PM: Introduce pm_power_off_prepare
Introduce the pm_power_off_prepare() callback that can be registered by the
interested platforms in analogy with pm_idle() and pm_power_off(), used for
preparing the system to power off (needed by ACPI).
This allows us to drop acpi_sysclass and device_acpi that are only defined in
order to register the ACPI power off preparation callback, which is needed by
pm_power_off() registered in a much different way.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/acpi/sleep/poweroff.c b/drivers/acpi/sleep/poweroff.c
index 240dde9..39e40d5 100644
--- a/drivers/acpi/sleep/poweroff.c
+++ b/drivers/acpi/sleep/poweroff.c
@@ -39,7 +39,13 @@
#ifdef CONFIG_PM
-void acpi_power_off(void)
+static void acpi_power_off_prepare(void)
+{
+ /* Prepare to power off the system */
+ acpi_sleep_prepare(ACPI_STATE_S5);
+}
+
+static void acpi_power_off(void)
{
/* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
printk("%s called\n", __FUNCTION__);
@@ -48,27 +54,6 @@
acpi_enter_sleep_state(ACPI_STATE_S5);
}
-static int acpi_shutdown(struct sys_device *x)
-{
- switch (system_state) {
- case SYSTEM_POWER_OFF:
- /* Prepare to power off the system */
- return acpi_sleep_prepare(ACPI_STATE_S5);
- default:
- return 0;
- }
-}
-
-static struct sysdev_class acpi_sysclass = {
- set_kset_name("acpi"),
- .shutdown = acpi_shutdown
-};
-
-static struct sys_device device_acpi = {
- .id = 0,
- .cls = &acpi_sysclass,
-};
-
static int acpi_poweroff_init(void)
{
if (!acpi_disabled) {
@@ -78,13 +63,8 @@
status =
acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
if (ACPI_SUCCESS(status)) {
- int error;
- error = sysdev_class_register(&acpi_sysclass);
- if (!error)
- error = sysdev_register(&device_acpi);
- if (!error)
- pm_power_off = acpi_power_off;
- return error;
+ pm_power_off_prepare = acpi_power_off_prepare;
+ pm_power_off = acpi_power_off;
}
}
return 0;
diff --git a/include/linux/pm.h b/include/linux/pm.h
index 2735b7c..ad3cc2e 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -101,6 +101,7 @@
*/
extern void (*pm_idle)(void);
extern void (*pm_power_off)(void);
+extern void (*pm_power_off_prepare)(void);
typedef int __bitwise suspend_state_t;
diff --git a/kernel/sys.c b/kernel/sys.c
index 18987c7..d40e40a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -100,6 +100,13 @@
EXPORT_SYMBOL(cad_pid);
/*
+ * If set, this is used for preparing the system to power off.
+ */
+
+void (*pm_power_off_prepare)(void);
+EXPORT_SYMBOL(pm_power_off_prepare);
+
+/*
* Notifier list for kernel code which wants to be called
* at shutdown. This is used to stop any idling DMA operations
* and the like.
@@ -867,6 +874,8 @@
void kernel_power_off(void)
{
kernel_shutdown_prepare(SYSTEM_POWER_OFF);
+ if (pm_power_off_prepare)
+ pm_power_off_prepare();
printk(KERN_EMERG "Power down.\n");
machine_power_off();
}