@@ -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;
@@ -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,
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: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/can/dev/bittiming.c | 30 ++++++++++++++++++++++++++---- include/linux/can/bittiming.h | 5 +++++ 2 files changed, 31 insertions(+), 4 deletions(-)