/**
* acpi_suspend_enter - Actually enter a sleep state.
* @pm_state: ignored
*
* Flush caches and go to sleep. For STR we have to call arch-specific
* assembly, which in turn call acpi_enter_sleep_state().
* It's unfortunate, but it works. Please fix if you're feeling frisky.
*/
static int acpi_suspend_enter(suspend_state_t pm_state)
{
acpi_status status = AE_OK;
unsigned long flags = 0;
u32 acpi_state = acpi_target_sleep_state;
ACPI_FLUSH_CPU_CACHE();
/* Do arch specific saving of state. */
if (acpi_state == ACPI_STATE_S3) {
int error = acpi_save_state_mem();
if (error)
return error;
}
local_irq_save(flags);
acpi_enable_wakeup_device(acpi_state);
switch (acpi_state) {
case ACPI_STATE_S1:
barrier();
status = acpi_enter_sleep_state(acpi_state);
break;
case ACPI_STATE_S3:
do_suspend_lowlevel();
break;
}
/* Reprogram control registers and execute _BFS */
acpi_leave_sleep_state_prep(acpi_state);
/* ACPI 3.0 specs (P62) says that it's the responsibility
* of the OSPM to clear the status bit [ implying that the
* POWER_BUTTON event should not reach userspace ]
*/
if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
/*
* Disable and clear GPE status before interrupt is enabled. Some GPEs
* (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
* acpi_leave_sleep_state will reenable specific GPEs later
*/
acpi_hw_disable_all_gpes();
local_irq_restore(flags);
printk(KERN_DEBUG "Back to C!\n");
/* restore processor state */
if (acpi_state == ACPI_STATE_S3)
acpi_restore_state_mem();
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
static int acpi_pm_enter(suspend_state_t pm_state)
{
acpi_status status = AE_OK;
unsigned long flags = 0;
u32 acpi_state = acpi_suspend_states[pm_state];
ACPI_FLUSH_CPU_CACHE();
/* Do arch specific saving of state. */
if (pm_state > PM_SUSPEND_STANDBY) {
int error = acpi_save_state_mem();
if (error)
return error;
}
local_irq_save(flags);
acpi_enable_wakeup_device(acpi_state);
switch (pm_state) {
case PM_SUSPEND_STANDBY:
barrier();
status = acpi_enter_sleep_state(acpi_state);
break;
case PM_SUSPEND_MEM:
do_suspend_lowlevel();
break;
case PM_SUSPEND_DISK:
if (acpi_pm_ops.pm_disk_mode == PM_DISK_PLATFORM)
status = acpi_enter_sleep_state(acpi_state);
else
do_suspend_lowlevel_s4bios();
break;
case PM_SUSPEND_MAX:
acpi_power_off();
break;
default:
return -EINVAL;
}
local_irq_restore(flags);
printk(KERN_DEBUG "Back to C!\n");
/* restore processor state
* We should only be here if we're coming back from STR or STD.
* And, in the case of the latter, the memory image should have already
* been loaded from disk.
*/
if (pm_state > PM_SUSPEND_STANDBY)
acpi_restore_state_mem();
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
/**
* acpi_system_save_state - save OS specific state and power down devices
* @state: sleep state we're entering.
*
* This handles saving all context to memory, and possibly disk.
* First, we call to the device driver layer to save device state.
* Once we have that, we save whatevery processor and kernel state we
* need to memory.
* If we're entering S4, we then write the memory image to disk.
*
* Only then it is safe for us to power down devices, since we may need
* the disks and upstream buses to write to.
*/
acpi_status
acpi_system_save_state(
u32 state)
{
int error = 0;
/* Send notification to devices that they will be suspended.
* If any device or driver cannot make the transition, either up
* or down, we'll get an error back.
*/
if (state > ACPI_STATE_S1) {
error = pm_send_all(PM_SAVE_STATE, (void *)3);
if (error)
return AE_ERROR;
}
if (state <= ACPI_STATE_S5) {
/* Tell devices to stop I/O and actually save their state.
* It is theoretically possible that something could fail,
* so handle that gracefully..
*/
if (state > ACPI_STATE_S1 && state != ACPI_STATE_S5) {
error = pm_send_all(PM_SUSPEND, (void *)3);
if (error) {
/* Tell devices to restore state if they have
* it saved and to start taking I/O requests.
*/
pm_send_all(PM_RESUME, (void *)0);
return error;
}
}
/* flush caches */
ACPI_FLUSH_CPU_CACHE();
/* Do arch specific saving of state. */
if (state > ACPI_STATE_S1) {
error = acpi_save_state_mem();
/* TBD: if no s4bios, write codes for
* acpi_save_state_disk()...
*/
#if 0
if (!error && (state == ACPI_STATE_S4))
error = acpi_save_state_disk();
#endif
if (error) {
pm_send_all(PM_RESUME, (void *)0);
return error;
}
}
}
/* disable interrupts
* Note that acpi_suspend -- our caller -- will do this once we return.
* But, we want it done early, so we don't get any suprises during
* the device suspend sequence.
*/
ACPI_DISABLE_IRQS();
/* Unconditionally turn off devices.
* Obvious if we enter a sleep state.
* If entering S5 (soft off), this should put devices in a
* quiescent state.
*/
if (state > ACPI_STATE_S1) {
error = pm_send_all(PM_SUSPEND, (void *)3);
/* We're pretty screwed if we got an error from this.
* We try to recover by simply calling our own restore_state
* function; see above for definition.
*
* If it's S5 though, go through with it anyway..
*/
if (error && state != ACPI_STATE_S5)
acpi_system_restore_state(state);
}
return error ? AE_ERROR : AE_OK;
}
static int acpi_pm_enter(suspend_state_t pm_state)
{
acpi_status status = AE_OK;
unsigned long flags = 0;
u32 acpi_state = acpi_suspend_states[pm_state];
ACPI_FLUSH_CPU_CACHE();
/* Do arch specific saving of state. */
if (pm_state > PM_SUSPEND_STANDBY) {
int error = acpi_save_state_mem();
if (error)
return error;
}
local_irq_save(flags);
acpi_enable_wakeup_device(acpi_state);
switch (pm_state) {
case PM_SUSPEND_STANDBY:
barrier();
status = acpi_enter_sleep_state(acpi_state);
break;
case PM_SUSPEND_MEM:
if (unlikely(acpi_simulate_suspend_to_ram)) {
printk(KERN_INFO "ACPI: simulating suspend-to-RAM: "
"not calling BIOS.\n");
} else {
do_suspend_lowlevel();
}
break;
case PM_SUSPEND_DISK:
if (acpi_pm_ops.pm_disk_mode == PM_DISK_PLATFORM)
status = acpi_enter_sleep_state(acpi_state);
break;
case PM_SUSPEND_MAX:
acpi_power_off();
break;
default:
return -EINVAL;
}
/* ACPI 3.0 specs (P62) says that it's the responsabilty
* of the OSPM to clear the status bit [ implying that the
* POWER_BUTTON event should not reach userspace ]
*/
if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
local_irq_restore(flags);
printk(KERN_DEBUG "Back to C!\n");
/* restore processor state
* We should only be here if we're coming back from STR or STD.
* And, in the case of the latter, the memory image should have already
* been loaded from disk.
*/
if (pm_state > PM_SUSPEND_STANDBY)
acpi_restore_state_mem();
return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}
