Commit 5988bf73 authored by Marc Kleine-Budde's avatar Marc Kleine-Budde
Browse files

can: bittiming: factor out can_sjw_set_default() and can_sjw_check() 

Factor out the functionality of assigning a SJW default value into
can_sjw_set_default() and the checking the SJW limits into
can_sjw_check().

This functions will be improved and called from a different function
in the following patches.

Link: https://lore.kernel.org/all/20230202110854.2318594-11-mkl@pengutronix.de


Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 286c0e09

drivers/net/can/dev/bittiming.c

+26 −4
Original line number Diff line number Diff line
@@ -6,6 +6,24 @@ 


#include <linux/can/dev.h>



void can_sjw_set_default(struct can_bittiming *bt)

{

	if (bt->sjw)

		return;



	/* If user space provides no sjw, use 1 as default */

	bt->sjw = 1;

}



int can_sjw_check(const struct net_device *dev, const struct can_bittiming *bt,

		  const struct can_bittiming_const *btc, struct netlink_ext_ack *extack)

{

	if (bt->sjw > btc->sjw_max)

		return -ERANGE;



	return 0;

}



/* Checks the validity of the specified bit-timing parameters prop_seg,

 * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate

 * prescaler value brp. You can find more information in the header
@@ -18,12 +36,16 @@ static int can_fixup_bittiming(const struct net_device *dev, struct can_bittimin 
	const struct can_priv *priv = netdev_priv(dev);

	unsigned int tseg1;

	u64 brp64;

	int err;



	can_sjw_set_default(bt);



	err = can_sjw_check(dev, bt, btc, extack);

	if (err)

		return err;



	tseg1 = bt->prop_seg + bt->phase_seg1;

	if (!bt->sjw)

		bt->sjw = 1;

	if (bt->sjw > btc->sjw_max ||

	    tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||

	if (tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||

	    bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)

		return -ERANGE;

include/linux/can/bittiming.h

+5 −0
Original line number Diff line number Diff line
@@ -138,6 +138,11 @@ can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const, 
}

#endif /* CONFIG_CAN_CALC_BITTIMING */



void can_sjw_set_default(struct can_bittiming *bt);



int can_sjw_check(const struct net_device *dev, const struct can_bittiming *bt,

		  const struct can_bittiming_const *btc, struct netlink_ext_ack *extack);



int can_get_bittiming(const struct net_device *dev, struct can_bittiming *bt,

		      const struct can_bittiming_const *btc,

		      const u32 *bitrate_const,