PM: add kconfig option for deprecated .../power/state files
Add a new PM_SYSFS_DEPRECATED config option to control whether or
not the /sys/devices/.../power/state files are provided. This will
make it easier to get rid of that mechanism when the time comes,
and to verify that userspace tools work right without it.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index e55b3c2..2d47517 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -7,6 +7,8 @@
#include "power.h"
+#ifdef CONFIG_PM_SYSFS_DEPRECATED
+
/**
* state - Control current power state of device
*
@@ -66,6 +68,8 @@
static DEVICE_ATTR(state, 0644, state_show, state_store);
+#endif /* CONFIG_PM_SYSFS_DEPRECATED */
+
/*
* wakeup - Report/change current wakeup option for device
*
@@ -139,7 +143,9 @@
static struct attribute * power_attrs[] = {
+#ifdef CONFIG_PM_SYSFS_DEPRECATED
&dev_attr_state.attr,
+#endif
&dev_attr_wakeup.attr,
NULL,
};
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 619ecab..1ed9720 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -53,6 +53,17 @@
CAUTION: this option will cause your machine's real-time clock to be
set to an invalid time after a resume.
+config PM_SYSFS_DEPRECATED
+ bool "Driver model /sys/devices/.../power/state files (DEPRECATED)"
+ depends on PM && SYSFS
+ default n
+ help
+ The driver model started out with a sysfs file intended to provide
+ a userspace hook for device power management. This feature has never
+ worked very well, except for limited testing purposes, and so it will
+ be removed. It's not clear that a generic mechanism could really
+ handle the wide variability of device power states; any replacements
+ are likely to be bus or driver specific.
config SOFTWARE_SUSPEND
bool "Software Suspend"