Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /* Device wakeirq helper functions */
3 : #include <linux/device.h>
4 : #include <linux/interrupt.h>
5 : #include <linux/irq.h>
6 : #include <linux/slab.h>
7 : #include <linux/pm_runtime.h>
8 : #include <linux/pm_wakeirq.h>
9 :
10 : #include "power.h"
11 :
12 : /**
13 : * dev_pm_attach_wake_irq - Attach device interrupt as a wake IRQ
14 : * @dev: Device entry
15 : * @wirq: Wake irq specific data
16 : *
17 : * Internal function to attach a dedicated wake-up interrupt as a wake IRQ.
18 : */
19 0 : static int dev_pm_attach_wake_irq(struct device *dev, struct wake_irq *wirq)
20 : {
21 : unsigned long flags;
22 :
23 0 : if (!dev || !wirq)
24 : return -EINVAL;
25 :
26 0 : spin_lock_irqsave(&dev->power.lock, flags);
27 0 : if (dev_WARN_ONCE(dev, dev->power.wakeirq,
28 : "wake irq already initialized\n")) {
29 0 : spin_unlock_irqrestore(&dev->power.lock, flags);
30 0 : return -EEXIST;
31 : }
32 :
33 0 : dev->power.wakeirq = wirq;
34 0 : device_wakeup_attach_irq(dev, wirq);
35 :
36 0 : spin_unlock_irqrestore(&dev->power.lock, flags);
37 0 : return 0;
38 : }
39 :
40 : /**
41 : * dev_pm_set_wake_irq - Attach device IO interrupt as wake IRQ
42 : * @dev: Device entry
43 : * @irq: Device IO interrupt
44 : *
45 : * Attach a device IO interrupt as a wake IRQ. The wake IRQ gets
46 : * automatically configured for wake-up from suspend based
47 : * on the device specific sysfs wakeup entry. Typically called
48 : * during driver probe after calling device_init_wakeup().
49 : */
50 0 : int dev_pm_set_wake_irq(struct device *dev, int irq)
51 : {
52 : struct wake_irq *wirq;
53 : int err;
54 :
55 0 : if (irq < 0)
56 : return -EINVAL;
57 :
58 0 : wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
59 0 : if (!wirq)
60 : return -ENOMEM;
61 :
62 0 : wirq->dev = dev;
63 0 : wirq->irq = irq;
64 :
65 0 : err = dev_pm_attach_wake_irq(dev, wirq);
66 0 : if (err)
67 0 : kfree(wirq);
68 :
69 : return err;
70 : }
71 : EXPORT_SYMBOL_GPL(dev_pm_set_wake_irq);
72 :
73 : /**
74 : * dev_pm_clear_wake_irq - Detach a device IO interrupt wake IRQ
75 : * @dev: Device entry
76 : *
77 : * Detach a device wake IRQ and free resources.
78 : *
79 : * Note that it's OK for drivers to call this without calling
80 : * dev_pm_set_wake_irq() as all the driver instances may not have
81 : * a wake IRQ configured. This avoid adding wake IRQ specific
82 : * checks into the drivers.
83 : */
84 0 : void dev_pm_clear_wake_irq(struct device *dev)
85 : {
86 0 : struct wake_irq *wirq = dev->power.wakeirq;
87 : unsigned long flags;
88 :
89 0 : if (!wirq)
90 : return;
91 :
92 0 : spin_lock_irqsave(&dev->power.lock, flags);
93 0 : device_wakeup_detach_irq(dev);
94 0 : dev->power.wakeirq = NULL;
95 0 : spin_unlock_irqrestore(&dev->power.lock, flags);
96 :
97 0 : if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) {
98 0 : free_irq(wirq->irq, wirq);
99 0 : wirq->status &= ~WAKE_IRQ_DEDICATED_MASK;
100 : }
101 0 : kfree(wirq->name);
102 0 : kfree(wirq);
103 : }
104 : EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
105 :
106 : /**
107 : * handle_threaded_wake_irq - Handler for dedicated wake-up interrupts
108 : * @irq: Device specific dedicated wake-up interrupt
109 : * @_wirq: Wake IRQ data
110 : *
111 : * Some devices have a separate wake-up interrupt in addition to the
112 : * device IO interrupt. The wake-up interrupt signals that a device
113 : * should be woken up from it's idle state. This handler uses device
114 : * specific pm_runtime functions to wake the device, and then it's
115 : * up to the device to do whatever it needs to. Note that as the
116 : * device may need to restore context and start up regulators, we
117 : * use a threaded IRQ.
118 : *
119 : * Also note that we are not resending the lost device interrupts.
120 : * We assume that the wake-up interrupt just needs to wake-up the
121 : * device, and then device's pm_runtime_resume() can deal with the
122 : * situation.
123 : */
124 0 : static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq)
125 : {
126 0 : struct wake_irq *wirq = _wirq;
127 : int res;
128 :
129 : /* Maybe abort suspend? */
130 0 : if (irqd_is_wakeup_set(irq_get_irq_data(irq))) {
131 0 : pm_wakeup_event(wirq->dev, 0);
132 :
133 0 : return IRQ_HANDLED;
134 : }
135 :
136 : /* We don't want RPM_ASYNC or RPM_NOWAIT here */
137 0 : res = pm_runtime_resume(wirq->dev);
138 0 : if (res < 0)
139 0 : dev_warn(wirq->dev,
140 : "wake IRQ with no resume: %i\n", res);
141 :
142 : return IRQ_HANDLED;
143 : }
144 :
145 0 : static int __dev_pm_set_dedicated_wake_irq(struct device *dev, int irq, unsigned int flag)
146 : {
147 : struct wake_irq *wirq;
148 : int err;
149 :
150 0 : if (irq < 0)
151 : return -EINVAL;
152 :
153 0 : wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
154 0 : if (!wirq)
155 : return -ENOMEM;
156 :
157 0 : wirq->name = kasprintf(GFP_KERNEL, "%s:wakeup", dev_name(dev));
158 0 : if (!wirq->name) {
159 : err = -ENOMEM;
160 : goto err_free;
161 : }
162 :
163 0 : wirq->dev = dev;
164 0 : wirq->irq = irq;
165 :
166 : /* Prevent deferred spurious wakeirqs with disable_irq_nosync() */
167 0 : irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY);
168 :
169 : /*
170 : * Consumer device may need to power up and restore state
171 : * so we use a threaded irq.
172 : */
173 0 : err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
174 : IRQF_ONESHOT | IRQF_NO_AUTOEN,
175 : wirq->name, wirq);
176 0 : if (err)
177 : goto err_free_name;
178 :
179 0 : err = dev_pm_attach_wake_irq(dev, wirq);
180 0 : if (err)
181 : goto err_free_irq;
182 :
183 0 : wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED | flag;
184 :
185 0 : return err;
186 :
187 : err_free_irq:
188 0 : free_irq(irq, wirq);
189 : err_free_name:
190 0 : kfree(wirq->name);
191 : err_free:
192 0 : kfree(wirq);
193 :
194 0 : return err;
195 : }
196 :
197 :
198 : /**
199 : * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt
200 : * @dev: Device entry
201 : * @irq: Device wake-up interrupt
202 : *
203 : * Unless your hardware has separate wake-up interrupts in addition
204 : * to the device IO interrupts, you don't need this.
205 : *
206 : * Sets up a threaded interrupt handler for a device that has
207 : * a dedicated wake-up interrupt in addition to the device IO
208 : * interrupt.
209 : *
210 : * The interrupt starts disabled, and needs to be managed for
211 : * the device by the bus code or the device driver using
212 : * dev_pm_enable_wake_irq*() and dev_pm_disable_wake_irq*()
213 : * functions.
214 : */
215 0 : int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
216 : {
217 0 : return __dev_pm_set_dedicated_wake_irq(dev, irq, 0);
218 : }
219 : EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq);
220 :
221 : /**
222 : * dev_pm_set_dedicated_wake_irq_reverse - Request a dedicated wake-up interrupt
223 : * with reverse enable ordering
224 : * @dev: Device entry
225 : * @irq: Device wake-up interrupt
226 : *
227 : * Unless your hardware has separate wake-up interrupts in addition
228 : * to the device IO interrupts, you don't need this.
229 : *
230 : * Sets up a threaded interrupt handler for a device that has a dedicated
231 : * wake-up interrupt in addition to the device IO interrupt. It sets
232 : * the status of WAKE_IRQ_DEDICATED_REVERSE to tell rpm_suspend()
233 : * to enable dedicated wake-up interrupt after running the runtime suspend
234 : * callback for @dev.
235 : *
236 : * The interrupt starts disabled, and needs to be managed for
237 : * the device by the bus code or the device driver using
238 : * dev_pm_enable_wake_irq*() and dev_pm_disable_wake_irq*()
239 : * functions.
240 : */
241 0 : int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq)
242 : {
243 0 : return __dev_pm_set_dedicated_wake_irq(dev, irq, WAKE_IRQ_DEDICATED_REVERSE);
244 : }
245 : EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq_reverse);
246 :
247 : /**
248 : * dev_pm_enable_wake_irq - Enable device wake-up interrupt
249 : * @dev: Device
250 : *
251 : * Optionally called from the bus code or the device driver for
252 : * runtime_resume() to override the PM runtime core managed wake-up
253 : * interrupt handling to enable the wake-up interrupt.
254 : *
255 : * Note that for runtime_suspend()) the wake-up interrupts
256 : * should be unconditionally enabled unlike for suspend()
257 : * that is conditional.
258 : */
259 0 : void dev_pm_enable_wake_irq(struct device *dev)
260 : {
261 0 : struct wake_irq *wirq = dev->power.wakeirq;
262 :
263 0 : if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED))
264 0 : enable_irq(wirq->irq);
265 0 : }
266 : EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq);
267 :
268 : /**
269 : * dev_pm_disable_wake_irq - Disable device wake-up interrupt
270 : * @dev: Device
271 : *
272 : * Optionally called from the bus code or the device driver for
273 : * runtime_suspend() to override the PM runtime core managed wake-up
274 : * interrupt handling to disable the wake-up interrupt.
275 : */
276 0 : void dev_pm_disable_wake_irq(struct device *dev)
277 : {
278 0 : struct wake_irq *wirq = dev->power.wakeirq;
279 :
280 0 : if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED))
281 0 : disable_irq_nosync(wirq->irq);
282 0 : }
283 : EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq);
284 :
285 : /**
286 : * dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt
287 : * @dev: Device
288 : * @can_change_status: Can change wake-up interrupt status
289 : *
290 : * Enables wakeirq conditionally. We need to enable wake-up interrupt
291 : * lazily on the first rpm_suspend(). This is needed as the consumer device
292 : * starts in RPM_SUSPENDED state, and the first pm_runtime_get() would
293 : * otherwise try to disable already disabled wakeirq. The wake-up interrupt
294 : * starts disabled with IRQ_NOAUTOEN set.
295 : *
296 : * Should be only called from rpm_suspend() and rpm_resume() path.
297 : * Caller must hold &dev->power.lock to change wirq->status
298 : */
299 0 : void dev_pm_enable_wake_irq_check(struct device *dev,
300 : bool can_change_status)
301 : {
302 0 : struct wake_irq *wirq = dev->power.wakeirq;
303 :
304 0 : if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
305 : return;
306 :
307 0 : if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) {
308 : goto enable;
309 0 : } else if (can_change_status) {
310 0 : wirq->status |= WAKE_IRQ_DEDICATED_MANAGED;
311 0 : goto enable;
312 : }
313 :
314 : return;
315 :
316 : enable:
317 0 : if (!can_change_status || !(wirq->status & WAKE_IRQ_DEDICATED_REVERSE))
318 0 : enable_irq(wirq->irq);
319 : }
320 :
321 : /**
322 : * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt
323 : * @dev: Device
324 : * @cond_disable: if set, also check WAKE_IRQ_DEDICATED_REVERSE
325 : *
326 : * Disables wake-up interrupt conditionally based on status.
327 : * Should be only called from rpm_suspend() and rpm_resume() path.
328 : */
329 0 : void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable)
330 : {
331 0 : struct wake_irq *wirq = dev->power.wakeirq;
332 :
333 0 : if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
334 : return;
335 :
336 0 : if (cond_disable && (wirq->status & WAKE_IRQ_DEDICATED_REVERSE))
337 : return;
338 :
339 0 : if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED)
340 0 : disable_irq_nosync(wirq->irq);
341 : }
342 :
343 : /**
344 : * dev_pm_enable_wake_irq_complete - enable wake IRQ not enabled before
345 : * @dev: Device using the wake IRQ
346 : *
347 : * Enable wake IRQ conditionally based on status, mainly used if want to
348 : * enable wake IRQ after running ->runtime_suspend() which depends on
349 : * WAKE_IRQ_DEDICATED_REVERSE.
350 : *
351 : * Should be only called from rpm_suspend() path.
352 : */
353 0 : void dev_pm_enable_wake_irq_complete(struct device *dev)
354 : {
355 0 : struct wake_irq *wirq = dev->power.wakeirq;
356 :
357 0 : if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
358 : return;
359 :
360 0 : if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED &&
361 : wirq->status & WAKE_IRQ_DEDICATED_REVERSE)
362 0 : enable_irq(wirq->irq);
363 : }
364 :
365 : /**
366 : * dev_pm_arm_wake_irq - Arm device wake-up
367 : * @wirq: Device wake-up interrupt
368 : *
369 : * Sets up the wake-up event conditionally based on the
370 : * device_may_wake().
371 : */
372 0 : void dev_pm_arm_wake_irq(struct wake_irq *wirq)
373 : {
374 0 : if (!wirq)
375 : return;
376 :
377 0 : if (device_may_wakeup(wirq->dev)) {
378 0 : if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
379 0 : !pm_runtime_status_suspended(wirq->dev))
380 0 : enable_irq(wirq->irq);
381 :
382 0 : enable_irq_wake(wirq->irq);
383 : }
384 : }
385 :
386 : /**
387 : * dev_pm_disarm_wake_irq - Disarm device wake-up
388 : * @wirq: Device wake-up interrupt
389 : *
390 : * Clears up the wake-up event conditionally based on the
391 : * device_may_wake().
392 : */
393 0 : void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
394 : {
395 0 : if (!wirq)
396 : return;
397 :
398 0 : if (device_may_wakeup(wirq->dev)) {
399 0 : disable_irq_wake(wirq->irq);
400 :
401 0 : if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
402 0 : !pm_runtime_status_suspended(wirq->dev))
403 0 : disable_irq_nosync(wirq->irq);
404 : }
405 : }
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