can: netlink: make can_tdc_changelink() FD agnostic

can_tdc_changelink() needs to access can_priv->fd making it
specific to CAN FD. Change the function parameter from struct can_priv
to struct data_bittiming_params. This way, the function becomes CAN FD
agnostic and can be reused later on for the CAN XL TDC.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-9-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Author: vincent-mailhol

drivers/net/can/dev/netlink.c

@@ -172,12 +172,13 @@ static int can_validate(struct nlattr *tb[], struct nlattr *data[],
 	return 0;
 }
 
-static int can_tdc_changelink(struct can_priv *priv, const struct nlattr *nla,
+static int can_tdc_changelink(struct data_bittiming_params *dbt_params,
+			      const struct nlattr *nla,
 			      struct netlink_ext_ack *extack)
 {
 	struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1];
 	struct can_tdc tdc = { 0 };
-	const struct can_tdc_const *tdc_const = priv->fd.tdc_const;
+	const struct can_tdc_const *tdc_const = dbt_params->tdc_const;
 	int err;
 
 	if (!tdc_const)
@@ -215,7 +216,7 @@ static int can_tdc_changelink(struct can_priv *priv, const struct nlattr *nla,
 		tdc.tdcf = tdcf;
 	}
 
-	priv->fd.tdc = tdc;
+	dbt_params->tdc = tdc;
 
 	return 0;
 }
@@ -382,8 +383,8 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 		memset(&priv->fd.tdc, 0, sizeof(priv->fd.tdc));
 		if (data[IFLA_CAN_TDC]) {
 			/* TDC parameters are provided: use them */
-			err = can_tdc_changelink(priv, data[IFLA_CAN_TDC],
-						 extack);
+			err = can_tdc_changelink(&priv->fd,
+						 data[IFLA_CAN_TDC], extack);
 			if (err) {
 				priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
 				return err;