[PATCH v2 net-next 09/13] net: stmmac: ethtool: Let user configure TX coalesce without RIWT

[Jose Abreu <Jose.Abreu@synopsys.com>]

When RX Watchdog is disabled its currently not possible to configure TX
coalesce settings. Let user configure it anyway.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>

---
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Jose Abreu <joabreu@synopsys.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: netdev@vger.kernel.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 .../net/ethernet/stmicro/stmmac/stmmac_ethtool.c    | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
index 1c450105e5a6..1a768837ca72 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
@@ -746,8 +746,15 @@ static int stmmac_set_coalesce(struct net_device *dev,
 	    (ec->tx_max_coalesced_frames_high) || (ec->rate_sample_interval))
 		return -EOPNOTSUPP;
 
-	if (ec->rx_coalesce_usecs == 0)
-		return -EINVAL;
+	if (priv->use_riwt && (ec->rx_coalesce_usecs > 0)) {
+		rx_riwt = stmmac_usec2riwt(ec->rx_coalesce_usecs, priv);
+
+		if ((rx_riwt > MAX_DMA_RIWT) || (rx_riwt < MIN_DMA_RIWT))
+			return -EINVAL;
+
+		priv->rx_riwt = rx_riwt;
+		stmmac_rx_watchdog(priv, priv->ioaddr, priv->rx_riwt, rx_cnt);
+	}
 
 	if ((ec->tx_coalesce_usecs == 0) &&
 	    (ec->tx_max_coalesced_frames == 0))
@@ -757,20 +764,10 @@ static int stmmac_set_coalesce(struct net_device *dev,
 	    (ec->tx_max_coalesced_frames > STMMAC_TX_MAX_FRAMES))
 		return -EINVAL;
 
-	rx_riwt = stmmac_usec2riwt(ec->rx_coalesce_usecs, priv);
-
-	if ((rx_riwt > MAX_DMA_RIWT) || (rx_riwt < MIN_DMA_RIWT))
-		return -EINVAL;
-	else if (!priv->use_riwt)
-		return -EOPNOTSUPP;
-
 	/* Only copy relevant parameters, ignore all others. */
 	priv->tx_coal_frames = ec->tx_max_coalesced_frames;
 	priv->tx_coal_timer = ec->tx_coalesce_usecs;
 	priv->rx_coal_frames = ec->rx_max_coalesced_frames;
-	priv->rx_riwt = rx_riwt;
-	stmmac_rx_watchdog(priv, priv->ioaddr, priv->rx_riwt, rx_cnt);
-
 	return 0;
 }
 
-- 
2.7.4