- Convert a lot of homebrew debugging output to use the ACPI CA debugging

   infrastructure.  It's not perfect, but it's a lot better than what
   we've been using so far.  The following rules apply to this:
    o BSD component names should be capitalised
    o Layer names should be taken from the non-CA set for now.  We
      may elect to add some new BSD-specific layers later.

 - Make it possible to turn off selective debugging flags or layers
   by listing them in debug.acpi.layer or debug.acpi.level prefixed
   with !.

 - Fully implement support for avoiding nodes in the ACPI namespace.
   Nodes may be listed in the debug.acpi.avoid environment variable;
   these nodes and all their children will be ignored (although still
   scanned over) by ACPI functions which scan the namespace.  Multiple
   nodes can be specified, separated by whitespace.

 - Implement support for selectively disabling ACPI subsystem components
   via the debug.acpi.disable environment variable.  The following
   components can be disabled:
    o bus	creation/scanning of the ACPI 'bus'
    o children	attachment of children to the ACPI 'bus'
    o button	the acpi_button control-method button driver
    o ec	the acpi_ec embedded-controller driver
    o isa	acpi replacement of PnP BIOS for ISA device discovery
    o lid	the control-method lid switch driver
    o pci	pci root-bus discovery
    o processor CPU power/speed management
    o thermal	system temperature detection and control
    o timer	ACPI timecounter
   Multiple components may be disabled by specifying their name(s)
   separated by whitespace.

 - Add support for ioctl registration.  ACPI subsystem components may
   register ioctl handlers with the /dev/acpi generic ioctl handler,
   allowing us to avoid the need for a multitude of /dev/acpi* control
   devices, etc.

1 files changed, 20 insertions, 5 deletions

diff --git a/sys/dev/acpica/acpi_timer.c b/sys/dev/acpica/acpi_timer.c
index e586aae..19ebcc0 100644
--- a/sys/dev/acpica/acpi_timer.c
+++ b/sys/dev/acpica/acpi_timer.c
@@ -36,6 +36,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	SYSTEM_CONTROL
+MODULE_NAME("TIMER")
+
 #define ACPITIMER_MAGIC 0x524d4954	/* "TIMR" */
 
 struct acpi_timer_softc {
@@ -73,28 +79,35 @@ acpi_timer_identify(driver_t *driver, device_t parent)
     device_t			dev;
     char			desc[40];
 
+    FUNCTION_TRACE(__FUNCTION__);
+
+    if (acpi_disabled("timer"))
+	return_VOID;
+
     buf.Pointer = &fadt;
     buf.Length = sizeof(fadt);
     if ((status = AcpiGetTable(ACPI_TABLE_FADT, 1, &buf)) != AE_OK) {
 	device_printf(parent, "can't locate FADT - %s\n", acpi_strerror(status));
-	return;
+	return_VOID;
     }
     if (buf.Length != sizeof(fadt)) {
 	device_printf(parent, "invalid FADT\n");
-	return;
+	return_VOID;
     }
 
     if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_timer", 0)) == NULL) {
 	device_printf(parent, "could not add acpi_timer0\n");
-	return;
+	return_VOID;
     }
     if (acpi_set_magic(dev, ACPITIMER_MAGIC)) {
 	device_printf(dev, "could not set magic\n");
-	return;
+	return_VOID;
     }
 
     sprintf(desc, "%d-bit timer at 3.579545MHz", fadt.TmrValExt ? 32 : 24);
     device_set_desc_copy(dev, desc);
+
+    return_VOID;
 }
 
 static int
@@ -110,8 +123,10 @@ acpi_timer_attach(device_t dev)
 {
     struct acpi_timer_softc		*sc;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = device_get_softc(dev);
     sc->tm_dev = dev;
 
-    return(0);
+    return_VALUE(0);
 }