ps3av: add quirk database for broken monitors
[wrt350n-kernel.git] / kernel / irq / chip.c
blobf1a73f0b54e775d29a9e2184d3d13cfae75af239
1 /*
2 * linux/kernel/irq/chip.c
4 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
5 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
7 * This file contains the core interrupt handling code, for irq-chip
8 * based architectures.
10 * Detailed information is available in Documentation/DocBook/genericirq
13 #include <linux/irq.h>
14 #include <linux/msi.h>
15 #include <linux/module.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h>
19 #include "internals.h"
21 /**
22 * dynamic_irq_init - initialize a dynamically allocated irq
23 * @irq: irq number to initialize
25 void dynamic_irq_init(unsigned int irq)
27 struct irq_desc *desc;
28 unsigned long flags;
30 if (irq >= NR_IRQS) {
31 printk(KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
32 WARN_ON(1);
33 return;
36 /* Ensure we don't have left over values from a previous use of this irq */
37 desc = irq_desc + irq;
38 spin_lock_irqsave(&desc->lock, flags);
39 desc->status = IRQ_DISABLED;
40 desc->chip = &no_irq_chip;
41 desc->handle_irq = handle_bad_irq;
42 desc->depth = 1;
43 desc->msi_desc = NULL;
44 desc->handler_data = NULL;
45 desc->chip_data = NULL;
46 desc->action = NULL;
47 desc->irq_count = 0;
48 desc->irqs_unhandled = 0;
49 #ifdef CONFIG_SMP
50 desc->affinity = CPU_MASK_ALL;
51 #endif
52 spin_unlock_irqrestore(&desc->lock, flags);
55 /**
56 * dynamic_irq_cleanup - cleanup a dynamically allocated irq
57 * @irq: irq number to initialize
59 void dynamic_irq_cleanup(unsigned int irq)
61 struct irq_desc *desc;
62 unsigned long flags;
64 if (irq >= NR_IRQS) {
65 printk(KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
66 WARN_ON(1);
67 return;
70 desc = irq_desc + irq;
71 spin_lock_irqsave(&desc->lock, flags);
72 if (desc->action) {
73 spin_unlock_irqrestore(&desc->lock, flags);
74 printk(KERN_ERR "Destroying IRQ%d without calling free_irq\n",
75 irq);
76 WARN_ON(1);
77 return;
79 desc->msi_desc = NULL;
80 desc->handler_data = NULL;
81 desc->chip_data = NULL;
82 desc->handle_irq = handle_bad_irq;
83 desc->chip = &no_irq_chip;
84 spin_unlock_irqrestore(&desc->lock, flags);
88 /**
89 * set_irq_chip - set the irq chip for an irq
90 * @irq: irq number
91 * @chip: pointer to irq chip description structure
93 int set_irq_chip(unsigned int irq, struct irq_chip *chip)
95 struct irq_desc *desc;
96 unsigned long flags;
98 if (irq >= NR_IRQS) {
99 printk(KERN_ERR "Trying to install chip for IRQ%d\n", irq);
100 WARN_ON(1);
101 return -EINVAL;
104 if (!chip)
105 chip = &no_irq_chip;
107 desc = irq_desc + irq;
108 spin_lock_irqsave(&desc->lock, flags);
109 irq_chip_set_defaults(chip);
110 desc->chip = chip;
111 spin_unlock_irqrestore(&desc->lock, flags);
113 return 0;
115 EXPORT_SYMBOL(set_irq_chip);
118 * set_irq_type - set the irq type for an irq
119 * @irq: irq number
120 * @type: interrupt type - see include/linux/interrupt.h
122 int set_irq_type(unsigned int irq, unsigned int type)
124 struct irq_desc *desc;
125 unsigned long flags;
126 int ret = -ENXIO;
128 if (irq >= NR_IRQS) {
129 printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
130 return -ENODEV;
133 desc = irq_desc + irq;
134 if (desc->chip->set_type) {
135 spin_lock_irqsave(&desc->lock, flags);
136 ret = desc->chip->set_type(irq, type);
137 spin_unlock_irqrestore(&desc->lock, flags);
139 return ret;
141 EXPORT_SYMBOL(set_irq_type);
144 * set_irq_data - set irq type data for an irq
145 * @irq: Interrupt number
146 * @data: Pointer to interrupt specific data
148 * Set the hardware irq controller data for an irq
150 int set_irq_data(unsigned int irq, void *data)
152 struct irq_desc *desc;
153 unsigned long flags;
155 if (irq >= NR_IRQS) {
156 printk(KERN_ERR
157 "Trying to install controller data for IRQ%d\n", irq);
158 return -EINVAL;
161 desc = irq_desc + irq;
162 spin_lock_irqsave(&desc->lock, flags);
163 desc->handler_data = data;
164 spin_unlock_irqrestore(&desc->lock, flags);
165 return 0;
167 EXPORT_SYMBOL(set_irq_data);
170 * set_irq_data - set irq type data for an irq
171 * @irq: Interrupt number
172 * @entry: Pointer to MSI descriptor data
174 * Set the hardware irq controller data for an irq
176 int set_irq_msi(unsigned int irq, struct msi_desc *entry)
178 struct irq_desc *desc;
179 unsigned long flags;
181 if (irq >= NR_IRQS) {
182 printk(KERN_ERR
183 "Trying to install msi data for IRQ%d\n", irq);
184 return -EINVAL;
186 desc = irq_desc + irq;
187 spin_lock_irqsave(&desc->lock, flags);
188 desc->msi_desc = entry;
189 if (entry)
190 entry->irq = irq;
191 spin_unlock_irqrestore(&desc->lock, flags);
192 return 0;
196 * set_irq_chip_data - set irq chip data for an irq
197 * @irq: Interrupt number
198 * @data: Pointer to chip specific data
200 * Set the hardware irq chip data for an irq
202 int set_irq_chip_data(unsigned int irq, void *data)
204 struct irq_desc *desc = irq_desc + irq;
205 unsigned long flags;
207 if (irq >= NR_IRQS || !desc->chip) {
208 printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
209 return -EINVAL;
212 spin_lock_irqsave(&desc->lock, flags);
213 desc->chip_data = data;
214 spin_unlock_irqrestore(&desc->lock, flags);
216 return 0;
218 EXPORT_SYMBOL(set_irq_chip_data);
221 * default enable function
223 static void default_enable(unsigned int irq)
225 struct irq_desc *desc = irq_desc + irq;
227 desc->chip->unmask(irq);
228 desc->status &= ~IRQ_MASKED;
232 * default disable function
234 static void default_disable(unsigned int irq)
239 * default startup function
241 static unsigned int default_startup(unsigned int irq)
243 irq_desc[irq].chip->enable(irq);
245 return 0;
249 * Fixup enable/disable function pointers
251 void irq_chip_set_defaults(struct irq_chip *chip)
253 if (!chip->enable)
254 chip->enable = default_enable;
255 if (!chip->disable)
256 chip->disable = default_disable;
257 if (!chip->startup)
258 chip->startup = default_startup;
259 if (!chip->shutdown)
260 chip->shutdown = chip->disable;
261 if (!chip->name)
262 chip->name = chip->typename;
263 if (!chip->end)
264 chip->end = dummy_irq_chip.end;
267 static inline void mask_ack_irq(struct irq_desc *desc, int irq)
269 if (desc->chip->mask_ack)
270 desc->chip->mask_ack(irq);
271 else {
272 desc->chip->mask(irq);
273 desc->chip->ack(irq);
278 * handle_simple_irq - Simple and software-decoded IRQs.
279 * @irq: the interrupt number
280 * @desc: the interrupt description structure for this irq
282 * Simple interrupts are either sent from a demultiplexing interrupt
283 * handler or come from hardware, where no interrupt hardware control
284 * is necessary.
286 * Note: The caller is expected to handle the ack, clear, mask and
287 * unmask issues if necessary.
289 void fastcall
290 handle_simple_irq(unsigned int irq, struct irq_desc *desc)
292 struct irqaction *action;
293 irqreturn_t action_ret;
294 const unsigned int cpu = smp_processor_id();
296 spin_lock(&desc->lock);
298 if (unlikely(desc->status & IRQ_INPROGRESS))
299 goto out_unlock;
300 kstat_cpu(cpu).irqs[irq]++;
302 action = desc->action;
303 if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
304 if (desc->chip->mask)
305 desc->chip->mask(irq);
306 desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
307 desc->status |= IRQ_PENDING;
308 goto out_unlock;
311 desc->status &= ~(IRQ_REPLAY | IRQ_WAITING | IRQ_PENDING);
312 desc->status |= IRQ_INPROGRESS;
313 spin_unlock(&desc->lock);
315 action_ret = handle_IRQ_event(irq, action);
316 if (!noirqdebug)
317 note_interrupt(irq, desc, action_ret);
319 spin_lock(&desc->lock);
320 desc->status &= ~IRQ_INPROGRESS;
321 out_unlock:
322 spin_unlock(&desc->lock);
326 * handle_level_irq - Level type irq handler
327 * @irq: the interrupt number
328 * @desc: the interrupt description structure for this irq
330 * Level type interrupts are active as long as the hardware line has
331 * the active level. This may require to mask the interrupt and unmask
332 * it after the associated handler has acknowledged the device, so the
333 * interrupt line is back to inactive.
335 void fastcall
336 handle_level_irq(unsigned int irq, struct irq_desc *desc)
338 unsigned int cpu = smp_processor_id();
339 struct irqaction *action;
340 irqreturn_t action_ret;
342 spin_lock(&desc->lock);
343 mask_ack_irq(desc, irq);
345 if (unlikely(desc->status & IRQ_INPROGRESS))
346 goto out_unlock;
347 desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
348 kstat_cpu(cpu).irqs[irq]++;
351 * If its disabled or no action available
352 * keep it masked and get out of here
354 action = desc->action;
355 if (unlikely(!action || (desc->status & IRQ_DISABLED)))
356 goto out_unlock;
358 desc->status |= IRQ_INPROGRESS;
359 spin_unlock(&desc->lock);
361 action_ret = handle_IRQ_event(irq, action);
362 if (!noirqdebug)
363 note_interrupt(irq, desc, action_ret);
365 spin_lock(&desc->lock);
366 desc->status &= ~IRQ_INPROGRESS;
367 if (!(desc->status & IRQ_DISABLED) && desc->chip->unmask)
368 desc->chip->unmask(irq);
369 out_unlock:
370 spin_unlock(&desc->lock);
374 * handle_fasteoi_irq - irq handler for transparent controllers
375 * @irq: the interrupt number
376 * @desc: the interrupt description structure for this irq
378 * Only a single callback will be issued to the chip: an ->eoi()
379 * call when the interrupt has been serviced. This enables support
380 * for modern forms of interrupt handlers, which handle the flow
381 * details in hardware, transparently.
383 void fastcall
384 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
386 unsigned int cpu = smp_processor_id();
387 struct irqaction *action;
388 irqreturn_t action_ret;
390 spin_lock(&desc->lock);
392 if (unlikely(desc->status & IRQ_INPROGRESS))
393 goto out;
395 desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
396 kstat_cpu(cpu).irqs[irq]++;
399 * If its disabled or no action available
400 * then mask it and get out of here:
402 action = desc->action;
403 if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
404 desc->status |= IRQ_PENDING;
405 if (desc->chip->mask)
406 desc->chip->mask(irq);
407 goto out;
410 desc->status |= IRQ_INPROGRESS;
411 desc->status &= ~IRQ_PENDING;
412 spin_unlock(&desc->lock);
414 action_ret = handle_IRQ_event(irq, action);
415 if (!noirqdebug)
416 note_interrupt(irq, desc, action_ret);
418 spin_lock(&desc->lock);
419 desc->status &= ~IRQ_INPROGRESS;
420 out:
421 desc->chip->eoi(irq);
423 spin_unlock(&desc->lock);
427 * handle_edge_irq - edge type IRQ handler
428 * @irq: the interrupt number
429 * @desc: the interrupt description structure for this irq
431 * Interrupt occures on the falling and/or rising edge of a hardware
432 * signal. The occurence is latched into the irq controller hardware
433 * and must be acked in order to be reenabled. After the ack another
434 * interrupt can happen on the same source even before the first one
435 * is handled by the assosiacted event handler. If this happens it
436 * might be necessary to disable (mask) the interrupt depending on the
437 * controller hardware. This requires to reenable the interrupt inside
438 * of the loop which handles the interrupts which have arrived while
439 * the handler was running. If all pending interrupts are handled, the
440 * loop is left.
442 void fastcall
443 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
445 const unsigned int cpu = smp_processor_id();
447 spin_lock(&desc->lock);
449 desc->status &= ~(IRQ_REPLAY | IRQ_WAITING);
452 * If we're currently running this IRQ, or its disabled,
453 * we shouldn't process the IRQ. Mark it pending, handle
454 * the necessary masking and go out
456 if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) ||
457 !desc->action)) {
458 desc->status |= (IRQ_PENDING | IRQ_MASKED);
459 mask_ack_irq(desc, irq);
460 goto out_unlock;
463 kstat_cpu(cpu).irqs[irq]++;
465 /* Start handling the irq */
466 desc->chip->ack(irq);
468 /* Mark the IRQ currently in progress.*/
469 desc->status |= IRQ_INPROGRESS;
471 do {
472 struct irqaction *action = desc->action;
473 irqreturn_t action_ret;
475 if (unlikely(!action)) {
476 desc->chip->mask(irq);
477 goto out_unlock;
481 * When another irq arrived while we were handling
482 * one, we could have masked the irq.
483 * Renable it, if it was not disabled in meantime.
485 if (unlikely((desc->status &
486 (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) ==
487 (IRQ_PENDING | IRQ_MASKED))) {
488 desc->chip->unmask(irq);
489 desc->status &= ~IRQ_MASKED;
492 desc->status &= ~IRQ_PENDING;
493 spin_unlock(&desc->lock);
494 action_ret = handle_IRQ_event(irq, action);
495 if (!noirqdebug)
496 note_interrupt(irq, desc, action_ret);
497 spin_lock(&desc->lock);
499 } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);
501 desc->status &= ~IRQ_INPROGRESS;
502 out_unlock:
503 spin_unlock(&desc->lock);
506 #ifdef CONFIG_SMP
508 * handle_percpu_IRQ - Per CPU local irq handler
509 * @irq: the interrupt number
510 * @desc: the interrupt description structure for this irq
512 * Per CPU interrupts on SMP machines without locking requirements
514 void fastcall
515 handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
517 irqreturn_t action_ret;
519 kstat_this_cpu.irqs[irq]++;
521 if (desc->chip->ack)
522 desc->chip->ack(irq);
524 action_ret = handle_IRQ_event(irq, desc->action);
525 if (!noirqdebug)
526 note_interrupt(irq, desc, action_ret);
528 if (desc->chip->eoi)
529 desc->chip->eoi(irq);
532 #endif /* CONFIG_SMP */
534 void
535 __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
536 const char *name)
538 struct irq_desc *desc;
539 unsigned long flags;
541 if (irq >= NR_IRQS) {
542 printk(KERN_ERR
543 "Trying to install type control for IRQ%d\n", irq);
544 return;
547 desc = irq_desc + irq;
549 if (!handle)
550 handle = handle_bad_irq;
551 else if (desc->chip == &no_irq_chip) {
552 printk(KERN_WARNING "Trying to install %sinterrupt handler "
553 "for IRQ%d\n", is_chained ? "chained " : "", irq);
555 * Some ARM implementations install a handler for really dumb
556 * interrupt hardware without setting an irq_chip. This worked
557 * with the ARM no_irq_chip but the check in setup_irq would
558 * prevent us to setup the interrupt at all. Switch it to
559 * dummy_irq_chip for easy transition.
561 desc->chip = &dummy_irq_chip;
564 spin_lock_irqsave(&desc->lock, flags);
566 /* Uninstall? */
567 if (handle == handle_bad_irq) {
568 if (desc->chip != &no_irq_chip)
569 mask_ack_irq(desc, irq);
570 desc->status |= IRQ_DISABLED;
571 desc->depth = 1;
573 desc->handle_irq = handle;
574 desc->name = name;
576 if (handle != handle_bad_irq && is_chained) {
577 desc->status &= ~IRQ_DISABLED;
578 desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
579 desc->depth = 0;
580 desc->chip->unmask(irq);
582 spin_unlock_irqrestore(&desc->lock, flags);
585 void
586 set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
587 irq_flow_handler_t handle)
589 set_irq_chip(irq, chip);
590 __set_irq_handler(irq, handle, 0, NULL);
593 void
594 set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
595 irq_flow_handler_t handle, const char *name)
597 set_irq_chip(irq, chip);
598 __set_irq_handler(irq, handle, 0, name);