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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->dedicated_irq)
114 free_irq(wirq->irq, wirq);
115 kfree(wirq);
116}
117EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
118
119/**
120 * handle_threaded_wake_irq - Handler for dedicated wake-up interrupts
121 * @irq: Device specific dedicated wake-up interrupt
122 * @_wirq: Wake IRQ data
123 *
124 * Some devices have a separate wake-up interrupt in addition to the
125 * device IO interrupt. The wake-up interrupt signals that a device
126 * should be woken up from it's idle state. This handler uses device
127 * specific pm_runtime functions to wake the device, and then it's
128 * up to the device to do whatever it needs to. Note that as the
129 * device may need to restore context and start up regulators, we
130 * use a threaded IRQ.
131 *
132 * Also note that we are not resending the lost device interrupts.
133 * We assume that the wake-up interrupt just needs to wake-up the
134 * device, and then device's pm_runtime_resume() can deal with the
135 * situation.
136 */
137static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq)
138{
139 struct wake_irq *wirq = _wirq;
140 int res;
141
142 /* We don't want RPM_ASYNC or RPM_NOWAIT here */
143 res = pm_runtime_resume(wirq->dev);
144 if (res < 0)
145 dev_warn(wirq->dev,
146 "wake IRQ with no resume: %i\n", res);
147
148 return IRQ_HANDLED;
149}
150
151/**
152 * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt
153 * @dev: Device entry
154 * @irq: Device wake-up interrupt
155 *
156 * Unless your hardware has separate wake-up interrupts in addition
157 * to the device IO interrupts, you don't need this.
158 *
159 * Sets up a threaded interrupt handler for a device that has
160 * a dedicated wake-up interrupt in addition to the device IO
161 * interrupt.
162 *
163 * The interrupt starts disabled, and needs to be managed for
164 * the device by the bus code or the device driver using
165 * dev_pm_enable_wake_irq() and dev_pm_disable_wake_irq()
166 * functions.
167 */
168int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
169{
170 struct wake_irq *wirq;
171 int err;
172
173 if (irq < 0)
174 return -EINVAL;
175
176 wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
177 if (!wirq)
178 return -ENOMEM;
179
180 wirq->dev = dev;
181 wirq->irq = irq;
182 wirq->dedicated_irq = true;
183 irq_set_status_flags(irq, IRQ_NOAUTOEN);
184
185 /*
186 * Consumer device may need to power up and restore state
187 * so we use a threaded irq.
188 */
189 err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
190 IRQF_ONESHOT, dev_name(dev), wirq);
191 if (err)
192 goto err_free;
193
194 err = dev_pm_attach_wake_irq(dev, irq, wirq);
195 if (err)
196 goto err_free_irq;
197
198 return err;
199
200err_free_irq:
201 free_irq(irq, wirq);
202err_free:
203 kfree(wirq);
204
205 return err;
206}
207EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq);
208
209/**
210 * dev_pm_enable_wake_irq - Enable device wake-up interrupt
211 * @dev: Device
212 *
213 * Called from the bus code or the device driver for
214 * runtime_suspend() to enable the wake-up interrupt while
215 * the device is running.
216 *
217 * Note that for runtime_suspend()) the wake-up interrupts
218 * should be unconditionally enabled unlike for suspend()
219 * that is conditional.
220 */
221void dev_pm_enable_wake_irq(struct device *dev)
222{
223 struct wake_irq *wirq = dev->power.wakeirq;
224
225 if (wirq && wirq->dedicated_irq)
226 enable_irq(wirq->irq);
227}
228EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq);
229
230/**
231 * dev_pm_disable_wake_irq - Disable device wake-up interrupt
232 * @dev: Device
233 *
234 * Called from the bus code or the device driver for
235 * runtime_resume() to disable the wake-up interrupt while
236 * the device is running.
237 */
238void dev_pm_disable_wake_irq(struct device *dev)
239{
240 struct wake_irq *wirq = dev->power.wakeirq;
241
242 if (wirq && wirq->dedicated_irq)
243 disable_irq_nosync(wirq->irq);
244}
245EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq);
246
247/**
248 * dev_pm_arm_wake_irq - Arm device wake-up
249 * @wirq: Device wake-up interrupt
250 *
251 * Sets up the wake-up event conditionally based on the
252 * device_may_wake().
253 */
254void dev_pm_arm_wake_irq(struct wake_irq *wirq)
255{
256 if (!wirq)
257 return;
258
259 if (device_may_wakeup(wirq->dev))
260 enable_irq_wake(wirq->irq);
261}
262
263/**
264 * dev_pm_disarm_wake_irq - Disarm device wake-up
265 * @wirq: Device wake-up interrupt
266 *
267 * Clears up the wake-up event conditionally based on the
268 * device_may_wake().
269 */
270void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
271{
272 if (!wirq)
273 return;
274
275 if (device_may_wakeup(wirq->dev))
276 disable_irq_wake(wirq->irq);
277}
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 */
19static 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 */
50int 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(sizeof(*wirq), GFP_KERNEL);
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}
71EXPORT_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 */
84void dev_pm_clear_wake_irq(struct device *dev)
85{
86 struct wake_irq *wirq = dev->power.wakeirq;
87 unsigned long flags;
88
89 if (!wirq)
90 return;
91
92 spin_lock_irqsave(&dev->power.lock, flags);
93 device_wakeup_detach_irq(dev);
94 dev->power.wakeirq = NULL;
95 spin_unlock_irqrestore(&dev->power.lock, flags);
96
97 if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) {
98 free_irq(wirq->irq, wirq);
99 wirq->status &= ~WAKE_IRQ_DEDICATED_MASK;
100 }
101 kfree(wirq->name);
102 kfree(wirq);
103}
104EXPORT_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 */
124static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq)
125{
126 struct wake_irq *wirq = _wirq;
127 int res;
128
129 /* Maybe abort suspend? */
130 if (irqd_is_wakeup_set(irq_get_irq_data(irq))) {
131 pm_wakeup_event(wirq->dev, 0);
132
133 return IRQ_HANDLED;
134 }
135
136 /* We don't want RPM_ASYNC or RPM_NOWAIT here */
137 res = pm_runtime_resume(wirq->dev);
138 if (res < 0)
139 dev_warn(wirq->dev,
140 "wake IRQ with no resume: %i\n", res);
141
142 return IRQ_HANDLED;
143}
144
145static 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 if (irq < 0)
151 return -EINVAL;
152
153 wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
154 if (!wirq)
155 return -ENOMEM;
156
157 wirq->name = kasprintf(GFP_KERNEL, "%s:wakeup", dev_name(dev));
158 if (!wirq->name) {
159 err = -ENOMEM;
160 goto err_free;
161 }
162
163 wirq->dev = dev;
164 wirq->irq = irq;
165
166 /* Prevent deferred spurious wakeirqs with disable_irq_nosync() */
167 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 err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
174 IRQF_ONESHOT | IRQF_NO_AUTOEN,
175 wirq->name, wirq);
176 if (err)
177 goto err_free_name;
178
179 err = dev_pm_attach_wake_irq(dev, wirq);
180 if (err)
181 goto err_free_irq;
182
183 wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED | flag;
184
185 return err;
186
187err_free_irq:
188 free_irq(irq, wirq);
189err_free_name:
190 kfree(wirq->name);
191err_free:
192 kfree(wirq);
193
194 return err;
195}
196
197/**
198 * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt
199 * @dev: Device entry
200 * @irq: Device wake-up interrupt
201 *
202 * Unless your hardware has separate wake-up interrupts in addition
203 * to the device IO interrupts, you don't need this.
204 *
205 * Sets up a threaded interrupt handler for a device that has
206 * a dedicated wake-up interrupt in addition to the device IO
207 * interrupt.
208 */
209int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
210{
211 return __dev_pm_set_dedicated_wake_irq(dev, irq, 0);
212}
213EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq);
214
215/**
216 * dev_pm_set_dedicated_wake_irq_reverse - Request a dedicated wake-up interrupt
217 * with reverse enable ordering
218 * @dev: Device entry
219 * @irq: Device wake-up interrupt
220 *
221 * Unless your hardware has separate wake-up interrupts in addition
222 * to the device IO interrupts, you don't need this.
223 *
224 * Sets up a threaded interrupt handler for a device that has a dedicated
225 * wake-up interrupt in addition to the device IO interrupt. It sets
226 * the status of WAKE_IRQ_DEDICATED_REVERSE to tell rpm_suspend()
227 * to enable dedicated wake-up interrupt after running the runtime suspend
228 * callback for @dev.
229 */
230int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq)
231{
232 return __dev_pm_set_dedicated_wake_irq(dev, irq, WAKE_IRQ_DEDICATED_REVERSE);
233}
234EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq_reverse);
235
236/**
237 * dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt
238 * @dev: Device
239 * @can_change_status: Can change wake-up interrupt status
240 *
241 * Enables wakeirq conditionally. We need to enable wake-up interrupt
242 * lazily on the first rpm_suspend(). This is needed as the consumer device
243 * starts in RPM_SUSPENDED state, and the first pm_runtime_get() would
244 * otherwise try to disable already disabled wakeirq. The wake-up interrupt
245 * starts disabled with IRQ_NOAUTOEN set.
246 *
247 * Should be only called from rpm_suspend() and rpm_resume() path.
248 * Caller must hold &dev->power.lock to change wirq->status
249 */
250void dev_pm_enable_wake_irq_check(struct device *dev,
251 bool can_change_status)
252{
253 struct wake_irq *wirq = dev->power.wakeirq;
254
255 if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
256 return;
257
258 if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) {
259 goto enable;
260 } else if (can_change_status) {
261 wirq->status |= WAKE_IRQ_DEDICATED_MANAGED;
262 goto enable;
263 }
264
265 return;
266
267enable:
268 if (!can_change_status || !(wirq->status & WAKE_IRQ_DEDICATED_REVERSE)) {
269 enable_irq(wirq->irq);
270 wirq->status |= WAKE_IRQ_DEDICATED_ENABLED;
271 }
272}
273
274/**
275 * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt
276 * @dev: Device
277 * @cond_disable: if set, also check WAKE_IRQ_DEDICATED_REVERSE
278 *
279 * Disables wake-up interrupt conditionally based on status.
280 * Should be only called from rpm_suspend() and rpm_resume() path.
281 */
282void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable)
283{
284 struct wake_irq *wirq = dev->power.wakeirq;
285
286 if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
287 return;
288
289 if (cond_disable && (wirq->status & WAKE_IRQ_DEDICATED_REVERSE))
290 return;
291
292 if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED) {
293 wirq->status &= ~WAKE_IRQ_DEDICATED_ENABLED;
294 disable_irq_nosync(wirq->irq);
295 }
296}
297
298/**
299 * dev_pm_enable_wake_irq_complete - enable wake IRQ not enabled before
300 * @dev: Device using the wake IRQ
301 *
302 * Enable wake IRQ conditionally based on status, mainly used if want to
303 * enable wake IRQ after running ->runtime_suspend() which depends on
304 * WAKE_IRQ_DEDICATED_REVERSE.
305 *
306 * Should be only called from rpm_suspend() path.
307 */
308void dev_pm_enable_wake_irq_complete(struct device *dev)
309{
310 struct wake_irq *wirq = dev->power.wakeirq;
311
312 if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK))
313 return;
314
315 if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED &&
316 wirq->status & WAKE_IRQ_DEDICATED_REVERSE) {
317 enable_irq(wirq->irq);
318 wirq->status |= WAKE_IRQ_DEDICATED_ENABLED;
319 }
320}
321
322/**
323 * dev_pm_arm_wake_irq - Arm device wake-up
324 * @wirq: Device wake-up interrupt
325 *
326 * Sets up the wake-up event conditionally based on the
327 * device_may_wake().
328 */
329void dev_pm_arm_wake_irq(struct wake_irq *wirq)
330{
331 if (!wirq)
332 return;
333
334 if (device_may_wakeup(wirq->dev)) {
335 if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
336 !(wirq->status & WAKE_IRQ_DEDICATED_ENABLED))
337 enable_irq(wirq->irq);
338
339 enable_irq_wake(wirq->irq);
340 }
341}
342
343/**
344 * dev_pm_disarm_wake_irq - Disarm device wake-up
345 * @wirq: Device wake-up interrupt
346 *
347 * Clears up the wake-up event conditionally based on the
348 * device_may_wake().
349 */
350void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
351{
352 if (!wirq)
353 return;
354
355 if (device_may_wakeup(wirq->dev)) {
356 disable_irq_wake(wirq->irq);
357
358 if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
359 !(wirq->status & WAKE_IRQ_DEDICATED_ENABLED))
360 disable_irq_nosync(wirq->irq);
361 }
362}