Update the suspend/resume user API while maintaining backwards compat.

Improvements:
* /etc/rc.suspend,rc.resume are always run, no matter the source of the
  suspend request (user or kernel, apm or acpi)
* suspend now requires positive user acknowledgement.  If a user program
  wants to cancel the suspend, they can.  If one of the user programs
  hangs or doesn't respond within 10 seconds, the system suspends anyway.
* /dev/apm is clonable, allowing multiple listeners for suspend events.
  In the future, xorg-server can use this to be informed about suspend
  even if there are other listeners (i.e. apmd).

Changes:
* Two new ACPI ioctls:  REQSLPSTATE and ACKSLPSTATE.  Request begins the
  process of suspending by notifying all listeners.  acpi is monitored by
  devd(8) and /dev/apm listener(s) are also counted.  Users register their
  approval or disapproval via Ack.  If anyone disapproves, suspend is vetoed.
* Old user programs or kernel modules that used SETSLPSTATE continue to
  work.  A message is printed once that this interface is deprecated.
* acpiconf gains the -k flag to ack the suspend request.  This flag is
  undocumented on purpose since it's only used by /etc/rc.suspend.  It is
  not intended to be a permanent change and will be removed once a better
  power API is implemented.
* S5 (power off) is no longer supported via acpiconf -s 5 or apm -z/-Z.
  This restores previous behavior of halt/shutdown -p being the interface.
* Miscellaneous improvements to error reporting

Approved by:	re

3 files changed, 32 insertions, 9 deletions

diff --git a/etc/devd.conf b/etc/devd.conf
index 59ac15f..94fbb79 100644
--- a/etc/devd.conf
+++ b/etc/devd.conf
@@ -239,6 +239,19 @@ notify 10 {
 	action "logger -p kern.warn 'ZFS: checksum mismatch, zpool=$pool path=$vdev_path offset=$zio_offset size=$zio_size'";
 };
 
+# User requested suspend, so perform preparation steps and then execute
+# the actual suspend process.
+notify 10 {
+	match "system"		"ACPI";
+	match "subsystem"	"Suspend";
+	action "/etc/rc.suspend acpi $notify";
+};
+notify 10 {
+	match "system"		"ACPI";
+	match "subsystem"	"Resume";
+	action "/etc/rc.resume acpi $notify";
+};
+
 /* EXAMPLES TO END OF FILE
 
 # The following might be an example of something that a vendor might
@@ -277,6 +290,7 @@ detach 10 {
 # Button:	Button pressed (0 for power, 1 for sleep)
 # CMBAT:	ACPI battery events
 # Lid:		Lid state (0 is closed, 1 is open)
+# Suspend, Resume: Suspend and resume notification
 # Thermal:	ACPI thermal zone events
 #
 # This example calls a script when the AC state changes, passing the
diff --git a/etc/rc.resume b/etc/rc.resume
index 4e133e0..54f49c5 100755
--- a/etc/rc.resume
+++ b/etc/rc.resume
@@ -30,7 +30,7 @@
 # sample run command file for APM Resume Event
 
 if [ $# -ne 2 ]; then
-	echo "Usage: $0 [apm|acpi] [standby,suspend|1-5]"
+	echo "Usage: $0 [apm|acpi] [standby,suspend|1-4]"
 	exit 1
 fi
 
@@ -48,9 +48,13 @@ fi
 # pccardq | awk -F '~' '$5 == "inactive" \
 #	{ printf("pccardc power %d 1", $1); }' | sh
 
-# UHCI has trouble resuming so we just load/unload it.  You
-# should add any other kernel modules you want reloaded here.
-# kldload usb
+# If a device driver has problems resuming, try unloading it before
+# suspend and reloading it on resume.  Example:
+# kldunload usb
+
+# wpa_supplicant(8) doesn't seem to reassociate during resume.  Uncomment
+# the following to signal it to reassociate.
+# /usr/sbin/wpa_cli reassociate
 
 logger -t $subsystem resumed at `date +'%Y%m%d %H:%M:%S'`
 sync && sync && sync
diff --git a/etc/rc.suspend b/etc/rc.suspend
index 26fe198..4028b32 100755
--- a/etc/rc.suspend
+++ b/etc/rc.suspend
@@ -30,7 +30,7 @@
 # sample run command file for APM Suspend Event
 
 if [ $# -ne 2 ]; then
-	echo "Usage: $0 [apm|acpi] [standby,suspend|1-5]"
+	echo "Usage: $0 [apm|acpi] [standby,suspend|1-4]"
 	exit 1
 fi
 
@@ -48,15 +48,20 @@ echo $$ 2> /dev/null > /var/run/rc.suspend.pid
 # pccardq | awk -F '~' '$5 == "filled" && $4 ~ /sio/ \
 #	{ printf("pccardc power %d 0", $1); }' | sh
 
-# UHCI has trouble resuming so we just load/unload it.  You
-# should add any other kernel modules you want unloaded here.
+# If a device driver has problems suspending, try unloading it before
+# suspend and reloading it on resume.  Example:
 # kldunload usb
 
 logger -t $subsystem suspend at `date +'%Y%m%d %H:%M:%S'`
 sync && sync && sync
-[ $subsystem = "apm" ] && sleep 3
+sleep 3
 
 rm -f /var/run/rc.suspend.pid
-[ $subsystem = "apm" ] && zzz
+if [ $subsystem = "apm" ]; then
+	/usr/sbin/zzz
+else
+	# Notify the kernel to continue the suspend process
+	/usr/sbin/acpiconf -k 0
+fi
 
 exit 0