Kindly Ping... Reviewed-by: Dong Aisheng <aisheng.d...@nxp.com>
Best Regards, Joakim Zhang > -----Original Message----- > From: Joakim Zhang > Sent: 2019年1月31日 17:37 > To: m...@pengutronix.de; linux-...@vger.kernel.org > Cc: w...@grandegger.com; net...@vger.kernel.org; > linux-kernel@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> > --- > drivers/net/can/flexcan.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index > 2bca867bcfaa..1f2b4db7da88 100644 > --- a/drivers/net/can/flexcan.c > +++ b/drivers/net/can/flexcan.c > @@ -166,7 +166,7 @@ > #define FLEXCAN_MB_CNT_LENGTH(x) (((x) & 0xf) << 16) > #define FLEXCAN_MB_CNT_TIMESTAMP(x) ((x) & 0xffff) > > -#define FLEXCAN_TIMEOUT_US (50) > +#define FLEXCAN_TIMEOUT_US (100) > > /* FLEXCAN hardware feature flags > * > -- > 2.17.1
