Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/irq/pm.c |
| 3 | * |
| 4 | * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
| 5 | * |
| 6 | * This file contains power management functions related to interrupts. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/irq.h> |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/interrupt.h> |
| 12 | |
| 13 | #include "internals.h" |
| 14 | |
| 15 | /** |
| 16 | * suspend_device_irqs - disable all currently enabled interrupt lines |
| 17 | * |
Rafael J. Wysocki | c71320d | 2009-07-05 00:22:34 +0200 | [diff] [blame] | 18 | * During system-wide suspend or hibernation device drivers need to be prevented |
| 19 | * from receiving interrupts and this function is provided for this purpose. |
| 20 | * It marks all interrupt lines in use, except for the timer ones, as disabled |
Thomas Gleixner | c531e83 | 2011-02-08 12:44:58 +0100 | [diff] [blame] | 21 | * and sets the IRQS_SUSPENDED flag for each of them. |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 22 | */ |
| 23 | void suspend_device_irqs(void) |
| 24 | { |
| 25 | struct irq_desc *desc; |
| 26 | int irq; |
| 27 | |
| 28 | for_each_irq_desc(irq, desc) { |
| 29 | unsigned long flags; |
| 30 | |
Thomas Gleixner | 239007b | 2009-11-17 16:46:45 +0100 | [diff] [blame] | 31 | raw_spin_lock_irqsave(&desc->lock, flags); |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 32 | __disable_irq(desc, irq, true); |
Thomas Gleixner | 239007b | 2009-11-17 16:46:45 +0100 | [diff] [blame] | 33 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 34 | } |
| 35 | |
| 36 | for_each_irq_desc(irq, desc) |
Thomas Gleixner | c531e83 | 2011-02-08 12:44:58 +0100 | [diff] [blame] | 37 | if (desc->istate & IRQS_SUSPENDED) |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 38 | synchronize_irq(irq); |
| 39 | } |
| 40 | EXPORT_SYMBOL_GPL(suspend_device_irqs); |
| 41 | |
| 42 | /** |
| 43 | * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs() |
| 44 | * |
| 45 | * Enable all interrupt lines previously disabled by suspend_device_irqs() that |
Thomas Gleixner | c531e83 | 2011-02-08 12:44:58 +0100 | [diff] [blame] | 46 | * have the IRQS_SUSPENDED flag set. |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 47 | */ |
| 48 | void resume_device_irqs(void) |
| 49 | { |
| 50 | struct irq_desc *desc; |
| 51 | int irq; |
| 52 | |
| 53 | for_each_irq_desc(irq, desc) { |
| 54 | unsigned long flags; |
| 55 | |
Thomas Gleixner | 239007b | 2009-11-17 16:46:45 +0100 | [diff] [blame] | 56 | raw_spin_lock_irqsave(&desc->lock, flags); |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 57 | __enable_irq(desc, irq, true); |
Thomas Gleixner | 239007b | 2009-11-17 16:46:45 +0100 | [diff] [blame] | 58 | raw_spin_unlock_irqrestore(&desc->lock, flags); |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 59 | } |
| 60 | } |
| 61 | EXPORT_SYMBOL_GPL(resume_device_irqs); |
| 62 | |
| 63 | /** |
| 64 | * check_wakeup_irqs - check if any wake-up interrupts are pending |
| 65 | */ |
| 66 | int check_wakeup_irqs(void) |
| 67 | { |
| 68 | struct irq_desc *desc; |
| 69 | int irq; |
| 70 | |
Thomas Gleixner | d209a69 | 2011-03-11 21:22:14 +0100 | [diff] [blame] | 71 | for_each_irq_desc(irq, desc) { |
| 72 | if (irqd_is_wakeup_set(&desc->irq_data)) { |
| 73 | if (desc->istate & IRQS_PENDING) |
| 74 | return -EBUSY; |
| 75 | continue; |
| 76 | } |
| 77 | /* |
| 78 | * Check the non wakeup interrupts whether they need |
| 79 | * to be masked before finally going into suspend |
| 80 | * state. That's for hardware which has no wakeup |
| 81 | * source configuration facility. The chip |
| 82 | * implementation indicates that with |
| 83 | * IRQCHIP_MASK_ON_SUSPEND. |
| 84 | */ |
| 85 | if (desc->istate & IRQS_SUSPENDED && |
| 86 | irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND) |
| 87 | mask_irq(desc); |
| 88 | } |
Rafael J. Wysocki | 0a0c516 | 2009-03-16 22:33:49 +0100 | [diff] [blame] | 89 | |
| 90 | return 0; |
| 91 | } |