diff options
Diffstat (limited to 'drivers/net/can/usb/usb_8dev.c')
| -rw-r--r-- | drivers/net/can/usb/usb_8dev.c | 1026 |
1 files changed, 1026 insertions, 0 deletions
diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c new file mode 100644 index 000000000..885c54c6f --- /dev/null +++ b/drivers/net/can/usb/usb_8dev.c @@ -0,0 +1,1026 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * CAN driver for "8 devices" USB2CAN converter + * + * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at) + * + * This driver is inspired by the 3.2.0 version of drivers/net/can/usb/ems_usb.c + * and drivers/net/can/usb/esd_usb2.c + * + * Many thanks to Gerhard Bertelsmann (info@gerhard-bertelsmann.de) + * for testing and fixing this driver. Also many thanks to "8 devices", + * who were very cooperative and answered my questions. + */ + +#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> +#include <linux/can/led.h> + +/* driver constants */ +#define MAX_RX_URBS 20 +#define MAX_TX_URBS 20 +#define RX_BUFFER_SIZE 64 + +/* vendor and product id */ +#define USB_8DEV_VENDOR_ID 0x0483 +#define USB_8DEV_PRODUCT_ID 0x1234 + +/* endpoints */ +enum usb_8dev_endpoint { + USB_8DEV_ENDP_DATA_RX = 1, + USB_8DEV_ENDP_DATA_TX, + USB_8DEV_ENDP_CMD_RX, + USB_8DEV_ENDP_CMD_TX +}; + +/* device CAN clock */ +#define USB_8DEV_ABP_CLOCK 32000000 + +/* setup flags */ +#define USB_8DEV_SILENT 0x01 +#define USB_8DEV_LOOPBACK 0x02 +#define USB_8DEV_DISABLE_AUTO_RESTRANS 0x04 +#define USB_8DEV_STATUS_FRAME 0x08 + +/* commands */ +enum usb_8dev_cmd { + USB_8DEV_RESET = 1, + USB_8DEV_OPEN, + USB_8DEV_CLOSE, + USB_8DEV_SET_SPEED, + USB_8DEV_SET_MASK_FILTER, + USB_8DEV_GET_STATUS, + USB_8DEV_GET_STATISTICS, + USB_8DEV_GET_SERIAL, + USB_8DEV_GET_SOFTW_VER, + USB_8DEV_GET_HARDW_VER, + USB_8DEV_RESET_TIMESTAMP, + USB_8DEV_GET_SOFTW_HARDW_VER +}; + +/* command options */ +#define USB_8DEV_BAUD_MANUAL 0x09 +#define USB_8DEV_CMD_START 0x11 +#define USB_8DEV_CMD_END 0x22 + +#define USB_8DEV_CMD_SUCCESS 0 +#define USB_8DEV_CMD_ERROR 255 + +#define USB_8DEV_CMD_TIMEOUT 1000 + +/* frames */ +#define USB_8DEV_DATA_START 0x55 +#define USB_8DEV_DATA_END 0xAA + +#define USB_8DEV_TYPE_CAN_FRAME 0 +#define USB_8DEV_TYPE_ERROR_FRAME 3 + +#define USB_8DEV_EXTID 0x01 +#define USB_8DEV_RTR 0x02 +#define USB_8DEV_ERR_FLAG 0x04 + +/* status */ +#define USB_8DEV_STATUSMSG_OK 0x00 /* Normal condition. */ +#define USB_8DEV_STATUSMSG_OVERRUN 0x01 /* Overrun occurred when sending */ +#define USB_8DEV_STATUSMSG_BUSLIGHT 0x02 /* Error counter has reached 96 */ +#define USB_8DEV_STATUSMSG_BUSHEAVY 0x03 /* Error count. has reached 128 */ +#define USB_8DEV_STATUSMSG_BUSOFF 0x04 /* Device is in BUSOFF */ +#define USB_8DEV_STATUSMSG_STUFF 0x20 /* Stuff Error */ +#define USB_8DEV_STATUSMSG_FORM 0x21 /* Form Error */ +#define USB_8DEV_STATUSMSG_ACK 0x23 /* Ack Error */ +#define USB_8DEV_STATUSMSG_BIT0 0x24 /* Bit1 Error */ +#define USB_8DEV_STATUSMSG_BIT1 0x25 /* Bit0 Error */ +#define USB_8DEV_STATUSMSG_CRC 0x27 /* CRC Error */ + +#define USB_8DEV_RP_MASK 0x7F /* Mask for Receive Error Bit */ + + +/* table of devices that work with this driver */ +static const struct usb_device_id usb_8dev_table[] = { + { USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) }, + { } /* Terminating entry */ +}; + +MODULE_DEVICE_TABLE(usb, usb_8dev_table); + +struct usb_8dev_tx_urb_context { + struct usb_8dev_priv *priv; + + u32 echo_index; + u8 dlc; +}; + +/* Structure to hold all of our device specific stuff */ +struct usb_8dev_priv { + 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 usb_8dev_tx_urb_context tx_contexts[MAX_TX_URBS]; + + struct usb_anchor rx_submitted; + + struct can_berr_counter bec; + + u8 *cmd_msg_buffer; + + struct mutex usb_8dev_cmd_lock; + void *rxbuf[MAX_RX_URBS]; + dma_addr_t rxbuf_dma[MAX_RX_URBS]; +}; + +/* tx frame */ +struct __packed usb_8dev_tx_msg { + u8 begin; + u8 flags; /* RTR and EXT_ID flag */ + __be32 id; /* upper 3 bits not used */ + u8 dlc; /* data length code 0-8 bytes */ + u8 data[8]; /* 64-bit data */ + u8 end; +}; + +/* rx frame */ +struct __packed usb_8dev_rx_msg { + u8 begin; + u8 type; /* frame type */ + u8 flags; /* RTR and EXT_ID flag */ + __be32 id; /* upper 3 bits not used */ + u8 dlc; /* data length code 0-8 bytes */ + u8 data[8]; /* 64-bit data */ + __be32 timestamp; /* 32-bit timestamp */ + u8 end; +}; + +/* command frame */ +struct __packed usb_8dev_cmd_msg { + u8 begin; + u8 channel; /* unknown - always 0 */ + u8 command; /* command to execute */ + u8 opt1; /* optional parameter / return value */ + u8 opt2; /* optional parameter 2 */ + u8 data[10]; /* optional parameter and data */ + u8 end; +}; + +static int usb_8dev_send_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size) +{ + int actual_length; + + return usb_bulk_msg(priv->udev, + usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_TX), + msg, size, &actual_length, USB_8DEV_CMD_TIMEOUT); +} + +static int usb_8dev_wait_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size, + int *actual_length) +{ + return usb_bulk_msg(priv->udev, + usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_RX), + msg, size, actual_length, USB_8DEV_CMD_TIMEOUT); +} + +/* Send command to device and receive result. + * Command was successful when opt1 = 0. + */ +static int usb_8dev_send_cmd(struct usb_8dev_priv *priv, + struct usb_8dev_cmd_msg *out, + struct usb_8dev_cmd_msg *in) +{ + int err; + int num_bytes_read; + struct net_device *netdev; + + netdev = priv->netdev; + + out->begin = USB_8DEV_CMD_START; + out->end = USB_8DEV_CMD_END; + + mutex_lock(&priv->usb_8dev_cmd_lock); + + memcpy(priv->cmd_msg_buffer, out, + sizeof(struct usb_8dev_cmd_msg)); + + err = usb_8dev_send_cmd_msg(priv, priv->cmd_msg_buffer, + sizeof(struct usb_8dev_cmd_msg)); + if (err < 0) { + netdev_err(netdev, "sending command message failed\n"); + goto failed; + } + + err = usb_8dev_wait_cmd_msg(priv, priv->cmd_msg_buffer, + sizeof(struct usb_8dev_cmd_msg), + &num_bytes_read); + if (err < 0) { + netdev_err(netdev, "no command message answer\n"); + goto failed; + } + + memcpy(in, priv->cmd_msg_buffer, sizeof(struct usb_8dev_cmd_msg)); + + if (in->begin != USB_8DEV_CMD_START || in->end != USB_8DEV_CMD_END || + num_bytes_read != 16 || in->opt1 != 0) + err = -EPROTO; + +failed: + mutex_unlock(&priv->usb_8dev_cmd_lock); + return err; +} + +/* Send open command to device */ +static int usb_8dev_cmd_open(struct usb_8dev_priv *priv) +{ + struct can_bittiming *bt = &priv->can.bittiming; + struct usb_8dev_cmd_msg outmsg; + struct usb_8dev_cmd_msg inmsg; + u32 ctrlmode = priv->can.ctrlmode; + u32 flags = USB_8DEV_STATUS_FRAME; + __be32 beflags; + __be16 bebrp; + + memset(&outmsg, 0, sizeof(outmsg)); + outmsg.command = USB_8DEV_OPEN; + outmsg.opt1 = USB_8DEV_BAUD_MANUAL; + outmsg.data[0] = bt->prop_seg + bt->phase_seg1; + outmsg.data[1] = bt->phase_seg2; + outmsg.data[2] = bt->sjw; + + /* BRP */ + bebrp = cpu_to_be16((u16)bt->brp); + memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp)); + + /* flags */ + if (ctrlmode & CAN_CTRLMODE_LOOPBACK) + flags |= USB_8DEV_LOOPBACK; + if (ctrlmode & CAN_CTRLMODE_LISTENONLY) + flags |= USB_8DEV_SILENT; + if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) + flags |= USB_8DEV_DISABLE_AUTO_RESTRANS; + + beflags = cpu_to_be32(flags); + memcpy(&outmsg.data[5], &beflags, sizeof(beflags)); + + return usb_8dev_send_cmd(priv, &outmsg, &inmsg); +} + +/* Send close command to device */ +static int usb_8dev_cmd_close(struct usb_8dev_priv *priv) +{ + struct usb_8dev_cmd_msg inmsg; + struct usb_8dev_cmd_msg outmsg = { + .channel = 0, + .command = USB_8DEV_CLOSE, + .opt1 = 0, + .opt2 = 0 + }; + + return usb_8dev_send_cmd(priv, &outmsg, &inmsg); +} + +/* Get firmware and hardware version */ +static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res) +{ + struct usb_8dev_cmd_msg inmsg; + struct usb_8dev_cmd_msg outmsg = { + .channel = 0, + .command = USB_8DEV_GET_SOFTW_HARDW_VER, + .opt1 = 0, + .opt2 = 0 + }; + + int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg); + if (err) + return err; + + *res = be32_to_cpup((__be32 *)inmsg.data); + + return err; +} + +/* Set network device mode + * + * Maybe we should leave this function empty, because the device + * set mode variable with open command. + */ +static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode) +{ + struct usb_8dev_priv *priv = netdev_priv(netdev); + int err = 0; + + switch (mode) { + case CAN_MODE_START: + err = usb_8dev_cmd_open(priv); + if (err) + netdev_warn(netdev, "couldn't start device"); + break; + + default: + return -EOPNOTSUPP; + } + + return err; +} + +/* Read error/status frames */ +static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv, + struct usb_8dev_rx_msg *msg) +{ + struct can_frame *cf; + struct sk_buff *skb; + struct net_device_stats *stats = &priv->netdev->stats; + + /* Error message: + * byte 0: Status + * byte 1: bit 7: Receive Passive + * byte 1: bit 0-6: Receive Error Counter + * byte 2: Transmit Error Counter + * byte 3: Always 0 (maybe reserved for future use) + */ + + u8 state = msg->data[0]; + u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK; + u8 txerr = msg->data[2]; + int rx_errors = 0; + int tx_errors = 0; + + skb = alloc_can_err_skb(priv->netdev, &cf); + if (!skb) + return; + + switch (state) { + case USB_8DEV_STATUSMSG_OK: + priv->can.state = CAN_STATE_ERROR_ACTIVE; + cf->can_id |= CAN_ERR_PROT; + cf->data[2] = CAN_ERR_PROT_ACTIVE; + break; + case USB_8DEV_STATUSMSG_BUSOFF: + priv->can.state = CAN_STATE_BUS_OFF; + cf->can_id |= CAN_ERR_BUSOFF; + priv->can.can_stats.bus_off++; + can_bus_off(priv->netdev); + break; + case USB_8DEV_STATUSMSG_OVERRUN: + case USB_8DEV_STATUSMSG_BUSLIGHT: + case USB_8DEV_STATUSMSG_BUSHEAVY: + cf->can_id |= CAN_ERR_CRTL; + break; + default: + priv->can.state = CAN_STATE_ERROR_WARNING; + cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; + priv->can.can_stats.bus_error++; + break; + } + + switch (state) { + case USB_8DEV_STATUSMSG_OK: + case USB_8DEV_STATUSMSG_BUSOFF: + break; + case USB_8DEV_STATUSMSG_ACK: + cf->can_id |= CAN_ERR_ACK; + tx_errors = 1; + break; + case USB_8DEV_STATUSMSG_CRC: + cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; + rx_errors = 1; + break; + case USB_8DEV_STATUSMSG_BIT0: + cf->data[2] |= CAN_ERR_PROT_BIT0; + tx_errors = 1; + break; + case USB_8DEV_STATUSMSG_BIT1: + cf->data[2] |= CAN_ERR_PROT_BIT1; + tx_errors = 1; + break; + case USB_8DEV_STATUSMSG_FORM: + cf->data[2] |= CAN_ERR_PROT_FORM; + rx_errors = 1; + break; + case USB_8DEV_STATUSMSG_STUFF: + cf->data[2] |= CAN_ERR_PROT_STUFF; + rx_errors = 1; + break; + case USB_8DEV_STATUSMSG_OVERRUN: + cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; + stats->rx_over_errors++; + rx_errors = 1; + break; + case USB_8DEV_STATUSMSG_BUSLIGHT: + priv->can.state = CAN_STATE_ERROR_WARNING; + cf->data[1] = (txerr > rxerr) ? + CAN_ERR_CRTL_TX_WARNING : + CAN_ERR_CRTL_RX_WARNING; + priv->can.can_stats.error_warning++; + break; + case USB_8DEV_STATUSMSG_BUSHEAVY: + priv->can.state = CAN_STATE_ERROR_PASSIVE; + cf->data[1] = (txerr > rxerr) ? + CAN_ERR_CRTL_TX_PASSIVE : + CAN_ERR_CRTL_RX_PASSIVE; + priv->can.can_stats.error_passive++; + break; + default: + netdev_warn(priv->netdev, + "Unknown status/error message (%d)\n", state); + break; + } + + if (tx_errors) { + cf->data[2] |= CAN_ERR_PROT_TX; + stats->tx_errors++; + } + + if (rx_errors) + stats->rx_errors++; + if (priv->can.state != CAN_STATE_BUS_OFF) { + cf->data[6] = txerr; + cf->data[7] = rxerr; + } + + priv->bec.txerr = txerr; + priv->bec.rxerr = rxerr; + + stats->rx_packets++; + stats->rx_bytes += cf->can_dlc; + netif_rx(skb); +} + +/* Read data and status frames */ +static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv, + struct usb_8dev_rx_msg *msg) +{ + struct can_frame *cf; + struct sk_buff *skb; + struct net_device_stats *stats = &priv->netdev->stats; + + if (msg->type == USB_8DEV_TYPE_ERROR_FRAME && + msg->flags == USB_8DEV_ERR_FLAG) { + usb_8dev_rx_err_msg(priv, msg); + } else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) { + skb = alloc_can_skb(priv->netdev, &cf); + if (!skb) + return; + + cf->can_id = be32_to_cpu(msg->id); + cf->can_dlc = get_can_dlc(msg->dlc & 0xF); + + if (msg->flags & USB_8DEV_EXTID) + cf->can_id |= CAN_EFF_FLAG; + + if (msg->flags & USB_8DEV_RTR) + cf->can_id |= CAN_RTR_FLAG; + else + memcpy(cf->data, msg->data, cf->can_dlc); + + stats->rx_packets++; + stats->rx_bytes += cf->can_dlc; + netif_rx(skb); + + can_led_event(priv->netdev, CAN_LED_EVENT_RX); + } else { + netdev_warn(priv->netdev, "frame type %d unknown", + msg->type); + } + +} + +/* Callback for reading data from device + * + * Check urb status, call read function and resubmit urb read operation. + */ +static void usb_8dev_read_bulk_callback(struct urb *urb) +{ + struct usb_8dev_priv *priv = urb->context; + struct net_device *netdev; + int retval; + int pos = 0; + + netdev = priv->netdev; + + if (!netif_device_present(netdev)) + return; + + switch (urb->status) { + case 0: /* success */ + break; + + case -ENOENT: + case -EPIPE: + case -EPROTO: + case -ESHUTDOWN: + return; + + default: + netdev_info(netdev, "Rx URB aborted (%d)\n", + urb->status); + goto resubmit_urb; + } + + while (pos < urb->actual_length) { + struct usb_8dev_rx_msg *msg; + + if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) { + netdev_err(priv->netdev, "format error\n"); + break; + } + + msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos); + usb_8dev_rx_can_msg(priv, msg); + + pos += sizeof(struct usb_8dev_rx_msg); + } + +resubmit_urb: + usb_fill_bulk_urb(urb, priv->udev, + usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX), + urb->transfer_buffer, RX_BUFFER_SIZE, + usb_8dev_read_bulk_callback, priv); + + 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 handler for write operations + * + * Free allocated buffers, check transmit status and + * calculate statistic. + */ +static void usb_8dev_write_bulk_callback(struct urb *urb) +{ + struct usb_8dev_tx_urb_context *context = urb->context; + struct usb_8dev_priv *priv; + struct net_device *netdev; + + BUG_ON(!context); + + priv = context->priv; + netdev = priv->netdev; + + /* free up our allocated buffer */ + usb_free_coherent(urb->dev, urb->transfer_buffer_length, + urb->transfer_buffer, urb->transfer_dma); + + atomic_dec(&priv->active_tx_urbs); + + if (!netif_device_present(netdev)) + return; + + if (urb->status) + netdev_info(netdev, "Tx URB aborted (%d)\n", + urb->status); + + netdev->stats.tx_packets++; + netdev->stats.tx_bytes += context->dlc; + + can_get_echo_skb(netdev, context->echo_index); + + can_led_event(netdev, CAN_LED_EVENT_TX); + + /* Release context */ + context->echo_index = MAX_TX_URBS; + + netif_wake_queue(netdev); +} + +/* Send data to device */ +static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, + struct net_device *netdev) +{ + struct usb_8dev_priv *priv = netdev_priv(netdev); + struct net_device_stats *stats = &netdev->stats; + struct can_frame *cf = (struct can_frame *) skb->data; + struct usb_8dev_tx_msg *msg; + struct urb *urb; + struct usb_8dev_tx_urb_context *context = NULL; + u8 *buf; + int i, err; + size_t size = sizeof(struct usb_8dev_tx_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(priv->udev, size, GFP_ATOMIC, + &urb->transfer_dma); + if (!buf) { + netdev_err(netdev, "No memory left for USB buffer\n"); + goto nomembuf; + } + + memset(buf, 0, size); + + msg = (struct usb_8dev_tx_msg *)buf; + msg->begin = USB_8DEV_DATA_START; + msg->flags = 0x00; + + if (cf->can_id & CAN_RTR_FLAG) + msg->flags |= USB_8DEV_RTR; + + if (cf->can_id & CAN_EFF_FLAG) + msg->flags |= USB_8DEV_EXTID; + + msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK); + msg->dlc = cf->can_dlc; + memcpy(msg->data, cf->data, cf->can_dlc); + msg->end = USB_8DEV_DATA_END; + + for (i = 0; i < MAX_TX_URBS; i++) { + if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { + context = &priv->tx_contexts[i]; + break; + } + } + + /* May never happen! When this happens we'd more URBs in flight as + * allowed (MAX_TX_URBS). + */ + if (!context) + goto nofreecontext; + + context->priv = priv; + context->echo_index = i; + context->dlc = cf->can_dlc; + + usb_fill_bulk_urb(urb, priv->udev, + usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX), + buf, size, usb_8dev_write_bulk_callback, context); + urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + usb_anchor_urb(urb, &priv->tx_submitted); + + can_put_echo_skb(skb, netdev, context->echo_index); + + atomic_inc(&priv->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(priv->udev, size, buf, urb->transfer_dma); + + atomic_dec(&priv->active_tx_urbs); + + if (err == -ENODEV) + netif_device_detach(netdev); + else + netdev_warn(netdev, "failed tx_urb %d\n", err); + stats->tx_dropped++; + } else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) + /* Slow down tx path */ + 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; + +nofreecontext: + usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); + usb_free_urb(urb); + + netdev_warn(netdev, "couldn't find free context"); + + return NETDEV_TX_BUSY; + +nomembuf: + usb_free_urb(urb); + +nomem: + dev_kfree_skb(skb); + stats->tx_dropped++; + + return NETDEV_TX_OK; +} + +static int usb_8dev_get_berr_counter(const struct net_device *netdev, + struct can_berr_counter *bec) +{ + struct usb_8dev_priv *priv = netdev_priv(netdev); + + bec->txerr = priv->bec.txerr; + bec->rxerr = priv->bec.rxerr; + + return 0; +} + +/* Start USB device */ +static int usb_8dev_start(struct usb_8dev_priv *priv) +{ + struct net_device *netdev = priv->netdev; + int err, i; + + for (i = 0; i < MAX_RX_URBS; i++) { + struct urb *urb = NULL; + u8 *buf; + 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(priv->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, priv->udev, + usb_rcvbulkpipe(priv->udev, + USB_8DEV_ENDP_DATA_RX), + buf, RX_BUFFER_SIZE, + usb_8dev_read_bulk_callback, priv); + urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + usb_anchor_urb(urb, &priv->rx_submitted); + + err = usb_submit_urb(urb, GFP_KERNEL); + if (err) { + usb_unanchor_urb(urb); + usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf, + urb->transfer_dma); + usb_free_urb(urb); + break; + } + + priv->rxbuf[i] = buf; + priv->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"); + + err = usb_8dev_cmd_open(priv); + if (err) + goto failed; + + priv->can.state = CAN_STATE_ERROR_ACTIVE; + + return 0; + +failed: + if (err == -ENODEV) + netif_device_detach(priv->netdev); + + netdev_warn(netdev, "couldn't submit control: %d\n", err); + + return err; +} + +/* Open USB device */ +static int usb_8dev_open(struct net_device *netdev) +{ + struct usb_8dev_priv *priv = netdev_priv(netdev); + int err; + + /* common open */ + err = open_candev(netdev); + if (err) + return err; + + can_led_event(netdev, CAN_LED_EVENT_OPEN); + + /* finally start device */ + err = usb_8dev_start(priv); + if (err) { + if (err == -ENODEV) + netif_device_detach(priv->netdev); + + netdev_warn(netdev, "couldn't start device: %d\n", + err); + + close_candev(netdev); + + return err; + } + + netif_start_queue(netdev); + + return 0; +} + +static void unlink_all_urbs(struct usb_8dev_priv *priv) +{ + int i; + + usb_kill_anchored_urbs(&priv->rx_submitted); + + for (i = 0; i < MAX_RX_URBS; ++i) + usb_free_coherent(priv->udev, RX_BUFFER_SIZE, + priv->rxbuf[i], priv->rxbuf_dma[i]); + + usb_kill_anchored_urbs(&priv->tx_submitted); + atomic_set(&priv->active_tx_urbs, 0); + + for (i = 0; i < MAX_TX_URBS; i++) + priv->tx_contexts[i].echo_index = MAX_TX_URBS; +} + +/* Close USB device */ +static int usb_8dev_close(struct net_device *netdev) +{ + struct usb_8dev_priv *priv = netdev_priv(netdev); + int err = 0; + + /* Send CLOSE command to CAN controller */ + err = usb_8dev_cmd_close(priv); + if (err) + netdev_warn(netdev, "couldn't stop device"); + + priv->can.state = CAN_STATE_STOPPED; + + netif_stop_queue(netdev); + + /* Stop polling */ + unlink_all_urbs(priv); + + close_candev(netdev); + + can_led_event(netdev, CAN_LED_EVENT_STOP); + + return err; +} + +static const struct net_device_ops usb_8dev_netdev_ops = { + .ndo_open = usb_8dev_open, + .ndo_stop = usb_8dev_close, + .ndo_start_xmit = usb_8dev_start_xmit, + .ndo_change_mtu = can_change_mtu, +}; + +static const struct can_bittiming_const usb_8dev_bittiming_const = { + .name = "usb_8dev", + .tseg1_min = 1, + .tseg1_max = 16, + .tseg2_min = 1, + .tseg2_max = 8, + .sjw_max = 4, + .brp_min = 1, + .brp_max = 1024, + .brp_inc = 1, +}; + +/* Probe USB device + * + * Check device and firmware. + * Set supported modes and bittiming constants. + * Allocate some memory. + */ +static int usb_8dev_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct net_device *netdev; + struct usb_8dev_priv *priv; + int i, err = -ENOMEM; + u32 version; + char buf[18]; + struct usb_device *usbdev = interface_to_usbdev(intf); + + /* product id looks strange, better we also check iProduct string */ + if (usb_string(usbdev, usbdev->descriptor.iProduct, buf, + sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) { + dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n"); + return -ENODEV; + } + + netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS); + if (!netdev) { + dev_err(&intf->dev, "Couldn't alloc candev\n"); + return -ENOMEM; + } + + priv = netdev_priv(netdev); + + priv->udev = usbdev; + priv->netdev = netdev; + + priv->can.state = CAN_STATE_STOPPED; + priv->can.clock.freq = USB_8DEV_ABP_CLOCK; + priv->can.bittiming_const = &usb_8dev_bittiming_const; + priv->can.do_set_mode = usb_8dev_set_mode; + priv->can.do_get_berr_counter = usb_8dev_get_berr_counter; + priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | + CAN_CTRLMODE_LISTENONLY | + CAN_CTRLMODE_ONE_SHOT; + + netdev->netdev_ops = &usb_8dev_netdev_ops; + + netdev->flags |= IFF_ECHO; /* we support local echo */ + + init_usb_anchor(&priv->rx_submitted); + + init_usb_anchor(&priv->tx_submitted); + atomic_set(&priv->active_tx_urbs, 0); + + for (i = 0; i < MAX_TX_URBS; i++) + priv->tx_contexts[i].echo_index = MAX_TX_URBS; + + priv->cmd_msg_buffer = devm_kzalloc(&intf->dev, sizeof(struct usb_8dev_cmd_msg), + GFP_KERNEL); + if (!priv->cmd_msg_buffer) + goto cleanup_candev; + + usb_set_intfdata(intf, priv); + + SET_NETDEV_DEV(netdev, &intf->dev); + + mutex_init(&priv->usb_8dev_cmd_lock); + + err = register_candev(netdev); + if (err) { + netdev_err(netdev, + "couldn't register CAN device: %d\n", err); + goto cleanup_candev; + } + + err = usb_8dev_cmd_version(priv, &version); + if (err) { + netdev_err(netdev, "can't get firmware version\n"); + goto cleanup_unregister_candev; + } else { + netdev_info(netdev, + "firmware: %d.%d, hardware: %d.%d\n", + (version>>24) & 0xff, (version>>16) & 0xff, + (version>>8) & 0xff, version & 0xff); + } + + devm_can_led_init(netdev); + + return 0; + +cleanup_unregister_candev: + unregister_netdev(priv->netdev); + +cleanup_candev: + free_candev(netdev); + + return err; + +} + +/* Called by the usb core when driver is unloaded or device is removed */ +static void usb_8dev_disconnect(struct usb_interface *intf) +{ + struct usb_8dev_priv *priv = usb_get_intfdata(intf); + + usb_set_intfdata(intf, NULL); + + if (priv) { + netdev_info(priv->netdev, "device disconnected\n"); + + unregister_netdev(priv->netdev); + unlink_all_urbs(priv); + free_candev(priv->netdev); + } + +} + +static struct usb_driver usb_8dev_driver = { + .name = "usb_8dev", + .probe = usb_8dev_probe, + .disconnect = usb_8dev_disconnect, + .id_table = usb_8dev_table, +}; + +module_usb_driver(usb_8dev_driver); + +MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>"); +MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces"); +MODULE_LICENSE("GPL v2"); |