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>

1 files changed, 16 insertions, 12 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;
 }