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diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile
--- a/share/man/man9/Makefile
+++ b/share/man/man9/Makefile
@@ -1040,6 +1040,7 @@
MLINKS+=device_add_child.9 device_add_child_ordered.9
MLINKS+=device_enable.9 device_disable.9 \
device_enable.9 device_is_enabled.9
+MLINKS+=device_get_children.9 device_has_children.9
MLINKS+=device_get_ivars.9 device_set_ivars.9
MLINKS+=device_get_name.9 device_get_nameunit.9
MLINKS+=device_get_state.9 device_busy.9 \
diff --git a/share/man/man9/device_get_children.9 b/share/man/man9/device_get_children.9
--- a/share/man/man9/device_get_children.9
+++ b/share/man/man9/device_get_children.9
@@ -1,6 +1,7 @@
.\" -*- nroff -*-
.\"
.\" Copyright (c) 1998 Doug Rabson
+.\" Copyright (c) 2025 Dag-Erling Smørgrav <des@FreeBSD.org>
.\"
.\" All rights reserved.
.\"
@@ -26,21 +27,27 @@
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd August 23, 2008
+.Dd November 26, 2025
.Dt DEVICE_GET_CHILDREN 9
.Os
.Sh NAME
-.Nm device_get_children
-.Nd get a list of devices connected to a device
+.Nm device_get_children ,
+.Nm device_has_children
+.Nd examine devices connected to a device
.Sh SYNOPSIS
.In sys/param.h
.In sys/bus.h
.Ft int
.Fn device_get_children "device_t dev" "device_t **devlistp" "int *devcountp"
+.Ft bool
+.Fn device_has_children "device_t dev"
.Sh DESCRIPTION
-Retrieve a list of all device instances currently connected to
-.Pa dev
-and return the list in
+The
+.Nm device_get_children
+function retrieves a list of all device instances currently connected
+to
+.Fa dev .
+It returns the list in
.Fa *devlistp
and the count in
.Fa *devcountp .
@@ -50,11 +57,35 @@
and
.Fa devcountp
are not changed when an error is returned.
+.Pp
+As a special case, if
+.Fa devlistp
+is null, no memory is allocated but the count is still returned in
+.Fa *devcountp .
+.Pp
+The
+.Nm device_has_children
+function returns
+.Dv true
+if
+.Fa dev
+has at least one child and
+.Dv false
+if does not have any.
.Sh RETURN VALUES
-Zero is returned on success, otherwise an appropriate error is returned.
+The
+.Nm device_get_children
+function returns zero on success and an appropriate error otherwise.
+The
+.Nm device_has_children
+function returns true if the specified device has at least one child
+and false otherwise.
.Sh SEE ALSO
.Xr devclass 9 ,
.Xr device 9
.Sh AUTHORS
+.An -nosplit
This manual page was written by
-.An Doug Rabson .
+.An Doug Rabson Aq Mt dfr@FreeBSD.org
+and
+.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org .
diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -1831,6 +1831,20 @@
return (dev->parent);
}
+/**
+ * @brief Check if a device has children
+ *
+ * @param dev the device to examine
+ *
+ * @rerval true the device has at least one child
+ * @retval false the device has no children
+ */
+bool
+device_has_children(device_t dev)
+{
+ return (!TAILQ_EMPTY(&dev->children));
+}
+
/**
* @brief Get a list of children of a device
*
@@ -1858,6 +1872,10 @@
TAILQ_FOREACH(child, &dev->children, link) {
count++;
}
+ if (devlistp == NULL) {
+ *devcountp = count;
+ return (0);
+ }
if (count == 0) {
*devlistp = NULL;
*devcountp = 0;
diff --git a/sys/sys/bus.h b/sys/sys/bus.h
--- a/sys/sys/bus.h
+++ b/sys/sys/bus.h
@@ -703,6 +703,7 @@
driver_t *device_get_driver(device_t dev);
u_int32_t device_get_flags(device_t dev);
device_t device_get_parent(device_t dev);
+bool device_has_children(device_t dev);
int device_get_children(device_t dev, device_t **listp, int *countp);
void *device_get_ivars(device_t dev);
void device_set_ivars(device_t dev, void *ivars);

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