Index: subr_bus.c
===================================================================
RCS file: /home/ncvs/src/sys/kern/subr_bus.c,v
retrieving revision 1.207
diff -u -r1.207 subr_bus.c
--- subr_bus.c	20 Mar 2008 21:24:32 -0000	1.207
+++ subr_bus.c	11 Apr 2008 04:47:13 -0000
@@ -31,6 +31,7 @@
 
 #include <sys/param.h>
 #include <sys/conf.h>
+#include <sys/devio.h>
 #include <sys/filio.h>
 #include <sys/lock.h>
 #include <sys/kernel.h>
@@ -403,8 +404,10 @@
 static int
 devopen(struct cdev *dev, int oflags, int devtype, d_thread_t *td)
 {
+#if 0
 	if (devsoftc.inuse)
 		return (EBUSY);
+#endif
 	/* move to init */
 	devsoftc.inuse = 1;
 	devsoftc.nonblock = 0;
@@ -479,6 +482,26 @@
 			devsoftc.async_proc = NULL;
 		return (0);
 
+	case DEVIOC_SUSPEND:
+	case DEVIOC_RESUME:
+	{
+		devclass_t dc;
+		device_t dev;
+		struct device_ioctl *dio = (struct device_ioctl *)data;
+		int err;
+
+		dc = devclass_find(dio->dio_devclass);
+		if (dc == NULL)
+			return (ENXIO);
+		dev = devclass_get_device(dc, dio->dio_unit);
+		if (dev == NULL)
+			return (ENXIO);
+		if (cmd == DEVIOC_SUSPEND)
+			err = BUS_SUSPEND_CHILD(device_get_parent(dev), dev);
+		else
+			err = BUS_RESUME_CHILD(device_get_parent(dev), dev);
+		return (err);
+	}
 		/* (un)Support for other fcntl() calls. */
 	case FIOCLEX:
 	case FIONCLEX:
@@ -2352,7 +2375,7 @@
 int
 device_probe_and_attach(device_t dev)
 {
-	int error;
+	int error, disable;
 
 	GIANT_REQUIRED;
 
@@ -2374,6 +2397,11 @@
 		}
 		return (error);
 	}
+	disable = 0;
+	resource_int_value(device_get_name(dev), device_get_unit(dev),
+	    "disable", &disable);
+	if (disable)
+		return (0);
 	error = device_attach(dev);
 
 	return (error);
@@ -2871,6 +2899,18 @@
 	}
 }
 
+int
+bus_generic_resume_child(device_t dev, device_t child)
+{
+	return DEVICE_RESUME(child);
+}
+
+int
+bus_generic_suspend_child(device_t dev, device_t child)
+{
+	return DEVICE_SUSPEND(child);
+}
+
 device_t
 bus_generic_add_child(device_t dev, int order, const char *name, int unit)
 {