[PATCH V4] can: usb: f81604: add Fintek F81604 support

Ji-Ze Hong (Peter Hong)
2023-04-13T08:44:50Z

This patch adds support for Fintek USB to 2CAN controller.

Signed-off-by: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>
---
Changelog:
v4:
1. Remove f81604_prepare_urbs/f81604_remove_urbs() and alloc URB/buffer
dynamically in f81604_register_urbs(), using "urbs_anchor" for manage
all rx/int URBs.
2. Add F81604 to MAINTAINERS list.
3. Change handle_clear_reg_work/handle_clear_overrun_work to single
clear_reg_work and using bitwise "clear_flags" to record it.
4. Move __f81604_set_termination in front of f81604_probe() to avoid
rarely racing condition.
5. Add __aligned to struct f81604_int_data / f81604_sff / f81604_eff.
6. Add aligned operations in f81604_start_xmit/f81604_process_rx_packet().
7. Change lots of CANBUS functions first parameter from struct usb_device*
to struct f81604_port_priv *priv. But remain f81604_write / f81604_read
/ f81604_update_bits() as struct usb_device* for
__f81604_set_termination() in probe() stage.
8. Simplify f81604_read_int_callback() and separate into
f81604_handle_tx / f81604_handle_can_bus_errors() functions.

v3:
1. Change CAN clock to using MEGA units.
2. Remove USB set/get retry, only remain SJA1000 reset/operation retry.
3. Fix all numberic constant to define.
4. Add terminator control. (only 0 & 120 ohm)
5. Using struct data to represent INT/TX/RX endpoints data instead byte
arrays.
6. Error message reports changed from %d to %pe for mnemotechnic values.
7. Some bit operations are changed to FIELD_PREP().
8. Separate TX functions from f81604_read_int_callback().
9. cf->can_id |= CAN_ERR_CNT in f81604_read_int_callback to report valid
TX/RX error counts.
10. Move f81604_prepare_urbs/f81604_remove_urbs() from CAN open/close() to
USB probe/disconnect().
11. coding style refactoring.

v2:
1. coding style refactoring.
2. some const number are defined to describe itself.
3. fix wrong usage for can_get_echo_skb() in f81604_write_bulk_callback().

MAINTAINERS | 6 +
drivers/net/can/usb/Kconfig | 12 +
drivers/net/can/usb/Makefile | 1 +
drivers/net/can/usb/f81604.c | 1221 ++++++++++++++++++++++++++++++++++
4 files changed, 1240 insertions(+)
create mode 100644 drivers/net/can/usb/f81604.c

diff --git a/MAINTAINERS b/MAINTAINERS
index f375bbf3bc80..fa573f637c2f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8058,6 +8058,12 @@ S: Maintained
F: drivers/hwmon/f75375s.c
F: include/linux/f75375s.h

+FINTEK F81604 USB to 2xCANBUS DEVICE DRIVER
+M: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>
+L: linux-can@vger.kernel.org
+S: Maintained
+F: drivers/net/can/usb/f81604.c
+
FIREWIRE AUDIO DRIVERS and IEC 61883-1/6 PACKET STREAMING ENGINE
M: Clemens Ladisch <clemens@ladisch.de>
M: Takashi Sakamoto <o-takashi@sakamocchi.jp>
diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig
index 445504ababce..58fcd2b34820 100644
--- a/drivers/net/can/usb/Kconfig
+++ b/drivers/net/can/usb/Kconfig
@@ -38,6 +38,18 @@ config CAN_ETAS_ES58X
To compile this driver as a module, choose M here: the module
will be called etas_es58x.

+config CAN_F81604
+ tristate "Fintek F81604 USB to 2CAN interface"
+ help
+ This driver supports the Fintek F81604 USB to 2CAN interface.
+ The device can support CAN2.0A/B protocol and also support
+ 2 output pins to control external terminator (optional).
+
+ To compile this driver as a module, choose M here: the module will
+ be called f81604.
+
+ (see also https://www.fintek.com.tw).
+
config CAN_GS_USB
tristate "Geschwister Schneider UG and candleLight compatible interfaces"
help
diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile
index 1ea16be5743b..8b11088e9a59 100644
--- a/drivers/net/can/usb/Makefile
+++ b/drivers/net/can/usb/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_CAN_8DEV_USB) += usb_8dev.o
obj-$(CONFIG_CAN_EMS_USB) += ems_usb.o
obj-$(CONFIG_CAN_ESD_USB) += esd_usb.o
obj-$(CONFIG_CAN_ETAS_ES58X) += etas_es58x/
+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
diff --git a/drivers/net/can/usb/f81604.c b/drivers/net/can/usb/f81604.c
new file mode 100644
index 000000000000..ce83a7993c4b
--- /dev/null
+++ b/drivers/net/can/usb/f81604.c
@@ -0,0 +1,1221 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Fintek F81604 USB-to-2CAN controller driver.
+ *
+ * Copyright (C) 2023 Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>
+ */
+#include <linux/bitfield.h>
+#include <linux/netdevice.h>
+#include <linux/units.h>
+#include <linux/usb.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/platform/sja1000.h>
+
+#include <asm-generic/unaligned.h>
+
+/* vendor and product id */
+#define F81604_VENDOR_ID 0x2c42
+#define F81604_PRODUCT_ID 0x1709
+#define F81604_CAN_CLOCK (24 * MEGA / 2)
+#define F81604_MAX_DEV 2
+#define F81604_SET_DEVICE_RETRY 10
+
+#define F81604_USB_TIMEOUT 2000
+#define F81604_SET_GET_REGISTER 0xA0
+#define F81604_PORT_OFFSET 0x1000
+
+#define F81604_BULK_SIZE 64
+#define F81604_INT_SIZE 16
+#define F81604_DATA_SIZE 14
+#define F81604_MAX_RX_URBS 4
+
+#define F81604_CMD_DATA 0x00
+
+#define F81604_DLC_LEN_MASK 0x0f
+#define F81604_DLC_EFF_BIT BIT(7)
+#define F81604_DLC_RTR_BIT BIT(6)
+
+#define F81604_BRP_MASK GENMASK(5, 0)
+#define F81604_SJW_MASK GENMASK(7, 6)
+
+#define F81604_SEG1_MASK GENMASK(3, 0)
+#define F81604_SEG2_MASK GENMASK(6, 4)
+
+#define F81604_CLEAR_ALC 0
+#define F81604_CLEAR_ECC 1
+#define F81604_CLEAR_OVERRUN 2
+
+/* device setting */
+#define F81604_CTRL_MODE_REG 0x80
+#define F81604_TX_ONESHOT (0x03 << 3)
+#define F81604_TX_NORMAL (0x01 << 3)
+#define F81604_RX_AUTO_RELEASE_BUF BIT(1)
+#define F81604_INT_WHEN_CHANGE BIT(0)
+
+#define F81604_TERMINATOR_REG 0x105
+#define F81604_CAN0_TERM BIT(2)
+#define F81604_CAN1_TERM BIT(3)
+
+#define F81604_TERMINATION_DISABLED CAN_TERMINATION_DISABLED
+#define F81604_TERMINATION_ENABLED 120
+
+/* SJA1000 registers - manual section 6.4 (Pelican Mode) */
+#define F81604_SJA1000_MOD 0x00
+#define F81604_SJA1000_CMR 0x01
+#define F81604_SJA1000_IR 0x03
+#define F81604_SJA1000_IER 0x04
+#define F81604_SJA1000_ALC 0x0B
+#define F81604_SJA1000_ECC 0x0C
+#define F81604_SJA1000_RXERR 0x0E
+#define F81604_SJA1000_TXERR 0x0F
+#define F81604_SJA1000_ACCC0 0x10
+#define F81604_SJA1000_ACCM0 0x14
+#define F81604_MAX_FILTER_CNT 4
+
+/* Common registers - manual section 6.5 */
+#define F81604_SJA1000_BTR0 0x06
+#define F81604_SJA1000_BTR1 0x07
+#define F81604_SJA1000_BTR1_SAMPLE_TRIPLE BIT(7)
+#define F81604_SJA1000_OCR 0x08
+#define F81604_SJA1000_CDR 0x1F
+
+/* mode register */
+#define F81604_SJA1000_MOD_RM 0x01
+#define F81604_SJA1000_MOD_LOM 0x02
+#define F81604_SJA1000_MOD_STM 0x04
+
+/* commands */
+#define F81604_SJA1000_CMD_CDO 0x08
+
+/* interrupt sources */
+#define F81604_SJA1000_IRQ_BEI 0x80
+#define F81604_SJA1000_IRQ_ALI 0x40
+#define F81604_SJA1000_IRQ_EPI 0x20
+#define F81604_SJA1000_IRQ_DOI 0x08
+#define F81604_SJA1000_IRQ_EI 0x04
+#define F81604_SJA1000_IRQ_TI 0x02
+#define F81604_SJA1000_IRQ_RI 0x01
+#define F81604_SJA1000_IRQ_ALL 0xFF
+#define F81604_SJA1000_IRQ_OFF 0x00
+
+/* status register content */
+#define F81604_SJA1000_SR_BS 0x80
+#define F81604_SJA1000_SR_ES 0x40
+#define F81604_SJA1000_SR_TCS 0x08
+
+/* ECC register */
+#define F81604_SJA1000_ECC_SEG 0x1F
+#define F81604_SJA1000_ECC_DIR 0x20
+#define F81604_SJA1000_ECC_BIT 0x00
+#define F81604_SJA1000_ECC_FORM 0x40
+#define F81604_SJA1000_ECC_STUFF 0x80
+#define F81604_SJA1000_ECC_MASK 0xc0
+
+/* ALC register */
+#define F81604_SJA1000_ALC_MASK 0x1f
+
+/* table of devices that work with this driver */
+static const struct usb_device_id f81604_table[] = {
+ { USB_DEVICE(F81604_VENDOR_ID, F81604_PRODUCT_ID) },
+ {} /* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(usb, f81604_table);
+
+static const struct ethtool_ops f81604_ethtool_ops = {
+ .get_ts_info = ethtool_op_get_ts_info,
+};
+
+static const u16 f81604_termination[] = { F81604_TERMINATION_DISABLED,
+ F81604_TERMINATION_ENABLED };
+
+struct f81604_priv {
+ struct net_device *netdev[F81604_MAX_DEV];
+};
+
+struct f81604_port_priv {
+ struct can_priv can;
+ struct net_device *netdev;
+ struct sk_buff *echo_skb;
+
+ unsigned long clear_flags;
+ struct work_struct clear_reg_work;
+
+ struct usb_device *dev;
+ struct usb_interface *intf;
+
+ struct usb_anchor urbs_anchor;
+};
+
+/* Interrupt endpoint data format:
+ * Byte 0: Status register.
+ * Byte 1: Interrupt register.
+ * Byte 2: Interrupt enable register.
+ * Byte 3: Arbitration lost capture(ALC) register.
+ * Byte 4: Error code capture(ECC) register.
+ * Byte 5: Error warning limit register.
+ * Byte 6: RX error counter register.
+ * Byte 7: TX error counter register.
+ * Byte 8: Reserved.
+ */
+struct f81604_int_data {
+ u8 sr;
+ u8 isrc;
+ u8 ier;
+ u8 alc;
+ u8 ecc;
+ u8 ewlr;
+ u8 rxerr;
+ u8 txerr;
+ u8 val;
+} __packed __aligned(4);
+
+struct f81604_sff {
+ __be16 id;
+ u8 data[CAN_MAX_DLEN];
+} __packed __aligned(2);
+
+struct f81604_eff {
+ __be32 id;
+ u8 data[CAN_MAX_DLEN];
+} __packed __aligned(2);
+
+struct f81604_can_frame {
+ u8 cmd;
+
+ /* According for F81604 DLC define:
+ * bit 3~0: data length (0~8)
+ * bit6: is RTR flag.
+ * bit7: is EFF frame.
+ */
+ u8 dlc;
+
+ union {
+ struct f81604_sff sff;
+ struct f81604_eff eff;
+ };
+} __packed;
+
+static_assert(sizeof(struct f81604_can_frame) == F81604_DATA_SIZE);
+
+static const u8 bulk_in_addr[F81604_MAX_DEV] = { 2, 4 };
+static const u8 bulk_out_addr[F81604_MAX_DEV] = { 1, 3 };
+static const u8 int_in_addr[F81604_MAX_DEV] = { 1, 3 };
+
+static int f81604_write(struct usb_device *dev, u16 reg, u8 data)
+{
+ int ret;
+
+ ret = usb_control_msg_send(dev, 0, F81604_SET_GET_REGISTER,
+ USB_TYPE_VENDOR | USB_DIR_OUT, 0, reg,
+ &data, sizeof(data), F81604_USB_TIMEOUT,
+ GFP_KERNEL);
+ if (ret)
+ dev_err(&dev->dev, "%s: reg: %x data: %x failed: %pe\n",
+ __func__, reg, data, ERR_PTR(ret));
+
+ return ret;
+}
+
+static int f81604_read(struct usb_device *dev, u16 reg, u8 *data)
+{
+ int ret;
+
+ ret = usb_control_msg_recv(dev, 0, F81604_SET_GET_REGISTER,
+ USB_TYPE_VENDOR | USB_DIR_IN, 0, reg, data,
+ sizeof(*data), F81604_USB_TIMEOUT,
+ GFP_KERNEL);
+
+ if (ret < 0)
+ dev_err(&dev->dev, "%s: reg: %x failed: %pe\n", __func__, reg,
+ ERR_PTR(ret));
+
+ return ret;
+}
+
+static int f81604_update_bits(struct usb_device *dev, u16 reg, u8 mask,
+ u8 data)
+{
+ int ret;
+ u8 tmp;
+
+ ret = f81604_read(dev, reg, &tmp);
+ if (ret)
+ return ret;
+
+ tmp &= ~mask;
+ tmp |= (mask & data);
+
+ return f81604_write(dev, reg, tmp);
+}
+
+static int f81604_sja1000_write(struct f81604_port_priv *priv, u16 reg,
+ u8 data)
+{
+ int port = priv->netdev->dev_id;
+ int real_reg;
+
+ real_reg = reg + F81604_PORT_OFFSET * port + F81604_PORT_OFFSET;
+ return f81604_write(priv->dev, real_reg, data);
+}
+
+static int f81604_sja1000_read(struct f81604_port_priv *priv, u16 reg,
+ u8 *data)
+{
+ int port = priv->netdev->dev_id;
+ int real_reg;
+
+ real_reg = reg + F81604_PORT_OFFSET * port + F81604_PORT_OFFSET;
+ return f81604_read(priv->dev, real_reg, data);
+}
+
+static int f81604_set_reset_mode(struct f81604_port_priv *priv)
+{
+ int ret, i;
+ u8 tmp;
+
+ /* disable interrupts */
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_IER,
+ F81604_SJA1000_IRQ_OFF);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < F81604_SET_DEVICE_RETRY; i++) {
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_MOD, &tmp);
+ if (ret)
+ return ret;
+
+ /* check reset bit */
+ if (tmp & F81604_SJA1000_MOD_RM) {
+ priv->can.state = CAN_STATE_STOPPED;
+ return 0;
+ }
+
+ /* reset chip */
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_MOD,
+ F81604_SJA1000_MOD_RM);
+ if (ret)
+ return ret;
+ }
+
+ return -EPERM;
+}
+
+static int f81604_set_normal_mode(struct f81604_port_priv *priv)
+{
+ u8 tmp, ier = 0;
+ u8 mod_reg = 0;
+ int ret, i;
+
+ for (i = 0; i < F81604_SET_DEVICE_RETRY; i++) {
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_MOD, &tmp);
+ if (ret)
+ return ret;
+
+ /* check reset bit */
+ if ((tmp & F81604_SJA1000_MOD_RM) == 0) {
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ /* enable interrupts, RI handled by bulk-in */
+ ier = F81604_SJA1000_IRQ_ALL & ~F81604_SJA1000_IRQ_RI;
+ if (!(priv->can.ctrlmode &
+ CAN_CTRLMODE_BERR_REPORTING))
+ ier &= ~F81604_SJA1000_IRQ_BEI;
+
+ return f81604_sja1000_write(priv, F81604_SJA1000_IER,
+ ier);
+ }
+
+ /* set chip to normal mode */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+ mod_reg |= F81604_SJA1000_MOD_LOM;
+ if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK)
+ mod_reg |= F81604_SJA1000_MOD_STM;
+
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_MOD, mod_reg);
+ if (ret)
+ return ret;
+ }
+
+ return -EPERM;
+}
+
+static int f81604_chipset_init(struct f81604_port_priv *priv)
+{
+ int i, ret;
+
+ /* set clock divider and output control register */
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_CDR,
+ CDR_CBP | CDR_PELICAN);
+ if (ret)
+ return ret;
+
+ /* set acceptance filter (accept all) */
+ for (i = 0; i < F81604_MAX_FILTER_CNT; ++i) {
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_ACCC0 + i, 0);
+ if (ret)
+ return ret;
+ }
+
+ for (i = 0; i < F81604_MAX_FILTER_CNT; ++i) {
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_ACCM0 + i,
+ 0xFF);
+ if (ret)
+ return ret;
+ }
+
+ return f81604_sja1000_write(priv, F81604_SJA1000_OCR,
+ OCR_TX0_PUSHPULL | OCR_TX1_PUSHPULL |
+ OCR_MODE_NORMAL);
+}
+
+static void f81604_process_rx_packet(struct urb *urb)
+{
+ struct net_device *netdev = urb->context;
+ struct net_device_stats *stats;
+ struct f81604_can_frame *frame;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ unsigned int count;
+ unsigned int i;
+ u8 *data;
+
+ data = urb->transfer_buffer;
+ stats = &netdev->stats;
+
+ if (urb->actual_length % F81604_DATA_SIZE)
+ netdev_warn(netdev, "URB length %u not multiple of %u\n",
+ urb->actual_length, F81604_DATA_SIZE);
+ else if (!urb->actual_length)
+ netdev_warn(netdev, "URB length is 0\n");
+
+ count = urb->actual_length / F81604_DATA_SIZE;
+
+ for (i = 0; i < count; ++i) {
+ frame = (struct f81604_can_frame *)&data[i * F81604_DATA_SIZE];
+
+ if (frame->cmd != F81604_CMD_DATA)
+ continue;
+
+ skb = alloc_can_skb(netdev, &cf);
+ if (!skb) {
+ stats->rx_dropped++;
+ continue;
+ }
+
+ cf->len = can_cc_dlc2len(frame->dlc & F81604_DLC_LEN_MASK);
+
+ if (frame->dlc & F81604_DLC_EFF_BIT) {
+ cf->can_id = get_unaligned_be32(&frame->eff.id) >> 3;
+ cf->can_id |= CAN_EFF_FLAG;
+
+ if (cf->len)
+ memcpy(cf->data, frame->eff.data, cf->len);
+ } else {
+ cf->can_id = get_unaligned_be16(&frame->sff.id) >> 5;
+
+ if (cf->len)
+ memcpy(cf->data, frame->sff.data, cf->len);
+ }
+
+ if (frame->dlc & F81604_DLC_RTR_BIT)
+ cf->can_id |= CAN_RTR_FLAG;
+ else
+ stats->rx_bytes += cf->len;
+
+ stats->rx_packets++;
+ netif_rx(skb);
+ }
+}
+
+static void f81604_read_bulk_callback(struct urb *urb)
+{
+ struct net_device *netdev = urb->context;
+ int ret;
+
+ if (!netif_device_present(netdev))
+ return;
+
+ if (urb->status)
+ netdev_info(netdev, "%s: URB aborted %pe\n", __func__,
+ ERR_PTR(urb->status));
+
+ switch (urb->status) {
+ case 0: /* success */
+ break;
+
+ case -ENOENT:
+ case -EPIPE:
+ case -EPROTO:
+ case -ESHUTDOWN:
+ return;
+
+ default:
+ goto resubmit_urb;
+ }
+
+ f81604_process_rx_packet(urb);
+
+resubmit_urb:
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret == -ENODEV)
+ netif_device_detach(netdev);
+ else if (ret)
+ netdev_err(netdev,
+ "%s: failed to resubmit read bulk urb: %pe\n",
+ __func__, ERR_PTR(ret));
+}
+
+static void f81604_handle_tx(struct f81604_port_priv *priv,
+ struct f81604_int_data *data)
+{
+ struct net_device *netdev = priv->netdev;
+ struct net_device_stats *stats;
+
+ stats = &netdev->stats;
+
+ /* transmission buffer released */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
+ !(data->sr & F81604_SJA1000_SR_TCS)) {
+ stats->tx_errors++;
+ can_free_echo_skb(netdev, 0, NULL);
+ } else {
+ /* transmission complete */
+ stats->tx_bytes += can_get_echo_skb(netdev, 0, NULL);
+ stats->tx_packets++;
+ }
+
+ netif_wake_queue(netdev);
+}
+
+static void f81604_handle_can_bus_errors(struct f81604_port_priv *priv,
+ struct f81604_int_data *data)
+{
+ enum can_state can_state = priv->can.state;
+ struct net_device *netdev = priv->netdev;
+ enum can_state tx_state, rx_state;
+ struct net_device_stats *stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+
+ stats = &netdev->stats;
+
+ /* Note: ALC/ECC will not auto clear by read here, must be cleared by
+ * read register (via clear_reg_work).
+ */
+
+ skb = alloc_can_err_skb(netdev, &cf);
+ if (skb) {
+ cf->can_id |= CAN_ERR_CNT;
+ cf->data[6] = data->txerr;
+ cf->data[7] = data->rxerr;
+ }
+
+ if (data->isrc & F81604_SJA1000_IRQ_DOI) {
+ /* data overrun interrupt */
+ netdev_dbg(netdev, "data overrun interrupt\n");
+
+ if (skb) {
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+ }
+
+ stats->rx_over_errors++;
+ stats->rx_errors++;
+
+ set_bit(F81604_CLEAR_OVERRUN, &priv->clear_flags);
+ }
+
+ if (data->isrc & F81604_SJA1000_IRQ_EI) {
+ /* error warning interrupt */
+ netdev_dbg(netdev, "error warning interrupt\n");
+
+ if (data->sr & F81604_SJA1000_SR_BS)
+ can_state = CAN_STATE_BUS_OFF;
+ else if (data->sr & F81604_SJA1000_SR_ES)
+ can_state = CAN_STATE_ERROR_WARNING;
+ else
+ can_state = CAN_STATE_ERROR_ACTIVE;
+ }
+
+ if (data->isrc & F81604_SJA1000_IRQ_BEI) {
+ /* bus error interrupt */
+ netdev_dbg(netdev, "bus error interrupt\n");
+
+ priv->can.can_stats.bus_error++;
+ stats->rx_errors++;
+
+ if (skb) {
+ cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+ /* set error type */
+ switch (data->ecc & F81604_SJA1000_ECC_MASK) {
+ case F81604_SJA1000_ECC_BIT:
+ cf->data[2] |= CAN_ERR_PROT_BIT;
+ break;
+ case F81604_SJA1000_ECC_FORM:
+ cf->data[2] |= CAN_ERR_PROT_FORM;
+ break;
+ case F81604_SJA1000_ECC_STUFF:
+ cf->data[2] |= CAN_ERR_PROT_STUFF;
+ break;
+ default:
+ break;
+ }
+
+ /* set error location */
+ cf->data[3] = data->ecc & F81604_SJA1000_ECC_SEG;
+
+ /* Error occurred during transmission? */
+ if ((data->ecc & F81604_SJA1000_ECC_DIR) == 0)
+ cf->data[2] |= CAN_ERR_PROT_TX;
+ }
+
+ set_bit(F81604_CLEAR_ECC, &priv->clear_flags);
+ }
+
+ if (data->isrc & F81604_SJA1000_IRQ_EPI) {
+ if (can_state == CAN_STATE_ERROR_PASSIVE)
+ can_state = CAN_STATE_ERROR_WARNING;
+ else
+ can_state = CAN_STATE_ERROR_PASSIVE;
+
+ /* error passive interrupt */
+ netdev_dbg(netdev, "error passive interrupt: %d\n", can_state);
+ }
+
+ if (data->isrc & F81604_SJA1000_IRQ_ALI) {
+ /* arbitration lost interrupt */
+ netdev_dbg(netdev, "arbitration lost interrupt\n");
+
+ priv->can.can_stats.arbitration_lost++;
+
+ if (skb) {
+ cf->can_id |= CAN_ERR_LOSTARB;
+ cf->data[0] = data->alc & F81604_SJA1000_ALC_MASK;
+ }
+
+ set_bit(F81604_CLEAR_ALC, &priv->clear_flags);
+ }
+
+ if (can_state != priv->can.state) {
+ tx_state = data->txerr >= data->rxerr ? can_state : 0;
+ rx_state = data->txerr <= data->rxerr ? can_state : 0;
+
+ can_change_state(netdev, cf, tx_state, rx_state);
+
+ if (can_state == CAN_STATE_BUS_OFF)
+ can_bus_off(netdev);
+ }
+
+ if (priv->clear_flags)
+ schedule_work(&priv->clear_reg_work);
+
+ if (skb)
+ netif_rx(skb);
+}
+
+static void f81604_read_int_callback(struct urb *urb)
+{
+ struct f81604_int_data *data = urb->transfer_buffer;
+ struct net_device *netdev = urb->context;
+ struct f81604_port_priv *priv;
+ int ret;
+
+ priv = netdev_priv(netdev);
+
+ if (!netif_device_present(netdev))
+ return;
+
+ if (urb->status)
+ netdev_info(netdev, "%s: Int URB aborted: %pe\n", __func__,
+ ERR_PTR(urb->status));
+
+ switch (urb->status) {
+ case 0: /* success */
+ break;
+
+ case -ENOENT:
+ case -EPIPE:
+ case -EPROTO:
+ case -ESHUTDOWN:
+ return;
+
+ default:
+ goto resubmit_urb;
+ }
+
+ /* handle Errors */
+ if (data->isrc & (F81604_SJA1000_IRQ_DOI | F81604_SJA1000_IRQ_EI |
+ F81604_SJA1000_IRQ_BEI | F81604_SJA1000_IRQ_EPI |
+ F81604_SJA1000_IRQ_ALI))
+ f81604_handle_can_bus_errors(priv, data);
+
+ /* handle TX */
+ if (priv->can.state != CAN_STATE_BUS_OFF &&
+ (data->isrc & F81604_SJA1000_IRQ_TI))
+ f81604_handle_tx(priv, data);
+
+resubmit_urb:
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret == -ENODEV)
+ netif_device_detach(netdev);
+ else if (ret)
+ netdev_err(netdev, "%s: failed to resubmit int urb: %pe\n",
+ __func__, ERR_PTR(ret));
+}
+
+static void f81604_unregister_urbs(struct f81604_port_priv *priv)
+{
+ usb_kill_anchored_urbs(&priv->urbs_anchor);
+}
+
+static int f81604_register_urbs(struct f81604_port_priv *priv)
+{
+ struct net_device *netdev = priv->netdev;
+ struct urb *rx_urb, *int_urb;
+ int id = netdev->dev_id;
+ u8 *rx_buf, *int_buf;
+ int rx_urb_cnt;
+ int ret;
+
+ for (rx_urb_cnt = 0; rx_urb_cnt < F81604_MAX_RX_URBS; ++rx_urb_cnt) {
+ rx_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!rx_urb) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ rx_buf = kmalloc(F81604_BULK_SIZE, GFP_KERNEL);
+ if (!rx_buf) {
+ usb_free_urb(rx_urb);
+ ret = -ENOMEM;
+ break;
+ }
+
+ usb_fill_bulk_urb(rx_urb, priv->dev,
+ usb_rcvbulkpipe(priv->dev, bulk_in_addr[id]),
+ rx_buf, F81604_BULK_SIZE,
+ f81604_read_bulk_callback, netdev);
+
+ rx_urb->transfer_flags |= URB_FREE_BUFFER;
+ usb_anchor_urb(rx_urb, &priv->urbs_anchor);
+
+ ret = usb_submit_urb(rx_urb, GFP_KERNEL);
+ if (ret) {
+ usb_unanchor_urb(rx_urb);
+ usb_free_urb(rx_urb);
+
+ break;
+ }
+
+ /* Drop reference, USB core will take care of freeing it */
+ usb_free_urb(rx_urb);
+ }
+
+ if (rx_urb_cnt == 0) {
+ netdev_warn(netdev, "%s: submit rx urb failed: %pe\n",
+ __func__, ERR_PTR(ret));
+
+ goto error;
+ }
+
+ int_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!int_urb) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ int_buf = kmalloc(F81604_BULK_SIZE, GFP_KERNEL);
+ if (!int_buf) {
+ usb_free_urb(int_urb);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ usb_fill_int_urb(int_urb, priv->dev,
+ usb_rcvintpipe(priv->dev, int_in_addr[id]), int_buf,
+ F81604_INT_SIZE, f81604_read_int_callback, netdev, 1);
+
+ int_urb->transfer_flags |= URB_FREE_BUFFER;
+ usb_anchor_urb(int_urb, &priv->urbs_anchor);
+
+ ret = usb_submit_urb(int_urb, GFP_KERNEL);
+ if (ret) {
+ usb_unanchor_urb(int_urb);
+ usb_free_urb(int_urb);
+
+ netdev_warn(netdev, "%s: submit int urb failed: %pe\n",
+ __func__, ERR_PTR(ret));
+ goto error;
+ }
+
+ /* Drop reference, USB core will take care of freeing it */
+ usb_free_urb(int_urb);
+
+ return 0;
+
+error:
+ f81604_unregister_urbs(priv);
+ return ret;
+}
+
+static int f81604_start(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int ret;
+ u8 mode;
+ u8 tmp;
+
+ mode = F81604_RX_AUTO_RELEASE_BUF | F81604_INT_WHEN_CHANGE;
+
+ /* Set TR/AT mode */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
+ mode |= F81604_TX_ONESHOT;
+ else
+ mode |= F81604_TX_NORMAL;
+
+ ret = f81604_sja1000_write(priv, F81604_CTRL_MODE_REG, mode);
+ if (ret)
+ return ret;
+
+ /* set reset mode */
+ ret = f81604_set_reset_mode(priv);
+ if (ret)
+ return ret;
+
+ ret = f81604_chipset_init(priv);
+ if (ret)
+ return ret;
+
+ /* Clear error counters and error code capture */
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_TXERR, 0);
+ if (ret)
+ return ret;
+
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_RXERR, 0);
+ if (ret)
+ return ret;
+
+ /* Read clear for ECC/ALC/IR register */
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_ECC, &tmp);
+ if (ret)
+ return ret;
+
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_ALC, &tmp);
+ if (ret)
+ return ret;
+
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_IR, &tmp);
+ if (ret)
+ return ret;
+
+ ret = f81604_register_urbs(priv);
+ if (ret)
+ return ret;
+
+ ret = f81604_set_normal_mode(priv);
+ if (ret) {
+ f81604_unregister_urbs(priv);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int f81604_set_bittiming(struct net_device *dev)
+{
+ struct f81604_port_priv *priv = netdev_priv(dev);
+ struct can_bittiming *bt = &priv->can.bittiming;
+ u8 btr0, btr1;
+ int ret;
+
+ btr0 = FIELD_PREP(F81604_BRP_MASK, bt->brp - 1) |
+ FIELD_PREP(F81604_SJW_MASK, bt->sjw - 1);
+
+ btr1 = FIELD_PREP(F81604_SEG1_MASK,
+ bt->prop_seg + bt->phase_seg1 - 1) |
+ FIELD_PREP(F81604_SEG2_MASK, bt->phase_seg2 - 1);
+
+ if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+ btr1 |= F81604_SJA1000_BTR1_SAMPLE_TRIPLE;
+
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_BTR0, btr0);
+ if (ret) {
+ netdev_warn(dev, "%s: Set BTR0 failed: %pe\n", __func__,
+ ERR_PTR(ret));
+ return ret;
+ }
+
+ ret = f81604_sja1000_write(priv, F81604_SJA1000_BTR1, btr1);
+ if (ret) {
+ netdev_warn(dev, "%s: Set BTR1 failed: %pe\n", __func__,
+ ERR_PTR(ret));
+ return ret;
+ }
+
+ return 0;
+}
+
+static int f81604_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+ int ret;
+
+ switch (mode) {
+ case CAN_MODE_START:
+ ret = f81604_start(netdev);
+ if (!ret && netif_queue_stopped(netdev))
+ netif_wake_queue(netdev);
+ break;
+
+ default:
+ ret = -EOPNOTSUPP;
+ }
+
+ return ret;
+}
+
+static void f81604_write_bulk_callback(struct urb *urb)
+{
+ struct net_device *netdev = urb->context;
+
+ if (!netif_device_present(netdev))
+ return;
+
+ if (urb->status)
+ netdev_info(netdev, "%s: Tx URB error: %pe\n", __func__,
+ ERR_PTR(urb->status));
+}
+
+static void f81604_clear_reg_work(struct work_struct *work)
+{
+ struct f81604_port_priv *priv;
+ struct net_device *netdev;
+ u8 tmp;
+
+ priv = container_of(work, struct f81604_port_priv, clear_reg_work);
+ netdev = priv->netdev;
+
+ /* dummy read for clear Arbitration lost capture(ALC) register. */
+ if (test_and_clear_bit(F81604_CLEAR_ALC, &priv->clear_flags))
+ f81604_sja1000_read(priv, F81604_SJA1000_ALC, &tmp);
+
+ /* dummy read for clear Error code capture(ECC) register. */
+ if (test_and_clear_bit(F81604_CLEAR_ECC, &priv->clear_flags))
+ f81604_sja1000_read(priv, F81604_SJA1000_ECC, &tmp);
+
+ /* dummy write for clear data overrun flag. */
+ if (test_and_clear_bit(F81604_CLEAR_OVERRUN, &priv->clear_flags))
+ f81604_sja1000_write(priv, F81604_SJA1000_CMR,
+ F81604_SJA1000_CMD_CDO);
+}
+
+static netdev_tx_t f81604_start_xmit(struct sk_buff *skb,
+ struct net_device *netdev)
+{
+ struct can_frame *cf = (struct can_frame *)skb->data;
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ struct net_device_stats *stats = &netdev->stats;
+ struct f81604_can_frame *frame;
+ u32 id = priv->netdev->dev_id;
+ struct urb *write_urb;
+ u8 *bulk_write_buffer;
+ int ret;
+
+ if (can_dev_dropped_skb(netdev, skb))
+ return NETDEV_TX_OK;
+
+ netif_stop_queue(netdev);
+
+ write_urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!write_urb)
+ goto nomem_urb;
+
+ bulk_write_buffer = kzalloc(F81604_DATA_SIZE, GFP_ATOMIC);
+ if (!bulk_write_buffer)
+ goto nomem_buf;
+
+ usb_fill_bulk_urb(write_urb, priv->dev,
+ usb_sndbulkpipe(priv->dev, bulk_out_addr[id]),
+ bulk_write_buffer, F81604_DATA_SIZE,
+ f81604_write_bulk_callback, priv->netdev);
+
+ write_urb->transfer_flags |= URB_FREE_BUFFER;
+
+ frame = (struct f81604_can_frame *)bulk_write_buffer;
+ frame->cmd = F81604_CMD_DATA;
+ frame->dlc = cf->len;
+
+ if (cf->can_id & CAN_RTR_FLAG)
+ frame->dlc |= F81604_DLC_RTR_BIT;
+
+ if (cf->can_id & CAN_EFF_FLAG) {
+ id = (cf->can_id & CAN_EFF_MASK) << 3;
+ put_unaligned_be32(id, &frame->eff.id);
+
+ frame->dlc |= F81604_DLC_EFF_BIT;
+
+ if (!(cf->can_id & CAN_RTR_FLAG))
+ memcpy(&frame->eff.data, cf->data, cf->len);
+ } else {
+ id = (cf->can_id & CAN_SFF_MASK) << 5;
+ put_unaligned_be16(id, &frame->sff.id);
+
+ if (!(cf->can_id & CAN_RTR_FLAG))
+ memcpy(&frame->sff.data, cf->data, cf->len);
+ }
+
+ can_put_echo_skb(skb, netdev, 0, 0);
+
+ ret = usb_submit_urb(write_urb, GFP_ATOMIC);
+ if (ret) {
+ netdev_err(netdev, "%s: failed to resubmit tx bulk urb: %pe\n",
+ __func__, ERR_PTR(ret));
+
+ can_free_echo_skb(netdev, 0, NULL);
+ stats->tx_dropped++;
+
+ if (ret == -ENODEV)
+ netif_device_detach(netdev);
+ else
+ netif_wake_queue(netdev);
+ }
+
+ /* let usb core take care of this urb */
+ usb_free_urb(write_urb);
+
+ return NETDEV_TX_OK;
+
+nomem_buf:
+ usb_free_urb(write_urb);
+
+nomem_urb:
+ dev_kfree_skb(skb);
+ stats->tx_dropped++;
+ netif_wake_queue(netdev);
+
+ return NETDEV_TX_OK;
+}
+
+static int f81604_get_berr_counter(const struct net_device *netdev,
+ struct can_berr_counter *bec)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ u8 txerr, rxerr;
+ int ret;
+
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_TXERR, &txerr);
+ if (ret)
+ return ret;
+
+ ret = f81604_sja1000_read(priv, F81604_SJA1000_RXERR, &rxerr);
+ if (ret)
+ return ret;
+
+ bec->txerr = txerr;
+ bec->rxerr = rxerr;
+
+ return 0;
+}
+
+/* Open USB device */
+static int f81604_open(struct net_device *netdev)
+{
+ int ret;
+
+ ret = open_candev(netdev);
+ if (ret)
+ return ret;
+
+ ret = f81604_start(netdev);
+ if (ret)
+ goto start_failed;
+
+ netif_start_queue(netdev);
+ return 0;
+
+start_failed:
+ if (ret == -ENODEV)
+ netif_device_detach(netdev);
+
+ close_candev(netdev);
+
+ return ret;
+}
+
+/* Close USB device */
+static int f81604_close(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+
+ f81604_set_reset_mode(priv);
+
+ netif_stop_queue(netdev);
+ cancel_work_sync(&priv->clear_reg_work);
+ close_candev(netdev);
+
+ f81604_unregister_urbs(priv);
+
+ return 0;
+}
+
+static const struct net_device_ops f81604_netdev_ops = {
+ .ndo_open = f81604_open,
+ .ndo_stop = f81604_close,
+ .ndo_start_xmit = f81604_start_xmit,
+ .ndo_change_mtu = can_change_mtu,
+};
+
+static const struct can_bittiming_const f81604_bittiming_const = {
+ .name = KBUILD_MODNAME,
+ .tseg1_min = 1,
+ .tseg1_max = 16,
+ .tseg2_min = 1,
+ .tseg2_max = 8,
+ .sjw_max = 4,
+ .brp_min = 1,
+ .brp_max = 64,
+ .brp_inc = 1,
+};
+
+/* Called by the usb core when driver is unloaded or device is removed */
+static void f81604_disconnect(struct usb_interface *intf)
+{
+ struct f81604_priv *priv = usb_get_intfdata(intf);
+ struct f81604_port_priv *port_priv;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(priv->netdev); ++i) {
+ if (!priv->netdev[i])
+ continue;
+
+ port_priv = netdev_priv(priv->netdev[i]);
+
+ unregister_netdev(priv->netdev[i]);
+ free_candev(priv->netdev[i]);
+ }
+}
+
+static int __f81604_set_termination(struct usb_device *dev, int idx, u16 term)
+{
+ u8 mask, data = 0;
+
+ if (idx == 0)
+ mask = F81604_CAN0_TERM;
+ else
+ mask = F81604_CAN1_TERM;
+
+ if (term)
+ data = mask;
+
+ return f81604_update_bits(dev, F81604_TERMINATOR_REG, mask, data);
+}
+
+static int f81604_set_termination(struct net_device *netdev, u16 term)
+{
+ struct f81604_port_priv *port_priv = netdev_priv(netdev);
+
+ ASSERT_RTNL();
+
+ return __f81604_set_termination(port_priv->dev, netdev->dev_id, term);
+}
+
+static int f81604_probe(struct usb_interface *intf,
+ const struct usb_device_id *id)
+{
+ struct usb_device *dev = interface_to_usbdev(intf);
+ struct f81604_port_priv *port_priv;
+ struct net_device *netdev;
+ struct f81604_priv *priv;
+ int i, ret;
+
+ priv = devm_kzalloc(&intf->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ usb_set_intfdata(intf, priv);
+
+ for (i = 0; i < ARRAY_SIZE(priv->netdev); ++i) {
+ ret = __f81604_set_termination(dev, i, 0);
+ if (ret) {
+ dev_err(&intf->dev,
+ "Set can%d termination failed: %pe\n", i,
+ ERR_PTR(ret));
+ return ret;
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(priv->netdev); ++i) {
+ netdev = alloc_candev(sizeof(*port_priv), 1);
+ if (!netdev) {
+ dev_err(&intf->dev, "Couldn't alloc candev: %d\n", i);
+ ret = -ENOMEM;
+
+ goto failure_cleanup;
+ }
+
+ port_priv = netdev_priv(netdev);
+ netdev->dev_id = i;
+
+ INIT_WORK(&port_priv->clear_reg_work, f81604_clear_reg_work);
+ init_usb_anchor(&port_priv->urbs_anchor);
+
+ port_priv->intf = intf;
+ port_priv->dev = dev;
+ port_priv->netdev = netdev;
+ port_priv->can.clock.freq = F81604_CAN_CLOCK;
+
+ port_priv->can.termination_const = f81604_termination;
+ port_priv->can.termination_const_cnt =
+ ARRAY_SIZE(f81604_termination);
+ port_priv->can.bittiming_const = &f81604_bittiming_const;
+ port_priv->can.do_set_bittiming = f81604_set_bittiming;
+ port_priv->can.do_set_mode = f81604_set_mode;
+ port_priv->can.do_set_termination = f81604_set_termination;
+ port_priv->can.do_get_berr_counter = f81604_get_berr_counter;
+ port_priv->can.ctrlmode_supported =
+ CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_3_SAMPLES |
+ CAN_CTRLMODE_ONE_SHOT | CAN_CTRLMODE_BERR_REPORTING |
+ CAN_CTRLMODE_PRESUME_ACK;
+
+ netdev->ethtool_ops = &f81604_ethtool_ops;
+ netdev->netdev_ops = &f81604_netdev_ops;
+ netdev->flags |= IFF_ECHO;
+
+ SET_NETDEV_DEV(netdev, &intf->dev);
+
+ ret = register_candev(netdev);
+ if (ret) {
+ netdev_err(netdev, "register CAN device failed: %pe\n",
+ ERR_PTR(ret));
+ free_candev(netdev);
+
+ goto failure_cleanup;
+ }
+
+ priv->netdev[i] = netdev;
+
+ dev_info(&intf->dev, "Channel #%d registered as %s\n", i,
+ netdev->name);
+ }
+
+ return 0;
+
+failure_cleanup:
+ f81604_disconnect(intf);
+ return ret;
+}
+
+static struct usb_driver f81604_driver = {
+ .name = KBUILD_MODNAME,
+ .probe = f81604_probe,
+ .disconnect = f81604_disconnect,
+ .id_table = f81604_table,
+};
+
+module_usb_driver(f81604_driver);
+
+MODULE_AUTHOR("Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>");
+MODULE_DESCRIPTION("Fintek F81604 USB to 2xCANBUS");
+MODULE_LICENSE("GPL");
--
2.17.1