1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. 4 * 5 * This file contains power management functions related to interrupts. 6 */ 7 8 #include <linux/irq.h> 9 #include <linux/module.h> 10 #include <linux/interrupt.h> 11 #include <linux/suspend.h> 12 #include <linux/syscore_ops.h> 13 14 #include "internals.h" 15 16 bool irq_pm_check_wakeup(struct irq_desc *desc) 17 { 18 if (irqd_is_wakeup_armed(&desc->irq_data)) { 19 irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); 20 desc->istate |= IRQS_SUSPENDED | IRQS_PENDING; 21 desc->depth++; 22 irq_disable(desc); 23 pm_system_irq_wakeup(irq_desc_get_irq(desc)); 24 return true; 25 } 26 return false; 27 } 28 29 /* 30 * Called from __setup_irq() with desc->lock held after @action has 31 * been installed in the action chain. 32 */ 33 void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) 34 { 35 desc->nr_actions++; 36 37 if (action->flags & IRQF_FORCE_RESUME) 38 desc->force_resume_depth++; 39 40 WARN_ON_ONCE(desc->force_resume_depth && 41 desc->force_resume_depth != desc->nr_actions); 42 43 if (action->flags & IRQF_NO_SUSPEND) 44 desc->no_suspend_depth++; 45 else if (action->flags & IRQF_COND_SUSPEND) 46 desc->cond_suspend_depth++; 47 48 WARN_ON_ONCE(desc->no_suspend_depth && 49 (desc->no_suspend_depth + 50 desc->cond_suspend_depth) != desc->nr_actions); 51 } 52 53 /* 54 * Called from __free_irq() with desc->lock held after @action has 55 * been removed from the action chain. 56 */ 57 void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) 58 { 59 desc->nr_actions--; 60 61 if (action->flags & IRQF_FORCE_RESUME) 62 desc->force_resume_depth--; 63 64 if (action->flags & IRQF_NO_SUSPEND) 65 desc->no_suspend_depth--; 66 else if (action->flags & IRQF_COND_SUSPEND) 67 desc->cond_suspend_depth--; 68 } 69 70 static bool suspend_device_irq(struct irq_desc *desc) 71 { 72 if (!desc->action || irq_desc_is_chained(desc) || 73 desc->no_suspend_depth) 74 return false; 75 76 if (irqd_is_wakeup_set(&desc->irq_data)) { 77 irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED); 78 /* 79 * We return true here to force the caller to issue 80 * synchronize_irq(). We need to make sure that the 81 * IRQD_WAKEUP_ARMED is visible before we return from 82 * suspend_device_irqs(). 83 */ 84 return true; 85 } 86 87 desc->istate |= IRQS_SUSPENDED; 88 __disable_irq(desc); 89 90 /* 91 * Hardware which has no wakeup source configuration facility 92 * requires that the non wakeup interrupts are masked at the 93 * chip level. The chip implementation indicates that with 94 * IRQCHIP_MASK_ON_SUSPEND. 95 */ 96 if (irq_desc_get_chip(desc)->flags & IRQCHIP_MASK_ON_SUSPEND) 97 mask_irq(desc); 98 return true; 99 } 100 101 /** 102 * suspend_device_irqs - disable all currently enabled interrupt lines 103 * 104 * During system-wide suspend or hibernation device drivers need to be 105 * prevented from receiving interrupts and this function is provided 106 * for this purpose. 107 * 108 * So we disable all interrupts and mark them IRQS_SUSPENDED except 109 * for those which are unused, those which are marked as not 110 * suspendable via an interrupt request with the flag IRQF_NO_SUSPEND 111 * set and those which are marked as active wakeup sources. 112 * 113 * The active wakeup sources are handled by the flow handler entry 114 * code which checks for the IRQD_WAKEUP_ARMED flag, suspends the 115 * interrupt and notifies the pm core about the wakeup. 116 */ 117 void suspend_device_irqs(void) 118 { 119 struct irq_desc *desc; 120 int irq; 121 122 for_each_irq_desc(irq, desc) { 123 unsigned long flags; 124 bool sync; 125 126 if (irq_settings_is_nested_thread(desc)) 127 continue; 128 raw_spin_lock_irqsave(&desc->lock, flags); 129 sync = suspend_device_irq(desc); 130 raw_spin_unlock_irqrestore(&desc->lock, flags); 131 132 if (sync) 133 synchronize_irq(irq); 134 } 135 } 136 EXPORT_SYMBOL_GPL(suspend_device_irqs); 137 138 static void resume_irq(struct irq_desc *desc) 139 { 140 irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); 141 142 if (desc->istate & IRQS_SUSPENDED) 143 goto resume; 144 145 /* Force resume the interrupt? */ 146 if (!desc->force_resume_depth) 147 return; 148 149 /* Pretend that it got disabled ! */ 150 desc->depth++; 151 irq_state_set_disabled(desc); 152 irq_state_set_masked(desc); 153 resume: 154 desc->istate &= ~IRQS_SUSPENDED; 155 __enable_irq(desc); 156 } 157 158 static void resume_irqs(bool want_early) 159 { 160 struct irq_desc *desc; 161 int irq; 162 163 for_each_irq_desc(irq, desc) { 164 unsigned long flags; 165 bool is_early = desc->action && 166 desc->action->flags & IRQF_EARLY_RESUME; 167 168 if (!is_early && want_early) 169 continue; 170 if (irq_settings_is_nested_thread(desc)) 171 continue; 172 173 raw_spin_lock_irqsave(&desc->lock, flags); 174 resume_irq(desc); 175 raw_spin_unlock_irqrestore(&desc->lock, flags); 176 } 177 } 178 179 /** 180 * rearm_wake_irq - rearm a wakeup interrupt line after signaling wakeup 181 * @irq: Interrupt to rearm 182 */ 183 void rearm_wake_irq(unsigned int irq) 184 { 185 unsigned long flags; 186 struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL); 187 188 if (!desc || !(desc->istate & IRQS_SUSPENDED) || 189 !irqd_is_wakeup_set(&desc->irq_data)) 190 return; 191 192 desc->istate &= ~IRQS_SUSPENDED; 193 irqd_set(&desc->irq_data, IRQD_WAKEUP_ARMED); 194 __enable_irq(desc); 195 196 irq_put_desc_busunlock(desc, flags); 197 } 198 199 /** 200 * irq_pm_syscore_ops - enable interrupt lines early 201 * 202 * Enable all interrupt lines with %IRQF_EARLY_RESUME set. 203 */ 204 static void irq_pm_syscore_resume(void) 205 { 206 resume_irqs(true); 207 } 208 209 static struct syscore_ops irq_pm_syscore_ops = { 210 .resume = irq_pm_syscore_resume, 211 }; 212 213 static int __init irq_pm_init_ops(void) 214 { 215 register_syscore_ops(&irq_pm_syscore_ops); 216 return 0; 217 } 218 219 device_initcall(irq_pm_init_ops); 220 221 /** 222 * resume_device_irqs - enable interrupt lines disabled by suspend_device_irqs() 223 * 224 * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously 225 * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag 226 * set as well as those with %IRQF_FORCE_RESUME. 227 */ 228 void resume_device_irqs(void) 229 { 230 resume_irqs(false); 231 } 232 EXPORT_SYMBOL_GPL(resume_device_irqs); 233