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