]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/irq/manage.c | |
3 | * | |
a34db9b2 IM |
4 | * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar |
5 | * Copyright (C) 2005-2006 Thomas Gleixner | |
1da177e4 LT |
6 | * |
7 | * This file contains driver APIs to the irq subsystem. | |
8 | */ | |
9 | ||
10 | #include <linux/irq.h> | |
3aa551c9 | 11 | #include <linux/kthread.h> |
1da177e4 LT |
12 | #include <linux/module.h> |
13 | #include <linux/random.h> | |
14 | #include <linux/interrupt.h> | |
1aeb272c | 15 | #include <linux/slab.h> |
3aa551c9 | 16 | #include <linux/sched.h> |
1da177e4 LT |
17 | |
18 | #include "internals.h" | |
19 | ||
1da177e4 LT |
20 | /** |
21 | * synchronize_irq - wait for pending IRQ handlers (on other CPUs) | |
1e5d5331 | 22 | * @irq: interrupt number to wait for |
1da177e4 LT |
23 | * |
24 | * This function waits for any pending IRQ handlers for this interrupt | |
25 | * to complete before returning. If you use this function while | |
26 | * holding a resource the IRQ handler may need you will deadlock. | |
27 | * | |
28 | * This function may be called - with care - from IRQ context. | |
29 | */ | |
30 | void synchronize_irq(unsigned int irq) | |
31 | { | |
cb5bc832 | 32 | struct irq_desc *desc = irq_to_desc(irq); |
a98ce5c6 | 33 | unsigned int status; |
1da177e4 | 34 | |
7d94f7ca | 35 | if (!desc) |
c2b5a251 MW |
36 | return; |
37 | ||
a98ce5c6 HX |
38 | do { |
39 | unsigned long flags; | |
40 | ||
41 | /* | |
42 | * Wait until we're out of the critical section. This might | |
43 | * give the wrong answer due to the lack of memory barriers. | |
44 | */ | |
45 | while (desc->status & IRQ_INPROGRESS) | |
46 | cpu_relax(); | |
47 | ||
48 | /* Ok, that indicated we're done: double-check carefully. */ | |
239007b8 | 49 | raw_spin_lock_irqsave(&desc->lock, flags); |
a98ce5c6 | 50 | status = desc->status; |
239007b8 | 51 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
a98ce5c6 HX |
52 | |
53 | /* Oops, that failed? */ | |
54 | } while (status & IRQ_INPROGRESS); | |
3aa551c9 TG |
55 | |
56 | /* | |
57 | * We made sure that no hardirq handler is running. Now verify | |
58 | * that no threaded handlers are active. | |
59 | */ | |
60 | wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active)); | |
1da177e4 | 61 | } |
1da177e4 LT |
62 | EXPORT_SYMBOL(synchronize_irq); |
63 | ||
3aa551c9 TG |
64 | #ifdef CONFIG_SMP |
65 | cpumask_var_t irq_default_affinity; | |
66 | ||
771ee3b0 TG |
67 | /** |
68 | * irq_can_set_affinity - Check if the affinity of a given irq can be set | |
69 | * @irq: Interrupt to check | |
70 | * | |
71 | */ | |
72 | int irq_can_set_affinity(unsigned int irq) | |
73 | { | |
08678b08 | 74 | struct irq_desc *desc = irq_to_desc(irq); |
771ee3b0 | 75 | |
6b8ff312 | 76 | if (CHECK_IRQ_PER_CPU(desc->status) || !desc->irq_data.chip || |
c96b3b3c | 77 | !desc->irq_data.chip->irq_set_affinity) |
771ee3b0 TG |
78 | return 0; |
79 | ||
80 | return 1; | |
81 | } | |
82 | ||
591d2fb0 TG |
83 | /** |
84 | * irq_set_thread_affinity - Notify irq threads to adjust affinity | |
85 | * @desc: irq descriptor which has affitnity changed | |
86 | * | |
87 | * We just set IRQTF_AFFINITY and delegate the affinity setting | |
88 | * to the interrupt thread itself. We can not call | |
89 | * set_cpus_allowed_ptr() here as we hold desc->lock and this | |
90 | * code can be called from hard interrupt context. | |
91 | */ | |
92 | void irq_set_thread_affinity(struct irq_desc *desc) | |
3aa551c9 TG |
93 | { |
94 | struct irqaction *action = desc->action; | |
95 | ||
96 | while (action) { | |
97 | if (action->thread) | |
591d2fb0 | 98 | set_bit(IRQTF_AFFINITY, &action->thread_flags); |
3aa551c9 TG |
99 | action = action->next; |
100 | } | |
101 | } | |
102 | ||
771ee3b0 TG |
103 | /** |
104 | * irq_set_affinity - Set the irq affinity of a given irq | |
105 | * @irq: Interrupt to set affinity | |
106 | * @cpumask: cpumask | |
107 | * | |
108 | */ | |
0de26520 | 109 | int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask) |
771ee3b0 | 110 | { |
08678b08 | 111 | struct irq_desc *desc = irq_to_desc(irq); |
c96b3b3c | 112 | struct irq_chip *chip = desc->irq_data.chip; |
f6d87f4b | 113 | unsigned long flags; |
771ee3b0 | 114 | |
c96b3b3c | 115 | if (!chip->irq_set_affinity) |
771ee3b0 TG |
116 | return -EINVAL; |
117 | ||
239007b8 | 118 | raw_spin_lock_irqsave(&desc->lock, flags); |
f6d87f4b | 119 | |
771ee3b0 | 120 | #ifdef CONFIG_GENERIC_PENDING_IRQ |
57b150cc | 121 | if (desc->status & IRQ_MOVE_PCNTXT) { |
c96b3b3c | 122 | if (!chip->irq_set_affinity(&desc->irq_data, cpumask, false)) { |
6b8ff312 | 123 | cpumask_copy(desc->irq_data.affinity, cpumask); |
591d2fb0 | 124 | irq_set_thread_affinity(desc); |
57b150cc YL |
125 | } |
126 | } | |
6ec3cfec | 127 | else { |
f6d87f4b | 128 | desc->status |= IRQ_MOVE_PENDING; |
7f7ace0c | 129 | cpumask_copy(desc->pending_mask, cpumask); |
f6d87f4b | 130 | } |
771ee3b0 | 131 | #else |
c96b3b3c | 132 | if (!chip->irq_set_affinity(&desc->irq_data, cpumask, false)) { |
6b8ff312 | 133 | cpumask_copy(desc->irq_data.affinity, cpumask); |
591d2fb0 | 134 | irq_set_thread_affinity(desc); |
57b150cc | 135 | } |
771ee3b0 | 136 | #endif |
cd7eab44 BH |
137 | if (desc->affinity_notify) { |
138 | kref_get(&desc->affinity_notify->kref); | |
139 | schedule_work(&desc->affinity_notify->work); | |
140 | } | |
f6d87f4b | 141 | desc->status |= IRQ_AFFINITY_SET; |
239007b8 | 142 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
771ee3b0 TG |
143 | return 0; |
144 | } | |
145 | ||
e7a297b0 PWJ |
146 | int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m) |
147 | { | |
148 | struct irq_desc *desc = irq_to_desc(irq); | |
149 | unsigned long flags; | |
150 | ||
151 | if (!desc) | |
152 | return -EINVAL; | |
153 | ||
154 | raw_spin_lock_irqsave(&desc->lock, flags); | |
155 | desc->affinity_hint = m; | |
156 | raw_spin_unlock_irqrestore(&desc->lock, flags); | |
157 | ||
158 | return 0; | |
159 | } | |
160 | EXPORT_SYMBOL_GPL(irq_set_affinity_hint); | |
161 | ||
cd7eab44 BH |
162 | static void irq_affinity_notify(struct work_struct *work) |
163 | { | |
164 | struct irq_affinity_notify *notify = | |
165 | container_of(work, struct irq_affinity_notify, work); | |
166 | struct irq_desc *desc = irq_to_desc(notify->irq); | |
167 | cpumask_var_t cpumask; | |
168 | unsigned long flags; | |
169 | ||
170 | if (!desc) | |
171 | goto out; | |
172 | ||
173 | if (!alloc_cpumask_var(&cpumask, GFP_KERNEL)) | |
174 | goto out; | |
175 | ||
176 | raw_spin_lock_irqsave(&desc->lock, flags); | |
177 | #ifdef CONFIG_GENERIC_PENDING_IRQ | |
178 | if (desc->status & IRQ_MOVE_PENDING) | |
179 | cpumask_copy(cpumask, desc->pending_mask); | |
180 | else | |
181 | #endif | |
1fb0ef31 | 182 | cpumask_copy(cpumask, desc->irq_data.affinity); |
cd7eab44 BH |
183 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
184 | ||
185 | notify->notify(notify, cpumask); | |
186 | ||
187 | free_cpumask_var(cpumask); | |
188 | out: | |
189 | kref_put(¬ify->kref, notify->release); | |
190 | } | |
191 | ||
192 | /** | |
193 | * irq_set_affinity_notifier - control notification of IRQ affinity changes | |
194 | * @irq: Interrupt for which to enable/disable notification | |
195 | * @notify: Context for notification, or %NULL to disable | |
196 | * notification. Function pointers must be initialised; | |
197 | * the other fields will be initialised by this function. | |
198 | * | |
199 | * Must be called in process context. Notification may only be enabled | |
200 | * after the IRQ is allocated and must be disabled before the IRQ is | |
201 | * freed using free_irq(). | |
202 | */ | |
203 | int | |
204 | irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) | |
205 | { | |
206 | struct irq_desc *desc = irq_to_desc(irq); | |
207 | struct irq_affinity_notify *old_notify; | |
208 | unsigned long flags; | |
209 | ||
210 | /* The release function is promised process context */ | |
211 | might_sleep(); | |
212 | ||
213 | if (!desc) | |
214 | return -EINVAL; | |
215 | ||
216 | /* Complete initialisation of *notify */ | |
217 | if (notify) { | |
218 | notify->irq = irq; | |
219 | kref_init(¬ify->kref); | |
220 | INIT_WORK(¬ify->work, irq_affinity_notify); | |
221 | } | |
222 | ||
223 | raw_spin_lock_irqsave(&desc->lock, flags); | |
224 | old_notify = desc->affinity_notify; | |
225 | desc->affinity_notify = notify; | |
226 | raw_spin_unlock_irqrestore(&desc->lock, flags); | |
227 | ||
228 | if (old_notify) | |
229 | kref_put(&old_notify->kref, old_notify->release); | |
230 | ||
231 | return 0; | |
232 | } | |
233 | EXPORT_SYMBOL_GPL(irq_set_affinity_notifier); | |
234 | ||
18404756 MK |
235 | #ifndef CONFIG_AUTO_IRQ_AFFINITY |
236 | /* | |
237 | * Generic version of the affinity autoselector. | |
238 | */ | |
548c8933 | 239 | static int setup_affinity(unsigned int irq, struct irq_desc *desc) |
18404756 | 240 | { |
18404756 MK |
241 | if (!irq_can_set_affinity(irq)) |
242 | return 0; | |
243 | ||
f6d87f4b TG |
244 | /* |
245 | * Preserve an userspace affinity setup, but make sure that | |
246 | * one of the targets is online. | |
247 | */ | |
612e3684 | 248 | if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) { |
6b8ff312 | 249 | if (cpumask_any_and(desc->irq_data.affinity, cpu_online_mask) |
0de26520 RR |
250 | < nr_cpu_ids) |
251 | goto set_affinity; | |
f6d87f4b TG |
252 | else |
253 | desc->status &= ~IRQ_AFFINITY_SET; | |
254 | } | |
255 | ||
6b8ff312 | 256 | cpumask_and(desc->irq_data.affinity, cpu_online_mask, irq_default_affinity); |
0de26520 | 257 | set_affinity: |
c96b3b3c | 258 | desc->irq_data.chip->irq_set_affinity(&desc->irq_data, desc->irq_data.affinity, false); |
18404756 | 259 | |
18404756 MK |
260 | return 0; |
261 | } | |
f6d87f4b | 262 | #else |
548c8933 | 263 | static inline int setup_affinity(unsigned int irq, struct irq_desc *d) |
f6d87f4b TG |
264 | { |
265 | return irq_select_affinity(irq); | |
266 | } | |
18404756 MK |
267 | #endif |
268 | ||
f6d87f4b TG |
269 | /* |
270 | * Called when affinity is set via /proc/irq | |
271 | */ | |
272 | int irq_select_affinity_usr(unsigned int irq) | |
273 | { | |
274 | struct irq_desc *desc = irq_to_desc(irq); | |
275 | unsigned long flags; | |
276 | int ret; | |
277 | ||
239007b8 | 278 | raw_spin_lock_irqsave(&desc->lock, flags); |
548c8933 | 279 | ret = setup_affinity(irq, desc); |
3aa551c9 | 280 | if (!ret) |
591d2fb0 | 281 | irq_set_thread_affinity(desc); |
239007b8 | 282 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
f6d87f4b TG |
283 | |
284 | return ret; | |
285 | } | |
286 | ||
287 | #else | |
548c8933 | 288 | static inline int setup_affinity(unsigned int irq, struct irq_desc *desc) |
f6d87f4b TG |
289 | { |
290 | return 0; | |
291 | } | |
1da177e4 LT |
292 | #endif |
293 | ||
0a0c5168 RW |
294 | void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend) |
295 | { | |
296 | if (suspend) { | |
685fd0b4 | 297 | if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND)) |
0a0c5168 RW |
298 | return; |
299 | desc->status |= IRQ_SUSPENDED; | |
300 | } | |
301 | ||
302 | if (!desc->depth++) { | |
303 | desc->status |= IRQ_DISABLED; | |
bc310dda | 304 | desc->irq_data.chip->irq_disable(&desc->irq_data); |
0a0c5168 RW |
305 | } |
306 | } | |
307 | ||
1da177e4 LT |
308 | /** |
309 | * disable_irq_nosync - disable an irq without waiting | |
310 | * @irq: Interrupt to disable | |
311 | * | |
312 | * Disable the selected interrupt line. Disables and Enables are | |
313 | * nested. | |
314 | * Unlike disable_irq(), this function does not ensure existing | |
315 | * instances of the IRQ handler have completed before returning. | |
316 | * | |
317 | * This function may be called from IRQ context. | |
318 | */ | |
319 | void disable_irq_nosync(unsigned int irq) | |
320 | { | |
d3c60047 | 321 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 LT |
322 | unsigned long flags; |
323 | ||
7d94f7ca | 324 | if (!desc) |
c2b5a251 MW |
325 | return; |
326 | ||
3876ec9e | 327 | chip_bus_lock(desc); |
239007b8 | 328 | raw_spin_lock_irqsave(&desc->lock, flags); |
0a0c5168 | 329 | __disable_irq(desc, irq, false); |
239007b8 | 330 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
3876ec9e | 331 | chip_bus_sync_unlock(desc); |
1da177e4 | 332 | } |
1da177e4 LT |
333 | EXPORT_SYMBOL(disable_irq_nosync); |
334 | ||
335 | /** | |
336 | * disable_irq - disable an irq and wait for completion | |
337 | * @irq: Interrupt to disable | |
338 | * | |
339 | * Disable the selected interrupt line. Enables and Disables are | |
340 | * nested. | |
341 | * This function waits for any pending IRQ handlers for this interrupt | |
342 | * to complete before returning. If you use this function while | |
343 | * holding a resource the IRQ handler may need you will deadlock. | |
344 | * | |
345 | * This function may be called - with care - from IRQ context. | |
346 | */ | |
347 | void disable_irq(unsigned int irq) | |
348 | { | |
d3c60047 | 349 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 | 350 | |
7d94f7ca | 351 | if (!desc) |
c2b5a251 MW |
352 | return; |
353 | ||
1da177e4 LT |
354 | disable_irq_nosync(irq); |
355 | if (desc->action) | |
356 | synchronize_irq(irq); | |
357 | } | |
1da177e4 LT |
358 | EXPORT_SYMBOL(disable_irq); |
359 | ||
0a0c5168 | 360 | void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) |
1adb0850 | 361 | { |
dc5f219e TG |
362 | if (resume) { |
363 | if (!(desc->status & IRQ_SUSPENDED)) { | |
364 | if (!desc->action) | |
365 | return; | |
366 | if (!(desc->action->flags & IRQF_FORCE_RESUME)) | |
367 | return; | |
368 | /* Pretend that it got disabled ! */ | |
369 | desc->depth++; | |
370 | } | |
0a0c5168 | 371 | desc->status &= ~IRQ_SUSPENDED; |
dc5f219e | 372 | } |
0a0c5168 | 373 | |
1adb0850 TG |
374 | switch (desc->depth) { |
375 | case 0: | |
0a0c5168 | 376 | err_out: |
b8c512f6 | 377 | WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq); |
1adb0850 TG |
378 | break; |
379 | case 1: { | |
380 | unsigned int status = desc->status & ~IRQ_DISABLED; | |
381 | ||
0a0c5168 RW |
382 | if (desc->status & IRQ_SUSPENDED) |
383 | goto err_out; | |
1adb0850 TG |
384 | /* Prevent probing on this irq: */ |
385 | desc->status = status | IRQ_NOPROBE; | |
386 | check_irq_resend(desc, irq); | |
387 | /* fall-through */ | |
388 | } | |
389 | default: | |
390 | desc->depth--; | |
391 | } | |
392 | } | |
393 | ||
1da177e4 LT |
394 | /** |
395 | * enable_irq - enable handling of an irq | |
396 | * @irq: Interrupt to enable | |
397 | * | |
398 | * Undoes the effect of one call to disable_irq(). If this | |
399 | * matches the last disable, processing of interrupts on this | |
400 | * IRQ line is re-enabled. | |
401 | * | |
70aedd24 | 402 | * This function may be called from IRQ context only when |
6b8ff312 | 403 | * desc->irq_data.chip->bus_lock and desc->chip->bus_sync_unlock are NULL ! |
1da177e4 LT |
404 | */ |
405 | void enable_irq(unsigned int irq) | |
406 | { | |
d3c60047 | 407 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 LT |
408 | unsigned long flags; |
409 | ||
7d94f7ca | 410 | if (!desc) |
c2b5a251 MW |
411 | return; |
412 | ||
2656c366 TG |
413 | if (WARN(!desc->irq_data.chip || !desc->irq_data.chip->irq_enable, |
414 | KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq)) | |
415 | return; | |
416 | ||
3876ec9e | 417 | chip_bus_lock(desc); |
239007b8 | 418 | raw_spin_lock_irqsave(&desc->lock, flags); |
0a0c5168 | 419 | __enable_irq(desc, irq, false); |
239007b8 | 420 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
3876ec9e | 421 | chip_bus_sync_unlock(desc); |
1da177e4 | 422 | } |
1da177e4 LT |
423 | EXPORT_SYMBOL(enable_irq); |
424 | ||
0c5d1eb7 | 425 | static int set_irq_wake_real(unsigned int irq, unsigned int on) |
2db87321 | 426 | { |
08678b08 | 427 | struct irq_desc *desc = irq_to_desc(irq); |
2db87321 UKK |
428 | int ret = -ENXIO; |
429 | ||
2f7e99bb TG |
430 | if (desc->irq_data.chip->irq_set_wake) |
431 | ret = desc->irq_data.chip->irq_set_wake(&desc->irq_data, on); | |
2db87321 UKK |
432 | |
433 | return ret; | |
434 | } | |
435 | ||
ba9a2331 TG |
436 | /** |
437 | * set_irq_wake - control irq power management wakeup | |
438 | * @irq: interrupt to control | |
439 | * @on: enable/disable power management wakeup | |
440 | * | |
15a647eb DB |
441 | * Enable/disable power management wakeup mode, which is |
442 | * disabled by default. Enables and disables must match, | |
443 | * just as they match for non-wakeup mode support. | |
444 | * | |
445 | * Wakeup mode lets this IRQ wake the system from sleep | |
446 | * states like "suspend to RAM". | |
ba9a2331 TG |
447 | */ |
448 | int set_irq_wake(unsigned int irq, unsigned int on) | |
449 | { | |
08678b08 | 450 | struct irq_desc *desc = irq_to_desc(irq); |
ba9a2331 | 451 | unsigned long flags; |
2db87321 | 452 | int ret = 0; |
ba9a2331 | 453 | |
15a647eb DB |
454 | /* wakeup-capable irqs can be shared between drivers that |
455 | * don't need to have the same sleep mode behaviors. | |
456 | */ | |
43abe43c | 457 | chip_bus_lock(desc); |
239007b8 | 458 | raw_spin_lock_irqsave(&desc->lock, flags); |
15a647eb | 459 | if (on) { |
2db87321 UKK |
460 | if (desc->wake_depth++ == 0) { |
461 | ret = set_irq_wake_real(irq, on); | |
462 | if (ret) | |
463 | desc->wake_depth = 0; | |
464 | else | |
465 | desc->status |= IRQ_WAKEUP; | |
466 | } | |
15a647eb DB |
467 | } else { |
468 | if (desc->wake_depth == 0) { | |
7a2c4770 | 469 | WARN(1, "Unbalanced IRQ %d wake disable\n", irq); |
2db87321 UKK |
470 | } else if (--desc->wake_depth == 0) { |
471 | ret = set_irq_wake_real(irq, on); | |
472 | if (ret) | |
473 | desc->wake_depth = 1; | |
474 | else | |
475 | desc->status &= ~IRQ_WAKEUP; | |
476 | } | |
15a647eb | 477 | } |
2db87321 | 478 | |
239007b8 | 479 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
43abe43c | 480 | chip_bus_sync_unlock(desc); |
ba9a2331 TG |
481 | return ret; |
482 | } | |
483 | EXPORT_SYMBOL(set_irq_wake); | |
484 | ||
1da177e4 LT |
485 | /* |
486 | * Internal function that tells the architecture code whether a | |
487 | * particular irq has been exclusively allocated or is available | |
488 | * for driver use. | |
489 | */ | |
490 | int can_request_irq(unsigned int irq, unsigned long irqflags) | |
491 | { | |
d3c60047 | 492 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 | 493 | struct irqaction *action; |
cc8c3b78 | 494 | unsigned long flags; |
1da177e4 | 495 | |
7d94f7ca YL |
496 | if (!desc) |
497 | return 0; | |
498 | ||
499 | if (desc->status & IRQ_NOREQUEST) | |
1da177e4 LT |
500 | return 0; |
501 | ||
cc8c3b78 | 502 | raw_spin_lock_irqsave(&desc->lock, flags); |
08678b08 | 503 | action = desc->action; |
1da177e4 | 504 | if (action) |
3cca53b0 | 505 | if (irqflags & action->flags & IRQF_SHARED) |
1da177e4 LT |
506 | action = NULL; |
507 | ||
cc8c3b78 TG |
508 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
509 | ||
1da177e4 LT |
510 | return !action; |
511 | } | |
512 | ||
6a6de9ef TG |
513 | void compat_irq_chip_set_default_handler(struct irq_desc *desc) |
514 | { | |
515 | /* | |
516 | * If the architecture still has not overriden | |
517 | * the flow handler then zap the default. This | |
518 | * should catch incorrect flow-type setting. | |
519 | */ | |
520 | if (desc->handle_irq == &handle_bad_irq) | |
521 | desc->handle_irq = NULL; | |
522 | } | |
523 | ||
0c5d1eb7 | 524 | int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, |
b2ba2c30 | 525 | unsigned long flags) |
82736f4d UKK |
526 | { |
527 | int ret; | |
6b8ff312 | 528 | struct irq_chip *chip = desc->irq_data.chip; |
82736f4d | 529 | |
b2ba2c30 | 530 | if (!chip || !chip->irq_set_type) { |
82736f4d UKK |
531 | /* |
532 | * IRQF_TRIGGER_* but the PIC does not support multiple | |
533 | * flow-types? | |
534 | */ | |
3ff68a6a | 535 | pr_debug("No set_type function for IRQ %d (%s)\n", irq, |
82736f4d UKK |
536 | chip ? (chip->name ? : "unknown") : "unknown"); |
537 | return 0; | |
538 | } | |
539 | ||
f2b662da | 540 | /* caller masked out all except trigger mode flags */ |
b2ba2c30 | 541 | ret = chip->irq_set_type(&desc->irq_data, flags); |
82736f4d UKK |
542 | |
543 | if (ret) | |
b2ba2c30 TG |
544 | pr_err("setting trigger mode %lu for irq %u failed (%pF)\n", |
545 | flags, irq, chip->irq_set_type); | |
0c5d1eb7 | 546 | else { |
f2b662da DB |
547 | if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) |
548 | flags |= IRQ_LEVEL; | |
0c5d1eb7 | 549 | /* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */ |
f2b662da DB |
550 | desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK); |
551 | desc->status |= flags; | |
46732475 | 552 | |
6b8ff312 TG |
553 | if (chip != desc->irq_data.chip) |
554 | irq_chip_set_defaults(desc->irq_data.chip); | |
0c5d1eb7 | 555 | } |
82736f4d UKK |
556 | |
557 | return ret; | |
558 | } | |
559 | ||
b25c340c TG |
560 | /* |
561 | * Default primary interrupt handler for threaded interrupts. Is | |
562 | * assigned as primary handler when request_threaded_irq is called | |
563 | * with handler == NULL. Useful for oneshot interrupts. | |
564 | */ | |
565 | static irqreturn_t irq_default_primary_handler(int irq, void *dev_id) | |
566 | { | |
567 | return IRQ_WAKE_THREAD; | |
568 | } | |
569 | ||
399b5da2 TG |
570 | /* |
571 | * Primary handler for nested threaded interrupts. Should never be | |
572 | * called. | |
573 | */ | |
574 | static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) | |
575 | { | |
576 | WARN(1, "Primary handler called for nested irq %d\n", irq); | |
577 | return IRQ_NONE; | |
578 | } | |
579 | ||
3aa551c9 TG |
580 | static int irq_wait_for_interrupt(struct irqaction *action) |
581 | { | |
582 | while (!kthread_should_stop()) { | |
583 | set_current_state(TASK_INTERRUPTIBLE); | |
f48fe81e TG |
584 | |
585 | if (test_and_clear_bit(IRQTF_RUNTHREAD, | |
586 | &action->thread_flags)) { | |
3aa551c9 TG |
587 | __set_current_state(TASK_RUNNING); |
588 | return 0; | |
f48fe81e TG |
589 | } |
590 | schedule(); | |
3aa551c9 TG |
591 | } |
592 | return -1; | |
593 | } | |
594 | ||
b25c340c TG |
595 | /* |
596 | * Oneshot interrupts keep the irq line masked until the threaded | |
597 | * handler finished. unmask if the interrupt has not been disabled and | |
598 | * is marked MASKED. | |
599 | */ | |
600 | static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc) | |
601 | { | |
0b1adaa0 | 602 | again: |
3876ec9e | 603 | chip_bus_lock(desc); |
239007b8 | 604 | raw_spin_lock_irq(&desc->lock); |
0b1adaa0 TG |
605 | |
606 | /* | |
607 | * Implausible though it may be we need to protect us against | |
608 | * the following scenario: | |
609 | * | |
610 | * The thread is faster done than the hard interrupt handler | |
611 | * on the other CPU. If we unmask the irq line then the | |
612 | * interrupt can come in again and masks the line, leaves due | |
613 | * to IRQ_INPROGRESS and the irq line is masked forever. | |
614 | */ | |
615 | if (unlikely(desc->status & IRQ_INPROGRESS)) { | |
616 | raw_spin_unlock_irq(&desc->lock); | |
3876ec9e | 617 | chip_bus_sync_unlock(desc); |
0b1adaa0 TG |
618 | cpu_relax(); |
619 | goto again; | |
620 | } | |
621 | ||
b25c340c TG |
622 | if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) { |
623 | desc->status &= ~IRQ_MASKED; | |
0eda58b7 | 624 | desc->irq_data.chip->irq_unmask(&desc->irq_data); |
b25c340c | 625 | } |
239007b8 | 626 | raw_spin_unlock_irq(&desc->lock); |
3876ec9e | 627 | chip_bus_sync_unlock(desc); |
b25c340c TG |
628 | } |
629 | ||
61f38261 | 630 | #ifdef CONFIG_SMP |
591d2fb0 TG |
631 | /* |
632 | * Check whether we need to change the affinity of the interrupt thread. | |
633 | */ | |
634 | static void | |
635 | irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) | |
636 | { | |
637 | cpumask_var_t mask; | |
638 | ||
639 | if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags)) | |
640 | return; | |
641 | ||
642 | /* | |
643 | * In case we are out of memory we set IRQTF_AFFINITY again and | |
644 | * try again next time | |
645 | */ | |
646 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { | |
647 | set_bit(IRQTF_AFFINITY, &action->thread_flags); | |
648 | return; | |
649 | } | |
650 | ||
239007b8 | 651 | raw_spin_lock_irq(&desc->lock); |
6b8ff312 | 652 | cpumask_copy(mask, desc->irq_data.affinity); |
239007b8 | 653 | raw_spin_unlock_irq(&desc->lock); |
591d2fb0 TG |
654 | |
655 | set_cpus_allowed_ptr(current, mask); | |
656 | free_cpumask_var(mask); | |
657 | } | |
61f38261 BP |
658 | #else |
659 | static inline void | |
660 | irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { } | |
661 | #endif | |
591d2fb0 | 662 | |
3aa551c9 TG |
663 | /* |
664 | * Interrupt handler thread | |
665 | */ | |
666 | static int irq_thread(void *data) | |
667 | { | |
c9b5f501 | 668 | static const struct sched_param param = { |
fe7de49f KM |
669 | .sched_priority = MAX_USER_RT_PRIO/2, |
670 | }; | |
3aa551c9 TG |
671 | struct irqaction *action = data; |
672 | struct irq_desc *desc = irq_to_desc(action->irq); | |
b25c340c | 673 | int wake, oneshot = desc->status & IRQ_ONESHOT; |
3aa551c9 TG |
674 | |
675 | sched_setscheduler(current, SCHED_FIFO, ¶m); | |
676 | current->irqaction = action; | |
677 | ||
678 | while (!irq_wait_for_interrupt(action)) { | |
679 | ||
591d2fb0 TG |
680 | irq_thread_check_affinity(desc, action); |
681 | ||
3aa551c9 TG |
682 | atomic_inc(&desc->threads_active); |
683 | ||
239007b8 | 684 | raw_spin_lock_irq(&desc->lock); |
3aa551c9 TG |
685 | if (unlikely(desc->status & IRQ_DISABLED)) { |
686 | /* | |
687 | * CHECKME: We might need a dedicated | |
688 | * IRQ_THREAD_PENDING flag here, which | |
689 | * retriggers the thread in check_irq_resend() | |
690 | * but AFAICT IRQ_PENDING should be fine as it | |
691 | * retriggers the interrupt itself --- tglx | |
692 | */ | |
693 | desc->status |= IRQ_PENDING; | |
239007b8 | 694 | raw_spin_unlock_irq(&desc->lock); |
3aa551c9 | 695 | } else { |
239007b8 | 696 | raw_spin_unlock_irq(&desc->lock); |
3aa551c9 TG |
697 | |
698 | action->thread_fn(action->irq, action->dev_id); | |
b25c340c TG |
699 | |
700 | if (oneshot) | |
701 | irq_finalize_oneshot(action->irq, desc); | |
3aa551c9 TG |
702 | } |
703 | ||
704 | wake = atomic_dec_and_test(&desc->threads_active); | |
705 | ||
706 | if (wake && waitqueue_active(&desc->wait_for_threads)) | |
707 | wake_up(&desc->wait_for_threads); | |
708 | } | |
709 | ||
710 | /* | |
711 | * Clear irqaction. Otherwise exit_irq_thread() would make | |
712 | * fuzz about an active irq thread going into nirvana. | |
713 | */ | |
714 | current->irqaction = NULL; | |
715 | return 0; | |
716 | } | |
717 | ||
718 | /* | |
719 | * Called from do_exit() | |
720 | */ | |
721 | void exit_irq_thread(void) | |
722 | { | |
723 | struct task_struct *tsk = current; | |
724 | ||
725 | if (!tsk->irqaction) | |
726 | return; | |
727 | ||
728 | printk(KERN_ERR | |
729 | "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n", | |
730 | tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq); | |
731 | ||
732 | /* | |
733 | * Set the THREAD DIED flag to prevent further wakeups of the | |
734 | * soon to be gone threaded handler. | |
735 | */ | |
736 | set_bit(IRQTF_DIED, &tsk->irqaction->flags); | |
737 | } | |
738 | ||
1da177e4 LT |
739 | /* |
740 | * Internal function to register an irqaction - typically used to | |
741 | * allocate special interrupts that are part of the architecture. | |
742 | */ | |
d3c60047 | 743 | static int |
327ec569 | 744 | __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) |
1da177e4 | 745 | { |
f17c7545 | 746 | struct irqaction *old, **old_ptr; |
8b126b77 | 747 | const char *old_name = NULL; |
1da177e4 | 748 | unsigned long flags; |
399b5da2 | 749 | int nested, shared = 0; |
82736f4d | 750 | int ret; |
1da177e4 | 751 | |
7d94f7ca | 752 | if (!desc) |
c2b5a251 MW |
753 | return -EINVAL; |
754 | ||
6b8ff312 | 755 | if (desc->irq_data.chip == &no_irq_chip) |
1da177e4 LT |
756 | return -ENOSYS; |
757 | /* | |
758 | * Some drivers like serial.c use request_irq() heavily, | |
759 | * so we have to be careful not to interfere with a | |
760 | * running system. | |
761 | */ | |
3cca53b0 | 762 | if (new->flags & IRQF_SAMPLE_RANDOM) { |
1da177e4 LT |
763 | /* |
764 | * This function might sleep, we want to call it first, | |
765 | * outside of the atomic block. | |
766 | * Yes, this might clear the entropy pool if the wrong | |
767 | * driver is attempted to be loaded, without actually | |
768 | * installing a new handler, but is this really a problem, | |
769 | * only the sysadmin is able to do this. | |
770 | */ | |
771 | rand_initialize_irq(irq); | |
772 | } | |
773 | ||
b25c340c TG |
774 | /* Oneshot interrupts are not allowed with shared */ |
775 | if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED)) | |
776 | return -EINVAL; | |
777 | ||
3aa551c9 | 778 | /* |
399b5da2 TG |
779 | * Check whether the interrupt nests into another interrupt |
780 | * thread. | |
781 | */ | |
782 | nested = desc->status & IRQ_NESTED_THREAD; | |
783 | if (nested) { | |
784 | if (!new->thread_fn) | |
785 | return -EINVAL; | |
786 | /* | |
787 | * Replace the primary handler which was provided from | |
788 | * the driver for non nested interrupt handling by the | |
789 | * dummy function which warns when called. | |
790 | */ | |
791 | new->handler = irq_nested_primary_handler; | |
792 | } | |
793 | ||
3aa551c9 | 794 | /* |
399b5da2 TG |
795 | * Create a handler thread when a thread function is supplied |
796 | * and the interrupt does not nest into another interrupt | |
797 | * thread. | |
3aa551c9 | 798 | */ |
399b5da2 | 799 | if (new->thread_fn && !nested) { |
3aa551c9 TG |
800 | struct task_struct *t; |
801 | ||
802 | t = kthread_create(irq_thread, new, "irq/%d-%s", irq, | |
803 | new->name); | |
804 | if (IS_ERR(t)) | |
805 | return PTR_ERR(t); | |
806 | /* | |
807 | * We keep the reference to the task struct even if | |
808 | * the thread dies to avoid that the interrupt code | |
809 | * references an already freed task_struct. | |
810 | */ | |
811 | get_task_struct(t); | |
812 | new->thread = t; | |
3aa551c9 TG |
813 | } |
814 | ||
1da177e4 LT |
815 | /* |
816 | * The following block of code has to be executed atomically | |
817 | */ | |
239007b8 | 818 | raw_spin_lock_irqsave(&desc->lock, flags); |
f17c7545 IM |
819 | old_ptr = &desc->action; |
820 | old = *old_ptr; | |
06fcb0c6 | 821 | if (old) { |
e76de9f8 TG |
822 | /* |
823 | * Can't share interrupts unless both agree to and are | |
824 | * the same type (level, edge, polarity). So both flag | |
3cca53b0 | 825 | * fields must have IRQF_SHARED set and the bits which |
e76de9f8 TG |
826 | * set the trigger type must match. |
827 | */ | |
3cca53b0 | 828 | if (!((old->flags & new->flags) & IRQF_SHARED) || |
8b126b77 AM |
829 | ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) { |
830 | old_name = old->name; | |
f5163427 | 831 | goto mismatch; |
8b126b77 | 832 | } |
f5163427 | 833 | |
284c6680 | 834 | #if defined(CONFIG_IRQ_PER_CPU) |
f5163427 | 835 | /* All handlers must agree on per-cpuness */ |
3cca53b0 TG |
836 | if ((old->flags & IRQF_PERCPU) != |
837 | (new->flags & IRQF_PERCPU)) | |
f5163427 DS |
838 | goto mismatch; |
839 | #endif | |
1da177e4 LT |
840 | |
841 | /* add new interrupt at end of irq queue */ | |
842 | do { | |
f17c7545 IM |
843 | old_ptr = &old->next; |
844 | old = *old_ptr; | |
1da177e4 LT |
845 | } while (old); |
846 | shared = 1; | |
847 | } | |
848 | ||
1da177e4 | 849 | if (!shared) { |
6b8ff312 | 850 | irq_chip_set_defaults(desc->irq_data.chip); |
e76de9f8 | 851 | |
3aa551c9 TG |
852 | init_waitqueue_head(&desc->wait_for_threads); |
853 | ||
e76de9f8 | 854 | /* Setup the type (level, edge polarity) if configured: */ |
3cca53b0 | 855 | if (new->flags & IRQF_TRIGGER_MASK) { |
f2b662da DB |
856 | ret = __irq_set_trigger(desc, irq, |
857 | new->flags & IRQF_TRIGGER_MASK); | |
82736f4d | 858 | |
3aa551c9 TG |
859 | if (ret) |
860 | goto out_thread; | |
e76de9f8 TG |
861 | } else |
862 | compat_irq_chip_set_default_handler(desc); | |
82736f4d UKK |
863 | #if defined(CONFIG_IRQ_PER_CPU) |
864 | if (new->flags & IRQF_PERCPU) | |
865 | desc->status |= IRQ_PER_CPU; | |
866 | #endif | |
6a6de9ef | 867 | |
b25c340c | 868 | desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT | |
1adb0850 | 869 | IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED); |
94d39e1f | 870 | |
b25c340c TG |
871 | if (new->flags & IRQF_ONESHOT) |
872 | desc->status |= IRQ_ONESHOT; | |
873 | ||
94d39e1f TG |
874 | if (!(desc->status & IRQ_NOAUTOEN)) { |
875 | desc->depth = 0; | |
876 | desc->status &= ~IRQ_DISABLED; | |
37e12df7 | 877 | desc->irq_data.chip->irq_startup(&desc->irq_data); |
e76de9f8 TG |
878 | } else |
879 | /* Undo nested disables: */ | |
880 | desc->depth = 1; | |
18404756 | 881 | |
612e3684 TG |
882 | /* Exclude IRQ from balancing if requested */ |
883 | if (new->flags & IRQF_NOBALANCING) | |
884 | desc->status |= IRQ_NO_BALANCING; | |
885 | ||
18404756 | 886 | /* Set default affinity mask once everything is setup */ |
548c8933 | 887 | setup_affinity(irq, desc); |
0c5d1eb7 DB |
888 | |
889 | } else if ((new->flags & IRQF_TRIGGER_MASK) | |
890 | && (new->flags & IRQF_TRIGGER_MASK) | |
891 | != (desc->status & IRQ_TYPE_SENSE_MASK)) { | |
892 | /* hope the handler works with the actual trigger mode... */ | |
893 | pr_warning("IRQ %d uses trigger mode %d; requested %d\n", | |
894 | irq, (int)(desc->status & IRQ_TYPE_SENSE_MASK), | |
895 | (int)(new->flags & IRQF_TRIGGER_MASK)); | |
1da177e4 | 896 | } |
82736f4d | 897 | |
69ab8494 | 898 | new->irq = irq; |
f17c7545 | 899 | *old_ptr = new; |
82736f4d | 900 | |
8528b0f1 LT |
901 | /* Reset broken irq detection when installing new handler */ |
902 | desc->irq_count = 0; | |
903 | desc->irqs_unhandled = 0; | |
1adb0850 TG |
904 | |
905 | /* | |
906 | * Check whether we disabled the irq via the spurious handler | |
907 | * before. Reenable it and give it another chance. | |
908 | */ | |
909 | if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) { | |
910 | desc->status &= ~IRQ_SPURIOUS_DISABLED; | |
0a0c5168 | 911 | __enable_irq(desc, irq, false); |
1adb0850 TG |
912 | } |
913 | ||
239007b8 | 914 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
1da177e4 | 915 | |
69ab8494 TG |
916 | /* |
917 | * Strictly no need to wake it up, but hung_task complains | |
918 | * when no hard interrupt wakes the thread up. | |
919 | */ | |
920 | if (new->thread) | |
921 | wake_up_process(new->thread); | |
922 | ||
2c6927a3 | 923 | register_irq_proc(irq, desc); |
1da177e4 LT |
924 | new->dir = NULL; |
925 | register_handler_proc(irq, new); | |
926 | ||
927 | return 0; | |
f5163427 DS |
928 | |
929 | mismatch: | |
3f050447 | 930 | #ifdef CONFIG_DEBUG_SHIRQ |
3cca53b0 | 931 | if (!(new->flags & IRQF_PROBE_SHARED)) { |
e8c4b9d0 | 932 | printk(KERN_ERR "IRQ handler type mismatch for IRQ %d\n", irq); |
8b126b77 AM |
933 | if (old_name) |
934 | printk(KERN_ERR "current handler: %s\n", old_name); | |
13e87ec6 AM |
935 | dump_stack(); |
936 | } | |
3f050447 | 937 | #endif |
3aa551c9 TG |
938 | ret = -EBUSY; |
939 | ||
940 | out_thread: | |
239007b8 | 941 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
3aa551c9 TG |
942 | if (new->thread) { |
943 | struct task_struct *t = new->thread; | |
944 | ||
945 | new->thread = NULL; | |
946 | if (likely(!test_bit(IRQTF_DIED, &new->thread_flags))) | |
947 | kthread_stop(t); | |
948 | put_task_struct(t); | |
949 | } | |
950 | return ret; | |
1da177e4 LT |
951 | } |
952 | ||
d3c60047 TG |
953 | /** |
954 | * setup_irq - setup an interrupt | |
955 | * @irq: Interrupt line to setup | |
956 | * @act: irqaction for the interrupt | |
957 | * | |
958 | * Used to statically setup interrupts in the early boot process. | |
959 | */ | |
960 | int setup_irq(unsigned int irq, struct irqaction *act) | |
961 | { | |
986c011d | 962 | int retval; |
d3c60047 TG |
963 | struct irq_desc *desc = irq_to_desc(irq); |
964 | ||
986c011d DD |
965 | chip_bus_lock(desc); |
966 | retval = __setup_irq(irq, desc, act); | |
967 | chip_bus_sync_unlock(desc); | |
968 | ||
969 | return retval; | |
d3c60047 | 970 | } |
eb53b4e8 | 971 | EXPORT_SYMBOL_GPL(setup_irq); |
d3c60047 | 972 | |
cbf94f06 MD |
973 | /* |
974 | * Internal function to unregister an irqaction - used to free | |
975 | * regular and special interrupts that are part of the architecture. | |
1da177e4 | 976 | */ |
cbf94f06 | 977 | static struct irqaction *__free_irq(unsigned int irq, void *dev_id) |
1da177e4 | 978 | { |
d3c60047 | 979 | struct irq_desc *desc = irq_to_desc(irq); |
f17c7545 | 980 | struct irqaction *action, **action_ptr; |
1da177e4 LT |
981 | unsigned long flags; |
982 | ||
ae88a23b | 983 | WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq); |
7d94f7ca | 984 | |
7d94f7ca | 985 | if (!desc) |
f21cfb25 | 986 | return NULL; |
1da177e4 | 987 | |
239007b8 | 988 | raw_spin_lock_irqsave(&desc->lock, flags); |
ae88a23b IM |
989 | |
990 | /* | |
991 | * There can be multiple actions per IRQ descriptor, find the right | |
992 | * one based on the dev_id: | |
993 | */ | |
f17c7545 | 994 | action_ptr = &desc->action; |
1da177e4 | 995 | for (;;) { |
f17c7545 | 996 | action = *action_ptr; |
1da177e4 | 997 | |
ae88a23b IM |
998 | if (!action) { |
999 | WARN(1, "Trying to free already-free IRQ %d\n", irq); | |
239007b8 | 1000 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
1da177e4 | 1001 | |
f21cfb25 | 1002 | return NULL; |
ae88a23b | 1003 | } |
1da177e4 | 1004 | |
8316e381 IM |
1005 | if (action->dev_id == dev_id) |
1006 | break; | |
f17c7545 | 1007 | action_ptr = &action->next; |
ae88a23b | 1008 | } |
dbce706e | 1009 | |
ae88a23b | 1010 | /* Found it - now remove it from the list of entries: */ |
f17c7545 | 1011 | *action_ptr = action->next; |
ae88a23b IM |
1012 | |
1013 | /* Currently used only by UML, might disappear one day: */ | |
b77d6adc | 1014 | #ifdef CONFIG_IRQ_RELEASE_METHOD |
6b8ff312 TG |
1015 | if (desc->irq_data.chip->release) |
1016 | desc->irq_data.chip->release(irq, dev_id); | |
b77d6adc | 1017 | #endif |
dbce706e | 1018 | |
ae88a23b IM |
1019 | /* If this was the last handler, shut down the IRQ line: */ |
1020 | if (!desc->action) { | |
1021 | desc->status |= IRQ_DISABLED; | |
bc310dda TG |
1022 | if (desc->irq_data.chip->irq_shutdown) |
1023 | desc->irq_data.chip->irq_shutdown(&desc->irq_data); | |
ae88a23b | 1024 | else |
bc310dda | 1025 | desc->irq_data.chip->irq_disable(&desc->irq_data); |
ae88a23b | 1026 | } |
3aa551c9 | 1027 | |
e7a297b0 PWJ |
1028 | #ifdef CONFIG_SMP |
1029 | /* make sure affinity_hint is cleaned up */ | |
1030 | if (WARN_ON_ONCE(desc->affinity_hint)) | |
1031 | desc->affinity_hint = NULL; | |
1032 | #endif | |
1033 | ||
239007b8 | 1034 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
ae88a23b IM |
1035 | |
1036 | unregister_handler_proc(irq, action); | |
1037 | ||
1038 | /* Make sure it's not being used on another CPU: */ | |
1039 | synchronize_irq(irq); | |
1da177e4 | 1040 | |
70edcd77 | 1041 | #ifdef CONFIG_DEBUG_SHIRQ |
ae88a23b IM |
1042 | /* |
1043 | * It's a shared IRQ -- the driver ought to be prepared for an IRQ | |
1044 | * event to happen even now it's being freed, so let's make sure that | |
1045 | * is so by doing an extra call to the handler .... | |
1046 | * | |
1047 | * ( We do this after actually deregistering it, to make sure that a | |
1048 | * 'real' IRQ doesn't run in * parallel with our fake. ) | |
1049 | */ | |
1050 | if (action->flags & IRQF_SHARED) { | |
1051 | local_irq_save(flags); | |
1052 | action->handler(irq, dev_id); | |
1053 | local_irq_restore(flags); | |
1da177e4 | 1054 | } |
ae88a23b | 1055 | #endif |
2d860ad7 LT |
1056 | |
1057 | if (action->thread) { | |
1058 | if (!test_bit(IRQTF_DIED, &action->thread_flags)) | |
1059 | kthread_stop(action->thread); | |
1060 | put_task_struct(action->thread); | |
1061 | } | |
1062 | ||
f21cfb25 MD |
1063 | return action; |
1064 | } | |
1065 | ||
cbf94f06 MD |
1066 | /** |
1067 | * remove_irq - free an interrupt | |
1068 | * @irq: Interrupt line to free | |
1069 | * @act: irqaction for the interrupt | |
1070 | * | |
1071 | * Used to remove interrupts statically setup by the early boot process. | |
1072 | */ | |
1073 | void remove_irq(unsigned int irq, struct irqaction *act) | |
1074 | { | |
1075 | __free_irq(irq, act->dev_id); | |
1076 | } | |
eb53b4e8 | 1077 | EXPORT_SYMBOL_GPL(remove_irq); |
cbf94f06 | 1078 | |
f21cfb25 MD |
1079 | /** |
1080 | * free_irq - free an interrupt allocated with request_irq | |
1081 | * @irq: Interrupt line to free | |
1082 | * @dev_id: Device identity to free | |
1083 | * | |
1084 | * Remove an interrupt handler. The handler is removed and if the | |
1085 | * interrupt line is no longer in use by any driver it is disabled. | |
1086 | * On a shared IRQ the caller must ensure the interrupt is disabled | |
1087 | * on the card it drives before calling this function. The function | |
1088 | * does not return until any executing interrupts for this IRQ | |
1089 | * have completed. | |
1090 | * | |
1091 | * This function must not be called from interrupt context. | |
1092 | */ | |
1093 | void free_irq(unsigned int irq, void *dev_id) | |
1094 | { | |
70aedd24 TG |
1095 | struct irq_desc *desc = irq_to_desc(irq); |
1096 | ||
1097 | if (!desc) | |
1098 | return; | |
1099 | ||
cd7eab44 BH |
1100 | #ifdef CONFIG_SMP |
1101 | if (WARN_ON(desc->affinity_notify)) | |
1102 | desc->affinity_notify = NULL; | |
1103 | #endif | |
1104 | ||
3876ec9e | 1105 | chip_bus_lock(desc); |
cbf94f06 | 1106 | kfree(__free_irq(irq, dev_id)); |
3876ec9e | 1107 | chip_bus_sync_unlock(desc); |
1da177e4 | 1108 | } |
1da177e4 LT |
1109 | EXPORT_SYMBOL(free_irq); |
1110 | ||
1111 | /** | |
3aa551c9 | 1112 | * request_threaded_irq - allocate an interrupt line |
1da177e4 | 1113 | * @irq: Interrupt line to allocate |
3aa551c9 TG |
1114 | * @handler: Function to be called when the IRQ occurs. |
1115 | * Primary handler for threaded interrupts | |
b25c340c TG |
1116 | * If NULL and thread_fn != NULL the default |
1117 | * primary handler is installed | |
f48fe81e TG |
1118 | * @thread_fn: Function called from the irq handler thread |
1119 | * If NULL, no irq thread is created | |
1da177e4 LT |
1120 | * @irqflags: Interrupt type flags |
1121 | * @devname: An ascii name for the claiming device | |
1122 | * @dev_id: A cookie passed back to the handler function | |
1123 | * | |
1124 | * This call allocates interrupt resources and enables the | |
1125 | * interrupt line and IRQ handling. From the point this | |
1126 | * call is made your handler function may be invoked. Since | |
1127 | * your handler function must clear any interrupt the board | |
1128 | * raises, you must take care both to initialise your hardware | |
1129 | * and to set up the interrupt handler in the right order. | |
1130 | * | |
3aa551c9 TG |
1131 | * If you want to set up a threaded irq handler for your device |
1132 | * then you need to supply @handler and @thread_fn. @handler ist | |
1133 | * still called in hard interrupt context and has to check | |
1134 | * whether the interrupt originates from the device. If yes it | |
1135 | * needs to disable the interrupt on the device and return | |
39a2eddb | 1136 | * IRQ_WAKE_THREAD which will wake up the handler thread and run |
3aa551c9 TG |
1137 | * @thread_fn. This split handler design is necessary to support |
1138 | * shared interrupts. | |
1139 | * | |
1da177e4 LT |
1140 | * Dev_id must be globally unique. Normally the address of the |
1141 | * device data structure is used as the cookie. Since the handler | |
1142 | * receives this value it makes sense to use it. | |
1143 | * | |
1144 | * If your interrupt is shared you must pass a non NULL dev_id | |
1145 | * as this is required when freeing the interrupt. | |
1146 | * | |
1147 | * Flags: | |
1148 | * | |
3cca53b0 | 1149 | * IRQF_SHARED Interrupt is shared |
3cca53b0 | 1150 | * IRQF_SAMPLE_RANDOM The interrupt can be used for entropy |
0c5d1eb7 | 1151 | * IRQF_TRIGGER_* Specify active edge(s) or level |
1da177e4 LT |
1152 | * |
1153 | */ | |
3aa551c9 TG |
1154 | int request_threaded_irq(unsigned int irq, irq_handler_t handler, |
1155 | irq_handler_t thread_fn, unsigned long irqflags, | |
1156 | const char *devname, void *dev_id) | |
1da177e4 | 1157 | { |
06fcb0c6 | 1158 | struct irqaction *action; |
08678b08 | 1159 | struct irq_desc *desc; |
d3c60047 | 1160 | int retval; |
1da177e4 LT |
1161 | |
1162 | /* | |
1163 | * Sanity-check: shared interrupts must pass in a real dev-ID, | |
1164 | * otherwise we'll have trouble later trying to figure out | |
1165 | * which interrupt is which (messes up the interrupt freeing | |
1166 | * logic etc). | |
1167 | */ | |
3cca53b0 | 1168 | if ((irqflags & IRQF_SHARED) && !dev_id) |
1da177e4 | 1169 | return -EINVAL; |
7d94f7ca | 1170 | |
cb5bc832 | 1171 | desc = irq_to_desc(irq); |
7d94f7ca | 1172 | if (!desc) |
1da177e4 | 1173 | return -EINVAL; |
7d94f7ca | 1174 | |
08678b08 | 1175 | if (desc->status & IRQ_NOREQUEST) |
6550c775 | 1176 | return -EINVAL; |
b25c340c TG |
1177 | |
1178 | if (!handler) { | |
1179 | if (!thread_fn) | |
1180 | return -EINVAL; | |
1181 | handler = irq_default_primary_handler; | |
1182 | } | |
1da177e4 | 1183 | |
45535732 | 1184 | action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); |
1da177e4 LT |
1185 | if (!action) |
1186 | return -ENOMEM; | |
1187 | ||
1188 | action->handler = handler; | |
3aa551c9 | 1189 | action->thread_fn = thread_fn; |
1da177e4 | 1190 | action->flags = irqflags; |
1da177e4 | 1191 | action->name = devname; |
1da177e4 LT |
1192 | action->dev_id = dev_id; |
1193 | ||
3876ec9e | 1194 | chip_bus_lock(desc); |
d3c60047 | 1195 | retval = __setup_irq(irq, desc, action); |
3876ec9e | 1196 | chip_bus_sync_unlock(desc); |
70aedd24 | 1197 | |
377bf1e4 AV |
1198 | if (retval) |
1199 | kfree(action); | |
1200 | ||
6d83f94d | 1201 | #ifdef CONFIG_DEBUG_SHIRQ_FIXME |
6ce51c43 | 1202 | if (!retval && (irqflags & IRQF_SHARED)) { |
a304e1b8 DW |
1203 | /* |
1204 | * It's a shared IRQ -- the driver ought to be prepared for it | |
1205 | * to happen immediately, so let's make sure.... | |
377bf1e4 AV |
1206 | * We disable the irq to make sure that a 'real' IRQ doesn't |
1207 | * run in parallel with our fake. | |
a304e1b8 | 1208 | */ |
59845b1f | 1209 | unsigned long flags; |
a304e1b8 | 1210 | |
377bf1e4 | 1211 | disable_irq(irq); |
59845b1f | 1212 | local_irq_save(flags); |
377bf1e4 | 1213 | |
59845b1f | 1214 | handler(irq, dev_id); |
377bf1e4 | 1215 | |
59845b1f | 1216 | local_irq_restore(flags); |
377bf1e4 | 1217 | enable_irq(irq); |
a304e1b8 DW |
1218 | } |
1219 | #endif | |
1da177e4 LT |
1220 | return retval; |
1221 | } | |
3aa551c9 | 1222 | EXPORT_SYMBOL(request_threaded_irq); |
ae731f8d MZ |
1223 | |
1224 | /** | |
1225 | * request_any_context_irq - allocate an interrupt line | |
1226 | * @irq: Interrupt line to allocate | |
1227 | * @handler: Function to be called when the IRQ occurs. | |
1228 | * Threaded handler for threaded interrupts. | |
1229 | * @flags: Interrupt type flags | |
1230 | * @name: An ascii name for the claiming device | |
1231 | * @dev_id: A cookie passed back to the handler function | |
1232 | * | |
1233 | * This call allocates interrupt resources and enables the | |
1234 | * interrupt line and IRQ handling. It selects either a | |
1235 | * hardirq or threaded handling method depending on the | |
1236 | * context. | |
1237 | * | |
1238 | * On failure, it returns a negative value. On success, | |
1239 | * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED. | |
1240 | */ | |
1241 | int request_any_context_irq(unsigned int irq, irq_handler_t handler, | |
1242 | unsigned long flags, const char *name, void *dev_id) | |
1243 | { | |
1244 | struct irq_desc *desc = irq_to_desc(irq); | |
1245 | int ret; | |
1246 | ||
1247 | if (!desc) | |
1248 | return -EINVAL; | |
1249 | ||
1250 | if (desc->status & IRQ_NESTED_THREAD) { | |
1251 | ret = request_threaded_irq(irq, NULL, handler, | |
1252 | flags, name, dev_id); | |
1253 | return !ret ? IRQC_IS_NESTED : ret; | |
1254 | } | |
1255 | ||
1256 | ret = request_irq(irq, handler, flags, name, dev_id); | |
1257 | return !ret ? IRQC_IS_HARDIRQ : ret; | |
1258 | } | |
1259 | EXPORT_SYMBOL_GPL(request_any_context_irq); |