mac80211/drivers: rewrite the rate control API

So after the previous changes we were still unhappy with how
convoluted the API is and decided to make things simpler for
everybody. This completely changes the rate control API, now
taking into account 802.11n with MCS rates and more control,
most drivers don't support that though.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 29 insertions, 2 deletions

diff --git a/drivers/net/wireless/b43legacy/pio.c b/drivers/net/wireless/b43legacy/pio.c
index a86c7647fa2d..746d5361bba0 100644
--- a/drivers/net/wireless/b43legacy/pio.c
+++ b/drivers/net/wireless/b43legacy/pio.c
@@ -491,6 +491,7 @@ void b43legacy_pio_handle_txstatus(struct b43legacy_wldev *dev,
 	struct b43legacy_pioqueue *queue;
 	struct b43legacy_pio_txpacket *packet;
 	struct ieee80211_tx_info *info;
+	int retry_limit;
 
 	queue = parse_cookie(dev, status->cookie, &packet);
 	B43legacy_WARN_ON(!queue);
@@ -503,11 +504,37 @@ void b43legacy_pio_handle_txstatus(struct b43legacy_wldev *dev,
 				sizeof(struct b43legacy_txhdr_fw3));
 
 	info = IEEE80211_SKB_CB(packet->skb);
-	memset(&info->status, 0, sizeof(info->status));
+
+	/* preserve the confiured retry limit before clearing the status
+	 * The xmit function has overwritten the rc's value with the actual
+	 * retry limit done by the hardware */
+	retry_limit = info->status.rates[0].count;
+	ieee80211_tx_info_clear_status(info);
 
 	if (status->acked)
 		info->flags |= IEEE80211_TX_STAT_ACK;
-	info->status.retry_count = status->frame_count - 1;
+
+	if (status->rts_count > dev->wl->hw->conf.short_frame_max_tx_count) {
+		/*
+		 * If the short retries (RTS, not data frame) have exceeded
+		 * the limit, the hw will not have tried the selected rate,
+		 * but will have used the fallback rate instead.
+		 * Don't let the rate control count attempts for the selected
+		 * rate in this case, otherwise the statistics will be off.
+		 */
+		info->status.rates[0].count = 0;
+		info->status.rates[1].count = status->frame_count;
+	} else {
+		if (status->frame_count > retry_limit) {
+			info->status.rates[0].count = retry_limit;
+			info->status.rates[1].count = status->frame_count -
+					retry_limit;
+
+		} else {
+			info->status.rates[0].count = status->frame_count;
+			info->status.rates[1].idx = -1;
+		}
+	}
 	ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb);
 	packet->skb = NULL;