PM: Rework struct platform_suspend_ops

There is no reason why the .prepare() and .finish() methods in 'struct
platform_suspend_ops' should take any arguments, since architectures don't use
these methods' argument in any practically meaningful way (ie.  either the
target system sleep state is conveyed to the platform by .set_target(), or
there is only one suspend state supported and it is indicated to the PM core
by .valid(), or .prepare() and .finish() aren't defined at all).   There also
is no reason why .finish() should return any result.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-omap1/pm.c

@@ -599,27 +599,15 @@ static void (*saved_idle)(void) = NULL;
 
 /*
  *	omap_pm_prepare - Do preliminary suspend work.
- *	@state:		suspend state we're entering.
  *
  */
-static int omap_pm_prepare(suspend_state_t state)
+static int omap_pm_prepare(void)
 {
-	int error = 0;
-
 	/* We cannot sleep in idle until we have resumed */
 	saved_idle = pm_idle;
 	pm_idle = NULL;
 
-	switch (state)
-	{
-	case PM_SUSPEND_STANDBY:
-	case PM_SUSPEND_MEM:
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	return error;
+	return 0;
 }
 
 
@@ -647,16 +635,14 @@ static int omap_pm_enter(suspend_state_t state)
 
 /**
  *	omap_pm_finish - Finish up suspend sequence.
- *	@state:		State we're coming out of.
  *
  *	This is called after we wake back up (or if entering the sleep state
  *	failed).
  */
 
-static int omap_pm_finish(suspend_state_t state)
+static void omap_pm_finish(void)
 {
 	pm_idle = saved_idle;
-	return 0;
 }
 
 

arch/arm/mach-omap2/pm.c

@@ -70,25 +70,12 @@ void omap2_pm_idle(void)
 	local_irq_enable();
 }
 
-static int omap2_pm_prepare(suspend_state_t state)
+static int omap2_pm_prepare(void)
 {
-	int error = 0;
-
 	/* We cannot sleep in idle until we have resumed */
 	saved_idle = pm_idle;
 	pm_idle = NULL;
-
-	switch (state)
-	{
-	case PM_SUSPEND_STANDBY:
-	case PM_SUSPEND_MEM:
-		break;
-
-	default:
-		return -EINVAL;
-	}
-
-	return error;
+	return 0;
 }
 
 #define INT0_WAKE_MASK	(OMAP_IRQ_BIT(INT_24XX_GPIO_BANK1) |	\
@@ -356,10 +343,9 @@ static int omap2_pm_enter(suspend_state_t state)
 	return ret;
 }
 
-static int omap2_pm_finish(suspend_state_t state)
+static void omap2_pm_finish(void)
 {
 	pm_idle = saved_idle;
-	return 0;
 }
 
 static struct platform_suspend_ops omap_pm_ops = {

arch/blackfin/mach-common/pm.c

@@ -89,28 +89,15 @@ void bfin_pm_suspend_standby_enter(void)
 #endif				/* CONFIG_PM_WAKEUP_GPIO_BY_SIC_IWR */
 }
 
-
 /*
- *	bfin_pm_prepare - Do preliminary suspend work.
- *	@state:		suspend state we're entering.
+ *	bfin_pm_valid - Tell the PM core that we only support the standby sleep
+ *			state
+ *	@state:		suspend state we're checking.
  *
  */
-static int bfin_pm_prepare(suspend_state_t state)
+static int bfin_pm_valid(suspend_state_t state)
 {
-	int error = 0;
-
-	switch (state) {
-	case PM_SUSPEND_STANDBY:
-		break;
-
-	case PM_SUSPEND_MEM:
-		return -ENOTSUPP;
-
-	default:
-		return -EINVAL;
-	}
-
-	return error;
+	return (state == PM_SUSPEND_STANDBY);
 }
 
 /*
@@ -135,38 +122,8 @@ static int bfin_pm_enter(suspend_state_t state)
 	return 0;
 }
 
-/*
- *	bfin_pm_finish - Finish up suspend sequence.
- *	@state:		State we're coming out of.
- *
- *	This is called after we wake back up (or if entering the sleep state
- *	failed).
- */
-static int bfin_pm_finish(suspend_state_t state)
-{
-	switch (state) {
-	case PM_SUSPEND_STANDBY:
-		break;
-
-	case PM_SUSPEND_MEM:
-		return -ENOTSUPP;
-
-	default:
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static int bfin_pm_valid(suspend_state_t state)
-{
-	return (state == PM_SUSPEND_STANDBY);
-}
-
 struct platform_suspend_ops bfin_pm_ops = {
-	.prepare = bfin_pm_prepare,
 	.enter = bfin_pm_enter,
-	.finish = bfin_pm_finish,
 	.valid	= bfin_pm_valid,
 };
 

arch/powerpc/platforms/52xx/lite5200_pm.c

@@ -1,5 +1,5 @@
 #include <linux/init.h>
-#include <linux/pm.h>
+#include <linux/suspend.h>
 #include <asm/io.h>
 #include <asm/time.h>
 #include <asm/mpc52xx.h>
@@ -18,6 +18,8 @@ static void __iomem *sram;
 static const int sram_size = 0x4000;	/* 16 kBytes */
 static void __iomem *mbar;
 
+static suspend_state_t lite5200_pm_target_state;
+
 static int lite5200_pm_valid(suspend_state_t state)
 {
 	switch (state) {
@@ -29,13 +31,22 @@ static int lite5200_pm_valid(suspend_state_t state)
 	}
 }
 
-static int lite5200_pm_prepare(suspend_state_t state)
+static int lite5200_pm_set_target(suspend_state_t state)
+{
+	if (lite5200_pm_valid(state)) {
+		lite5200_pm_target_state = state;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static int lite5200_pm_prepare(void)
 {
 	/* deep sleep? let mpc52xx code handle that */
-	if (state == PM_SUSPEND_STANDBY)
-		return mpc52xx_pm_prepare(state);
+	if (lite5200_pm_target_state == PM_SUSPEND_STANDBY)
+		return mpc52xx_pm_prepare();
 
-	if (state != PM_SUSPEND_MEM)
+	if (lite5200_pm_target_state != PM_SUSPEND_MEM)
 		return -EINVAL;
 
 	/* map registers */
@@ -190,24 +201,23 @@ static int lite5200_pm_enter(suspend_state_t state)
 	return 0;
 }
 
-static int lite5200_pm_finish(suspend_state_t state)
+static void lite5200_pm_finish(void)
 {
 	/* deep sleep? let mpc52xx code handle that */
-	if (state == PM_SUSPEND_STANDBY) {
-		return mpc52xx_pm_finish(state);
-	}
-	return 0;
+	if (lite5200_pm_target_state == PM_SUSPEND_STANDBY)
+		mpc52xx_pm_finish();
 }
 
-static struct pm_ops lite5200_pm_ops = {
+static struct platform_suspend_ops lite5200_pm_ops = {
 	.valid		= lite5200_pm_valid,
+	.set_target	= lite5200_pm_set_target,
 	.prepare	= lite5200_pm_prepare,
 	.enter		= lite5200_pm_enter,
 	.finish		= lite5200_pm_finish,
 };
 
 int __init lite5200_pm_init(void)
 {
-	pm_set_ops(&lite5200_pm_ops);
+	suspend_set_ops(&lite5200_pm_ops);
 	return 0;
 }

arch/powerpc/platforms/52xx/mpc52xx_pm.c

@@ -57,11 +57,8 @@ int mpc52xx_set_wakeup_gpio(u8 pin, u8 level)
 	return 0;
 }
 
-int mpc52xx_pm_prepare(suspend_state_t state)
+int mpc52xx_pm_prepare(void)
 {
-	if (state != PM_SUSPEND_STANDBY)
-		return -EINVAL;
-
 	/* map the whole register space */
 	mbar = mpc52xx_find_and_map("mpc5200");
 	if (!mbar) {
@@ -166,15 +163,13 @@ int mpc52xx_pm_enter(suspend_state_t state)
 	return 0;
 }
 
-int mpc52xx_pm_finish(suspend_state_t state)
+void mpc52xx_pm_finish(void)
 {
 	/* call board resume code */
 	if (mpc52xx_suspend.board_resume_finish)
 		mpc52xx_suspend.board_resume_finish(mbar);
 
 	iounmap(mbar);
-
-	return 0;
 }
 
 static struct platform_suspend_ops mpc52xx_pm_ops = {

drivers/acpi/sleep/main.c

@@ -85,13 +85,12 @@ static int acpi_pm_set_target(suspend_state_t pm_state)
 
 /**
  *	acpi_pm_prepare - Do preliminary suspend work.
- *	@pm_state: ignored
  *
  *	If necessary, set the firmware waking vector and do arch-specific
  *	nastiness to get the wakeup code to the waking vector.
  */
 
-static int acpi_pm_prepare(suspend_state_t pm_state)
+static int acpi_pm_prepare(void)
 {
 	int error = acpi_sleep_prepare(acpi_target_sleep_state);
 
@@ -160,13 +159,12 @@ static int acpi_pm_enter(suspend_state_t pm_state)
 
 /**
  *	acpi_pm_finish - Finish up suspend sequence.
- *	@pm_state: ignored
  *
  *	This is called after we wake back up (or if entering the sleep state
  *	failed). 
  */
 
-static int acpi_pm_finish(suspend_state_t pm_state)
+static void acpi_pm_finish(void)
 {
 	u32 acpi_state = acpi_target_sleep_state;
 
@@ -184,7 +182,6 @@ static int acpi_pm_finish(suspend_state_t pm_state)
 		init_8259A(0);
 	}
 #endif
-	return 0;
 }
 
 static int acpi_pm_state_valid(suspend_state_t pm_state)

include/asm-powerpc/mpc52xx.h

@@ -18,6 +18,8 @@
 #include <asm/prom.h>
 #endif /* __ASSEMBLY__ */
 
+#include <linux/suspend.h>
+
 
 /* ======================================================================== */
 /* Structures mapping of some unit register set                             */
@@ -267,9 +269,9 @@ extern int mpc52xx_set_wakeup_gpio(u8 pin, u8 level);
 extern int __init lite5200_pm_init(void);
 
 /* lite5200 calls mpc5200 suspend functions, so here they are */
-extern int mpc52xx_pm_prepare(suspend_state_t);
+extern int mpc52xx_pm_prepare(void);
 extern int mpc52xx_pm_enter(suspend_state_t);
-extern int mpc52xx_pm_finish(suspend_state_t);
+extern void mpc52xx_pm_finish(void);
 extern char saved_sram[0x4000]; /* reuse buffer from mpc52xx suspend */
 #endif
 #endif /* CONFIG_PM */

include/linux/suspend.h

@@ -46,12 +46,10 @@ typedef int __bitwise suspend_state_t;
  *	@prepare() fails.  If @set_target() fails (ie. returns nonzero),
  *	@prepare(), @enter() and @finish() will not be called by the PM core.
  *	This callback is optional.  However, if it is implemented, the argument
- *	passed to @prepare(), @enter() and @finish() is meaningless and should
- *	be ignored.
+ *	passed to @enter() is meaningless and should be ignored.
  *
  * @prepare: Prepare the platform for entering the system sleep state indicated
- *	by @set_target() or represented by the argument if @set_target() is not
- *	implemented.
+ *	by @set_target().
  *	@prepare() is called right after devices have been suspended (ie. the
  *	appropriate .suspend() method has been executed for each device) and
  *	before the nonboot CPUs are disabled (it is executed with IRQs enabled).
@@ -67,18 +65,17 @@ typedef int __bitwise suspend_state_t;
  *
  * @finish: Called when the system has just left a sleep state, right after
  *	the nonboot CPUs have been enabled and before devices are resumed (it is
- *	executed with IRQs enabled).  If @set_target() is not implemented, the
- *	argument represents the sleep state being left.
+ *	executed with IRQs enabled).
  *	This callback is optional, but should be implemented by the platforms
  *	that implement @prepare().  If implemented, it is always called after
  *	@enter() (even if @enter() fails).
  */
 struct platform_suspend_ops {
 	int (*valid)(suspend_state_t state);
 	int (*set_target)(suspend_state_t state);
-	int (*prepare)(suspend_state_t state);
+	int (*prepare)(void);
 	int (*enter)(suspend_state_t state);
-	int (*finish)(suspend_state_t state);
+	void (*finish)(void);
 };
 
 #ifdef CONFIG_SUSPEND

kernel/power/main.c

@@ -58,13 +58,6 @@ int suspend_valid_only_mem(suspend_state_t state)
 	return state == PM_SUSPEND_MEM;
 }
 
-
-static inline void pm_finish(suspend_state_t state)
-{
-	if (suspend_ops->finish)
-		suspend_ops->finish(state);
-}
-
 /**
  *	suspend_prepare - Do prep work before entering low-power state.
  *
@@ -171,7 +164,7 @@ int suspend_devices_and_enter(suspend_state_t state)
 		goto Resume_console;
 	}
 	if (suspend_ops->prepare) {
-		error = suspend_ops->prepare(state);
+		error = suspend_ops->prepare();
 		if (error)
 			goto Resume_devices;
 	}
@@ -180,7 +173,8 @@ int suspend_devices_and_enter(suspend_state_t state)
 		suspend_enter(state);
 
 	enable_nonboot_cpus();
-	pm_finish(state);
+	if (suspend_ops->finish)
+		suspend_ops->finish();
  Resume_devices:
 	device_resume();
  Resume_console: