netdev - [PATCH 32/32] staging: wfx: remove hack about tx

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Date:   Wed,  1 Apr 2020 13:04:05 +0200
From:   Jerome Pouiller <Jerome.Pouiller@...abs.com>
To:     devel@...verdev.osuosl.org, linux-wireless@...r.kernel.org
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Kalle Valo <kvalo@...eaurora.org>,
        "David S . Miller" <davem@...emloft.net>,
        Jérôme Pouiller 
        <jerome.pouiller@...abs.com>
Subject: [PATCH 32/32] staging: wfx: remove hack about tx_rate policies

From: Jérôme Pouiller <jerome.pouiller@...abs.com>

Current code contains a weird hack to avoid switch from 54Mbps CTS to
1Mbps. However, we have not been able to reproduce the problem and
hardware team don't know any defect of this kind. So, it seems this hack
is no more necessary.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@...abs.com>
---
 drivers/staging/wfx/data_tx.c | 53 -----------------------------------
 1 file changed, 53 deletions(-)

diff --git a/drivers/staging/wfx/data_tx.c b/drivers/staging/wfx/data_tx.c
index 1d9a8089f3d3..93ed0ed63bb2 100644
--- a/drivers/staging/wfx/data_tx.c
+++ b/drivers/staging/wfx/data_tx.c
@@ -51,59 +51,6 @@ static void wfx_tx_policy_build(struct wfx_vif *wvif, struct tx_policy *policy,
 		if (rates[i].idx < 0)
 			break;
 	count = i;
-
-	/* HACK!!! Device has problems (at least) switching from
-	 * 54Mbps CTS to 1Mbps. This switch takes enormous amount
-	 * of time (100-200 ms), leading to valuable throughput drop.
-	 * As a workaround, additional g-rates are injected to the
-	 * policy.
-	 */
-	if (count == 2 && !(rates[0].flags & IEEE80211_TX_RC_MCS) &&
-	    rates[0].idx > 4 && rates[0].count > 2 &&
-	    rates[1].idx < 2) {
-		int mid_rate = (rates[0].idx + 4) >> 1;
-
-		/* Decrease number of retries for the initial rate */
-		rates[0].count -= 2;
-
-		if (mid_rate != 4) {
-			/* Keep fallback rate at 1Mbps. */
-			rates[3] = rates[1];
-
-			/* Inject 1 transmission on lowest g-rate */
-			rates[2].idx = 4;
-			rates[2].count = 1;
-			rates[2].flags = rates[1].flags;
-
-			/* Inject 1 transmission on mid-rate */
-			rates[1].idx = mid_rate;
-			rates[1].count = 1;
-
-			/* Fallback to 1 Mbps is a really bad thing,
-			 * so let's try to increase probability of
-			 * successful transmission on the lowest g rate
-			 * even more
-			 */
-			if (rates[0].count >= 3) {
-				--rates[0].count;
-				++rates[2].count;
-			}
-
-			/* Adjust amount of rates defined */
-			count += 2;
-		} else {
-			/* Keep fallback rate at 1Mbps. */
-			rates[2] = rates[1];
-
-			/* Inject 2 transmissions on lowest g-rate */
-			rates[1].idx = 4;
-			rates[1].count = 2;
-
-			/* Adjust amount of rates defined */
-			count += 1;
-		}
-	}
-
 	for (i = 0; i < IEEE80211_TX_MAX_RATES; ++i) {
 		int rateid;
 		u8 count;
-- 
2.25.1