The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 393753b217f05474e714aea36c37501546ed1202 Mon Sep 17 00:00:00 2001
From: Roman Fietze <roman.fietze@xxxxxxxxxxxxx>
Date: Wed, 11 Jul 2018 15:36:14 +0200
Subject: [PATCH] can: m_can.c: fix setup of CCCR register: clear CCCR NISO bit
before checking can.ctrlmode
Inside m_can_chip_config(), when setting up the new value of the CCCR,
the CCCR_NISO bit is not cleared like the others, CCCR_TEST, CCCR_MON,
CCCR_BRSE and CCCR_FDOE, before checking the can.ctrlmode bits for
CAN_CTRLMODE_FD_NON_ISO.
This way once the controller was configured for CAN_CTRLMODE_FD_NON_ISO,
this mode could never be cleared again.
This fix is only relevant for controllers with version 3.1.x or 3.2.x.
Older versions do not support NISO.
Signed-off-by: Roman Fietze <roman.fietze@xxxxxxxxxxxxx>
Cc: linux-stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index b397a33f3d32..8e2b7f873c4d 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -1109,7 +1109,8 @@ static void m_can_chip_config(struct net_device *dev)
} else {
/* Version 3.1.x or 3.2.x */
- cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE);
+ cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE |
+ CCCR_NISO);
/* Only 3.2.x has NISO Bit implemented */
if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
