Commit 82e4861c authored Nov 30, 2022 by Frank Jungclaus Committed by sanglipeng Jul 26, 2023

can: esd_usb: Allow REC and TEC to return to zero

stable inclusion
from stable-v5.10.159
commit 4fd6f84e0a0c432d1acc56b7ae76e7676587081d
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7NTXH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4fd6f84e0a0c432d1acc56b7ae76e7676587081d



--------------------------------

[ Upstream commit 918ee491 ]

We don't get any further EVENT from an esd CAN USB device for changes
on REC or TEC while those counters converge to 0 (with ecc == 0). So
when handling the "Back to Error Active"-event force txerr = rxerr =
0, otherwise the berr-counters might stay on values like 95 forever.

Also, to make life easier during the ongoing development a
netdev_dbg() has been introduced to allow dumping error events send by
an esd CAN USB device.

Fixes: 96d8e903 ("can: Add driver for esd CAN-USB/2 device")
Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
Link: https://lore.kernel.org/all/20221130202242.3998219-2-frank.jungclaus@esd.eu


Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>

parent 3208e0ec

drivers/net/can/usb/esd_usb2.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -227,6 +227,10 @@ static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
		u8 rxerr = msg->msg.rx.data[2];
		u8 txerr = msg->msg.rx.data[3];

		netdev_dbg(priv->netdev,
		"CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
		msg->msg.rx.dlc, state, ecc, rxerr, txerr);

		skb = alloc_can_err_skb(priv->netdev, &cf);
		if (skb == NULL) {
		stats->rx_dropped++;
		@@ -253,6 +257,8 @@ static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
		break;
		default:
		priv->can.state = CAN_STATE_ERROR_ACTIVE;
		txerr = 0;
		rxerr = 0;
		break;
		}
		} else {