From 4313b5e1d6f30ef681c0027b907ecf921cd74420 Mon Sep 17 00:00:00 2001 From: Roman Fietze 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 BugLink: http://bugs.launchpad.net/bugs/1814813 commit 393753b217f05474e714aea36c37501546ed1202 upstream. 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 Cc: linux-stable Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman Signed-off-by: Kamal Mostafa Signed-off-by: Stefan Bader --- drivers/net/can/m_can/m_can.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c index 5d4e61741476..ca3fa82316c2 100644 --- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -1073,7 +1073,8 @@ 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) -- 2.39.5