Merge tag 'linux-can-next-for-6.18-20250924' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2025-09-25

this is a pull request of 48 patches for net-next/main, which
supersedes tags/linux-can-next-for-6.18-20250923.

The 1st patch is by Xichao Zhao and converts ns_to_ktime() to
us_to_ktime() in the m_can driver.

Vincent Mailhol contributes 2 patches: Updating the MAINTAINERS and
mailmap files to Vincent's new email address and sorting the includes
in the CAN helper library alphabeticaly.

Stéphane Grosjean's patch modifies all peak CAN drivers and the
mailmap to reflect Stéphane's new email address.

4 patches by Biju Das update the CAN-FD handling in the rcar_canfd
driver.

Followed by 11 patches by Geert Uytterhoeven updating and improving
the rcar_can driver.

Stefan Mätje contributes 2 patches for the esd_usb driver updating the
error messages.

The next 3 patch series are all by Vincent Mailhol: 3 patches to
optimize the size of struct raw_sock and struct uniqframe. 4 patches
which rework the CAN MTU logic as preparation for CAN-XL interfaces.
And finally 20 patches that prepare and refactor the CAN netlink code
for the upcoming CAN-XL support.

* tag 'linux-can-next-for-6.18-20250924' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next: (48 commits)
  can: netlink: add userland error messages
  can: dev: add can_get_ctrlmode_str()
  can: calc_bittiming: make can_calc_tdco() FD agnostic
  can: netlink: make can_tdc_fill_info() FD agnostic
  can: netlink: add can_bitrate_const_fill_info()
  can: netlink: add can_bittiming_const_fill_info()
  can: netlink: add can_bittiming_fill_info()
  can: netlink: add can_data_bittiming_get_size()
  can: netlink: make can_tdc_get_size() FD agnostic
  can: netlink: add can_ctrlmode_changelink()
  can: netlink: add can_dtb_changelink()
  can: netlink: make can_tdc_changelink() FD agnostic
  can: netlink: remove useless check in can_tdc_changelink()
  can: netlink: refactor CAN_CTRLMODE_TDC_{AUTO,MANUAL} flag reset logic
  can: netlink: add can_validate_databittiming()
  can: netlink: add can_validate_tdc()
  can: netlink: refactor can_validate_bittiming()
  can: netlink: document which symbols are FD specific
  can: dev: make can_get_relative_tdco() FD agnostic and move it to bittiming.h
  can: dev: move struct data_bittiming_params to linux/can/bittiming.h
  ...
====================

Link: https://patch.msgid.link/20250925121332.848157-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 373 insertions, 219 deletions

diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index d9f6ab3efb97..0591406b6f32 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -36,116 +36,245 @@ static const struct nla_policy can_tdc_policy[IFLA_CAN_TDC_MAX + 1] = {
 	[IFLA_CAN_TDC_TDCF] = { .type = NLA_U32 },
 };
 
-static int can_validate_bittiming(const struct can_bittiming *bt,
-				  struct netlink_ext_ack *extack)
+static int can_validate_bittiming(struct nlattr *data[],
+				  struct netlink_ext_ack *extack,
+				  int ifla_can_bittiming)
 {
+	struct can_bittiming *bt;
+
+	if (!data[ifla_can_bittiming])
+		return 0;
+
+	static_assert(__alignof__(*bt) <= NLA_ALIGNTO);
+	bt = nla_data(data[ifla_can_bittiming]);
+
 	/* sample point is in one-tenth of a percent */
 	if (bt->sample_point >= 1000) {
 		NL_SET_ERR_MSG(extack, "sample point must be between 0 and 100%");
-
 		return -EINVAL;
 	}
 
 	return 0;
 }
 
-static int can_validate(struct nlattr *tb[], struct nlattr *data[],
-			struct netlink_ext_ack *extack)
+static int can_validate_tdc(struct nlattr *data_tdc,
+			    struct netlink_ext_ack *extack, u32 tdc_flags)
 {
-	bool is_can_fd = false;
+	bool tdc_manual = tdc_flags & CAN_CTRLMODE_TDC_MANUAL_MASK;
+	bool tdc_auto = tdc_flags & CAN_CTRLMODE_TDC_AUTO_MASK;
+	int err;
+
+	if (tdc_auto && tdc_manual) {
+		NL_SET_ERR_MSG(extack,
+			       "TDC manual and auto modes are mutually exclusive");
+		return -EOPNOTSUPP;
+	}
+
+	/* If one of the CAN_CTRLMODE_TDC_* flag is set then TDC
+	 * must be set and vice-versa
+	 */
+	if ((tdc_auto || tdc_manual) && !data_tdc) {
+		NL_SET_ERR_MSG(extack, "TDC parameters are missing");
+		return -EOPNOTSUPP;
+	}
+	if (!(tdc_auto || tdc_manual) && data_tdc) {
+		NL_SET_ERR_MSG(extack, "TDC mode (auto or manual) is missing");
+		return -EOPNOTSUPP;
+	}
+
+	/* If providing TDC parameters, at least TDCO is needed. TDCV
+	 * is needed if and only if CAN_CTRLMODE_TDC_MANUAL is set
+	 */
+	if (data_tdc) {
+		struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1];
+
+		err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX,
+				       data_tdc, can_tdc_policy, extack);
+		if (err)
+			return err;
+
+		if (tb_tdc[IFLA_CAN_TDC_TDCV]) {
+			if (tdc_auto) {
+				NL_SET_ERR_MSG(extack,
+					       "TDCV is incompatible with TDC auto mode");
+				return -EOPNOTSUPP;
+			}
+		} else {
+			if (tdc_manual) {
+				NL_SET_ERR_MSG(extack,
+					       "TDC manual mode requires TDCV");
+				return -EOPNOTSUPP;
+			}
+		}
+
+		if (!tb_tdc[IFLA_CAN_TDC_TDCO]) {
+			NL_SET_ERR_MSG(extack, "TDCO is missing");
+			return -EOPNOTSUPP;
+		}
+	}
+
+	return 0;
+}
+
+static int can_validate_databittiming(struct nlattr *data[],
+				      struct netlink_ext_ack *extack,
+				      int ifla_can_data_bittiming, u32 flags)
+{
+	struct nlattr *data_tdc;
+	const char *type;
+	u32 tdc_flags;
+	bool is_on;
 	int err;
 
 	/* Make sure that valid CAN FD configurations always consist of
 	 * - nominal/arbitration bittiming
 	 * - data bittiming
 	 * - control mode with CAN_CTRLMODE_FD set
-	 * - TDC parameters are coherent (details below)
+	 * - TDC parameters are coherent (details in can_validate_tdc())
 	 */
 
+	if (ifla_can_data_bittiming == IFLA_CAN_DATA_BITTIMING) {
+		data_tdc = data[IFLA_CAN_TDC];
+		tdc_flags = flags & CAN_CTRLMODE_FD_TDC_MASK;
+		is_on = flags & CAN_CTRLMODE_FD;
+		type = "FD";
+	} else {
+		return -EOPNOTSUPP; /* Place holder for CAN XL */
+	}
+
+	if (is_on) {
+		if (!data[IFLA_CAN_BITTIMING] || !data[ifla_can_data_bittiming]) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "Provide both nominal and %s data bittiming",
+					   type);
+			return -EOPNOTSUPP;
+		}
+	} else {
+		if (data[ifla_can_data_bittiming]) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "%s data bittiming requires CAN %s",
+					   type, type);
+			return -EOPNOTSUPP;
+		}
+		if (data_tdc) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "%s TDC requires CAN %s",
+					   type, type);
+			return -EOPNOTSUPP;
+		}
+	}
+
+	err = can_validate_bittiming(data, extack, ifla_can_data_bittiming);
+	if (err)
+		return err;
+
+	err = can_validate_tdc(data_tdc, extack, tdc_flags);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int can_validate(struct nlattr *tb[], struct nlattr *data[],
+			struct netlink_ext_ack *extack)
+{
+	u32 flags = 0;
+	int err;
+
 	if (!data)
 		return 0;
 
 	if (data[IFLA_CAN_CTRLMODE]) {
 		struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
-		u32 tdc_flags = cm->flags & CAN_CTRLMODE_FD_TDC_MASK;
 
-		is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
+		flags = cm->flags & cm->mask;
+	}
 
-		/* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually exclusive */
-		if (tdc_flags == CAN_CTRLMODE_FD_TDC_MASK)
-			return -EOPNOTSUPP;
-		/* If one of the CAN_CTRLMODE_TDC_* flag is set then
-		 * TDC must be set and vice-versa
-		 */
-		if (!!tdc_flags != !!data[IFLA_CAN_TDC])
-			return -EOPNOTSUPP;
-		/* If providing TDC parameters, at least TDCO is
-		 * needed. TDCV is needed if and only if
-		 * CAN_CTRLMODE_TDC_MANUAL is set
-		 */
-		if (data[IFLA_CAN_TDC]) {
-			struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1];
+	err = can_validate_bittiming(data, extack, IFLA_CAN_BITTIMING);
+	if (err)
+		return err;
 
-			err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX,
-					       data[IFLA_CAN_TDC],
-					       can_tdc_policy, extack);
-			if (err)
-				return err;
+	err = can_validate_databittiming(data, extack,
+					 IFLA_CAN_DATA_BITTIMING, flags);
+	if (err)
+		return err;
 
-			if (tb_tdc[IFLA_CAN_TDC_TDCV]) {
-				if (tdc_flags & CAN_CTRLMODE_TDC_AUTO)
-					return -EOPNOTSUPP;
-			} else {
-				if (tdc_flags & CAN_CTRLMODE_TDC_MANUAL)
-					return -EOPNOTSUPP;
-			}
+	return 0;
+}
 
-			if (!tb_tdc[IFLA_CAN_TDC_TDCO])
-				return -EOPNOTSUPP;
-		}
-	}
+static int can_ctrlmode_changelink(struct net_device *dev,
+				   struct nlattr *data[],
+				   struct netlink_ext_ack *extack)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	struct can_ctrlmode *cm;
+	u32 ctrlstatic, maskedflags, notsupp, ctrlstatic_missing;
 
-	if (data[IFLA_CAN_BITTIMING]) {
-		struct can_bittiming bt;
+	if (!data[IFLA_CAN_CTRLMODE])
+		return 0;
 
-		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
-		err = can_validate_bittiming(&bt, extack);
-		if (err)
-			return err;
-	}
+	/* Do not allow changing controller mode while running */
+	if (dev->flags & IFF_UP)
+		return -EBUSY;
 
-	if (is_can_fd) {
-		if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
-			return -EOPNOTSUPP;
+	cm = nla_data(data[IFLA_CAN_CTRLMODE]);
+	ctrlstatic = can_get_static_ctrlmode(priv);
+	maskedflags = cm->flags & cm->mask;
+	notsupp = maskedflags & ~(priv->ctrlmode_supported | ctrlstatic);
+	ctrlstatic_missing = (maskedflags & ctrlstatic) ^ ctrlstatic;
+
+	if (notsupp) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "requested control mode %s not supported",
+				   can_get_ctrlmode_str(notsupp));
+		return -EOPNOTSUPP;
 	}
 
-	if (data[IFLA_CAN_DATA_BITTIMING] || data[IFLA_CAN_TDC]) {
-		if (!is_can_fd)
-			return -EOPNOTSUPP;
+	/* do not check for static fd-non-iso if 'fd' is disabled */
+	if (!(maskedflags & CAN_CTRLMODE_FD))
+		ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
+
+	if (ctrlstatic_missing) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "missing required %s static control mode",
+				   can_get_ctrlmode_str(ctrlstatic_missing));
+		return -EOPNOTSUPP;
 	}
 
-	if (data[IFLA_CAN_DATA_BITTIMING]) {
-		struct can_bittiming bt;
+	/* If a top dependency flag is provided, reset all its dependencies */
+	if (cm->mask & CAN_CTRLMODE_FD)
+		priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
 
-		memcpy(&bt, nla_data(data[IFLA_CAN_DATA_BITTIMING]), sizeof(bt));
-		err = can_validate_bittiming(&bt, extack);
-		if (err)
-			return err;
+	/* clear bits to be modified and copy the flag values */
+	priv->ctrlmode &= ~cm->mask;
+	priv->ctrlmode |= maskedflags;
+
+	/* Wipe potential leftovers from previous CAN FD config */
+	if (!(priv->ctrlmode & CAN_CTRLMODE_FD)) {
+		memset(&priv->fd.data_bittiming, 0,
+		       sizeof(priv->fd.data_bittiming));
+		priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
+		memset(&priv->fd.tdc, 0, sizeof(priv->fd.tdc));
 	}
 
+	can_set_default_mtu(dev);
+
 	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 || !can_fd_tdc_is_enabled(priv))
+	if (!tdc_const) {
+		NL_SET_ERR_MSG(extack, "The device does not support TDC");
 		return -EOPNOTSUPP;
+	}
 
 	err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX, nla,
 			       can_tdc_policy, extack);
@@ -179,69 +308,107 @@ 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;
 }
 
-static int can_changelink(struct net_device *dev, struct nlattr *tb[],
-			  struct nlattr *data[],
-			  struct netlink_ext_ack *extack)
+static int can_dbt_changelink(struct net_device *dev, struct nlattr *data[],
+			      bool fd, struct netlink_ext_ack *extack)
 {
+	struct nlattr *data_bittiming, *data_tdc;
 	struct can_priv *priv = netdev_priv(dev);
-	bool fd_tdc_flag_provided = false;
+	struct data_bittiming_params *dbt_params;
+	struct can_bittiming dbt;
+	bool need_tdc_calc = false;
+	u32 tdc_mask;
 	int err;
 
-	/* We need synchronization with dev->stop() */
-	ASSERT_RTNL();
+	if (fd) {
+		data_bittiming = data[IFLA_CAN_DATA_BITTIMING];
+		data_tdc = data[IFLA_CAN_TDC];
+		dbt_params = &priv->fd;
+		tdc_mask = CAN_CTRLMODE_FD_TDC_MASK;
+	} else {
+		return -EOPNOTSUPP; /* Place holder for CAN XL */
+	}
 
-	if (data[IFLA_CAN_CTRLMODE]) {
-		struct can_ctrlmode *cm;
-		u32 ctrlstatic;
-		u32 maskedflags;
+	if (!data_bittiming)
+		return 0;
 
-		/* Do not allow changing controller mode while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-		cm = nla_data(data[IFLA_CAN_CTRLMODE]);
-		ctrlstatic = can_get_static_ctrlmode(priv);
-		maskedflags = cm->flags & cm->mask;
+	/* Do not allow changing bittiming while running */
+	if (dev->flags & IFF_UP)
+		return -EBUSY;
 
-		/* check whether provided bits are allowed to be passed */
-		if (maskedflags & ~(priv->ctrlmode_supported | ctrlstatic))
-			return -EOPNOTSUPP;
+	/* Calculate bittiming parameters based on data_bittiming_const
+	 * if set, otherwise pass bitrate directly via do_set_bitrate().
+	 * Bail out if neither is given.
+	 */
+	if (!dbt_params->data_bittiming_const && !dbt_params->do_set_data_bittiming &&
+	    !dbt_params->data_bitrate_const)
+		return -EOPNOTSUPP;
 
-		/* do not check for static fd-non-iso if 'fd' is disabled */
-		if (!(maskedflags & CAN_CTRLMODE_FD))
-			ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
+	memcpy(&dbt, nla_data(data_bittiming), sizeof(dbt));
+	err = can_get_bittiming(dev, &dbt, dbt_params->data_bittiming_const,
+				dbt_params->data_bitrate_const,
+				dbt_params->data_bitrate_const_cnt, extack);
+	if (err)
+		return err;
 
-		/* make sure static options are provided by configuration */
-		if ((maskedflags & ctrlstatic) != ctrlstatic)
-			return -EOPNOTSUPP;
+	if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "CAN data bitrate %u bps surpasses transceiver capabilities of %u bps",
+				   dbt.bitrate, priv->bitrate_max);
+		return -EINVAL;
+	}
 
-		/* clear bits to be modified and copy the flag values */
-		priv->ctrlmode &= ~cm->mask;
-		priv->ctrlmode |= maskedflags;
+	memset(&dbt_params->tdc, 0, sizeof(dbt_params->tdc));
+	if (data[IFLA_CAN_CTRLMODE]) {
+		struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
 
-		/* CAN_CTRLMODE_FD can only be set when driver supports FD */
-		if (priv->ctrlmode & CAN_CTRLMODE_FD) {
-			dev->mtu = CANFD_MTU;
-		} else {
-			dev->mtu = CAN_MTU;
-			memset(&priv->fd.data_bittiming, 0,
-			       sizeof(priv->fd.data_bittiming));
-			priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
-			memset(&priv->fd.tdc, 0, sizeof(priv->fd.tdc));
+		need_tdc_calc = !(cm->mask & tdc_mask);
+	}
+	if (data_tdc) {
+		/* TDC parameters are provided: use them */
+		err = can_tdc_changelink(dbt_params, data_tdc, extack);
+		if (err) {
+			priv->ctrlmode &= ~tdc_mask;
+			return err;
 		}
-
-		fd_tdc_flag_provided = cm->mask & CAN_CTRLMODE_FD_TDC_MASK;
-		/* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually
-		 * exclusive: make sure to turn the other one off
+	} else if (need_tdc_calc) {
+		/* Neither of TDC parameters nor TDC flags are provided:
+		 * do calculation
 		 */
-		if (fd_tdc_flag_provided)
-			priv->ctrlmode &= cm->flags | ~CAN_CTRLMODE_FD_TDC_MASK;
+		can_calc_tdco(&dbt_params->tdc, dbt_params->tdc_const, &dbt,
+			      tdc_mask, &priv->ctrlmode, priv->ctrlmode_supported);
+	} /* else: both CAN_CTRLMODE_TDC_{AUTO,MANUAL} are explicitly
+	   * turned off. TDC is disabled: do nothing
+	   */
+
+	memcpy(&dbt_params->data_bittiming, &dbt, sizeof(dbt));
+
+	if (dbt_params->do_set_data_bittiming) {
+		/* Finally, set the bit-timing registers */
+		err = dbt_params->do_set_data_bittiming(dev);
+		if (err)
+			return err;
 	}
 
+	return 0;
+}
+
+static int can_changelink(struct net_device *dev, struct nlattr *tb[],
+			  struct nlattr *data[],
+			  struct netlink_ext_ack *extack)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	int err;
+
+	/* We need synchronization with dev->stop() */
+	ASSERT_RTNL();
+
+	can_ctrlmode_changelink(dev, data, extack);
+
 	if (data[IFLA_CAN_BITTIMING]) {
 		struct can_bittiming bt;
 
@@ -312,75 +479,21 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 			return err;
 	}
 
-	if (data[IFLA_CAN_DATA_BITTIMING]) {
-		struct can_bittiming dbt;
-
-		/* Do not allow changing bittiming while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-
-		/* Calculate bittiming parameters based on
-		 * data_bittiming_const if set, otherwise pass bitrate
-		 * directly via do_set_bitrate(). Bail out if neither
-		 * is given.
-		 */
-		if (!priv->fd.data_bittiming_const && !priv->fd.do_set_data_bittiming &&
-		    !priv->fd.data_bitrate_const)
-			return -EOPNOTSUPP;
-
-		memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
-		       sizeof(dbt));
-		err = can_get_bittiming(dev, &dbt,
-					priv->fd.data_bittiming_const,
-					priv->fd.data_bitrate_const,
-					priv->fd.data_bitrate_const_cnt,
-					extack);
-		if (err)
-			return err;
-
-		if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
-			NL_SET_ERR_MSG_FMT(extack,
-					   "CANFD data bitrate %u bps surpasses transceiver capabilities of %u bps",
-					   dbt.bitrate, priv->bitrate_max);
-			return -EINVAL;
-		}
-
-		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);
-			if (err) {
-				priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
-				return err;
-			}
-		} else if (!fd_tdc_flag_provided) {
-			/* Neither of TDC parameters nor TDC flags are
-			 * provided: do calculation
-			 */
-			can_calc_tdco(&priv->fd.tdc, priv->fd.tdc_const, &dbt,
-				      &priv->ctrlmode, priv->ctrlmode_supported);
-		} /* else: both CAN_CTRLMODE_TDC_{AUTO,MANUAL} are explicitly
-		   * turned off. TDC is disabled: do nothing
-		   */
-
-		memcpy(&priv->fd.data_bittiming, &dbt, sizeof(dbt));
-
-		if (priv->fd.do_set_data_bittiming) {
-			/* Finally, set the bit-timing registers */
-			err = priv->fd.do_set_data_bittiming(dev);
-			if (err)
-				return err;
-		}
-	}
+	/* CAN FD */
+	err = can_dbt_changelink(dev, data, true, extack);
+	if (err)
+		return err;
 
 	if (data[IFLA_CAN_TERMINATION]) {
 		const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
 		const unsigned int num_term = priv->termination_const_cnt;
 		unsigned int i;
 
-		if (!priv->do_set_termination)
+		if (!priv->do_set_termination) {
+			NL_SET_ERR_MSG(extack,
+				       "Termination is not configurable on this device");
 			return -EOPNOTSUPP;
+		}
 
 		/* check whether given value is supported by the interface */
 		for (i = 0; i < num_term; i++) {
@@ -401,38 +514,55 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 	return 0;
 }
 
-static size_t can_tdc_get_size(const struct net_device *dev)
+static size_t can_tdc_get_size(struct data_bittiming_params *dbt_params,
+			       u32 tdc_flags)
 {
-	struct can_priv *priv = netdev_priv(dev);
+	bool tdc_manual = tdc_flags & CAN_CTRLMODE_TDC_MANUAL_MASK;
 	size_t size;
 
-	if (!priv->fd.tdc_const)
+	if (!dbt_params->tdc_const)
 		return 0;
 
 	size = nla_total_size(0);			/* nest IFLA_CAN_TDC */
-	if (priv->ctrlmode_supported & CAN_CTRLMODE_TDC_MANUAL) {
+	if (tdc_manual) {
 		size += nla_total_size(sizeof(u32));	/* IFLA_CAN_TDCV_MIN */
 		size += nla_total_size(sizeof(u32));	/* IFLA_CAN_TDCV_MAX */
 	}
 	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_TDCO_MIN */
 	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_TDCO_MAX */
-	if (priv->fd.tdc_const->tdcf_max) {
+	if (dbt_params->tdc_const->tdcf_max) {
 		size += nla_total_size(sizeof(u32));	/* IFLA_CAN_TDCF_MIN */
 		size += nla_total_size(sizeof(u32));	/* IFLA_CAN_TDCF_MAX */
 	}
 
-	if (can_fd_tdc_is_enabled(priv)) {
-		if (priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL ||
-		    priv->fd.do_get_auto_tdcv)
+	if (tdc_flags) {
+		if (tdc_manual || dbt_params->do_get_auto_tdcv)
 			size += nla_total_size(sizeof(u32));	/* IFLA_CAN_TDCV */
 		size += nla_total_size(sizeof(u32));		/* IFLA_CAN_TDCO */
-		if (priv->fd.tdc_const->tdcf_max)
+		if (dbt_params->tdc_const->tdcf_max)
 			size += nla_total_size(sizeof(u32));	/* IFLA_CAN_TDCF */
 	}
 
 	return size;
 }
 
+static size_t can_data_bittiming_get_size(struct data_bittiming_params *dbt_params,
+					  u32 tdc_flags)
+{
+	size_t size = 0;
+
+	if (dbt_params->data_bittiming.bitrate)		/* IFLA_CAN_DATA_BITTIMING */
+		size += nla_total_size(sizeof(dbt_params->data_bittiming));
+	if (dbt_params->data_bittiming_const)		/* IFLA_CAN_DATA_BITTIMING_CONST */
+		size += nla_total_size(sizeof(*dbt_params->data_bittiming_const));
+	if (dbt_params->data_bitrate_const)		/* IFLA_CAN_DATA_BITRATE_CONST */
+		size += nla_total_size(sizeof(*dbt_params->data_bitrate_const) *
+				       dbt_params->data_bitrate_const_cnt);
+	size += can_tdc_get_size(dbt_params, tdc_flags);/* IFLA_CAN_TDC */
+
+	return size;
+}
+
 static size_t can_ctrlmode_ext_get_size(void)
 {
 	return nla_total_size(0) +		/* nest IFLA_CAN_CTRLMODE_EXT */
@@ -454,10 +584,6 @@ static size_t can_get_size(const struct net_device *dev)
 	size += nla_total_size(sizeof(u32));			/* IFLA_CAN_RESTART_MS */
 	if (priv->do_get_berr_counter)				/* IFLA_CAN_BERR_COUNTER */
 		size += nla_total_size(sizeof(struct can_berr_counter));
-	if (priv->fd.data_bittiming.bitrate)			/* IFLA_CAN_DATA_BITTIMING */
-		size += nla_total_size(sizeof(struct can_bittiming));
-	if (priv->fd.data_bittiming_const)			/* IFLA_CAN_DATA_BITTIMING_CONST */
-		size += nla_total_size(sizeof(struct can_bittiming_const));
 	if (priv->termination_const) {
 		size += nla_total_size(sizeof(priv->termination));		/* IFLA_CAN_TERMINATION */
 		size += nla_total_size(sizeof(*priv->termination_const) *	/* IFLA_CAN_TERMINATION_CONST */
@@ -466,31 +592,69 @@ static size_t can_get_size(const struct net_device *dev)
 	if (priv->bitrate_const)				/* IFLA_CAN_BITRATE_CONST */
 		size += nla_total_size(sizeof(*priv->bitrate_const) *
 				       priv->bitrate_const_cnt);
-	if (priv->fd.data_bitrate_const)			/* IFLA_CAN_DATA_BITRATE_CONST */
-		size += nla_total_size(sizeof(*priv->fd.data_bitrate_const) *
-				       priv->fd.data_bitrate_const_cnt);
 	size += sizeof(priv->bitrate_max);			/* IFLA_CAN_BITRATE_MAX */
-	size += can_tdc_get_size(dev);				/* IFLA_CAN_TDC */
 	size += can_ctrlmode_ext_get_size();			/* IFLA_CAN_CTRLMODE_EXT */
 
+	size += can_data_bittiming_get_size(&priv->fd,
+					    priv->ctrlmode & CAN_CTRLMODE_FD_TDC_MASK);
+
 	return size;
 }
 
-static int can_tdc_fill_info(struct sk_buff *skb, const struct net_device *dev)
+static int can_bittiming_fill_info(struct sk_buff *skb, int ifla_can_bittiming,
+				   struct can_bittiming *bittiming)
+{
+	return bittiming->bitrate != CAN_BITRATE_UNSET &&
+		bittiming->bitrate != CAN_BITRATE_UNKNOWN &&
+		nla_put(skb, ifla_can_bittiming, sizeof(*bittiming), bittiming);
+}
+
+static int can_bittiming_const_fill_info(struct sk_buff *skb,
+					 int ifla_can_bittiming_const,
+					 const struct can_bittiming_const *bittiming_const)
+{
+	return bittiming_const &&
+		nla_put(skb, ifla_can_bittiming_const,
+			sizeof(*bittiming_const), bittiming_const);
+}
+
+static int can_bitrate_const_fill_info(struct sk_buff *skb,
+				       int ifla_can_bitrate_const,
+				       const u32 *bitrate_const, unsigned int cnt)
+{
+	return bitrate_const &&
+		nla_put(skb, ifla_can_bitrate_const,
+			sizeof(*bitrate_const) * cnt, bitrate_const);
+}
+
+static int can_tdc_fill_info(struct sk_buff *skb, const struct net_device *dev,
+			     int ifla_can_tdc)
 {
-	struct nlattr *nest;
 	struct can_priv *priv = netdev_priv(dev);
-	struct can_tdc *tdc = &priv->fd.tdc;
-	const struct can_tdc_const *tdc_const = priv->fd.tdc_const;
+	struct data_bittiming_params *dbt_params;
+	const struct can_tdc_const *tdc_const;
+	struct can_tdc *tdc;
+	struct nlattr *nest;
+	bool tdc_is_enabled, tdc_manual;
+
+	if (ifla_can_tdc == IFLA_CAN_TDC) {
+		dbt_params = &priv->fd;
+		tdc_is_enabled = can_fd_tdc_is_enabled(priv);
+		tdc_manual = priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL;
+	} else {
+		return -EOPNOTSUPP; /* Place holder for CAN XL */
+	}
+	tdc_const = dbt_params->tdc_const;
+	tdc = &dbt_params->tdc;
 
 	if (!tdc_const)
 		return 0;
 
-	nest = nla_nest_start(skb, IFLA_CAN_TDC);
+	nest = nla_nest_start(skb, ifla_can_tdc);
 	if (!nest)
 		return -EMSGSIZE;
 
-	if (priv->ctrlmode_supported & CAN_CTRLMODE_TDC_MANUAL &&
+	if (tdc_manual &&
 	    (nla_put_u32(skb, IFLA_CAN_TDC_TDCV_MIN, tdc_const->tdcv_min) ||
 	     nla_put_u32(skb, IFLA_CAN_TDC_TDCV_MAX, tdc_const->tdcv_max)))
 		goto err_cancel;
@@ -502,15 +666,15 @@ static int can_tdc_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	     nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MAX, tdc_const->tdcf_max)))
 		goto err_cancel;
 
-	if (can_fd_tdc_is_enabled(priv)) {
+	if (tdc_is_enabled) {
 		u32 tdcv;
 		int err = -EINVAL;
 
-		if (priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL) {
+		if (tdc_manual) {
 			tdcv = tdc->tdcv;
 			err = 0;
-		} else if (priv->fd.do_get_auto_tdcv) {
-			err = priv->fd.do_get_auto_tdcv(dev, &tdcv);
+		} else if (dbt_params->do_get_auto_tdcv) {
+			err = dbt_params->do_get_auto_tdcv(dev, &tdcv);
 		}
 		if (!err && nla_put_u32(skb, IFLA_CAN_TDC_TDCV, tdcv))
 			goto err_cancel;
@@ -558,14 +722,11 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	if (priv->do_get_state)
 		priv->do_get_state(dev, &state);
 
-	if ((priv->bittiming.bitrate != CAN_BITRATE_UNSET &&
-	     priv->bittiming.bitrate != CAN_BITRATE_UNKNOWN &&
-	     nla_put(skb, IFLA_CAN_BITTIMING,
-		     sizeof(priv->bittiming), &priv->bittiming)) ||
+	if (can_bittiming_fill_info(skb, IFLA_CAN_BITTIMING,
+				    &priv->bittiming) ||
 
-	    (priv->bittiming_const &&
-	     nla_put(skb, IFLA_CAN_BITTIMING_CONST,
-		     sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
+	    can_bittiming_const_fill_info(skb, IFLA_CAN_BITTIMING_CONST,
+					  priv->bittiming_const) ||
 
 	    nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
 	    nla_put_u32(skb, IFLA_CAN_STATE, state) ||
@@ -576,14 +737,11 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	     !priv->do_get_berr_counter(dev, &bec) &&
 	     nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
 
-	    (priv->fd.data_bittiming.bitrate &&
-	     nla_put(skb, IFLA_CAN_DATA_BITTIMING,
-		     sizeof(priv->fd.data_bittiming), &priv->fd.data_bittiming)) ||
+	    can_bittiming_fill_info(skb, IFLA_CAN_DATA_BITTIMING,
+				    &priv->fd.data_bittiming) ||
 
-	    (priv->fd.data_bittiming_const &&
-	     nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
-		     sizeof(*priv->fd.data_bittiming_const),
-		     priv->fd.data_bittiming_const)) ||
+	    can_bittiming_const_fill_info(skb, IFLA_CAN_DATA_BITTIMING_CONST,
+					  priv->fd.data_bittiming_const) ||
 
 	    (priv->termination_const &&
 	     (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
@@ -592,23 +750,19 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 		      priv->termination_const_cnt,
 		      priv->termination_const))) ||
 
-	    (priv->bitrate_const &&
-	     nla_put(skb, IFLA_CAN_BITRATE_CONST,
-		     sizeof(*priv->bitrate_const) *
-		     priv->bitrate_const_cnt,
-		     priv->bitrate_const)) ||
+	    can_bitrate_const_fill_info(skb, IFLA_CAN_BITRATE_CONST,
+					priv->bitrate_const,
+					priv->bitrate_const_cnt) ||
 
-	    (priv->fd.data_bitrate_const &&
-	     nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
-		     sizeof(*priv->fd.data_bitrate_const) *
-		     priv->fd.data_bitrate_const_cnt,
-		     priv->fd.data_bitrate_const)) ||
+	    can_bitrate_const_fill_info(skb, IFLA_CAN_DATA_BITRATE_CONST,
+					priv->fd.data_bitrate_const,
+					priv->fd.data_bitrate_const_cnt) ||
 
 	    (nla_put(skb, IFLA_CAN_BITRATE_MAX,
 		     sizeof(priv->bitrate_max),
 		     &priv->bitrate_max)) ||
 
-	    can_tdc_fill_info(skb, dev) ||
+	    can_tdc_fill_info(skb, dev, IFLA_CAN_TDC) ||
 
 	    can_ctrlmode_ext_fill_info(skb, priv)
 	    )