Add mdev support

general/overlay/etc/init.d/S10mdev

@@ -0,0 +1,21 @@
+#!/bin/sh
+#
+# Start mdev....
+#
+
+case "$1" in
+  start)
+        echo "Starting mdev..."
+        # echo /sbin/mdev >/proc/sys/kernel/hotplug
+        /sbin/mdev -s
+        ;;
+  stop)
+        ;;
+  restart|reload)
+        ;;
+  *)
+        echo "Usage: $0 {start|stop|restart}"
+        exit 1
+esac
+
+exit $?

general/overlay/etc/mdev.conf

@@ -0,0 +1,22 @@
+# Provide user, group, and mode information for devices.  If a regex matches
+# the device name provided by sysfs, use the appropriate user:group and mode
+# instead of the default 0:0 660.
+#
+# Syntax:
+# [-]devicename_regex user:group mode [=path]|[>path]|[!] [@|$|*cmd args...]
+# [-]$ENVVAR=regex    user:group mode [=path]|[>path]|[!] [@|$|*cmd args...]
+# [-]@maj,min[-min2]  user:group mode [=path]|[>path]|[!] [@|$|*cmd args...]
+#
+# [-]: do not stop on this match, continue reading mdev.conf
+# =: move, >: move and create a symlink
+# !: do not create device node
+# @|$|*: run@cmd if $ACTION=add,  $cmd if $ACTION=remove, *cmd in all cases
+#
+#
+#
+mmcblk[0-9] root:disk 660
+mmcblk[0-9]p[0-9] root:disk 660 *(/lib/mdev/automount.sh)
+#
+sd[a-z] root:disk 660
+sd[a-z] [0-9] root:disk 660 *(/lib/mdev/automount.sh)
+#

general/overlay/lib/mdev/automount.sh

@@ -0,0 +1,33 @@
+#!/bin/sh
+
+destdir=/mnt
+
+my_umount()
+{
+    if grep -qs "^/dev/$1 " /proc/mounts ; then
+        umount "${destdir}/$1";
+    fi
+
+    [ -d "${destdir}/$1" ] && rmdir "${destdir}/$1"
+}
+
+my_mount()
+{
+    mkdir -p "${destdir}/$1" || exit 1
+
+    if ! mount -t auto -o sync "/dev/$1" "${destdir}/$1"; then
+        # failed to mount, clean up mountpoint
+        rmdir "${destdir}/$1"
+        exit 1
+    fi
+}
+
+case "${ACTION}" in
+add|"")
+    my_umount ${MDEV}
+    my_mount ${MDEV}
+    ;;
+remove)
+    my_umount ${MDEV}
+    ;;
+esac