drivers/acpi/sleep/poweroff.c

   1 /*
   2  * poweroff.c - ACPI handler for powering off the system.
   3  *
   4  * AKA S5, but it is independent of whether or not the kernel supports
   5  * any other sleep support in the system.
   6  *
   7  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   8  *
   9  * This file is released under the GPLv2.
  10  */
  11
  12 #include <linux/pm.h>
  13 #include <linux/init.h>
  14 #include <acpi/acpi_bus.h>
  15 #include <linux/sched.h>
  16 #include <linux/sysdev.h>
  17 #include <asm/io.h>
  18 #include "sleep.h"
  19
  20 int acpi_sleep_prepare(u32 acpi_state)
  21 {
  22 #ifdef CONFIG_ACPI_SLEEP
  23         /* do we have a wakeup address for S2 and S3? */
  24         if (acpi_state == ACPI_STATE_S3) {
  25                 if (!acpi_wakeup_address) {
  26                         return -EFAULT;
  27                 }
  28                 acpi_set_firmware_waking_vector((acpi_physical_address)
  29                                                 virt_to_phys((void *)
  30                                                              acpi_wakeup_address));
  31
  32         }
  33         ACPI_FLUSH_CPU_CACHE();
  34         acpi_enable_wakeup_device_prep(acpi_state);
  35 #endif
  36         if (acpi_state == ACPI_STATE_S5) {
  37                 acpi_wakeup_gpe_poweroff_prepare();
  38         }
  39         acpi_enter_sleep_state_prep(acpi_state);
  40         return 0;
  41 }
  42
  43 #ifdef CONFIG_PM
  44
  45 void acpi_power_off(void)
  46 {
  47         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
  48         printk("%s called\n", __FUNCTION__);
  49         local_irq_disable();
  50         /* Some SMP machines only can poweroff in boot CPU */
  51         acpi_enter_sleep_state(ACPI_STATE_S5);
  52 }
  53
  54 static int acpi_shutdown(struct sys_device *x)
  55 {
  56         if (system_state == SYSTEM_POWER_OFF) {
  57                 /* Prepare if we are going to power off the system */
  58                 return acpi_sleep_prepare(ACPI_STATE_S5);
  59         }
  60         return 0;
  61 }
  62
  63 static struct sysdev_class acpi_sysclass = {
  64         set_kset_name("acpi"),
  65         .shutdown = acpi_shutdown
  66 };
  67
  68 static struct sys_device device_acpi = {
  69         .id = 0,
  70         .cls = &acpi_sysclass,
  71 };
  72
  73 static int acpi_poweroff_init(void)
  74 {
  75         if (!acpi_disabled) {
  76                 u8 type_a, type_b;
  77                 acpi_status status;
  78
  79                 status =
  80                     acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
  81                 if (ACPI_SUCCESS(status)) {
  82                         int error;
  83                         error = sysdev_class_register(&acpi_sysclass);
  84                         if (!error)
  85                                 error = sysdev_register(&device_acpi);
  86                         if (!error)
  87                                 pm_power_off = acpi_power_off;
  88                         return error;
  89                 }
  90         }
  91         return 0;
  92 }
  93
  94 late_initcall(acpi_poweroff_init);
  95
  96 #endif                          /* CONFIG_PM */