procd: fix initial nand sysupgrade

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

Backport of r42884

git-svn-id: svn://svn.openwrt.org/openwrt/branches/barrier_breaker@42887 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/system/procd/files/nand.sh

@@ -10,6 +10,18 @@ CI_KERNPART="kernel"
 # 'ubi' partition on NAND contains UBI
 CI_UBIPART="ubi"
 
+ubi_mknod() {
+	local dir="$1"
+	local dev="/dev/$(basename $dir)"
+
+	[ -e "$dev" ] && return 0
+
+	local devid="$(cat $dir/dev)"
+	local major="${devid%%:*}"
+	local minor="${devid##*:}"
+	mknod "$dev" c $major $minor
+}
+
 nand_find_volume() {
 	local ubidevdir ubivoldir
 	ubidevdir="/sys/devices/virtual/ubi/$1"
@@ -18,6 +30,7 @@ nand_find_volume() {
 		[ ! -d "$ubivoldir" ] && continue
 		if [ "$( cat $ubivoldir/name )" = "$2" ]; then
 			basename $ubivoldir
+			ubi_mknod "$ubivoldir"
 			return 0
 		fi
 	done
@@ -33,6 +46,7 @@ nand_find_ubi() {
 		[ ! "$mtdnum" ] && continue
 		if [ "$mtdnum" = "$cmtdnum" ]; then
 			ubidev=$( basename $ubidevdir )
+			ubi_mknod "$ubidevdir"
 			echo $ubidev
 			return 0
 		fi