HW retransmissions

[Steger, Marco]

Dear all,

I'm setting up a real testbed for validation IEEE802.11s nodes for different automotive scenarios. I'm using BeagleBone boards running Debian and the TL-WN722N stick (ATH9k_htc). For the evaluation I need a lot of different parameters of the nodes and the links. 

All the 11s (mesh) specific information I collect in the Linux kernel module mac80211.ko (I've added some debug function to write data blobs using debugfs). I can use 
	* ieee80211_tx_info
	* ieee80211_rx_status
	* sta_info
	* mesh_sta

And so on. With that I get a lot of useful and important parameters. With "(txinfo->flags & IEEE80211_TX_STAT_ACK), where txinfo is a ieee80211_tx_info* "  I can check if the transmission we successful or not.  But I think I'm still missing one: The retransmission on the HW and I hope you can help me a little bit with that:
	* Are there retransmissions on the HW? (Directly done by the ATH9k_htc). 
	* If yes, how can I get the number of retransmission for every frame? Is this possible? Maybe this is already somewhere hidden in the structs mentioned above.
	* If there are retransmission, is there a way to turn it off for testing purposes?

Would be really great if you can help me with that!

Thanks in advance!

Best regards,
Marco