PM / Core: Introduce struct syscore_ops for core subsystems PM
Some subsystems need to carry out suspend/resume and shutdown
operations with one CPU on-line and interrupts disabled. The only
way to register such operations is to define a sysdev class and
a sysdev specifically for this purpose which is cumbersome and
inefficient. Moreover, the arguments taken by sysdev suspend,
resume and shutdown callbacks are practically never necessary.
For this reason, introduce a simpler interface allowing subsystems
to register operations to be executed very late during system suspend
and shutdown and very early during resume in the form of
strcut syscore_ops objects.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 1832bd2..aeabd26 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -23,6 +23,7 @@
#include <linux/cpu.h>
#include <linux/freezer.h>
#include <linux/gfp.h>
+#include <linux/syscore_ops.h>
#include <scsi/scsi_scan.h>
#include <asm/suspend.h>
@@ -272,6 +273,8 @@
local_irq_disable();
error = sysdev_suspend(PMSG_FREEZE);
+ if (!error)
+ error = syscore_suspend();
if (error) {
printk(KERN_ERR "PM: Some system devices failed to power down, "
"aborting hibernation\n");
@@ -295,6 +298,7 @@
}
Power_up:
+ syscore_resume();
sysdev_resume();
/* NOTE: dpm_resume_noirq() is just a resume() for devices
* that suspended with irqs off ... no overall powerup.
@@ -403,6 +407,8 @@
local_irq_disable();
error = sysdev_suspend(PMSG_QUIESCE);
+ if (!error)
+ error = syscore_suspend();
if (error)
goto Enable_irqs;
@@ -429,6 +435,7 @@
restore_processor_state();
touch_softlockup_watchdog();
+ syscore_resume();
sysdev_resume();
Enable_irqs:
@@ -516,6 +523,7 @@
local_irq_disable();
sysdev_suspend(PMSG_HIBERNATE);
+ syscore_suspend();
if (pm_wakeup_pending()) {
error = -EAGAIN;
goto Power_up;
@@ -526,6 +534,7 @@
while (1);
Power_up:
+ syscore_resume();
sysdev_resume();
local_irq_enable();
enable_nonboot_cpus();