ARM: Use struct syscore_ops instead of sysdevs for PM in common code

Convert some ARM architecture's common code to using
struct syscore_ops objects for power management instead of sysdev
classes and sysdevs.

This simplifies the code and reduces the kernel's memory footprint.
It also is necessary for removing sysdevs from the kernel entirely in
the future.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 28 insertions, 35 deletions

diff --git a/arch/arm/kernel/leds.c b/arch/arm/kernel/leds.c
index 31a316c1777b..0f107dcb0347 100644
--- a/arch/arm/kernel/leds.c
+++ b/arch/arm/kernel/leds.c
@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/sysdev.h>
+#include <linux/syscore_ops.h>
 
 #include <asm/leds.h>
 
@@ -69,36 +70,37 @@ static ssize_t leds_store(struct sys_device *dev,
 
 static SYSDEV_ATTR(event, 0200, NULL, leds_store);
 
-static int leds_suspend(struct sys_device *dev, pm_message_t state)
+static struct sysdev_class leds_sysclass = {
+	.name		= "leds",
+};
+
+static struct sys_device leds_device = {
+	.id		= 0,
+	.cls		= &leds_sysclass,
+};
+
+static int leds_suspend(void)
 {
 	leds_event(led_stop);
 	return 0;
 }
 
-static int leds_resume(struct sys_device *dev)
+static void leds_resume(void)
 {
 	leds_event(led_start);
-	return 0;
 }
 
-static int leds_shutdown(struct sys_device *dev)
+static void leds_shutdown(void)
 {
 	leds_event(led_halted);
-	return 0;
 }
 
-static struct sysdev_class leds_sysclass = {
-	.name		= "leds",
+static struct syscore_ops leds_syscore_ops = {
 	.shutdown	= leds_shutdown,
 	.suspend	= leds_suspend,
 	.resume		= leds_resume,
 };
 
-static struct sys_device leds_device = {
-	.id		= 0,
-	.cls		= &leds_sysclass,
-};
-
 static int __init leds_init(void)
 {
 	int ret;
@@ -107,6 +109,8 @@ static int __init leds_init(void)
 		ret = sysdev_register(&leds_device);
 	if (ret == 0)
 		ret = sysdev_create_file(&leds_device, &attr_event);
+	if (ret == 0)
+		register_syscore_ops(&leds_syscore_ops);
 	return ret;
 }
 
diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c
index 1ff46cabc7ef..cb634c3e28e9 100644
--- a/arch/arm/kernel/time.c
+++ b/arch/arm/kernel/time.c
@@ -21,7 +21,7 @@
 #include <linux/timex.h>
 #include <linux/errno.h>
 #include <linux/profile.h>
-#include <linux/sysdev.h>
+#include <linux/syscore_ops.h>
 #include <linux/timer.h>
 #include <linux/irq.h>
 
@@ -115,48 +115,37 @@ void timer_tick(void)
 #endif
 
 #if defined(CONFIG_PM) && !defined(CONFIG_GENERIC_CLOCKEVENTS)
-static int timer_suspend(struct sys_device *dev, pm_message_t state)
+static int timer_suspend(void)
 {
-	struct sys_timer *timer = container_of(dev, struct sys_timer, dev);
-
-	if (timer->suspend != NULL)
-		timer->suspend();
+	if (system_timer->suspend)
+		system_timer->suspend();
 
 	return 0;
 }
 
-static int timer_resume(struct sys_device *dev)
+static void timer_resume(void)
 {
-	struct sys_timer *timer = container_of(dev, struct sys_timer, dev);
-
-	if (timer->resume != NULL)
-		timer->resume();
-
-	return 0;
+	if (system_timer->resume)
+		system_timer->resume();
 }
 #else
 #define timer_suspend NULL
 #define timer_resume NULL
 #endif
 
-static struct sysdev_class timer_sysclass = {
-	.name		= "timer",
+static struct syscore_ops timer_syscore_ops = {
 	.suspend	= timer_suspend,
 	.resume		= timer_resume,
 };
 
-static int __init timer_init_sysfs(void)
+static int __init timer_init_syscore_ops(void)
 {
-	int ret = sysdev_class_register(&timer_sysclass);
-	if (ret == 0) {
-		system_timer->dev.cls = &timer_sysclass;
-		ret = sysdev_register(&system_timer->dev);
-	}
+	register_syscore_ops(&timer_syscore_ops);
 
-	return ret;
+	return 0;
 }
 
-device_initcall(timer_init_sysfs);
+device_initcall(timer_init_syscore_ops);
 
 void __init time_init(void)
 {