lkml.org 
[lkml]   [2019]   [Jan]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH] can: flexcan: fix timeout when set small bitrate
Date
> -----Original Message-----
> From: Joakim Zhang
> Sent: Thursday, January 31, 2019 5:37 PM
> To: mkl@pengutronix.de; linux-can@vger.kernel.org
> Cc: wg@grandegger.com; netdev@vger.kernel.org;
> linux-kernel@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>; Joakim
> Zhang <qiangqing.zhang@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.zhang@nxp.com>

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

Regards
Dong Aisheng

\
 
 \ /
  Last update: 2019-01-31 11:10    [W:0.063 / U:44.452 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site