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         acpi_gpe_sleep_prepare(acpi_state);
  37         acpi_enter_sleep_state_prep(acpi_state);
  38         return 0;
  39 }
  40
  41 #ifdef CONFIG_PM
  42
  43 void acpi_power_off(void)
  44 {
  45         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
  46         printk("%s called\n", __FUNCTION__);
  47         local_irq_disable();
  48         /* Some SMP machines only can poweroff in boot CPU */
  49         acpi_enter_sleep_state(ACPI_STATE_S5);
  50 }
  51
  52 static int acpi_shutdown(struct sys_device *x)
  53 {
  54         switch (system_state) {
  55         case SYSTEM_POWER_OFF:
  56                 /* Prepare to power off the system */
  57                 return acpi_sleep_prepare(ACPI_STATE_S5);
  58         case SYSTEM_SUSPEND_DISK:
  59                 /* Prepare to suspend the system to disk */
  60                 return acpi_sleep_prepare(ACPI_STATE_S4);
  61         default:
  62                 return 0;
  63         }
  64 }
  65
  66 static struct sysdev_class acpi_sysclass = {
  67         set_kset_name("acpi"),
  68         .shutdown = acpi_shutdown
  69 };
  70
  71 static struct sys_device device_acpi = {
  72         .id = 0,
  73         .cls = &acpi_sysclass,
  74 };
  75
  76 static int acpi_poweroff_init(void)
  77 {
  78         if (!acpi_disabled) {
  79                 u8 type_a, type_b;
  80                 acpi_status status;
  81
  82                 status =
  83                     acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
  84                 if (ACPI_SUCCESS(status)) {
  85                         int error;
  86                         error = sysdev_class_register(&acpi_sysclass);
  87                         if (!error)
  88                                 error = sysdev_register(&device_acpi);
  89                         if (!error)
  90                                 pm_power_off = acpi_power_off;
  91                         return error;
  92                 }
  93         }
  94         return 0;
  95 }
  96
  97 late_initcall(acpi_poweroff_init);
  98
  99 #endif                          /* CONFIG_PM */