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/sysdev.h>
  16 #include <asm/io.h>
  17 #include "sleep.h"
  18
  19 int acpi_sleep_prepare(u32 acpi_state)
  20 {
  21 #ifdef CONFIG_ACPI_SLEEP
  22         /* do we have a wakeup address for S2 and S3? */
  23         if (acpi_state == ACPI_STATE_S3) {
  24                 if (!acpi_wakeup_address) {
  25                         return -EFAULT;
  26                 }
  27                 acpi_set_firmware_waking_vector((acpi_physical_address)
  28                                                 virt_to_phys((void *)
  29                                                              acpi_wakeup_address));
  30
  31         }
  32         ACPI_FLUSH_CPU_CACHE();
  33         acpi_enable_wakeup_device_prep(acpi_state);
  34 #endif
  35         acpi_gpe_sleep_prepare(acpi_state);
  36         acpi_enter_sleep_state_prep(acpi_state);
  37         return 0;
  38 }
  39
  40 #ifdef CONFIG_PM
  41
  42 static void acpi_power_off_prepare(void)
  43 {
  44         /* Prepare to power off the system */
  45         acpi_sleep_prepare(ACPI_STATE_S5);
  46 }
  47
  48 static void acpi_power_off(void)
  49 {
  50         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
  51         printk("%s called\n", __FUNCTION__);
  52         local_irq_disable();
  53         /* Some SMP machines only can poweroff in boot CPU */
  54         acpi_enter_sleep_state(ACPI_STATE_S5);
  55 }
  56
  57 static int acpi_poweroff_init(void)
  58 {
  59         if (!acpi_disabled) {
  60                 u8 type_a, type_b;
  61                 acpi_status status;
  62
  63                 status =
  64                     acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
  65                 if (ACPI_SUCCESS(status)) {
  66                         pm_power_off_prepare = acpi_power_off_prepare;
  67                         pm_power_off = acpi_power_off;
  68                 }
  69         }
  70         return 0;
  71 }
  72
  73 late_initcall(acpi_poweroff_init);
  74
  75 #endif                          /* CONFIG_PM */