[PATCH 27/44] x86: apm: Register with kernel poweroff handler

Guenter Roeck
2014-10-07T05:28:29Z

Register with kernel poweroff handler instead of setting pm_power_off
directly. Register with high priority value of 192 to reflect that
the original code overwrites existing poweroff handlers.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
arch/x86/kernel/apm_32.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index 5848744..84566a6 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -219,6 +219,7 @@
#include <linux/init.h>
#include <linux/time.h>
#include <linux/sched.h>
+#include <linux/notifier.h>
#include <linux/pm.h>
#include <linux/capability.h>
#include <linux/device.h>
@@ -981,7 +982,8 @@ recalc:
* on their first cpu.
*/

-static void apm_power_off(void)
+static int apm_power_off(struct notifier_block *this, unsigned long unused1,
+ void *unused2)
{
/* Some bioses don't like being called from CPU != 0 */
if (apm_info.realmode_power_off) {
@@ -990,8 +992,14 @@ static void apm_power_off(void)
} else {
(void)set_system_power_state(APM_STATE_OFF);
}
+ return NOTIFY_DONE;
}

+static struct notifier_block apm_poweroff_nb = {
+ .notifier_call = apm_power_off,
+ .priority = 192,
+};
+
#ifdef CONFIG_APM_DO_ENABLE

/**
@@ -1847,8 +1855,11 @@ static int apm(void *unused)
}

/* Install our power off handler.. */
- if (power_off)
- pm_power_off = apm_power_off;
+ if (power_off) {
+ error = register_poweroff_handler(&apm_poweroff_nb);
+ if (error)
+ pr_err("apm: Failed to register poweroff handler\n");
+ }

if (num_online_cpus() == 1 || smp) {
#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
@@ -2408,9 +2419,8 @@ static void __exit apm_exit(void)
apm_error("disengage power management", error);
}
misc_deregister(&apm_device);
+ unregister_poweroff_handler(&apm_poweroff_nb);
remove_proc_entry("apm", NULL);
- if (power_off)
- pm_power_off = NULL;
if (kapmd_task) {
kthread_stop(kapmd_task);
kapmd_task = NULL;
--
1.9.1