IEEE 802.11ac capable device from 2013. Supported in Chaos Calmer (trunk) builds.
Upgrade from earlier OpenWrt: http://downloads.openwrt.org/snapshots/trunk/ar71xx/generic/openwrt-ar71xx-generic-dgl-5500-a1-squashfs-sysupgrade.bin
Note that trunk does not include a web interface (luci) by default, but one can be installed: http://wiki.openwrt.org/doc/howto/luci.essentials
This device is using QCA9558 (ath9k) and QCA9882 (ath10k). The switch is AR8327.
On wikidevi: https://wikidevi.com/wiki/D-Link_DGL-5500_rev_A1