| /* |
| * CAN driver for EMS Dr. Thomas Wuensche CPC-USB/ARM7 |
| * |
| * Copyright (C) 2004-2009 EMS Dr. Thomas Wuensche |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published |
| * by the Free Software Foundation; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| #include <linux/signal.h> |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/netdevice.h> |
| #include <linux/usb.h> |
| |
| #include <linux/can.h> |
| #include <linux/can/dev.h> |
| #include <linux/can/error.h> |
| |
| MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>"); |
| MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces"); |
| MODULE_LICENSE("GPL v2"); |
| |
| /* Control-Values for CPC_Control() Command Subject Selection */ |
| #define CONTR_CAN_MESSAGE 0x04 |
| #define CONTR_CAN_STATE 0x0C |
| #define CONTR_BUS_ERROR 0x1C |
| |
| /* Control Command Actions */ |
| #define CONTR_CONT_OFF 0 |
| #define CONTR_CONT_ON 1 |
| #define CONTR_ONCE 2 |
| |
| /* Messages from CPC to PC */ |
| #define CPC_MSG_TYPE_CAN_FRAME 1 /* CAN data frame */ |
| #define CPC_MSG_TYPE_RTR_FRAME 8 /* CAN remote frame */ |
| #define CPC_MSG_TYPE_CAN_PARAMS 12 /* Actual CAN parameters */ |
| #define CPC_MSG_TYPE_CAN_STATE 14 /* CAN state message */ |
| #define CPC_MSG_TYPE_EXT_CAN_FRAME 16 /* Extended CAN data frame */ |
| #define CPC_MSG_TYPE_EXT_RTR_FRAME 17 /* Extended remote frame */ |
| #define CPC_MSG_TYPE_CONTROL 19 /* change interface behavior */ |
| #define CPC_MSG_TYPE_CONFIRM 20 /* command processed confirmation */ |
| #define CPC_MSG_TYPE_OVERRUN 21 /* overrun events */ |
| #define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */ |
| #define CPC_MSG_TYPE_ERR_COUNTER 25 /* RX/TX error counter */ |
| |
| /* Messages from the PC to the CPC interface */ |
| #define CPC_CMD_TYPE_CAN_FRAME 1 /* CAN data frame */ |
| #define CPC_CMD_TYPE_CONTROL 3 /* control of interface behavior */ |
| #define CPC_CMD_TYPE_CAN_PARAMS 6 /* set CAN parameters */ |
| #define CPC_CMD_TYPE_RTR_FRAME 13 /* CAN remote frame */ |
| #define CPC_CMD_TYPE_CAN_STATE 14 /* CAN state message */ |
| #define CPC_CMD_TYPE_EXT_CAN_FRAME 15 /* Extended CAN data frame */ |
| #define CPC_CMD_TYPE_EXT_RTR_FRAME 16 /* Extended CAN remote frame */ |
| #define CPC_CMD_TYPE_CAN_EXIT 200 /* exit the CAN */ |
| |
| #define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */ |
| #define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8 /* clear CPC_MSG queue */ |
| #define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */ |
| |
| #define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */ |
| |
| #define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */ |
| |
| /* Overrun types */ |
| #define CPC_OVR_EVENT_CAN 0x01 |
| #define CPC_OVR_EVENT_CANSTATE 0x02 |
| #define CPC_OVR_EVENT_BUSERROR 0x04 |
| |
| /* |
| * If the CAN controller lost a message we indicate it with the highest bit |
| * set in the count field. |
| */ |
| #define CPC_OVR_HW 0x80 |
| |
| /* Size of the "struct ems_cpc_msg" without the union */ |
| #define CPC_MSG_HEADER_LEN 11 |
| #define CPC_CAN_MSG_MIN_SIZE 5 |
| |
| /* Define these values to match your devices */ |
| #define USB_CPCUSB_VENDOR_ID 0x12D6 |
| |
| #define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444 |
| |
| /* Mode register NXP LPC2119/SJA1000 CAN Controller */ |
| #define SJA1000_MOD_NORMAL 0x00 |
| #define SJA1000_MOD_RM 0x01 |
| |
| /* ECC register NXP LPC2119/SJA1000 CAN Controller */ |
| #define SJA1000_ECC_SEG 0x1F |
| #define SJA1000_ECC_DIR 0x20 |
| #define SJA1000_ECC_ERR 0x06 |
| #define SJA1000_ECC_BIT 0x00 |
| #define SJA1000_ECC_FORM 0x40 |
| #define SJA1000_ECC_STUFF 0x80 |
| #define SJA1000_ECC_MASK 0xc0 |
| |
| /* Status register content */ |
| #define SJA1000_SR_BS 0x80 |
| #define SJA1000_SR_ES 0x40 |
| |
| #define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA |
| |
| /* |
| * The device actually uses a 16MHz clock to generate the CAN clock |
| * but it expects SJA1000 bit settings based on 8MHz (is internally |
| * converted). |
| */ |
| #define EMS_USB_ARM7_CLOCK 8000000 |
| |
| #define CPC_TX_QUEUE_TRIGGER_LOW 25 |
| #define CPC_TX_QUEUE_TRIGGER_HIGH 35 |
| |
| /* |
| * CAN-Message representation in a CPC_MSG. Message object type is |
| * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or |
| * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME. |
| */ |
| struct cpc_can_msg { |
| __le32 id; |
| u8 length; |
| u8 msg[8]; |
| }; |
| |
| /* Representation of the CAN parameters for the SJA1000 controller */ |
| struct cpc_sja1000_params { |
| u8 mode; |
| u8 acc_code0; |
| u8 acc_code1; |
| u8 acc_code2; |
| u8 acc_code3; |
| u8 acc_mask0; |
| u8 acc_mask1; |
| u8 acc_mask2; |
| u8 acc_mask3; |
| u8 btr0; |
| u8 btr1; |
| u8 outp_contr; |
| }; |
| |
| /* CAN params message representation */ |
| struct cpc_can_params { |
| u8 cc_type; |
| |
| /* Will support M16C CAN controller in the future */ |
| union { |
| struct cpc_sja1000_params sja1000; |
| } cc_params; |
| }; |
| |
| /* Structure for confirmed message handling */ |
| struct cpc_confirm { |
| u8 error; /* error code */ |
| }; |
| |
| /* Structure for overrun conditions */ |
| struct cpc_overrun { |
| u8 event; |
| u8 count; |
| }; |
| |
| /* SJA1000 CAN errors (compatible to NXP LPC2119) */ |
| struct cpc_sja1000_can_error { |
| u8 ecc; |
| u8 rxerr; |
| u8 txerr; |
| }; |
| |
| /* structure for CAN error conditions */ |
| struct cpc_can_error { |
| u8 ecode; |
| |
| struct { |
| u8 cc_type; |
| |
| /* Other controllers may also provide error code capture regs */ |
| union { |
| struct cpc_sja1000_can_error sja1000; |
| } regs; |
| } cc; |
| }; |
| |
| /* |
| * Structure containing RX/TX error counter. This structure is used to request |
| * the values of the CAN controllers TX and RX error counter. |
| */ |
| struct cpc_can_err_counter { |
| u8 rx; |
| u8 tx; |
| }; |
| |
| /* Main message type used between library and application */ |
| struct __packed ems_cpc_msg { |
| u8 type; /* type of message */ |
| u8 length; /* length of data within union 'msg' */ |
| u8 msgid; /* confirmation handle */ |
| __le32 ts_sec; /* timestamp in seconds */ |
| __le32 ts_nsec; /* timestamp in nano seconds */ |
| |
| union { |
| u8 generic[64]; |
| struct cpc_can_msg can_msg; |
| struct cpc_can_params can_params; |
| struct cpc_confirm confirmation; |
| struct cpc_overrun overrun; |
| struct cpc_can_error error; |
| struct cpc_can_err_counter err_counter; |
| u8 can_state; |
| } msg; |
| }; |
| |
| /* |
| * Table of devices that work with this driver |
| * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet. |
| */ |
| static struct usb_device_id ems_usb_table[] = { |
| {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)}, |
| {} /* Terminating entry */ |
| }; |
| |
| MODULE_DEVICE_TABLE(usb, ems_usb_table); |
| |
| #define RX_BUFFER_SIZE 64 |
| #define CPC_HEADER_SIZE 4 |
| #define INTR_IN_BUFFER_SIZE 4 |
| |
| #define MAX_RX_URBS 10 |
| #define MAX_TX_URBS 10 |
| |
| struct ems_usb; |
| |
| struct ems_tx_urb_context { |
| struct ems_usb *dev; |
| |
| u32 echo_index; |
| u8 dlc; |
| }; |
| |
| struct ems_usb { |
| struct can_priv can; /* must be the first member */ |
| |
| struct sk_buff *echo_skb[MAX_TX_URBS]; |
| |
| struct usb_device *udev; |
| struct net_device *netdev; |
| |
| atomic_t active_tx_urbs; |
| struct usb_anchor tx_submitted; |
| struct ems_tx_urb_context tx_contexts[MAX_TX_URBS]; |
| |
| struct usb_anchor rx_submitted; |
| |
| struct urb *intr_urb; |
| |
| u8 *tx_msg_buffer; |
| |
| u8 *intr_in_buffer; |
| unsigned int free_slots; /* remember number of available slots */ |
| |
| struct ems_cpc_msg active_params; /* active controller parameters */ |
| void *rxbuf[MAX_RX_URBS]; |
| dma_addr_t rxbuf_dma[MAX_RX_URBS]; |
| }; |
| |
| static void ems_usb_read_interrupt_callback(struct urb *urb) |
| { |
| struct ems_usb *dev = urb->context; |
| struct net_device *netdev = dev->netdev; |
| int err; |
| |
| if (!netif_device_present(netdev)) |
| return; |
| |
| switch (urb->status) { |
| case 0: |
| dev->free_slots = dev->intr_in_buffer[1]; |
| if (dev->free_slots > CPC_TX_QUEUE_TRIGGER_HIGH && |
| netif_queue_stopped(netdev)) |
| netif_wake_queue(netdev); |
| break; |
| |
| case -ECONNRESET: /* unlink */ |
| case -ENOENT: |
| case -EPIPE: |
| case -EPROTO: |
| case -ESHUTDOWN: |
| return; |
| |
| default: |
| netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status); |
| break; |
| } |
| |
| err = usb_submit_urb(urb, GFP_ATOMIC); |
| |
| if (err == -ENODEV) |
| netif_device_detach(netdev); |
| else if (err) |
| netdev_err(netdev, "failed resubmitting intr urb: %d\n", err); |
| } |
| |
| static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg) |
| { |
| struct can_frame *cf; |
| struct sk_buff *skb; |
| int i; |
| struct net_device_stats *stats = &dev->netdev->stats; |
| |
| skb = alloc_can_skb(dev->netdev, &cf); |
| if (skb == NULL) |
| return; |
| |
| cf->can_id = le32_to_cpu(msg->msg.can_msg.id); |
| cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF); |
| |
| if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME || |
| msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) |
| cf->can_id |= CAN_EFF_FLAG; |
| |
| if (msg->type == CPC_MSG_TYPE_RTR_FRAME || |
| msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) { |
| cf->can_id |= CAN_RTR_FLAG; |
| } else { |
| for (i = 0; i < cf->can_dlc; i++) |
| cf->data[i] = msg->msg.can_msg.msg[i]; |
| } |
| |
| stats->rx_packets++; |
| stats->rx_bytes += cf->can_dlc; |
| netif_rx(skb); |
| } |
| |
| static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg) |
| { |
| struct can_frame *cf; |
| struct sk_buff *skb; |
| struct net_device_stats *stats = &dev->netdev->stats; |
| |
| skb = alloc_can_err_skb(dev->netdev, &cf); |
| if (skb == NULL) |
| return; |
| |
| if (msg->type == CPC_MSG_TYPE_CAN_STATE) { |
| u8 state = msg->msg.can_state; |
| |
| if (state & SJA1000_SR_BS) { |
| dev->can.state = CAN_STATE_BUS_OFF; |
| cf->can_id |= CAN_ERR_BUSOFF; |
| |
| dev->can.can_stats.bus_off++; |
| can_bus_off(dev->netdev); |
| } else if (state & SJA1000_SR_ES) { |
| dev->can.state = CAN_STATE_ERROR_WARNING; |
| dev->can.can_stats.error_warning++; |
| } else { |
| dev->can.state = CAN_STATE_ERROR_ACTIVE; |
| dev->can.can_stats.error_passive++; |
| } |
| } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) { |
| u8 ecc = msg->msg.error.cc.regs.sja1000.ecc; |
| u8 txerr = msg->msg.error.cc.regs.sja1000.txerr; |
| u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr; |
| |
| /* bus error interrupt */ |
| dev->can.can_stats.bus_error++; |
| stats->rx_errors++; |
| |
| cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; |
| |
| switch (ecc & SJA1000_ECC_MASK) { |
| case SJA1000_ECC_BIT: |
| cf->data[2] |= CAN_ERR_PROT_BIT; |
| break; |
| case SJA1000_ECC_FORM: |
| cf->data[2] |= CAN_ERR_PROT_FORM; |
| break; |
| case SJA1000_ECC_STUFF: |
| cf->data[2] |= CAN_ERR_PROT_STUFF; |
| break; |
| default: |
| cf->data[3] = ecc & SJA1000_ECC_SEG; |
| break; |
| } |
| |
| /* Error occurred during transmission? */ |
| if ((ecc & SJA1000_ECC_DIR) == 0) |
| cf->data[2] |= CAN_ERR_PROT_TX; |
| |
| if (dev->can.state == CAN_STATE_ERROR_WARNING || |
| dev->can.state == CAN_STATE_ERROR_PASSIVE) { |
| cf->can_id |= CAN_ERR_CRTL; |
| cf->data[1] = (txerr > rxerr) ? |
| CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE; |
| } |
| } else if (msg->type == CPC_MSG_TYPE_OVERRUN) { |
| cf->can_id |= CAN_ERR_CRTL; |
| cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; |
| |
| stats->rx_over_errors++; |
| stats->rx_errors++; |
| } |
| |
| stats->rx_packets++; |
| stats->rx_bytes += cf->can_dlc; |
| netif_rx(skb); |
| } |
| |
| /* |
| * callback for bulk IN urb |
| */ |
| static void ems_usb_read_bulk_callback(struct urb *urb) |
| { |
| struct ems_usb *dev = urb->context; |
| struct net_device *netdev; |
| int retval; |
| |
| netdev = dev->netdev; |
| |
| if (!netif_device_present(netdev)) |
| return; |
| |
| switch (urb->status) { |
| case 0: /* success */ |
| break; |
| |
| case -ENOENT: |
| return; |
| |
| default: |
| netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status); |
| goto resubmit_urb; |
| } |
| |
| if (urb->actual_length > CPC_HEADER_SIZE) { |
| struct ems_cpc_msg *msg; |
| u8 *ibuf = urb->transfer_buffer; |
| u8 msg_count, start; |
| |
| msg_count = ibuf[0] & ~0x80; |
| |
| start = CPC_HEADER_SIZE; |
| |
| while (msg_count) { |
| msg = (struct ems_cpc_msg *)&ibuf[start]; |
| |
| switch (msg->type) { |
| case CPC_MSG_TYPE_CAN_STATE: |
| /* Process CAN state changes */ |
| ems_usb_rx_err(dev, msg); |
| break; |
| |
| case CPC_MSG_TYPE_CAN_FRAME: |
| case CPC_MSG_TYPE_EXT_CAN_FRAME: |
| case CPC_MSG_TYPE_RTR_FRAME: |
| case CPC_MSG_TYPE_EXT_RTR_FRAME: |
| ems_usb_rx_can_msg(dev, msg); |
| break; |
| |
| case CPC_MSG_TYPE_CAN_FRAME_ERROR: |
| /* Process errorframe */ |
| ems_usb_rx_err(dev, msg); |
| break; |
| |
| case CPC_MSG_TYPE_OVERRUN: |
| /* Message lost while receiving */ |
| ems_usb_rx_err(dev, msg); |
| break; |
| } |
| |
| start += CPC_MSG_HEADER_LEN + msg->length; |
| msg_count--; |
| |
| if (start > urb->transfer_buffer_length) { |
| netdev_err(netdev, "format error\n"); |
| break; |
| } |
| } |
| } |
| |
| resubmit_urb: |
| usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2), |
| urb->transfer_buffer, RX_BUFFER_SIZE, |
| ems_usb_read_bulk_callback, dev); |
| |
| retval = usb_submit_urb(urb, GFP_ATOMIC); |
| |
| if (retval == -ENODEV) |
| netif_device_detach(netdev); |
| else if (retval) |
| netdev_err(netdev, |
| "failed resubmitting read bulk urb: %d\n", retval); |
| } |
| |
| /* |
| * callback for bulk IN urb |
| */ |
| static void ems_usb_write_bulk_callback(struct urb *urb) |
| { |
| struct ems_tx_urb_context *context = urb->context; |
| struct ems_usb *dev; |
| struct net_device *netdev; |
| |
| BUG_ON(!context); |
| |
| dev = context->dev; |
| netdev = dev->netdev; |
| |
| /* free up our allocated buffer */ |
| usb_free_coherent(urb->dev, urb->transfer_buffer_length, |
| urb->transfer_buffer, urb->transfer_dma); |
| |
| atomic_dec(&dev->active_tx_urbs); |
| |
| if (!netif_device_present(netdev)) |
| return; |
| |
| if (urb->status) |
| netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status); |
| |
| netif_trans_update(netdev); |
| |
| /* transmission complete interrupt */ |
| netdev->stats.tx_packets++; |
| netdev->stats.tx_bytes += context->dlc; |
| |
| can_get_echo_skb(netdev, context->echo_index); |
| |
| /* Release context */ |
| context->echo_index = MAX_TX_URBS; |
| |
| } |
| |
| /* |
| * Send the given CPC command synchronously |
| */ |
| static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg) |
| { |
| int actual_length; |
| |
| /* Copy payload */ |
| memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg, |
| msg->length + CPC_MSG_HEADER_LEN); |
| |
| /* Clear header */ |
| memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE); |
| |
| return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2), |
| &dev->tx_msg_buffer[0], |
| msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE, |
| &actual_length, 1000); |
| } |
| |
| /* |
| * Change CAN controllers' mode register |
| */ |
| static int ems_usb_write_mode(struct ems_usb *dev, u8 mode) |
| { |
| dev->active_params.msg.can_params.cc_params.sja1000.mode = mode; |
| |
| return ems_usb_command_msg(dev, &dev->active_params); |
| } |
| |
| /* |
| * Send a CPC_Control command to change behaviour when interface receives a CAN |
| * message, bus error or CAN state changed notifications. |
| */ |
| static int ems_usb_control_cmd(struct ems_usb *dev, u8 val) |
| { |
| struct ems_cpc_msg cmd; |
| |
| cmd.type = CPC_CMD_TYPE_CONTROL; |
| cmd.length = CPC_MSG_HEADER_LEN + 1; |
| |
| cmd.msgid = 0; |
| |
| cmd.msg.generic[0] = val; |
| |
| return ems_usb_command_msg(dev, &cmd); |
| } |
| |
| /* |
| * Start interface |
| */ |
| static int ems_usb_start(struct ems_usb *dev) |
| { |
| struct net_device *netdev = dev->netdev; |
| int err, i; |
| |
| dev->intr_in_buffer[0] = 0; |
| dev->free_slots = 50; /* initial size */ |
| |
| for (i = 0; i < MAX_RX_URBS; i++) { |
| struct urb *urb = NULL; |
| u8 *buf = NULL; |
| dma_addr_t buf_dma; |
| |
| /* create a URB, and a buffer for it */ |
| urb = usb_alloc_urb(0, GFP_KERNEL); |
| if (!urb) { |
| err = -ENOMEM; |
| break; |
| } |
| |
| buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL, |
| &buf_dma); |
| if (!buf) { |
| netdev_err(netdev, "No memory left for USB buffer\n"); |
| usb_free_urb(urb); |
| err = -ENOMEM; |
| break; |
| } |
| |
| urb->transfer_dma = buf_dma; |
| |
| usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2), |
| buf, RX_BUFFER_SIZE, |
| ems_usb_read_bulk_callback, dev); |
| urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; |
| usb_anchor_urb(urb, &dev->rx_submitted); |
| |
| err = usb_submit_urb(urb, GFP_KERNEL); |
| if (err) { |
| usb_unanchor_urb(urb); |
| usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf, |
| urb->transfer_dma); |
| usb_free_urb(urb); |
| break; |
| } |
| |
| dev->rxbuf[i] = buf; |
| dev->rxbuf_dma[i] = buf_dma; |
| |
| /* Drop reference, USB core will take care of freeing it */ |
| usb_free_urb(urb); |
| } |
| |
| /* Did we submit any URBs */ |
| if (i == 0) { |
| netdev_warn(netdev, "couldn't setup read URBs\n"); |
| return err; |
| } |
| |
| /* Warn if we've couldn't transmit all the URBs */ |
| if (i < MAX_RX_URBS) |
| netdev_warn(netdev, "rx performance may be slow\n"); |
| |
| /* Setup and start interrupt URB */ |
| usb_fill_int_urb(dev->intr_urb, dev->udev, |
| usb_rcvintpipe(dev->udev, 1), |
| dev->intr_in_buffer, |
| INTR_IN_BUFFER_SIZE, |
| ems_usb_read_interrupt_callback, dev, 1); |
| |
| err = usb_submit_urb(dev->intr_urb, GFP_KERNEL); |
| if (err) { |
| netdev_warn(netdev, "intr URB submit failed: %d\n", err); |
| |
| return err; |
| } |
| |
| /* CPC-USB will transfer received message to host */ |
| err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON); |
| if (err) |
| goto failed; |
| |
| /* CPC-USB will transfer CAN state changes to host */ |
| err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON); |
| if (err) |
| goto failed; |
| |
| /* CPC-USB will transfer bus errors to host */ |
| err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON); |
| if (err) |
| goto failed; |
| |
| err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL); |
| if (err) |
| goto failed; |
| |
| dev->can.state = CAN_STATE_ERROR_ACTIVE; |
| |
| return 0; |
| |
| failed: |
| netdev_warn(netdev, "couldn't submit control: %d\n", err); |
| |
| return err; |
| } |
| |
| static void unlink_all_urbs(struct ems_usb *dev) |
| { |
| int i; |
| |
| usb_unlink_urb(dev->intr_urb); |
| |
| usb_kill_anchored_urbs(&dev->rx_submitted); |
| |
| for (i = 0; i < MAX_RX_URBS; ++i) |
| usb_free_coherent(dev->udev, RX_BUFFER_SIZE, |
| dev->rxbuf[i], dev->rxbuf_dma[i]); |
| |
| usb_kill_anchored_urbs(&dev->tx_submitted); |
| atomic_set(&dev->active_tx_urbs, 0); |
| |
| for (i = 0; i < MAX_TX_URBS; i++) |
| dev->tx_contexts[i].echo_index = MAX_TX_URBS; |
| } |
| |
| static int ems_usb_open(struct net_device *netdev) |
| { |
| struct ems_usb *dev = netdev_priv(netdev); |
| int err; |
| |
| err = ems_usb_write_mode(dev, SJA1000_MOD_RM); |
| if (err) |
| return err; |
| |
| /* common open */ |
| err = open_candev(netdev); |
| if (err) |
| return err; |
| |
| /* finally start device */ |
| err = ems_usb_start(dev); |
| if (err) { |
| if (err == -ENODEV) |
| netif_device_detach(dev->netdev); |
| |
| netdev_warn(netdev, "couldn't start device: %d\n", err); |
| |
| close_candev(netdev); |
| |
| return err; |
| } |
| |
| |
| netif_start_queue(netdev); |
| |
| return 0; |
| } |
| |
| static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev) |
| { |
| struct ems_usb *dev = netdev_priv(netdev); |
| struct ems_tx_urb_context *context = NULL; |
| struct net_device_stats *stats = &netdev->stats; |
| struct can_frame *cf = (struct can_frame *)skb->data; |
| struct ems_cpc_msg *msg; |
| struct urb *urb; |
| u8 *buf; |
| int i, err; |
| size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN |
| + sizeof(struct cpc_can_msg); |
| |
| if (can_dropped_invalid_skb(netdev, skb)) |
| return NETDEV_TX_OK; |
| |
| /* create a URB, and a buffer for it, and copy the data to the URB */ |
| urb = usb_alloc_urb(0, GFP_ATOMIC); |
| if (!urb) |
| goto nomem; |
| |
| buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma); |
| if (!buf) { |
| netdev_err(netdev, "No memory left for USB buffer\n"); |
| usb_free_urb(urb); |
| goto nomem; |
| } |
| |
| msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE]; |
| |
| msg->msg.can_msg.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK); |
| msg->msg.can_msg.length = cf->can_dlc; |
| |
| if (cf->can_id & CAN_RTR_FLAG) { |
| msg->type = cf->can_id & CAN_EFF_FLAG ? |
| CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME; |
| |
| msg->length = CPC_CAN_MSG_MIN_SIZE; |
| } else { |
| msg->type = cf->can_id & CAN_EFF_FLAG ? |
| CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME; |
| |
| for (i = 0; i < cf->can_dlc; i++) |
| msg->msg.can_msg.msg[i] = cf->data[i]; |
| |
| msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc; |
| } |
| |
| for (i = 0; i < MAX_TX_URBS; i++) { |
| if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) { |
| context = &dev->tx_contexts[i]; |
| break; |
| } |
| } |
| |
| /* |
| * May never happen! When this happens we'd more URBs in flight as |
| * allowed (MAX_TX_URBS). |
| */ |
| if (!context) { |
| usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); |
| usb_free_urb(urb); |
| |
| netdev_warn(netdev, "couldn't find free context\n"); |
| |
| return NETDEV_TX_BUSY; |
| } |
| |
| context->dev = dev; |
| context->echo_index = i; |
| context->dlc = cf->can_dlc; |
| |
| usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf, |
| size, ems_usb_write_bulk_callback, context); |
| urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; |
| usb_anchor_urb(urb, &dev->tx_submitted); |
| |
| can_put_echo_skb(skb, netdev, context->echo_index); |
| |
| atomic_inc(&dev->active_tx_urbs); |
| |
| err = usb_submit_urb(urb, GFP_ATOMIC); |
| if (unlikely(err)) { |
| can_free_echo_skb(netdev, context->echo_index); |
| |
| usb_unanchor_urb(urb); |
| usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); |
| dev_kfree_skb(skb); |
| |
| atomic_dec(&dev->active_tx_urbs); |
| |
| if (err == -ENODEV) { |
| netif_device_detach(netdev); |
| } else { |
| netdev_warn(netdev, "failed tx_urb %d\n", err); |
| |
| stats->tx_dropped++; |
| } |
| } else { |
| netif_trans_update(netdev); |
| |
| /* Slow down tx path */ |
| if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS || |
| dev->free_slots < CPC_TX_QUEUE_TRIGGER_LOW) { |
| netif_stop_queue(netdev); |
| } |
| } |
| |
| /* |
| * Release our reference to this URB, the USB core will eventually free |
| * it entirely. |
| */ |
| usb_free_urb(urb); |
| |
| return NETDEV_TX_OK; |
| |
| nomem: |
| dev_kfree_skb(skb); |
| stats->tx_dropped++; |
| |
| return NETDEV_TX_OK; |
| } |
| |
| static int ems_usb_close(struct net_device *netdev) |
| { |
| struct ems_usb *dev = netdev_priv(netdev); |
| |
| /* Stop polling */ |
| unlink_all_urbs(dev); |
| |
| netif_stop_queue(netdev); |
| |
| /* Set CAN controller to reset mode */ |
| if (ems_usb_write_mode(dev, SJA1000_MOD_RM)) |
| netdev_warn(netdev, "couldn't stop device"); |
| |
| close_candev(netdev); |
| |
| return 0; |
| } |
| |
| static const struct net_device_ops ems_usb_netdev_ops = { |
| .ndo_open = ems_usb_open, |
| .ndo_stop = ems_usb_close, |
| .ndo_start_xmit = ems_usb_start_xmit, |
| .ndo_change_mtu = can_change_mtu, |
| }; |
| |
| static const struct can_bittiming_const ems_usb_bittiming_const = { |
| .name = "ems_usb", |
| .tseg1_min = 1, |
| .tseg1_max = 16, |
| .tseg2_min = 1, |
| .tseg2_max = 8, |
| .sjw_max = 4, |
| .brp_min = 1, |
| .brp_max = 64, |
| .brp_inc = 1, |
| }; |
| |
| static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode) |
| { |
| struct ems_usb *dev = netdev_priv(netdev); |
| |
| switch (mode) { |
| case CAN_MODE_START: |
| if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL)) |
| netdev_warn(netdev, "couldn't start device"); |
| |
| if (netif_queue_stopped(netdev)) |
| netif_wake_queue(netdev); |
| break; |
| |
| default: |
| return -EOPNOTSUPP; |
| } |
| |
| return 0; |
| } |
| |
| static int ems_usb_set_bittiming(struct net_device *netdev) |
| { |
| struct ems_usb *dev = netdev_priv(netdev); |
| struct can_bittiming *bt = &dev->can.bittiming; |
| u8 btr0, btr1; |
| |
| 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 (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) |
| btr1 |= 0x80; |
| |
| netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); |
| |
| dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0; |
| dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1; |
| |
| return ems_usb_command_msg(dev, &dev->active_params); |
| } |
| |
| static void init_params_sja1000(struct ems_cpc_msg *msg) |
| { |
| struct cpc_sja1000_params *sja1000 = |
| &msg->msg.can_params.cc_params.sja1000; |
| |
| msg->type = CPC_CMD_TYPE_CAN_PARAMS; |
| msg->length = sizeof(struct cpc_can_params); |
| msg->msgid = 0; |
| |
| msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000; |
| |
| /* Acceptance filter open */ |
| sja1000->acc_code0 = 0x00; |
| sja1000->acc_code1 = 0x00; |
| sja1000->acc_code2 = 0x00; |
| sja1000->acc_code3 = 0x00; |
| |
| /* Acceptance filter open */ |
| sja1000->acc_mask0 = 0xFF; |
| sja1000->acc_mask1 = 0xFF; |
| sja1000->acc_mask2 = 0xFF; |
| sja1000->acc_mask3 = 0xFF; |
| |
| sja1000->btr0 = 0; |
| sja1000->btr1 = 0; |
| |
| sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL; |
| sja1000->mode = SJA1000_MOD_RM; |
| } |
| |
| /* |
| * probe function for new CPC-USB devices |
| */ |
| static int ems_usb_probe(struct usb_interface *intf, |
| const struct usb_device_id *id) |
| { |
| struct net_device *netdev; |
| struct ems_usb *dev; |
| int i, err = -ENOMEM; |
| |
| netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS); |
| if (!netdev) { |
| dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n"); |
| return -ENOMEM; |
| } |
| |
| dev = netdev_priv(netdev); |
| |
| dev->udev = interface_to_usbdev(intf); |
| dev->netdev = netdev; |
| |
| dev->can.state = CAN_STATE_STOPPED; |
| dev->can.clock.freq = EMS_USB_ARM7_CLOCK; |
| dev->can.bittiming_const = &ems_usb_bittiming_const; |
| dev->can.do_set_bittiming = ems_usb_set_bittiming; |
| dev->can.do_set_mode = ems_usb_set_mode; |
| dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; |
| |
| netdev->netdev_ops = &ems_usb_netdev_ops; |
| |
| netdev->flags |= IFF_ECHO; /* we support local echo */ |
| |
| init_usb_anchor(&dev->rx_submitted); |
| |
| init_usb_anchor(&dev->tx_submitted); |
| atomic_set(&dev->active_tx_urbs, 0); |
| |
| for (i = 0; i < MAX_TX_URBS; i++) |
| dev->tx_contexts[i].echo_index = MAX_TX_URBS; |
| |
| dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL); |
| if (!dev->intr_urb) |
| goto cleanup_candev; |
| |
| dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL); |
| if (!dev->intr_in_buffer) |
| goto cleanup_intr_urb; |
| |
| dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE + |
| sizeof(struct ems_cpc_msg), GFP_KERNEL); |
| if (!dev->tx_msg_buffer) |
| goto cleanup_intr_in_buffer; |
| |
| usb_set_intfdata(intf, dev); |
| |
| SET_NETDEV_DEV(netdev, &intf->dev); |
| |
| init_params_sja1000(&dev->active_params); |
| |
| err = ems_usb_command_msg(dev, &dev->active_params); |
| if (err) { |
| netdev_err(netdev, "couldn't initialize controller: %d\n", err); |
| goto cleanup_tx_msg_buffer; |
| } |
| |
| err = register_candev(netdev); |
| if (err) { |
| netdev_err(netdev, "couldn't register CAN device: %d\n", err); |
| goto cleanup_tx_msg_buffer; |
| } |
| |
| return 0; |
| |
| cleanup_tx_msg_buffer: |
| kfree(dev->tx_msg_buffer); |
| |
| cleanup_intr_in_buffer: |
| kfree(dev->intr_in_buffer); |
| |
| cleanup_intr_urb: |
| usb_free_urb(dev->intr_urb); |
| |
| cleanup_candev: |
| free_candev(netdev); |
| |
| return err; |
| } |
| |
| /* |
| * called by the usb core when the device is removed from the system |
| */ |
| static void ems_usb_disconnect(struct usb_interface *intf) |
| { |
| struct ems_usb *dev = usb_get_intfdata(intf); |
| |
| usb_set_intfdata(intf, NULL); |
| |
| if (dev) { |
| unregister_netdev(dev->netdev); |
| |
| unlink_all_urbs(dev); |
| |
| usb_free_urb(dev->intr_urb); |
| |
| kfree(dev->intr_in_buffer); |
| kfree(dev->tx_msg_buffer); |
| |
| free_candev(dev->netdev); |
| } |
| } |
| |
| /* usb specific object needed to register this driver with the usb subsystem */ |
| static struct usb_driver ems_usb_driver = { |
| .name = "ems_usb", |
| .probe = ems_usb_probe, |
| .disconnect = ems_usb_disconnect, |
| .id_table = ems_usb_table, |
| }; |
| |
| module_usb_driver(ems_usb_driver); |