[PATCH 6.0 0244/1073] can: kvaser_usb_leaf: Set Warning state even without bus errors

Greg Kroah-Hartman
2022-12-28T15:27:12Z

From: Anssi Hannula <anssi.hannula@bitwise.fi>

[ Upstream commit df1b7af2761b935f63b4a53e789d41ed859edf61 ]

kvaser_usb_leaf_rx_error_update_can_state() sets error state according
to error counters when the hardware does not indicate a specific state
directly.

However, this is currently gated behind a check for
M16C_STATE_BUS_ERROR which does not always seem to be set when error
counters are increasing, and may not be set when error counters are
decreasing.

This causes the CAN_STATE_ERROR_WARNING state to not be set in some
cases even when appropriate.

Change the code to set error state from counters even without
M16C_STATE_BUS_ERROR.

The Error-Passive case seems superfluous as it is already set via
M16C_STATE_BUS_PASSIVE flag above, but it is kept for now.

Tested with 0bfd:0124 Kvaser Mini PCI Express 2xHS FW 4.18.778.

Fixes: 080f40a6fa28 ("can: kvaser_usb: Add support for Kvaser CAN/USB devices")
Tested-by: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://lore.kernel.org/all/20221010185237.319219-6-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../net/can/usb/kvaser_usb/kvaser_usb_leaf.c | 20 ++++++++-----------
1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
index 5d96ab85d04c..a6a26085bc15 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
@@ -961,20 +961,16 @@ kvaser_usb_leaf_rx_error_update_can_state(struct kvaser_usb_net_priv *priv,
new_state = CAN_STATE_BUS_OFF;
} else if (es->status & M16C_STATE_BUS_PASSIVE) {
new_state = CAN_STATE_ERROR_PASSIVE;
- } else if (es->status & M16C_STATE_BUS_ERROR) {
+ } else if ((es->status & M16C_STATE_BUS_ERROR) &&
+ cur_state >= CAN_STATE_BUS_OFF) {
/* Guard against spurious error events after a busoff */
- if (cur_state < CAN_STATE_BUS_OFF) {
- if (es->txerr >= 128 || es->rxerr >= 128)
- new_state = CAN_STATE_ERROR_PASSIVE;
- else if (es->txerr >= 96 || es->rxerr >= 96)
- new_state = CAN_STATE_ERROR_WARNING;
- else if (cur_state > CAN_STATE_ERROR_ACTIVE)
- new_state = CAN_STATE_ERROR_ACTIVE;
- }
- }
-
- if (!es->status)
+ } else if (es->txerr >= 128 || es->rxerr >= 128) {
+ new_state = CAN_STATE_ERROR_PASSIVE;
+ } else if (es->txerr >= 96 || es->rxerr >= 96) {
+ new_state = CAN_STATE_ERROR_WARNING;
+ } else {
new_state = CAN_STATE_ERROR_ACTIVE;
+ }

if (new_state != cur_state) {
tx_state = (es->txerr >= es->rxerr) ? new_state : 0;
--
2.35.1