Re: [PATCH v5 5/7] can: netlink: add interface for CAN-FD Transmitter Delay Compensation (TDC)

+static int can_tdc_changelink(struct net_device *dev, const struct nlattr *nla,
+			      struct netlink_ext_ack *extack)
+{
+	struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1];
+	struct can_priv *priv = netdev_priv(dev);
+	struct can_tdc *tdc = &priv->tdc;
+	const struct can_tdc_const *tdc_const = priv->tdc_const;
+	int err;
+
+	if (!tdc_const || !can_tdc_is_enabled(priv))
+		return -EOPNOTSUPP;
+
+	if (dev->flags & IFF_UP)
+		return -EBUSY;
+
+	err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX, nla,
+			       can_tdc_policy, extack);
+	if (err)
+		return err;
+
+	if (tb_tdc[IFLA_CAN_TDC_TDCV]) {
+		u32 tdcv = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCV]);
+
+		if (tdcv < tdc_const->tdcv_min || tdcv > tdc_const->tdcv_max)
+			return -EINVAL;
+
+		tdc->tdcv = tdcv;

+	}
+
+	if (tb_tdc[IFLA_CAN_TDC_TDCO]) {
+		u32 tdco = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCO]);
+
+		if (tdco < tdc_const->tdco_min || tdco > tdc_const->tdco_max)
+			return -EINVAL;
+
+		tdc->tdco = tdco;
+	}
+
+	if (tb_tdc[IFLA_CAN_TDC_TDCF]) {
+		u32 tdcf = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCF]);
+
+		if (tdcf < tdc_const->tdcf_min || tdcf > tdc_const->tdcf_max)
+			return -EINVAL;
+
+		tdc->tdcf = tdcf;
+	}
+
+	return 0;
+}