PM: Make CONFIG_PM depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME)

From the users' point of view CONFIG_PM is really only used for
making it possible to set CONFIG_SUSPEND, CONFIG_HIBERNATION,
CONFIG_PM_RUNTIME and (surprisingly enough) CONFIG_XEN_SAVE_RESTORE
(CONFIG_PM_OPP also depends on CONFIG_PM, but quite artificially).
However, both CONFIG_SUSPEND and CONFIG_HIBERNATION require platform
support (independent of CONFIG_PM) and it is not quite obvious that
CONFIG_PM has to be set for CONFIG_XEN_SAVE_RESTORE to be available.
Thus, from the users' point of view, it would be more logical to
automatically select CONFIG_PM if any of the above options depending
on it are set.

Make CONFIG_PM depend on (CONFIG_PM_SLEEP || CONFIG_PM_RUNTIME),
which will cause it to be selected when any of CONFIG_SUSPEND,
CONFIG_HIBERNATION, CONFIG_PM_RUNTIME, CONFIG_XEN_SAVE_RESTORE is
set and will clarify its meaning.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

2 files changed, 7 insertions, 24 deletions

diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index 5b54892e4bc3..2c876ed723d0 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -38,7 +38,7 @@ config XEN_MAX_DOMAIN_MEMORY
 
 config XEN_SAVE_RESTORE
        bool
-       depends on XEN && PM
+       depends on XEN
        default y
 
 config XEN_DEBUG_FS
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 265729966ece..d739cf612e50 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -1,23 +1,7 @@
 config PM
-        bool "Power Management support"
-        depends on !IA64_HP_SIM
-        ---help---
-          "Power Management" means that parts of your computer are shut
-          off or put into a power conserving "sleep" mode if they are not
-          being used.  There are two competing standards for doing this: APM
-          and ACPI.  If you want to use either one, say Y here and then also
-          to the requisite support below.
-
-          Power Management is most important for battery powered laptop
-          computers; if you have a laptop, check out the Linux Laptop home
-          page on the WWW at <http://www.linux-on-laptops.com/> or
-          Tuxmobil - Linux on Mobile Computers at <http://www.tuxmobil.org/>
-          and the Battery Powered Linux mini-HOWTO, available from
-          <http://www.tldp.org/docs.html#howto>.
-
-          Note that, even if you say N here, Linux on the x86 architecture
-          will issue the hlt instruction if nothing is to be done, thereby
-          sending the processor to sleep and saving power.
+        bool
+        depends on PM_SLEEP || PM_RUNTIME
+        default y
 
 config PM_DEBUG
         bool "Power Management Debug Support"
@@ -102,7 +86,7 @@ config PM_SLEEP_ADVANCED_DEBUG
 
 config SUSPEND
         bool "Suspend to RAM and standby"
-        depends on PM && ARCH_SUSPEND_POSSIBLE
+        depends on ARCH_SUSPEND_POSSIBLE
         default y
         ---help---
           Allow the system to enter sleep states in which main memory is
@@ -133,7 +117,7 @@ config SUSPEND_FREEZER
 
 config HIBERNATION
         bool "Hibernation (aka 'suspend to disk')"
-        depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE
+        depends on SWAP && ARCH_HIBERNATION_POSSIBLE
         select LZO_COMPRESS
         select LZO_DECOMPRESS
         ---help---
@@ -224,7 +208,7 @@ config APM_EMULATION
 
 config PM_RUNTIME
         bool "Run-time PM core functionality"
-        depends on PM
+        depends on !IA64_HP_SIM
         ---help---
           Enable functionality allowing I/O devices to be put into energy-saving
           (low power) states at run time (or autosuspended) after a specified
@@ -246,7 +230,6 @@ config ARCH_HAS_OPP
 
 config PM_OPP
         bool "Operating Performance Point (OPP) Layer library"
-        depends on PM
         depends on ARCH_HAS_OPP
         ---help---
           SOCs have a standard set of tuples consisting of frequency and