[PATCH v2 12/12] can: f81604: fix {rx,tx}_errors statistics

[Dario Binacchi <dario.binacchi@amarulasolutions.com>]

The f81604_handle_can_bus_errors() function only incremented the receive
error counter and never the transmit error counter, even if the ECC_DIR
flag reported that an error had occurred during transmission. Increment
the receive/transmit error counter based on the value of the ECC_DIR
flag.

Fixes: 88da17436973 ("can: usb: f81604: add Fintek F81604 support")
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>

---

Changes in v2:
- Fix patches 7 through 12 to ensure that statistics are updated even
  if the allocation of skb fails.
- Add five new patches (i. e. 1-5), created during the further analysis
  of the code while correcting patches from the v1 series (i. e. 7-12).
- Update statistics even if skb allocation fails

 drivers/net/can/usb/f81604.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/net/can/usb/f81604.c b/drivers/net/can/usb/f81604.c
index bc0c8903fe77..e0cfa1460b0b 100644
--- a/drivers/net/can/usb/f81604.c
+++ b/drivers/net/can/usb/f81604.c
@@ -526,7 +526,6 @@ static void f81604_handle_can_bus_errors(struct f81604_port_priv *priv,
 		netdev_dbg(netdev, "bus error interrupt\n");
 
 		priv->can.can_stats.bus_error++;
-		stats->rx_errors++;
 
 		if (skb) {
 			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
@@ -548,10 +547,15 @@ static void f81604_handle_can_bus_errors(struct f81604_port_priv *priv,
 
 			/* set error location */
 			cf->data[3] = data->ecc & F81604_SJA1000_ECC_SEG;
+		}
 
-			/* Error occurred during transmission? */
-			if ((data->ecc & F81604_SJA1000_ECC_DIR) == 0)
+		/* Error occurred during transmission? */
+		if ((data->ecc & F81604_SJA1000_ECC_DIR) == 0) {
+			stats->tx_errors++;
+			if (skb)
 				cf->data[2] |= CAN_ERR_PROT_TX;
+		} else {
+			stats->rx_errors++;
 		}
 
 		set_bit(F81604_CLEAR_ECC, &priv->clear_flags);
-- 
2.43.0