power management: implement pm_ops.valid for everybody

Almost all users of pm_ops only support mem sleep, don't check in .valid and
don't reject any others in .prepare so users can be confused if they check
/sys/power/state, especially when new states are added (these would then
result in s-t-r although they're supposed to be something different).

This patch implements a generic pm_valid_only_mem function that is then
exported for users and puts it to use in almost all existing pm_ops.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: linux-pm@lists.linux-foundation.org
Cc: Len Brown <lenb@kernel.org>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

11 files changed, 39 insertions, 55 deletions

diff --git a/arch/arm/common/sharpsl_pm.c b/arch/arm/common/sharpsl_pm.c
index 4cb895d4ae5b..5972df2b9af4 100644
--- a/arch/arm/common/sharpsl_pm.c
+++ b/arch/arm/common/sharpsl_pm.c
@@ -769,6 +769,7 @@ static struct pm_ops sharpsl_pm_ops = {
         .prepare        = pxa_pm_prepare,
         .enter          = corgi_pxa_pm_enter,
         .finish         = pxa_pm_finish,
+        .valid          = pm_valid_only_mem,
 };
 
 static int __init sharpsl_pm_probe(struct platform_device *pdev)
diff --git a/arch/arm/mach-omap1/pm.c b/arch/arm/mach-omap1/pm.c
index 4248117e5e3f..0383ab334270 100644
--- a/arch/arm/mach-omap1/pm.c
+++ b/arch/arm/mach-omap1/pm.c
@@ -701,6 +701,7 @@ static struct pm_ops omap_pm_ops ={
         .prepare        = omap_pm_prepare,
         .enter          = omap_pm_enter,
         .finish         = omap_pm_finish,
+        .valid          = pm_valid_only_mem,
 };
 
 static int __init omap_pm_init(void)
diff --git a/arch/arm/mach-omap2/pm.c b/arch/arm/mach-omap2/pm.c
index 3e9a128feea1..6f4a5436d0ce 100644
--- a/arch/arm/mach-omap2/pm.c
+++ b/arch/arm/mach-omap2/pm.c
@@ -373,6 +373,7 @@ static struct pm_ops omap_pm_ops = {
         .prepare        = omap2_pm_prepare,
         .enter          = omap2_pm_enter,
         .finish         = omap2_pm_finish,
+        .valid          = pm_valid_only_mem,
 };
 
 int __init omap2_pm_init(void)
diff --git a/arch/arm/mach-pnx4008/pm.c b/arch/arm/mach-pnx4008/pm.c
index 3649cd3dfc9a..2a137f33f752 100644
--- a/arch/arm/mach-pnx4008/pm.c
+++ b/arch/arm/mach-pnx4008/pm.c
@@ -107,50 +107,19 @@ static int pnx4008_pm_enter(suspend_state_t state)
         case PM_SUSPEND_MEM:
                 pnx4008_suspend();
                 break;
-        case PM_SUSPEND_DISK:
-                return -ENOTSUPP;
-        default:
-                return -EINVAL;
         }
         return 0;
 }
 
-/*
- * Called after processes are frozen, but before we shut down devices.
- */
-static int pnx4008_pm_prepare(suspend_state_t state)
-{
-        switch (state) {
-        case PM_SUSPEND_STANDBY:
-        case PM_SUSPEND_MEM:
-                break;
-
-        case PM_SUSPEND_DISK:
-                return -ENOTSUPP;
-                break;
-
-        default:
-                return -EINVAL;
-                break;
-        }
-        return 0;
-}
-
-/*
- * Called after devices are re-setup, but before processes are thawed.
- */
-static int pnx4008_pm_finish(suspend_state_t state)
+static int pnx4008_pm_valid(suspend_state_t state)
 {
-        return 0;
+        return (state == PM_SUSPEND_STANDBY) ||
+               (state == PM_SUSPEND_MEM);
 }
 
-/*
- * Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
- */
 static struct pm_ops pnx4008_pm_ops = {
-        .prepare = pnx4008_pm_prepare,
         .enter = pnx4008_pm_enter,
-        .finish = pnx4008_pm_finish,
+        .valid = pnx4008_pm_valid,
 };
 
 static int __init pnx4008_pm_init(void)
diff --git a/arch/arm/mach-pxa/pm.c b/arch/arm/mach-pxa/pm.c
index 0a99ef43b36f..6bf15ae73848 100644
--- a/arch/arm/mach-pxa/pm.c
+++ b/arch/arm/mach-pxa/pm.c
@@ -227,6 +227,7 @@ static struct pm_ops pxa_pm_ops = {
         .prepare        = pxa_pm_prepare,
         .enter          = pxa_pm_enter,
         .finish         = pxa_pm_finish,
+        .valid          = pm_valid_only_mem,
 };
 
 static int __init pxa_pm_init(void)
diff --git a/arch/arm/mach-sa1100/pm.c b/arch/arm/mach-sa1100/pm.c
index b0837113b2aa..d674cf343156 100644
--- a/arch/arm/mach-sa1100/pm.c
+++ b/arch/arm/mach-sa1100/pm.c
@@ -133,6 +133,7 @@ unsigned long sleep_phys_sp(void *sp)
 
 static struct pm_ops sa11x0_pm_ops = {
         .enter          = sa11x0_pm_enter,
+        .valid          = pm_valid_only_mem,
 };
 
 static int __init sa11x0_pm_init(void)
diff --git a/arch/arm/plat-s3c24xx/pm.c b/arch/arm/plat-s3c24xx/pm.c
index d6af3082af30..c6b03f8ab260 100644
--- a/arch/arm/plat-s3c24xx/pm.c
+++ b/arch/arm/plat-s3c24xx/pm.c
@@ -612,26 +612,9 @@ static int s3c2410_pm_enter(suspend_state_t state)
         return 0;
 }
 
-/*
- * Called after processes are frozen, but before we shut down devices.
- */
-static int s3c2410_pm_prepare(suspend_state_t state)
-{
-        return 0;
-}
-
-/*
- * Called after devices are re-setup, but before processes are thawed.
- */
-static int s3c2410_pm_finish(suspend_state_t state)
-{
-        return 0;
-}
-
 static struct pm_ops s3c2410_pm_ops = {
-        .prepare        = s3c2410_pm_prepare,
         .enter          = s3c2410_pm_enter,
-        .finish         = s3c2410_pm_finish,
+        .valid          = pm_valid_only_mem,
 };
 
 /* s3c2410_pm_init
diff --git a/arch/sh/boards/hp6xx/pm.c b/arch/sh/boards/hp6xx/pm.c
index 4b2f29a4bde9..8143d1b948e7 100644
--- a/arch/sh/boards/hp6xx/pm.c
+++ b/arch/sh/boards/hp6xx/pm.c
@@ -69,6 +69,7 @@ static int hp6x0_pm_enter(suspend_state_t state)
 
 static struct pm_ops hp6x0_pm_ops = {
         .enter          = hp6x0_pm_enter,
+        .valid          = pm_valid_only_mem,
 };
 
 static int __init hp6x0_pm_init(void)
diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c
index 37a0930fc0a6..f8c63410bcbf 100644
--- a/drivers/acpi/sleep/main.c
+++ b/drivers/acpi/sleep/main.c
@@ -168,9 +168,18 @@ int acpi_suspend(u32 acpi_state)
 
 static int acpi_pm_state_valid(suspend_state_t pm_state)
 {
-        u32 acpi_state = acpi_suspend_states[pm_state];
+        u32 acpi_state;
+
+        switch (pm_state) {
+        case PM_SUSPEND_ON:
+        case PM_SUSPEND_STANDBY:
+        case PM_SUSPEND_MEM:
+                acpi_state = acpi_suspend_states[pm_state];
 
-        return sleep_states[acpi_state];
+                return sleep_states[acpi_state];
+        default:
+                return 0;
+        }
 }
 
 static struct pm_ops acpi_pm_ops = {
diff --git a/include/linux/pm.h b/include/linux/pm.h
index c2a55f94c29a..6035209cf31e 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -128,6 +128,9 @@ typedef int __bitwise suspend_disk_method_t;
  *      always valid and never passed to this call.
  *      If not assigned, all suspend states are advertised as valid
  *      in /sys/power/state (but can still be rejected by prepare or enter.)
+ *      Since new states can be added for other platforms, you should
+ *      assign this callback. There is a %pm_valid_only_mem function
+ *      available if you only implemented mem sleep.
  *
  * @prepare: Prepare the platform for the given suspend state. Can return a
  *      negative error code if necessary.
@@ -165,6 +168,7 @@ extern void pm_set_ops(struct pm_ops *pm_ops);
 extern struct pm_ops *pm_ops;
 extern int pm_suspend(suspend_state_t state);
 
+extern int pm_valid_only_mem(suspend_state_t state);
 
 /**
  * arch_suspend_disable_irqs - disable IRQs for suspend
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 053c0a7d7f57..f94f4e20115a 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -48,6 +48,19 @@ void pm_set_ops(struct pm_ops * ops)
         mutex_unlock(&pm_mutex);
 }
 
+/**
+ * pm_valid_only_mem - generic memory-only valid callback
+ *
+ * pm_ops drivers that implement mem suspend only and only need
+ * to check for that in their .valid callback can use this instead
+ * of rolling their own .valid callback.
+ */
+int pm_valid_only_mem(suspend_state_t state)
+{
+        return state == PM_SUSPEND_MEM;
+}
+
+
 static inline void pm_finish(suspend_state_t state)
 {
         if (pm_ops->finish)