Commit 52375446 authored by Marc Kleine-Budde's avatar Marc Kleine-Budde

can: bittiming: can_fixup_bittiming(): set effective tq

The can_fixup_bittiming() function is used to validate the
user-supplied low-level bit timing parameters and calculate the
bitrate prescaler (brp) from the requested time quanta (tq) and the
CAN clock of the controller.

can_fixup_bittiming() selects the best matching integer bit rate
prescaler, which may result in a different time quantum than the value
specified by the user.

Calculate the resulting time quantum and assign it so that the user
sees the effective time quantum.

Link: https://lore.kernel.org/all/20230202110854.2318594-4-mkl@pengutronix.deSigned-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 9cf670db
......@@ -40,6 +40,8 @@ static int can_fixup_bittiming(const struct net_device *dev, struct can_bittimin
bt->bitrate = priv->clock.freq / (bt->brp * can_bit_time(bt));
bt->sample_point = ((CAN_SYNC_SEG + tseg1) * 1000) / can_bit_time(bt);
bt->tq = DIV_U64_ROUND_CLOSEST(mul_u32_u32(bt->brp, NSEC_PER_SEC),
priv->clock.freq);
return 0;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment