can: sun4i_can: sun4i_can_err(): fix {rx,tx}_errors statistics

[ Upstream commit 595a819 ]

The sun4i_can_err() function only incremented the receive error counter
and never the transmit error counter, even if the STA_ERR_DIR flag
reported that an error had occurred during transmission.

Increment the receive/transmit error counter based on the value of the
STA_ERR_DIR flag.

Fixes: 0738eff ("can: Allwinner A10/A20 CAN Controller support - Kernel module")
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://patch.msgid.link/20241122221650.633981-11-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/can/sun4i_can.c

@@ -580,11 +580,9 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 		/* bus error interrupt */
 		netdev_dbg(dev, "bus error interrupt\n");
 		priv->can.can_stats.bus_error++;
-		stats->rx_errors++;
+		ecc = readl(priv->base + SUN4I_REG_STA_ADDR);
 
 		if (likely(skb)) {
-			ecc = readl(priv->base + SUN4I_REG_STA_ADDR);
-
 			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 
 			switch (ecc & SUN4I_STA_MASK_ERR) {
@@ -602,9 +600,15 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 					       >> 16;
 				break;
 			}
-			/* error occurred during transmission? */
-			if ((ecc & SUN4I_STA_ERR_DIR) == 0)
+		}
+
+		/* error occurred during transmission? */
+		if ((ecc & SUN4I_STA_ERR_DIR) == 0) {
+			if (likely(skb))
 				cf->data[2] |= CAN_ERR_PROT_TX;
+			stats->tx_errors++;
+		} else {
+			stats->rx_errors++;
 		}
 	}
 	if (isrc & SUN4I_INT_ERR_PASSIVE) {