PM / PowerPC: Use struct syscore_ops instead of sysdevs for PM

Make some PowerPC architecture's code use 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, 35 insertions, 49 deletions

diff --git a/arch/powerpc/sysdev/ipic.c b/arch/powerpc/sysdev/ipic.c
index fa438be962b..596554a8725 100644
--- a/arch/powerpc/sysdev/ipic.c
+++ b/arch/powerpc/sysdev/ipic.c
@@ -18,7 +18,7 @@
 #include <linux/stddef.h>
 #include <linux/sched.h>
 #include <linux/signal.h>
-#include <linux/sysdev.h>
+#include <linux/syscore_ops.h>
 #include <linux/device.h>
 #include <linux/bootmem.h>
 #include <linux/spinlock.h>
@@ -902,7 +902,7 @@ static struct {
 	u32 sercr;
 } ipic_saved_state;
 
-static int ipic_suspend(struct sys_device *sdev, pm_message_t state)
+static int ipic_suspend(void)
 {
 	struct ipic *ipic = primary_ipic;
 
@@ -933,7 +933,7 @@ static int ipic_suspend(struct sys_device *sdev, pm_message_t state)
 	return 0;
 }
 
-static int ipic_resume(struct sys_device *sdev)
+static void ipic_resume(void)
 {
 	struct ipic *ipic = primary_ipic;
 
@@ -949,44 +949,26 @@ static int ipic_resume(struct sys_device *sdev)
 	ipic_write(ipic->regs, IPIC_SECNR, ipic_saved_state.secnr);
 	ipic_write(ipic->regs, IPIC_SERMR, ipic_saved_state.sermr);
 	ipic_write(ipic->regs, IPIC_SERCR, ipic_saved_state.sercr);
-
-	return 0;
 }
 #else
 #define ipic_suspend NULL
 #define ipic_resume NULL
 #endif
 
-static struct sysdev_class ipic_sysclass = {
-	.name = "ipic",
+static struct syscore_ops ipic_syscore_ops = {
 	.suspend = ipic_suspend,
 	.resume = ipic_resume,
 };
 
-static struct sys_device device_ipic = {
-	.id		= 0,
-	.cls		= &ipic_sysclass,
-};
-
-static int __init init_ipic_sysfs(void)
+static int __init init_ipic_syscore(void)
 {
-	int rc;
-
 	if (!primary_ipic || !primary_ipic->regs)
 		return -ENODEV;
-	printk(KERN_DEBUG "Registering ipic with sysfs...\n");
 
-	rc = sysdev_class_register(&ipic_sysclass);
-	if (rc) {
-		printk(KERN_ERR "Failed registering ipic sys class\n");
-		return -ENODEV;
-	}
-	rc = sysdev_register(&device_ipic);
-	if (rc) {
-		printk(KERN_ERR "Failed registering ipic sys device\n");
-		return -ENODEV;
-	}
+	printk(KERN_DEBUG "Registering ipic system core operations\n");
+	register_syscore_ops(&ipic_syscore_ops);
+
 	return 0;
 }
 
-subsys_initcall(init_ipic_sysfs);
+subsys_initcall(init_ipic_syscore);
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index f91c065bed5..7e5dc8f4984 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -27,6 +27,7 @@
 #include <linux/spinlock.h>
 #include <linux/pci.h>
 #include <linux/slab.h>
+#include <linux/syscore_ops.h>
 
 #include <asm/ptrace.h>
 #include <asm/signal.h>
@@ -1702,9 +1703,8 @@ void mpic_reset_core(int cpu)
 #endif /* CONFIG_SMP */
 
 #ifdef CONFIG_PM
-static int mpic_suspend(struct sys_device *dev, pm_message_t state)
+static void mpic_suspend_one(struct mpic *mpic)
 {
-	struct mpic *mpic = container_of(dev, struct mpic, sysdev);
 	int i;
 
 	for (i = 0; i < mpic->num_sources; i++) {
@@ -1713,13 +1713,22 @@ static int mpic_suspend(struct sys_device *dev, pm_message_t state)
 		mpic->save_data[i].dest =
 			mpic_irq_read(i, MPIC_INFO(IRQ_DESTINATION));
 	}
+}
+
+static int mpic_suspend(void)
+{
+	struct mpic *mpic = mpics;
+
+	while (mpic) {
+		mpic_suspend_one(mpic);
+		mpic = mpic->next;
+	}
 
 	return 0;
 }
 
-static int mpic_resume(struct sys_device *dev)
+static void mpic_resume_one(struct mpic *mpic)
 {
-	struct mpic *mpic = container_of(dev, struct mpic, sysdev);
 	int i;
 
 	for (i = 0; i < mpic->num_sources; i++) {
@@ -1746,33 +1755,28 @@ static int mpic_resume(struct sys_device *dev)
 	}
 #endif
 	} /* end for loop */
+}
 
-	return 0;
+static void mpic_resume(void)
+{
+	struct mpic *mpic = mpics;
+
+	while (mpic) {
+		mpic_resume_one(mpic);
+		mpic = mpic->next;
+	}
 }
-#endif
 
-static struct sysdev_class mpic_sysclass = {
-#ifdef CONFIG_PM
+static struct syscore_ops mpic_syscore_ops = {
 	.resume = mpic_resume,
 	.suspend = mpic_suspend,
-#endif
-	.name = "mpic",
 };
 
 static int mpic_init_sys(void)
 {
-	struct mpic *mpic = mpics;
-	int error, id = 0;
-
-	error = sysdev_class_register(&mpic_sysclass);
-
-	while (mpic && !error) {
-		mpic->sysdev.cls = &mpic_sysclass;
-		mpic->sysdev.id = id++;
-		error = sysdev_register(&mpic->sysdev);
-		mpic = mpic->next;
-	}
-	return error;
+	register_syscore_ops(&mpic_syscore_ops);
+	return 0;
 }
 
 device_initcall(mpic_init_sys);
+#endif