libs/sys: fix luci.sys.wifi.channels()

diff --git a/libs/sys/luasrc/sys.lua b/libs/sys/luasrc/sys.lua
index 817217b..1cf8b9f 100644 (file)
--- a/libs/sys/luasrc/sys.lua
+++ b/libs/sys/luasrc/sys.lua
@@ -722,10 +722,14 @@ end
 -- @param iface        Wireless interface (optional)
 -- @return             Table of available channels
 function wifi.channels(iface)
 -- @param iface        Wireless interface (optional)
 -- @return             Table of available channels
 function wifi.channels(iface)

-       local t = iwinfo.type(iface or "")
+       local stat, iwinfo = pcall(require, "iwinfo")

        local cns
        local cns

-       if iface and t and iwinfo[t] then
-               cns = iwinfo[t].freqlist(iface)
+
+       if stat then
+               local t = iwinfo.type(iface or "")
+               if iface and t and iwinfo[t] then
+                       cns = iwinfo[t].freqlist(iface)
+               end

        end
 
        if not cns or #cns == 0 then
        end
 
        if not cns or #cns == 0 then