Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

8 files changed, 3209 insertions, 0 deletions

diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile
new file mode 100644
index 000000000..633687d6b
--- /dev/null
+++ b/drivers/net/can/dev/Makefile
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_CAN_DEV) += can-dev.o
+
+can-dev-y += skb.o
+
+can-dev-$(CONFIG_CAN_CALC_BITTIMING) += calc_bittiming.o
+can-dev-$(CONFIG_CAN_NETLINK) += bittiming.o
+can-dev-$(CONFIG_CAN_NETLINK) += dev.o
+can-dev-$(CONFIG_CAN_NETLINK) += length.o
+can-dev-$(CONFIG_CAN_NETLINK) += netlink.o
+can-dev-$(CONFIG_CAN_RX_OFFLOAD) += rx-offload.o
diff --git a/drivers/net/can/dev/bittiming.c b/drivers/net/can/dev/bittiming.c
new file mode 100644
index 000000000..8f8241823
--- /dev/null
+++ b/drivers/net/can/dev/bittiming.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
+ * Copyright (C) 2006 Andrey Volkov, Varma Electronics
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ * Copyright (c) 2025 Vincent Mailhol <mailhol@kernel.org>
+ */
+
+#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 sane default of phase_seg2 / 2 */
+	bt->sjw = max(1U, min(bt->phase_seg1, bt->phase_seg2 / 2));
+}
+
+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) {
+		NL_SET_ERR_MSG_FMT(extack, "sjw: %u greater than max sjw: %u",
+				   bt->sjw, btc->sjw_max);
+		return -EINVAL;
+	}
+
+	if (bt->sjw > bt->phase_seg1) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "sjw: %u greater than phase-seg1: %u",
+				   bt->sjw, bt->phase_seg1);
+		return -EINVAL;
+	}
+
+	if (bt->sjw > bt->phase_seg2) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "sjw: %u greater than phase-seg2: %u",
+				   bt->sjw, bt->phase_seg2);
+		return -EINVAL;
+	}
+
+	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
+ * file linux/can/netlink.h.
+ */
+static int can_fixup_bittiming(const struct net_device *dev, struct can_bittiming *bt,
+			       const struct can_bittiming_const *btc,
+			       struct netlink_ext_ack *extack)
+{
+	const unsigned int tseg1 = bt->prop_seg + bt->phase_seg1;
+	const struct can_priv *priv = netdev_priv(dev);
+	u64 brp64;
+	int err;
+
+	if (tseg1 < btc->tseg1_min) {
+		NL_SET_ERR_MSG_FMT(extack, "prop-seg + phase-seg1: %u less than tseg1-min: %u",
+				   tseg1, btc->tseg1_min);
+		return -EINVAL;
+	}
+	if (tseg1 > btc->tseg1_max) {
+		NL_SET_ERR_MSG_FMT(extack, "prop-seg + phase-seg1: %u greater than tseg1-max: %u",
+				   tseg1, btc->tseg1_max);
+		return -EINVAL;
+	}
+	if (bt->phase_seg2 < btc->tseg2_min) {
+		NL_SET_ERR_MSG_FMT(extack, "phase-seg2: %u less than tseg2-min: %u",
+				   bt->phase_seg2, btc->tseg2_min);
+		return -EINVAL;
+	}
+	if (bt->phase_seg2 > btc->tseg2_max) {
+		NL_SET_ERR_MSG_FMT(extack, "phase-seg2: %u greater than tseg2-max: %u",
+				   bt->phase_seg2, btc->tseg2_max);
+		return -EINVAL;
+	}
+
+	can_sjw_set_default(bt);
+
+	err = can_sjw_check(dev, bt, btc, extack);
+	if (err)
+		return err;
+
+	brp64 = (u64)priv->clock.freq * (u64)bt->tq;
+	if (btc->brp_inc > 1)
+		do_div(brp64, btc->brp_inc);
+	brp64 += 500000000UL - 1;
+	do_div(brp64, 1000000000UL); /* the practicable BRP */
+	if (btc->brp_inc > 1)
+		brp64 *= btc->brp_inc;
+	bt->brp = (u32)brp64;
+
+	if (bt->brp < btc->brp_min) {
+		NL_SET_ERR_MSG_FMT(extack, "resulting brp: %u less than brp-min: %u",
+				   bt->brp, btc->brp_min);
+		return -EINVAL;
+	}
+	if (bt->brp > btc->brp_max) {
+		NL_SET_ERR_MSG_FMT(extack, "resulting brp: %u greater than brp-max: %u",
+				   bt->brp, btc->brp_max);
+		return -EINVAL;
+	}
+
+	bt->bitrate = priv->clock.freq / (bt->brp * can_bit_time(bt));
+	bt->sample_point = ((CAN_SYNC_SEG + tseg1) * 1000) / can_bit_time(bt);
+	bt->tq = DIV_U64_ROUND_CLOSEST(mul_u32_u32(bt->brp, NSEC_PER_SEC),
+				       priv->clock.freq);
+
+	return 0;
+}
+
+/* Checks the validity of predefined bitrate settings */
+static int
+can_validate_bitrate(const struct net_device *dev, const struct can_bittiming *bt,
+		     const u32 *bitrate_const,
+		     const unsigned int bitrate_const_cnt,
+		     struct netlink_ext_ack *extack)
+{
+	unsigned int i;
+
+	for (i = 0; i < bitrate_const_cnt; i++) {
+		if (bt->bitrate == bitrate_const[i])
+			return 0;
+	}
+
+	NL_SET_ERR_MSG_FMT(extack, "bitrate %u bps not supported",
+			   bt->brp);
+
+	return -EINVAL;
+}
+
+int can_get_bittiming(const struct net_device *dev, struct can_bittiming *bt,
+		      const struct can_bittiming_const *btc,
+		      const u32 *bitrate_const,
+		      const unsigned int bitrate_const_cnt,
+		      struct netlink_ext_ack *extack)
+{
+	/* Depending on the given can_bittiming parameter structure the CAN
+	 * timing parameters are calculated based on the provided bitrate OR
+	 * alternatively the CAN timing parameters (tq, prop_seg, etc.) are
+	 * provided directly which are then checked and fixed up.
+	 */
+	if (!bt->tq && bt->bitrate && btc)
+		return can_calc_bittiming(dev, bt, btc, extack);
+	if (bt->tq && !bt->bitrate && btc)
+		return can_fixup_bittiming(dev, bt, btc, extack);
+	if (!bt->tq && bt->bitrate && bitrate_const)
+		return can_validate_bitrate(dev, bt, bitrate_const,
+					    bitrate_const_cnt, extack);
+
+	return -EINVAL;
+}
+
+int can_validate_pwm_bittiming(const struct net_device *dev,
+			       const struct can_pwm *pwm,
+			       struct netlink_ext_ack *extack)
+{
+	const struct can_priv *priv = netdev_priv(dev);
+	u32 xl_bit_time_tqmin = can_bit_time_tqmin(&priv->xl.data_bittiming);
+	u32 nom_bit_time_tqmin = can_bit_time_tqmin(&priv->bittiming);
+	u32 pwms_ns = can_tqmin_to_ns(pwm->pwms, priv->clock.freq);
+	u32 pwml_ns = can_tqmin_to_ns(pwm->pwml, priv->clock.freq);
+
+	if (pwms_ns + pwml_ns > CAN_PWM_NS_MAX) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "The PWM symbol duration: %u ns may not exceed %u ns",
+				   pwms_ns + pwml_ns, CAN_PWM_NS_MAX);
+		return -EINVAL;
+	}
+
+	if (pwms_ns < CAN_PWM_DECODE_NS) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "PWMS: %u ns shall be at least %u ns",
+				   pwms_ns, CAN_PWM_DECODE_NS);
+		return -EINVAL;
+	}
+
+	if (pwm->pwms >= pwm->pwml) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "PWMS: %u tqmin shall be smaller than PWML: %u tqmin",
+				   pwm->pwms, pwm->pwml);
+		return -EINVAL;
+	}
+
+	if (pwml_ns - pwms_ns < 2 * CAN_PWM_DECODE_NS) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "At least %u ns shall separate PWMS: %u ns from PMWL: %u ns",
+				   2 * CAN_PWM_DECODE_NS, pwms_ns, pwml_ns);
+		return -EINVAL;
+	}
+
+	if (xl_bit_time_tqmin % (pwm->pwms + pwm->pwml) != 0) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "PWM duration: %u tqmin does not divide XL's bit time: %u tqmin",
+				   pwm->pwms + pwm->pwml, xl_bit_time_tqmin);
+		return -EINVAL;
+	}
+
+	if (pwm->pwmo >= pwm->pwms + pwm->pwml) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "PWMO: %u tqmin can not be greater than PWMS + PWML: %u tqmin",
+				   pwm->pwmo, pwm->pwms + pwm->pwml);
+		return -EINVAL;
+	}
+
+	if (nom_bit_time_tqmin % (pwm->pwms + pwm->pwml) != pwm->pwmo) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "Can not assemble nominal bit time: %u tqmin out of PWMS + PMWL and PWMO",
+				   nom_bit_time_tqmin);
+		return -EINVAL;
+	}
+
+	return 0;
+}
diff --git a/drivers/net/can/dev/calc_bittiming.c b/drivers/net/can/dev/calc_bittiming.c
new file mode 100644
index 000000000..42498e9d3
--- /dev/null
+++ b/drivers/net/can/dev/calc_bittiming.c
@@ -0,0 +1,262 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
+ * Copyright (C) 2006 Andrey Volkov, Varma Electronics
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ * Copyright (C) 2021-2025 Vincent Mailhol <mailhol@kernel.org>
+ */
+
+#include <linux/units.h>
+#include <linux/can/dev.h>
+
+#define CAN_CALC_MAX_ERROR 500 /* max error 5% */
+
+/* CiA recommended sample points for Non Return to Zero encoding. */
+static int can_calc_sample_point_nrz(const struct can_bittiming *bt)
+{
+	if (bt->bitrate > 800 * KILO /* BPS */)
+		return 750;
+
+	if (bt->bitrate > 500 * KILO /* BPS */)
+		return 800;
+
+	return 875;
+}
+
+/* Sample points for Pulse-Width Modulation encoding. */
+static int can_calc_sample_point_pwm(const struct can_bittiming *bt)
+{
+	if (bt->bitrate > 15 * MEGA /* BPS */)
+		return 625;
+
+	if (bt->bitrate > 9 * MEGA /* BPS */)
+		return 600;
+
+	if (bt->bitrate > 4 * MEGA /* BPS */)
+		return 560;
+
+	return 520;
+}
+
+/* Bit-timing calculation derived from:
+ *
+ * Code based on LinCAN sources and H8S2638 project
+ * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
+ * Copyright 2005      Stanislav Marek
+ * email: pisa@cmp.felk.cvut.cz
+ *
+ * Calculates proper bit-timing parameters for a specified bit-rate
+ * and sample-point, which can then be used to set the bit-timing
+ * registers of the CAN controller. You can find more information
+ * in the header file linux/can/netlink.h.
+ */
+static int
+can_update_sample_point(const struct can_bittiming_const *btc,
+			const unsigned int sample_point_reference, const unsigned int tseg,
+			unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
+			unsigned int *sample_point_error_ptr)
+{
+	unsigned int sample_point_error, best_sample_point_error = UINT_MAX;
+	unsigned int sample_point, best_sample_point = 0;
+	unsigned int tseg1, tseg2;
+	int i;
+
+	for (i = 0; i <= 1; i++) {
+		tseg2 = tseg + CAN_SYNC_SEG -
+			(sample_point_reference * (tseg + CAN_SYNC_SEG)) /
+			1000 - i;
+		tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
+		tseg1 = tseg - tseg2;
+		if (tseg1 > btc->tseg1_max) {
+			tseg1 = btc->tseg1_max;
+			tseg2 = tseg - tseg1;
+		}
+
+		sample_point = 1000 * (tseg + CAN_SYNC_SEG - tseg2) /
+			(tseg + CAN_SYNC_SEG);
+		sample_point_error = abs(sample_point_reference - sample_point);
+
+		if (sample_point <= sample_point_reference &&
+		    sample_point_error < best_sample_point_error) {
+			best_sample_point = sample_point;
+			best_sample_point_error = sample_point_error;
+			*tseg1_ptr = tseg1;
+			*tseg2_ptr = tseg2;
+		}
+	}
+
+	if (sample_point_error_ptr)
+		*sample_point_error_ptr = best_sample_point_error;
+
+	return best_sample_point;
+}
+
+int can_calc_bittiming(const struct net_device *dev, struct can_bittiming *bt,
+		       const struct can_bittiming_const *btc, struct netlink_ext_ack *extack)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	unsigned int bitrate;			/* current bitrate */
+	unsigned int bitrate_error;		/* diff between calculated and reference value */
+	unsigned int best_bitrate_error = UINT_MAX;
+	unsigned int sample_point_error;	/* diff between calculated and reference value */
+	unsigned int best_sample_point_error = UINT_MAX;
+	unsigned int sample_point_reference;	/* reference sample point */
+	unsigned int best_tseg = 0;		/* current best value for tseg */
+	unsigned int best_brp = 0;		/* current best value for brp */
+	unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
+	u64 v64;
+	int err;
+
+	if (bt->sample_point)
+		sample_point_reference = bt->sample_point;
+	else if (btc == priv->xl.data_bittiming_const &&
+		 (priv->ctrlmode & CAN_CTRLMODE_XL_TMS))
+		sample_point_reference = can_calc_sample_point_pwm(bt);
+	else
+		sample_point_reference = can_calc_sample_point_nrz(bt);
+
+	/* tseg even = round down, odd = round up */
+	for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
+	     tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
+		tsegall = CAN_SYNC_SEG + tseg / 2;
+
+		/* Compute all possible tseg choices (tseg=tseg1+tseg2) */
+		brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
+
+		/* choose brp step which is possible in system */
+		brp = (brp / btc->brp_inc) * btc->brp_inc;
+		if (brp < btc->brp_min || brp > btc->brp_max)
+			continue;
+
+		bitrate = priv->clock.freq / (brp * tsegall);
+		bitrate_error = abs(bt->bitrate - bitrate);
+
+		/* tseg brp biterror */
+		if (bitrate_error > best_bitrate_error)
+			continue;
+
+		/* reset sample point error if we have a better bitrate */
+		if (bitrate_error < best_bitrate_error)
+			best_sample_point_error = UINT_MAX;
+
+		can_update_sample_point(btc, sample_point_reference, tseg / 2,
+					&tseg1, &tseg2, &sample_point_error);
+		if (sample_point_error >= best_sample_point_error)
+			continue;
+
+		best_sample_point_error = sample_point_error;
+		best_bitrate_error = bitrate_error;
+		best_tseg = tseg / 2;
+		best_brp = brp;
+
+		if (bitrate_error == 0 && sample_point_error == 0)
+			break;
+	}
+
+	if (best_bitrate_error) {
+		/* Error in one-hundredth of a percent */
+		v64 = (u64)best_bitrate_error * 10000;
+		do_div(v64, bt->bitrate);
+		bitrate_error = (u32)v64;
+		/* print at least 0.01% if the error is smaller */
+		bitrate_error = max(bitrate_error, 1U);
+		if (bitrate_error > CAN_CALC_MAX_ERROR) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "bitrate error: %u.%02u%% too high",
+					   bitrate_error / 100,
+					   bitrate_error % 100);
+			return -EINVAL;
+		}
+		NL_SET_ERR_MSG_FMT(extack,
+				   "bitrate error: %u.%02u%%",
+				   bitrate_error / 100, bitrate_error % 100);
+	}
+
+	/* real sample point */
+	bt->sample_point = can_update_sample_point(btc, sample_point_reference,
+						   best_tseg, &tseg1, &tseg2,
+						   NULL);
+
+	v64 = (u64)best_brp * 1000 * 1000 * 1000;
+	do_div(v64, priv->clock.freq);
+	bt->tq = (u32)v64;
+	bt->prop_seg = tseg1 / 2;
+	bt->phase_seg1 = tseg1 - bt->prop_seg;
+	bt->phase_seg2 = tseg2;
+
+	can_sjw_set_default(bt);
+
+	err = can_sjw_check(dev, bt, btc, extack);
+	if (err)
+		return err;
+
+	bt->brp = best_brp;
+
+	/* real bitrate */
+	bt->bitrate = priv->clock.freq /
+		(bt->brp * can_bit_time(bt));
+
+	return 0;
+}
+
+void can_calc_tdco(struct can_tdc *tdc, const struct can_tdc_const *tdc_const,
+		   const struct can_bittiming *dbt,
+		   u32 tdc_mask, u32 *ctrlmode, u32 ctrlmode_supported)
+
+{
+	u32 tdc_auto = tdc_mask & CAN_CTRLMODE_TDC_AUTO_MASK;
+
+	if (!tdc_const || !(ctrlmode_supported & tdc_auto))
+		return;
+
+	*ctrlmode &= ~tdc_mask;
+
+	/* As specified in ISO 11898-1 section 11.3.3 "Transmitter
+	 * delay compensation" (TDC) is only applicable if data BRP is
+	 * one or two.
+	 */
+	if (dbt->brp == 1 || dbt->brp == 2) {
+		/* Sample point in clock periods */
+		u32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg +
+					  dbt->phase_seg1) * dbt->brp;
+
+		if (sample_point_in_tc < tdc_const->tdco_min)
+			return;
+		tdc->tdco = min(sample_point_in_tc, tdc_const->tdco_max);
+		*ctrlmode |= tdc_auto;
+	}
+}
+
+int can_calc_pwm(struct net_device *dev, struct netlink_ext_ack *extack)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	const struct can_pwm_const *pwm_const = priv->xl.pwm_const;
+	struct can_pwm *pwm = &priv->xl.pwm;
+	u32 xl_tqmin = can_bit_time_tqmin(&priv->xl.data_bittiming);
+	u32 xl_ns = can_tqmin_to_ns(xl_tqmin, priv->clock.freq);
+	u32 nom_tqmin = can_bit_time_tqmin(&priv->bittiming);
+	int pwm_per_bit_max = xl_tqmin / (pwm_const->pwms_min + pwm_const->pwml_min);
+	int pwm_per_bit;
+	u32 pwm_tqmin;
+
+	/* For 5 MB/s databitrate or greater, xl_ns < CAN_PWM_NS_MAX
+	 * giving us a pwm_per_bit of 1 and the loop immediately breaks
+	 */
+	for (pwm_per_bit = DIV_ROUND_UP(xl_ns, CAN_PWM_NS_MAX);
+	     pwm_per_bit <= pwm_per_bit_max; pwm_per_bit++)
+		if (xl_tqmin % pwm_per_bit == 0)
+			break;
+
+	if (pwm_per_bit > pwm_per_bit_max) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "Can not divide the XL data phase's bit time: %u tqmin into multiple PWM symbols",
+				   xl_tqmin);
+		return -EINVAL;
+	}
+
+	pwm_tqmin = xl_tqmin / pwm_per_bit;
+	pwm->pwms = DIV_ROUND_UP_POW2(pwm_tqmin, 4);
+	pwm->pwml = pwm_tqmin - pwm->pwms;
+	pwm->pwmo = nom_tqmin % pwm_tqmin;
+
+	return 0;
+}
diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c
new file mode 100644
index 000000000..769745e22
--- /dev/null
+++ b/drivers/net/can/dev/dev.c
@@ -0,0 +1,689 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
+ * Copyright (C) 2006 Andrey Volkov, Varma Electronics
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ */
+
+#include <linux/can.h>
+#include <linux/can/can-ml.h>
+#include <linux/can/dev.h>
+#include <linux/can/skb.h>
+#include <linux/gpio/consumer.h>
+#include <linux/if_arp.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+static void can_update_state_error_stats(struct net_device *dev,
+					 enum can_state new_state)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (new_state <= priv->state)
+		return;
+
+	switch (new_state) {
+	case CAN_STATE_ERROR_WARNING:
+		priv->can_stats.error_warning++;
+		break;
+	case CAN_STATE_ERROR_PASSIVE:
+		priv->can_stats.error_passive++;
+		break;
+	case CAN_STATE_BUS_OFF:
+		priv->can_stats.bus_off++;
+		break;
+	default:
+		break;
+	}
+}
+
+static int can_tx_state_to_frame(struct net_device *dev, enum can_state state)
+{
+	switch (state) {
+	case CAN_STATE_ERROR_ACTIVE:
+		return CAN_ERR_CRTL_ACTIVE;
+	case CAN_STATE_ERROR_WARNING:
+		return CAN_ERR_CRTL_TX_WARNING;
+	case CAN_STATE_ERROR_PASSIVE:
+		return CAN_ERR_CRTL_TX_PASSIVE;
+	default:
+		return 0;
+	}
+}
+
+static int can_rx_state_to_frame(struct net_device *dev, enum can_state state)
+{
+	switch (state) {
+	case CAN_STATE_ERROR_ACTIVE:
+		return CAN_ERR_CRTL_ACTIVE;
+	case CAN_STATE_ERROR_WARNING:
+		return CAN_ERR_CRTL_RX_WARNING;
+	case CAN_STATE_ERROR_PASSIVE:
+		return CAN_ERR_CRTL_RX_PASSIVE;
+	default:
+		return 0;
+	}
+}
+
+const char *can_get_state_str(const enum can_state state)
+{
+	switch (state) {
+	case CAN_STATE_ERROR_ACTIVE:
+		return "Error Active";
+	case CAN_STATE_ERROR_WARNING:
+		return "Error Warning";
+	case CAN_STATE_ERROR_PASSIVE:
+		return "Error Passive";
+	case CAN_STATE_BUS_OFF:
+		return "Bus Off";
+	case CAN_STATE_STOPPED:
+		return "Stopped";
+	case CAN_STATE_SLEEPING:
+		return "Sleeping";
+	default:
+		return "<unknown>";
+	}
+}
+EXPORT_SYMBOL_GPL(can_get_state_str);
+
+const char *can_get_ctrlmode_str(u32 ctrlmode)
+{
+	switch (ctrlmode & ~(ctrlmode - 1)) {
+	case 0:
+		return "(none)";
+	case CAN_CTRLMODE_LOOPBACK:
+		return "LOOPBACK";
+	case CAN_CTRLMODE_LISTENONLY:
+		return "LISTEN-ONLY";
+	case CAN_CTRLMODE_3_SAMPLES:
+		return "TRIPLE-SAMPLING";
+	case CAN_CTRLMODE_ONE_SHOT:
+		return "ONE-SHOT";
+	case CAN_CTRLMODE_BERR_REPORTING:
+		return "BERR-REPORTING";
+	case CAN_CTRLMODE_FD:
+		return "FD";
+	case CAN_CTRLMODE_PRESUME_ACK:
+		return "PRESUME-ACK";
+	case CAN_CTRLMODE_FD_NON_ISO:
+		return "FD-NON-ISO";
+	case CAN_CTRLMODE_CC_LEN8_DLC:
+		return "CC-LEN8-DLC";
+	case CAN_CTRLMODE_TDC_AUTO:
+		return "TDC-AUTO";
+	case CAN_CTRLMODE_TDC_MANUAL:
+		return "TDC-MANUAL";
+	case CAN_CTRLMODE_RESTRICTED:
+		return "RESTRICTED";
+	case CAN_CTRLMODE_XL:
+		return "XL";
+	case CAN_CTRLMODE_XL_TDC_AUTO:
+		return "XL-TDC-AUTO";
+	case CAN_CTRLMODE_XL_TDC_MANUAL:
+		return "XL-TDC-MANUAL";
+	case CAN_CTRLMODE_XL_TMS:
+		return "TMS";
+	default:
+		return "<unknown>";
+	}
+}
+EXPORT_SYMBOL_GPL(can_get_ctrlmode_str);
+
+static enum can_state can_state_err_to_state(u16 err)
+{
+	if (err < CAN_ERROR_WARNING_THRESHOLD)
+		return CAN_STATE_ERROR_ACTIVE;
+	if (err < CAN_ERROR_PASSIVE_THRESHOLD)
+		return CAN_STATE_ERROR_WARNING;
+	if (err < CAN_BUS_OFF_THRESHOLD)
+		return CAN_STATE_ERROR_PASSIVE;
+
+	return CAN_STATE_BUS_OFF;
+}
+
+void can_state_get_by_berr_counter(const struct net_device *dev,
+				   const struct can_berr_counter *bec,
+				   enum can_state *tx_state,
+				   enum can_state *rx_state)
+{
+	*tx_state = can_state_err_to_state(bec->txerr);
+	*rx_state = can_state_err_to_state(bec->rxerr);
+}
+EXPORT_SYMBOL_GPL(can_state_get_by_berr_counter);
+
+void can_change_state(struct net_device *dev, struct can_frame *cf,
+		      enum can_state tx_state, enum can_state rx_state)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	enum can_state new_state = max(tx_state, rx_state);
+
+	if (unlikely(new_state == priv->state)) {
+		netdev_warn(dev, "%s: oops, state did not change", __func__);
+		return;
+	}
+
+	netdev_dbg(dev, "Controller changed from %s State (%d) into %s State (%d).\n",
+		   can_get_state_str(priv->state), priv->state,
+		   can_get_state_str(new_state), new_state);
+
+	can_update_state_error_stats(dev, new_state);
+	priv->state = new_state;
+
+	if (!cf)
+		return;
+
+	if (unlikely(new_state == CAN_STATE_BUS_OFF)) {
+		cf->can_id |= CAN_ERR_BUSOFF;
+		return;
+	}
+
+	cf->can_id |= CAN_ERR_CRTL;
+	cf->data[1] |= tx_state >= rx_state ?
+		       can_tx_state_to_frame(dev, tx_state) : 0;
+	cf->data[1] |= tx_state <= rx_state ?
+		       can_rx_state_to_frame(dev, rx_state) : 0;
+}
+EXPORT_SYMBOL_GPL(can_change_state);
+
+/* CAN device restart for bus-off recovery */
+static int can_restart(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	struct sk_buff *skb;
+	struct can_frame *cf;
+	int err;
+
+	if (!priv->do_set_mode)
+		return -EOPNOTSUPP;
+
+	if (netif_carrier_ok(dev))
+		netdev_err(dev, "Attempt to restart for bus-off recovery, but carrier is OK?\n");
+
+	/* No synchronization needed because the device is bus-off and
+	 * no messages can come in or go out.
+	 */
+	can_flush_echo_skb(dev);
+
+	/* send restart message upstream */
+	skb = alloc_can_err_skb(dev, &cf);
+	if (skb) {
+		cf->can_id |= CAN_ERR_RESTARTED;
+		netif_rx(skb);
+	}
+
+	/* Now restart the device */
+	netif_carrier_on(dev);
+	err = priv->do_set_mode(dev, CAN_MODE_START);
+	if (err) {
+		netdev_err(dev, "Restart failed, error %pe\n", ERR_PTR(err));
+		netif_carrier_off(dev);
+
+		return err;
+	} else {
+		netdev_dbg(dev, "Restarted\n");
+		priv->can_stats.restarts++;
+	}
+
+	return 0;
+}
+
+static void can_restart_work(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct can_priv *priv = container_of(dwork, struct can_priv,
+					     restart_work);
+
+	can_restart(priv->dev);
+}
+
+int can_restart_now(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	/* A manual restart is only permitted if automatic restart is
+	 * disabled and the device is in the bus-off state
+	 */
+	if (priv->restart_ms)
+		return -EINVAL;
+	if (priv->state != CAN_STATE_BUS_OFF)
+		return -EBUSY;
+
+	cancel_delayed_work_sync(&priv->restart_work);
+
+	return can_restart(dev);
+}
+
+/* CAN bus-off
+ *
+ * This functions should be called when the device goes bus-off to
+ * tell the netif layer that no more packets can be sent or received.
+ * If enabled, a timer is started to trigger bus-off recovery.
+ */
+void can_bus_off(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (priv->restart_ms)
+		netdev_info(dev, "bus-off, scheduling restart in %d ms\n",
+			    priv->restart_ms);
+	else
+		netdev_info(dev, "bus-off\n");
+
+	netif_carrier_off(dev);
+
+	if (priv->restart_ms)
+		schedule_delayed_work(&priv->restart_work,
+				      msecs_to_jiffies(priv->restart_ms));
+}
+EXPORT_SYMBOL_GPL(can_bus_off);
+
+void can_setup(struct net_device *dev)
+{
+	dev->type = ARPHRD_CAN;
+	dev->mtu = CAN_MTU;
+	dev->min_mtu = CAN_MTU;
+	dev->max_mtu = CAN_MTU;
+	dev->hard_header_len = 0;
+	dev->addr_len = 0;
+	dev->tx_queue_len = 10;
+
+	/* New-style flags. */
+	dev->flags = IFF_NOARP;
+	dev->features = NETIF_F_HW_CSUM;
+}
+
+/* Allocate and setup space for the CAN network device */
+struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
+				    unsigned int txqs, unsigned int rxqs)
+{
+	struct can_ml_priv *can_ml;
+	struct net_device *dev;
+	struct can_priv *priv;
+	int size;
+
+	/* We put the driver's priv, the CAN mid layer priv and the
+	 * echo skb into the netdevice's priv. The memory layout for
+	 * the netdev_priv is like this:
+	 *
+	 * +-------------------------+
+	 * | driver's priv           |
+	 * +-------------------------+
+	 * | struct can_ml_priv      |
+	 * +-------------------------+
+	 * | array of struct sk_buff |
+	 * +-------------------------+
+	 */
+
+	size = ALIGN(sizeof_priv, NETDEV_ALIGN) + sizeof(struct can_ml_priv);
+
+	if (echo_skb_max)
+		size = ALIGN(size, sizeof(struct sk_buff *)) +
+			echo_skb_max * sizeof(struct sk_buff *);
+
+	dev = alloc_netdev_mqs(size, "can%d", NET_NAME_UNKNOWN, can_setup,
+			       txqs, rxqs);
+	if (!dev)
+		return NULL;
+
+	priv = netdev_priv(dev);
+	priv->dev = dev;
+
+	can_ml = (void *)priv + ALIGN(sizeof_priv, NETDEV_ALIGN);
+	can_set_ml_priv(dev, can_ml);
+	can_set_cap(dev, CAN_CAP_CC);
+
+	if (echo_skb_max) {
+		priv->echo_skb_max = echo_skb_max;
+		priv->echo_skb = (void *)priv +
+			(size - echo_skb_max * sizeof(struct sk_buff *));
+	}
+
+	priv->state = CAN_STATE_STOPPED;
+
+	INIT_DELAYED_WORK(&priv->restart_work, can_restart_work);
+
+	return dev;
+}
+EXPORT_SYMBOL_GPL(alloc_candev_mqs);
+
+/* Free space of the CAN network device */
+void free_candev(struct net_device *dev)
+{
+	free_netdev(dev);
+}
+EXPORT_SYMBOL_GPL(free_candev);
+
+void can_set_default_mtu(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (priv->ctrlmode & CAN_CTRLMODE_XL) {
+		if (can_is_canxl_dev_mtu(dev->mtu))
+			return;
+		dev->mtu = CANXL_MTU;
+		dev->min_mtu = CANXL_MIN_MTU;
+		dev->max_mtu = CANXL_MAX_MTU;
+	} else if (priv->ctrlmode & CAN_CTRLMODE_FD) {
+		dev->mtu = CANFD_MTU;
+		dev->min_mtu = CANFD_MTU;
+		dev->max_mtu = CANFD_MTU;
+	} else {
+		dev->mtu = CAN_MTU;
+		dev->min_mtu = CAN_MTU;
+		dev->max_mtu = CAN_MTU;
+	}
+}
+
+void can_set_cap_info(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	u32 can_cap;
+
+	if (can_dev_in_xl_only_mode(priv)) {
+		/* XL only mode => no CC/FD capability */
+		can_cap = CAN_CAP_XL;
+	} else {
+		/* mixed mode => CC + FD/XL capability */
+		can_cap = CAN_CAP_CC;
+
+		if (priv->ctrlmode & CAN_CTRLMODE_FD)
+			can_cap |= CAN_CAP_FD;
+
+		if (priv->ctrlmode & CAN_CTRLMODE_XL)
+			can_cap |= CAN_CAP_XL;
+	}
+
+	if (priv->ctrlmode & (CAN_CTRLMODE_LISTENONLY |
+			      CAN_CTRLMODE_RESTRICTED))
+		can_cap |= CAN_CAP_RO;
+
+	can_set_cap(dev, can_cap);
+}
+
+/* helper to define static CAN controller features at device creation time */
+int can_set_static_ctrlmode(struct net_device *dev, u32 static_mode)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	/* alloc_candev() succeeded => netdev_priv() is valid at this point */
+	if (priv->ctrlmode_supported & static_mode) {
+		netdev_warn(dev,
+			    "Controller features can not be supported and static at the same time\n");
+		return -EINVAL;
+	}
+	priv->ctrlmode = static_mode;
+
+	/* override MTU which was set by default in can_setup()? */
+	can_set_default_mtu(dev);
+	can_set_cap_info(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(can_set_static_ctrlmode);
+
+/* generic implementation of netdev_ops::ndo_hwtstamp_get for CAN devices
+ * supporting hardware timestamps
+ */
+int can_hwtstamp_get(struct net_device *netdev,
+		     struct kernel_hwtstamp_config *cfg)
+{
+	cfg->tx_type = HWTSTAMP_TX_ON;
+	cfg->rx_filter = HWTSTAMP_FILTER_ALL;
+
+	return 0;
+}
+EXPORT_SYMBOL(can_hwtstamp_get);
+
+/* generic implementation of netdev_ops::ndo_hwtstamp_set for CAN devices
+ * supporting hardware timestamps
+ */
+int can_hwtstamp_set(struct net_device *netdev,
+		     struct kernel_hwtstamp_config *cfg,
+		     struct netlink_ext_ack *extack)
+{
+	if (cfg->tx_type == HWTSTAMP_TX_ON &&
+	    cfg->rx_filter == HWTSTAMP_FILTER_ALL)
+		return 0;
+	NL_SET_ERR_MSG_MOD(extack, "Only TX on and RX all packets filter supported");
+	return -ERANGE;
+}
+EXPORT_SYMBOL(can_hwtstamp_set);
+
+/* generic implementation of ethtool_ops::get_ts_info for CAN devices
+ * supporting hardware timestamps
+ */
+int can_ethtool_op_get_ts_info_hwts(struct net_device *dev,
+				    struct kernel_ethtool_ts_info *info)
+{
+	info->so_timestamping =
+		SOF_TIMESTAMPING_TX_SOFTWARE |
+		SOF_TIMESTAMPING_TX_HARDWARE |
+		SOF_TIMESTAMPING_RX_HARDWARE |
+		SOF_TIMESTAMPING_RAW_HARDWARE;
+	info->tx_types = BIT(HWTSTAMP_TX_ON);
+	info->rx_filters = BIT(HWTSTAMP_FILTER_ALL);
+
+	return 0;
+}
+EXPORT_SYMBOL(can_ethtool_op_get_ts_info_hwts);
+
+/* Common open function when the device gets opened.
+ *
+ * This function should be called in the open function of the device
+ * driver.
+ */
+int open_candev(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (!priv->bittiming.bitrate) {
+		netdev_err(dev, "bit-timing not yet defined\n");
+		return -EINVAL;
+	}
+
+	/* For CAN FD the data bitrate has to be >= the arbitration bitrate */
+	if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
+	    (!priv->fd.data_bittiming.bitrate ||
+	     priv->fd.data_bittiming.bitrate < priv->bittiming.bitrate)) {
+		netdev_err(dev, "incorrect/missing data bit-timing\n");
+		return -EINVAL;
+	}
+
+	/* Switch carrier on if device was stopped while in bus-off state */
+	if (!netif_carrier_ok(dev))
+		netif_carrier_on(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(open_candev);
+
+#ifdef CONFIG_OF
+/* Common function that can be used to understand the limitation of
+ * a transceiver when it provides no means to determine these limitations
+ * at runtime.
+ */
+void of_can_transceiver(struct net_device *dev)
+{
+	struct device_node *dn;
+	struct can_priv *priv = netdev_priv(dev);
+	struct device_node *np = dev->dev.parent->of_node;
+	int ret;
+
+	dn = of_get_child_by_name(np, "can-transceiver");
+	if (!dn)
+		return;
+
+	ret = of_property_read_u32(dn, "max-bitrate", &priv->bitrate_max);
+	of_node_put(dn);
+	if ((ret && ret != -EINVAL) || (!ret && !priv->bitrate_max))
+		netdev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit.\n");
+}
+EXPORT_SYMBOL_GPL(of_can_transceiver);
+#endif
+
+/* Common close function for cleanup before the device gets closed.
+ *
+ * This function should be called in the close function of the device
+ * driver.
+ */
+void close_candev(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	cancel_delayed_work_sync(&priv->restart_work);
+	can_flush_echo_skb(dev);
+}
+EXPORT_SYMBOL_GPL(close_candev);
+
+static int can_set_termination(struct net_device *ndev, u16 term)
+{
+	struct can_priv *priv = netdev_priv(ndev);
+	int set;
+
+	if (term == priv->termination_gpio_ohms[CAN_TERMINATION_GPIO_ENABLED])
+		set = 1;
+	else
+		set = 0;
+
+	gpiod_set_value_cansleep(priv->termination_gpio, set);
+
+	return 0;
+}
+
+static int can_get_termination(struct net_device *ndev)
+{
+	struct can_priv *priv = netdev_priv(ndev);
+	struct device *dev = ndev->dev.parent;
+	struct gpio_desc *gpio;
+	u32 term;
+	int ret;
+
+	/* Disabling termination by default is the safe choice: Else if many
+	 * bus participants enable it, no communication is possible at all.
+	 */
+	gpio = devm_gpiod_get_optional(dev, "termination", GPIOD_OUT_LOW);
+	if (IS_ERR(gpio))
+		return dev_err_probe(dev, PTR_ERR(gpio),
+				     "Cannot get termination-gpios\n");
+
+	if (!gpio)
+		return 0;
+
+	ret = device_property_read_u32(dev, "termination-ohms", &term);
+	if (ret) {
+		netdev_err(ndev, "Cannot get termination-ohms: %pe\n",
+			   ERR_PTR(ret));
+		return ret;
+	}
+
+	if (term > U16_MAX) {
+		netdev_err(ndev, "Invalid termination-ohms value (%u > %u)\n",
+			   term, U16_MAX);
+		return -EINVAL;
+	}
+
+	priv->termination_const_cnt = ARRAY_SIZE(priv->termination_gpio_ohms);
+	priv->termination_const = priv->termination_gpio_ohms;
+	priv->termination_gpio = gpio;
+	priv->termination_gpio_ohms[CAN_TERMINATION_GPIO_DISABLED] =
+		CAN_TERMINATION_DISABLED;
+	priv->termination_gpio_ohms[CAN_TERMINATION_GPIO_ENABLED] = term;
+	priv->do_set_termination = can_set_termination;
+
+	return 0;
+}
+
+static bool
+can_bittiming_const_valid(const struct can_bittiming_const *btc)
+{
+	if (!btc)
+		return true;
+
+	if (!btc->sjw_max)
+		return false;
+
+	return true;
+}
+
+/* Register the CAN network device */
+int register_candev(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	int err;
+
+	/* Ensure termination_const, termination_const_cnt and
+	 * do_set_termination consistency. All must be either set or
+	 * unset.
+	 */
+	if ((!priv->termination_const != !priv->termination_const_cnt) ||
+	    (!priv->termination_const != !priv->do_set_termination))
+		return -EINVAL;
+
+	if (!priv->bitrate_const != !priv->bitrate_const_cnt)
+		return -EINVAL;
+
+	if (!priv->fd.data_bitrate_const != !priv->fd.data_bitrate_const_cnt)
+		return -EINVAL;
+
+	/* We only support either fixed bit rates or bit timing const. */
+	if ((priv->bitrate_const || priv->fd.data_bitrate_const) &&
+	    (priv->bittiming_const || priv->fd.data_bittiming_const))
+		return -EINVAL;
+
+	if (!can_bittiming_const_valid(priv->bittiming_const) ||
+	    !can_bittiming_const_valid(priv->fd.data_bittiming_const))
+		return -EINVAL;
+
+	if (!priv->termination_const) {
+		err = can_get_termination(dev);
+		if (err)
+			return err;
+	}
+
+	dev->rtnl_link_ops = &can_link_ops;
+	netif_carrier_off(dev);
+
+	return register_netdev(dev);
+}
+EXPORT_SYMBOL_GPL(register_candev);
+
+/* Unregister the CAN network device */
+void unregister_candev(struct net_device *dev)
+{
+	unregister_netdev(dev);
+}
+EXPORT_SYMBOL_GPL(unregister_candev);
+
+/* Test if a network device is a candev based device
+ * and return the can_priv* if so.
+ */
+struct can_priv *safe_candev_priv(struct net_device *dev)
+{
+	if (dev->type != ARPHRD_CAN || dev->rtnl_link_ops != &can_link_ops)
+		return NULL;
+
+	return netdev_priv(dev);
+}
+EXPORT_SYMBOL_GPL(safe_candev_priv);
+
+static __init int can_dev_init(void)
+{
+	int err;
+
+	err = can_netlink_register();
+	if (!err)
+		pr_info("CAN device driver interface\n");
+
+	return err;
+}
+module_init(can_dev_init);
+
+static __exit void can_dev_exit(void)
+{
+	can_netlink_unregister();
+}
+module_exit(can_dev_exit);
+
+MODULE_ALIAS_RTNL_LINK("can");
diff --git a/drivers/net/can/dev/length.c b/drivers/net/can/dev/length.c
new file mode 100644
index 000000000..b7f4d76dd
--- /dev/null
+++ b/drivers/net/can/dev/length.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2012, 2020 Oliver Hartkopp <socketcan@hartkopp.net>
+ */
+
+#include <linux/can/dev.h>
+
+/* CAN DLC to real data length conversion helpers */
+
+static const u8 dlc2len[] = {
+	0, 1, 2, 3, 4, 5, 6, 7,
+	8, 12, 16, 20, 24, 32, 48, 64
+};
+
+/* get data length from raw data length code (DLC) */
+u8 can_fd_dlc2len(u8 dlc)
+{
+	return dlc2len[dlc & 0x0F];
+}
+EXPORT_SYMBOL_GPL(can_fd_dlc2len);
+
+static const u8 len2dlc[] = {
+	0, 1, 2, 3, 4, 5, 6, 7, 8,	/* 0 - 8 */
+	9, 9, 9, 9,			/* 9 - 12 */
+	10, 10, 10, 10,			/* 13 - 16 */
+	11, 11, 11, 11,			/* 17 - 20 */
+	12, 12, 12, 12,			/* 21 - 24 */
+	13, 13, 13, 13, 13, 13, 13, 13,	/* 25 - 32 */
+	14, 14, 14, 14, 14, 14, 14, 14,	/* 33 - 40 */
+	14, 14, 14, 14, 14, 14, 14, 14,	/* 41 - 48 */
+	15, 15, 15, 15, 15, 15, 15, 15,	/* 49 - 56 */
+	15, 15, 15, 15, 15, 15, 15, 15	/* 57 - 64 */
+};
+
+/* map the sanitized data length to an appropriate data length code */
+u8 can_fd_len2dlc(u8 len)
+{
+	/* check for length mapping table size at build time */
+	BUILD_BUG_ON(ARRAY_SIZE(len2dlc) != CANFD_MAX_DLEN + 1);
+
+	if (unlikely(len > CANFD_MAX_DLEN))
+		return CANFD_MAX_DLC;
+
+	return len2dlc[len];
+}
+EXPORT_SYMBOL_GPL(can_fd_len2dlc);
+
+/**
+ * can_skb_get_frame_len() - Calculate the CAN Frame length in bytes
+ * 	of a given skb.
+ * @skb: socket buffer of a CAN message.
+ *
+ * Do a rough calculation: bit stuffing is ignored and length in bits
+ * is rounded up to a length in bytes.
+ *
+ * Rationale: this function is to be used for the BQL functions
+ * (netdev_sent_queue() and netdev_completed_queue()) which expect a
+ * value in bytes. Just using skb->len is insufficient because it will
+ * return the constant value of CAN(FD)_MTU. Doing the bit stuffing
+ * calculation would be too expensive in term of computing resources
+ * for no noticeable gain.
+ *
+ * Remarks: The payload of CAN FD frames with BRS flag are sent at a
+ * different bitrate. Currently, the can-utils canbusload tool does
+ * not support CAN-FD yet and so we could not run any benchmark to
+ * measure the impact. There might be possible improvement here.
+ *
+ * Return: length in bytes.
+ */
+unsigned int can_skb_get_frame_len(const struct sk_buff *skb)
+{
+	const struct canfd_frame *cf = (const struct canfd_frame *)skb->data;
+	u8 len;
+
+	if (can_is_canfd_skb(skb))
+		len = canfd_sanitize_len(cf->len);
+	else if (cf->can_id & CAN_RTR_FLAG)
+		len = 0;
+	else
+		len = cf->len;
+
+	return can_frame_bytes(can_is_canfd_skb(skb), cf->can_id & CAN_EFF_FLAG,
+			       false, len);
+}
+EXPORT_SYMBOL_GPL(can_skb_get_frame_len);
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
new file mode 100644
index 000000000..766d45595
--- /dev/null
+++ b/drivers/net/can/dev/netlink.c
@@ -0,0 +1,1114 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
+ * Copyright (C) 2006 Andrey Volkov, Varma Electronics
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ * Copyright (C) 2021-2025 Vincent Mailhol <mailhol@kernel.org>
+ */
+
+#include <linux/can/dev.h>
+#include <net/rtnetlink.h>
+
+static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
+	[IFLA_CAN_STATE] = { .type = NLA_U32 },
+	[IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
+	[IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
+	[IFLA_CAN_RESTART] = { .type = NLA_U32 },
+	[IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
+	[IFLA_CAN_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) },
+	[IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
+	[IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
+	[IFLA_CAN_DATA_BITTIMING] = { .len = sizeof(struct can_bittiming) },
+	[IFLA_CAN_DATA_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) },
+	[IFLA_CAN_TERMINATION] = { .type = NLA_U16 },
+	[IFLA_CAN_TDC] = { .type = NLA_NESTED },
+	[IFLA_CAN_CTRLMODE_EXT] = { .type = NLA_NESTED },
+	[IFLA_CAN_XL_DATA_BITTIMING] = { .len = sizeof(struct can_bittiming) },
+	[IFLA_CAN_XL_DATA_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) },
+	[IFLA_CAN_XL_TDC] = { .type = NLA_NESTED },
+	[IFLA_CAN_XL_PWM] = { .type = NLA_NESTED },
+};
+
+static const struct nla_policy can_tdc_policy[IFLA_CAN_TDC_MAX + 1] = {
+	[IFLA_CAN_TDC_TDCV_MIN] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCV_MAX] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCO_MIN] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCO_MAX] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCF_MIN] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCF_MAX] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCV] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCO] = { .type = NLA_U32 },
+	[IFLA_CAN_TDC_TDCF] = { .type = NLA_U32 },
+};
+
+static const struct nla_policy can_pwm_policy[IFLA_CAN_PWM_MAX + 1] = {
+	[IFLA_CAN_PWM_PWMS_MIN] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWMS_MAX] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWML_MIN] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWML_MAX] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWMO_MIN] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWMO_MAX] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWMS] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWML] = { .type = NLA_U32 },
+	[IFLA_CAN_PWM_PWMO] = { .type = NLA_U32 },
+};
+
+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_tdc(struct nlattr *data_tdc,
+			    struct netlink_ext_ack *extack, u32 tdc_flags)
+{
+	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_{,XL}_TDC_* flags 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_{,XL}_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_pwm(struct nlattr *data[],
+			    struct netlink_ext_ack *extack, u32 flags)
+{
+	struct nlattr *tb_pwm[IFLA_CAN_PWM_MAX + 1];
+	int err;
+
+	if (!data[IFLA_CAN_XL_PWM])
+		return 0;
+
+	if (!(flags & CAN_CTRLMODE_XL_TMS)) {
+		NL_SET_ERR_MSG(extack, "PWM requires TMS");
+		return -EOPNOTSUPP;
+	}
+
+	err = nla_parse_nested(tb_pwm, IFLA_CAN_PWM_MAX, data[IFLA_CAN_XL_PWM],
+			       can_pwm_policy, extack);
+	if (err)
+		return err;
+
+	if (!tb_pwm[IFLA_CAN_PWM_PWMS] != !tb_pwm[IFLA_CAN_PWM_PWML]) {
+		NL_SET_ERR_MSG(extack,
+			       "Provide either both PWMS and PWML, or none for automatic calculation");
+		return -EOPNOTSUPP;
+	}
+
+	if (tb_pwm[IFLA_CAN_PWM_PWMO] &&
+	    (!tb_pwm[IFLA_CAN_PWM_PWMS] || !tb_pwm[IFLA_CAN_PWM_PWML])) {
+		NL_SET_ERR_MSG(extack, "PWMO requires both PWMS and PWML");
+		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/XL configurations always consist of
+	 * - nominal/arbitration bittiming
+	 * - data bittiming
+	 * - control mode with CAN_CTRLMODE_{FD,XL} set
+	 * - 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 {
+		data_tdc = data[IFLA_CAN_XL_TDC];
+		tdc_flags = flags & CAN_CTRLMODE_XL_TDC_MASK;
+		is_on = flags & CAN_CTRLMODE_XL;
+		type = "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_xl_flags(struct netlink_ext_ack *extack,
+				 u32 masked_flags, u32 mask)
+{
+	if (masked_flags & CAN_CTRLMODE_XL) {
+		if (masked_flags & CAN_CTRLMODE_XL_TMS) {
+			const u32 tms_conflicts_mask = CAN_CTRLMODE_FD |
+				CAN_CTRLMODE_XL_TDC_MASK;
+			u32 tms_conflicts = masked_flags & tms_conflicts_mask;
+
+			if (tms_conflicts) {
+				NL_SET_ERR_MSG_FMT(extack,
+						   "TMS and %s are mutually exclusive",
+						   can_get_ctrlmode_str(tms_conflicts));
+				return -EOPNOTSUPP;
+			}
+		}
+	} else {
+		if (mask & CAN_CTRLMODE_XL_TMS) {
+			NL_SET_ERR_MSG(extack, "TMS requires CAN XL");
+			return -EOPNOTSUPP;
+		}
+	}
+
+	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]);
+
+		flags = cm->flags & cm->mask;
+
+		if ((flags & CAN_CTRLMODE_LISTENONLY) &&
+		    (flags & CAN_CTRLMODE_RESTRICTED)) {
+			NL_SET_ERR_MSG(extack,
+				       "LISTEN-ONLY and RESTRICTED modes are mutually exclusive");
+			return -EOPNOTSUPP;
+		}
+
+		err = can_validate_xl_flags(extack, flags, cm->mask);
+		if (err)
+			return err;
+	}
+
+	err = can_validate_bittiming(data, extack, IFLA_CAN_BITTIMING);
+	if (err)
+		return err;
+
+	err = can_validate_databittiming(data, extack,
+					 IFLA_CAN_DATA_BITTIMING, flags);
+	if (err)
+		return err;
+
+	err = can_validate_databittiming(data, extack,
+					 IFLA_CAN_XL_DATA_BITTIMING, flags);
+	if (err)
+		return err;
+
+	err = can_validate_pwm(data, extack, flags);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+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, deactivated, notsupp, ctrlstatic_missing;
+
+	if (!data[IFLA_CAN_CTRLMODE])
+		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;
+	deactivated = ~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;
+	}
+
+	/* 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 FD was active and is not turned off, check for XL conflicts */
+	if (priv->ctrlmode & CAN_CTRLMODE_FD & ~deactivated) {
+		if (maskedflags & CAN_CTRLMODE_XL_TMS) {
+			NL_SET_ERR_MSG(extack,
+				       "TMS can not be activated while CAN FD is on");
+			return -EOPNOTSUPP;
+		}
+	}
+
+	/* If a top dependency flag is provided, reset all its dependencies */
+	if (cm->mask & CAN_CTRLMODE_FD)
+		priv->ctrlmode &= ~CAN_CTRLMODE_FD_TDC_MASK;
+	if (cm->mask & CAN_CTRLMODE_XL)
+		priv->ctrlmode &= ~(CAN_CTRLMODE_XL_TDC_MASK |
+				    CAN_CTRLMODE_XL_TMS);
+
+	/* clear bits to be modified and copy the flag values */
+	priv->ctrlmode &= ~cm->mask;
+	priv->ctrlmode |= maskedflags;
+
+	/* Wipe potential leftovers from previous CAN FD/XL 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));
+	}
+	if (!(priv->ctrlmode & CAN_CTRLMODE_XL)) {
+		memset(&priv->xl.data_bittiming, 0,
+		       sizeof(priv->fd.data_bittiming));
+		priv->ctrlmode &= ~CAN_CTRLMODE_XL_TDC_MASK;
+		memset(&priv->xl.tdc, 0, sizeof(priv->xl.tdc));
+		memset(&priv->xl.pwm, 0, sizeof(priv->xl.pwm));
+	}
+
+	can_set_default_mtu(dev);
+	can_set_cap_info(dev);
+
+	return 0;
+}
+
+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 = dbt_params->tdc_const;
+	int err;
+
+	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);
+	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;
+	}
+
+	dbt_params->tdc = tdc;
+
+	return 0;
+}
+
+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);
+	struct data_bittiming_params *dbt_params;
+	struct can_bittiming dbt;
+	bool need_tdc_calc = false;
+	u32 tdc_mask;
+	int err;
+
+	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 {
+		data_bittiming = data[IFLA_CAN_XL_DATA_BITTIMING];
+		data_tdc = data[IFLA_CAN_XL_TDC];
+		dbt_params = &priv->xl;
+		tdc_mask = CAN_CTRLMODE_XL_TDC_MASK;
+	}
+
+	if (!data_bittiming)
+		return 0;
+
+	/* 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 (!dbt_params->data_bittiming_const && !dbt_params->do_set_data_bittiming &&
+	    !dbt_params->data_bitrate_const)
+		return -EOPNOTSUPP;
+
+	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;
+
+	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;
+	}
+
+	memset(&dbt_params->tdc, 0, sizeof(dbt_params->tdc));
+	if (data[IFLA_CAN_CTRLMODE]) {
+		struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
+
+		if (fd || !(priv->ctrlmode & CAN_CTRLMODE_XL_TMS))
+			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;
+		}
+	} else if (need_tdc_calc) {
+		/* Neither of TDC parameters nor TDC flags are provided:
+		 * do calculation
+		 */
+		can_calc_tdco(&dbt_params->tdc, dbt_params->tdc_const, &dbt,
+			      tdc_mask, &priv->ctrlmode, priv->ctrlmode_supported);
+	} /* else: both CAN_CTRLMODE_{,XL}_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_pwm_changelink(struct net_device *dev,
+			      const struct nlattr *pwm_nla,
+			      struct netlink_ext_ack *extack)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	const struct can_pwm_const *pwm_const = priv->xl.pwm_const;
+	struct nlattr *tb_pwm[IFLA_CAN_PWM_MAX + 1];
+	struct can_pwm pwm = { 0 };
+	int err;
+
+	if (!(priv->ctrlmode & CAN_CTRLMODE_XL_TMS))
+		return 0;
+
+	if (!pwm_const) {
+		NL_SET_ERR_MSG(extack, "The device does not support PWM");
+		return -EOPNOTSUPP;
+	}
+
+	if (!pwm_nla)
+		return can_calc_pwm(dev, extack);
+
+	err = nla_parse_nested(tb_pwm, IFLA_CAN_PWM_MAX, pwm_nla,
+			       can_pwm_policy, extack);
+	if (err)
+		return err;
+
+	if (tb_pwm[IFLA_CAN_PWM_PWMS]) {
+		pwm.pwms = nla_get_u32(tb_pwm[IFLA_CAN_PWM_PWMS]);
+		if (pwm.pwms < pwm_const->pwms_min ||
+		    pwm.pwms > pwm_const->pwms_max) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "PWMS: %u tqmin is out of range: %u...%u",
+					   pwm.pwms, pwm_const->pwms_min,
+					   pwm_const->pwms_max);
+			return -EINVAL;
+		}
+	}
+
+	if (tb_pwm[IFLA_CAN_PWM_PWML]) {
+		pwm.pwml = nla_get_u32(tb_pwm[IFLA_CAN_PWM_PWML]);
+		if (pwm.pwml < pwm_const->pwml_min ||
+		    pwm.pwml > pwm_const->pwml_max) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "PWML: %u tqmin is out of range: %u...%u",
+					   pwm.pwml, pwm_const->pwml_min,
+					   pwm_const->pwml_max);
+			return -EINVAL;
+		}
+	}
+
+	if (tb_pwm[IFLA_CAN_PWM_PWMO]) {
+		pwm.pwmo = nla_get_u32(tb_pwm[IFLA_CAN_PWM_PWMO]);
+		if (pwm.pwmo < pwm_const->pwmo_min ||
+		    pwm.pwmo > pwm_const->pwmo_max) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "PWMO: %u tqmin is out of range: %u...%u",
+					   pwm.pwmo, pwm_const->pwmo_min,
+					   pwm_const->pwmo_max);
+			return -EINVAL;
+		}
+	}
+
+	err = can_validate_pwm_bittiming(dev, &pwm, extack);
+	if (err)
+		return err;
+
+	priv->xl.pwm = pwm;
+	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();
+
+	err = can_ctrlmode_changelink(dev, data, extack);
+	if (err)
+		return err;
+
+	if (data[IFLA_CAN_BITTIMING]) {
+		struct can_bittiming bt;
+
+		/* Do not allow changing bittiming while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+
+		/* Calculate bittiming parameters based on
+		 * bittiming_const if set, otherwise pass bitrate
+		 * directly via do_set_bitrate(). Bail out if neither
+		 * is given.
+		 */
+		if (!priv->bittiming_const && !priv->do_set_bittiming &&
+		    !priv->bitrate_const)
+			return -EOPNOTSUPP;
+
+		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
+		err = can_get_bittiming(dev, &bt,
+					priv->bittiming_const,
+					priv->bitrate_const,
+					priv->bitrate_const_cnt,
+					extack);
+		if (err)
+			return err;
+
+		if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "arbitration bitrate %u bps surpasses transceiver capabilities of %u bps",
+					   bt.bitrate, priv->bitrate_max);
+			return -EINVAL;
+		}
+
+		memcpy(&priv->bittiming, &bt, sizeof(bt));
+
+		if (priv->do_set_bittiming) {
+			/* Finally, set the bit-timing registers */
+			err = priv->do_set_bittiming(dev);
+			if (err)
+				return err;
+		}
+	}
+
+	if (data[IFLA_CAN_RESTART_MS]) {
+		unsigned int restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
+
+		if (restart_ms != 0 && !priv->do_set_mode) {
+			NL_SET_ERR_MSG(extack,
+				       "Device doesn't support restart from Bus Off");
+			return -EOPNOTSUPP;
+		}
+
+		/* Do not allow changing restart delay while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+		priv->restart_ms = restart_ms;
+	}
+
+	if (data[IFLA_CAN_RESTART]) {
+		if (!priv->do_set_mode) {
+			NL_SET_ERR_MSG(extack,
+				       "Device doesn't support restart from Bus Off");
+			return -EOPNOTSUPP;
+		}
+
+		/* Do not allow a restart while not running */
+		if (!(dev->flags & IFF_UP))
+			return -EINVAL;
+		err = can_restart_now(dev);
+		if (err)
+			return err;
+	}
+
+	/* CAN FD */
+	err = can_dbt_changelink(dev, data, true, extack);
+	if (err)
+		return err;
+
+	/* CAN XL */
+	err = can_dbt_changelink(dev, data, false, extack);
+	if (err)
+		return err;
+	err = can_pwm_changelink(dev, data[IFLA_CAN_XL_PWM], 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) {
+			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++) {
+			if (termval == priv->termination_const[i])
+				break;
+		}
+		if (i >= num_term)
+			return -EINVAL;
+
+		/* Finally, set the termination value */
+		err = priv->do_set_termination(dev, termval);
+		if (err)
+			return err;
+
+		priv->termination = termval;
+	}
+
+	return 0;
+}
+
+static size_t can_tdc_get_size(struct data_bittiming_params *dbt_params,
+			       u32 tdc_flags)
+{
+	bool tdc_manual = tdc_flags & CAN_CTRLMODE_TDC_MANUAL_MASK;
+	size_t size;
+
+	if (!dbt_params->tdc_const)
+		return 0;
+
+	size = nla_total_size(0);			/* nest IFLA_CAN_TDC */
+	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 (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 (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 (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_{,XL}_DATA_BITTIMING */
+		size += nla_total_size(sizeof(dbt_params->data_bittiming));
+	if (dbt_params->data_bittiming_const)		/* IFLA_CAN_{,XL}_DATA_BITTIMING_CONST */
+		size += nla_total_size(sizeof(*dbt_params->data_bittiming_const));
+	if (dbt_params->data_bitrate_const)		/* IFLA_CAN_{,XL}_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_{,XL}_TDC */
+
+	return size;
+}
+
+static size_t can_ctrlmode_ext_get_size(void)
+{
+	return nla_total_size(0) +		/* nest IFLA_CAN_CTRLMODE_EXT */
+		nla_total_size(sizeof(u32));	/* IFLA_CAN_CTRLMODE_SUPPORTED */
+}
+
+static size_t can_pwm_get_size(const struct can_pwm_const *pwm_const,
+			       bool pwm_on)
+{
+	size_t size;
+
+	if (!pwm_const || !pwm_on)
+		return 0;
+
+	size = nla_total_size(0);			/* nest IFLA_CAN_PWM */
+
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWMS_MIN */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWMS_MAX */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWML_MIN */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWML_MAX */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWMO_MIN */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWMO_MAX */
+
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWMS */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWML */
+	size += nla_total_size(sizeof(u32));		/* IFLA_CAN_PWM_PWMO */
+
+	return size;
+}
+
+static size_t can_get_size(const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	size_t size = 0;
+
+	if (priv->bittiming.bitrate)				/* IFLA_CAN_BITTIMING */
+		size += nla_total_size(sizeof(struct can_bittiming));
+	if (priv->bittiming_const)				/* IFLA_CAN_BITTIMING_CONST */
+		size += nla_total_size(sizeof(struct can_bittiming_const));
+	size += nla_total_size(sizeof(struct can_clock));	/* IFLA_CAN_CLOCK */
+	size += nla_total_size(sizeof(u32));			/* IFLA_CAN_STATE */
+	size += nla_total_size(sizeof(struct can_ctrlmode));	/* IFLA_CAN_CTRLMODE */
+	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->termination_const) {
+		size += nla_total_size(sizeof(priv->termination));		/* IFLA_CAN_TERMINATION */
+		size += nla_total_size(sizeof(*priv->termination_const) *	/* IFLA_CAN_TERMINATION_CONST */
+				       priv->termination_const_cnt);
+	}
+	if (priv->bitrate_const)				/* IFLA_CAN_BITRATE_CONST */
+		size += nla_total_size(sizeof(*priv->bitrate_const) *
+				       priv->bitrate_const_cnt);
+	size += sizeof(priv->bitrate_max);			/* IFLA_CAN_BITRATE_MAX */
+	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);
+
+	size += can_data_bittiming_get_size(&priv->xl,
+					    priv->ctrlmode & CAN_CTRLMODE_XL_TDC_MASK);
+	size += can_pwm_get_size(priv->xl.pwm_const,		/* IFLA_CAN_XL_PWM */
+				 priv->ctrlmode & CAN_CTRLMODE_XL_TMS);
+
+	return size;
+}
+
+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 can_priv *priv = netdev_priv(dev);
+	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 {
+		dbt_params = &priv->xl;
+		tdc_is_enabled = can_xl_tdc_is_enabled(priv);
+		tdc_manual = priv->ctrlmode & CAN_CTRLMODE_XL_TDC_MANUAL;
+	}
+	tdc_const = dbt_params->tdc_const;
+	tdc = &dbt_params->tdc;
+
+	if (!tdc_const)
+		return 0;
+
+	nest = nla_nest_start(skb, ifla_can_tdc);
+	if (!nest)
+		return -EMSGSIZE;
+
+	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;
+	if (nla_put_u32(skb, IFLA_CAN_TDC_TDCO_MIN, tdc_const->tdco_min) ||
+	    nla_put_u32(skb, IFLA_CAN_TDC_TDCO_MAX, tdc_const->tdco_max))
+		goto err_cancel;
+	if (tdc_const->tdcf_max &&
+	    (nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MIN, tdc_const->tdcf_min) ||
+	     nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MAX, tdc_const->tdcf_max)))
+		goto err_cancel;
+
+	if (tdc_is_enabled) {
+		u32 tdcv;
+		int err = -EINVAL;
+
+		if (tdc_manual) {
+			tdcv = tdc->tdcv;
+			err = 0;
+		} 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;
+		if (nla_put_u32(skb, IFLA_CAN_TDC_TDCO, tdc->tdco))
+			goto err_cancel;
+		if (tdc_const->tdcf_max &&
+		    nla_put_u32(skb, IFLA_CAN_TDC_TDCF, tdc->tdcf))
+			goto err_cancel;
+	}
+
+	nla_nest_end(skb, nest);
+	return 0;
+
+err_cancel:
+	nla_nest_cancel(skb, nest);
+	return -EMSGSIZE;
+}
+
+static int can_pwm_fill_info(struct sk_buff *skb, const struct can_priv *priv)
+{
+	const struct can_pwm_const *pwm_const = priv->xl.pwm_const;
+	const struct can_pwm *pwm = &priv->xl.pwm;
+	struct nlattr *nest;
+
+	if (!pwm_const)
+		return 0;
+
+	nest = nla_nest_start(skb, IFLA_CAN_XL_PWM);
+	if (!nest)
+		return -EMSGSIZE;
+
+	if (nla_put_u32(skb, IFLA_CAN_PWM_PWMS_MIN, pwm_const->pwms_min) ||
+	    nla_put_u32(skb, IFLA_CAN_PWM_PWMS_MAX, pwm_const->pwms_max) ||
+	    nla_put_u32(skb, IFLA_CAN_PWM_PWML_MIN, pwm_const->pwml_min) ||
+	    nla_put_u32(skb, IFLA_CAN_PWM_PWML_MAX, pwm_const->pwml_max) ||
+	    nla_put_u32(skb, IFLA_CAN_PWM_PWMO_MIN, pwm_const->pwmo_min) ||
+	    nla_put_u32(skb, IFLA_CAN_PWM_PWMO_MAX, pwm_const->pwmo_max))
+		goto err_cancel;
+
+	if (priv->ctrlmode & CAN_CTRLMODE_XL_TMS) {
+		if (nla_put_u32(skb, IFLA_CAN_PWM_PWMS, pwm->pwms) ||
+		    nla_put_u32(skb, IFLA_CAN_PWM_PWML, pwm->pwml) ||
+		    nla_put_u32(skb, IFLA_CAN_PWM_PWMO, pwm->pwmo))
+			goto err_cancel;
+	}
+
+	nla_nest_end(skb, nest);
+	return 0;
+
+err_cancel:
+	nla_nest_cancel(skb, nest);
+	return -EMSGSIZE;
+}
+
+static int can_ctrlmode_ext_fill_info(struct sk_buff *skb,
+				      const struct can_priv *priv)
+{
+	struct nlattr *nest;
+
+	nest = nla_nest_start(skb, IFLA_CAN_CTRLMODE_EXT);
+	if (!nest)
+		return -EMSGSIZE;
+
+	if (nla_put_u32(skb, IFLA_CAN_CTRLMODE_SUPPORTED,
+			priv->ctrlmode_supported)) {
+		nla_nest_cancel(skb, nest);
+		return -EMSGSIZE;
+	}
+
+	nla_nest_end(skb, nest);
+	return 0;
+}
+
+static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	struct can_ctrlmode cm = {.flags = priv->ctrlmode};
+	struct can_berr_counter bec = { };
+	enum can_state state = priv->state;
+
+	if (priv->do_get_state)
+		priv->do_get_state(dev, &state);
+
+	if (can_bittiming_fill_info(skb, IFLA_CAN_BITTIMING,
+				    &priv->bittiming) ||
+
+	    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) ||
+	    nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
+	    nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
+
+	    (priv->do_get_berr_counter &&
+	     !priv->do_get_berr_counter(dev, &bec) &&
+	     nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
+
+	    can_bittiming_fill_info(skb, IFLA_CAN_DATA_BITTIMING,
+				    &priv->fd.data_bittiming) ||
+
+	    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) ||
+	      nla_put(skb, IFLA_CAN_TERMINATION_CONST,
+		      sizeof(*priv->termination_const) *
+		      priv->termination_const_cnt,
+		      priv->termination_const))) ||
+
+	    can_bitrate_const_fill_info(skb, IFLA_CAN_BITRATE_CONST,
+					priv->bitrate_const,
+					priv->bitrate_const_cnt) ||
+
+	    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, IFLA_CAN_TDC) ||
+
+	    can_ctrlmode_ext_fill_info(skb, priv) ||
+
+	    can_bittiming_fill_info(skb, IFLA_CAN_XL_DATA_BITTIMING,
+				    &priv->xl.data_bittiming) ||
+
+	    can_bittiming_const_fill_info(skb, IFLA_CAN_XL_DATA_BITTIMING_CONST,
+					  priv->xl.data_bittiming_const) ||
+
+	    can_bitrate_const_fill_info(skb, IFLA_CAN_XL_DATA_BITRATE_CONST,
+					priv->xl.data_bitrate_const,
+					priv->xl.data_bitrate_const_cnt) ||
+
+	    can_tdc_fill_info(skb, dev, IFLA_CAN_XL_TDC) ||
+
+	    can_pwm_fill_info(skb, priv)
+	    )
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+static size_t can_get_xstats_size(const struct net_device *dev)
+{
+	return sizeof(struct can_device_stats);
+}
+
+static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (nla_put(skb, IFLA_INFO_XSTATS,
+		    sizeof(priv->can_stats), &priv->can_stats))
+		goto nla_put_failure;
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static int can_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
+		       struct netlink_ext_ack *extack)
+{
+	return -EOPNOTSUPP;
+}
+
+static void can_dellink(struct net_device *dev, struct list_head *head)
+{
+}
+
+struct rtnl_link_ops can_link_ops __read_mostly = {
+	.kind		= "can",
+	.netns_refund	= true,
+	.maxtype	= IFLA_CAN_MAX,
+	.policy		= can_policy,
+	.setup		= can_setup,
+	.validate	= can_validate,
+	.newlink	= can_newlink,
+	.changelink	= can_changelink,
+	.dellink	= can_dellink,
+	.get_size	= can_get_size,
+	.fill_info	= can_fill_info,
+	.get_xstats_size = can_get_xstats_size,
+	.fill_xstats	= can_fill_xstats,
+};
+
+int can_netlink_register(void)
+{
+	return rtnl_link_register(&can_link_ops);
+}
+
+void can_netlink_unregister(void)
+{
+	rtnl_link_unregister(&can_link_ops);
+}
diff --git a/drivers/net/can/dev/rx-offload.c b/drivers/net/can/dev/rx-offload.c
new file mode 100644
index 000000000..46e7b6db4
--- /dev/null
+++ b/drivers/net/can/dev/rx-offload.c
@@ -0,0 +1,427 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2014      Protonic Holland,
+ *                         David Jander
+ * Copyright (C) 2014-2021, 2023 Pengutronix,
+ *                         Marc Kleine-Budde <kernel@pengutronix.de>
+ */
+
+#include <linux/can/dev.h>
+#include <linux/can/rx-offload.h>
+
+struct can_rx_offload_cb {
+	u32 timestamp;
+};
+
+static inline struct can_rx_offload_cb *
+can_rx_offload_get_cb(struct sk_buff *skb)
+{
+	BUILD_BUG_ON(sizeof(struct can_rx_offload_cb) > sizeof(skb->cb));
+
+	return (struct can_rx_offload_cb *)skb->cb;
+}
+
+static inline bool
+can_rx_offload_le(struct can_rx_offload *offload,
+		  unsigned int a, unsigned int b)
+{
+	if (offload->inc)
+		return a <= b;
+	else
+		return a >= b;
+}
+
+static inline unsigned int
+can_rx_offload_inc(struct can_rx_offload *offload, unsigned int *val)
+{
+	if (offload->inc)
+		return (*val)++;
+	else
+		return (*val)--;
+}
+
+static int can_rx_offload_napi_poll(struct napi_struct *napi, int quota)
+{
+	struct can_rx_offload *offload = container_of(napi,
+						      struct can_rx_offload,
+						      napi);
+	struct net_device *dev = offload->dev;
+	struct net_device_stats *stats = &dev->stats;
+	struct sk_buff *skb;
+	int work_done = 0;
+
+	while ((work_done < quota) &&
+	       (skb = skb_dequeue(&offload->skb_queue))) {
+		struct can_frame *cf = (struct can_frame *)skb->data;
+
+		work_done++;
+		if (!(cf->can_id & CAN_ERR_FLAG)) {
+			stats->rx_packets++;
+			if (!(cf->can_id & CAN_RTR_FLAG))
+				stats->rx_bytes += cf->len;
+		}
+		netif_receive_skb(skb);
+	}
+
+	if (work_done < quota) {
+		napi_complete_done(napi, work_done);
+
+		/* Check if there was another interrupt */
+		if (!skb_queue_empty(&offload->skb_queue))
+			napi_schedule(&offload->napi);
+	}
+
+	return work_done;
+}
+
+static inline void
+__skb_queue_add_sort(struct sk_buff_head *head, struct sk_buff *new,
+		     int (*compare)(struct sk_buff *a, struct sk_buff *b))
+{
+	struct sk_buff *pos, *insert = NULL;
+
+	skb_queue_reverse_walk(head, pos) {
+		const struct can_rx_offload_cb *cb_pos, *cb_new;
+
+		cb_pos = can_rx_offload_get_cb(pos);
+		cb_new = can_rx_offload_get_cb(new);
+
+		netdev_dbg(new->dev,
+			   "%s: pos=0x%08x, new=0x%08x, diff=%10d, queue_len=%d\n",
+			   __func__,
+			   cb_pos->timestamp, cb_new->timestamp,
+			   cb_new->timestamp - cb_pos->timestamp,
+			   skb_queue_len(head));
+
+		if (compare(pos, new) < 0)
+			continue;
+		insert = pos;
+		break;
+	}
+	if (!insert)
+		__skb_queue_head(head, new);
+	else
+		__skb_queue_after(head, insert, new);
+}
+
+static int can_rx_offload_compare(struct sk_buff *a, struct sk_buff *b)
+{
+	const struct can_rx_offload_cb *cb_a, *cb_b;
+
+	cb_a = can_rx_offload_get_cb(a);
+	cb_b = can_rx_offload_get_cb(b);
+
+	/* Subtract two u32 and return result as int, to keep
+	 * difference steady around the u32 overflow.
+	 */
+	return cb_b->timestamp - cb_a->timestamp;
+}
+
+/**
+ * can_rx_offload_offload_one() - Read one CAN frame from HW
+ * @offload: pointer to rx_offload context
+ * @n: number of mailbox to read
+ *
+ * The task of this function is to read a CAN frame from mailbox @n
+ * from the device and return the mailbox's content as a struct
+ * sk_buff.
+ *
+ * If the struct can_rx_offload::skb_queue exceeds the maximal queue
+ * length (struct can_rx_offload::skb_queue_len_max) or no skb can be
+ * allocated, the mailbox contents is discarded by reading it into an
+ * overflow buffer. This way the mailbox is marked as free by the
+ * driver.
+ *
+ * Return: A pointer to skb containing the CAN frame on success.
+ *
+ *         NULL if the mailbox @n is empty.
+ *
+ *         ERR_PTR() in case of an error
+ */
+static struct sk_buff *
+can_rx_offload_offload_one(struct can_rx_offload *offload, unsigned int n)
+{
+	struct sk_buff *skb;
+	struct can_rx_offload_cb *cb;
+	bool drop = false;
+	u32 timestamp;
+
+	/* If queue is full drop frame */
+	if (unlikely(skb_queue_len(&offload->skb_queue) >
+		     offload->skb_queue_len_max))
+		drop = true;
+
+	skb = offload->mailbox_read(offload, n, &timestamp, drop);
+	/* Mailbox was empty. */
+	if (unlikely(!skb))
+		return NULL;
+
+	/* There was a problem reading the mailbox, propagate
+	 * error value.
+	 */
+	if (IS_ERR(skb)) {
+		offload->dev->stats.rx_dropped++;
+		offload->dev->stats.rx_fifo_errors++;
+
+		return skb;
+	}
+
+	/* Mailbox was read. */
+	cb = can_rx_offload_get_cb(skb);
+	cb->timestamp = timestamp;
+
+	return skb;
+}
+
+int can_rx_offload_irq_offload_timestamp(struct can_rx_offload *offload,
+					 u64 pending)
+{
+	unsigned int i;
+	int received = 0;
+
+	for (i = offload->mb_first;
+	     can_rx_offload_le(offload, i, offload->mb_last);
+	     can_rx_offload_inc(offload, &i)) {
+		struct sk_buff *skb;
+
+		if (!(pending & BIT_ULL(i)))
+			continue;
+
+		skb = can_rx_offload_offload_one(offload, i);
+		if (IS_ERR_OR_NULL(skb))
+			continue;
+
+		__skb_queue_add_sort(&offload->skb_irq_queue, skb,
+				     can_rx_offload_compare);
+		received++;
+	}
+
+	return received;
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_timestamp);
+
+int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload)
+{
+	struct sk_buff *skb;
+	int received = 0;
+
+	while (1) {
+		skb = can_rx_offload_offload_one(offload, 0);
+		if (IS_ERR(skb))
+			continue;
+		if (!skb)
+			break;
+
+		__skb_queue_tail(&offload->skb_irq_queue, skb);
+		received++;
+	}
+
+	return received;
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_fifo);
+
+int can_rx_offload_queue_timestamp(struct can_rx_offload *offload,
+				   struct sk_buff *skb, u32 timestamp)
+{
+	struct can_rx_offload_cb *cb;
+
+	if (skb_queue_len(&offload->skb_queue) >
+	    offload->skb_queue_len_max) {
+		dev_kfree_skb_any(skb);
+		return -ENOBUFS;
+	}
+
+	cb = can_rx_offload_get_cb(skb);
+	cb->timestamp = timestamp;
+
+	__skb_queue_add_sort(&offload->skb_irq_queue, skb,
+			     can_rx_offload_compare);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_queue_timestamp);
+
+unsigned int
+can_rx_offload_get_echo_skb_queue_timestamp(struct can_rx_offload *offload,
+					    unsigned int idx, u32 timestamp,
+					    unsigned int *frame_len_ptr)
+{
+	struct net_device *dev = offload->dev;
+	struct net_device_stats *stats = &dev->stats;
+	struct sk_buff *skb;
+	unsigned int len;
+	int err;
+
+	skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr);
+	if (!skb)
+		return 0;
+
+	err = can_rx_offload_queue_timestamp(offload, skb, timestamp);
+	if (err) {
+		stats->rx_errors++;
+		stats->tx_fifo_errors++;
+	}
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_get_echo_skb_queue_timestamp);
+
+int can_rx_offload_queue_tail(struct can_rx_offload *offload,
+			      struct sk_buff *skb)
+{
+	if (skb_queue_len(&offload->skb_queue) >
+	    offload->skb_queue_len_max) {
+		dev_kfree_skb_any(skb);
+		return -ENOBUFS;
+	}
+
+	__skb_queue_tail(&offload->skb_irq_queue, skb);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_queue_tail);
+
+unsigned int
+can_rx_offload_get_echo_skb_queue_tail(struct can_rx_offload *offload,
+				       unsigned int idx,
+				       unsigned int *frame_len_ptr)
+{
+	struct net_device *dev = offload->dev;
+	struct net_device_stats *stats = &dev->stats;
+	struct sk_buff *skb;
+	unsigned int len;
+	int err;
+
+	skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr);
+	if (!skb)
+		return 0;
+
+	err = can_rx_offload_queue_tail(offload, skb);
+	if (err) {
+		stats->rx_errors++;
+		stats->tx_fifo_errors++;
+	}
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_get_echo_skb_queue_tail);
+
+void can_rx_offload_irq_finish(struct can_rx_offload *offload)
+{
+	unsigned long flags;
+	int queue_len;
+
+	if (skb_queue_empty_lockless(&offload->skb_irq_queue))
+		return;
+
+	spin_lock_irqsave(&offload->skb_queue.lock, flags);
+	skb_queue_splice_tail_init(&offload->skb_irq_queue, &offload->skb_queue);
+	spin_unlock_irqrestore(&offload->skb_queue.lock, flags);
+
+	queue_len = skb_queue_len(&offload->skb_queue);
+	if (queue_len > offload->skb_queue_len_max / 8)
+		netdev_dbg(offload->dev, "%s: queue_len=%d\n",
+			   __func__, queue_len);
+
+	napi_schedule(&offload->napi);
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_irq_finish);
+
+void can_rx_offload_threaded_irq_finish(struct can_rx_offload *offload)
+{
+	unsigned long flags;
+	int queue_len;
+
+	if (skb_queue_empty_lockless(&offload->skb_irq_queue))
+		return;
+
+	spin_lock_irqsave(&offload->skb_queue.lock, flags);
+	skb_queue_splice_tail_init(&offload->skb_irq_queue, &offload->skb_queue);
+	spin_unlock_irqrestore(&offload->skb_queue.lock, flags);
+
+	queue_len = skb_queue_len(&offload->skb_queue);
+	if (queue_len > offload->skb_queue_len_max / 8)
+		netdev_dbg(offload->dev, "%s: queue_len=%d\n",
+			   __func__, queue_len);
+
+	local_bh_disable();
+	napi_schedule(&offload->napi);
+	local_bh_enable();
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_threaded_irq_finish);
+
+static int can_rx_offload_init_queue(struct net_device *dev,
+				     struct can_rx_offload *offload,
+				     unsigned int weight)
+{
+	offload->dev = dev;
+
+	/* Limit queue len to 4x the weight (rounded to next power of two) */
+	offload->skb_queue_len_max = 2 << fls(weight);
+	offload->skb_queue_len_max *= 4;
+	skb_queue_head_init(&offload->skb_queue);
+	__skb_queue_head_init(&offload->skb_irq_queue);
+
+	netif_napi_add_weight(dev, &offload->napi, can_rx_offload_napi_poll,
+			      weight);
+
+	dev_dbg(dev->dev.parent, "%s: skb_queue_len_max=%d\n",
+		__func__, offload->skb_queue_len_max);
+
+	return 0;
+}
+
+int can_rx_offload_add_timestamp(struct net_device *dev,
+				 struct can_rx_offload *offload)
+{
+	unsigned int weight;
+
+	if (offload->mb_first > BITS_PER_LONG_LONG ||
+	    offload->mb_last > BITS_PER_LONG_LONG || !offload->mailbox_read)
+		return -EINVAL;
+
+	if (offload->mb_first < offload->mb_last) {
+		offload->inc = true;
+		weight = offload->mb_last - offload->mb_first;
+	} else {
+		offload->inc = false;
+		weight = offload->mb_first - offload->mb_last;
+	}
+
+	return can_rx_offload_init_queue(dev, offload, weight);
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_add_timestamp);
+
+int can_rx_offload_add_fifo(struct net_device *dev,
+			    struct can_rx_offload *offload, unsigned int weight)
+{
+	if (!offload->mailbox_read)
+		return -EINVAL;
+
+	return can_rx_offload_init_queue(dev, offload, weight);
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_add_fifo);
+
+int can_rx_offload_add_manual(struct net_device *dev,
+			      struct can_rx_offload *offload,
+			      unsigned int weight)
+{
+	if (offload->mailbox_read)
+		return -EINVAL;
+
+	return can_rx_offload_init_queue(dev, offload, weight);
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_add_manual);
+
+void can_rx_offload_enable(struct can_rx_offload *offload)
+{
+	napi_enable(&offload->napi);
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_enable);
+
+void can_rx_offload_del(struct can_rx_offload *offload)
+{
+	netif_napi_del(&offload->napi);
+	skb_queue_purge(&offload->skb_queue);
+	__skb_queue_purge(&offload->skb_irq_queue);
+}
+EXPORT_SYMBOL_GPL(can_rx_offload_del);
diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c
new file mode 100644
index 000000000..95fcdc102
--- /dev/null
+++ b/drivers/net/can/dev/skb.c
@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
+ * Copyright (C) 2006 Andrey Volkov, Varma Electronics
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ */
+
+#include <linux/can/dev.h>
+#include <linux/module.h>
+#include <net/can.h>
+
+#define MOD_DESC "CAN device driver interface"
+
+MODULE_DESCRIPTION(MOD_DESC);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
+
+/* Local echo of CAN messages
+ *
+ * CAN network devices *should* support a local echo functionality
+ * (see Documentation/networking/can.rst). To test the handling of CAN
+ * interfaces that do not support the local echo both driver types are
+ * implemented. In the case that the driver does not support the echo
+ * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core
+ * to perform the echo as a fallback solution.
+ */
+void can_flush_echo_skb(struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	struct net_device_stats *stats = &dev->stats;
+	int i;
+
+	for (i = 0; i < priv->echo_skb_max; i++) {
+		if (priv->echo_skb[i]) {
+			kfree_skb(priv->echo_skb[i]);
+			priv->echo_skb[i] = NULL;
+			stats->tx_dropped++;
+			stats->tx_aborted_errors++;
+		}
+	}
+}
+
+/* Put the skb on the stack to be looped backed locally lateron
+ *
+ * The function is typically called in the start_xmit function
+ * of the device driver. The driver must protect access to
+ * priv->echo_skb, if necessary.
+ */
+int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+		     unsigned int idx, unsigned int frame_len)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	struct can_skb_ext *csx;
+
+	if (idx >= priv->echo_skb_max) {
+		netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
+			   __func__, idx, priv->echo_skb_max);
+		return -EINVAL;
+	}
+
+	/* check flag whether this packet has to be looped back */
+	if (!(dev->flags & IFF_ECHO) ||
+	    (skb->protocol != htons(ETH_P_CAN) &&
+	     skb->protocol != htons(ETH_P_CANFD) &&
+	     skb->protocol != htons(ETH_P_CANXL))) {
+		kfree_skb(skb);
+		return 0;
+	}
+
+	if (!priv->echo_skb[idx]) {
+		skb = can_create_echo_skb(skb);
+		if (!skb)
+			return -ENOMEM;
+
+		/* make settings for echo to reduce code in irq context */
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+		skb->dev = dev;
+
+		/* save frame_len to reuse it when transmission is completed */
+		csx = can_skb_ext_find(skb);
+		if (csx)
+			csx->can_framelen = frame_len;
+
+		if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)
+			skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
+
+		skb_tx_timestamp(skb);
+
+		/* save this skb for tx interrupt echo handling */
+		priv->echo_skb[idx] = skb;
+	} else {
+		/* locking problem with netif_stop_queue() ?? */
+		netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx);
+		kfree_skb(skb);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(can_put_echo_skb);
+
+struct sk_buff *
+__can_get_echo_skb(struct net_device *dev, unsigned int idx,
+		   unsigned int *len_ptr, unsigned int *frame_len_ptr)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (idx >= priv->echo_skb_max) {
+		netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
+			   __func__, idx, priv->echo_skb_max);
+		return NULL;
+	}
+
+	if (priv->echo_skb[idx]) {
+		/* Using "struct canfd_frame::len" for the frame
+		 * length is supported on both CAN and CANFD frames.
+		 */
+		struct sk_buff *skb = priv->echo_skb[idx];
+		struct can_skb_ext *csx;
+
+		if (skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)
+			skb_tstamp_tx(skb, skb_hwtstamps(skb));
+
+		/* get the real payload length for netdev statistics */
+		*len_ptr = can_skb_get_data_len(skb);
+
+		if (frame_len_ptr) {
+			csx = can_skb_ext_find(skb);
+			if (csx)
+				*frame_len_ptr = csx->can_framelen;
+			else
+				*frame_len_ptr = 0;
+		}
+
+		priv->echo_skb[idx] = NULL;
+
+		if (skb->pkt_type == PACKET_LOOPBACK) {
+			skb->pkt_type = PACKET_BROADCAST;
+		} else {
+			dev_consume_skb_any(skb);
+			return NULL;
+		}
+
+		return skb;
+	}
+
+	return NULL;
+}
+
+/* Get the skb from the stack and loop it back locally
+ *
+ * The function is typically called when the TX done interrupt
+ * is handled in the device driver. The driver must protect
+ * access to priv->echo_skb, if necessary.
+ */
+unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx,
+			      unsigned int *frame_len_ptr)
+{
+	struct sk_buff *skb;
+	unsigned int len;
+
+	skb = __can_get_echo_skb(dev, idx, &len, frame_len_ptr);
+	if (!skb)
+		return 0;
+
+	skb_get(skb);
+	if (netif_rx(skb) == NET_RX_SUCCESS)
+		dev_consume_skb_any(skb);
+	else
+		dev_kfree_skb_any(skb);
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(can_get_echo_skb);
+
+/* Remove the skb from the stack and free it.
+ *
+ * The function is typically called when TX failed.
+ */
+void can_free_echo_skb(struct net_device *dev, unsigned int idx,
+		       unsigned int *frame_len_ptr)
+{
+	struct can_priv *priv = netdev_priv(dev);
+
+	if (idx >= priv->echo_skb_max) {
+		netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
+			   __func__, idx, priv->echo_skb_max);
+		return;
+	}
+
+	if (priv->echo_skb[idx]) {
+		struct sk_buff *skb = priv->echo_skb[idx];
+		struct can_skb_ext *csx;
+
+		if (frame_len_ptr) {
+			csx = can_skb_ext_find(skb);
+			if (csx)
+				*frame_len_ptr = csx->can_framelen;
+			else
+				*frame_len_ptr = 0;
+		}
+
+		dev_kfree_skb_any(skb);
+		priv->echo_skb[idx] = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(can_free_echo_skb);
+
+/* fill common values for CAN sk_buffs */
+static void init_can_skb(struct sk_buff *skb)
+{
+	skb->pkt_type = PACKET_BROADCAST;
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+}
+
+struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
+{
+	struct sk_buff *skb;
+	struct can_skb_ext *csx;
+
+	skb = netdev_alloc_skb(dev, sizeof(struct can_frame));
+	if (unlikely(!skb))
+		goto out_error_cc;
+
+	csx = can_skb_ext_add(skb);
+	if (!csx) {
+		kfree_skb(skb);
+		goto out_error_cc;
+	}
+
+	skb->protocol = htons(ETH_P_CAN);
+	init_can_skb(skb);
+	csx->can_iif = dev->ifindex;
+
+	*cf = skb_put_zero(skb, sizeof(struct can_frame));
+
+	return skb;
+
+out_error_cc:
+	*cf = NULL;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(alloc_can_skb);
+
+struct sk_buff *alloc_canfd_skb(struct net_device *dev,
+				struct canfd_frame **cfd)
+{
+	struct sk_buff *skb;
+	struct can_skb_ext *csx;
+
+	skb = netdev_alloc_skb(dev, sizeof(struct canfd_frame));
+	if (unlikely(!skb))
+		goto out_error_fd;
+
+	csx = can_skb_ext_add(skb);
+	if (!csx) {
+		kfree_skb(skb);
+		goto out_error_fd;
+	}
+
+	skb->protocol = htons(ETH_P_CANFD);
+	init_can_skb(skb);
+	csx->can_iif = dev->ifindex;
+
+	*cfd = skb_put_zero(skb, sizeof(struct canfd_frame));
+
+	/* set CAN FD flag by default */
+	(*cfd)->flags = CANFD_FDF;
+
+	return skb;
+
+out_error_fd:
+	*cfd = NULL;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(alloc_canfd_skb);
+
+struct sk_buff *alloc_canxl_skb(struct net_device *dev,
+				struct canxl_frame **cxl,
+				unsigned int data_len)
+{
+	struct sk_buff *skb;
+	struct can_skb_ext *csx;
+
+	if (data_len < CANXL_MIN_DLEN || data_len > CANXL_MAX_DLEN)
+		goto out_error_xl;
+
+	skb = netdev_alloc_skb(dev, CANXL_HDR_SIZE + data_len);
+	if (unlikely(!skb))
+		goto out_error_xl;
+
+	csx = can_skb_ext_add(skb);
+	if (!csx) {
+		kfree_skb(skb);
+		goto out_error_xl;
+	}
+
+	skb->protocol = htons(ETH_P_CANXL);
+	init_can_skb(skb);
+	csx->can_iif = dev->ifindex;
+
+	*cxl = skb_put_zero(skb, CANXL_HDR_SIZE + data_len);
+
+	/* set CAN XL flag and length information by default */
+	(*cxl)->flags = CANXL_XLF;
+	(*cxl)->len = data_len;
+
+	return skb;
+
+out_error_xl:
+	*cxl = NULL;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(alloc_canxl_skb);
+
+struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
+{
+	struct sk_buff *skb;
+
+	skb = alloc_can_skb(dev, cf);
+	if (unlikely(!skb))
+		return NULL;
+
+	(*cf)->can_id = CAN_ERR_FLAG;
+	(*cf)->len = CAN_ERR_DLC;
+
+	return skb;
+}
+EXPORT_SYMBOL_GPL(alloc_can_err_skb);
+
+/* Check for outgoing skbs that have not been created by the CAN subsystem */
+static bool can_skb_init_valid(struct net_device *dev, struct sk_buff *skb)
+{
+	struct can_skb_ext *csx = can_skb_ext_find(skb);
+
+	/* af_packet does not apply CAN skb specific settings */
+	if (skb->ip_summed == CHECKSUM_NONE || !csx) {
+		/* init CAN skb content */
+		if (!csx) {
+			csx = can_skb_ext_add(skb);
+			if (!csx)
+				return false;
+		}
+
+		csx->can_iif = dev->ifindex;
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+		/* perform proper loopback on capable devices */
+		if (dev->flags & IFF_ECHO)
+			skb->pkt_type = PACKET_LOOPBACK;
+		else
+			skb->pkt_type = PACKET_HOST;
+
+		skb_reset_mac_header(skb);
+		skb_reset_network_header(skb);
+		skb_reset_transport_header(skb);
+
+		/* set CANFD_FDF flag for CAN FD frames */
+		if (can_is_canfd_skb(skb)) {
+			struct canfd_frame *cfd;
+
+			cfd = (struct canfd_frame *)skb->data;
+			cfd->flags |= CANFD_FDF;
+		}
+	}
+
+	return true;
+}
+
+/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
+bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb)
+{
+	switch (ntohs(skb->protocol)) {
+	case ETH_P_CAN:
+		if (!can_is_can_skb(skb))
+			goto inval_skb;
+		break;
+
+	case ETH_P_CANFD:
+		if (!can_is_canfd_skb(skb))
+			goto inval_skb;
+		break;
+
+	case ETH_P_CANXL:
+		if (!can_is_canxl_skb(skb))
+			goto inval_skb;
+		break;
+
+	default:
+		goto inval_skb;
+	}
+
+	if (!can_skb_init_valid(dev, skb))
+		goto inval_skb;
+
+	return false;
+
+inval_skb:
+	kfree_skb(skb);
+	dev->stats.tx_dropped++;
+	return true;
+}
+EXPORT_SYMBOL_GPL(can_dropped_invalid_skb);