2023-03-17 10:58:38

by Peter Hong

[permalink] [raw]
Subject: [PATCH] can: usb: f81604: add Fintek F81604 support

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

Signed-off-by: Ji-Ze Hong (Peter Hong) <[email protected]>
---
drivers/net/can/usb/Kconfig | 9 +
drivers/net/can/usb/Makefile | 1 +
drivers/net/can/usb/f81604.c | 1215 ++++++++++++++++++++++++++++++++++
3 files changed, 1225 insertions(+)
create mode 100644 drivers/net/can/usb/f81604.c

diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig
index 445504ababce..381547939c39 100644
--- a/drivers/net/can/usb/Kconfig
+++ b/drivers/net/can/usb/Kconfig
@@ -147,4 +147,13 @@ config CAN_UCAN
from Theobroma Systems like the A31-µQ7 and the RK3399-Q7
(https://www.theobroma-systems.com/rk3399-q7)

+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).
+
+ (see also https://www.fintek.com.tw).
+
endmenu
diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile
index 1ea16be5743b..9de0305a5cce 100644
--- a/drivers/net/can/usb/Makefile
+++ b/drivers/net/can/usb/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb/
obj-$(CONFIG_CAN_MCBA_USB) += mcba_usb.o
obj-$(CONFIG_CAN_PEAK_USB) += peak_usb/
obj-$(CONFIG_CAN_UCAN) += ucan.o
+obj-$(CONFIG_CAN_F81604) += f81604.o
diff --git a/drivers/net/can/usb/f81604.c b/drivers/net/can/usb/f81604.c
new file mode 100644
index 000000000000..166f5789247e
--- /dev/null
+++ b/drivers/net/can/usb/f81604.c
@@ -0,0 +1,1215 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Fintek F81604 USB-to-2CAN controller driver.
+ *
+ * Copyright (C) 2023 Ji-Ze Hong (Peter Hong) <[email protected]>
+ */
+#include <linux/netdevice.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>
+
+/* vendor and product id */
+#define F81604_VENDOR_ID 0x2c42
+#define F81604_PRODUCT_ID 0x1709
+#define F81604_MAX_DEV 2
+
+#define F81604_USB_MAX_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_OFFSET 0x00
+#define F81604_CMD_DATA 0x00
+
+#define F81604_DLC_OFFSET 0x01
+#define F81604_LEN_MASK 0x0f
+#define F81604_EFF_BIT BIT(7)
+#define F81604_RTR_BIT BIT(6)
+
+#define F81604_ID1_OFFSET 0x02
+#define F81604_ID2_OFFSET 0x03
+#define F81604_ID3_OFFSET 0x04
+#define F81604_ID4_OFFSET 0x05
+
+#define F81604_SFF_DATA_OFFSET 0x04
+#define F81604_EFF_DATA_OFFSET 0x06
+
+/* device setting */
+#define F81604_TX_ONESHOT (0x03 << 3)
+#define F81604_TX_NORMAL (0x01 << 3)
+#define F81604_RX_AUTO_RELEASE_BUF (0x01 << 1)
+#define F81604_INT_WHEN_CHANGE (0x01 << 0)
+
+/* SJA1000 registers - manual section 6.4 (Pelican Mode) */
+#define SJA1000_MOD 0x00
+#define SJA1000_CMR 0x01
+#define SJA1000_IR 0x03
+#define SJA1000_IER 0x04
+#define SJA1000_ALC 0x0B
+#define SJA1000_ECC 0x0C
+#define SJA1000_RXERR 0x0E
+#define SJA1000_TXERR 0x0F
+#define SJA1000_ACCC0 0x10
+#define SJA1000_ACCC1 0x11
+#define SJA1000_ACCC2 0x12
+#define SJA1000_ACCC3 0x13
+#define SJA1000_ACCM0 0x14
+#define SJA1000_ACCM1 0x15
+#define SJA1000_ACCM2 0x16
+#define SJA1000_ACCM3 0x17
+
+/* Common registers - manual section 6.5 */
+#define SJA1000_BTR0 0x06
+#define SJA1000_BTR1 0x07
+#define SJA1000_OCR 0x08
+#define SJA1000_CDR 0x1F
+
+#define SJA1000_FI 0x10
+#define SJA1000_SFF_BUF 0x13
+#define SJA1000_EFF_BUF 0x15
+
+#define SJA1000_FI_FF 0x80
+#define SJA1000_FI_RTR 0x40
+
+#define SJA1000_ID1 0x11
+#define SJA1000_ID2 0x12
+#define SJA1000_ID3 0x13
+#define SJA1000_ID4 0x14
+
+/* mode register */
+#define MOD_RM 0x01
+#define MOD_LOM 0x02
+#define MOD_STM 0x04
+
+/* commands */
+#define CMD_CDO 0x08
+
+/* interrupt sources */
+#define IRQ_BEI 0x80
+#define IRQ_ALI 0x40
+#define IRQ_EPI 0x20
+#define IRQ_DOI 0x08
+#define IRQ_EI 0x04
+#define IRQ_TI 0x02
+#define IRQ_RI 0x01
+#define IRQ_ALL 0xFF
+#define IRQ_OFF 0x00
+
+/* status register content */
+#define SR_BS 0x80
+#define SR_ES 0x40
+#define SR_TS 0x20
+#define SR_RS 0x10
+#define SR_TCS 0x08
+#define SR_TBS 0x04
+#define SR_DOS 0x02
+#define SR_RBS 0x01
+
+/* ECC register */
+#define ECC_SEG 0x1F
+#define ECC_DIR 0x20
+#define ECC_BIT 0x00
+#define ECC_FORM 0x40
+#define ECC_STUFF 0x80
+#define ECC_MASK 0xc0
+
+/* 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);
+
+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;
+
+ /* For synchronize need_clear_alc/need_clear_ecc in worker & interrupt
+ * callback.
+ */
+ spinlock_t lock;
+ bool need_clear_alc;
+ bool need_clear_ecc;
+
+ struct work_struct handle_clear_reg_work;
+ struct work_struct handle_clear_overrun_work;
+
+ struct usb_device *dev;
+ struct usb_interface *intf;
+
+ struct urb *int_urb;
+ u8 int_read_buffer[F81604_INT_SIZE];
+
+ struct urb *read_urb[F81604_MAX_RX_URBS];
+ u8 bulk_read_buffer[F81604_MAX_RX_URBS][F81604_BULK_SIZE];
+
+ struct urb *write_urb;
+ u8 bulk_write_buffer[F81604_DATA_SIZE];
+
+ u8 ocr;
+ u8 cdr;
+};
+
+static int f81604_set_register(struct usb_device *dev, u16 reg, u8 data)
+{
+ size_t count = F81604_USB_MAX_RETRY;
+ int status;
+
+ while (count--) {
+ status = usb_control_msg_send(dev, 0, F81604_SET_GET_REGISTER,
+ USB_TYPE_VENDOR | USB_DIR_OUT, 0,
+ reg, &data, sizeof(u8),
+ F81604_USB_TIMEOUT, GFP_KERNEL);
+ if (!status)
+ break;
+ }
+
+ if (status) {
+ dev_err(&dev->dev, "%s: reg: %x data: %x failed: %d\n",
+ __func__, reg, data, status);
+ }
+
+ return status;
+}
+
+static int f81604_get_register(struct usb_device *dev, u16 reg, u8 *data)
+{
+ size_t count = F81604_USB_MAX_RETRY;
+ int status;
+
+ while (count--) {
+ status = usb_control_msg_recv(dev, 0, F81604_SET_GET_REGISTER,
+ USB_TYPE_VENDOR | USB_DIR_IN, 0,
+ reg, data, sizeof(u8),
+ F81604_USB_TIMEOUT, GFP_KERNEL);
+ if (!status)
+ break;
+ }
+
+ if (status < 0) {
+ dev_err(&dev->dev, "%s: reg: %x failed: %d\n", __func__, reg,
+ status);
+ }
+
+ return status;
+}
+
+static int f81604_set_sja1000_register(struct usb_device *dev, u8 port,
+ u16 reg, u8 data)
+{
+ int real_reg;
+
+ real_reg = reg + F81604_PORT_OFFSET * port + F81604_PORT_OFFSET;
+ return f81604_set_register(dev, real_reg, data);
+}
+
+static int f81604_get_sja1000_register(struct usb_device *dev, u8 port,
+ u16 reg, u8 *data)
+{
+ int real_reg;
+
+ real_reg = reg + F81604_PORT_OFFSET * port + F81604_PORT_OFFSET;
+ return f81604_get_register(dev, real_reg, data);
+}
+
+static int f81604_set_reset_mode(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int status, i;
+ u8 tmp;
+
+ /* disable interrupts */
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_IER, IRQ_OFF);
+ if (status)
+ return status;
+
+ for (i = 0; i < 100; i++) {
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_MOD, &tmp);
+ if (status)
+ return status;
+
+ /* check reset bit */
+ if (tmp & MOD_RM) {
+ priv->can.state = CAN_STATE_STOPPED;
+ return 0;
+ }
+
+ /* reset chip */
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_MOD, MOD_RM);
+ if (status)
+ return status;
+ }
+
+ netdev_err(netdev, "setting SJA1000 into reset mode failed!\n");
+ return -EINVAL;
+}
+
+static int f81604_set_normal_mode(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int status, i;
+ u8 mod_reg_val = 0x00;
+ u8 ier = 0;
+ u8 tmp;
+
+ for (i = 0; i < 100; i++) {
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_MOD, &tmp);
+ if (status)
+ return status;
+
+ /* check reset bit */
+ if ((tmp & MOD_RM) == 0) {
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ /* enable interrupts, RI handled by bulk-in */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+ ier = IRQ_ALL & ~IRQ_RI;
+ else
+ ier = IRQ_ALL & ~(IRQ_RI | IRQ_BEI);
+
+ status = f81604_set_sja1000_register(priv->dev,
+ netdev->dev_id,
+ SJA1000_IER,
+ ier);
+
+ return status;
+ }
+
+ /* set chip to normal mode */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+ mod_reg_val |= MOD_LOM;
+ if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK)
+ mod_reg_val |= MOD_STM;
+
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_MOD, mod_reg_val);
+ if (status)
+ return status;
+ }
+
+ netdev_err(netdev, "setting SJA1000 into normal mode failed!\n");
+ return -EINVAL;
+}
+
+static int f81604_chipset_init(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int status;
+ int i;
+
+ /* set clock divider and output control register */
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_CDR,
+ priv->cdr | CDR_PELICAN);
+ if (status)
+ return status;
+
+ /* set acceptance filter (accept all) */
+ for (i = 0; i < 4; ++i) {
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_ACCC0 + i, 0);
+ if (status)
+ return status;
+ }
+
+ for (i = 0; i < 4; ++i) {
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_ACCM0 + i, 0xFF);
+ if (status)
+ return status;
+ }
+
+ return f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_OCR,
+ priv->ocr | OCR_MODE_NORMAL);
+}
+
+static void f81604_unregister_urbs(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int i;
+
+ usb_kill_urb(priv->write_urb);
+
+ for (i = 0; i < F81604_MAX_RX_URBS; ++i)
+ usb_kill_urb(priv->read_urb[i]);
+
+ usb_kill_urb(priv->int_urb);
+}
+
+static int f81604_register_urbs(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int status, i;
+
+ for (i = 0; i < F81604_MAX_RX_URBS; ++i) {
+ status = usb_submit_urb(priv->read_urb[i], GFP_KERNEL);
+ if (status) {
+ netdev_warn(netdev, "%s: submit rx urb failed: %d\n",
+ __func__, status);
+ return status;
+ }
+ }
+
+ status = usb_submit_urb(priv->int_urb, GFP_KERNEL);
+ if (status) {
+ netdev_warn(netdev, "%s: submit int urb failed: %d\n",
+ __func__, status);
+ return status;
+ }
+
+ return 0;
+}
+
+static int f81604_start(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int status;
+ u8 mode;
+ u8 tmp;
+
+ f81604_unregister_urbs(netdev);
+
+ 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;
+
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id, 0x80,
+ mode);
+ if (status)
+ return status;
+
+ /* set reset mode */
+ status = f81604_set_reset_mode(netdev);
+ if (status)
+ return status;
+
+ status = f81604_chipset_init(netdev);
+ if (status)
+ return status;
+
+ /* Clear error counters and error code capture */
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_TXERR, 0);
+ if (status)
+ return status;
+
+ status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_RXERR, 0);
+ if (status)
+ return status;
+
+ /* Read clear for ECC/ALC/IR register */
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_ECC, &tmp);
+ if (status)
+ return status;
+
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_ALC, &tmp);
+ if (status)
+ return status;
+
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_IR, &tmp);
+ if (status)
+ return status;
+
+ status = f81604_register_urbs(netdev);
+ if (status)
+ return status;
+
+ return f81604_set_normal_mode(netdev);
+}
+
+static int f81604_set_bittiming(struct net_device *dev)
+{
+ struct f81604_port_priv *priv = netdev_priv(dev);
+ struct can_bittiming *bt;
+ int status = 0;
+ u8 btr0, btr1;
+
+ bt = &priv->can.bittiming;
+ btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
+ btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
+ (((bt->phase_seg2 - 1) & 0x7) << 4);
+
+ if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+ btr1 |= 0x80;
+
+ netdev_info(dev, "BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
+
+ status = f81604_set_sja1000_register(priv->dev, dev->dev_id,
+ SJA1000_BTR0, btr0);
+ if (status) {
+ netdev_warn(dev, "%s: Set BTR0 failed: %d\n", __func__,
+ status);
+ return status;
+ }
+
+ status = f81604_set_sja1000_register(priv->dev, dev->dev_id,
+ SJA1000_BTR1, btr1);
+ if (status) {
+ netdev_warn(dev, "%s: Set BTR1 failed: %d\n", __func__,
+ status);
+ return status;
+ }
+
+ return 0;
+}
+
+static int f81604_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+ int err;
+
+ switch (mode) {
+ case CAN_MODE_START:
+ err = f81604_start(netdev);
+ if (!err && netif_queue_stopped(netdev))
+ netif_wake_queue(netdev);
+ break;
+
+ default:
+ err = -EOPNOTSUPP;
+ }
+
+ return err;
+}
+
+static void f81604_process_rx_packet(struct urb *urb)
+{
+ struct net_device_stats *stats;
+ struct net_device *netdev;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ u8 *data;
+ u8 *ptr;
+ int i;
+ int count;
+
+ netdev = urb->context;
+ stats = &netdev->stats;
+ data = urb->transfer_buffer;
+
+ if (urb->actual_length % 14) {
+ netdev_warn(netdev, "actual_length %% 14 != 0 (%d)\n",
+ urb->actual_length);
+ } else if (!urb->actual_length) {
+ netdev_warn(netdev, "actual_length = 0 (%d)\n",
+ urb->actual_length);
+ }
+
+ count = urb->actual_length / F81604_DATA_SIZE;
+
+ for (i = 0; i < count; ++i) {
+ ptr = &data[i * F81604_DATA_SIZE];
+
+ if (ptr[F81604_CMD_OFFSET] != F81604_CMD_DATA)
+ continue;
+
+ skb = alloc_can_skb(netdev, &cf);
+ if (!skb) {
+ netdev_warn(netdev, "%s: not enough memory", __func__);
+ continue;
+ }
+
+ cf->can_dlc = can_cc_dlc2len(ptr[F81604_DLC_OFFSET] & 0xF);
+
+ if (ptr[F81604_DLC_OFFSET] & F81604_EFF_BIT) {
+ cf->can_id = (ptr[F81604_ID1_OFFSET] << 21) |
+ (ptr[F81604_ID2_OFFSET] << 13) |
+ (ptr[F81604_ID3_OFFSET] << 5) |
+ (ptr[F81604_ID4_OFFSET] >> 3);
+ cf->can_id |= CAN_EFF_FLAG;
+ } else {
+ cf->can_id = (ptr[F81604_ID1_OFFSET] << 3) |
+ (ptr[F81604_ID2_OFFSET] >> 5);
+ }
+
+ if (ptr[F81604_DLC_OFFSET] & F81604_RTR_BIT) {
+ cf->can_id |= CAN_RTR_FLAG;
+ } else if (ptr[F81604_DLC_OFFSET] & F81604_EFF_BIT) {
+ memcpy(cf->data, &ptr[F81604_EFF_DATA_OFFSET],
+ cf->can_dlc);
+ } else {
+ memcpy(cf->data, &ptr[F81604_SFF_DATA_OFFSET],
+ cf->can_dlc);
+ }
+
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+ netif_rx(skb);
+ }
+}
+
+static void f81604_read_bulk_callback(struct urb *urb)
+{
+ struct net_device *netdev;
+ int status;
+ u8 *data;
+
+ netdev = urb->context;
+ data = urb->transfer_buffer;
+
+ if (!netif_device_present(netdev))
+ return;
+
+ switch (urb->status) {
+ case 0: /* success */
+ break;
+
+ case -ENOENT:
+ case -EPIPE:
+ case -EPROTO:
+ case -ESHUTDOWN:
+ netdev_info(netdev, "%s: URB aborted (%d)\n", __func__,
+ urb->status);
+ return;
+
+ default:
+ netdev_info(netdev, "%s: URB aborted (%d)\n", __func__,
+ urb->status);
+ goto resubmit_urb;
+ }
+
+ switch (data[F81604_CMD_OFFSET]) {
+ case F81604_CMD_DATA:
+ f81604_process_rx_packet(urb);
+ break;
+ default:
+ netdev_err(netdev, "unknown header: %x, len: %d\n",
+ data[F81604_CMD_OFFSET], urb->actual_length);
+ break;
+ }
+
+resubmit_urb:
+ status = usb_submit_urb(urb, GFP_ATOMIC);
+ if (status == -ENODEV) {
+ netif_device_detach(netdev);
+ } else if (status) {
+ netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
+ status);
+ }
+}
+
+static void f81604_write_bulk_callback(struct urb *urb)
+{
+ struct f81604_port_priv *priv;
+ struct net_device *netdev;
+ int r;
+
+ netdev = urb->context;
+ priv = netdev_priv(netdev);
+
+ if (!netif_device_present(netdev))
+ return;
+
+ switch (urb->status) {
+ case 0: /* success */
+ break;
+
+ case -ENOENT:
+ case -EPIPE:
+ case -EPROTO:
+ case -ESHUTDOWN:
+ default:
+ netdev_info(netdev, "Tx URB error (%d)\n", urb->status);
+ return;
+ }
+
+ r = can_get_echo_skb(netdev, 0, NULL);
+ if (r)
+ netdev_warn(netdev, "can_get_echo_skb() failed: %d\n", r);
+}
+
+static void f81604_handle_clear_overrun_work(struct work_struct *work)
+{
+ struct f81604_port_priv *priv;
+ struct net_device *netdev;
+
+ priv = container_of(work, struct f81604_port_priv,
+ handle_clear_overrun_work);
+ netdev = priv->netdev;
+
+ f81604_set_sja1000_register(priv->dev, netdev->dev_id, SJA1000_CMR,
+ CMD_CDO);
+}
+
+static void f81604_handle_clear_reg_work(struct work_struct *work)
+{
+ struct f81604_port_priv *priv;
+ struct net_device *netdev;
+ bool clear_ecc, clear_alc;
+ unsigned long flags;
+ u8 tmp;
+
+ priv = container_of(work, struct f81604_port_priv,
+ handle_clear_reg_work);
+ netdev = priv->netdev;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ clear_alc = priv->need_clear_alc;
+ clear_ecc = priv->need_clear_ecc;
+ priv->need_clear_alc = false;
+ priv->need_clear_ecc = false;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ if (clear_alc) {
+ f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_ALC, &tmp);
+ }
+
+ if (clear_ecc) {
+ f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_ECC, &tmp);
+ }
+}
+
+static void f81604_read_int_callback(struct urb *urb)
+{
+ struct net_device_stats *stats;
+ struct f81604_port_priv *priv;
+ struct net_device *netdev;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ enum can_state can_state;
+ enum can_state rx_state, tx_state;
+ u8 *data;
+ u8 sr, isrc, alc, ecc;
+ u8 rxerr, txerr;
+ unsigned long flags;
+ int status;
+
+ netdev = urb->context;
+ priv = netdev_priv(netdev);
+ stats = &netdev->stats;
+ can_state = priv->can.state;
+ data = urb->transfer_buffer;
+
+ if (!netif_device_present(netdev))
+ return;
+
+ switch (urb->status) {
+ case 0: /* success */
+ break;
+
+ case -ENOENT:
+ case -EPIPE:
+ case -EPROTO:
+ case -ESHUTDOWN:
+ netdev_info(netdev, "%s: Int URB aborted (%d)\n", __func__,
+ urb->status);
+ return;
+
+ default:
+ netdev_info(netdev, "%s: Int URB aborted (%d)\n", __func__,
+ urb->status);
+ goto resubmit_urb;
+ }
+
+ /* Int EP Read data format: SR/IR/IER/ALC/ECC/EWLR/RXERR/TXERR/VAL
+ * Note: ALC/ECC will not auto clear by here, must to read clear by
+ * read register (via handle_clear_reg_work).
+ */
+ sr = data[0];
+ isrc = data[1];
+ alc = data[3];
+ ecc = data[4];
+ rxerr = data[6];
+ txerr = data[7];
+
+ /* handle can bus errors */
+ if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
+ skb = alloc_can_err_skb(netdev, &cf);
+ if (!skb) {
+ netdev_warn(netdev,
+ "no memory to alloc_can_err_skb\n");
+ goto resubmit_urb;
+ }
+
+ cf->data[6] = txerr;
+ cf->data[7] = rxerr;
+
+ if (isrc & IRQ_DOI) {
+ /* data overrun interrupt */
+ netdev_dbg(netdev, "data overrun interrupt\n");
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+ stats->rx_over_errors++;
+ stats->rx_errors++;
+
+ schedule_work(&priv->handle_clear_overrun_work);
+ }
+
+ if (isrc & IRQ_EI) {
+ /* error warning interrupt */
+ netdev_dbg(netdev, "error warning interrupt\n");
+
+ if (sr & SR_BS)
+ can_state = CAN_STATE_BUS_OFF;
+ else if (sr & SR_ES)
+ can_state = CAN_STATE_ERROR_WARNING;
+ else
+ can_state = CAN_STATE_ERROR_ACTIVE;
+ }
+
+ if (isrc & IRQ_BEI) {
+ /* bus error interrupt */
+ netdev_dbg(netdev, "bus error interrupt\n");
+
+ priv->can.can_stats.bus_error++;
+ stats->rx_errors++;
+
+ cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+ /* set error type */
+ switch (ecc & ECC_MASK) {
+ case ECC_BIT:
+ cf->data[2] |= CAN_ERR_PROT_BIT;
+ break;
+ case ECC_FORM:
+ cf->data[2] |= CAN_ERR_PROT_FORM;
+ break;
+ case ECC_STUFF:
+ cf->data[2] |= CAN_ERR_PROT_STUFF;
+ break;
+ default:
+ break;
+ }
+
+ /* set error location */
+ cf->data[3] = ecc & ECC_SEG;
+
+ /* Error occurred during transmission? */
+ if ((ecc & ECC_DIR) == 0)
+ cf->data[2] |= CAN_ERR_PROT_TX;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->need_clear_ecc = true;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ schedule_work(&priv->handle_clear_reg_work);
+ }
+
+ if (isrc & 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: %x\n",
+ can_state);
+ }
+
+ if (isrc & IRQ_ALI) {
+ /* arbitration lost interrupt */
+ netdev_dbg(netdev, "arbitration lost interrupt\n");
+
+ priv->can.can_stats.arbitration_lost++;
+ stats->tx_errors++;
+ cf->can_id |= CAN_ERR_LOSTARB;
+ cf->data[0] = alc & 0x1f;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->need_clear_alc = true;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ schedule_work(&priv->handle_clear_reg_work);
+ }
+
+ if (can_state != priv->can.state) {
+ tx_state = txerr >= rxerr ? can_state : 0;
+ rx_state = txerr <= rxerr ? can_state : 0;
+
+ can_change_state(netdev, cf, tx_state, rx_state);
+
+ if (can_state == CAN_STATE_BUS_OFF)
+ can_bus_off(netdev);
+ }
+
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+ netif_rx(skb);
+ }
+
+ /* handle TX */
+ if ((isrc & IRQ_TI) && can_state != CAN_STATE_BUS_OFF) {
+ /* transmission buffer released */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
+ !(sr & 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);
+ }
+
+resubmit_urb:
+ status = usb_submit_urb(urb, GFP_ATOMIC);
+ if (status) {
+ netdev_err(netdev,
+ "%s: failed resubmitting int bulk urb: %d\n",
+ __func__, status);
+
+ if (status == -ENODEV)
+ netif_device_detach(netdev);
+ }
+}
+
+static netdev_tx_t f81604_start_xmit(struct sk_buff *skb,
+ struct net_device *netdev)
+{
+ struct net_device_stats *stats;
+ struct f81604_port_priv *priv;
+ struct can_frame *cf;
+ int status;
+ u8 *ptr;
+ u32 id;
+
+ priv = netdev_priv(netdev);
+ cf = (struct can_frame *)skb->data;
+ stats = &netdev->stats;
+
+ if (can_dropped_invalid_skb(netdev, skb))
+ return NETDEV_TX_OK;
+
+ netif_stop_queue(netdev);
+
+ ptr = priv->bulk_write_buffer;
+ memset(ptr, 0, F81604_DATA_SIZE);
+
+ ptr[0] = F81604_CMD_DATA;
+ ptr[1] = min_t(u8, cf->can_dlc & 0xf, 8);
+
+ if (cf->can_id & CAN_EFF_FLAG) {
+ id = (cf->can_id & CAN_ERR_MASK) << 3;
+ ptr[1] |= F81604_EFF_BIT;
+ ptr[2] = (id >> 24) & 0xff;
+ ptr[3] = (id >> 16) & 0xff;
+ ptr[4] = (id >> 8) & 0xff;
+ ptr[5] = (id >> 0) & 0xff;
+ memcpy(&ptr[6], cf->data, ptr[1]);
+ } else {
+ id = (cf->can_id & CAN_ERR_MASK) << 5;
+ ptr[2] = (id >> 8) & 0xff;
+ ptr[3] = (id >> 0) & 0xff;
+ memcpy(&ptr[4], cf->data, ptr[1]);
+ }
+
+ if (cf->can_id & CAN_RTR_FLAG)
+ ptr[1] |= F81604_RTR_BIT;
+
+ can_put_echo_skb(skb, netdev, 0, 0);
+
+ status = usb_submit_urb(priv->write_urb, GFP_ATOMIC);
+ if (status) {
+ netdev_err(netdev, "%s: failed resubmitting tx bulk urb: %d\n",
+ __func__, status);
+
+ can_free_echo_skb(netdev, 0, NULL);
+ stats->tx_dropped++;
+
+ if (status == -ENODEV)
+ netif_device_detach(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);
+ int status;
+ u8 txerr;
+ u8 rxerr;
+
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_TXERR, &txerr);
+ if (status)
+ return status;
+
+ status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
+ SJA1000_RXERR, &rxerr);
+ if (status)
+ return status;
+
+ bec->txerr = txerr;
+ bec->rxerr = rxerr;
+
+ return 0;
+}
+
+static void f81604_remove_urbs(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+ int i;
+
+ for (i = 0; i < F81604_MAX_RX_URBS; ++i)
+ usb_free_urb(priv->read_urb[i]);
+
+ usb_free_urb(priv->write_urb);
+ usb_free_urb(priv->int_urb);
+}
+
+static int f81604_prepare_urbs(struct net_device *netdev)
+{
+ static u8 bulk_in_addr[F81604_MAX_DEV] = { 0x82, 0x84 };
+ static u8 bulk_out_addr[F81604_MAX_DEV] = { 0x01, 0x03 };
+ static u8 int_in_addr[F81604_MAX_DEV] = { 0x81, 0x83 };
+ struct f81604_port_priv *priv;
+ int id;
+ int i;
+
+ priv = netdev_priv(netdev);
+ id = netdev->dev_id;
+
+ /* initialize to NULL for error recovery */
+ for (i = 0; i < F81604_MAX_RX_URBS; ++i)
+ priv->read_urb[i] = NULL;
+
+ priv->write_urb = NULL;
+ priv->int_urb = NULL;
+
+ for (i = 0; i < F81604_MAX_RX_URBS; ++i) {
+ priv->read_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
+ if (!priv->read_urb[i])
+ goto error;
+
+ usb_fill_bulk_urb(priv->read_urb[i], priv->dev,
+ usb_rcvbulkpipe(priv->dev, bulk_in_addr[id]),
+ priv->bulk_read_buffer[i], F81604_BULK_SIZE,
+ f81604_read_bulk_callback, netdev);
+ }
+
+ priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!priv->write_urb)
+ goto error;
+
+ usb_fill_bulk_urb(priv->write_urb, priv->dev,
+ usb_sndbulkpipe(priv->dev, bulk_out_addr[id]),
+ priv->bulk_write_buffer, F81604_DATA_SIZE,
+ f81604_write_bulk_callback, netdev);
+
+ priv->int_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!priv->int_urb)
+ goto error;
+
+ usb_fill_int_urb(priv->int_urb, priv->dev,
+ usb_rcvintpipe(priv->dev, int_in_addr[id]),
+ priv->int_read_buffer, F81604_INT_SIZE,
+ f81604_read_int_callback, netdev, 1);
+
+ return 0;
+
+error:
+ f81604_remove_urbs(netdev);
+ return -ENOMEM;
+}
+
+/* Open USB device */
+static int f81604_open(struct net_device *netdev)
+{
+ int err;
+
+ err = f81604_prepare_urbs(netdev);
+ if (err)
+ return err;
+
+ err = open_candev(netdev);
+ if (err)
+ goto remove_urbs;
+
+ err = f81604_start(netdev);
+ if (err)
+ goto start_failed;
+
+ netif_start_queue(netdev);
+ return 0;
+
+start_failed:
+ if (err == -ENODEV)
+ netif_device_detach(netdev);
+
+ close_candev(netdev);
+
+remove_urbs:
+ f81604_remove_urbs(netdev);
+
+ return err;
+}
+
+/* Close USB device */
+static int f81604_close(struct net_device *netdev)
+{
+ struct f81604_port_priv *priv = netdev_priv(netdev);
+
+ f81604_set_reset_mode(netdev);
+
+ netif_stop_queue(netdev);
+ cancel_work_sync(&priv->handle_clear_overrun_work);
+ cancel_work_sync(&priv->handle_clear_reg_work);
+ close_candev(netdev);
+
+ f81604_unregister_urbs(netdev);
+ f81604_remove_urbs(netdev);
+
+ 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 = "f81604",
+ .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);
+ int i;
+
+ for (i = 0; i < F81604_MAX_DEV; ++i) {
+ if (!priv->netdev[i])
+ continue;
+
+ unregister_netdev(priv->netdev[i]);
+ free_candev(priv->netdev[i]);
+ }
+}
+
+static int f81604_probe(struct usb_interface *intf,
+ const struct usb_device_id *id)
+{
+ struct f81604_port_priv *port_priv;
+ struct net_device *netdev;
+ struct f81604_priv *priv;
+ struct usb_device *dev;
+ int i, err;
+
+ dev_info(&intf->dev, "Detected Fintek F81604 device.\n");
+ dev_info(&intf->dev,
+ "Please download newest driver from Fintek website\n");
+ dev_info(&intf->dev, "if you want to use customized functions.\n");
+
+ dev = interface_to_usbdev(intf);
+
+ priv = devm_kzalloc(&intf->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ usb_set_intfdata(intf, priv);
+
+ for (i = 0; i < F81604_MAX_DEV; ++i) {
+ netdev = alloc_candev(sizeof(*port_priv), 1);
+ if (!netdev) {
+ dev_err(&intf->dev, "Couldn't alloc candev: %d\n", i);
+ err = -ENOMEM;
+
+ goto failure_cleanup;
+ }
+
+ port_priv = netdev_priv(netdev);
+ netdev->dev_id = i;
+
+ spin_lock_init(&port_priv->lock);
+ INIT_WORK(&port_priv->handle_clear_overrun_work,
+ f81604_handle_clear_overrun_work);
+ INIT_WORK(&port_priv->handle_clear_reg_work,
+ f81604_handle_clear_reg_work);
+
+ port_priv->intf = intf;
+ port_priv->dev = dev;
+ port_priv->ocr = OCR_TX0_PUSHPULL | OCR_TX1_PUSHPULL;
+ port_priv->cdr = CDR_CBP;
+ port_priv->can.state = CAN_STATE_STOPPED;
+ port_priv->can.clock.freq = 24000000 / 2;
+
+ 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_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;
+
+ port_priv->can.ctrlmode_supported |= CAN_CTRLMODE_PRESUME_ACK;
+ netdev->netdev_ops = &f81604_netdev_ops;
+ netdev->flags |= IFF_ECHO;
+
+ SET_NETDEV_DEV(netdev, &intf->dev);
+
+ err = register_candev(netdev);
+ if (err) {
+ netdev_err(netdev,
+ "couldn't register CAN device: %d\n", err);
+ free_candev(netdev);
+
+ goto failure_cleanup;
+ }
+
+ port_priv->netdev = netdev;
+ 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 err;
+}
+
+static struct usb_driver f81604_driver = {
+ .name = "f81604",
+ .probe = f81604_probe,
+ .disconnect = f81604_disconnect,
+ .id_table = f81604_table,
+};
+
+module_usb_driver(f81604_driver);
+
+MODULE_AUTHOR("Ji-Ze Hong (Peter Hong) <[email protected]>");
+MODULE_DESCRIPTION("Fintek F81604 USB to 2xCANBUS");
+MODULE_LICENSE("GPL");
--
2.17.1



2023-03-17 13:16:15

by Michal Swiatkowski

[permalink] [raw]
Subject: Re: [PATCH] can: usb: f81604: add Fintek F81604 support

On Fri, Mar 17, 2023 at 05:33:52PM +0800, Ji-Ze Hong (Peter Hong) wrote:
> This patch add support for Fintek USB to 2CAN controller support.
>
> Signed-off-by: Ji-Ze Hong (Peter Hong) <[email protected]>
> ---
> drivers/net/can/usb/Kconfig | 9 +
> drivers/net/can/usb/Makefile | 1 +
> drivers/net/can/usb/f81604.c | 1215 ++++++++++++++++++++++++++++++++++
> 3 files changed, 1225 insertions(+)
> create mode 100644 drivers/net/can/usb/f81604.c
>
> diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig
> index 445504ababce..381547939c39 100644
> --- a/drivers/net/can/usb/Kconfig
> +++ b/drivers/net/can/usb/Kconfig
> @@ -147,4 +147,13 @@ config CAN_UCAN
> from Theobroma Systems like the A31-ÂľQ7 and the RK3399-Q7
> (https://www.theobroma-systems.com/rk3399-q7)
>
Hi,

I am not familiar with CAN, so only style review :)

> +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).
> +
> + (see also https://www.fintek.com.tw).
> +
> endmenu
> diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile
> index 1ea16be5743b..9de0305a5cce 100644
> --- a/drivers/net/can/usb/Makefile
> +++ b/drivers/net/can/usb/Makefile
> @@ -12,3 +12,4 @@ obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb/
> obj-$(CONFIG_CAN_MCBA_USB) += mcba_usb.o
> obj-$(CONFIG_CAN_PEAK_USB) += peak_usb/
> obj-$(CONFIG_CAN_UCAN) += ucan.o
> +obj-$(CONFIG_CAN_F81604) += f81604.o
> diff --git a/drivers/net/can/usb/f81604.c b/drivers/net/can/usb/f81604.c
> new file mode 100644
> index 000000000000..166f5789247e
> --- /dev/null
> +++ b/drivers/net/can/usb/f81604.c
> @@ -0,0 +1,1215 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Fintek F81604 USB-to-2CAN controller driver.
> + *
> + * Copyright (C) 2023 Ji-Ze Hong (Peter Hong) <[email protected]>
> + */
> +#include <linux/netdevice.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>
> +
> +/* vendor and product id */
> +#define F81604_VENDOR_ID 0x2c42
> +#define F81604_PRODUCT_ID 0x1709
> +#define F81604_MAX_DEV 2
> +
> +#define F81604_USB_MAX_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_OFFSET 0x00
> +#define F81604_CMD_DATA 0x00
> +
> +#define F81604_DLC_OFFSET 0x01
> +#define F81604_LEN_MASK 0x0f
> +#define F81604_EFF_BIT BIT(7)
> +#define F81604_RTR_BIT BIT(6)
> +
> +#define F81604_ID1_OFFSET 0x02
> +#define F81604_ID2_OFFSET 0x03
> +#define F81604_ID3_OFFSET 0x04
> +#define F81604_ID4_OFFSET 0x05
> +
> +#define F81604_SFF_DATA_OFFSET 0x04
> +#define F81604_EFF_DATA_OFFSET 0x06
> +
> +/* device setting */
> +#define F81604_TX_ONESHOT (0x03 << 3)
> +#define F81604_TX_NORMAL (0x01 << 3)
> +#define F81604_RX_AUTO_RELEASE_BUF (0x01 << 1)
> +#define F81604_INT_WHEN_CHANGE (0x01 << 0)
> +
> +/* SJA1000 registers - manual section 6.4 (Pelican Mode) */
> +#define SJA1000_MOD 0x00
> +#define SJA1000_CMR 0x01
> +#define SJA1000_IR 0x03
> +#define SJA1000_IER 0x04
> +#define SJA1000_ALC 0x0B
> +#define SJA1000_ECC 0x0C
> +#define SJA1000_RXERR 0x0E
> +#define SJA1000_TXERR 0x0F
> +#define SJA1000_ACCC0 0x10
> +#define SJA1000_ACCC1 0x11
> +#define SJA1000_ACCC2 0x12
> +#define SJA1000_ACCC3 0x13
> +#define SJA1000_ACCM0 0x14
> +#define SJA1000_ACCM1 0x15
> +#define SJA1000_ACCM2 0x16
> +#define SJA1000_ACCM3 0x17
> +
> +/* Common registers - manual section 6.5 */
> +#define SJA1000_BTR0 0x06
> +#define SJA1000_BTR1 0x07
> +#define SJA1000_OCR 0x08
> +#define SJA1000_CDR 0x1F
> +
> +#define SJA1000_FI 0x10
> +#define SJA1000_SFF_BUF 0x13
> +#define SJA1000_EFF_BUF 0x15
> +
> +#define SJA1000_FI_FF 0x80
> +#define SJA1000_FI_RTR 0x40
> +
> +#define SJA1000_ID1 0x11
> +#define SJA1000_ID2 0x12
> +#define SJA1000_ID3 0x13
> +#define SJA1000_ID4 0x14
> +
> +/* mode register */
> +#define MOD_RM 0x01
> +#define MOD_LOM 0x02
> +#define MOD_STM 0x04
> +
> +/* commands */
> +#define CMD_CDO 0x08
> +
> +/* interrupt sources */
> +#define IRQ_BEI 0x80
> +#define IRQ_ALI 0x40
> +#define IRQ_EPI 0x20
> +#define IRQ_DOI 0x08
> +#define IRQ_EI 0x04
> +#define IRQ_TI 0x02
> +#define IRQ_RI 0x01
> +#define IRQ_ALL 0xFF
> +#define IRQ_OFF 0x00
> +
> +/* status register content */
> +#define SR_BS 0x80
> +#define SR_ES 0x40
> +#define SR_TS 0x20
> +#define SR_RS 0x10
> +#define SR_TCS 0x08
> +#define SR_TBS 0x04
> +#define SR_DOS 0x02
> +#define SR_RBS 0x01
> +
> +/* ECC register */
> +#define ECC_SEG 0x1F
> +#define ECC_DIR 0x20
> +#define ECC_BIT 0x00
> +#define ECC_FORM 0x40
> +#define ECC_STUFF 0x80
> +#define ECC_MASK 0xc0
> +
> +/* 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);
> +
> +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;
> +
> + /* For synchronize need_clear_alc/need_clear_ecc in worker & interrupt
> + * callback.
> + */
> + spinlock_t lock;
> + bool need_clear_alc;
> + bool need_clear_ecc;
> +
> + struct work_struct handle_clear_reg_work;
> + struct work_struct handle_clear_overrun_work;
> +
> + struct usb_device *dev;
> + struct usb_interface *intf;
> +
> + struct urb *int_urb;
> + u8 int_read_buffer[F81604_INT_SIZE];
> +
> + struct urb *read_urb[F81604_MAX_RX_URBS];
> + u8 bulk_read_buffer[F81604_MAX_RX_URBS][F81604_BULK_SIZE];
> +
> + struct urb *write_urb;
> + u8 bulk_write_buffer[F81604_DATA_SIZE];
> +
> + u8 ocr;
> + u8 cdr;
> +};
> +
> +static int f81604_set_register(struct usb_device *dev, u16 reg, u8 data)
> +{
> + size_t count = F81604_USB_MAX_RETRY;
> + int status;
> +
> + while (count--) {
> + status = usb_control_msg_send(dev, 0, F81604_SET_GET_REGISTER,
> + USB_TYPE_VENDOR | USB_DIR_OUT, 0,
> + reg, &data, sizeof(u8),
> + F81604_USB_TIMEOUT, GFP_KERNEL);
> + if (!status)
> + break;
> + }
> +
> + if (status) {
> + dev_err(&dev->dev, "%s: reg: %x data: %x failed: %d\n",
> + __func__, reg, data, status);
> + }
The { and } aren't needed as inside if is only one line.

> +
> + return status;
> +}
> +
> +static int f81604_get_register(struct usb_device *dev, u16 reg, u8 *data)
> +{
> + size_t count = F81604_USB_MAX_RETRY;
> + int status;
> +
> + while (count--) {
> + status = usb_control_msg_recv(dev, 0, F81604_SET_GET_REGISTER,
> + USB_TYPE_VENDOR | USB_DIR_IN, 0,
> + reg, data, sizeof(u8),
> + F81604_USB_TIMEOUT, GFP_KERNEL);
> + if (!status)
> + break;
> + }
> +
> + if (status < 0) {
> + dev_err(&dev->dev, "%s: reg: %x failed: %d\n", __func__, reg,
> + status);
> + }
the same, and also if (status) is more preferable I think, and You also used it
previously.

> +
> + return status;
> +}
> +
> +static int f81604_set_sja1000_register(struct usb_device *dev, u8 port,
> + u16 reg, u8 data)
> +{
> + int real_reg;
> +
> + real_reg = reg + F81604_PORT_OFFSET * port + F81604_PORT_OFFSET;
> + return f81604_set_register(dev, real_reg, data);
> +}
> +
> +static int f81604_get_sja1000_register(struct usb_device *dev, u8 port,
> + u16 reg, u8 *data)
> +{
> + int real_reg;
> +
> + real_reg = reg + F81604_PORT_OFFSET * port + F81604_PORT_OFFSET;
> + return f81604_get_register(dev, real_reg, data);
> +}
> +
> +static int f81604_set_reset_mode(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int status, i;
> + u8 tmp;
> +
> + /* disable interrupts */
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_IER, IRQ_OFF);
> + if (status)
> + return status;
> +
> + for (i = 0; i < 100; i++) {
Why 100? Maybe define to name it somehow

> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_MOD, &tmp);
> + if (status)
> + return status;
> +
> + /* check reset bit */
> + if (tmp & MOD_RM) {
> + priv->can.state = CAN_STATE_STOPPED;
> + return 0;
> + }
> +
> + /* reset chip */
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_MOD, MOD_RM);
> + if (status)
> + return status;
> + }
> +
> + netdev_err(netdev, "setting SJA1000 into reset mode failed!\n");
> + return -EINVAL;
> +}
> +
> +static int f81604_set_normal_mode(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int status, i;
> + u8 mod_reg_val = 0x00;
RCT, mod_reg should be one line above

> + u8 ier = 0;
> + u8 tmp;
> +
> + for (i = 0; i < 100; i++) {
> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_MOD, &tmp);
> + if (status)
> + return status;
> +
> + /* check reset bit */
> + if ((tmp & MOD_RM) == 0) {
> + priv->can.state = CAN_STATE_ERROR_ACTIVE;
> + /* enable interrupts, RI handled by bulk-in */
> + if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
> + ier = IRQ_ALL & ~IRQ_RI;
> + else
> + ier = IRQ_ALL & ~(IRQ_RI | IRQ_BEI);
> +
> + status = f81604_set_sja1000_register(priv->dev,
> + netdev->dev_id,
> + SJA1000_IER,
> + ier);
> +
> + return status;
> + }
> +
> + /* set chip to normal mode */
> + if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
> + mod_reg_val |= MOD_LOM;
> + if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK)
> + mod_reg_val |= MOD_STM;
> +
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_MOD, mod_reg_val);
> + if (status)
> + return status;
> + }
> +
> + netdev_err(netdev, "setting SJA1000 into normal mode failed!\n");
> + return -EINVAL;
> +}
> +
> +static int f81604_chipset_init(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int status;
> + int i;
> +
> + /* set clock divider and output control register */
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_CDR,
> + priv->cdr | CDR_PELICAN);
> + if (status)
> + return status;
> +
> + /* set acceptance filter (accept all) */
> + for (i = 0; i < 4; ++i) {
4 is a number of filters?

> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_ACCC0 + i, 0);
> + if (status)
> + return status;
> + }
> +
> + for (i = 0; i < 4; ++i) {
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_ACCM0 + i, 0xFF);
> + if (status)
> + return status;
> + }
> +
> + return f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_OCR,
> + priv->ocr | OCR_MODE_NORMAL);
> +}
> +
> +static void f81604_unregister_urbs(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int i;
> +
> + usb_kill_urb(priv->write_urb);
> +
> + for (i = 0; i < F81604_MAX_RX_URBS; ++i)
> + usb_kill_urb(priv->read_urb[i]);
> +
> + usb_kill_urb(priv->int_urb);
> +}
> +
> +static int f81604_register_urbs(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int status, i;
> +
> + for (i = 0; i < F81604_MAX_RX_URBS; ++i) {
> + status = usb_submit_urb(priv->read_urb[i], GFP_KERNEL);
> + if (status) {
> + netdev_warn(netdev, "%s: submit rx urb failed: %d\n",
> + __func__, status);
> + return status;
Don't know usb subsytem, but shouldn't previously submitted urb be
killed?

> + }
> + }
> +
> + status = usb_submit_urb(priv->int_urb, GFP_KERNEL);
> + if (status) {
> + netdev_warn(netdev, "%s: submit int urb failed: %d\n",
> + __func__, status);
> + return status;
The same here

> + }
> +
> + return 0;
> +}
> +
> +static int f81604_start(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int status;
> + u8 mode;
> + u8 tmp;
> +
> + f81604_unregister_urbs(netdev);
> +
> + 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;
> +
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id, 0x80,
> + mode);
> + if (status)
> + return status;
> +
> + /* set reset mode */
> + status = f81604_set_reset_mode(netdev);
> + if (status)
> + return status;
> +
> + status = f81604_chipset_init(netdev);
> + if (status)
> + return status;
> +
> + /* Clear error counters and error code capture */
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_TXERR, 0);
> + if (status)
> + return status;
> +
> + status = f81604_set_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_RXERR, 0);
> + if (status)
> + return status;
> +
> + /* Read clear for ECC/ALC/IR register */
> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_ECC, &tmp);
> + if (status)
> + return status;
> +
> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_ALC, &tmp);
> + if (status)
> + return status;
> +
> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_IR, &tmp);
> + if (status)
> + return status;
> +
> + status = f81604_register_urbs(netdev);
> + if (status)
> + return status;
> +
> + return f81604_set_normal_mode(netdev);
> +}
> +
> +static int f81604_set_bittiming(struct net_device *dev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(dev);
> + struct can_bittiming *bt;
> + int status = 0;
> + u8 btr0, btr1;
> +
> + bt = &priv->can.bittiming;
> + btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
> + btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
> + (((bt->phase_seg2 - 1) & 0x7) << 4);
> +
> + if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
> + btr1 |= 0x80;
> +
> + netdev_info(dev, "BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
> +
> + status = f81604_set_sja1000_register(priv->dev, dev->dev_id,
> + SJA1000_BTR0, btr0);
> + if (status) {
> + netdev_warn(dev, "%s: Set BTR0 failed: %d\n", __func__,
> + status);
> + return status;
> + }
> +
> + status = f81604_set_sja1000_register(priv->dev, dev->dev_id,
> + SJA1000_BTR1, btr1);
> + if (status) {
> + netdev_warn(dev, "%s: Set BTR1 failed: %d\n", __func__,
> + status);
> + return status;
> + }
> +
> + return 0;
> +}
> +
> +static int f81604_set_mode(struct net_device *netdev, enum can_mode mode)
> +{
> + int err;
> +
> + switch (mode) {
> + case CAN_MODE_START:
> + err = f81604_start(netdev);
> + if (!err && netif_queue_stopped(netdev))
> + netif_wake_queue(netdev);
> + break;
> +
> + default:
> + err = -EOPNOTSUPP;
> + }
> +
> + return err;
> +}
> +
> +static void f81604_process_rx_packet(struct urb *urb)
> +{
> + struct net_device_stats *stats;
> + struct net_device *netdev;
> + struct can_frame *cf;
> + struct sk_buff *skb;
> + u8 *data;
> + u8 *ptr;
> + int i;
> + int count;
RCT

> +
> + netdev = urb->context;
> + stats = &netdev->stats;
> + data = urb->transfer_buffer;
netdev and data can be set in declaration

> +
> + if (urb->actual_length % 14) {
> + netdev_warn(netdev, "actual_length %% 14 != 0 (%d)\n",
> + urb->actual_length);
> + } else if (!urb->actual_length) {
> + netdev_warn(netdev, "actual_length = 0 (%d)\n",
> + urb->actual_length);
> + }
if ()

else ()

{} aren't needed here

> +
> + count = urb->actual_length / F81604_DATA_SIZE;
> +
> + for (i = 0; i < count; ++i) {
> + ptr = &data[i * F81604_DATA_SIZE];
> +
> + if (ptr[F81604_CMD_OFFSET] != F81604_CMD_DATA)
> + continue;
> +
> + skb = alloc_can_skb(netdev, &cf);
> + if (!skb) {
> + netdev_warn(netdev, "%s: not enough memory", __func__);
> + continue;
> + }
> +
> + cf->can_dlc = can_cc_dlc2len(ptr[F81604_DLC_OFFSET] & 0xF);
> +
> + if (ptr[F81604_DLC_OFFSET] & F81604_EFF_BIT) {
> + cf->can_id = (ptr[F81604_ID1_OFFSET] << 21) |
> + (ptr[F81604_ID2_OFFSET] << 13) |
> + (ptr[F81604_ID3_OFFSET] << 5) |
> + (ptr[F81604_ID4_OFFSET] >> 3);
> + cf->can_id |= CAN_EFF_FLAG;
> + } else {
> + cf->can_id = (ptr[F81604_ID1_OFFSET] << 3) |
> + (ptr[F81604_ID2_OFFSET] >> 5);
> + }
> +
> + if (ptr[F81604_DLC_OFFSET] & F81604_RTR_BIT) {
> + cf->can_id |= CAN_RTR_FLAG;
> + } else if (ptr[F81604_DLC_OFFSET] & F81604_EFF_BIT) {
> + memcpy(cf->data, &ptr[F81604_EFF_DATA_OFFSET],
> + cf->can_dlc);
> + } else {
> + memcpy(cf->data, &ptr[F81604_SFF_DATA_OFFSET],
> + cf->can_dlc);
> + }
> +
> + stats->rx_packets++;
> + stats->rx_bytes += cf->can_dlc;
> + netif_rx(skb);
> + }
> +}
> +
> +static void f81604_read_bulk_callback(struct urb *urb)
> +{
> + struct net_device *netdev;
> + int status;
> + u8 *data;
> +
> + netdev = urb->context;
> + data = urb->transfer_buffer;
netdev and data can be set in declaration

> +
> + if (!netif_device_present(netdev))
> + return;
> +
> + switch (urb->status) {
> + case 0: /* success */
> + break;
> +
> + case -ENOENT:
> + case -EPIPE:
> + case -EPROTO:
> + case -ESHUTDOWN:
> + netdev_info(netdev, "%s: URB aborted (%d)\n", __func__,
> + urb->status);
> + return;
> +
> + default:
> + netdev_info(netdev, "%s: URB aborted (%d)\n", __func__,
> + urb->status);
> + goto resubmit_urb;
> + }
> +
> + switch (data[F81604_CMD_OFFSET]) {
> + case F81604_CMD_DATA:
> + f81604_process_rx_packet(urb);
> + break;
> + default:
> + netdev_err(netdev, "unknown header: %x, len: %d\n",
> + data[F81604_CMD_OFFSET], urb->actual_length);
> + break;
> + }
> +
> +resubmit_urb:
> + status = usb_submit_urb(urb, GFP_ATOMIC);
> + if (status == -ENODEV) {
> + netif_device_detach(netdev);
> + } else if (status) {
> + netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
> + status);
> + }
> +}
> +
> +static void f81604_write_bulk_callback(struct urb *urb)
> +{
> + struct f81604_port_priv *priv;
> + struct net_device *netdev;
> + int r;
> +
> + netdev = urb->context;
> + priv = netdev_priv(netdev);
Can be set in declaration

> +
> + if (!netif_device_present(netdev))
> + return;
> +
> + switch (urb->status) {
> + case 0: /* success */
> + break;
> +
> + case -ENOENT:
> + case -EPIPE:
> + case -EPROTO:
> + case -ESHUTDOWN:
> + default:
> + netdev_info(netdev, "Tx URB error (%d)\n", urb->status);
> + return;
> + }
if (urb->status) {
...
}

> +
> + r = can_get_echo_skb(netdev, 0, NULL);
> + if (r)
> + netdev_warn(netdev, "can_get_echo_skb() failed: %d\n", r);
> +}
> +
> +static void f81604_handle_clear_overrun_work(struct work_struct *work)
> +{
> + struct f81604_port_priv *priv;
> + struct net_device *netdev;
> +
> + priv = container_of(work, struct f81604_port_priv,
> + handle_clear_overrun_work);
> + netdev = priv->netdev;
> +
> + f81604_set_sja1000_register(priv->dev, netdev->dev_id, SJA1000_CMR,
> + CMD_CDO);
> +}
> +
> +static void f81604_handle_clear_reg_work(struct work_struct *work)
> +{
> + struct f81604_port_priv *priv;
> + struct net_device *netdev;
> + bool clear_ecc, clear_alc;
> + unsigned long flags;
> + u8 tmp;
> +
> + priv = container_of(work, struct f81604_port_priv,
> + handle_clear_reg_work);
> + netdev = priv->netdev;
> +
> + spin_lock_irqsave(&priv->lock, flags);
> + clear_alc = priv->need_clear_alc;
> + clear_ecc = priv->need_clear_ecc;
> + priv->need_clear_alc = false;
> + priv->need_clear_ecc = false;
> + spin_unlock_irqrestore(&priv->lock, flags);
> +
> + if (clear_alc) {
> + f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_ALC, &tmp);
> + }
> +
> + if (clear_ecc) {
> + f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_ECC, &tmp);
> + }
> +}
> +
> +static void f81604_read_int_callback(struct urb *urb)
> +{
> + struct net_device_stats *stats;
> + struct f81604_port_priv *priv;
> + struct net_device *netdev;
> + struct can_frame *cf;
> + struct sk_buff *skb;
> + enum can_state can_state;
> + enum can_state rx_state, tx_state;
> + u8 *data;
> + u8 sr, isrc, alc, ecc;
> + u8 rxerr, txerr;
> + unsigned long flags;
> + int status;
RCT

> +
> + netdev = urb->context;
> + priv = netdev_priv(netdev);
> + stats = &netdev->stats;
> + can_state = priv->can.state;
> + data = urb->transfer_buffer;
> +
> + if (!netif_device_present(netdev))
> + return;
> +
> + switch (urb->status) {
> + case 0: /* success */
> + break;
> +
> + case -ENOENT:
> + case -EPIPE:
> + case -EPROTO:
> + case -ESHUTDOWN:
> + netdev_info(netdev, "%s: Int URB aborted (%d)\n", __func__,
> + urb->status);
> + return;
> +
> + default:
> + netdev_info(netdev, "%s: Int URB aborted (%d)\n", __func__,
> + urb->status);
> + goto resubmit_urb;
> + }
> +
> + /* Int EP Read data format: SR/IR/IER/ALC/ECC/EWLR/RXERR/TXERR/VAL
> + * Note: ALC/ECC will not auto clear by here, must to read clear by
> + * read register (via handle_clear_reg_work).
> + */
> + sr = data[0];
> + isrc = data[1];
> + alc = data[3];
> + ecc = data[4];
> + rxerr = data[6];
> + txerr = data[7];
> +
> + /* handle can bus errors */
> + if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
> + skb = alloc_can_err_skb(netdev, &cf);
> + if (!skb) {
> + netdev_warn(netdev,
> + "no memory to alloc_can_err_skb\n");
> + goto resubmit_urb;
> + }
> +
> + cf->data[6] = txerr;
> + cf->data[7] = rxerr;
> +
> + if (isrc & IRQ_DOI) {
> + /* data overrun interrupt */
> + netdev_dbg(netdev, "data overrun interrupt\n");
> + cf->can_id |= CAN_ERR_CRTL;
> + cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
> + stats->rx_over_errors++;
> + stats->rx_errors++;
> +
> + schedule_work(&priv->handle_clear_overrun_work);
> + }
> +
> + if (isrc & IRQ_EI) {
> + /* error warning interrupt */
> + netdev_dbg(netdev, "error warning interrupt\n");
> +
> + if (sr & SR_BS)
> + can_state = CAN_STATE_BUS_OFF;
> + else if (sr & SR_ES)
> + can_state = CAN_STATE_ERROR_WARNING;
> + else
> + can_state = CAN_STATE_ERROR_ACTIVE;
> + }
> +
> + if (isrc & IRQ_BEI) {
> + /* bus error interrupt */
> + netdev_dbg(netdev, "bus error interrupt\n");
> +
> + priv->can.can_stats.bus_error++;
> + stats->rx_errors++;
> +
> + cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
> +
> + /* set error type */
> + switch (ecc & ECC_MASK) {
> + case ECC_BIT:
> + cf->data[2] |= CAN_ERR_PROT_BIT;
> + break;
> + case ECC_FORM:
> + cf->data[2] |= CAN_ERR_PROT_FORM;
> + break;
> + case ECC_STUFF:
> + cf->data[2] |= CAN_ERR_PROT_STUFF;
> + break;
> + default:
> + break;
> + }
> +
> + /* set error location */
> + cf->data[3] = ecc & ECC_SEG;
> +
> + /* Error occurred during transmission? */
> + if ((ecc & ECC_DIR) == 0)
> + cf->data[2] |= CAN_ERR_PROT_TX;
> +
> + spin_lock_irqsave(&priv->lock, flags);
> + priv->need_clear_ecc = true;
> + spin_unlock_irqrestore(&priv->lock, flags);
> +
> + schedule_work(&priv->handle_clear_reg_work);
> + }
> +
> + if (isrc & 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: %x\n",
> + can_state);
> + }
> +
> + if (isrc & IRQ_ALI) {
> + /* arbitration lost interrupt */
> + netdev_dbg(netdev, "arbitration lost interrupt\n");
> +
> + priv->can.can_stats.arbitration_lost++;
> + stats->tx_errors++;
> + cf->can_id |= CAN_ERR_LOSTARB;
> + cf->data[0] = alc & 0x1f;
> +
> + spin_lock_irqsave(&priv->lock, flags);
> + priv->need_clear_alc = true;
> + spin_unlock_irqrestore(&priv->lock, flags);
> +
> + schedule_work(&priv->handle_clear_reg_work);
> + }
> +
> + if (can_state != priv->can.state) {
> + tx_state = txerr >= rxerr ? can_state : 0;
> + rx_state = txerr <= rxerr ? can_state : 0;
> +
> + can_change_state(netdev, cf, tx_state, rx_state);
> +
> + if (can_state == CAN_STATE_BUS_OFF)
> + can_bus_off(netdev);
> + }
> +
> + stats->rx_packets++;
> + stats->rx_bytes += cf->can_dlc;
> + netif_rx(skb);
> + }
> +
> + /* handle TX */
> + if ((isrc & IRQ_TI) && can_state != CAN_STATE_BUS_OFF) {
> + /* transmission buffer released */
> + if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
> + !(sr & 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);
> + }
> +
> +resubmit_urb:
> + status = usb_submit_urb(urb, GFP_ATOMIC);
> + if (status) {
> + netdev_err(netdev,
> + "%s: failed resubmitting int bulk urb: %d\n",
> + __func__, status);
> +
> + if (status == -ENODEV)
> + netif_device_detach(netdev);
> + }
> +}
> +
> +static netdev_tx_t f81604_start_xmit(struct sk_buff *skb,
> + struct net_device *netdev)
> +{
> + struct net_device_stats *stats;
> + struct f81604_port_priv *priv;
> + struct can_frame *cf;
> + int status;
> + u8 *ptr;
> + u32 id;
> +
> + priv = netdev_priv(netdev);
> + cf = (struct can_frame *)skb->data;
> + stats = &netdev->stats;
> +
> + if (can_dropped_invalid_skb(netdev, skb))
> + return NETDEV_TX_OK;
> +
> + netif_stop_queue(netdev);
> +
> + ptr = priv->bulk_write_buffer;
> + memset(ptr, 0, F81604_DATA_SIZE);
> +
> + ptr[0] = F81604_CMD_DATA;
> + ptr[1] = min_t(u8, cf->can_dlc & 0xf, 8);
> +
> + if (cf->can_id & CAN_EFF_FLAG) {
> + id = (cf->can_id & CAN_ERR_MASK) << 3;
> + ptr[1] |= F81604_EFF_BIT;
> + ptr[2] = (id >> 24) & 0xff;
> + ptr[3] = (id >> 16) & 0xff;
> + ptr[4] = (id >> 8) & 0xff;
> + ptr[5] = (id >> 0) & 0xff;
> + memcpy(&ptr[6], cf->data, ptr[1]);
> + } else {
> + id = (cf->can_id & CAN_ERR_MASK) << 5;
> + ptr[2] = (id >> 8) & 0xff;
> + ptr[3] = (id >> 0) & 0xff;
> + memcpy(&ptr[4], cf->data, ptr[1]);
> + }
> +
> + if (cf->can_id & CAN_RTR_FLAG)
> + ptr[1] |= F81604_RTR_BIT;
> +
> + can_put_echo_skb(skb, netdev, 0, 0);
> +
> + status = usb_submit_urb(priv->write_urb, GFP_ATOMIC);
> + if (status) {
> + netdev_err(netdev, "%s: failed resubmitting tx bulk urb: %d\n",
> + __func__, status);
> +
> + can_free_echo_skb(netdev, 0, NULL);
> + stats->tx_dropped++;
> +
> + if (status == -ENODEV)
> + netif_device_detach(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);
> + int status;
> + u8 txerr;
> + u8 rxerr;
> +
> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_TXERR, &txerr);
> + if (status)
> + return status;
> +
> + status = f81604_get_sja1000_register(priv->dev, netdev->dev_id,
> + SJA1000_RXERR, &rxerr);
> + if (status)
> + return status;
> +
> + bec->txerr = txerr;
> + bec->rxerr = rxerr;
> +
> + return 0;
> +}
> +
> +static void f81604_remove_urbs(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> + int i;
> +
> + for (i = 0; i < F81604_MAX_RX_URBS; ++i)
> + usb_free_urb(priv->read_urb[i]);
> +
> + usb_free_urb(priv->write_urb);
> + usb_free_urb(priv->int_urb);
> +}
> +
> +static int f81604_prepare_urbs(struct net_device *netdev)
> +{
> + static u8 bulk_in_addr[F81604_MAX_DEV] = { 0x82, 0x84 };
> + static u8 bulk_out_addr[F81604_MAX_DEV] = { 0x01, 0x03 };
> + static u8 int_in_addr[F81604_MAX_DEV] = { 0x81, 0x83 };
> + struct f81604_port_priv *priv;
> + int id;
> + int i;
> +
> + priv = netdev_priv(netdev);
> + id = netdev->dev_id;
> +
> + /* initialize to NULL for error recovery */
> + for (i = 0; i < F81604_MAX_RX_URBS; ++i)
> + priv->read_urb[i] = NULL;
> +
> + priv->write_urb = NULL;
> + priv->int_urb = NULL;
> +
> + for (i = 0; i < F81604_MAX_RX_URBS; ++i) {
> + priv->read_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
> + if (!priv->read_urb[i])
> + goto error;
> +
> + usb_fill_bulk_urb(priv->read_urb[i], priv->dev,
> + usb_rcvbulkpipe(priv->dev, bulk_in_addr[id]),
> + priv->bulk_read_buffer[i], F81604_BULK_SIZE,
> + f81604_read_bulk_callback, netdev);
> + }
> +
> + priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
> + if (!priv->write_urb)
> + goto error;
> +
> + usb_fill_bulk_urb(priv->write_urb, priv->dev,
> + usb_sndbulkpipe(priv->dev, bulk_out_addr[id]),
> + priv->bulk_write_buffer, F81604_DATA_SIZE,
> + f81604_write_bulk_callback, netdev);
> +
> + priv->int_urb = usb_alloc_urb(0, GFP_KERNEL);
> + if (!priv->int_urb)
> + goto error;
> +
> + usb_fill_int_urb(priv->int_urb, priv->dev,
> + usb_rcvintpipe(priv->dev, int_in_addr[id]),
> + priv->int_read_buffer, F81604_INT_SIZE,
> + f81604_read_int_callback, netdev, 1);
> +
> + return 0;
> +
> +error:
> + f81604_remove_urbs(netdev);
> + return -ENOMEM;
> +}
> +
> +/* Open USB device */
> +static int f81604_open(struct net_device *netdev)
> +{
> + int err;
> +
> + err = f81604_prepare_urbs(netdev);
> + if (err)
> + return err;
> +
> + err = open_candev(netdev);
> + if (err)
> + goto remove_urbs;
> +
> + err = f81604_start(netdev);
> + if (err)
> + goto start_failed;
> +
> + netif_start_queue(netdev);
> + return 0;
> +
> +start_failed:
> + if (err == -ENODEV)
> + netif_device_detach(netdev);
> +
> + close_candev(netdev);
> +
> +remove_urbs:
> + f81604_remove_urbs(netdev);
> +
> + return err;
> +}
> +
> +/* Close USB device */
> +static int f81604_close(struct net_device *netdev)
> +{
> + struct f81604_port_priv *priv = netdev_priv(netdev);
> +
> + f81604_set_reset_mode(netdev);
> +
> + netif_stop_queue(netdev);
> + cancel_work_sync(&priv->handle_clear_overrun_work);
> + cancel_work_sync(&priv->handle_clear_reg_work);
> + close_candev(netdev);
> +
> + f81604_unregister_urbs(netdev);
> + f81604_remove_urbs(netdev);
> +
> + 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 = "f81604",
> + .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);
> + int i;
> +
> + for (i = 0; i < F81604_MAX_DEV; ++i) {
> + if (!priv->netdev[i])
> + continue;
> +
> + unregister_netdev(priv->netdev[i]);
> + free_candev(priv->netdev[i]);
> + }
What about closing USB device? It is called brefore disconnect or it
should be done here?

> +}
> +
> +static int f81604_probe(struct usb_interface *intf,
> + const struct usb_device_id *id)
> +{
> + struct f81604_port_priv *port_priv;
> + struct net_device *netdev;
> + struct f81604_priv *priv;
> + struct usb_device *dev;
> + int i, err;
> +
> + dev_info(&intf->dev, "Detected Fintek F81604 device.\n");
> + dev_info(&intf->dev,
> + "Please download newest driver from Fintek website\n");
> + dev_info(&intf->dev, "if you want to use customized functions.\n");
> +
> + dev = interface_to_usbdev(intf);
> +
> + priv = devm_kzalloc(&intf->dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + usb_set_intfdata(intf, priv);
> +
> + for (i = 0; i < F81604_MAX_DEV; ++i) {
> + netdev = alloc_candev(sizeof(*port_priv), 1);
> + if (!netdev) {
> + dev_err(&intf->dev, "Couldn't alloc candev: %d\n", i);
> + err = -ENOMEM;
> +
> + goto failure_cleanup;
> + }
> +
> + port_priv = netdev_priv(netdev);
> + netdev->dev_id = i;
> +
> + spin_lock_init(&port_priv->lock);
> + INIT_WORK(&port_priv->handle_clear_overrun_work,
> + f81604_handle_clear_overrun_work);
> + INIT_WORK(&port_priv->handle_clear_reg_work,
> + f81604_handle_clear_reg_work);
> +
> + port_priv->intf = intf;
> + port_priv->dev = dev;
> + port_priv->ocr = OCR_TX0_PUSHPULL | OCR_TX1_PUSHPULL;
> + port_priv->cdr = CDR_CBP;
> + port_priv->can.state = CAN_STATE_STOPPED;
> + port_priv->can.clock.freq = 24000000 / 2;
> +
> + 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_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;
> +
> + port_priv->can.ctrlmode_supported |= CAN_CTRLMODE_PRESUME_ACK;
> + netdev->netdev_ops = &f81604_netdev_ops;
> + netdev->flags |= IFF_ECHO;
> +
> + SET_NETDEV_DEV(netdev, &intf->dev);
> +
> + err = register_candev(netdev);
> + if (err) {
> + netdev_err(netdev,
> + "couldn't register CAN device: %d\n", err);
> + free_candev(netdev);
> +
> + goto failure_cleanup;
> + }
> +
> + port_priv->netdev = netdev;
> + 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 err;
> +}
> +
> +static struct usb_driver f81604_driver = {
> + .name = "f81604",
> + .probe = f81604_probe,
> + .disconnect = f81604_disconnect,
> + .id_table = f81604_table,
> +};
> +
> +module_usb_driver(f81604_driver);
> +
> +MODULE_AUTHOR("Ji-Ze Hong (Peter Hong) <[email protected]>");
> +MODULE_DESCRIPTION("Fintek F81604 USB to 2xCANBUS");
> +MODULE_LICENSE("GPL");
> --
> 2.17.1
>

2023-03-20 03:01:08

by Peter Hong

[permalink] [raw]
Subject: Re: [PATCH] can: usb: f81604: add Fintek F81604 support

Hi,

Michal Swiatkowski 於 2023/3/17 下午 09:15 寫道:
> On Fri, Mar 17, 2023 at 05:33:52PM +0800, Ji-Ze Hong (Peter Hong) wrote:
>
> --- a/drivers/net/can/usb/Kconfig
> +++ b/drivers/net/can/usb/Kconfig
> @@ -147,4 +147,13 @@ config CAN_UCAN
> from Theobroma Systems like the A31-ÂľQ7 and the RK3399-Q7
> (https://www.theobroma-systems.com/rk3399-q7)
>
> Hi,
>
> I am not familiar with CAN, so only style review :)

Thanks for your reviews :D
> +
> + if (status) {
> + dev_err(&dev->dev, "%s: reg: %x data: %x failed: %d\n",
> + __func__, reg, data, status);
> + }
> The { and } aren't needed as inside if is only one line.

Could I remove the { and } when the logical line to split multi-line ?

>> +static int f81604_set_normal_mode(struct net_device *netdev)
>> +{
>> + struct f81604_port_priv *priv = netdev_priv(netdev);
>> + int status, i;
>> + u8 mod_reg_val = 0x00;
> RCT, mod_reg should be one line above

What mean about "RCT"?

Is this section should change to above like ??

    u8 mod_reg_val;
    ...

    mod_reg_val = 0;
>> +static int f81604_register_urbs(struct net_device *netdev)
>> +{
>> + struct f81604_port_priv *priv = netdev_priv(netdev);
>> + int status, i;
>> +
>> + for (i = 0; i < F81604_MAX_RX_URBS; ++i) {
>> + status = usb_submit_urb(priv->read_urb[i], GFP_KERNEL);
>> + if (status) {
>> + netdev_warn(netdev, "%s: submit rx urb failed: %d\n",
>> + __func__, status);
>> + return status;
> Don't know usb subsytem, but shouldn't previously submitted urb be
> killed?

Yes, I had made kill operations in
    f81604_start()
        -> f81604_unregister_urbs()

>> +static void f81604_process_rx_packet(struct urb *urb)
>> +{
>> + struct net_device_stats *stats;
>> + struct net_device *netdev;
>> + struct can_frame *cf;
>> + struct sk_buff *skb;
>> + u8 *data;
>> + u8 *ptr;
>> + int i;
>> + int count;
> RCT
>
>> +
>> + netdev = urb->context;
>> + stats = &netdev->stats;
>> + data = urb->transfer_buffer;
> netdev and data can be set in declaration

why only netdev & data ?? Could I set netdev, stats & data in declaration ?


>> +/* 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);
>> + int i;
>> +
>> + for (i = 0; i < F81604_MAX_DEV; ++i) {
>> + if (!priv->netdev[i])
>> + continue;
>> +
>> + unregister_netdev(priv->netdev[i]);
>> + free_candev(priv->netdev[i]);
>> + }
> What about closing USB device? It is called brefore disconnect or it
> should be done here?

When candev close in f81604_close(), It will call f81604_set_reset_mode() to
make candev to reset mode.

Thanks

2023-03-20 07:25:13

by Michal Swiatkowski

[permalink] [raw]
Subject: Re: [PATCH] can: usb: f81604: add Fintek F81604 support

On Mon, Mar 20, 2023 at 10:59:33AM +0800, Peter Hong wrote:
> Hi,
>
> Michal Swiatkowski 於 2023/3/17 下午 09:15 寫道:
> > On Fri, Mar 17, 2023 at 05:33:52PM +0800, Ji-Ze Hong (Peter Hong) wrote:
> >
> > --- a/drivers/net/can/usb/Kconfig
> > +++ b/drivers/net/can/usb/Kconfig
> > @@ -147,4 +147,13 @@ config CAN_UCAN
> > from Theobroma Systems like the A31-ÂľQ7 and the RK3399-Q7
> > (https://www.theobroma-systems.com/rk3399-q7)
> > Hi,
> >
> > I am not familiar with CAN, so only style review :)
>
> Thanks for your reviews :D
> > +
> > + if (status) {
> > + dev_err(&dev->dev, "%s: reg: %x data: %x failed: %d\n",
> > + __func__, reg, data, status);
> > + }
> > The { and } aren't needed as inside if is only one line.
>
> Could I remove the { and } when the logical line to split multi-line ?
>

Yes You can, and You should :)

> > > +static int f81604_set_normal_mode(struct net_device *netdev)
> > > +{
> > > + struct f81604_port_priv *priv = netdev_priv(netdev);
> > > + int status, i;
> > > + u8 mod_reg_val = 0x00;
> > RCT, mod_reg should be one line above
>
> What mean about "RCT"?
>
> Is this section should change to above like ??
>
>     u8 mod_reg_val;
>     ...
>
>     mod_reg_val = 0;

reverse christmas tree, it is about how variable definition should look
like. In Your case:

struct f81604_port_priv *priv = netdev_priv(netdev);
u8 mod_reg_val = 0x00;
int status, i;

instead of


struct f81604_port_priv *priv = netdev_priv(netdev);
int status, i;
u8 mod_reg_val = 0x00;

Cosmetic Linux style rule

> > > +static int f81604_register_urbs(struct net_device *netdev)
> > > +{
> > > + struct f81604_port_priv *priv = netdev_priv(netdev);
> > > + int status, i;
> > > +
> > > + for (i = 0; i < F81604_MAX_RX_URBS; ++i) {
> > > + status = usb_submit_urb(priv->read_urb[i], GFP_KERNEL);
> > > + if (status) {
> > > + netdev_warn(netdev, "%s: submit rx urb failed: %d\n",
> > > + __func__, status);
> > > + return status;
> > Don't know usb subsytem, but shouldn't previously submitted urb be
> > killed?
>
> Yes, I had made kill operations in
>     f81604_start()
>         -> f81604_unregister_urbs()
>

Ok, thanks

> > > +static void f81604_process_rx_packet(struct urb *urb)
> > > +{
> > > + struct net_device_stats *stats;
> > > + struct net_device *netdev;
> > > + struct can_frame *cf;
> > > + struct sk_buff *skb;
> > > + u8 *data;
> > > + u8 *ptr;
> > > + int i;
> > > + int count;
> > RCT
> >
> > > +
> > > + netdev = urb->context;
> > > + stats = &netdev->stats;
> > > + data = urb->transfer_buffer;
> > netdev and data can be set in declaration
>
> why only netdev & data ?? Could I set netdev, stats & data in declaration ?
>

You can, but it will be hard to still have declaration as RCT (netdev
declaration have to be before stats declaration).

>
> > > +/* 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);
> > > + int i;
> > > +
> > > + for (i = 0; i < F81604_MAX_DEV; ++i) {
> > > + if (!priv->netdev[i])
> > > + continue;
> > > +
> > > + unregister_netdev(priv->netdev[i]);
> > > + free_candev(priv->netdev[i]);
> > > + }
> > What about closing USB device? It is called brefore disconnect or it
> > should be done here?
>
> When candev close in f81604_close(), It will call f81604_set_reset_mode() to
> make candev to reset mode.
>

Understand, thanks

> Thanks

2023-03-20 10:22:07

by Steen Hegelund

[permalink] [raw]
Subject: Re: [PATCH] can: usb: f81604: add Fintek F81604 support

Hi Peter,

Besides what Michal has mentioned, I noted this:

On Fri Mar 17, 2023 at 10:33 AM CET, Ji-Ze Hong (Peter Hong) wrote:
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> This patch add support for Fintek USB to 2CAN controller support.
>
> Signed-off-by: Ji-Ze Hong (Peter Hong) <[email protected]>
> ---

..snip...

> +static int f81604_prepare_urbs(struct net_device *netdev)
> +{
> + static u8 bulk_in_addr[F81604_MAX_DEV] = { 0x82, 0x84 };
> + static u8 bulk_out_addr[F81604_MAX_DEV] = { 0x01, 0x03 };
> + static u8 int_in_addr[F81604_MAX_DEV] = { 0x81, 0x83 };

These 3 should be made const

> + struct f81604_port_priv *priv;
> + int id;

..snip...

> + int i;
> +MODULE_AUTHOR("Ji-Ze Hong (Peter Hong) <[email protected]>");
> +MODULE_DESCRIPTION("Fintek F81604 USB to 2xCANBUS");
> +MODULE_LICENSE("GPL");
> --
> 2.17.1


BR
Steen