Add devctl(4) notify support to ACPI. Various subsystems now notify

userland whenever events occur.  See the example in devd.conf below
to see how to use it.

etc/devd.conf

@@ -93,4 +93,30 @@ detach 10 {
 	action "/etc/pccard_ether $device-name stop";
 };
 
+# Examples of notify hooks.  A notify is a generic way for a kernel
+# subsystem to send event notification to userland.
+#
+# Here are some examples of ACPI notify handlers.  ACPI subsystems that
+# generate notifies include the AC adapter, power/sleep buttons,
+# control method batteries, lid switch, and thermal zones.
+#
+# Information returned is not always the same as the ACPI notify
+# events.  See the ACPI specification for more information about
+# notifies.  Here is the information returned for each subsystem:
+#
+# ACAD:		AC line state (0 is offline, 1 is online)
+# Button:	Button pressed (0 for power, 1 for sleep)
+# CMBAT:	ACPI battery events
+# Lid:		Lid state (0 is closed, 1 is open)
+# Thermal:	ACPI thermal zone events
+#
+# This example calls a script when the AC state changes, passing the
+# notify value as the first argument.  If the state is 0x00, it might
+# call some sysctls to implement economy mode.  If 0x01, it might set
+# the mode to performance.
+notify 10 {
+	match "system"		"ACPI";
+	match "subsystem"	"ACAD";
+	action			"/etc/acpi_ac $notify";
+};
 */

sys/dev/acpica/acpi.c

@@ -51,6 +51,7 @@
 #include "acpi.h"
 #include <dev/acpica/acpivar.h>
 #include <dev/acpica/acpiio.h>
+#include <contrib/dev/acpica/acnamesp.h>
 
 MALLOC_DEFINE(M_ACPIDEV, "acpidev", "ACPI devices");
 
@@ -2054,6 +2055,27 @@ acpi_sleep_state_sysctl(SYSCTL_HANDLER_ARGS)
     return (error);
 }
 
+/* Inform devctl(4) when we receive a Notify. */
+void
+acpi_UserNotify(const char *subsystem, ACPI_HANDLE h, uint8_t notify)
+{
+    char		notify_buf[16];
+    ACPI_BUFFER		handle_buf;
+    ACPI_STATUS		status;
+
+    if (subsystem == NULL)
+	return;
+
+    handle_buf.Pointer = NULL;
+    handle_buf.Length = ACPI_ALLOCATE_BUFFER;
+    status = AcpiNsHandleToPathname(h, &handle_buf);
+    if (ACPI_FAILURE(status))
+	return;
+    snprintf(notify_buf, sizeof(notify_buf), "notify=0x%02x", notify);
+    devctl_notify("ACPI", subsystem, handle_buf.Pointer, notify_buf);
+    AcpiOsFree(handle_buf.Pointer);
+}
+
 #ifdef ACPI_DEBUG
 /*
  * Support for parsing debug options from the kernel environment.

sys/dev/acpica/acpi_acad.c

@@ -39,7 +39,7 @@
 #include <sys/conf.h>
 #include <sys/power.h>
 
-#include  "acpi.h"
+#include "acpi.h"
 #include <dev/acpica/acpivar.h>
 #include <dev/acpica/acpiio.h>
  
@@ -108,6 +108,8 @@ acpi_acad_get_status(void *context)
 				POWER_PROFILE_ECONOMY);
 	ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
 		    "%s Line\n", sc->status ? "On" : "Off");
+
+	acpi_UserNotify("ACAD", h, sc->status);
     }
 }
 

sys/dev/acpica/acpi_button.c

@@ -175,6 +175,8 @@ acpi_button_notify_pressed_for_sleep(void *arg)
     if (acpi_sc == NULL)
 	return_VOID;
 
+    acpi_UserNotify("Button", sc->button_handle, sc->button_type);
+
     switch (sc->button_type) {
     case ACPI_POWER_BUTTON:
 	ACPI_VPRINT(sc->button_dev, acpi_sc, "power button pressed\n");
@@ -202,6 +204,8 @@ acpi_button_notify_pressed_for_wakeup(void *arg)
     if (acpi_sc == NULL)
 	return_VOID;
 
+    acpi_UserNotify("Button", sc->button_handle, sc->button_type);
+
     switch (sc->button_type) {
     case ACPI_POWER_BUTTON:
 	ACPI_VPRINT(sc->button_dev, acpi_sc, "wakeup by power button\n");

sys/dev/acpica/acpi_cmbat.c

@@ -295,6 +295,8 @@ acpi_cmbat_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
     if ((sc = device_get_softc(dev)) == NULL)
 	return;
 
+    acpi_UserNotify("CMBAT", h, notify);
+
     switch (notify) {
     case ACPI_NOTIFY_DEVICE_CHECK:
     case ACPI_BATTERY_BST_CHANGE:

sys/dev/acpica/acpi_lid.c

@@ -54,7 +54,8 @@ static int	acpi_lid_attach(device_t dev);
 static int	acpi_lid_suspend(device_t dev);
 static int	acpi_lid_resume(device_t dev);
 static void	acpi_lid_notify_status_changed(void *arg);
-static void 	acpi_lid_notify_handler(ACPI_HANDLE h,UINT32 notify, void *context);
+static void 	acpi_lid_notify_handler(ACPI_HANDLE h, UINT32 notify,
+					void *context);
 
 static device_method_t acpi_lid_methods[] = {
     /* Device interface */
@@ -149,6 +150,8 @@ acpi_lid_notify_status_changed(void *arg)
     ACPI_VPRINT(sc->lid_dev, acpi_sc, "Lid %s\n",
 		sc->lid_status ? "opened" : "closed");
 
+    acpi_UserNotify("Lid", sc->lid_handle, sc->lid_status);
+
     if (sc->lid_status == 0)
 	EVENTHANDLER_INVOKE(acpi_sleep_event, acpi_sc->acpi_lid_switch_sx);
     else
@@ -178,4 +181,3 @@ acpi_lid_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 
     return_VOID;
 }
-

sys/dev/acpica/acpi_thermal.c

@@ -727,6 +727,8 @@ acpi_tz_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 	break;
     }
 
+    acpi_UserNotify("Thermal", h, notify);
+
     return_VOID;
 }
 

sys/dev/acpica/acpivar.h

@@ -188,6 +188,8 @@ extern ACPI_STATUS	acpi_SetIntrModel(int model);
 extern ACPI_STATUS	acpi_SetSleepState(struct acpi_softc *sc, int state);
 extern ACPI_STATUS	acpi_Enable(struct acpi_softc *sc);
 extern ACPI_STATUS	acpi_Disable(struct acpi_softc *sc);
+extern void		acpi_UserNotify(const char *subsystem, ACPI_HANDLE h,
+					uint8_t notify);
 
 struct acpi_parse_resource_set {
     void	(*set_init)(device_t dev, void **context);