2 * wakeirq.c - Device wakeirq helper functions
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.
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.
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>
24 * dev_pm_attach_wake_irq - Attach device interrupt as a wake IRQ
26 * @irq: Device wake-up capable interrupt
27 * @wirq: Wake irq specific data
29 * Internal function to attach either a device IO interrupt or a
30 * dedicated wake-up interrupt as a wake IRQ.
32 static int dev_pm_attach_wake_irq(struct device *dev, int irq,
33 struct wake_irq *wirq)
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);
48 err = device_wakeup_attach_irq(dev, wirq);
50 dev->power.wakeirq = wirq;
52 spin_unlock_irqrestore(&dev->power.lock, flags);
57 * dev_pm_set_wake_irq - Attach device IO interrupt as wake IRQ
59 * @irq: Device IO interrupt
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().
66 int dev_pm_set_wake_irq(struct device *dev, int irq)
68 struct wake_irq *wirq;
74 wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
81 err = dev_pm_attach_wake_irq(dev, irq, wirq);
87 EXPORT_SYMBOL_GPL(dev_pm_set_wake_irq);
90 * dev_pm_clear_wake_irq - Detach a device IO interrupt wake IRQ
93 * Detach a device wake IRQ and free resources.
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.
100 void dev_pm_clear_wake_irq(struct device *dev)
102 struct wake_irq *wirq = dev->power.wakeirq;
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);
113 if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) {
114 free_irq(wirq->irq, wirq);
115 wirq->status &= ~WAKE_IRQ_DEDICATED_MASK;
119 EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
122 * handle_threaded_wake_irq - Handler for dedicated wake-up interrupts
123 * @irq: Device specific dedicated wake-up interrupt
124 * @_wirq: Wake IRQ data
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.
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
139 static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq)
141 struct wake_irq *wirq = _wirq;
144 /* We don't want RPM_ASYNC or RPM_NOWAIT here */
145 res = pm_runtime_resume(wirq->dev);
148 "wake IRQ with no resume: %i\n", res);
154 * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt
156 * @irq: Device wake-up interrupt
158 * Unless your hardware has separate wake-up interrupts in addition
159 * to the device IO interrupts, you don't need this.
161 * Sets up a threaded interrupt handler for a device that has
162 * a dedicated wake-up interrupt in addition to the device IO
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()
170 int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
172 struct wake_irq *wirq;
178 wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
184 irq_set_status_flags(irq, IRQ_NOAUTOEN);
186 /* Prevent deferred spurious wakeirqs with disable_irq_nosync() */
187 irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY);
190 * Consumer device may need to power up and restore state
191 * so we use a threaded irq.
193 err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
194 IRQF_ONESHOT, dev_name(dev), wirq);
198 err = dev_pm_attach_wake_irq(dev, irq, wirq);
202 wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED;
213 EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq);
216 * dev_pm_enable_wake_irq - Enable device wake-up interrupt
219 * Optionally called from the bus code or the device driver for
220 * runtime_resume() to override the PM runtime core managed wake-up
221 * interrupt handling to enable the wake-up interrupt.
223 * Note that for runtime_suspend()) the wake-up interrupts
224 * should be unconditionally enabled unlike for suspend()
225 * that is conditional.
227 void dev_pm_enable_wake_irq(struct device *dev)
229 struct wake_irq *wirq = dev->power.wakeirq;
231 if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED))
232 enable_irq(wirq->irq);
234 EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq);
237 * dev_pm_disable_wake_irq - Disable device wake-up interrupt
240 * Optionally called from the bus code or the device driver for
241 * runtime_suspend() to override the PM runtime core managed wake-up
242 * interrupt handling to disable the wake-up interrupt.
244 void dev_pm_disable_wake_irq(struct device *dev)
246 struct wake_irq *wirq = dev->power.wakeirq;
248 if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED))
249 disable_irq_nosync(wirq->irq);
251 EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq);
254 * dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt
256 * @can_change_status: Can change wake-up interrupt status
258 * Enables wakeirq conditionally. We need to enable wake-up interrupt
259 * lazily on the first rpm_suspend(). This is needed as the consumer device
260 * starts in RPM_SUSPENDED state, and the the first pm_runtime_get() would
261 * otherwise try to disable already disabled wakeirq. The wake-up interrupt
262 * starts disabled with IRQ_NOAUTOEN set.
264 * Should be only called from rpm_suspend() and rpm_resume() path.
265 * Caller must hold &dev->power.lock to change wirq->status
267 void dev_pm_enable_wake_irq_check(struct device *dev,
268 bool can_change_status)
270 struct wake_irq *wirq = dev->power.wakeirq;
272 if (!wirq || !((wirq->status & WAKE_IRQ_DEDICATED_MASK)))
275 if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) {
277 } else if (can_change_status) {
278 wirq->status |= WAKE_IRQ_DEDICATED_MANAGED;
285 enable_irq(wirq->irq);
289 * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt
292 * Disables wake-up interrupt conditionally based on status.
293 * Should be only called from rpm_suspend() and rpm_resume() path.
295 void dev_pm_disable_wake_irq_check(struct device *dev)
297 struct wake_irq *wirq = dev->power.wakeirq;
299 if (!wirq || !((wirq->status & WAKE_IRQ_DEDICATED_MASK)))
302 if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED)
303 disable_irq_nosync(wirq->irq);
307 * dev_pm_arm_wake_irq - Arm device wake-up
308 * @wirq: Device wake-up interrupt
310 * Sets up the wake-up event conditionally based on the
313 void dev_pm_arm_wake_irq(struct wake_irq *wirq)
318 if (device_may_wakeup(wirq->dev)) {
319 if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)
320 enable_irq(wirq->irq);
322 enable_irq_wake(wirq->irq);
327 * dev_pm_disarm_wake_irq - Disarm device wake-up
328 * @wirq: Device wake-up interrupt
330 * Clears up the wake-up event conditionally based on the
333 void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
338 if (device_may_wakeup(wirq->dev)) {
339 disable_irq_wake(wirq->irq);
341 if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)
342 disable_irq_nosync(wirq->irq);