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