> -----Original Message-----
> From: Joakim Zhang
> Sent: Thursday, January 31, 2019 5:37 PM
> To: m...@pengutronix.de; linux-...@vger.kernel.org
> Cc: w...@grandegger.com; netdev@vger.kernel.org;
> linux-ker...@vger.kernel.org; dl-linux-imx <linux-...@nxp.com>; Joakim
> Zhang <qiangqing.zh...@nxp.com>
> Subject: [PATCH] can: flexcan: fix timeout when set small bitrate
> 
> Current we can meet timeout issue when setting a small bitrate like 10000 as
> follows on i.MX6UL EVK board (ipg clock = 66MHZ, per clock = 30MHZ):
> root@imx6ul7d:~# ip link set can0 up type can bitrate 10000 A link change
> request failed with some changes committed already.
> Interface can0 may have been left with an inconsistent configuration, please
> check.
> RTNETLINK answers: Connection timed out
> 
> It is caused by calling of flexcan_chip_unfreeze() timeout.
> 
> Originally the code is using usleep_range(10, 20) for unfreeze operation, but
> the patch (8badd65 can: flexcan: avoid calling usleep_range from interrupt
> context) changed it into udelay(10) which is only a half delay of before,
> there're also some other delay changes.
> 
> After double to FLEXCAN_TIMEOUT_US to 100 can fix the issue.
> 
> Signed-off-by: Joakim Zhang <qiangqing.zh...@nxp.com>

Reviewed-by: Dong Aisheng <aisheng.d...@nxp.com>

Regards
Dong Aisheng

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