diff mbox series

[v9,4/7] can: Add Nuvoton NCT6694 CANFD support

Message ID 20250409082752.3697532-5-tmyu0@nuvoton.com
State New
Headers show
Series Add Nuvoton NCT6694 MFD drivers | expand

Commit Message

Ming Yu April 9, 2025, 8:27 a.m. UTC
From: Ming Yu <tmyu0@nuvoton.com>

This driver supports Socket CANFD functionality for NCT6694 MFD
device based on USB interface.

Signed-off-by: Ming Yu <tmyu0@nuvoton.com>
---
 MAINTAINERS                         |   1 +
 drivers/net/can/usb/Kconfig         |  11 +
 drivers/net/can/usb/Makefile        |   1 +
 drivers/net/can/usb/nct6694_canfd.c | 815 ++++++++++++++++++++++++++++
 4 files changed, 828 insertions(+)
 create mode 100644 drivers/net/can/usb/nct6694_canfd.c

Comments

Marc Kleine-Budde April 9, 2025, 10:21 a.m. UTC | #1
This looks really good now. Some questions and a nitpick inline.

On 09.04.2025 16:27:49, a0282524688@gmail.com wrote:

[...]

> +static void nct6694_canfd_handle_state_change(struct net_device *ndev, u8 status)
> +{
> +	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> +	enum can_state new_state, rx_state, tx_state;
> +	struct can_berr_counter bec;
> +	struct can_frame *cf;
> +	struct sk_buff *skb;
> +
> +	nct6694_canfd_get_berr_counter(ndev, &bec);
> +	can_state_get_by_berr_counter(ndev, &bec, &tx_state, &rx_state);
> +
> +	new_state = max(tx_state, rx_state);
> +
> +	/* state hasn't changed */
> +	if (new_state == priv->can.state)
> +		return;
> +
> +	skb = alloc_can_err_skb(ndev, &cf);
> +
> +	can_change_state(ndev, cf, tx_state, rx_state);
> +
> +	if (new_state == CAN_STATE_BUS_OFF) {
> +		can_bus_off(ndev);

What does your device do when it goes into bus off? Does it recover itself?

> +	} else if (cf) {
> +		cf->can_id |= CAN_ERR_CNT;
> +		cf->data[6] = bec.txerr;
> +		cf->data[7] = bec.rxerr;
> +	}
> +
> +	if (skb)
> +		nct6694_canfd_rx_offload(&priv->offload, skb);
> +}
> +
> +static void nct6694_canfd_handle_bus_err(struct net_device *ndev, u8 bus_err)
> +{
> +	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> +	struct can_frame *cf;
> +	struct sk_buff *skb;
> +
> +	if (bus_err == NCT6694_CANFD_EVT_ERR_NO_ERROR)
> +		return;

I think this has already been checked nct6694_canfd_irq()

> +
> +	priv->can.can_stats.bus_error++;
> +
> +	skb = alloc_can_err_skb(ndev, &cf);
> +	if (cf)
> +		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
> +
> +	switch (bus_err) {
> +	case NCT6694_CANFD_EVT_ERR_CRC_ERROR:
> +		netdev_dbg(ndev, "CRC error\n");
> +		ndev->stats.rx_errors++;
> +		if (cf)
> +			cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
> +		break;
> +
> +	case NCT6694_CANFD_EVT_ERR_STUFF_ERROR:
> +		netdev_dbg(ndev, "Stuff error\n");
> +		ndev->stats.rx_errors++;
> +		if (cf)
> +			cf->data[2] |= CAN_ERR_PROT_STUFF;
> +		break;
> +
> +	case NCT6694_CANFD_EVT_ERR_ACK_ERROR:
> +		netdev_dbg(ndev, "Ack error\n");
> +		ndev->stats.tx_errors++;
> +		if (cf) {
> +			cf->can_id |= CAN_ERR_ACK;
> +			cf->data[2] |= CAN_ERR_PROT_TX;
> +		}
> +		break;
> +
> +	case NCT6694_CANFD_EVT_ERR_FORM_ERROR:
> +		netdev_dbg(ndev, "Form error\n");
> +		ndev->stats.rx_errors++;
> +		if (cf)
> +			cf->data[2] |= CAN_ERR_PROT_FORM;
> +		break;
> +
> +	case NCT6694_CANFD_EVT_ERR_BIT_ERROR:
> +		netdev_dbg(ndev, "Bit error\n");
> +		ndev->stats.tx_errors++;
> +		if (cf)
> +			cf->data[2] |= CAN_ERR_PROT_TX | CAN_ERR_PROT_BIT;
> +		break;
> +
> +	default:
> +		break;
> +	}
> +
> +	if (skb)
> +		nct6694_canfd_rx_offload(&priv->offload, skb);
> +}

[...]

> +static int nct6694_canfd_start(struct net_device *ndev)
> +{
> +	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> +	const struct can_bittiming *d_bt = &priv->can.data_bittiming;
> +	const struct can_bittiming *n_bt = &priv->can.bittiming;
> +	struct nct6694_canfd_setting *setting __free(kfree) = NULL;
> +	const struct nct6694_cmd_header cmd_hd = {
> +		.mod = NCT6694_CANFD_MOD,
> +		.cmd = NCT6694_CANFD_SETTING,
> +		.sel = ndev->dev_port,
> +		.len = cpu_to_le16(sizeof(*setting))
> +	};
> +	int ret;
> +
> +	setting = kzalloc(sizeof(*setting), GFP_KERNEL);
> +	if (!setting)
> +		return -ENOMEM;
> +
> +	setting->nbr = cpu_to_le32(n_bt->bitrate);
> +	setting->dbr = cpu_to_le32(d_bt->bitrate);
> +
> +	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
> +		setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_MON);
> +
> +	if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
> +		setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_NISO);
> +
> +	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
> +		setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_LBCK);
> +
> +	setting->nbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NSJW,
> +					       n_bt->sjw - 1) |
> +				    FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NBRP,
> +					       n_bt->brp - 1) |
> +				    FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG2,
> +					       n_bt->phase_seg2 - 1) |
> +				    FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG1,
> +					       n_bt->prop_seg + n_bt->phase_seg1 - 1));
> +
> +	setting->dbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DSJW,
> +					       d_bt->sjw - 1) |
> +				    FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DBRP,
> +					       d_bt->brp - 1) |
> +				    FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG2,
> +					       d_bt->phase_seg2 - 1) |
> +				    FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG1,
> +					       d_bt->prop_seg + d_bt->phase_seg1 - 1));

What does your device do, if you set the bitrates _and_ the bit timing
parameters? They are redundant.

> +	setting->active = NCT6694_CANFD_SETTING_ACTIVE_CTRL1 |
> +			  NCT6694_CANFD_SETTING_ACTIVE_NBTP_DBTP;
> +
> +	ret = nct6694_write_msg(priv->nct6694, &cmd_hd, setting);
> +	if (ret)
> +		return ret;
> +
> +	priv->can.state = CAN_STATE_ERROR_ACTIVE;
> +
> +	return 0;
> +}

regards,
Marc
Ming Yu April 10, 2025, 2:40 a.m. UTC | #2
Dear Marc,

Thank you for reviewing.

Marc Kleine-Budde <mkl@pengutronix.de> 於 2025年4月9日 週三 下午6:21寫道:
...
> > +static void nct6694_canfd_handle_state_change(struct net_device *ndev, u8 status)
> > +{
> > +     struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> > +     enum can_state new_state, rx_state, tx_state;
> > +     struct can_berr_counter bec;
> > +     struct can_frame *cf;
> > +     struct sk_buff *skb;
> > +
> > +     nct6694_canfd_get_berr_counter(ndev, &bec);
> > +     can_state_get_by_berr_counter(ndev, &bec, &tx_state, &rx_state);
> > +
> > +     new_state = max(tx_state, rx_state);
> > +
> > +     /* state hasn't changed */
> > +     if (new_state == priv->can.state)
> > +             return;
> > +
> > +     skb = alloc_can_err_skb(ndev, &cf);
> > +
> > +     can_change_state(ndev, cf, tx_state, rx_state);
> > +
> > +     if (new_state == CAN_STATE_BUS_OFF) {
> > +             can_bus_off(ndev);
>
> What does your device do when it goes into bus off? Does it recover itself?
>

No, the device does not support automatic bus-off recovery. It
requires an explicit CAN Setting and Initialization(CMD0) command to
re-initialize the controller after entering bus-off state.

> > +     } else if (cf) {
> > +             cf->can_id |= CAN_ERR_CNT;
> > +             cf->data[6] = bec.txerr;
> > +             cf->data[7] = bec.rxerr;
> > +     }
> > +
> > +     if (skb)
> > +             nct6694_canfd_rx_offload(&priv->offload, skb);
> > +}
> > +
> > +static void nct6694_canfd_handle_bus_err(struct net_device *ndev, u8 bus_err)
> > +{
> > +     struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> > +     struct can_frame *cf;
> > +     struct sk_buff *skb;
> > +
> > +     if (bus_err == NCT6694_CANFD_EVT_ERR_NO_ERROR)
> > +             return;
>
> I think this has already been checked nct6694_canfd_irq()
>

Drop it in v10.

> > +
...
> > +static int nct6694_canfd_start(struct net_device *ndev)
> > +{
> > +     struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> > +     const struct can_bittiming *d_bt = &priv->can.data_bittiming;
> > +     const struct can_bittiming *n_bt = &priv->can.bittiming;
> > +     struct nct6694_canfd_setting *setting __free(kfree) = NULL;
> > +     const struct nct6694_cmd_header cmd_hd = {
> > +             .mod = NCT6694_CANFD_MOD,
> > +             .cmd = NCT6694_CANFD_SETTING,
> > +             .sel = ndev->dev_port,
> > +             .len = cpu_to_le16(sizeof(*setting))
> > +     };
> > +     int ret;
> > +
> > +     setting = kzalloc(sizeof(*setting), GFP_KERNEL);
> > +     if (!setting)
> > +             return -ENOMEM;
> > +
> > +     setting->nbr = cpu_to_le32(n_bt->bitrate);
> > +     setting->dbr = cpu_to_le32(d_bt->bitrate);
> > +
> > +     if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
> > +             setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_MON);
> > +
> > +     if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
> > +             setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_NISO);
> > +
> > +     if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
> > +             setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_LBCK);
> > +
> > +     setting->nbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NSJW,
> > +                                            n_bt->sjw - 1) |
> > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NBRP,
> > +                                            n_bt->brp - 1) |
> > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG2,
> > +                                            n_bt->phase_seg2 - 1) |
> > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG1,
> > +                                            n_bt->prop_seg + n_bt->phase_seg1 - 1));
> > +
> > +     setting->dbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DSJW,
> > +                                            d_bt->sjw - 1) |
> > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DBRP,
> > +                                            d_bt->brp - 1) |
> > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG2,
> > +                                            d_bt->phase_seg2 - 1) |
> > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG1,
> > +                                            d_bt->prop_seg + d_bt->phase_seg1 - 1));
>
> What does your device do, if you set the bitrates _and_ the bit timing
> parameters? They are redundant.
>

The firmware calculates the default bit timing parameters when it
receives the bitrates, and then overwrites them if it later receives
explicit bit timing parameters.

To avoid confusion and ensure consistent behavior, I will remove the
bitrate setting logic in next patch. Instead, the bit timing will be
determined solely based on the provided bit timing parameters.

> > +     setting->active = NCT6694_CANFD_SETTING_ACTIVE_CTRL1 |
> > +                       NCT6694_CANFD_SETTING_ACTIVE_NBTP_DBTP;
> > +
> > +     ret = nct6694_write_msg(priv->nct6694, &cmd_hd, setting);
> > +     if (ret)
> > +             return ret;
> > +
> > +     priv->can.state = CAN_STATE_ERROR_ACTIVE;
> > +
> > +     return 0;
> > +}
>

Best regards,
Ming
Marc Kleine-Budde April 10, 2025, 6:04 a.m. UTC | #3
On 10.04.2025 10:40:34, Ming Yu wrote:
> Dear Marc,
> 
> Thank you for reviewing.
> 
> Marc Kleine-Budde <mkl@pengutronix.de> 於 2025年4月9日 週三 下午6:21寫道:
> ...
> > > +static void nct6694_canfd_handle_state_change(struct net_device *ndev, u8 status)
> > > +{
> > > +     struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> > > +     enum can_state new_state, rx_state, tx_state;
> > > +     struct can_berr_counter bec;
> > > +     struct can_frame *cf;
> > > +     struct sk_buff *skb;
> > > +
> > > +     nct6694_canfd_get_berr_counter(ndev, &bec);
> > > +     can_state_get_by_berr_counter(ndev, &bec, &tx_state, &rx_state);
> > > +
> > > +     new_state = max(tx_state, rx_state);
> > > +
> > > +     /* state hasn't changed */
> > > +     if (new_state == priv->can.state)
> > > +             return;
> > > +
> > > +     skb = alloc_can_err_skb(ndev, &cf);
> > > +
> > > +     can_change_state(ndev, cf, tx_state, rx_state);
> > > +
> > > +     if (new_state == CAN_STATE_BUS_OFF) {
> > > +             can_bus_off(ndev);
> >
> > What does your device do when it goes into bus off? Does it recover itself?
> >
> 
> No, the device does not support automatic bus-off recovery. It
> requires an explicit CAN Setting and Initialization(CMD0) command to
> re-initialize the controller after entering bus-off state.

Ok

[...]

> > > +static int nct6694_canfd_start(struct net_device *ndev)
> > > +{
> > > +     struct nct6694_canfd_priv *priv = netdev_priv(ndev);
> > > +     const struct can_bittiming *d_bt = &priv->can.data_bittiming;
> > > +     const struct can_bittiming *n_bt = &priv->can.bittiming;
> > > +     struct nct6694_canfd_setting *setting __free(kfree) = NULL;
> > > +     const struct nct6694_cmd_header cmd_hd = {
> > > +             .mod = NCT6694_CANFD_MOD,
> > > +             .cmd = NCT6694_CANFD_SETTING,
> > > +             .sel = ndev->dev_port,
> > > +             .len = cpu_to_le16(sizeof(*setting))
> > > +     };
> > > +     int ret;
> > > +
> > > +     setting = kzalloc(sizeof(*setting), GFP_KERNEL);
> > > +     if (!setting)
> > > +             return -ENOMEM;
> > > +
> > > +     setting->nbr = cpu_to_le32(n_bt->bitrate);
> > > +     setting->dbr = cpu_to_le32(d_bt->bitrate);
> > > +
> > > +     if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
> > > +             setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_MON);
> > > +
> > > +     if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
> > > +             setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_NISO);
> > > +
> > > +     if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
> > > +             setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_LBCK);
> > > +
> > > +     setting->nbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NSJW,
> > > +                                            n_bt->sjw - 1) |
> > > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NBRP,
> > > +                                            n_bt->brp - 1) |
> > > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG2,
> > > +                                            n_bt->phase_seg2 - 1) |
> > > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG1,
> > > +                                            n_bt->prop_seg + n_bt->phase_seg1 - 1));
> > > +
> > > +     setting->dbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DSJW,
> > > +                                            d_bt->sjw - 1) |
> > > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DBRP,
> > > +                                            d_bt->brp - 1) |
> > > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG2,
> > > +                                            d_bt->phase_seg2 - 1) |
> > > +                                 FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG1,
> > > +                                            d_bt->prop_seg + d_bt->phase_seg1 - 1));
> >
> > What does your device do, if you set the bitrates _and_ the bit timing
> > parameters? They are redundant.
> 
> The firmware calculates the default bit timing parameters when it
> receives the bitrates, and then overwrites them if it later receives
> explicit bit timing parameters.
> 
> To avoid confusion and ensure consistent behavior, I will remove the
> bitrate setting logic in next patch. Instead, the bit timing will be
> determined solely based on the provided bit timing parameters.

Sounds good.

regards,
Marc
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index c2d7be0cdb58..3a96a8730e6d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17308,6 +17308,7 @@  S:	Supported
 F:	drivers/gpio/gpio-nct6694.c
 F:	drivers/i2c/busses/i2c-nct6694.c
 F:	drivers/mfd/nct6694.c
+F:	drivers/net/can/usb/nct6694_canfd.c
 F:	include/linux/mfd/nct6694.h
 
 NVIDIA (rivafb and nvidiafb) FRAMEBUFFER DRIVER
diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig
index 9dae0c71a2e1..759e724a67cf 100644
--- a/drivers/net/can/usb/Kconfig
+++ b/drivers/net/can/usb/Kconfig
@@ -133,6 +133,17 @@  config CAN_MCBA_USB
 	  This driver supports the CAN BUS Analyzer interface
 	  from Microchip (http://www.microchip.com/development-tools/).
 
+config CAN_NCT6694
+	tristate "Nuvoton NCT6694 Socket CANfd support"
+	depends on MFD_NCT6694
+	select CAN_RX_OFFLOAD
+	help
+	  If you say yes to this option, support will be included for Nuvoton
+	  NCT6694, a USB device to socket CANfd controller.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called nct6694_canfd.
+
 config CAN_PEAK_USB
 	tristate "PEAK PCAN-USB/USB Pro interfaces for CAN 2.0b/CAN-FD"
 	help
diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile
index 8b11088e9a59..fcafb1ac262e 100644
--- a/drivers/net/can/usb/Makefile
+++ b/drivers/net/can/usb/Makefile
@@ -11,5 +11,6 @@  obj-$(CONFIG_CAN_F81604) += f81604.o
 obj-$(CONFIG_CAN_GS_USB) += gs_usb.o
 obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb/
 obj-$(CONFIG_CAN_MCBA_USB) += mcba_usb.o
+obj-$(CONFIG_CAN_NCT6694) += nct6694_canfd.o
 obj-$(CONFIG_CAN_PEAK_USB) += peak_usb/
 obj-$(CONFIG_CAN_UCAN) += ucan.o
diff --git a/drivers/net/can/usb/nct6694_canfd.c b/drivers/net/can/usb/nct6694_canfd.c
new file mode 100644
index 000000000000..76ffc23e8184
--- /dev/null
+++ b/drivers/net/can/usb/nct6694_canfd.c
@@ -0,0 +1,815 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Nuvoton NCT6694 Socket CANfd driver based on USB interface.
+ *
+ * Copyright (C) 2024 Nuvoton Technology Corp.
+ */
+
+#include <linux/can/dev.h>
+#include <linux/can/rx-offload.h>
+#include <linux/ethtool.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/nct6694.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/platform_device.h>
+
+#define DEVICE_NAME "nct6694-canfd"
+
+/* USB command module type for NCT6694 CANfd controller.
+ * This defines the module type used for communication with the NCT6694
+ * CANfd controller over the USB interface.
+ */
+#define NCT6694_CANFD_MOD			0x05
+
+/* Command 00h - CAN Setting and Initialization */
+#define NCT6694_CANFD_SETTING			0x00
+#define NCT6694_CANFD_SETTING_ACTIVE_CTRL1	BIT(0)
+#define NCT6694_CANFD_SETTING_ACTIVE_NBTP_DBTP	BIT(2)
+#define NCT6694_CANFD_SETTING_CTRL1_MON		BIT(0)
+#define NCT6694_CANFD_SETTING_CTRL1_NISO	BIT(1)
+#define NCT6694_CANFD_SETTING_CTRL1_LBCK	BIT(2)
+#define NCT6694_CANFD_SETTING_NBTP_NTSEG2	GENMASK(6, 0)
+#define NCT6694_CANFD_SETTING_NBTP_NTSEG1	GENMASK(15, 8)
+#define NCT6694_CANFD_SETTING_NBTP_NBRP		GENMASK(24, 16)
+#define NCT6694_CANFD_SETTING_NBTP_NSJW		GENMASK(31, 25)
+#define NCT6694_CANFD_SETTING_DBTP_DSJW		GENMASK(3, 0)
+#define NCT6694_CANFD_SETTING_DBTP_DTSEG2	GENMASK(7, 4)
+#define NCT6694_CANFD_SETTING_DBTP_DTSEG1	GENMASK(12, 8)
+#define NCT6694_CANFD_SETTING_DBTP_DBRP		GENMASK(20, 16)
+
+/* Command 01h - CAN Information */
+#define NCT6694_CANFD_INFORMATION		0x01
+#define NCT6694_CANFD_INFORMATION_SEL		0x00
+
+/* Command 02h - CAN Event */
+#define NCT6694_CANFD_EVENT			0x02
+#define NCT6694_CANFD_EVENT_SEL(idx, mask)	\
+	((idx ? 0x80 : 0x00) | ((mask) & 0x7F))
+
+#define NCT6694_CANFD_EVENT_MASK		GENMASK(5, 0)
+#define NCT6694_CANFD_EVT_TX_FIFO_EMPTY		BIT(7)	/* Read-clear */
+#define NCT6694_CANFD_EVT_RX_DATA_LOST		BIT(5)	/* Read-clear */
+#define NCT6694_CANFD_EVT_RX_DATA_IN		BIT(7)	/* Read-clear*/
+
+/* Command 10h - CAN Deliver */
+#define NCT6694_CANFD_DELIVER			0x10
+#define NCT6694_CANFD_DELIVER_SEL(buf_cnt)	\
+	((buf_cnt) & 0xFF)
+
+/* Command 11h - CAN Receive */
+#define NCT6694_CANFD_RECEIVE			0x11
+#define NCT6694_CANFD_RECEIVE_SEL(idx, buf_cnt)	\
+	((idx ? 0x80 : 0x00) | ((buf_cnt) & 0x7F))
+
+#define NCT6694_CANFD_FRAME_TAG(idx)		(0xC0 | (idx))
+#define NCT6694_CANFD_FRAME_FLAG_EFF		BIT(0)
+#define NCT6694_CANFD_FRAME_FLAG_RTR		BIT(1)
+#define NCT6694_CANFD_FRAME_FLAG_FD		BIT(2)
+#define NCT6694_CANFD_FRAME_FLAG_BRS		BIT(3)
+#define NCT6694_CANFD_FRAME_FLAG_ERR		BIT(4)
+
+#define NCT6694_NAPI_WEIGHT			32
+
+enum nct6694_event_err {
+	NCT6694_CANFD_EVT_ERR_NO_ERROR = 0,
+	NCT6694_CANFD_EVT_ERR_CRC_ERROR,
+	NCT6694_CANFD_EVT_ERR_STUFF_ERROR,
+	NCT6694_CANFD_EVT_ERR_ACK_ERROR,
+	NCT6694_CANFD_EVT_ERR_FORM_ERROR,
+	NCT6694_CANFD_EVT_ERR_BIT_ERROR,
+	NCT6694_CANFD_EVT_ERR_TIMEOUT_ERROR,
+	NCT6694_CANFD_EVT_ERR_UNKNOWN_ERROR,
+};
+
+enum nct6694_event_status {
+	NCT6694_CANFD_EVT_STS_ERROR_ACTIVE = 0,
+	NCT6694_CANFD_EVT_STS_ERROR_PASSIVE,
+	NCT6694_CANFD_EVT_STS_BUS_OFF,
+	NCT6694_CANFD_EVT_STS_WARNING,
+};
+
+struct __packed nct6694_canfd_setting {
+	__le32 nbr;
+	__le32 dbr;
+	u8 active;
+	u8 reserved[3];
+	__le16 ctrl1;
+	__le16 ctrl2;
+	__le32 nbtp;
+	__le32 dbtp;
+};
+
+struct __packed nct6694_canfd_information {
+	u8 tx_fifo_cnt;
+	u8 rx_fifo_cnt;
+	u8 reserved[2];
+	__le32 can_clk;
+};
+
+struct __packed nct6694_canfd_event {
+	u8 err;
+	u8 status;
+	u8 tx_evt;
+	u8 rx_evt;
+	u8 rec;
+	u8 tec;
+	u8 reserved[2];
+};
+
+struct __packed nct6694_canfd_frame {
+	u8 tag;
+	u8 flag;
+	u8 reserved;
+	u8 length;
+	__le32 id;
+	u8 data[CANFD_MAX_DLEN];
+};
+
+struct nct6694_canfd_priv {
+	struct can_priv can;	/* must be the first member */
+	struct can_rx_offload offload;
+	struct net_device *ndev;
+	struct nct6694 *nct6694;
+	struct workqueue_struct *wq;
+	struct work_struct tx_work;
+	struct nct6694_canfd_frame tx;
+	struct nct6694_canfd_frame rx;
+	struct nct6694_canfd_event event[2];
+	struct can_berr_counter bec;
+};
+
+static inline struct nct6694_canfd_priv *rx_offload_to_priv(struct can_rx_offload *offload)
+{
+	return container_of(offload, struct nct6694_canfd_priv, offload);
+}
+
+static const struct can_bittiming_const nct6694_canfd_bittiming_nominal_const = {
+	.name = DEVICE_NAME,
+	.tseg1_min = 1,
+	.tseg1_max = 256,
+	.tseg2_min = 1,
+	.tseg2_max = 128,
+	.sjw_max = 128,
+	.brp_min = 1,
+	.brp_max = 512,
+	.brp_inc = 1,
+};
+
+static const struct can_bittiming_const nct6694_canfd_bittiming_data_const = {
+	.name = DEVICE_NAME,
+	.tseg1_min = 1,
+	.tseg1_max = 32,
+	.tseg2_min = 1,
+	.tseg2_max = 16,
+	.sjw_max = 16,
+	.brp_min = 1,
+	.brp_max = 32,
+	.brp_inc = 1,
+};
+
+static void nct6694_canfd_rx_offload(struct can_rx_offload *offload,
+				     struct sk_buff *skb)
+{
+	struct nct6694_canfd_priv *priv = rx_offload_to_priv(offload);
+	int ret;
+
+	ret = can_rx_offload_queue_tail(offload, skb);
+	if (ret)
+		priv->ndev->stats.rx_fifo_errors++;
+}
+
+static void nct6694_canfd_handle_lost_msg(struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	netdev_dbg(ndev, "RX FIFO overflow, message(s) lost.\n");
+
+	stats->rx_errors++;
+	stats->rx_over_errors++;
+
+	skb = alloc_can_err_skb(ndev, &cf);
+	if (!skb)
+		return;
+
+	cf->can_id |= CAN_ERR_CRTL;
+	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+
+	nct6694_canfd_rx_offload(&priv->offload, skb);
+}
+
+static void nct6694_canfd_handle_rx(struct net_device *ndev, u8 rx_evt)
+{
+	struct net_device_stats *stats = &ndev->stats;
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	struct nct6694_canfd_frame *frame = &priv->rx;
+	const struct nct6694_cmd_header cmd_hd = {
+		.mod = NCT6694_CANFD_MOD,
+		.cmd = NCT6694_CANFD_RECEIVE,
+		.sel = NCT6694_CANFD_RECEIVE_SEL(ndev->dev_port, 1),
+		.len = cpu_to_le16(sizeof(*frame))
+	};
+	struct sk_buff *skb;
+	int ret;
+
+	ret = nct6694_read_msg(priv->nct6694, &cmd_hd, frame);
+	if (ret)
+		return;
+
+	if (frame->flag & NCT6694_CANFD_FRAME_FLAG_FD) {
+		struct canfd_frame *cfd;
+
+		skb = alloc_canfd_skb(priv->ndev, &cfd);
+		if (!skb) {
+			stats->rx_dropped++;
+			return;
+		}
+
+		cfd->can_id = le32_to_cpu(frame->id);
+		cfd->len = canfd_sanitize_len(frame->length);
+		if (frame->flag & NCT6694_CANFD_FRAME_FLAG_EFF)
+			cfd->can_id |= CAN_EFF_FLAG;
+		if (frame->flag & NCT6694_CANFD_FRAME_FLAG_BRS)
+			cfd->flags |= CANFD_BRS;
+		if (frame->flag & NCT6694_CANFD_FRAME_FLAG_ERR)
+			cfd->flags |= CANFD_ESI;
+
+		memcpy(cfd->data, frame->data, cfd->len);
+	} else {
+		struct can_frame *cf;
+
+		skb = alloc_can_skb(priv->ndev, &cf);
+		if (!skb) {
+			stats->rx_dropped++;
+			return;
+		}
+
+		cf->can_id = le32_to_cpu(frame->id);
+		cf->len = can_cc_dlc2len(frame->length);
+		if (frame->flag & NCT6694_CANFD_FRAME_FLAG_EFF)
+			cf->can_id |= CAN_EFF_FLAG;
+
+		if (frame->flag & NCT6694_CANFD_FRAME_FLAG_RTR)
+			cf->can_id |= CAN_RTR_FLAG;
+		else
+			memcpy(cf->data, frame->data, cf->len);
+	}
+
+	nct6694_canfd_rx_offload(&priv->offload, skb);
+}
+
+static int nct6694_canfd_get_berr_counter(const struct net_device *ndev,
+					  struct can_berr_counter *bec)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+
+	*bec = priv->bec;
+
+	return 0;
+}
+
+static void nct6694_canfd_handle_state_change(struct net_device *ndev, u8 status)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	enum can_state new_state, rx_state, tx_state;
+	struct can_berr_counter bec;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	nct6694_canfd_get_berr_counter(ndev, &bec);
+	can_state_get_by_berr_counter(ndev, &bec, &tx_state, &rx_state);
+
+	new_state = max(tx_state, rx_state);
+
+	/* state hasn't changed */
+	if (new_state == priv->can.state)
+		return;
+
+	skb = alloc_can_err_skb(ndev, &cf);
+
+	can_change_state(ndev, cf, tx_state, rx_state);
+
+	if (new_state == CAN_STATE_BUS_OFF) {
+		can_bus_off(ndev);
+	} else if (cf) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = bec.txerr;
+		cf->data[7] = bec.rxerr;
+	}
+
+	if (skb)
+		nct6694_canfd_rx_offload(&priv->offload, skb);
+}
+
+static void nct6694_canfd_handle_bus_err(struct net_device *ndev, u8 bus_err)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	if (bus_err == NCT6694_CANFD_EVT_ERR_NO_ERROR)
+		return;
+
+	priv->can.can_stats.bus_error++;
+
+	skb = alloc_can_err_skb(ndev, &cf);
+	if (cf)
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+	switch (bus_err) {
+	case NCT6694_CANFD_EVT_ERR_CRC_ERROR:
+		netdev_dbg(ndev, "CRC error\n");
+		ndev->stats.rx_errors++;
+		if (cf)
+			cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
+		break;
+
+	case NCT6694_CANFD_EVT_ERR_STUFF_ERROR:
+		netdev_dbg(ndev, "Stuff error\n");
+		ndev->stats.rx_errors++;
+		if (cf)
+			cf->data[2] |= CAN_ERR_PROT_STUFF;
+		break;
+
+	case NCT6694_CANFD_EVT_ERR_ACK_ERROR:
+		netdev_dbg(ndev, "Ack error\n");
+		ndev->stats.tx_errors++;
+		if (cf) {
+			cf->can_id |= CAN_ERR_ACK;
+			cf->data[2] |= CAN_ERR_PROT_TX;
+		}
+		break;
+
+	case NCT6694_CANFD_EVT_ERR_FORM_ERROR:
+		netdev_dbg(ndev, "Form error\n");
+		ndev->stats.rx_errors++;
+		if (cf)
+			cf->data[2] |= CAN_ERR_PROT_FORM;
+		break;
+
+	case NCT6694_CANFD_EVT_ERR_BIT_ERROR:
+		netdev_dbg(ndev, "Bit error\n");
+		ndev->stats.tx_errors++;
+		if (cf)
+			cf->data[2] |= CAN_ERR_PROT_TX | CAN_ERR_PROT_BIT;
+		break;
+
+	default:
+		break;
+	}
+
+	if (skb)
+		nct6694_canfd_rx_offload(&priv->offload, skb);
+}
+
+static void nct6694_canfd_handle_tx(struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &ndev->stats;
+
+	stats->tx_bytes += can_rx_offload_get_echo_skb_queue_tail(&priv->offload,
+								  0, NULL);
+	stats->tx_packets++;
+	netif_wake_queue(ndev);
+}
+
+static irqreturn_t nct6694_canfd_irq(int irq, void *data)
+{
+	struct net_device *ndev = data;
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	struct nct6694_canfd_event *event = &priv->event[ndev->dev_port];
+	const struct nct6694_cmd_header cmd_hd = {
+		.mod = NCT6694_CANFD_MOD,
+		.cmd = NCT6694_CANFD_EVENT,
+		.sel = NCT6694_CANFD_EVENT_SEL(ndev->dev_port, NCT6694_CANFD_EVENT_MASK),
+		.len = cpu_to_le16(sizeof(priv->event))
+	};
+	irqreturn_t handled = IRQ_NONE;
+	int ret;
+
+	ret = nct6694_read_msg(priv->nct6694, &cmd_hd, priv->event);
+	if (ret < 0)
+		return handled;
+
+	if (event->rx_evt & NCT6694_CANFD_EVT_RX_DATA_IN) {
+		nct6694_canfd_handle_rx(ndev, event->rx_evt);
+		handled = IRQ_HANDLED;
+	}
+
+	if (event->rx_evt & NCT6694_CANFD_EVT_RX_DATA_LOST) {
+		nct6694_canfd_handle_lost_msg(ndev);
+		handled = IRQ_HANDLED;
+	}
+
+	if (event->status) {
+		nct6694_canfd_handle_state_change(ndev, event->status);
+		handled = IRQ_HANDLED;
+	}
+
+	if (event->err != NCT6694_CANFD_EVT_ERR_NO_ERROR) {
+		if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+			nct6694_canfd_handle_bus_err(ndev, event->err);
+		handled = IRQ_HANDLED;
+	}
+
+	if (event->tx_evt & NCT6694_CANFD_EVT_TX_FIFO_EMPTY) {
+		nct6694_canfd_handle_tx(ndev);
+		handled = IRQ_HANDLED;
+	}
+
+	if (handled)
+		can_rx_offload_threaded_irq_finish(&priv->offload);
+
+	priv->bec.rxerr = event->rec;
+	priv->bec.txerr = event->tec;
+
+	return handled;
+}
+
+static void nct6694_canfd_tx_work(struct work_struct *work)
+{
+	struct nct6694_canfd_priv *priv = container_of(work,
+						       struct nct6694_canfd_priv,
+						       tx_work);
+	struct nct6694_canfd_frame *frame = &priv->tx;
+	struct net_device *ndev = priv->ndev;
+	struct net_device_stats *stats = &ndev->stats;
+	struct sk_buff *skb = priv->can.echo_skb[0];
+	static const struct nct6694_cmd_header cmd_hd = {
+		.mod = NCT6694_CANFD_MOD,
+		.cmd = NCT6694_CANFD_DELIVER,
+		.sel = NCT6694_CANFD_DELIVER_SEL(1),
+		.len = cpu_to_le16(sizeof(*frame))
+	};
+	u32 txid;
+	int err;
+
+	memset(frame, 0, sizeof(*frame));
+
+	frame->tag = NCT6694_CANFD_FRAME_TAG(ndev->dev_port);
+
+	if (can_is_canfd_skb(skb)) {
+		struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+		if (cfd->flags & CANFD_BRS)
+			frame->flag |= NCT6694_CANFD_FRAME_FLAG_BRS;
+
+		if (cfd->can_id & CAN_EFF_FLAG) {
+			txid = cfd->can_id & CAN_EFF_MASK;
+			frame->flag |= NCT6694_CANFD_FRAME_FLAG_EFF;
+		} else {
+			txid = cfd->can_id & CAN_SFF_MASK;
+		}
+		frame->flag |= NCT6694_CANFD_FRAME_FLAG_FD;
+		frame->id = cpu_to_le32(txid);
+		frame->length = canfd_sanitize_len(cfd->len);
+
+		memcpy(frame->data, cfd->data, frame->length);
+	} else {
+		struct can_frame *cf = (struct can_frame *)skb->data;
+
+		if (cf->can_id & CAN_EFF_FLAG) {
+			txid = cf->can_id & CAN_EFF_MASK;
+			frame->flag |= NCT6694_CANFD_FRAME_FLAG_EFF;
+		} else {
+			txid = cf->can_id & CAN_SFF_MASK;
+		}
+
+		if (cf->can_id & CAN_RTR_FLAG)
+			frame->flag |= NCT6694_CANFD_FRAME_FLAG_RTR;
+		else
+			memcpy(frame->data, cf->data, cf->len);
+
+		frame->id = cpu_to_le32(txid);
+		frame->length = cf->len;
+	}
+
+	err = nct6694_write_msg(priv->nct6694, &cmd_hd, frame);
+	if (err) {
+		can_free_echo_skb(ndev, 0, NULL);
+		stats->tx_dropped++;
+		stats->tx_errors++;
+		netif_wake_queue(ndev);
+	}
+}
+
+static netdev_tx_t nct6694_canfd_start_xmit(struct sk_buff *skb,
+					    struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+
+	if (can_dev_dropped_skb(ndev, skb))
+		return NETDEV_TX_OK;
+
+	netif_stop_queue(ndev);
+	can_put_echo_skb(skb, ndev, 0, 0);
+	queue_work(priv->wq, &priv->tx_work);
+
+	return NETDEV_TX_OK;
+}
+
+static int nct6694_canfd_start(struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	const struct can_bittiming *d_bt = &priv->can.data_bittiming;
+	const struct can_bittiming *n_bt = &priv->can.bittiming;
+	struct nct6694_canfd_setting *setting __free(kfree) = NULL;
+	const struct nct6694_cmd_header cmd_hd = {
+		.mod = NCT6694_CANFD_MOD,
+		.cmd = NCT6694_CANFD_SETTING,
+		.sel = ndev->dev_port,
+		.len = cpu_to_le16(sizeof(*setting))
+	};
+	int ret;
+
+	setting = kzalloc(sizeof(*setting), GFP_KERNEL);
+	if (!setting)
+		return -ENOMEM;
+
+	setting->nbr = cpu_to_le32(n_bt->bitrate);
+	setting->dbr = cpu_to_le32(d_bt->bitrate);
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+		setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_MON);
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
+		setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_NISO);
+
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
+		setting->ctrl1 |= cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_LBCK);
+
+	setting->nbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NSJW,
+					       n_bt->sjw - 1) |
+				    FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NBRP,
+					       n_bt->brp - 1) |
+				    FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG2,
+					       n_bt->phase_seg2 - 1) |
+				    FIELD_PREP(NCT6694_CANFD_SETTING_NBTP_NTSEG1,
+					       n_bt->prop_seg + n_bt->phase_seg1 - 1));
+
+	setting->dbtp = cpu_to_le32(FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DSJW,
+					       d_bt->sjw - 1) |
+				    FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DBRP,
+					       d_bt->brp - 1) |
+				    FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG2,
+					       d_bt->phase_seg2 - 1) |
+				    FIELD_PREP(NCT6694_CANFD_SETTING_DBTP_DTSEG1,
+					       d_bt->prop_seg + d_bt->phase_seg1 - 1));
+
+	setting->active = NCT6694_CANFD_SETTING_ACTIVE_CTRL1 |
+			  NCT6694_CANFD_SETTING_ACTIVE_NBTP_DBTP;
+
+	ret = nct6694_write_msg(priv->nct6694, &cmd_hd, setting);
+	if (ret)
+		return ret;
+
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	return 0;
+}
+
+static void nct6694_canfd_stop(struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	struct nct6694_canfd_setting *setting __free(kfree) = NULL;
+	const struct nct6694_cmd_header cmd_hd = {
+		.mod = NCT6694_CANFD_MOD,
+		.cmd = NCT6694_CANFD_SETTING,
+		.sel = ndev->dev_port,
+		.len = cpu_to_le16(sizeof(*setting))
+	};
+
+	/* The NCT6694 cannot be stopped. To ensure safe operation and avoid
+	 * interference, the control mode is set to Listen-Only mode. This
+	 * mode allows the device to monitor bus activity without actively
+	 * participating in communication.
+	 */
+	setting = kzalloc(sizeof(*setting), GFP_KERNEL);
+	if (!setting)
+		return;
+
+	nct6694_read_msg(priv->nct6694, &cmd_hd, setting);
+	setting->ctrl1 = cpu_to_le16(NCT6694_CANFD_SETTING_CTRL1_MON);
+	setting->active = NCT6694_CANFD_SETTING_ACTIVE_CTRL1;
+	nct6694_write_msg(priv->nct6694, &cmd_hd, setting);
+
+	priv->can.state = CAN_STATE_STOPPED;
+}
+
+static int nct6694_canfd_close(struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+
+	netif_stop_queue(ndev);
+	can_rx_offload_disable(&priv->offload);
+	nct6694_canfd_stop(ndev);
+	free_irq(ndev->irq, ndev);
+	destroy_workqueue(priv->wq);
+	close_candev(ndev);
+	return 0;
+}
+
+static int nct6694_canfd_set_mode(struct net_device *ndev, enum can_mode mode)
+{
+	int ret;
+
+	switch (mode) {
+	case CAN_MODE_START:
+		ret = nct6694_canfd_start(ndev);
+		if (ret)
+			return ret;
+
+		netif_wake_queue(ndev);
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return ret;
+}
+
+static int nct6694_canfd_open(struct net_device *ndev)
+{
+	struct nct6694_canfd_priv *priv = netdev_priv(ndev);
+	int ret;
+
+	ret = open_candev(ndev);
+	if (ret)
+		return ret;
+
+	can_rx_offload_enable(&priv->offload);
+
+	ret = request_threaded_irq(ndev->irq, NULL,
+				   nct6694_canfd_irq, IRQF_ONESHOT,
+				   "nct6694_canfd", ndev);
+	if (ret) {
+		netdev_err(ndev, "Failed to request IRQ\n");
+		goto close_candev;
+	}
+
+	priv->wq = alloc_ordered_workqueue("%s-nct6694_wq",
+					   WQ_FREEZABLE | WQ_MEM_RECLAIM,
+					   ndev->name);
+	if (!priv->wq) {
+		ret = -ENOMEM;
+		goto free_irq;
+	}
+
+	ret = nct6694_canfd_start(ndev);
+	if (ret)
+		goto destroy_wq;
+
+	netif_start_queue(ndev);
+
+	return 0;
+
+destroy_wq:
+	destroy_workqueue(priv->wq);
+free_irq:
+	free_irq(ndev->irq, ndev);
+close_candev:
+	can_rx_offload_disable(&priv->offload);
+	close_candev(ndev);
+	return ret;
+}
+
+static const struct net_device_ops nct6694_canfd_netdev_ops = {
+	.ndo_open = nct6694_canfd_open,
+	.ndo_stop = nct6694_canfd_close,
+	.ndo_start_xmit = nct6694_canfd_start_xmit,
+	.ndo_change_mtu = can_change_mtu,
+};
+
+static const struct ethtool_ops nct6694_canfd_ethtool_ops = {
+	.get_ts_info = ethtool_op_get_ts_info,
+};
+
+static int nct6694_canfd_get_clock(struct nct6694_canfd_priv *priv)
+{
+	struct nct6694_canfd_information *info __free(kfree) = NULL;
+	static const struct nct6694_cmd_header cmd_hd = {
+		.mod = NCT6694_CANFD_MOD,
+		.cmd = NCT6694_CANFD_INFORMATION,
+		.sel = NCT6694_CANFD_INFORMATION_SEL,
+		.len = cpu_to_le16(sizeof(*info))
+	};
+	int ret, can_clk;
+
+	info = kzalloc(sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	ret = nct6694_read_msg(priv->nct6694, &cmd_hd, info);
+	if (ret)
+		return ret;
+
+	can_clk = le32_to_cpu(info->can_clk);
+
+	return can_clk;
+}
+
+static int nct6694_canfd_probe(struct platform_device *pdev)
+{
+	const struct mfd_cell *cell = mfd_get_cell(pdev);
+	struct nct6694 *nct6694 = dev_get_drvdata(pdev->dev.parent);
+	struct nct6694_canfd_priv *priv;
+	struct net_device *ndev;
+	int ret, irq, can_clk;
+
+	irq = irq_create_mapping(nct6694->domain,
+				 NCT6694_IRQ_CAN0 + cell->id);
+	if (!irq)
+		return irq;
+
+	ndev = alloc_candev(sizeof(struct nct6694_canfd_priv), 1);
+	if (!ndev) {
+		ret = -ENOMEM;
+		goto dispose_irq;
+	}
+
+	ndev->irq = irq;
+	ndev->flags |= IFF_ECHO;
+	ndev->dev_port = cell->id;
+	ndev->netdev_ops = &nct6694_canfd_netdev_ops;
+	ndev->ethtool_ops = &nct6694_canfd_ethtool_ops;
+
+	priv = netdev_priv(ndev);
+	priv->nct6694 = nct6694;
+	priv->ndev = ndev;
+
+	can_clk = nct6694_canfd_get_clock(priv);
+	if (can_clk < 0) {
+		ret = dev_err_probe(&pdev->dev, can_clk,
+				    "Failed to get clock\n");
+		goto free_candev;
+	}
+
+	INIT_WORK(&priv->tx_work, nct6694_canfd_tx_work);
+
+	priv->can.clock.freq = can_clk;
+	priv->can.bittiming_const = &nct6694_canfd_bittiming_nominal_const;
+	priv->can.data_bittiming_const = &nct6694_canfd_bittiming_data_const;
+	priv->can.do_set_mode = nct6694_canfd_set_mode;
+	priv->can.do_get_berr_counter = nct6694_canfd_get_berr_counter;
+	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
+		CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_BERR_REPORTING |
+		CAN_CTRLMODE_FD_NON_ISO;
+
+	ret = can_set_static_ctrlmode(ndev, CAN_CTRLMODE_FD);
+	if (ret)
+		goto free_candev;
+
+	ret = can_rx_offload_add_manual(ndev, &priv->offload,
+					NCT6694_NAPI_WEIGHT);
+	if (ret) {
+		dev_err_probe(&pdev->dev, ret, "Failed to add rx_offload\n");
+		goto free_candev;
+	}
+
+	platform_set_drvdata(pdev, priv);
+	SET_NETDEV_DEV(priv->ndev, &pdev->dev);
+
+	ret = register_candev(priv->ndev);
+	if (ret)
+		goto rx_offload_del;
+
+	return 0;
+
+rx_offload_del:
+	can_rx_offload_del(&priv->offload);
+free_candev:
+	free_candev(ndev);
+dispose_irq:
+	irq_dispose_mapping(irq);
+	return ret;
+}
+
+static void nct6694_canfd_remove(struct platform_device *pdev)
+{
+	struct nct6694_canfd_priv *priv = platform_get_drvdata(pdev);
+	struct net_device *ndev = priv->ndev;
+
+	unregister_candev(ndev);
+	irq_dispose_mapping(ndev->irq);
+	can_rx_offload_del(&priv->offload);
+	free_candev(ndev);
+}
+
+static struct platform_driver nct6694_canfd_driver = {
+	.driver = {
+		.name	= DEVICE_NAME,
+	},
+	.probe		= nct6694_canfd_probe,
+	.remove		= nct6694_canfd_remove,
+};
+
+module_platform_driver(nct6694_canfd_driver);
+
+MODULE_DESCRIPTION("USB-CAN FD driver for NCT6694");
+MODULE_AUTHOR("Ming Yu <tmyu0@nuvoton.com>");
+MODULE_LICENSE("GPL");