Re: [PATCH] mac80211: support RX_FLAG_MACTIME_END

[Johannes Berg <johannes@sipsolutions.net>]

On Mon, 2012-11-12 at 10:38 -0800, Thomas Pedersen wrote:

> +	if (ieee80211_have_rx_timestamp(rx_status))
> +		/* time when timestamp field was received */
> +		t_r = ieee80211_calculate_rx_timestamp(local, rx_status,
> +						       24 + 12 +
> +						       elems->total_len + 4,
> +						       24);

This doesn't seem quite right, the FCS isn't accounted for correctly?

I think it might be wortwhile to pass the SKB to the function instead of
rx_status though, then it could get skb->len and check whether or not
FCS was before the timestamp (which, btw, you should mention in the
documentation for the new flag!)

And then I suspect the check for IEEE80211_HW_RX_INCLUDES_FCS is also
incorrect -- even if the driver didn't report the FCS maybe the
timestamping semantic was such that it was after the FCS?

This seems to need a little fixing up, but other than that looks good.

johannes