | * Locking: The internal device_opp and opp structures are RCU protected. | |
820 | * Hence this function internally uses RCU updater strategy with mutex locks | |
821 | * to keep the integrity of the internal data structures. Callers should ensure | |
822 | * that this function is *NOT* called under RCU protection or in contexts where | |
823 | * mutex cannot be locked. | |
824 | * | |
825 | * Return: | |
826 | * 0 On success OR | |
827 | * Duplicate OPPs (both freq and volt are same) and opp->available | |
828 | * -EEXIST Freq are same and volt are different OR | |
829 | * Duplicate OPPs (both freq and volt are same) and !opp->available | |
830 | * -ENOMEM Memory allocation failure | |
831 | * -EINVAL Failed parsing the OPP node | |
832 | */ | |
833 | static int _opp_add_static_v2(struct device *dev, struct device_node *np) | |
834 | { | |
835 | struct device_opp *dev_opp; | |
836 | struct dev_pm_opp *new_opp; | |
837 | u64 rate; | |
68fa9f0a | 838 | u32 val; |
27465902 VK |
839 | int ret; |
840 | ||
841 | /* Hold our list modification lock here */ | |
842 | mutex_lock(&dev_opp_list_lock); | |
843 | ||
844 | new_opp = _allocate_opp(dev, &dev_opp); | |
845 | if (!new_opp) { | |
846 | ret = -ENOMEM; | |
847 | goto unlock; | |
848 | } | |
849 | ||
850 | ret = of_property_read_u64(np, "opp-hz", &rate); | |
851 | if (ret < 0) { | |
852 | dev_err(dev, "%s: opp-hz not found\n", __func__); | |
853 | goto free_opp; | |
854 | } | |
855 | ||
856 | /* | |
857 | * Rate is defined as an unsigned long in clk API, and so casting | |
858 | * explicitly to its type. Must be fixed once rate is 64 bit | |
859 | * guaranteed in clk API. | |
860 | */ | |
861 | new_opp->rate = (unsigned long)rate; | |
862 | new_opp->turbo = of_property_read_bool(np, "turbo-mode"); | |
863 | ||
864 | new_opp->np = np; | |
865 | new_opp->dynamic = false; | |
866 | new_opp->available = true; | |
68fa9f0a VK |
867 | |
868 | if (!of_property_read_u32(np, "clock-latency-ns", &val)) | |
869 | new_opp->clock_latency_ns = val; | |
27465902 | 870 | |
ad623c31 | 871 | ret = opp_parse_supplies(new_opp, dev); |
27465902 VK |
872 | if (ret) |
873 | goto free_opp; | |
874 | ||
06441658 | 875 | ret = _opp_add(dev, new_opp, dev_opp); |
27465902 VK |
876 | if (ret) |
877 | goto free_opp; | |
878 | ||
ad656a6a VK |
879 | /* OPP to select on device suspend */ |
880 | if (of_property_read_bool(np, "opp-suspend")) { | |
881 | if (dev_opp->suspend_opp) | |
882 | dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n", | |
883 | __func__, dev_opp->suspend_opp->rate, | |
884 | new_opp->rate); | |
885 | else | |
886 | dev_opp->suspend_opp = new_opp; | |
887 | } | |
888 | ||
3ca9bb33 VK |
889 | if (new_opp->clock_latency_ns > dev_opp->clock_latency_ns_max) |
890 | dev_opp->clock_latency_ns_max = new_opp->clock_latency_ns; | |
891 | ||
27465902 VK |
892 | mutex_unlock(&dev_opp_list_lock); |
893 | ||
3ca9bb33 | 894 | pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n", |
27465902 | 895 | __func__, new_opp->turbo, new_opp->rate, new_opp->u_volt, |
3ca9bb33 VK |
896 | new_opp->u_volt_min, new_opp->u_volt_max, |
897 | new_opp->clock_latency_ns); | |
27465902 VK |
898 | |
899 | /* | |
900 | * Notify the changes in the availability of the operable | |
901 | * frequency/voltage list. | |
902 | */ | |
903 | srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ADD, new_opp); | |
904 | return 0; | |
905 | ||
906 | free_opp: | |
907 | _opp_remove(dev_opp, new_opp, false); | |
908 | unlock: | |
909 | mutex_unlock(&dev_opp_list_lock); | |
910 | return ret; | |
911 | } | |
912 | ||
38393409 VK |
913 | /** |
914 | * dev_pm_opp_add() - Add an OPP table from a table definitions | |
915 | * @dev: device for which we do this operation | |
916 | * @freq: Frequency in Hz for this OPP | |
917 | * @u_volt: Voltage in uVolts for this OPP | |
918 | * | |
919 | * This function adds an opp definition to the opp list and returns status. | |
920 | * The opp is made available by default and it can be controlled using | |
921 | * dev_pm_opp_enable/disable functions. | |
922 | * | |
923 | * Locking: The internal device_opp and opp structures are RCU protected. | |
924 | * Hence this function internally uses RCU updater strategy with mutex locks | |
925 | * to keep the integrity of the internal data structures. Callers should ensure | |
926 | * that this function is *NOT* called under RCU protection or in contexts where | |
927 | * mutex cannot be locked. | |
928 | * | |
929 | * Return: | |
984f16c8 | 930 | * 0 On success OR |
38393409 | 931 | * Duplicate OPPs (both freq and volt are same) and opp->available |
984f16c8 | 932 | * -EEXIST Freq are same and volt are different OR |
38393409 | 933 | * Duplicate OPPs (both freq and volt are same) and !opp->available |
984f16c8 | 934 | * -ENOMEM Memory allocation failure |
38393409 VK |
935 | */ |
936 | int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) | |
937 | { | |
b64b9c3f | 938 | return _opp_add_v1(dev, freq, u_volt, true); |
38393409 | 939 | } |
5d4879cd | 940 | EXPORT_SYMBOL_GPL(dev_pm_opp_add); |
e1f60b29 NM |
941 | |
942 | /** | |
327854c8 | 943 | * _opp_set_availability() - helper to set the availability of an opp |
e1f60b29 NM |
944 | * @dev: device for which we do this operation |
945 | * @freq: OPP frequency to modify availability | |
946 | * @availability_req: availability status requested for this opp | |
947 | * | |
948 | * Set the availability of an OPP with an RCU operation, opp_{enable,disable} | |
949 | * share a common logic which is isolated here. | |
950 | * | |
984f16c8 | 951 | * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the |
e1f60b29 NM |
952 | * copy operation, returns 0 if no modifcation was done OR modification was |
953 | * successful. | |
954 | * | |
955 | * Locking: The internal device_opp and opp structures are RCU protected. | |
956 | * Hence this function internally uses RCU updater strategy with mutex locks to | |
957 | * keep the integrity of the internal data structures. Callers should ensure | |
958 | * that this function is *NOT* called under RCU protection or in contexts where | |
959 | * mutex locking or synchronize_rcu() blocking calls cannot be used. | |
960 | */ | |
327854c8 NM |
961 | static int _opp_set_availability(struct device *dev, unsigned long freq, |
962 | bool availability_req) | |
e1f60b29 | 963 | { |
29df0ee1 | 964 | struct device_opp *dev_opp; |
47d43ba7 | 965 | struct dev_pm_opp *new_opp, *tmp_opp, *opp = ERR_PTR(-ENODEV); |
e1f60b29 NM |
966 | int r = 0; |
967 | ||
968 | /* keep the node allocated */ | |
47d43ba7 | 969 | new_opp = kmalloc(sizeof(*new_opp), GFP_KERNEL); |
59d84ca8 | 970 | if (!new_opp) |
e1f60b29 | 971 | return -ENOMEM; |
e1f60b29 NM |
972 | |
973 | mutex_lock(&dev_opp_list_lock); | |
974 | ||
975 | /* Find the device_opp */ | |
327854c8 | 976 | dev_opp = _find_device_opp(dev); |
e1f60b29 NM |
977 | if (IS_ERR(dev_opp)) { |
978 | r = PTR_ERR(dev_opp); | |
979 | dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r); | |
980 | goto unlock; | |
981 | } | |
982 | ||
983 | /* Do we have the frequency? */ | |
984 | list_for_each_entry(tmp_opp, &dev_opp->opp_list, node) { | |
985 | if (tmp_opp->rate == freq) { | |
986 | opp = tmp_opp; | |
987 | break; | |
988 | } | |
989 | } | |
990 | if (IS_ERR(opp)) { | |
991 | r = PTR_ERR(opp); | |
992 | goto unlock; | |
993 | } | |
994 | ||
995 | /* Is update really needed? */ | |
996 | if (opp->available == availability_req) | |
997 | goto unlock; | |
998 | /* copy the old data over */ | |
999 | *new_opp = *opp; | |
1000 | ||
1001 | /* plug in new node */ | |
1002 | new_opp->available = availability_req; | |
1003 | ||
1004 | list_replace_rcu(&opp->node, &new_opp->node); | |
1005 | mutex_unlock(&dev_opp_list_lock); | |
327854c8 | 1006 | call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu); |
e1f60b29 | 1007 | |
03ca370f MH |
1008 | /* Notify the change of the OPP availability */ |
1009 | if (availability_req) | |
cd1a068a | 1010 | srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_ENABLE, |
03ca370f MH |
1011 | new_opp); |
1012 | else | |
cd1a068a | 1013 | srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_DISABLE, |
03ca370f MH |
1014 | new_opp); |
1015 | ||
dde8437d | 1016 | return 0; |
e1f60b29 NM |
1017 | |
1018 | unlock: | |
1019 | mutex_unlock(&dev_opp_list_lock); | |
e1f60b29 NM |
1020 | kfree(new_opp); |
1021 | return r; | |
1022 | } | |
1023 | ||
1024 | /** | |
5d4879cd | 1025 | * dev_pm_opp_enable() - Enable a specific OPP |
e1f60b29 NM |
1026 | * @dev: device for which we do this operation |
1027 | * @freq: OPP frequency to enable | |
1028 | * | |
1029 | * Enables a provided opp. If the operation is valid, this returns 0, else the | |
1030 | * corresponding error value. It is meant to be used for users an OPP available | |
5d4879cd | 1031 | * after being temporarily made unavailable with dev_pm_opp_disable. |
e1f60b29 NM |
1032 | * |
1033 | * Locking: The internal device_opp and opp structures are RCU protected. | |
1034 | * Hence this function indirectly uses RCU and mutex locks to keep the | |
1035 | * integrity of the internal data structures. Callers should ensure that | |
1036 | * this function is *NOT* called under RCU protection or in contexts where | |
1037 | * mutex locking or synchronize_rcu() blocking calls cannot be used. | |
984f16c8 NM |
1038 | * |
1039 | * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the | |
1040 | * copy operation, returns 0 if no modifcation was done OR modification was | |
1041 | * successful. | |
e1f60b29 | 1042 | */ |
5d4879cd | 1043 | int dev_pm_opp_enable(struct device *dev, unsigned long freq) |
e1f60b29 | 1044 | { |
327854c8 | 1045 | return _opp_set_availability(dev, freq, true); |
e1f60b29 | 1046 | } |
5d4879cd | 1047 | EXPORT_SYMBOL_GPL(dev_pm_opp_enable); |
e1f60b29 NM |
1048 | |
1049 | /** | |
5d4879cd | 1050 | * dev_pm_opp_disable() - Disable a specific OPP |
e1f60b29 NM |
1051 | * @dev: device for which we do this operation |
1052 | * @freq: OPP frequency to disable | |
1053 | * | |
1054 | * Disables a provided opp. If the operation is valid, this returns | |
1055 | * 0, else the corresponding error value. It is meant to be a temporary | |
1056 | * control by users to make this OPP not available until the circumstances are | |
5d4879cd | 1057 | * right to make it available again (with a call to dev_pm_opp_enable). |
e1f60b29 NM |
1058 | * |
1059 | * Locking: The internal device_opp and opp structures are RCU protected. | |
1060 | * Hence this function indirectly uses RCU and mutex locks to keep the | |
1061 | * integrity of the internal data structures. Callers should ensure that | |
1062 | * this function is *NOT* called under RCU protection or in contexts where | |
1063 | * mutex locking or synchronize_rcu() blocking calls cannot be used. | |
984f16c8 NM |
1064 | * |
1065 | * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the | |
1066 | * copy operation, returns 0 if no modifcation was done OR modification was | |
1067 | * successful. | |
e1f60b29 | 1068 | */ |
5d4879cd | 1069 | int dev_pm_opp_disable(struct device *dev, unsigned long freq) |
e1f60b29 | 1070 | { |
327854c8 | 1071 | return _opp_set_availability(dev, freq, false); |
e1f60b29 | 1072 | } |
5d4879cd | 1073 | EXPORT_SYMBOL_GPL(dev_pm_opp_disable); |
e1f60b29 | 1074 | |
03ca370f | 1075 | /** |
5d4879cd | 1076 | * dev_pm_opp_get_notifier() - find notifier_head of the device with opp |
03ca370f | 1077 | * @dev: device pointer used to lookup device OPPs. |
984f16c8 NM |
1078 | * |
1079 | * Return: pointer to notifier head if found, otherwise -ENODEV or | |
1080 | * -EINVAL based on type of error casted as pointer. value must be checked | |
1081 | * with IS_ERR to determine valid pointer or error result. | |
1082 | * | |
1083 | * Locking: This function must be called under rcu_read_lock(). dev_opp is a RCU | |
1084 | * protected pointer. The reason for the same is that the opp pointer which is | |
1085 | * returned will remain valid for use with opp_get_{voltage, freq} only while | |
1086 | * under the locked area. The pointer returned must be used prior to unlocking | |
1087 | * with rcu_read_unlock() to maintain the integrity of the pointer. | |
03ca370f | 1088 | */ |
5d4879cd | 1089 | struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev) |
03ca370f | 1090 | { |
327854c8 | 1091 | struct device_opp *dev_opp = _find_device_opp(dev); |
03ca370f MH |
1092 | |
1093 | if (IS_ERR(dev_opp)) | |
156acb16 | 1094 | return ERR_CAST(dev_opp); /* matching type */ |
03ca370f | 1095 | |
cd1a068a | 1096 | return &dev_opp->srcu_head; |
03ca370f | 1097 | } |
4679ec37 | 1098 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier); |
b496dfbc SG |
1099 | |
1100 | #ifdef CONFIG_OF | |
1101 | /** | |
8f8d37b2 VK |
1102 | * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT |
1103 | * entries | |
b496dfbc SG |
1104 | * @dev: device pointer used to lookup device OPPs. |
1105 | * | |
737002b5 | 1106 | * Free OPPs created using static entries present in DT. |
984f16c8 NM |
1107 | * |
1108 | * Locking: The internal device_opp and opp structures are RCU protected. | |
1109 | * Hence this function indirectly uses RCU updater strategy with mutex locks | |
1110 | * to keep the integrity of the internal data structures. Callers should ensure | |
1111 | * that this function is *NOT* called under RCU protection or in contexts where | |
1112 | * mutex cannot be locked. | |
b496dfbc | 1113 | */ |
8f8d37b2 | 1114 | void dev_pm_opp_of_remove_table(struct device *dev) |
737002b5 VK |
1115 | { |
1116 | struct device_opp *dev_opp; | |
1117 | struct dev_pm_opp *opp, *tmp; | |
1118 | ||
06441658 VK |
1119 | /* Hold our list modification lock here */ |
1120 | mutex_lock(&dev_opp_list_lock); | |
1121 | ||
737002b5 VK |
1122 | /* Check for existing list for 'dev' */ |
1123 | dev_opp = _find_device_opp(dev); | |
1124 | if (IS_ERR(dev_opp)) { | |
1125 | int error = PTR_ERR(dev_opp); | |
1126 | ||
1127 | if (error != -ENODEV) | |
1128 | WARN(1, "%s: dev_opp: %d\n", | |
1129 | IS_ERR_OR_NULL(dev) ? | |
1130 | "Invalid device" : dev_name(dev), | |
1131 | error); | |
06441658 | 1132 | goto unlock; |
737002b5 VK |
1133 | } |
1134 | ||
06441658 VK |
1135 | /* Find if dev_opp manages a single device */ |
1136 | if (list_is_singular(&dev_opp->dev_list)) { | |
1137 | /* Free static OPPs */ | |
1138 | list_for_each_entry_safe(opp, tmp, &dev_opp->opp_list, node) { | |
1139 | if (!opp->dynamic) | |
1140 | _opp_remove(dev_opp, opp, true); | |
1141 | } | |
1142 | } else { | |
1143 | _remove_list_dev(_find_list_dev(dev, dev_opp), dev_opp); | |
737002b5 VK |
1144 | } |
1145 | ||
06441658 | 1146 | unlock: |
737002b5 VK |
1147 | mutex_unlock(&dev_opp_list_lock); |
1148 | } | |
8f8d37b2 | 1149 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table); |
737002b5 | 1150 | |
1840995c | 1151 | /* Returns opp descriptor node for a device, caller must do of_node_put() */ |
f59d3ee8 | 1152 | struct device_node *_of_get_opp_desc_node(struct device *dev) |
8d4d4e98 | 1153 | { |
8d4d4e98 VK |
1154 | /* |
1155 | * TODO: Support for multiple OPP tables. | |
1156 | * | |
1157 | * There should be only ONE phandle present in "operating-points-v2" | |
1158 | * property. | |
1159 | */ | |
8d4d4e98 | 1160 | |
1840995c | 1161 | return of_parse_phandle(dev->of_node, "operating-points-v2", 0); |
8d4d4e98 VK |
1162 | } |
1163 | ||
27465902 | 1164 | /* Initializes OPP tables based on new bindings */ |
f0489a5e | 1165 | static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np) |
27465902 | 1166 | { |
1840995c | 1167 | struct device_node *np; |
06441658 | 1168 | struct device_opp *dev_opp; |
27465902 VK |
1169 | int ret = 0, count = 0; |
1170 | ||
4a3a1353 VK |
1171 | mutex_lock(&dev_opp_list_lock); |
1172 | ||
06441658 VK |
1173 | dev_opp = _managed_opp(opp_np); |
1174 | if (dev_opp) { | |
1175 | /* OPPs are already managed */ | |
1176 | if (!_add_list_dev(dev, dev_opp)) | |
1177 | ret = -ENOMEM; | |
4a3a1353 | 1178 | mutex_unlock(&dev_opp_list_lock); |
1840995c | 1179 | return ret; |
06441658 | 1180 | } |
4a3a1353 | 1181 | mutex_unlock(&dev_opp_list_lock); |
06441658 | 1182 | |
27465902 VK |
1183 | /* We have opp-list node now, iterate over it and add OPPs */ |
1184 | for_each_available_child_of_node(opp_np, np) { | |
1185 | count++; | |
1186 | ||
1187 | ret = _opp_add_static_v2(dev, np); | |
1188 | if (ret) { | |
1189 | dev_err(dev, "%s: Failed to add OPP, %d\n", __func__, | |
1190 | ret); | |
1f821ed7 | 1191 | goto free_table; |
27465902 VK |
1192 | } |
1193 | } | |
1194 | ||
1195 | /* There should be one of more OPP defined */ | |
1840995c VK |
1196 | if (WARN_ON(!count)) |
1197 | return -ENOENT; | |
27465902 | 1198 | |
4a3a1353 VK |
1199 | mutex_lock(&dev_opp_list_lock); |
1200 | ||
1f821ed7 VK |
1201 | dev_opp = _find_device_opp(dev); |
1202 | if (WARN_ON(IS_ERR(dev_opp))) { | |
1203 | ret = PTR_ERR(dev_opp); | |
4a3a1353 | 1204 | mutex_unlock(&dev_opp_list_lock); |
1f821ed7 | 1205 | goto free_table; |
06441658 | 1206 | } |
27465902 | 1207 | |
1f821ed7 VK |
1208 | dev_opp->np = opp_np; |
1209 | dev_opp->shared_opp = of_property_read_bool(opp_np, "opp-shared"); | |
1210 | ||
4a3a1353 VK |
1211 | mutex_unlock(&dev_opp_list_lock); |
1212 | ||
1f821ed7 VK |
1213 | return 0; |
1214 | ||
1215 | free_table: | |
8f8d37b2 | 1216 | dev_pm_opp_of_remove_table(dev); |
27465902 VK |
1217 | |
1218 | return ret; | |
1219 | } | |
1220 | ||
1221 | /* Initializes OPP tables based on old-deprecated bindings */ | |
f0489a5e | 1222 | static int _of_add_opp_table_v1(struct device *dev) |
b496dfbc SG |
1223 | { |
1224 | const struct property *prop; | |
1225 | const __be32 *val; | |
1226 | int nr; | |
1227 | ||
1228 | prop = of_find_property(dev->of_node, "operating-points", NULL); | |
1229 | if (!prop) | |
1230 | return -ENODEV; | |
1231 | if (!prop->value) | |
1232 | return -ENODATA; | |
1233 | ||
1234 | /* | |
1235 | * Each OPP is a set of tuples consisting of frequency and | |
1236 | * voltage like <freq-kHz vol-uV>. | |
1237 | */ | |
1238 | nr = prop->length / sizeof(u32); | |
1239 | if (nr % 2) { | |
1240 | dev_err(dev, "%s: Invalid OPP list\n", __func__); | |
1241 | return -EINVAL; | |
1242 | } | |
1243 | ||
1244 | val = prop->value; | |
1245 | while (nr) { | |
1246 | unsigned long freq = be32_to_cpup(val++) * 1000; | |
1247 | unsigned long volt = be32_to_cpup(val++); | |
1248 | ||
b64b9c3f | 1249 | if (_opp_add_v1(dev, freq, volt, false)) |
b496dfbc SG |
1250 | dev_warn(dev, "%s: Failed to add OPP %ld\n", |
1251 | __func__, freq); | |
b496dfbc SG |
1252 | nr -= 2; |
1253 | } | |
1254 | ||
1255 | return 0; | |
1256 | } | |
129eec55 VK |
1257 | |
1258 | /** | |
8f8d37b2 | 1259 | * dev_pm_opp_of_add_table() - Initialize opp table from device tree |
129eec55 VK |
1260 | * @dev: device pointer used to lookup device OPPs. |
1261 | * | |
27465902 | 1262 | * Register the initial OPP table with the OPP library for given device. |
984f16c8 NM |
1263 | * |
1264 | * Locking: The internal device_opp and opp structures are RCU protected. | |
1265 | * Hence this function indirectly uses RCU updater strategy with mutex locks | |
1266 | * to keep the integrity of the internal data structures. Callers should ensure | |
1267 | * that this function is *NOT* called under RCU protection or in contexts where | |
1268 | * mutex cannot be locked. | |
27465902 VK |
1269 | * |
1270 | * Return: | |
1271 | * 0 On success OR | |
1272 | * Duplicate OPPs (both freq and volt are same) and opp->available | |
1273 | * -EEXIST Freq are same and volt are different OR | |
1274 | * Duplicate OPPs (both freq and volt are same) and !opp->available | |
1275 | * -ENOMEM Memory allocation failure | |
1276 | * -ENODEV when 'operating-points' property is not found or is invalid data | |
1277 | * in device node. | |
1278 | * -ENODATA when empty 'operating-points' property is found | |
1279 | * -EINVAL when invalid entries are found in opp-v2 table | |
129eec55 | 1280 | */ |
8f8d37b2 | 1281 | int dev_pm_opp_of_add_table(struct device *dev) |
129eec55 | 1282 | { |
1840995c VK |
1283 | struct device_node *opp_np; |
1284 | int ret; | |
27465902 VK |
1285 | |
1286 | /* | |
1287 | * OPPs have two version of bindings now. The older one is deprecated, | |
1288 | * try for the new binding first. | |
1289 | */ | |
1840995c VK |
1290 | opp_np = _of_get_opp_desc_node(dev); |
1291 | if (!opp_np) { | |
27465902 VK |
1292 | /* |
1293 | * Try old-deprecated bindings for backward compatibility with | |
1294 | * older dtbs. | |
1295 | */ | |
f0489a5e | 1296 | return _of_add_opp_table_v1(dev); |
27465902 VK |
1297 | } |
1298 | ||
f0489a5e | 1299 | ret = _of_add_opp_table_v2(dev, opp_np); |
1840995c VK |
1300 | of_node_put(opp_np); |
1301 | ||
1302 | return ret; | |
27465902 | 1303 | } |
8f8d37b2 | 1304 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table); |
b496dfbc | 1305 | #endif |