[PATCH 4.4 05/75] can: flexcan: assert FRZ bit in flexcan_chip_freeze()

[gregkh]

From: Greg Kroah-Hartman <gre...@linuxfoundation.org>

From: Joakim Zhang <qiangqing.zh...@nxp.com>

commit 449052cfebf624b670faa040245d3feed770d22f upstream.

Assert HALT bit to enter freeze mode, there is a premise that FRZ bit is
asserted. This patch asserts FRZ bit in flexcan_chip_freeze, although
the reset value is 1b'1. This is a prepare patch, later patch will
invoke flexcan_chip_freeze() to enter freeze mode, which polling freeze
mode acknowledge.

Fixes: b1aa1c7a2165b ("can: flexcan: fix transition from and to freeze mode in 
chip_{,un}freeze")
Link: https://lore.kernel.org/r/20210218110037.16591-2-qiangqing.zh...@nxp.com
Signed-off-by: Joakim Zhang <qiangqing.zh...@nxp.com>
Signed-off-by: Marc Kleine-Budde <m...@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/net/can/flexcan.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -383,7 +383,7 @@ static int flexcan_chip_freeze(struct fl
        u32 reg;
 
        reg = flexcan_read(&regs->mcr);
-       reg |= FLEXCAN_MCR_HALT;
+       reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT;
        flexcan_write(reg, &regs->mcr);
 
        while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))