Commit | Line | Data |
---|---|---|
5de363b6 | 1 | // SPDX-License-Identifier: GPL-2.0 |
91ff4cb8 JP |
2 | /* |
3 | * Devices PM QoS constraints management | |
4 | * | |
5 | * Copyright (C) 2011 Texas Instruments, Inc. | |
6 | * | |
91ff4cb8 JP |
7 | * This module exposes the interface to kernel space for specifying |
8 | * per-device PM QoS dependencies. It provides infrastructure for registration | |
9 | * of: | |
10 | * | |
11 | * Dependents on a QoS value : register requests | |
12 | * Watchers of QoS value : get notified when target QoS value changes | |
13 | * | |
14 | * This QoS design is best effort based. Dependents register their QoS needs. | |
15 | * Watchers register to keep track of the current QoS needs of the system. | |
d08d1b27 VK |
16 | * Watchers can register a per-device notification callback using the |
17 | * dev_pm_qos_*_notifier API. The notification chain data is stored in the | |
18 | * per-device constraint data struct. | |
91ff4cb8 JP |
19 | * |
20 | * Note about the per-device constraint data struct allocation: | |
07a6c71b | 21 | * . The per-device constraints data struct ptr is stored into the device |
91ff4cb8 JP |
22 | * dev_pm_info. |
23 | * . To minimize the data usage by the per-device constraints, the data struct | |
24 | * is only allocated at the first call to dev_pm_qos_add_request. | |
25 | * . The data is later free'd when the device is removed from the system. | |
91ff4cb8 JP |
26 | * . A global mutex protects the constraints users from the data being |
27 | * allocated and free'd. | |
28 | */ | |
29 | ||
30 | #include <linux/pm_qos.h> | |
31 | #include <linux/spinlock.h> | |
32 | #include <linux/slab.h> | |
33 | #include <linux/device.h> | |
34 | #include <linux/mutex.h> | |
1b6bc32f | 35 | #include <linux/export.h> |
e39473d0 | 36 | #include <linux/pm_runtime.h> |
37530f2b | 37 | #include <linux/err.h> |
96d9d0b5 | 38 | #include <trace/events/power.h> |
91ff4cb8 | 39 | |
85dc0b8a | 40 | #include "power.h" |
91ff4cb8 JP |
41 | |
42 | static DEFINE_MUTEX(dev_pm_qos_mtx); | |
0f703069 | 43 | static DEFINE_MUTEX(dev_pm_qos_sysfs_mtx); |
1a9a9152 | 44 | |
ae0fb4b7 RW |
45 | /** |
46 | * __dev_pm_qos_flags - Check PM QoS flags for a given device. | |
47 | * @dev: Device to check the PM QoS flags for. | |
48 | * @mask: Flags to check against. | |
49 | * | |
50 | * This routine must be called with dev->power.lock held. | |
51 | */ | |
52 | enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask) | |
53 | { | |
54 | struct dev_pm_qos *qos = dev->power.qos; | |
55 | struct pm_qos_flags *pqf; | |
56 | s32 val; | |
57 | ||
f90b8ad8 KK |
58 | lockdep_assert_held(&dev->power.lock); |
59 | ||
37530f2b | 60 | if (IS_ERR_OR_NULL(qos)) |
ae0fb4b7 RW |
61 | return PM_QOS_FLAGS_UNDEFINED; |
62 | ||
63 | pqf = &qos->flags; | |
64 | if (list_empty(&pqf->list)) | |
65 | return PM_QOS_FLAGS_UNDEFINED; | |
66 | ||
67 | val = pqf->effective_flags & mask; | |
68 | if (val) | |
69 | return (val == mask) ? PM_QOS_FLAGS_ALL : PM_QOS_FLAGS_SOME; | |
70 | ||
71 | return PM_QOS_FLAGS_NONE; | |
72 | } | |
73 | ||
74 | /** | |
75 | * dev_pm_qos_flags - Check PM QoS flags for a given device (locked). | |
76 | * @dev: Device to check the PM QoS flags for. | |
77 | * @mask: Flags to check against. | |
78 | */ | |
79 | enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask) | |
80 | { | |
81 | unsigned long irqflags; | |
82 | enum pm_qos_flags_status ret; | |
83 | ||
84 | spin_lock_irqsave(&dev->power.lock, irqflags); | |
85 | ret = __dev_pm_qos_flags(dev, mask); | |
86 | spin_unlock_irqrestore(&dev->power.lock, irqflags); | |
87 | ||
88 | return ret; | |
89 | } | |
6802771b | 90 | EXPORT_SYMBOL_GPL(dev_pm_qos_flags); |
ae0fb4b7 | 91 | |
1a9a9152 | 92 | /** |
8262331e | 93 | * __dev_pm_qos_resume_latency - Get resume latency constraint for a given device. |
00dc9ad1 RW |
94 | * @dev: Device to get the PM QoS constraint value for. |
95 | * | |
96 | * This routine must be called with dev->power.lock held. | |
97 | */ | |
8262331e | 98 | s32 __dev_pm_qos_resume_latency(struct device *dev) |
00dc9ad1 | 99 | { |
f90b8ad8 KK |
100 | lockdep_assert_held(&dev->power.lock); |
101 | ||
8262331e | 102 | return dev_pm_qos_raw_resume_latency(dev); |
00dc9ad1 RW |
103 | } |
104 | ||
105 | /** | |
106 | * dev_pm_qos_read_value - Get PM QoS constraint for a given device (locked). | |
1a9a9152 | 107 | * @dev: Device to get the PM QoS constraint value for. |
2a79ea5e | 108 | * @type: QoS request type. |
1a9a9152 | 109 | */ |
2a79ea5e | 110 | s32 dev_pm_qos_read_value(struct device *dev, enum dev_pm_qos_req_type type) |
1a9a9152 | 111 | { |
2a79ea5e | 112 | struct dev_pm_qos *qos = dev->power.qos; |
1a9a9152 | 113 | unsigned long flags; |
00dc9ad1 | 114 | s32 ret; |
1a9a9152 RW |
115 | |
116 | spin_lock_irqsave(&dev->power.lock, flags); | |
8262331e | 117 | |
36a8015f LC |
118 | switch (type) { |
119 | case DEV_PM_QOS_RESUME_LATENCY: | |
2a79ea5e VK |
120 | ret = IS_ERR_OR_NULL(qos) ? PM_QOS_RESUME_LATENCY_NO_CONSTRAINT |
121 | : pm_qos_read_value(&qos->resume_latency); | |
36a8015f LC |
122 | break; |
123 | case DEV_PM_QOS_MIN_FREQUENCY: | |
124 | ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE | |
125 | : freq_qos_read_value(&qos->freq, FREQ_QOS_MIN); | |
126 | break; | |
127 | case DEV_PM_QOS_MAX_FREQUENCY: | |
128 | ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE | |
129 | : freq_qos_read_value(&qos->freq, FREQ_QOS_MAX); | |
130 | break; | |
131 | default: | |
2a79ea5e VK |
132 | WARN_ON(1); |
133 | ret = 0; | |
134 | } | |
8262331e | 135 | |
1a9a9152 RW |
136 | spin_unlock_irqrestore(&dev->power.lock, flags); |
137 | ||
138 | return ret; | |
139 | } | |
140 | ||
ae0fb4b7 RW |
141 | /** |
142 | * apply_constraint - Add/modify/remove device PM QoS request. | |
143 | * @req: Constraint request to apply | |
144 | * @action: Action to perform (add/update/remove). | |
145 | * @value: Value to assign to the QoS request. | |
b66213cd JP |
146 | * |
147 | * Internal function to update the constraints list using the PM QoS core | |
d08d1b27 | 148 | * code and if needed call the per-device callbacks. |
b66213cd JP |
149 | */ |
150 | static int apply_constraint(struct dev_pm_qos_request *req, | |
ae0fb4b7 | 151 | enum pm_qos_req_action action, s32 value) |
b66213cd | 152 | { |
ae0fb4b7 RW |
153 | struct dev_pm_qos *qos = req->dev->power.qos; |
154 | int ret; | |
b66213cd | 155 | |
ae0fb4b7 | 156 | switch(req->type) { |
b02f6695 | 157 | case DEV_PM_QOS_RESUME_LATENCY: |
0759e80b RW |
158 | if (WARN_ON(action != PM_QOS_REMOVE_REQ && value < 0)) |
159 | value = 0; | |
160 | ||
b02f6695 RW |
161 | ret = pm_qos_update_target(&qos->resume_latency, |
162 | &req->data.pnode, action, value); | |
ae0fb4b7 | 163 | break; |
2d984ad1 RW |
164 | case DEV_PM_QOS_LATENCY_TOLERANCE: |
165 | ret = pm_qos_update_target(&qos->latency_tolerance, | |
166 | &req->data.pnode, action, value); | |
167 | if (ret) { | |
168 | value = pm_qos_read_value(&qos->latency_tolerance); | |
169 | req->dev->power.set_latency_tolerance(req->dev, value); | |
170 | } | |
171 | break; | |
36a8015f LC |
172 | case DEV_PM_QOS_MIN_FREQUENCY: |
173 | case DEV_PM_QOS_MAX_FREQUENCY: | |
174 | ret = freq_qos_apply(&req->data.freq, action, value); | |
175 | break; | |
ae0fb4b7 RW |
176 | case DEV_PM_QOS_FLAGS: |
177 | ret = pm_qos_update_flags(&qos->flags, &req->data.flr, | |
178 | action, value); | |
179 | break; | |
180 | default: | |
181 | ret = -EINVAL; | |
b66213cd JP |
182 | } |
183 | ||
184 | return ret; | |
185 | } | |
91ff4cb8 JP |
186 | |
187 | /* | |
188 | * dev_pm_qos_constraints_allocate | |
189 | * @dev: device to allocate data for | |
190 | * | |
191 | * Called at the first call to add_request, for constraint data allocation | |
192 | * Must be called with the dev_pm_qos_mtx mutex held | |
193 | */ | |
194 | static int dev_pm_qos_constraints_allocate(struct device *dev) | |
195 | { | |
5f986c59 | 196 | struct dev_pm_qos *qos; |
91ff4cb8 JP |
197 | struct pm_qos_constraints *c; |
198 | struct blocking_notifier_head *n; | |
199 | ||
5f986c59 RW |
200 | qos = kzalloc(sizeof(*qos), GFP_KERNEL); |
201 | if (!qos) | |
91ff4cb8 JP |
202 | return -ENOMEM; |
203 | ||
022e6f51 | 204 | n = kcalloc(3, sizeof(*n), GFP_KERNEL); |
91ff4cb8 | 205 | if (!n) { |
5f986c59 | 206 | kfree(qos); |
91ff4cb8 JP |
207 | return -ENOMEM; |
208 | } | |
91ff4cb8 | 209 | |
b02f6695 | 210 | c = &qos->resume_latency; |
1a9a9152 | 211 | plist_head_init(&c->list); |
b02f6695 RW |
212 | c->target_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; |
213 | c->default_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; | |
0759e80b | 214 | c->no_constraint_value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; |
1a9a9152 RW |
215 | c->type = PM_QOS_MIN; |
216 | c->notifiers = n; | |
208637b3 | 217 | BLOCKING_INIT_NOTIFIER_HEAD(n); |
1a9a9152 | 218 | |
2d984ad1 RW |
219 | c = &qos->latency_tolerance; |
220 | plist_head_init(&c->list); | |
221 | c->target_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE; | |
222 | c->default_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE; | |
223 | c->no_constraint_value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; | |
224 | c->type = PM_QOS_MIN; | |
225 | ||
36a8015f LC |
226 | freq_constraints_init(&qos->freq); |
227 | ||
ae0fb4b7 RW |
228 | INIT_LIST_HEAD(&qos->flags.list); |
229 | ||
1a9a9152 | 230 | spin_lock_irq(&dev->power.lock); |
5f986c59 | 231 | dev->power.qos = qos; |
1a9a9152 | 232 | spin_unlock_irq(&dev->power.lock); |
91ff4cb8 JP |
233 | |
234 | return 0; | |
235 | } | |
236 | ||
37530f2b RW |
237 | static void __dev_pm_qos_hide_latency_limit(struct device *dev); |
238 | static void __dev_pm_qos_hide_flags(struct device *dev); | |
91ff4cb8 JP |
239 | |
240 | /** | |
241 | * dev_pm_qos_constraints_destroy | |
242 | * @dev: target device | |
243 | * | |
1a9a9152 | 244 | * Called from the device PM subsystem on device removal under device_pm_lock(). |
91ff4cb8 JP |
245 | */ |
246 | void dev_pm_qos_constraints_destroy(struct device *dev) | |
247 | { | |
5f986c59 | 248 | struct dev_pm_qos *qos; |
91ff4cb8 | 249 | struct dev_pm_qos_request *req, *tmp; |
1a9a9152 | 250 | struct pm_qos_constraints *c; |
35546bd4 | 251 | struct pm_qos_flags *f; |
91ff4cb8 | 252 | |
0f703069 | 253 | mutex_lock(&dev_pm_qos_sysfs_mtx); |
37530f2b | 254 | |
85dc0b8a | 255 | /* |
35546bd4 RW |
256 | * If the device's PM QoS resume latency limit or PM QoS flags have been |
257 | * exposed to user space, they have to be hidden at this point. | |
85dc0b8a | 258 | */ |
b02f6695 | 259 | pm_qos_sysfs_remove_resume_latency(dev); |
0f703069 RW |
260 | pm_qos_sysfs_remove_flags(dev); |
261 | ||
262 | mutex_lock(&dev_pm_qos_mtx); | |
263 | ||
37530f2b RW |
264 | __dev_pm_qos_hide_latency_limit(dev); |
265 | __dev_pm_qos_hide_flags(dev); | |
91ff4cb8 | 266 | |
5f986c59 RW |
267 | qos = dev->power.qos; |
268 | if (!qos) | |
1a9a9152 | 269 | goto out; |
91ff4cb8 | 270 | |
35546bd4 | 271 | /* Flush the constraints lists for the device. */ |
b02f6695 | 272 | c = &qos->resume_latency; |
021c870b | 273 | plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) { |
1a9a9152 RW |
274 | /* |
275 | * Update constraints list and call the notification | |
276 | * callbacks if needed | |
277 | */ | |
278 | apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); | |
279 | memset(req, 0, sizeof(*req)); | |
91ff4cb8 | 280 | } |
208637b3 | 281 | |
2d984ad1 RW |
282 | c = &qos->latency_tolerance; |
283 | plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) { | |
284 | apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); | |
285 | memset(req, 0, sizeof(*req)); | |
286 | } | |
208637b3 | 287 | |
36a8015f LC |
288 | c = &qos->freq.min_freq; |
289 | plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) { | |
290 | apply_constraint(req, PM_QOS_REMOVE_REQ, | |
291 | PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE); | |
292 | memset(req, 0, sizeof(*req)); | |
293 | } | |
294 | ||
295 | c = &qos->freq.max_freq; | |
296 | plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) { | |
297 | apply_constraint(req, PM_QOS_REMOVE_REQ, | |
298 | PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE); | |
299 | memset(req, 0, sizeof(*req)); | |
300 | } | |
301 | ||
35546bd4 RW |
302 | f = &qos->flags; |
303 | list_for_each_entry_safe(req, tmp, &f->list, data.flr.node) { | |
304 | apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); | |
305 | memset(req, 0, sizeof(*req)); | |
91ff4cb8 | 306 | } |
91ff4cb8 | 307 | |
1a9a9152 | 308 | spin_lock_irq(&dev->power.lock); |
37530f2b | 309 | dev->power.qos = ERR_PTR(-ENODEV); |
1a9a9152 RW |
310 | spin_unlock_irq(&dev->power.lock); |
311 | ||
e84b4a84 | 312 | kfree(qos->resume_latency.notifiers); |
9eaee2cd | 313 | kfree(qos); |
1a9a9152 RW |
314 | |
315 | out: | |
91ff4cb8 | 316 | mutex_unlock(&dev_pm_qos_mtx); |
0f703069 RW |
317 | |
318 | mutex_unlock(&dev_pm_qos_sysfs_mtx); | |
91ff4cb8 JP |
319 | } |
320 | ||
41ba8bd0 JS |
321 | static bool dev_pm_qos_invalid_req_type(struct device *dev, |
322 | enum dev_pm_qos_req_type type) | |
2d984ad1 | 323 | { |
41ba8bd0 JS |
324 | return type == DEV_PM_QOS_LATENCY_TOLERANCE && |
325 | !dev->power.set_latency_tolerance; | |
2d984ad1 RW |
326 | } |
327 | ||
328 | static int __dev_pm_qos_add_request(struct device *dev, | |
329 | struct dev_pm_qos_request *req, | |
330 | enum dev_pm_qos_req_type type, s32 value) | |
331 | { | |
332 | int ret = 0; | |
333 | ||
41ba8bd0 | 334 | if (!dev || !req || dev_pm_qos_invalid_req_type(dev, type)) |
2d984ad1 RW |
335 | return -EINVAL; |
336 | ||
337 | if (WARN(dev_pm_qos_request_active(req), | |
338 | "%s() called for already added request\n", __func__)) | |
339 | return -EINVAL; | |
340 | ||
341 | if (IS_ERR(dev->power.qos)) | |
342 | ret = -ENODEV; | |
343 | else if (!dev->power.qos) | |
344 | ret = dev_pm_qos_constraints_allocate(dev); | |
345 | ||
346 | trace_dev_pm_qos_add_request(dev_name(dev), type, value); | |
36a8015f LC |
347 | if (ret) |
348 | return ret; | |
349 | ||
350 | req->dev = dev; | |
351 | req->type = type; | |
352 | if (req->type == DEV_PM_QOS_MIN_FREQUENCY) | |
353 | ret = freq_qos_add_request(&dev->power.qos->freq, | |
354 | &req->data.freq, | |
355 | FREQ_QOS_MIN, value); | |
356 | else if (req->type == DEV_PM_QOS_MAX_FREQUENCY) | |
357 | ret = freq_qos_add_request(&dev->power.qos->freq, | |
358 | &req->data.freq, | |
359 | FREQ_QOS_MAX, value); | |
360 | else | |
2d984ad1 | 361 | ret = apply_constraint(req, PM_QOS_ADD_REQ, value); |
36a8015f | 362 | |
2d984ad1 RW |
363 | return ret; |
364 | } | |
365 | ||
91ff4cb8 JP |
366 | /** |
367 | * dev_pm_qos_add_request - inserts new qos request into the list | |
368 | * @dev: target device for the constraint | |
369 | * @req: pointer to a preallocated handle | |
ae0fb4b7 | 370 | * @type: type of the request |
91ff4cb8 JP |
371 | * @value: defines the qos request |
372 | * | |
373 | * This function inserts a new entry in the device constraints list of | |
374 | * requested qos performance characteristics. It recomputes the aggregate | |
375 | * QoS expectations of parameters and initializes the dev_pm_qos_request | |
376 | * handle. Caller needs to save this handle for later use in updates and | |
377 | * removal. | |
378 | * | |
379 | * Returns 1 if the aggregated constraint value has changed, | |
380 | * 0 if the aggregated constraint value has not changed, | |
1a9a9152 RW |
381 | * -EINVAL in case of wrong parameters, -ENOMEM if there's not enough memory |
382 | * to allocate for data structures, -ENODEV if the device has just been removed | |
383 | * from the system. | |
436ede89 RW |
384 | * |
385 | * Callers should ensure that the target device is not RPM_SUSPENDED before | |
386 | * using this function for requests of type DEV_PM_QOS_FLAGS. | |
91ff4cb8 JP |
387 | */ |
388 | int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, | |
ae0fb4b7 | 389 | enum dev_pm_qos_req_type type, s32 value) |
91ff4cb8 | 390 | { |
2d984ad1 | 391 | int ret; |
91ff4cb8 | 392 | |
1a9a9152 | 393 | mutex_lock(&dev_pm_qos_mtx); |
2d984ad1 | 394 | ret = __dev_pm_qos_add_request(dev, req, type, value); |
91ff4cb8 JP |
395 | mutex_unlock(&dev_pm_qos_mtx); |
396 | return ret; | |
397 | } | |
398 | EXPORT_SYMBOL_GPL(dev_pm_qos_add_request); | |
399 | ||
e39473d0 RW |
400 | /** |
401 | * __dev_pm_qos_update_request - Modify an existing device PM QoS request. | |
402 | * @req : PM QoS request to modify. | |
403 | * @new_value: New value to request. | |
404 | */ | |
405 | static int __dev_pm_qos_update_request(struct dev_pm_qos_request *req, | |
406 | s32 new_value) | |
407 | { | |
408 | s32 curr_value; | |
409 | int ret = 0; | |
410 | ||
b81ea1b5 RW |
411 | if (!req) /*guard against callers passing in null */ |
412 | return -EINVAL; | |
413 | ||
414 | if (WARN(!dev_pm_qos_request_active(req), | |
415 | "%s() called for unknown object\n", __func__)) | |
416 | return -EINVAL; | |
417 | ||
37530f2b | 418 | if (IS_ERR_OR_NULL(req->dev->power.qos)) |
e39473d0 RW |
419 | return -ENODEV; |
420 | ||
421 | switch(req->type) { | |
b02f6695 | 422 | case DEV_PM_QOS_RESUME_LATENCY: |
2d984ad1 | 423 | case DEV_PM_QOS_LATENCY_TOLERANCE: |
e39473d0 RW |
424 | curr_value = req->data.pnode.prio; |
425 | break; | |
36a8015f LC |
426 | case DEV_PM_QOS_MIN_FREQUENCY: |
427 | case DEV_PM_QOS_MAX_FREQUENCY: | |
428 | curr_value = req->data.freq.pnode.prio; | |
429 | break; | |
e39473d0 RW |
430 | case DEV_PM_QOS_FLAGS: |
431 | curr_value = req->data.flr.flags; | |
432 | break; | |
433 | default: | |
434 | return -EINVAL; | |
435 | } | |
436 | ||
96d9d0b5 S |
437 | trace_dev_pm_qos_update_request(dev_name(req->dev), req->type, |
438 | new_value); | |
e39473d0 RW |
439 | if (curr_value != new_value) |
440 | ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value); | |
441 | ||
442 | return ret; | |
443 | } | |
444 | ||
91ff4cb8 JP |
445 | /** |
446 | * dev_pm_qos_update_request - modifies an existing qos request | |
447 | * @req : handle to list element holding a dev_pm_qos request to use | |
448 | * @new_value: defines the qos request | |
449 | * | |
450 | * Updates an existing dev PM qos request along with updating the | |
451 | * target value. | |
452 | * | |
453 | * Attempts are made to make this code callable on hot code paths. | |
454 | * | |
455 | * Returns 1 if the aggregated constraint value has changed, | |
456 | * 0 if the aggregated constraint value has not changed, | |
457 | * -EINVAL in case of wrong parameters, -ENODEV if the device has been | |
458 | * removed from the system | |
436ede89 RW |
459 | * |
460 | * Callers should ensure that the target device is not RPM_SUSPENDED before | |
461 | * using this function for requests of type DEV_PM_QOS_FLAGS. | |
91ff4cb8 | 462 | */ |
e39473d0 | 463 | int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value) |
91ff4cb8 | 464 | { |
e39473d0 | 465 | int ret; |
91ff4cb8 | 466 | |
b81ea1b5 RW |
467 | mutex_lock(&dev_pm_qos_mtx); |
468 | ret = __dev_pm_qos_update_request(req, new_value); | |
469 | mutex_unlock(&dev_pm_qos_mtx); | |
470 | return ret; | |
471 | } | |
472 | EXPORT_SYMBOL_GPL(dev_pm_qos_update_request); | |
473 | ||
474 | static int __dev_pm_qos_remove_request(struct dev_pm_qos_request *req) | |
475 | { | |
37530f2b | 476 | int ret; |
b81ea1b5 | 477 | |
91ff4cb8 JP |
478 | if (!req) /*guard against callers passing in null */ |
479 | return -EINVAL; | |
480 | ||
af4c720e GL |
481 | if (WARN(!dev_pm_qos_request_active(req), |
482 | "%s() called for unknown object\n", __func__)) | |
91ff4cb8 | 483 | return -EINVAL; |
91ff4cb8 | 484 | |
37530f2b RW |
485 | if (IS_ERR_OR_NULL(req->dev->power.qos)) |
486 | return -ENODEV; | |
487 | ||
96d9d0b5 S |
488 | trace_dev_pm_qos_remove_request(dev_name(req->dev), req->type, |
489 | PM_QOS_DEFAULT_VALUE); | |
37530f2b RW |
490 | ret = apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); |
491 | memset(req, 0, sizeof(*req)); | |
91ff4cb8 JP |
492 | return ret; |
493 | } | |
91ff4cb8 JP |
494 | |
495 | /** | |
496 | * dev_pm_qos_remove_request - modifies an existing qos request | |
497 | * @req: handle to request list element | |
498 | * | |
499 | * Will remove pm qos request from the list of constraints and | |
500 | * recompute the current target value. Call this on slow code paths. | |
501 | * | |
502 | * Returns 1 if the aggregated constraint value has changed, | |
503 | * 0 if the aggregated constraint value has not changed, | |
504 | * -EINVAL in case of wrong parameters, -ENODEV if the device has been | |
505 | * removed from the system | |
436ede89 RW |
506 | * |
507 | * Callers should ensure that the target device is not RPM_SUSPENDED before | |
508 | * using this function for requests of type DEV_PM_QOS_FLAGS. | |
91ff4cb8 JP |
509 | */ |
510 | int dev_pm_qos_remove_request(struct dev_pm_qos_request *req) | |
511 | { | |
b81ea1b5 | 512 | int ret; |
91ff4cb8 JP |
513 | |
514 | mutex_lock(&dev_pm_qos_mtx); | |
b81ea1b5 | 515 | ret = __dev_pm_qos_remove_request(req); |
91ff4cb8 JP |
516 | mutex_unlock(&dev_pm_qos_mtx); |
517 | return ret; | |
518 | } | |
519 | EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request); | |
520 | ||
521 | /** | |
522 | * dev_pm_qos_add_notifier - sets notification entry for changes to target value | |
523 | * of per-device PM QoS constraints | |
524 | * | |
525 | * @dev: target device for the constraint | |
526 | * @notifier: notifier block managed by caller. | |
0b07ee94 | 527 | * @type: request type. |
91ff4cb8 JP |
528 | * |
529 | * Will register the notifier into a notification chain that gets called | |
530 | * upon changes to the target value for the device. | |
23e0fc5a RW |
531 | * |
532 | * If the device's constraints object doesn't exist when this routine is called, | |
533 | * it will be created (or error code will be returned if that fails). | |
91ff4cb8 | 534 | */ |
0b07ee94 VK |
535 | int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier, |
536 | enum dev_pm_qos_req_type type) | |
91ff4cb8 | 537 | { |
23e0fc5a | 538 | int ret = 0; |
91ff4cb8 JP |
539 | |
540 | mutex_lock(&dev_pm_qos_mtx); | |
541 | ||
37530f2b RW |
542 | if (IS_ERR(dev->power.qos)) |
543 | ret = -ENODEV; | |
544 | else if (!dev->power.qos) | |
545 | ret = dev_pm_qos_constraints_allocate(dev); | |
23e0fc5a | 546 | |
208637b3 VK |
547 | if (ret) |
548 | goto unlock; | |
549 | ||
550 | switch (type) { | |
551 | case DEV_PM_QOS_RESUME_LATENCY: | |
b02f6695 RW |
552 | ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers, |
553 | notifier); | |
208637b3 | 554 | break; |
36a8015f LC |
555 | case DEV_PM_QOS_MIN_FREQUENCY: |
556 | ret = freq_qos_add_notifier(&dev->power.qos->freq, | |
557 | FREQ_QOS_MIN, notifier); | |
558 | break; | |
559 | case DEV_PM_QOS_MAX_FREQUENCY: | |
560 | ret = freq_qos_add_notifier(&dev->power.qos->freq, | |
561 | FREQ_QOS_MAX, notifier); | |
562 | break; | |
208637b3 VK |
563 | default: |
564 | WARN_ON(1); | |
565 | ret = -EINVAL; | |
566 | } | |
91ff4cb8 | 567 | |
208637b3 | 568 | unlock: |
91ff4cb8 | 569 | mutex_unlock(&dev_pm_qos_mtx); |
23e0fc5a | 570 | return ret; |
91ff4cb8 JP |
571 | } |
572 | EXPORT_SYMBOL_GPL(dev_pm_qos_add_notifier); | |
573 | ||
574 | /** | |
575 | * dev_pm_qos_remove_notifier - deletes notification for changes to target value | |
576 | * of per-device PM QoS constraints | |
577 | * | |
578 | * @dev: target device for the constraint | |
579 | * @notifier: notifier block to be removed. | |
0b07ee94 | 580 | * @type: request type. |
91ff4cb8 JP |
581 | * |
582 | * Will remove the notifier from the notification chain that gets called | |
583 | * upon changes to the target value. | |
584 | */ | |
585 | int dev_pm_qos_remove_notifier(struct device *dev, | |
0b07ee94 VK |
586 | struct notifier_block *notifier, |
587 | enum dev_pm_qos_req_type type) | |
91ff4cb8 | 588 | { |
208637b3 | 589 | int ret = 0; |
0b07ee94 | 590 | |
91ff4cb8 JP |
591 | mutex_lock(&dev_pm_qos_mtx); |
592 | ||
1a9a9152 | 593 | /* Silently return if the constraints object is not present. */ |
208637b3 VK |
594 | if (IS_ERR_OR_NULL(dev->power.qos)) |
595 | goto unlock; | |
91ff4cb8 | 596 | |
208637b3 VK |
597 | switch (type) { |
598 | case DEV_PM_QOS_RESUME_LATENCY: | |
599 | ret = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers, | |
600 | notifier); | |
601 | break; | |
36a8015f LC |
602 | case DEV_PM_QOS_MIN_FREQUENCY: |
603 | ret = freq_qos_remove_notifier(&dev->power.qos->freq, | |
604 | FREQ_QOS_MIN, notifier); | |
605 | break; | |
606 | case DEV_PM_QOS_MAX_FREQUENCY: | |
607 | ret = freq_qos_remove_notifier(&dev->power.qos->freq, | |
608 | FREQ_QOS_MAX, notifier); | |
609 | break; | |
208637b3 VK |
610 | default: |
611 | WARN_ON(1); | |
612 | ret = -EINVAL; | |
613 | } | |
614 | ||
615 | unlock: | |
91ff4cb8 | 616 | mutex_unlock(&dev_pm_qos_mtx); |
208637b3 | 617 | return ret; |
91ff4cb8 JP |
618 | } |
619 | EXPORT_SYMBOL_GPL(dev_pm_qos_remove_notifier); | |
b66213cd | 620 | |
40a5f8be RW |
621 | /** |
622 | * dev_pm_qos_add_ancestor_request - Add PM QoS request for device's ancestor. | |
623 | * @dev: Device whose ancestor to add the request for. | |
624 | * @req: Pointer to the preallocated handle. | |
71d821fd | 625 | * @type: Type of the request. |
40a5f8be RW |
626 | * @value: Constraint latency value. |
627 | */ | |
628 | int dev_pm_qos_add_ancestor_request(struct device *dev, | |
71d821fd RW |
629 | struct dev_pm_qos_request *req, |
630 | enum dev_pm_qos_req_type type, s32 value) | |
40a5f8be RW |
631 | { |
632 | struct device *ancestor = dev->parent; | |
4ce47802 | 633 | int ret = -ENODEV; |
40a5f8be | 634 | |
71d821fd RW |
635 | switch (type) { |
636 | case DEV_PM_QOS_RESUME_LATENCY: | |
637 | while (ancestor && !ancestor->power.ignore_children) | |
638 | ancestor = ancestor->parent; | |
40a5f8be | 639 | |
71d821fd RW |
640 | break; |
641 | case DEV_PM_QOS_LATENCY_TOLERANCE: | |
642 | while (ancestor && !ancestor->power.set_latency_tolerance) | |
643 | ancestor = ancestor->parent; | |
644 | ||
645 | break; | |
646 | default: | |
647 | ancestor = NULL; | |
648 | } | |
40a5f8be | 649 | if (ancestor) |
71d821fd | 650 | ret = dev_pm_qos_add_request(ancestor, req, type, value); |
40a5f8be | 651 | |
4ce47802 | 652 | if (ret < 0) |
40a5f8be RW |
653 | req->dev = NULL; |
654 | ||
4ce47802 | 655 | return ret; |
40a5f8be RW |
656 | } |
657 | EXPORT_SYMBOL_GPL(dev_pm_qos_add_ancestor_request); | |
85dc0b8a | 658 | |
e39473d0 RW |
659 | static void __dev_pm_qos_drop_user_request(struct device *dev, |
660 | enum dev_pm_qos_req_type type) | |
85dc0b8a | 661 | { |
b81ea1b5 RW |
662 | struct dev_pm_qos_request *req = NULL; |
663 | ||
e39473d0 | 664 | switch(type) { |
b02f6695 RW |
665 | case DEV_PM_QOS_RESUME_LATENCY: |
666 | req = dev->power.qos->resume_latency_req; | |
667 | dev->power.qos->resume_latency_req = NULL; | |
e39473d0 | 668 | break; |
2d984ad1 RW |
669 | case DEV_PM_QOS_LATENCY_TOLERANCE: |
670 | req = dev->power.qos->latency_tolerance_req; | |
671 | dev->power.qos->latency_tolerance_req = NULL; | |
672 | break; | |
e39473d0 | 673 | case DEV_PM_QOS_FLAGS: |
b81ea1b5 | 674 | req = dev->power.qos->flags_req; |
e39473d0 RW |
675 | dev->power.qos->flags_req = NULL; |
676 | break; | |
208637b3 VK |
677 | default: |
678 | WARN_ON(1); | |
679 | return; | |
e39473d0 | 680 | } |
b81ea1b5 RW |
681 | __dev_pm_qos_remove_request(req); |
682 | kfree(req); | |
85dc0b8a RW |
683 | } |
684 | ||
0f703069 RW |
685 | static void dev_pm_qos_drop_user_request(struct device *dev, |
686 | enum dev_pm_qos_req_type type) | |
687 | { | |
688 | mutex_lock(&dev_pm_qos_mtx); | |
689 | __dev_pm_qos_drop_user_request(dev, type); | |
690 | mutex_unlock(&dev_pm_qos_mtx); | |
691 | } | |
692 | ||
85dc0b8a RW |
693 | /** |
694 | * dev_pm_qos_expose_latency_limit - Expose PM QoS latency limit to user space. | |
695 | * @dev: Device whose PM QoS latency limit is to be exposed to user space. | |
696 | * @value: Initial value of the latency limit. | |
697 | */ | |
698 | int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) | |
699 | { | |
700 | struct dev_pm_qos_request *req; | |
701 | int ret; | |
702 | ||
703 | if (!device_is_registered(dev) || value < 0) | |
704 | return -EINVAL; | |
705 | ||
85dc0b8a RW |
706 | req = kzalloc(sizeof(*req), GFP_KERNEL); |
707 | if (!req) | |
708 | return -ENOMEM; | |
709 | ||
b02f6695 | 710 | ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_RESUME_LATENCY, value); |
b81ea1b5 RW |
711 | if (ret < 0) { |
712 | kfree(req); | |
85dc0b8a | 713 | return ret; |
b81ea1b5 RW |
714 | } |
715 | ||
0f703069 RW |
716 | mutex_lock(&dev_pm_qos_sysfs_mtx); |
717 | ||
b81ea1b5 RW |
718 | mutex_lock(&dev_pm_qos_mtx); |
719 | ||
37530f2b | 720 | if (IS_ERR_OR_NULL(dev->power.qos)) |
b81ea1b5 | 721 | ret = -ENODEV; |
b02f6695 | 722 | else if (dev->power.qos->resume_latency_req) |
b81ea1b5 RW |
723 | ret = -EEXIST; |
724 | ||
725 | if (ret < 0) { | |
726 | __dev_pm_qos_remove_request(req); | |
727 | kfree(req); | |
0f703069 | 728 | mutex_unlock(&dev_pm_qos_mtx); |
b81ea1b5 RW |
729 | goto out; |
730 | } | |
b02f6695 | 731 | dev->power.qos->resume_latency_req = req; |
0f703069 RW |
732 | |
733 | mutex_unlock(&dev_pm_qos_mtx); | |
734 | ||
b02f6695 | 735 | ret = pm_qos_sysfs_add_resume_latency(dev); |
85dc0b8a | 736 | if (ret) |
b02f6695 | 737 | dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); |
85dc0b8a | 738 | |
b81ea1b5 | 739 | out: |
0f703069 | 740 | mutex_unlock(&dev_pm_qos_sysfs_mtx); |
85dc0b8a RW |
741 | return ret; |
742 | } | |
743 | EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_limit); | |
744 | ||
37530f2b RW |
745 | static void __dev_pm_qos_hide_latency_limit(struct device *dev) |
746 | { | |
b02f6695 RW |
747 | if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->resume_latency_req) |
748 | __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); | |
37530f2b RW |
749 | } |
750 | ||
85dc0b8a RW |
751 | /** |
752 | * dev_pm_qos_hide_latency_limit - Hide PM QoS latency limit from user space. | |
753 | * @dev: Device whose PM QoS latency limit is to be hidden from user space. | |
754 | */ | |
755 | void dev_pm_qos_hide_latency_limit(struct device *dev) | |
756 | { | |
0f703069 RW |
757 | mutex_lock(&dev_pm_qos_sysfs_mtx); |
758 | ||
b02f6695 | 759 | pm_qos_sysfs_remove_resume_latency(dev); |
0f703069 | 760 | |
b81ea1b5 | 761 | mutex_lock(&dev_pm_qos_mtx); |
37530f2b | 762 | __dev_pm_qos_hide_latency_limit(dev); |
b81ea1b5 | 763 | mutex_unlock(&dev_pm_qos_mtx); |
0f703069 RW |
764 | |
765 | mutex_unlock(&dev_pm_qos_sysfs_mtx); | |
85dc0b8a RW |
766 | } |
767 | EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_limit); | |
e39473d0 RW |
768 | |
769 | /** | |
770 | * dev_pm_qos_expose_flags - Expose PM QoS flags of a device to user space. | |
771 | * @dev: Device whose PM QoS flags are to be exposed to user space. | |
772 | * @val: Initial values of the flags. | |
773 | */ | |
774 | int dev_pm_qos_expose_flags(struct device *dev, s32 val) | |
775 | { | |
776 | struct dev_pm_qos_request *req; | |
777 | int ret; | |
778 | ||
779 | if (!device_is_registered(dev)) | |
780 | return -EINVAL; | |
781 | ||
e39473d0 RW |
782 | req = kzalloc(sizeof(*req), GFP_KERNEL); |
783 | if (!req) | |
784 | return -ENOMEM; | |
785 | ||
786 | ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_FLAGS, val); | |
b81ea1b5 RW |
787 | if (ret < 0) { |
788 | kfree(req); | |
789 | return ret; | |
790 | } | |
791 | ||
792 | pm_runtime_get_sync(dev); | |
0f703069 RW |
793 | mutex_lock(&dev_pm_qos_sysfs_mtx); |
794 | ||
b81ea1b5 RW |
795 | mutex_lock(&dev_pm_qos_mtx); |
796 | ||
37530f2b | 797 | if (IS_ERR_OR_NULL(dev->power.qos)) |
b81ea1b5 RW |
798 | ret = -ENODEV; |
799 | else if (dev->power.qos->flags_req) | |
800 | ret = -EEXIST; | |
801 | ||
802 | if (ret < 0) { | |
803 | __dev_pm_qos_remove_request(req); | |
804 | kfree(req); | |
0f703069 | 805 | mutex_unlock(&dev_pm_qos_mtx); |
b81ea1b5 RW |
806 | goto out; |
807 | } | |
e39473d0 | 808 | dev->power.qos->flags_req = req; |
0f703069 RW |
809 | |
810 | mutex_unlock(&dev_pm_qos_mtx); | |
811 | ||
e39473d0 RW |
812 | ret = pm_qos_sysfs_add_flags(dev); |
813 | if (ret) | |
0f703069 | 814 | dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); |
e39473d0 | 815 | |
b81ea1b5 | 816 | out: |
0f703069 | 817 | mutex_unlock(&dev_pm_qos_sysfs_mtx); |
7e4d6844 | 818 | pm_runtime_put(dev); |
e39473d0 RW |
819 | return ret; |
820 | } | |
821 | EXPORT_SYMBOL_GPL(dev_pm_qos_expose_flags); | |
822 | ||
37530f2b RW |
823 | static void __dev_pm_qos_hide_flags(struct device *dev) |
824 | { | |
0f703069 | 825 | if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->flags_req) |
37530f2b | 826 | __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); |
37530f2b RW |
827 | } |
828 | ||
e39473d0 RW |
829 | /** |
830 | * dev_pm_qos_hide_flags - Hide PM QoS flags of a device from user space. | |
831 | * @dev: Device whose PM QoS flags are to be hidden from user space. | |
832 | */ | |
833 | void dev_pm_qos_hide_flags(struct device *dev) | |
834 | { | |
b81ea1b5 | 835 | pm_runtime_get_sync(dev); |
0f703069 RW |
836 | mutex_lock(&dev_pm_qos_sysfs_mtx); |
837 | ||
838 | pm_qos_sysfs_remove_flags(dev); | |
839 | ||
b81ea1b5 | 840 | mutex_lock(&dev_pm_qos_mtx); |
37530f2b | 841 | __dev_pm_qos_hide_flags(dev); |
b81ea1b5 | 842 | mutex_unlock(&dev_pm_qos_mtx); |
0f703069 RW |
843 | |
844 | mutex_unlock(&dev_pm_qos_sysfs_mtx); | |
b81ea1b5 | 845 | pm_runtime_put(dev); |
e39473d0 RW |
846 | } |
847 | EXPORT_SYMBOL_GPL(dev_pm_qos_hide_flags); | |
848 | ||
849 | /** | |
850 | * dev_pm_qos_update_flags - Update PM QoS flags request owned by user space. | |
851 | * @dev: Device to update the PM QoS flags request for. | |
852 | * @mask: Flags to set/clear. | |
853 | * @set: Whether to set or clear the flags (true means set). | |
854 | */ | |
855 | int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set) | |
856 | { | |
857 | s32 value; | |
858 | int ret; | |
859 | ||
e39473d0 RW |
860 | pm_runtime_get_sync(dev); |
861 | mutex_lock(&dev_pm_qos_mtx); | |
862 | ||
37530f2b | 863 | if (IS_ERR_OR_NULL(dev->power.qos) || !dev->power.qos->flags_req) { |
b81ea1b5 RW |
864 | ret = -EINVAL; |
865 | goto out; | |
866 | } | |
867 | ||
e39473d0 RW |
868 | value = dev_pm_qos_requested_flags(dev); |
869 | if (set) | |
870 | value |= mask; | |
871 | else | |
872 | value &= ~mask; | |
873 | ||
874 | ret = __dev_pm_qos_update_request(dev->power.qos->flags_req, value); | |
875 | ||
b81ea1b5 | 876 | out: |
e39473d0 RW |
877 | mutex_unlock(&dev_pm_qos_mtx); |
878 | pm_runtime_put(dev); | |
e39473d0 RW |
879 | return ret; |
880 | } | |
2d984ad1 RW |
881 | |
882 | /** | |
883 | * dev_pm_qos_get_user_latency_tolerance - Get user space latency tolerance. | |
884 | * @dev: Device to obtain the user space latency tolerance for. | |
885 | */ | |
886 | s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev) | |
887 | { | |
888 | s32 ret; | |
889 | ||
890 | mutex_lock(&dev_pm_qos_mtx); | |
891 | ret = IS_ERR_OR_NULL(dev->power.qos) | |
892 | || !dev->power.qos->latency_tolerance_req ? | |
893 | PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT : | |
894 | dev->power.qos->latency_tolerance_req->data.pnode.prio; | |
895 | mutex_unlock(&dev_pm_qos_mtx); | |
896 | return ret; | |
897 | } | |
898 | ||
899 | /** | |
900 | * dev_pm_qos_update_user_latency_tolerance - Update user space latency tolerance. | |
901 | * @dev: Device to update the user space latency tolerance for. | |
902 | * @val: New user space latency tolerance for @dev (negative values disable). | |
903 | */ | |
904 | int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) | |
905 | { | |
906 | int ret; | |
907 | ||
908 | mutex_lock(&dev_pm_qos_mtx); | |
909 | ||
910 | if (IS_ERR_OR_NULL(dev->power.qos) | |
911 | || !dev->power.qos->latency_tolerance_req) { | |
912 | struct dev_pm_qos_request *req; | |
913 | ||
914 | if (val < 0) { | |
80a6f7c7 AL |
915 | if (val == PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT) |
916 | ret = 0; | |
917 | else | |
918 | ret = -EINVAL; | |
2d984ad1 RW |
919 | goto out; |
920 | } | |
921 | req = kzalloc(sizeof(*req), GFP_KERNEL); | |
922 | if (!req) { | |
923 | ret = -ENOMEM; | |
924 | goto out; | |
925 | } | |
926 | ret = __dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY_TOLERANCE, val); | |
927 | if (ret < 0) { | |
928 | kfree(req); | |
929 | goto out; | |
930 | } | |
931 | dev->power.qos->latency_tolerance_req = req; | |
932 | } else { | |
933 | if (val < 0) { | |
934 | __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY_TOLERANCE); | |
935 | ret = 0; | |
936 | } else { | |
937 | ret = __dev_pm_qos_update_request(dev->power.qos->latency_tolerance_req, val); | |
938 | } | |
939 | } | |
940 | ||
941 | out: | |
942 | mutex_unlock(&dev_pm_qos_mtx); | |
943 | return ret; | |
944 | } | |
034e7906 | 945 | EXPORT_SYMBOL_GPL(dev_pm_qos_update_user_latency_tolerance); |
13b2c4a0 MW |
946 | |
947 | /** | |
948 | * dev_pm_qos_expose_latency_tolerance - Expose latency tolerance to userspace | |
949 | * @dev: Device whose latency tolerance to expose | |
950 | */ | |
951 | int dev_pm_qos_expose_latency_tolerance(struct device *dev) | |
952 | { | |
953 | int ret; | |
954 | ||
955 | if (!dev->power.set_latency_tolerance) | |
956 | return -EINVAL; | |
957 | ||
958 | mutex_lock(&dev_pm_qos_sysfs_mtx); | |
959 | ret = pm_qos_sysfs_add_latency_tolerance(dev); | |
960 | mutex_unlock(&dev_pm_qos_sysfs_mtx); | |
961 | ||
962 | return ret; | |
963 | } | |
964 | EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_tolerance); | |
965 | ||
966 | /** | |
967 | * dev_pm_qos_hide_latency_tolerance - Hide latency tolerance from userspace | |
968 | * @dev: Device whose latency tolerance to hide | |
969 | */ | |
970 | void dev_pm_qos_hide_latency_tolerance(struct device *dev) | |
971 | { | |
972 | mutex_lock(&dev_pm_qos_sysfs_mtx); | |
973 | pm_qos_sysfs_remove_latency_tolerance(dev); | |
974 | mutex_unlock(&dev_pm_qos_sysfs_mtx); | |
975 | ||
976 | /* Remove the request from user space now */ | |
977 | pm_runtime_get_sync(dev); | |
978 | dev_pm_qos_update_user_latency_tolerance(dev, | |
979 | PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT); | |
980 | pm_runtime_put(dev); | |
981 | } | |
982 | EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_tolerance); |