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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. */ | |
49 | spin_lock_irqsave(&desc->lock, flags); | |
50 | status = desc->status; | |
51 | spin_unlock_irqrestore(&desc->lock, flags); | |
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 TG |
75 | |
76 | if (CHECK_IRQ_PER_CPU(desc->status) || !desc->chip || | |
77 | !desc->chip->set_affinity) | |
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); |
f6d87f4b | 112 | unsigned long flags; |
771ee3b0 TG |
113 | |
114 | if (!desc->chip->set_affinity) | |
115 | return -EINVAL; | |
116 | ||
f6d87f4b TG |
117 | spin_lock_irqsave(&desc->lock, flags); |
118 | ||
771ee3b0 | 119 | #ifdef CONFIG_GENERIC_PENDING_IRQ |
57b150cc YL |
120 | if (desc->status & IRQ_MOVE_PCNTXT) { |
121 | if (!desc->chip->set_affinity(irq, cpumask)) { | |
122 | cpumask_copy(desc->affinity, cpumask); | |
591d2fb0 | 123 | irq_set_thread_affinity(desc); |
57b150cc YL |
124 | } |
125 | } | |
6ec3cfec | 126 | else { |
f6d87f4b | 127 | desc->status |= IRQ_MOVE_PENDING; |
7f7ace0c | 128 | cpumask_copy(desc->pending_mask, cpumask); |
f6d87f4b | 129 | } |
771ee3b0 | 130 | #else |
57b150cc YL |
131 | if (!desc->chip->set_affinity(irq, cpumask)) { |
132 | cpumask_copy(desc->affinity, cpumask); | |
591d2fb0 | 133 | irq_set_thread_affinity(desc); |
57b150cc | 134 | } |
771ee3b0 | 135 | #endif |
f6d87f4b TG |
136 | desc->status |= IRQ_AFFINITY_SET; |
137 | spin_unlock_irqrestore(&desc->lock, flags); | |
771ee3b0 TG |
138 | return 0; |
139 | } | |
140 | ||
18404756 MK |
141 | #ifndef CONFIG_AUTO_IRQ_AFFINITY |
142 | /* | |
143 | * Generic version of the affinity autoselector. | |
144 | */ | |
548c8933 | 145 | static int setup_affinity(unsigned int irq, struct irq_desc *desc) |
18404756 | 146 | { |
18404756 MK |
147 | if (!irq_can_set_affinity(irq)) |
148 | return 0; | |
149 | ||
f6d87f4b TG |
150 | /* |
151 | * Preserve an userspace affinity setup, but make sure that | |
152 | * one of the targets is online. | |
153 | */ | |
612e3684 | 154 | if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) { |
7f7ace0c | 155 | if (cpumask_any_and(desc->affinity, cpu_online_mask) |
0de26520 RR |
156 | < nr_cpu_ids) |
157 | goto set_affinity; | |
f6d87f4b TG |
158 | else |
159 | desc->status &= ~IRQ_AFFINITY_SET; | |
160 | } | |
161 | ||
7f7ace0c | 162 | cpumask_and(desc->affinity, cpu_online_mask, irq_default_affinity); |
0de26520 | 163 | set_affinity: |
7f7ace0c | 164 | desc->chip->set_affinity(irq, desc->affinity); |
18404756 | 165 | |
18404756 MK |
166 | return 0; |
167 | } | |
f6d87f4b | 168 | #else |
548c8933 | 169 | static inline int setup_affinity(unsigned int irq, struct irq_desc *d) |
f6d87f4b TG |
170 | { |
171 | return irq_select_affinity(irq); | |
172 | } | |
18404756 MK |
173 | #endif |
174 | ||
f6d87f4b TG |
175 | /* |
176 | * Called when affinity is set via /proc/irq | |
177 | */ | |
178 | int irq_select_affinity_usr(unsigned int irq) | |
179 | { | |
180 | struct irq_desc *desc = irq_to_desc(irq); | |
181 | unsigned long flags; | |
182 | int ret; | |
183 | ||
184 | spin_lock_irqsave(&desc->lock, flags); | |
548c8933 | 185 | ret = setup_affinity(irq, desc); |
3aa551c9 | 186 | if (!ret) |
591d2fb0 | 187 | irq_set_thread_affinity(desc); |
f6d87f4b TG |
188 | spin_unlock_irqrestore(&desc->lock, flags); |
189 | ||
190 | return ret; | |
191 | } | |
192 | ||
193 | #else | |
548c8933 | 194 | static inline int setup_affinity(unsigned int irq, struct irq_desc *desc) |
f6d87f4b TG |
195 | { |
196 | return 0; | |
197 | } | |
1da177e4 LT |
198 | #endif |
199 | ||
0a0c5168 RW |
200 | void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend) |
201 | { | |
202 | if (suspend) { | |
203 | if (!desc->action || (desc->action->flags & IRQF_TIMER)) | |
204 | return; | |
205 | desc->status |= IRQ_SUSPENDED; | |
206 | } | |
207 | ||
208 | if (!desc->depth++) { | |
209 | desc->status |= IRQ_DISABLED; | |
210 | desc->chip->disable(irq); | |
211 | } | |
212 | } | |
213 | ||
1da177e4 LT |
214 | /** |
215 | * disable_irq_nosync - disable an irq without waiting | |
216 | * @irq: Interrupt to disable | |
217 | * | |
218 | * Disable the selected interrupt line. Disables and Enables are | |
219 | * nested. | |
220 | * Unlike disable_irq(), this function does not ensure existing | |
221 | * instances of the IRQ handler have completed before returning. | |
222 | * | |
223 | * This function may be called from IRQ context. | |
224 | */ | |
225 | void disable_irq_nosync(unsigned int irq) | |
226 | { | |
d3c60047 | 227 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 LT |
228 | unsigned long flags; |
229 | ||
7d94f7ca | 230 | if (!desc) |
c2b5a251 MW |
231 | return; |
232 | ||
70aedd24 | 233 | chip_bus_lock(irq, desc); |
1da177e4 | 234 | spin_lock_irqsave(&desc->lock, flags); |
0a0c5168 | 235 | __disable_irq(desc, irq, false); |
1da177e4 | 236 | spin_unlock_irqrestore(&desc->lock, flags); |
70aedd24 | 237 | chip_bus_sync_unlock(irq, desc); |
1da177e4 | 238 | } |
1da177e4 LT |
239 | EXPORT_SYMBOL(disable_irq_nosync); |
240 | ||
241 | /** | |
242 | * disable_irq - disable an irq and wait for completion | |
243 | * @irq: Interrupt to disable | |
244 | * | |
245 | * Disable the selected interrupt line. Enables and Disables are | |
246 | * nested. | |
247 | * This function waits for any pending IRQ handlers for this interrupt | |
248 | * to complete before returning. If you use this function while | |
249 | * holding a resource the IRQ handler may need you will deadlock. | |
250 | * | |
251 | * This function may be called - with care - from IRQ context. | |
252 | */ | |
253 | void disable_irq(unsigned int irq) | |
254 | { | |
d3c60047 | 255 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 | 256 | |
7d94f7ca | 257 | if (!desc) |
c2b5a251 MW |
258 | return; |
259 | ||
1da177e4 LT |
260 | disable_irq_nosync(irq); |
261 | if (desc->action) | |
262 | synchronize_irq(irq); | |
263 | } | |
1da177e4 LT |
264 | EXPORT_SYMBOL(disable_irq); |
265 | ||
0a0c5168 | 266 | void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) |
1adb0850 | 267 | { |
0a0c5168 RW |
268 | if (resume) |
269 | desc->status &= ~IRQ_SUSPENDED; | |
270 | ||
1adb0850 TG |
271 | switch (desc->depth) { |
272 | case 0: | |
0a0c5168 | 273 | err_out: |
b8c512f6 | 274 | WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq); |
1adb0850 TG |
275 | break; |
276 | case 1: { | |
277 | unsigned int status = desc->status & ~IRQ_DISABLED; | |
278 | ||
0a0c5168 RW |
279 | if (desc->status & IRQ_SUSPENDED) |
280 | goto err_out; | |
1adb0850 TG |
281 | /* Prevent probing on this irq: */ |
282 | desc->status = status | IRQ_NOPROBE; | |
283 | check_irq_resend(desc, irq); | |
284 | /* fall-through */ | |
285 | } | |
286 | default: | |
287 | desc->depth--; | |
288 | } | |
289 | } | |
290 | ||
1da177e4 LT |
291 | /** |
292 | * enable_irq - enable handling of an irq | |
293 | * @irq: Interrupt to enable | |
294 | * | |
295 | * Undoes the effect of one call to disable_irq(). If this | |
296 | * matches the last disable, processing of interrupts on this | |
297 | * IRQ line is re-enabled. | |
298 | * | |
70aedd24 TG |
299 | * This function may be called from IRQ context only when |
300 | * desc->chip->bus_lock and desc->chip->bus_sync_unlock are NULL ! | |
1da177e4 LT |
301 | */ |
302 | void enable_irq(unsigned int irq) | |
303 | { | |
d3c60047 | 304 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 LT |
305 | unsigned long flags; |
306 | ||
7d94f7ca | 307 | if (!desc) |
c2b5a251 MW |
308 | return; |
309 | ||
70aedd24 | 310 | chip_bus_lock(irq, desc); |
1da177e4 | 311 | spin_lock_irqsave(&desc->lock, flags); |
0a0c5168 | 312 | __enable_irq(desc, irq, false); |
1da177e4 | 313 | spin_unlock_irqrestore(&desc->lock, flags); |
70aedd24 | 314 | chip_bus_sync_unlock(irq, desc); |
1da177e4 | 315 | } |
1da177e4 LT |
316 | EXPORT_SYMBOL(enable_irq); |
317 | ||
0c5d1eb7 | 318 | static int set_irq_wake_real(unsigned int irq, unsigned int on) |
2db87321 | 319 | { |
08678b08 | 320 | struct irq_desc *desc = irq_to_desc(irq); |
2db87321 UKK |
321 | int ret = -ENXIO; |
322 | ||
323 | if (desc->chip->set_wake) | |
324 | ret = desc->chip->set_wake(irq, on); | |
325 | ||
326 | return ret; | |
327 | } | |
328 | ||
ba9a2331 TG |
329 | /** |
330 | * set_irq_wake - control irq power management wakeup | |
331 | * @irq: interrupt to control | |
332 | * @on: enable/disable power management wakeup | |
333 | * | |
15a647eb DB |
334 | * Enable/disable power management wakeup mode, which is |
335 | * disabled by default. Enables and disables must match, | |
336 | * just as they match for non-wakeup mode support. | |
337 | * | |
338 | * Wakeup mode lets this IRQ wake the system from sleep | |
339 | * states like "suspend to RAM". | |
ba9a2331 TG |
340 | */ |
341 | int set_irq_wake(unsigned int irq, unsigned int on) | |
342 | { | |
08678b08 | 343 | struct irq_desc *desc = irq_to_desc(irq); |
ba9a2331 | 344 | unsigned long flags; |
2db87321 | 345 | int ret = 0; |
ba9a2331 | 346 | |
15a647eb DB |
347 | /* wakeup-capable irqs can be shared between drivers that |
348 | * don't need to have the same sleep mode behaviors. | |
349 | */ | |
ba9a2331 | 350 | spin_lock_irqsave(&desc->lock, flags); |
15a647eb | 351 | if (on) { |
2db87321 UKK |
352 | if (desc->wake_depth++ == 0) { |
353 | ret = set_irq_wake_real(irq, on); | |
354 | if (ret) | |
355 | desc->wake_depth = 0; | |
356 | else | |
357 | desc->status |= IRQ_WAKEUP; | |
358 | } | |
15a647eb DB |
359 | } else { |
360 | if (desc->wake_depth == 0) { | |
7a2c4770 | 361 | WARN(1, "Unbalanced IRQ %d wake disable\n", irq); |
2db87321 UKK |
362 | } else if (--desc->wake_depth == 0) { |
363 | ret = set_irq_wake_real(irq, on); | |
364 | if (ret) | |
365 | desc->wake_depth = 1; | |
366 | else | |
367 | desc->status &= ~IRQ_WAKEUP; | |
368 | } | |
15a647eb | 369 | } |
2db87321 | 370 | |
ba9a2331 TG |
371 | spin_unlock_irqrestore(&desc->lock, flags); |
372 | return ret; | |
373 | } | |
374 | EXPORT_SYMBOL(set_irq_wake); | |
375 | ||
1da177e4 LT |
376 | /* |
377 | * Internal function that tells the architecture code whether a | |
378 | * particular irq has been exclusively allocated or is available | |
379 | * for driver use. | |
380 | */ | |
381 | int can_request_irq(unsigned int irq, unsigned long irqflags) | |
382 | { | |
d3c60047 | 383 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 LT |
384 | struct irqaction *action; |
385 | ||
7d94f7ca YL |
386 | if (!desc) |
387 | return 0; | |
388 | ||
389 | if (desc->status & IRQ_NOREQUEST) | |
1da177e4 LT |
390 | return 0; |
391 | ||
08678b08 | 392 | action = desc->action; |
1da177e4 | 393 | if (action) |
3cca53b0 | 394 | if (irqflags & action->flags & IRQF_SHARED) |
1da177e4 LT |
395 | action = NULL; |
396 | ||
397 | return !action; | |
398 | } | |
399 | ||
6a6de9ef TG |
400 | void compat_irq_chip_set_default_handler(struct irq_desc *desc) |
401 | { | |
402 | /* | |
403 | * If the architecture still has not overriden | |
404 | * the flow handler then zap the default. This | |
405 | * should catch incorrect flow-type setting. | |
406 | */ | |
407 | if (desc->handle_irq == &handle_bad_irq) | |
408 | desc->handle_irq = NULL; | |
409 | } | |
410 | ||
0c5d1eb7 | 411 | int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, |
82736f4d UKK |
412 | unsigned long flags) |
413 | { | |
414 | int ret; | |
0c5d1eb7 | 415 | struct irq_chip *chip = desc->chip; |
82736f4d UKK |
416 | |
417 | if (!chip || !chip->set_type) { | |
418 | /* | |
419 | * IRQF_TRIGGER_* but the PIC does not support multiple | |
420 | * flow-types? | |
421 | */ | |
3ff68a6a | 422 | pr_debug("No set_type function for IRQ %d (%s)\n", irq, |
82736f4d UKK |
423 | chip ? (chip->name ? : "unknown") : "unknown"); |
424 | return 0; | |
425 | } | |
426 | ||
f2b662da DB |
427 | /* caller masked out all except trigger mode flags */ |
428 | ret = chip->set_type(irq, flags); | |
82736f4d UKK |
429 | |
430 | if (ret) | |
c69ad71b | 431 | pr_err("setting trigger mode %d for irq %u failed (%pF)\n", |
f2b662da | 432 | (int)flags, irq, chip->set_type); |
0c5d1eb7 | 433 | else { |
f2b662da DB |
434 | if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) |
435 | flags |= IRQ_LEVEL; | |
0c5d1eb7 | 436 | /* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */ |
f2b662da DB |
437 | desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK); |
438 | desc->status |= flags; | |
0c5d1eb7 | 439 | } |
82736f4d UKK |
440 | |
441 | return ret; | |
442 | } | |
443 | ||
b25c340c TG |
444 | /* |
445 | * Default primary interrupt handler for threaded interrupts. Is | |
446 | * assigned as primary handler when request_threaded_irq is called | |
447 | * with handler == NULL. Useful for oneshot interrupts. | |
448 | */ | |
449 | static irqreturn_t irq_default_primary_handler(int irq, void *dev_id) | |
450 | { | |
451 | return IRQ_WAKE_THREAD; | |
452 | } | |
453 | ||
399b5da2 TG |
454 | /* |
455 | * Primary handler for nested threaded interrupts. Should never be | |
456 | * called. | |
457 | */ | |
458 | static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) | |
459 | { | |
460 | WARN(1, "Primary handler called for nested irq %d\n", irq); | |
461 | return IRQ_NONE; | |
462 | } | |
463 | ||
3aa551c9 TG |
464 | static int irq_wait_for_interrupt(struct irqaction *action) |
465 | { | |
466 | while (!kthread_should_stop()) { | |
467 | set_current_state(TASK_INTERRUPTIBLE); | |
f48fe81e TG |
468 | |
469 | if (test_and_clear_bit(IRQTF_RUNTHREAD, | |
470 | &action->thread_flags)) { | |
3aa551c9 TG |
471 | __set_current_state(TASK_RUNNING); |
472 | return 0; | |
f48fe81e TG |
473 | } |
474 | schedule(); | |
3aa551c9 TG |
475 | } |
476 | return -1; | |
477 | } | |
478 | ||
b25c340c TG |
479 | /* |
480 | * Oneshot interrupts keep the irq line masked until the threaded | |
481 | * handler finished. unmask if the interrupt has not been disabled and | |
482 | * is marked MASKED. | |
483 | */ | |
484 | static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc) | |
485 | { | |
70aedd24 | 486 | chip_bus_lock(irq, desc); |
b25c340c TG |
487 | spin_lock_irq(&desc->lock); |
488 | if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) { | |
489 | desc->status &= ~IRQ_MASKED; | |
490 | desc->chip->unmask(irq); | |
491 | } | |
492 | spin_unlock_irq(&desc->lock); | |
70aedd24 | 493 | chip_bus_sync_unlock(irq, desc); |
b25c340c TG |
494 | } |
495 | ||
61f38261 | 496 | #ifdef CONFIG_SMP |
591d2fb0 TG |
497 | /* |
498 | * Check whether we need to change the affinity of the interrupt thread. | |
499 | */ | |
500 | static void | |
501 | irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) | |
502 | { | |
503 | cpumask_var_t mask; | |
504 | ||
505 | if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags)) | |
506 | return; | |
507 | ||
508 | /* | |
509 | * In case we are out of memory we set IRQTF_AFFINITY again and | |
510 | * try again next time | |
511 | */ | |
512 | if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { | |
513 | set_bit(IRQTF_AFFINITY, &action->thread_flags); | |
514 | return; | |
515 | } | |
516 | ||
517 | spin_lock_irq(&desc->lock); | |
518 | cpumask_copy(mask, desc->affinity); | |
519 | spin_unlock_irq(&desc->lock); | |
520 | ||
521 | set_cpus_allowed_ptr(current, mask); | |
522 | free_cpumask_var(mask); | |
523 | } | |
61f38261 BP |
524 | #else |
525 | static inline void | |
526 | irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { } | |
527 | #endif | |
591d2fb0 | 528 | |
3aa551c9 TG |
529 | /* |
530 | * Interrupt handler thread | |
531 | */ | |
532 | static int irq_thread(void *data) | |
533 | { | |
534 | struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO/2, }; | |
535 | struct irqaction *action = data; | |
536 | struct irq_desc *desc = irq_to_desc(action->irq); | |
b25c340c | 537 | int wake, oneshot = desc->status & IRQ_ONESHOT; |
3aa551c9 TG |
538 | |
539 | sched_setscheduler(current, SCHED_FIFO, ¶m); | |
540 | current->irqaction = action; | |
541 | ||
542 | while (!irq_wait_for_interrupt(action)) { | |
543 | ||
591d2fb0 TG |
544 | irq_thread_check_affinity(desc, action); |
545 | ||
3aa551c9 TG |
546 | atomic_inc(&desc->threads_active); |
547 | ||
548 | spin_lock_irq(&desc->lock); | |
549 | if (unlikely(desc->status & IRQ_DISABLED)) { | |
550 | /* | |
551 | * CHECKME: We might need a dedicated | |
552 | * IRQ_THREAD_PENDING flag here, which | |
553 | * retriggers the thread in check_irq_resend() | |
554 | * but AFAICT IRQ_PENDING should be fine as it | |
555 | * retriggers the interrupt itself --- tglx | |
556 | */ | |
557 | desc->status |= IRQ_PENDING; | |
558 | spin_unlock_irq(&desc->lock); | |
559 | } else { | |
560 | spin_unlock_irq(&desc->lock); | |
561 | ||
562 | action->thread_fn(action->irq, action->dev_id); | |
b25c340c TG |
563 | |
564 | if (oneshot) | |
565 | irq_finalize_oneshot(action->irq, desc); | |
3aa551c9 TG |
566 | } |
567 | ||
568 | wake = atomic_dec_and_test(&desc->threads_active); | |
569 | ||
570 | if (wake && waitqueue_active(&desc->wait_for_threads)) | |
571 | wake_up(&desc->wait_for_threads); | |
572 | } | |
573 | ||
574 | /* | |
575 | * Clear irqaction. Otherwise exit_irq_thread() would make | |
576 | * fuzz about an active irq thread going into nirvana. | |
577 | */ | |
578 | current->irqaction = NULL; | |
579 | return 0; | |
580 | } | |
581 | ||
582 | /* | |
583 | * Called from do_exit() | |
584 | */ | |
585 | void exit_irq_thread(void) | |
586 | { | |
587 | struct task_struct *tsk = current; | |
588 | ||
589 | if (!tsk->irqaction) | |
590 | return; | |
591 | ||
592 | printk(KERN_ERR | |
593 | "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n", | |
594 | tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq); | |
595 | ||
596 | /* | |
597 | * Set the THREAD DIED flag to prevent further wakeups of the | |
598 | * soon to be gone threaded handler. | |
599 | */ | |
600 | set_bit(IRQTF_DIED, &tsk->irqaction->flags); | |
601 | } | |
602 | ||
1da177e4 LT |
603 | /* |
604 | * Internal function to register an irqaction - typically used to | |
605 | * allocate special interrupts that are part of the architecture. | |
606 | */ | |
d3c60047 | 607 | static int |
327ec569 | 608 | __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) |
1da177e4 | 609 | { |
f17c7545 | 610 | struct irqaction *old, **old_ptr; |
8b126b77 | 611 | const char *old_name = NULL; |
1da177e4 | 612 | unsigned long flags; |
399b5da2 | 613 | int nested, shared = 0; |
82736f4d | 614 | int ret; |
1da177e4 | 615 | |
7d94f7ca | 616 | if (!desc) |
c2b5a251 MW |
617 | return -EINVAL; |
618 | ||
f1c2662c | 619 | if (desc->chip == &no_irq_chip) |
1da177e4 LT |
620 | return -ENOSYS; |
621 | /* | |
622 | * Some drivers like serial.c use request_irq() heavily, | |
623 | * so we have to be careful not to interfere with a | |
624 | * running system. | |
625 | */ | |
3cca53b0 | 626 | if (new->flags & IRQF_SAMPLE_RANDOM) { |
1da177e4 LT |
627 | /* |
628 | * This function might sleep, we want to call it first, | |
629 | * outside of the atomic block. | |
630 | * Yes, this might clear the entropy pool if the wrong | |
631 | * driver is attempted to be loaded, without actually | |
632 | * installing a new handler, but is this really a problem, | |
633 | * only the sysadmin is able to do this. | |
634 | */ | |
635 | rand_initialize_irq(irq); | |
636 | } | |
637 | ||
b25c340c TG |
638 | /* Oneshot interrupts are not allowed with shared */ |
639 | if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED)) | |
640 | return -EINVAL; | |
641 | ||
3aa551c9 | 642 | /* |
399b5da2 TG |
643 | * Check whether the interrupt nests into another interrupt |
644 | * thread. | |
645 | */ | |
646 | nested = desc->status & IRQ_NESTED_THREAD; | |
647 | if (nested) { | |
648 | if (!new->thread_fn) | |
649 | return -EINVAL; | |
650 | /* | |
651 | * Replace the primary handler which was provided from | |
652 | * the driver for non nested interrupt handling by the | |
653 | * dummy function which warns when called. | |
654 | */ | |
655 | new->handler = irq_nested_primary_handler; | |
656 | } | |
657 | ||
3aa551c9 | 658 | /* |
399b5da2 TG |
659 | * Create a handler thread when a thread function is supplied |
660 | * and the interrupt does not nest into another interrupt | |
661 | * thread. | |
3aa551c9 | 662 | */ |
399b5da2 | 663 | if (new->thread_fn && !nested) { |
3aa551c9 TG |
664 | struct task_struct *t; |
665 | ||
666 | t = kthread_create(irq_thread, new, "irq/%d-%s", irq, | |
667 | new->name); | |
668 | if (IS_ERR(t)) | |
669 | return PTR_ERR(t); | |
670 | /* | |
671 | * We keep the reference to the task struct even if | |
672 | * the thread dies to avoid that the interrupt code | |
673 | * references an already freed task_struct. | |
674 | */ | |
675 | get_task_struct(t); | |
676 | new->thread = t; | |
3aa551c9 TG |
677 | } |
678 | ||
1da177e4 LT |
679 | /* |
680 | * The following block of code has to be executed atomically | |
681 | */ | |
06fcb0c6 | 682 | spin_lock_irqsave(&desc->lock, flags); |
f17c7545 IM |
683 | old_ptr = &desc->action; |
684 | old = *old_ptr; | |
06fcb0c6 | 685 | if (old) { |
e76de9f8 TG |
686 | /* |
687 | * Can't share interrupts unless both agree to and are | |
688 | * the same type (level, edge, polarity). So both flag | |
3cca53b0 | 689 | * fields must have IRQF_SHARED set and the bits which |
e76de9f8 TG |
690 | * set the trigger type must match. |
691 | */ | |
3cca53b0 | 692 | if (!((old->flags & new->flags) & IRQF_SHARED) || |
8b126b77 AM |
693 | ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) { |
694 | old_name = old->name; | |
f5163427 | 695 | goto mismatch; |
8b126b77 | 696 | } |
f5163427 | 697 | |
284c6680 | 698 | #if defined(CONFIG_IRQ_PER_CPU) |
f5163427 | 699 | /* All handlers must agree on per-cpuness */ |
3cca53b0 TG |
700 | if ((old->flags & IRQF_PERCPU) != |
701 | (new->flags & IRQF_PERCPU)) | |
f5163427 DS |
702 | goto mismatch; |
703 | #endif | |
1da177e4 LT |
704 | |
705 | /* add new interrupt at end of irq queue */ | |
706 | do { | |
f17c7545 IM |
707 | old_ptr = &old->next; |
708 | old = *old_ptr; | |
1da177e4 LT |
709 | } while (old); |
710 | shared = 1; | |
711 | } | |
712 | ||
1da177e4 | 713 | if (!shared) { |
6a6de9ef | 714 | irq_chip_set_defaults(desc->chip); |
e76de9f8 | 715 | |
3aa551c9 TG |
716 | init_waitqueue_head(&desc->wait_for_threads); |
717 | ||
e76de9f8 | 718 | /* Setup the type (level, edge polarity) if configured: */ |
3cca53b0 | 719 | if (new->flags & IRQF_TRIGGER_MASK) { |
f2b662da DB |
720 | ret = __irq_set_trigger(desc, irq, |
721 | new->flags & IRQF_TRIGGER_MASK); | |
82736f4d | 722 | |
3aa551c9 TG |
723 | if (ret) |
724 | goto out_thread; | |
e76de9f8 TG |
725 | } else |
726 | compat_irq_chip_set_default_handler(desc); | |
82736f4d UKK |
727 | #if defined(CONFIG_IRQ_PER_CPU) |
728 | if (new->flags & IRQF_PERCPU) | |
729 | desc->status |= IRQ_PER_CPU; | |
730 | #endif | |
6a6de9ef | 731 | |
b25c340c | 732 | desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT | |
1adb0850 | 733 | IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED); |
94d39e1f | 734 | |
b25c340c TG |
735 | if (new->flags & IRQF_ONESHOT) |
736 | desc->status |= IRQ_ONESHOT; | |
737 | ||
94d39e1f TG |
738 | if (!(desc->status & IRQ_NOAUTOEN)) { |
739 | desc->depth = 0; | |
740 | desc->status &= ~IRQ_DISABLED; | |
7e6e178a | 741 | desc->chip->startup(irq); |
e76de9f8 TG |
742 | } else |
743 | /* Undo nested disables: */ | |
744 | desc->depth = 1; | |
18404756 | 745 | |
612e3684 TG |
746 | /* Exclude IRQ from balancing if requested */ |
747 | if (new->flags & IRQF_NOBALANCING) | |
748 | desc->status |= IRQ_NO_BALANCING; | |
749 | ||
18404756 | 750 | /* Set default affinity mask once everything is setup */ |
548c8933 | 751 | setup_affinity(irq, desc); |
0c5d1eb7 DB |
752 | |
753 | } else if ((new->flags & IRQF_TRIGGER_MASK) | |
754 | && (new->flags & IRQF_TRIGGER_MASK) | |
755 | != (desc->status & IRQ_TYPE_SENSE_MASK)) { | |
756 | /* hope the handler works with the actual trigger mode... */ | |
757 | pr_warning("IRQ %d uses trigger mode %d; requested %d\n", | |
758 | irq, (int)(desc->status & IRQ_TYPE_SENSE_MASK), | |
759 | (int)(new->flags & IRQF_TRIGGER_MASK)); | |
1da177e4 | 760 | } |
82736f4d | 761 | |
69ab8494 | 762 | new->irq = irq; |
f17c7545 | 763 | *old_ptr = new; |
82736f4d | 764 | |
8528b0f1 LT |
765 | /* Reset broken irq detection when installing new handler */ |
766 | desc->irq_count = 0; | |
767 | desc->irqs_unhandled = 0; | |
1adb0850 TG |
768 | |
769 | /* | |
770 | * Check whether we disabled the irq via the spurious handler | |
771 | * before. Reenable it and give it another chance. | |
772 | */ | |
773 | if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) { | |
774 | desc->status &= ~IRQ_SPURIOUS_DISABLED; | |
0a0c5168 | 775 | __enable_irq(desc, irq, false); |
1adb0850 TG |
776 | } |
777 | ||
06fcb0c6 | 778 | spin_unlock_irqrestore(&desc->lock, flags); |
1da177e4 | 779 | |
69ab8494 TG |
780 | /* |
781 | * Strictly no need to wake it up, but hung_task complains | |
782 | * when no hard interrupt wakes the thread up. | |
783 | */ | |
784 | if (new->thread) | |
785 | wake_up_process(new->thread); | |
786 | ||
2c6927a3 | 787 | register_irq_proc(irq, desc); |
1da177e4 LT |
788 | new->dir = NULL; |
789 | register_handler_proc(irq, new); | |
790 | ||
791 | return 0; | |
f5163427 DS |
792 | |
793 | mismatch: | |
3f050447 | 794 | #ifdef CONFIG_DEBUG_SHIRQ |
3cca53b0 | 795 | if (!(new->flags & IRQF_PROBE_SHARED)) { |
e8c4b9d0 | 796 | printk(KERN_ERR "IRQ handler type mismatch for IRQ %d\n", irq); |
8b126b77 AM |
797 | if (old_name) |
798 | printk(KERN_ERR "current handler: %s\n", old_name); | |
13e87ec6 AM |
799 | dump_stack(); |
800 | } | |
3f050447 | 801 | #endif |
3aa551c9 TG |
802 | ret = -EBUSY; |
803 | ||
804 | out_thread: | |
8b126b77 | 805 | spin_unlock_irqrestore(&desc->lock, flags); |
3aa551c9 TG |
806 | if (new->thread) { |
807 | struct task_struct *t = new->thread; | |
808 | ||
809 | new->thread = NULL; | |
810 | if (likely(!test_bit(IRQTF_DIED, &new->thread_flags))) | |
811 | kthread_stop(t); | |
812 | put_task_struct(t); | |
813 | } | |
814 | return ret; | |
1da177e4 LT |
815 | } |
816 | ||
d3c60047 TG |
817 | /** |
818 | * setup_irq - setup an interrupt | |
819 | * @irq: Interrupt line to setup | |
820 | * @act: irqaction for the interrupt | |
821 | * | |
822 | * Used to statically setup interrupts in the early boot process. | |
823 | */ | |
824 | int setup_irq(unsigned int irq, struct irqaction *act) | |
825 | { | |
826 | struct irq_desc *desc = irq_to_desc(irq); | |
827 | ||
828 | return __setup_irq(irq, desc, act); | |
829 | } | |
eb53b4e8 | 830 | EXPORT_SYMBOL_GPL(setup_irq); |
d3c60047 | 831 | |
cbf94f06 MD |
832 | /* |
833 | * Internal function to unregister an irqaction - used to free | |
834 | * regular and special interrupts that are part of the architecture. | |
1da177e4 | 835 | */ |
cbf94f06 | 836 | static struct irqaction *__free_irq(unsigned int irq, void *dev_id) |
1da177e4 | 837 | { |
d3c60047 | 838 | struct irq_desc *desc = irq_to_desc(irq); |
f17c7545 | 839 | struct irqaction *action, **action_ptr; |
1da177e4 LT |
840 | unsigned long flags; |
841 | ||
ae88a23b | 842 | WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq); |
7d94f7ca | 843 | |
7d94f7ca | 844 | if (!desc) |
f21cfb25 | 845 | return NULL; |
1da177e4 | 846 | |
06fcb0c6 | 847 | spin_lock_irqsave(&desc->lock, flags); |
ae88a23b IM |
848 | |
849 | /* | |
850 | * There can be multiple actions per IRQ descriptor, find the right | |
851 | * one based on the dev_id: | |
852 | */ | |
f17c7545 | 853 | action_ptr = &desc->action; |
1da177e4 | 854 | for (;;) { |
f17c7545 | 855 | action = *action_ptr; |
1da177e4 | 856 | |
ae88a23b IM |
857 | if (!action) { |
858 | WARN(1, "Trying to free already-free IRQ %d\n", irq); | |
859 | spin_unlock_irqrestore(&desc->lock, flags); | |
1da177e4 | 860 | |
f21cfb25 | 861 | return NULL; |
ae88a23b | 862 | } |
1da177e4 | 863 | |
8316e381 IM |
864 | if (action->dev_id == dev_id) |
865 | break; | |
f17c7545 | 866 | action_ptr = &action->next; |
ae88a23b | 867 | } |
dbce706e | 868 | |
ae88a23b | 869 | /* Found it - now remove it from the list of entries: */ |
f17c7545 | 870 | *action_ptr = action->next; |
ae88a23b IM |
871 | |
872 | /* Currently used only by UML, might disappear one day: */ | |
b77d6adc | 873 | #ifdef CONFIG_IRQ_RELEASE_METHOD |
ae88a23b IM |
874 | if (desc->chip->release) |
875 | desc->chip->release(irq, dev_id); | |
b77d6adc | 876 | #endif |
dbce706e | 877 | |
ae88a23b IM |
878 | /* If this was the last handler, shut down the IRQ line: */ |
879 | if (!desc->action) { | |
880 | desc->status |= IRQ_DISABLED; | |
881 | if (desc->chip->shutdown) | |
882 | desc->chip->shutdown(irq); | |
883 | else | |
884 | desc->chip->disable(irq); | |
885 | } | |
3aa551c9 | 886 | |
ae88a23b IM |
887 | spin_unlock_irqrestore(&desc->lock, flags); |
888 | ||
889 | unregister_handler_proc(irq, action); | |
890 | ||
891 | /* Make sure it's not being used on another CPU: */ | |
892 | synchronize_irq(irq); | |
1da177e4 | 893 | |
70edcd77 | 894 | #ifdef CONFIG_DEBUG_SHIRQ |
ae88a23b IM |
895 | /* |
896 | * It's a shared IRQ -- the driver ought to be prepared for an IRQ | |
897 | * event to happen even now it's being freed, so let's make sure that | |
898 | * is so by doing an extra call to the handler .... | |
899 | * | |
900 | * ( We do this after actually deregistering it, to make sure that a | |
901 | * 'real' IRQ doesn't run in * parallel with our fake. ) | |
902 | */ | |
903 | if (action->flags & IRQF_SHARED) { | |
904 | local_irq_save(flags); | |
905 | action->handler(irq, dev_id); | |
906 | local_irq_restore(flags); | |
1da177e4 | 907 | } |
ae88a23b | 908 | #endif |
2d860ad7 LT |
909 | |
910 | if (action->thread) { | |
911 | if (!test_bit(IRQTF_DIED, &action->thread_flags)) | |
912 | kthread_stop(action->thread); | |
913 | put_task_struct(action->thread); | |
914 | } | |
915 | ||
f21cfb25 MD |
916 | return action; |
917 | } | |
918 | ||
cbf94f06 MD |
919 | /** |
920 | * remove_irq - free an interrupt | |
921 | * @irq: Interrupt line to free | |
922 | * @act: irqaction for the interrupt | |
923 | * | |
924 | * Used to remove interrupts statically setup by the early boot process. | |
925 | */ | |
926 | void remove_irq(unsigned int irq, struct irqaction *act) | |
927 | { | |
928 | __free_irq(irq, act->dev_id); | |
929 | } | |
eb53b4e8 | 930 | EXPORT_SYMBOL_GPL(remove_irq); |
cbf94f06 | 931 | |
f21cfb25 MD |
932 | /** |
933 | * free_irq - free an interrupt allocated with request_irq | |
934 | * @irq: Interrupt line to free | |
935 | * @dev_id: Device identity to free | |
936 | * | |
937 | * Remove an interrupt handler. The handler is removed and if the | |
938 | * interrupt line is no longer in use by any driver it is disabled. | |
939 | * On a shared IRQ the caller must ensure the interrupt is disabled | |
940 | * on the card it drives before calling this function. The function | |
941 | * does not return until any executing interrupts for this IRQ | |
942 | * have completed. | |
943 | * | |
944 | * This function must not be called from interrupt context. | |
945 | */ | |
946 | void free_irq(unsigned int irq, void *dev_id) | |
947 | { | |
70aedd24 TG |
948 | struct irq_desc *desc = irq_to_desc(irq); |
949 | ||
950 | if (!desc) | |
951 | return; | |
952 | ||
953 | chip_bus_lock(irq, desc); | |
cbf94f06 | 954 | kfree(__free_irq(irq, dev_id)); |
70aedd24 | 955 | chip_bus_sync_unlock(irq, desc); |
1da177e4 | 956 | } |
1da177e4 LT |
957 | EXPORT_SYMBOL(free_irq); |
958 | ||
959 | /** | |
3aa551c9 | 960 | * request_threaded_irq - allocate an interrupt line |
1da177e4 | 961 | * @irq: Interrupt line to allocate |
3aa551c9 TG |
962 | * @handler: Function to be called when the IRQ occurs. |
963 | * Primary handler for threaded interrupts | |
b25c340c TG |
964 | * If NULL and thread_fn != NULL the default |
965 | * primary handler is installed | |
f48fe81e TG |
966 | * @thread_fn: Function called from the irq handler thread |
967 | * If NULL, no irq thread is created | |
1da177e4 LT |
968 | * @irqflags: Interrupt type flags |
969 | * @devname: An ascii name for the claiming device | |
970 | * @dev_id: A cookie passed back to the handler function | |
971 | * | |
972 | * This call allocates interrupt resources and enables the | |
973 | * interrupt line and IRQ handling. From the point this | |
974 | * call is made your handler function may be invoked. Since | |
975 | * your handler function must clear any interrupt the board | |
976 | * raises, you must take care both to initialise your hardware | |
977 | * and to set up the interrupt handler in the right order. | |
978 | * | |
3aa551c9 TG |
979 | * If you want to set up a threaded irq handler for your device |
980 | * then you need to supply @handler and @thread_fn. @handler ist | |
981 | * still called in hard interrupt context and has to check | |
982 | * whether the interrupt originates from the device. If yes it | |
983 | * needs to disable the interrupt on the device and return | |
39a2eddb | 984 | * IRQ_WAKE_THREAD which will wake up the handler thread and run |
3aa551c9 TG |
985 | * @thread_fn. This split handler design is necessary to support |
986 | * shared interrupts. | |
987 | * | |
1da177e4 LT |
988 | * Dev_id must be globally unique. Normally the address of the |
989 | * device data structure is used as the cookie. Since the handler | |
990 | * receives this value it makes sense to use it. | |
991 | * | |
992 | * If your interrupt is shared you must pass a non NULL dev_id | |
993 | * as this is required when freeing the interrupt. | |
994 | * | |
995 | * Flags: | |
996 | * | |
3cca53b0 TG |
997 | * IRQF_SHARED Interrupt is shared |
998 | * IRQF_DISABLED Disable local interrupts while processing | |
999 | * IRQF_SAMPLE_RANDOM The interrupt can be used for entropy | |
0c5d1eb7 | 1000 | * IRQF_TRIGGER_* Specify active edge(s) or level |
1da177e4 LT |
1001 | * |
1002 | */ | |
3aa551c9 TG |
1003 | int request_threaded_irq(unsigned int irq, irq_handler_t handler, |
1004 | irq_handler_t thread_fn, unsigned long irqflags, | |
1005 | const char *devname, void *dev_id) | |
1da177e4 | 1006 | { |
06fcb0c6 | 1007 | struct irqaction *action; |
08678b08 | 1008 | struct irq_desc *desc; |
d3c60047 | 1009 | int retval; |
1da177e4 | 1010 | |
470c6623 DB |
1011 | /* |
1012 | * handle_IRQ_event() always ignores IRQF_DISABLED except for | |
1013 | * the _first_ irqaction (sigh). That can cause oopsing, but | |
1014 | * the behavior is classified as "will not fix" so we need to | |
1015 | * start nudging drivers away from using that idiom. | |
1016 | */ | |
327ec569 IM |
1017 | if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) == |
1018 | (IRQF_SHARED|IRQF_DISABLED)) { | |
1019 | pr_warning( | |
1020 | "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n", | |
1021 | irq, devname); | |
1022 | } | |
470c6623 | 1023 | |
fbb9ce95 IM |
1024 | #ifdef CONFIG_LOCKDEP |
1025 | /* | |
1026 | * Lockdep wants atomic interrupt handlers: | |
1027 | */ | |
38515e90 | 1028 | irqflags |= IRQF_DISABLED; |
fbb9ce95 | 1029 | #endif |
1da177e4 LT |
1030 | /* |
1031 | * Sanity-check: shared interrupts must pass in a real dev-ID, | |
1032 | * otherwise we'll have trouble later trying to figure out | |
1033 | * which interrupt is which (messes up the interrupt freeing | |
1034 | * logic etc). | |
1035 | */ | |
3cca53b0 | 1036 | if ((irqflags & IRQF_SHARED) && !dev_id) |
1da177e4 | 1037 | return -EINVAL; |
7d94f7ca | 1038 | |
cb5bc832 | 1039 | desc = irq_to_desc(irq); |
7d94f7ca | 1040 | if (!desc) |
1da177e4 | 1041 | return -EINVAL; |
7d94f7ca | 1042 | |
08678b08 | 1043 | if (desc->status & IRQ_NOREQUEST) |
6550c775 | 1044 | return -EINVAL; |
b25c340c TG |
1045 | |
1046 | if (!handler) { | |
1047 | if (!thread_fn) | |
1048 | return -EINVAL; | |
1049 | handler = irq_default_primary_handler; | |
1050 | } | |
1da177e4 | 1051 | |
45535732 | 1052 | action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); |
1da177e4 LT |
1053 | if (!action) |
1054 | return -ENOMEM; | |
1055 | ||
1056 | action->handler = handler; | |
3aa551c9 | 1057 | action->thread_fn = thread_fn; |
1da177e4 | 1058 | action->flags = irqflags; |
1da177e4 | 1059 | action->name = devname; |
1da177e4 LT |
1060 | action->dev_id = dev_id; |
1061 | ||
70aedd24 | 1062 | chip_bus_lock(irq, desc); |
d3c60047 | 1063 | retval = __setup_irq(irq, desc, action); |
70aedd24 TG |
1064 | chip_bus_sync_unlock(irq, desc); |
1065 | ||
377bf1e4 AV |
1066 | if (retval) |
1067 | kfree(action); | |
1068 | ||
a304e1b8 | 1069 | #ifdef CONFIG_DEBUG_SHIRQ |
6ce51c43 | 1070 | if (!retval && (irqflags & IRQF_SHARED)) { |
a304e1b8 DW |
1071 | /* |
1072 | * It's a shared IRQ -- the driver ought to be prepared for it | |
1073 | * to happen immediately, so let's make sure.... | |
377bf1e4 AV |
1074 | * We disable the irq to make sure that a 'real' IRQ doesn't |
1075 | * run in parallel with our fake. | |
a304e1b8 | 1076 | */ |
59845b1f | 1077 | unsigned long flags; |
a304e1b8 | 1078 | |
377bf1e4 | 1079 | disable_irq(irq); |
59845b1f | 1080 | local_irq_save(flags); |
377bf1e4 | 1081 | |
59845b1f | 1082 | handler(irq, dev_id); |
377bf1e4 | 1083 | |
59845b1f | 1084 | local_irq_restore(flags); |
377bf1e4 | 1085 | enable_irq(irq); |
a304e1b8 DW |
1086 | } |
1087 | #endif | |
1da177e4 LT |
1088 | return retval; |
1089 | } | |
3aa551c9 | 1090 | EXPORT_SYMBOL(request_threaded_irq); |