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4990d4fe TL |
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 | */ | |
32 | static 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 | ||
4990d4fe | 48 | err = device_wakeup_attach_irq(dev, wirq); |
6d3dab7d RW |
49 | if (!err) |
50 | dev->power.wakeirq = wirq; | |
4990d4fe | 51 | |
6d3dab7d RW |
52 | spin_unlock_irqrestore(&dev->power.lock, flags); |
53 | return err; | |
4990d4fe TL |
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 | */ | |
66 | int dev_pm_set_wake_irq(struct device *dev, int irq) | |
67 | { | |
68 | struct wake_irq *wirq; | |
69 | int err; | |
70 | ||
6f9b36cd DT |
71 | if (irq < 0) |
72 | return -EINVAL; | |
73 | ||
4990d4fe TL |
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 | } | |
87 | EXPORT_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 | */ | |
100 | void 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); | |
6d3dab7d | 109 | device_wakeup_detach_irq(dev); |
4990d4fe TL |
110 | dev->power.wakeirq = NULL; |
111 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
112 | ||
bed57030 | 113 | if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) { |
4990d4fe | 114 | free_irq(wirq->irq, wirq); |
bed57030 TL |
115 | wirq->status &= ~WAKE_IRQ_DEDICATED_MASK; |
116 | } | |
4990d4fe TL |
117 | kfree(wirq); |
118 | } | |
119 | EXPORT_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 | */ | |
139 | static 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 | */ | |
170 | int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) | |
171 | { | |
172 | struct wake_irq *wirq; | |
173 | int err; | |
174 | ||
6f9b36cd DT |
175 | if (irq < 0) |
176 | return -EINVAL; | |
177 | ||
4990d4fe TL |
178 | wirq = kzalloc(sizeof(*wirq), GFP_KERNEL); |
179 | if (!wirq) | |
180 | return -ENOMEM; | |
181 | ||
182 | wirq->dev = dev; | |
183 | wirq->irq = irq; | |
4990d4fe TL |
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 | ||
bed57030 TL |
199 | wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED; |
200 | ||
4990d4fe TL |
201 | return err; |
202 | ||
203 | err_free_irq: | |
204 | free_irq(irq, wirq); | |
205 | err_free: | |
206 | kfree(wirq); | |
207 | ||
208 | return err; | |
209 | } | |
210 | EXPORT_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 | * | |
bed57030 TL |
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. | |
4990d4fe TL |
219 | * |
220 | * Note that for runtime_suspend()) the wake-up interrupts | |
221 | * should be unconditionally enabled unlike for suspend() | |
222 | * that is conditional. | |
223 | */ | |
224 | void dev_pm_enable_wake_irq(struct device *dev) | |
225 | { | |
226 | struct wake_irq *wirq = dev->power.wakeirq; | |
227 | ||
bed57030 | 228 | if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)) |
4990d4fe TL |
229 | enable_irq(wirq->irq); |
230 | } | |
231 | EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq); | |
232 | ||
233 | /** | |
234 | * dev_pm_disable_wake_irq - Disable device wake-up interrupt | |
235 | * @dev: Device | |
236 | * | |
bed57030 TL |
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. | |
4990d4fe TL |
240 | */ |
241 | void dev_pm_disable_wake_irq(struct device *dev) | |
242 | { | |
243 | struct wake_irq *wirq = dev->power.wakeirq; | |
244 | ||
bed57030 | 245 | if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)) |
4990d4fe TL |
246 | disable_irq_nosync(wirq->irq); |
247 | } | |
248 | EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq); | |
249 | ||
bed57030 TL |
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 | */ | |
264 | void 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 | ||
281 | enable: | |
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 | */ | |
292 | void 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 | ||
4990d4fe TL |
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 | */ | |
310 | void 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 | */ | |
326 | void 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 | } |