I would recommend reading Chapter 6 : WMM and QoS section of the 802.11n VRD http://www.arubanetworks.com/pdf/technology/VRD_80211n_networks_v8.pdf
If the traffic is properly tagged the Aruba APs convert DSCP markings to WMM and vice-versa. If the traffic is untagged then you can use ACLs to enforce proper tagging. Depending on the forwarding mode ACLs might be processed at the controller or at the AP. The SSID profile also specifies the default DSCP-WMM mapping which can be altered. QoS settings are not AP dependent.
Regards,
Sathya