[PATCH net 08/20] can: ctucanfd: use self-test mode for PRESUME_ACK

Marc Kleine-Budde <[email protected]> Wed, 29 Jul 2026 12:12:48 +0200
Newsgroups org.kernel.vger.linux-can,org.kernel.vger.netdev
Message-ID <[email protected]>
From: Avi Weiss <[email protected]>

Use self-test mode for CAN_CTRLMODE_PRESUME_ACK so transmitted
frames can complete without receiving an ACK.

ACK forbidden mode prevents the controller from acknowledging
received frames and does not implement the presume-ack behavior.

Fixes: 2dcb8e8782d8 ("can: ctucanfd: add support for CTU CAN FD open-source IP core - bus independent part.")
Signed-off-by: Avi Weiss <[email protected]>
Acked-by: Pavel Pisa <[email protected]>
Link: https://patch.msgid.link/[email protected]
Cc: [email protected]
Signed-off-by: Marc Kleine-Budde <[email protected]>
---
 drivers/net/can/ctucanfd/ctucanfd_base.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/ctucanfd/ctucanfd_base.c b/drivers/net/can/ctucanfd/ctucanfd_base.c
index 10ebcc13ea65..07d4aa43c700 100644
--- a/drivers/net/can/ctucanfd/ctucanfd_base.c
+++ b/drivers/net/can/ctucanfd/ctucanfd_base.c
@@ -340,8 +340,8 @@ static void ctucan_set_mode(struct ctucan_priv *priv, const struct can_ctrlmode
 			(mode_reg & ~REG_MODE_FDE);
 
 	mode_reg = (mode->flags & CAN_CTRLMODE_PRESUME_ACK) ?
-			(mode_reg | REG_MODE_ACF) :
-			(mode_reg & ~REG_MODE_ACF);
+			(mode_reg | REG_MODE_STM) :
+			(mode_reg & ~REG_MODE_STM);
 
 	mode_reg = (mode->flags & CAN_CTRLMODE_FD_NON_ISO) ?
 			(mode_reg | REG_MODE_NISOFD) :
-- 
2.53.0