aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/can/usb/usb_8dev.c
diff options
context:
space:
mode:
authorBernd Krumboeck <b.krumboeck@gmail.com>2013-01-19 07:30:45 +0100
committerMarc Kleine-Budde <mkl@pengutronix.de>2013-01-26 16:58:58 +0100
commit0024d8ad1639e32d717445c69ca813fd19c2a91c (patch)
tree4761a3b7409cdb7be0f03d17b4868ee1d3446db1 /drivers/net/can/usb/usb_8dev.c
parentaf5fd6da40412002bd2ba3293fd11fe862e15d80 (diff)
downloadvexpress-lsk-0024d8ad1639e32d717445c69ca813fd19c2a91c.tar.gz
can: usb_8dev: Add support for USB2CAN interface from 8 devices
Add device driver for USB2CAN interface from "8 devices" (http://www.8devices.com). changes since v10: * small cleanups changes since v9: * fixed syslog messages * fixed crc error number * increased MAX_RX_URBS and MAX_TX_URBS changes since v8: * remove all sysfs files changes since v7: * add sysfs documentation * fix minor styling issue * fixed can state for passive mode * changed handling for crc errors changes since v6: * changed some variable types to big endian equivalent * small cleanups changes since v5: * unlock mutex on error changes since v4: * removed FSF address * renamed struct usb_8dev * removed unused variable free_slots * replaced some _to_cpu functions with pointer equivalent * fix return value for usb_8dev_set_mode * handle can errors with separate function * fix overrun error handling * rewrite error handling for usb_8dev_start_xmit * fix urb submit in usb_8dev_start * various small fixes Acked-by: Wolfgang Grandegger <wg@grandegger.com> Tested-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Bernd Krumboeck <krumboeck@universalnet.at> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'drivers/net/can/usb/usb_8dev.c')
-rw-r--r--drivers/net/can/usb/usb_8dev.c1022
1 files changed, 1022 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 00000000000..a9e73fa4ad0
--- /dev/null
+++ b/drivers/net/can/usb/usb_8dev.c
@@ -0,0 +1,1022 @@
+/*
+ * CAN driver for "8 devices" USB2CAN converter
+ *
+ * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at)
+ *
+ * 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.
+ *
+ * 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/init.h>
+#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>
+
+/* 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 occured 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;
+
+};
+
+/* 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; /* unkown - 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;
+ 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[2] |= CAN_ERR_PROT_UNSPEC;
+ cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ |
+ CAN_ERR_PROT_LOC_CRC_DEL;
+ 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++;
+
+ cf->data[6] = txerr;
+ cf->data[7] = rxerr;
+
+ priv->bec.txerr = txerr;
+ priv->bec.rxerr = rxerr;
+
+ netif_rx(skb);
+
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+}
+
+/* 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);
+
+ netif_rx(skb);
+
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+ } 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 -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);
+
+ /* 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) {
+ netdev_err(netdev, "No memory left for URBs\n");
+ 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))
+ goto failed;
+ 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_unanchor_urb(urb);
+ usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
+
+ netdev_warn(netdev, "couldn't find free context");
+
+ return NETDEV_TX_BUSY;
+
+failed:
+ 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);
+
+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;
+
+ /* create a URB, and a buffer for it */
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ netdev_err(netdev, "No memory left for URBs\n");
+ err = -ENOMEM;
+ break;
+ }
+
+ buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL,
+ &urb->transfer_dma);
+ if (!buf) {
+ netdev_err(netdev, "No memory left for USB buffer\n");
+ usb_free_urb(urb);
+ err = -ENOMEM;
+ break;
+ }
+
+ 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);
+ break;
+ }
+
+ /* 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;
+
+ /* 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);
+
+ 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);
+
+ 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,
+};
+
+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 = kzalloc(sizeof(struct usb_8dev_cmd_msg),
+ GFP_KERNEL);
+ if (!priv->cmd_msg_buffer) {
+ netdev_err(netdev, "Couldn't alloc Tx buffer\n");
+ 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_cmd_msg_buffer;
+ }
+
+ err = usb_8dev_cmd_version(priv, &version);
+ if (err) {
+ netdev_err(netdev, "can't get firmware version\n");
+ goto cleanup_cmd_msg_buffer;
+ } else {
+ netdev_info(netdev,
+ "firmware: %d.%d, hardware: %d.%d\n",
+ (version>>24) & 0xff, (version>>16) & 0xff,
+ (version>>8) & 0xff, version & 0xff);
+ }
+
+ return 0;
+
+cleanup_cmd_msg_buffer:
+ kfree(priv->cmd_msg_buffer);
+
+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);
+ free_candev(priv->netdev);
+
+ unlink_all_urbs(priv);
+ }
+
+}
+
+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");