[PATCH] wpa_supplicant: Enable HT40 support for AP mode

[Jouni Malinen]

On Mon, Jul 09, 2012 at 10:21:08AM +0530, Rajkumar Manoharan wrote:
> Right now HT40 mode is not enabled for AP/P2P GO mode in wpa_supplicant.
> If the HW is capable of 40MHz channel width and user specifies the
> secondary channel posision, lets enable the HT40 mode in wpa_s. This
> patch also enables HT40 support for P2P mode.
> 
> ap_ht40_mode : -1 -> HT40MINUS, 1 -> HT40PLUS

This looks quite confusing to use as a global parameter. The selection
between HT40- and HT40+ should really be based on the channel that ends
up getting used (e.g., cannot use HT40- on channel 36). The preferred
way of specifying plus vs. minus would be with the operation that
selects the channel (say, p2p_connect command). For a global parameter,
I would rather have just enable_ht40 0/1 and have the plus/minus part
figured out automatically based on which channel is going to be used.

> diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
> @@ -2231,10 +2231,8 @@ static int wpas_p2p_setup_channels(struct wpa_supplicant *wpa_s,
>  	struct p2p_oper_class_map op_class[] = {
>  		{ HOSTAPD_MODE_IEEE80211G, 81, 1, 13, 1, BW20 },
>  		{ HOSTAPD_MODE_IEEE80211G, 82, 14, 14, 1, BW20 },
> -#if 0 /* Do not enable HT40 on 2 GHz for now */
>  		{ HOSTAPD_MODE_IEEE80211G, 83, 1, 9, 1, BW40PLUS },
>  		{ HOSTAPD_MODE_IEEE80211G, 84, 5, 13, 1, BW40MINUS },
> -#endif

Why? 40 MHz channels on 2 GHz band were disabled on purpose and I would
like to keep this separate from the possibility of using 40 MHz channels
on 5 GHz.

-- 
Jouni Malinen                                            PGP id EFC895FA