[PATCH v2] hostapd: add Transmit Power Envelope IE

[Jouni Malinen]

On Mon, Nov 23, 2015 at 06:40:26PM +0530, Rajkumar Manoharan wrote:
> Add Transmit Power Envelope element defined in
> IEEE P802.11-REVmc/D4.3, 8.4.2.161.

Thanks, applied.

> diff --git a/src/ap/ieee802_11_vht.c b/src/ap/ieee802_11_vht.c
> +u8 * hostapd_eid_vht_txpwr_env(struct hostapd_data *hapd, u8 *eid)

> +	max_tx_power = chan->max_tx_power - local_pwr_constraint;
> +
> +	/*
> +	 * Local Maximum Transmit power is encoded as 2's complement
> +	 * with a 0.5 dB step
> +	 */
> +	max_tx_power = ~(max_tx_power * 2) + 1;

Though, this does not look correct.. That would mess up positive values
pretty badly. I think I fixed this, but anyway, please take a look at
send a patch to update this, if needed.

> +	*eid++ = WLAN_EID_VHT_TRANSMIT_POWER_ENVELOPE;
> +	*eid++ = 4;

That length value is not correct since this is now variable length:

> +	/*
> +	 * Max Transmit Power count and
> +	 * Max Transmit Power units = 0 (EIRP)
> +	 */
> +	*eid++ = tx_pwr_count;
> +
> +	i = 0;
> +	while (i++ <= tx_pwr_count)
> +		*eid++ = max_tx_power;

Here.. Fixed the length field to match.
 
-- 
Jouni Malinen                                            PGP id EFC895FA