diff options
Diffstat (limited to 'drivers/net/can/usb/esd_usb2.c')
| -rw-r--r-- | drivers/net/can/usb/esd_usb2.c | 1132 |
1 files changed, 1132 insertions, 0 deletions
diff --git a/drivers/net/can/usb/esd_usb2.c b/drivers/net/can/usb/esd_usb2.c new file mode 100644 index 00000000000..05a52754f48 --- /dev/null +++ b/drivers/net/can/usb/esd_usb2.c @@ -0,0 +1,1132 @@ +/* + * CAN driver for esd CAN-USB/2 + * + * Copyright (C) 2010 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh + * + * 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/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> + +MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>"); +MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 interfaces"); +MODULE_LICENSE("GPL v2"); + +/* Define these values to match your devices */ +#define USB_ESDGMBH_VENDOR_ID 0x0ab4 +#define USB_CANUSB2_PRODUCT_ID 0x0010 + +#define ESD_USB2_CAN_CLOCK 60000000 +#define ESD_USB2_MAX_NETS 2 + +/* USB2 commands */ +#define CMD_VERSION 1 /* also used for VERSION_REPLY */ +#define CMD_CAN_RX 2 /* device to host only */ +#define CMD_CAN_TX 3 /* also used for TX_DONE */ +#define CMD_SETBAUD 4 /* also used for SETBAUD_REPLY */ +#define CMD_TS 5 /* also used for TS_REPLY */ +#define CMD_IDADD 6 /* also used for IDADD_REPLY */ + +/* esd CAN message flags - dlc field */ +#define ESD_RTR 0x10 + +/* esd CAN message flags - id field */ +#define ESD_EXTID 0x20000000 +#define ESD_EVENT 0x40000000 +#define ESD_IDMASK 0x1fffffff + +/* esd CAN event ids used by this driver */ +#define ESD_EV_CAN_ERROR_EXT 2 + +/* baudrate message flags */ +#define ESD_USB2_UBR 0x80000000 +#define ESD_USB2_LOM 0x40000000 +#define ESD_USB2_NO_BAUDRATE 0x7fffffff +#define ESD_USB2_TSEG1_MIN 1 +#define ESD_USB2_TSEG1_MAX 16 +#define ESD_USB2_TSEG1_SHIFT 16 +#define ESD_USB2_TSEG2_MIN 1 +#define ESD_USB2_TSEG2_MAX 8 +#define ESD_USB2_TSEG2_SHIFT 20 +#define ESD_USB2_SJW_MAX 4 +#define ESD_USB2_SJW_SHIFT 14 +#define ESD_USB2_BRP_MIN 1 +#define ESD_USB2_BRP_MAX 1024 +#define ESD_USB2_BRP_INC 1 +#define ESD_USB2_3_SAMPLES 0x00800000 + +/* esd IDADD message */ +#define ESD_ID_ENABLE 0x80 +#define ESD_MAX_ID_SEGMENT 64 + +/* SJA1000 ECC register (emulated by usb2 firmware) */ +#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 + +/* esd bus state event codes */ +#define ESD_BUSSTATE_MASK 0xc0 +#define ESD_BUSSTATE_WARN 0x40 +#define ESD_BUSSTATE_ERRPASSIVE 0x80 +#define ESD_BUSSTATE_BUSOFF 0xc0 + +#define RX_BUFFER_SIZE 1024 +#define MAX_RX_URBS 4 +#define MAX_TX_URBS 16 /* must be power of 2 */ + +struct header_msg { + u8 len; /* len is always the total message length in 32bit words */ + u8 cmd; + u8 rsvd[2]; +}; + +struct version_msg { + u8 len; + u8 cmd; + u8 rsvd; + u8 flags; + __le32 drv_version; +}; + +struct version_reply_msg { + u8 len; + u8 cmd; + u8 nets; + u8 features; + __le32 version; + u8 name[16]; + __le32 rsvd; + __le32 ts; +}; + +struct rx_msg { + u8 len; + u8 cmd; + u8 net; + u8 dlc; + __le32 ts; + __le32 id; /* upper 3 bits contain flags */ + u8 data[8]; +}; + +struct tx_msg { + u8 len; + u8 cmd; + u8 net; + u8 dlc; + __le32 hnd; + __le32 id; /* upper 3 bits contain flags */ + u8 data[8]; +}; + +struct tx_done_msg { + u8 len; + u8 cmd; + u8 net; + u8 status; + __le32 hnd; + __le32 ts; +}; + +struct id_filter_msg { + u8 len; + u8 cmd; + u8 net; + u8 option; + __le32 mask[ESD_MAX_ID_SEGMENT + 1]; +}; + +struct set_baudrate_msg { + u8 len; + u8 cmd; + u8 net; + u8 rsvd; + __le32 baud; +}; + +/* Main message type used between library and application */ +struct __attribute__ ((packed)) esd_usb2_msg { + union { + struct header_msg hdr; + struct version_msg version; + struct version_reply_msg version_reply; + struct rx_msg rx; + struct tx_msg tx; + struct tx_done_msg txdone; + struct set_baudrate_msg setbaud; + struct id_filter_msg filter; + } msg; +}; + +static struct usb_device_id esd_usb2_table[] = { + {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)}, + {} +}; +MODULE_DEVICE_TABLE(usb, esd_usb2_table); + +struct esd_usb2_net_priv; + +struct esd_tx_urb_context { + struct esd_usb2_net_priv *priv; + u32 echo_index; + int dlc; +}; + +struct esd_usb2 { + struct usb_device *udev; + struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS]; + + struct usb_anchor rx_submitted; + + int net_count; + u32 version; + int rxinitdone; +}; + +struct esd_usb2_net_priv { + struct can_priv can; /* must be the first member */ + + atomic_t active_tx_jobs; + struct usb_anchor tx_submitted; + struct esd_tx_urb_context tx_contexts[MAX_TX_URBS]; + + int open_time; + struct esd_usb2 *usb2; + struct net_device *netdev; + int index; + u8 old_state; + struct can_berr_counter bec; +}; + +static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv, + struct esd_usb2_msg *msg) +{ + struct net_device_stats *stats = &priv->netdev->stats; + struct can_frame *cf; + struct sk_buff *skb; + u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK; + + if (id == ESD_EV_CAN_ERROR_EXT) { + u8 state = msg->msg.rx.data[0]; + u8 ecc = msg->msg.rx.data[1]; + u8 txerr = msg->msg.rx.data[2]; + u8 rxerr = msg->msg.rx.data[3]; + + skb = alloc_can_err_skb(priv->netdev, &cf); + if (skb == NULL) { + stats->rx_dropped++; + return; + } + + if (state != priv->old_state) { + priv->old_state = state; + + switch (state & ESD_BUSSTATE_MASK) { + case ESD_BUSSTATE_BUSOFF: + priv->can.state = CAN_STATE_BUS_OFF; + cf->can_id |= CAN_ERR_BUSOFF; + can_bus_off(priv->netdev); + break; + case ESD_BUSSTATE_WARN: + priv->can.state = CAN_STATE_ERROR_WARNING; + priv->can.can_stats.error_warning++; + break; + case ESD_BUSSTATE_ERRPASSIVE: + priv->can.state = CAN_STATE_ERROR_PASSIVE; + priv->can.can_stats.error_passive++; + break; + default: + priv->can.state = CAN_STATE_ERROR_ACTIVE; + break; + } + } else { + priv->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[2] |= CAN_ERR_PROT_UNSPEC; + cf->data[3] = ecc & SJA1000_ECC_SEG; + break; + } + + /* Error occured during transmission? */ + if (!(ecc & SJA1000_ECC_DIR)) + cf->data[2] |= CAN_ERR_PROT_TX; + + if (priv->can.state == CAN_STATE_ERROR_WARNING || + priv->can.state == CAN_STATE_ERROR_PASSIVE) { + cf->data[1] = (txerr > rxerr) ? + CAN_ERR_CRTL_TX_PASSIVE : + CAN_ERR_CRTL_RX_PASSIVE; + } + cf->data[6] = txerr; + cf->data[7] = rxerr; + } + + netif_rx(skb); + + priv->bec.txerr = txerr; + priv->bec.rxerr = rxerr; + + stats->rx_packets++; + stats->rx_bytes += cf->can_dlc; + } +} + +static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv, + struct esd_usb2_msg *msg) +{ + struct net_device_stats *stats = &priv->netdev->stats; + struct can_frame *cf; + struct sk_buff *skb; + int i; + u32 id; + + if (!netif_device_present(priv->netdev)) + return; + + id = le32_to_cpu(msg->msg.rx.id); + + if (id & ESD_EVENT) { + esd_usb2_rx_event(priv, msg); + } else { + skb = alloc_can_skb(priv->netdev, &cf); + if (skb == NULL) { + stats->rx_dropped++; + return; + } + + cf->can_id = id & ESD_IDMASK; + cf->can_dlc = get_can_dlc(msg->msg.rx.dlc); + + if (id & ESD_EXTID) + cf->can_id |= CAN_EFF_FLAG; + + if (msg->msg.rx.dlc & ESD_RTR) { + cf->can_id |= CAN_RTR_FLAG; + } else { + for (i = 0; i < cf->can_dlc; i++) + cf->data[i] = msg->msg.rx.data[i]; + } + + netif_rx(skb); + + stats->rx_packets++; + stats->rx_bytes += cf->can_dlc; + } + + return; +} + +static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv, + struct esd_usb2_msg *msg) +{ + struct net_device_stats *stats = &priv->netdev->stats; + struct net_device *netdev = priv->netdev; + struct esd_tx_urb_context *context; + + if (!netif_device_present(netdev)) + return; + + context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)]; + + if (!msg->msg.txdone.status) { + stats->tx_packets++; + stats->tx_bytes += context->dlc; + can_get_echo_skb(netdev, context->echo_index); + } else { + stats->tx_errors++; + can_free_echo_skb(netdev, context->echo_index); + } + + /* Release context */ + context->echo_index = MAX_TX_URBS; + atomic_dec(&priv->active_tx_jobs); + + netif_wake_queue(netdev); +} + +static void esd_usb2_read_bulk_callback(struct urb *urb) +{ + struct esd_usb2 *dev = urb->context; + int retval; + int pos = 0; + int i; + + switch (urb->status) { + case 0: /* success */ + break; + + case -ENOENT: + case -ESHUTDOWN: + return; + + default: + dev_info(dev->udev->dev.parent, + "Rx URB aborted (%d)\n", urb->status); + goto resubmit_urb; + } + + while (pos < urb->actual_length) { + struct esd_usb2_msg *msg; + + msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos); + + switch (msg->msg.hdr.cmd) { + case CMD_CAN_RX: + esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg); + break; + + case CMD_CAN_TX: + esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net], + msg); + break; + } + + pos += msg->msg.hdr.len << 2; + + if (pos > urb->actual_length) { + dev_err(dev->udev->dev.parent, "format error\n"); + break; + } + } + +resubmit_urb: + usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1), + urb->transfer_buffer, RX_BUFFER_SIZE, + esd_usb2_read_bulk_callback, dev); + + retval = usb_submit_urb(urb, GFP_ATOMIC); + if (retval == -ENODEV) { + for (i = 0; i < dev->net_count; i++) { + if (dev->nets[i]) + netif_device_detach(dev->nets[i]->netdev); + } + } else if (retval) { + dev_err(dev->udev->dev.parent, + "failed resubmitting read bulk urb: %d\n", retval); + } + + return; +} + +/* + * callback for bulk IN urb + */ +static void esd_usb2_write_bulk_callback(struct urb *urb) +{ + struct esd_tx_urb_context *context = urb->context; + struct esd_usb2_net_priv *priv; + struct esd_usb2 *dev; + struct net_device *netdev; + size_t size = sizeof(struct esd_usb2_msg); + + WARN_ON(!context); + + priv = context->priv; + netdev = priv->netdev; + dev = priv->usb2; + + /* free up our allocated buffer */ + usb_free_coherent(urb->dev, size, + urb->transfer_buffer, urb->transfer_dma); + + if (!netif_device_present(netdev)) + return; + + if (urb->status) + dev_info(netdev->dev.parent, "Tx URB aborted (%d)\n", + urb->status); + + netdev->trans_start = jiffies; +} + +static ssize_t show_firmware(struct device *d, + struct device_attribute *attr, char *buf) +{ + struct usb_interface *intf = to_usb_interface(d); + struct esd_usb2 *dev = usb_get_intfdata(intf); + + return sprintf(buf, "%d.%d.%d\n", + (dev->version >> 12) & 0xf, + (dev->version >> 8) & 0xf, + dev->version & 0xff); +} +static DEVICE_ATTR(firmware, S_IRUGO, show_firmware, NULL); + +static ssize_t show_hardware(struct device *d, + struct device_attribute *attr, char *buf) +{ + struct usb_interface *intf = to_usb_interface(d); + struct esd_usb2 *dev = usb_get_intfdata(intf); + + return sprintf(buf, "%d.%d.%d\n", + (dev->version >> 28) & 0xf, + (dev->version >> 24) & 0xf, + (dev->version >> 16) & 0xff); +} +static DEVICE_ATTR(hardware, S_IRUGO, show_hardware, NULL); + +static ssize_t show_nets(struct device *d, + struct device_attribute *attr, char *buf) +{ + struct usb_interface *intf = to_usb_interface(d); + struct esd_usb2 *dev = usb_get_intfdata(intf); + + return sprintf(buf, "%d", dev->net_count); +} +static DEVICE_ATTR(nets, S_IRUGO, show_nets, NULL); + +static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg) +{ + int actual_length; + + return usb_bulk_msg(dev->udev, + usb_sndbulkpipe(dev->udev, 2), + msg, + msg->msg.hdr.len << 2, + &actual_length, + 1000); +} + +static int esd_usb2_wait_msg(struct esd_usb2 *dev, + struct esd_usb2_msg *msg) +{ + int actual_length; + + return usb_bulk_msg(dev->udev, + usb_rcvbulkpipe(dev->udev, 1), + msg, + sizeof(*msg), + &actual_length, + 1000); +} + +static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev) +{ + int i, err = 0; + + if (dev->rxinitdone) + return 0; + + for (i = 0; i < MAX_RX_URBS; i++) { + struct urb *urb = NULL; + u8 *buf = NULL; + + /* create a URB, and a buffer for it */ + urb = usb_alloc_urb(0, GFP_KERNEL); + if (!urb) { + dev_warn(dev->udev->dev.parent, + "No memory left for URBs\n"); + err = -ENOMEM; + break; + } + + buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL, + &urb->transfer_dma); + if (!buf) { + dev_warn(dev->udev->dev.parent, + "No memory left for USB buffer\n"); + err = -ENOMEM; + goto freeurb; + } + + usb_fill_bulk_urb(urb, dev->udev, + usb_rcvbulkpipe(dev->udev, 1), + buf, RX_BUFFER_SIZE, + esd_usb2_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); + } + +freeurb: + /* Drop reference, USB core will take care of freeing it */ + usb_free_urb(urb); + if (err) + break; + } + + /* Did we submit any URBs */ + if (i == 0) { + dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n"); + return err; + } + + /* Warn if we've couldn't transmit all the URBs */ + if (i < MAX_RX_URBS) { + dev_warn(dev->udev->dev.parent, + "rx performance may be slow\n"); + } + + dev->rxinitdone = 1; + return 0; +} + +/* + * Start interface + */ +static int esd_usb2_start(struct esd_usb2_net_priv *priv) +{ + struct esd_usb2 *dev = priv->usb2; + struct net_device *netdev = priv->netdev; + struct esd_usb2_msg msg; + int err, i; + + /* + * Enable all IDs + * The IDADD message takes up to 64 32 bit bitmasks (2048 bits). + * Each bit represents one 11 bit CAN identifier. A set bit + * enables reception of the corresponding CAN identifier. A cleared + * bit disabled this identifier. An additional bitmask value + * following the CAN 2.0A bits is used to enable reception of + * extended CAN frames. Only the LSB of this final mask is checked + * for the complete 29 bit ID range. The IDADD message also allows + * filter configuration for an ID subset. In this case you can add + * the number of the starting bitmask (0..64) to the filter.option + * field followed by only some bitmasks. + */ + msg.msg.hdr.cmd = CMD_IDADD; + msg.msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT; + msg.msg.filter.net = priv->index; + msg.msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */ + for (i = 0; i < ESD_MAX_ID_SEGMENT; i++) + msg.msg.filter.mask[i] = cpu_to_le32(0xffffffff); + /* enable 29bit extended IDs */ + msg.msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001); + + err = esd_usb2_send_msg(dev, &msg); + if (err) + goto failed; + + err = esd_usb2_setup_rx_urbs(dev); + if (err) + goto failed; + + priv->can.state = CAN_STATE_ERROR_ACTIVE; + + return 0; + +failed: + if (err == -ENODEV) + netif_device_detach(netdev); + + dev_err(netdev->dev.parent, "couldn't start device: %d\n", err); + + return err; +} + +static void unlink_all_urbs(struct esd_usb2 *dev) +{ + struct esd_usb2_net_priv *priv; + int i; + + usb_kill_anchored_urbs(&dev->rx_submitted); + for (i = 0; i < dev->net_count; i++) { + priv = dev->nets[i]; + if (priv) { + usb_kill_anchored_urbs(&priv->tx_submitted); + atomic_set(&priv->active_tx_jobs, 0); + + for (i = 0; i < MAX_TX_URBS; i++) + priv->tx_contexts[i].echo_index = MAX_TX_URBS; + } + } +} + +static int esd_usb2_open(struct net_device *netdev) +{ + struct esd_usb2_net_priv *priv = netdev_priv(netdev); + int err; + + /* common open */ + err = open_candev(netdev); + if (err) + return err; + + /* finally start device */ + err = esd_usb2_start(priv); + if (err) { + dev_warn(netdev->dev.parent, + "couldn't start device: %d\n", err); + close_candev(netdev); + return err; + } + + priv->open_time = jiffies; + + netif_start_queue(netdev); + + return 0; +} + +static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb, + struct net_device *netdev) +{ + struct esd_usb2_net_priv *priv = netdev_priv(netdev); + struct esd_usb2 *dev = priv->usb2; + struct esd_tx_urb_context *context = NULL; + struct net_device_stats *stats = &netdev->stats; + struct can_frame *cf = (struct can_frame *)skb->data; + struct esd_usb2_msg *msg; + struct urb *urb; + u8 *buf; + int i, err; + int ret = NETDEV_TX_OK; + size_t size = sizeof(struct esd_usb2_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) { + dev_err(netdev->dev.parent, "No memory left for URBs\n"); + stats->tx_dropped++; + dev_kfree_skb(skb); + goto nourbmem; + } + + buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, + &urb->transfer_dma); + if (!buf) { + dev_err(netdev->dev.parent, "No memory left for USB buffer\n"); + stats->tx_dropped++; + dev_kfree_skb(skb); + goto nobufmem; + } + + msg = (struct esd_usb2_msg *)buf; + + msg->msg.hdr.len = 3; /* minimal length */ + msg->msg.hdr.cmd = CMD_CAN_TX; + msg->msg.tx.net = priv->index; + msg->msg.tx.dlc = cf->can_dlc; + msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK); + + if (cf->can_id & CAN_RTR_FLAG) + msg->msg.tx.dlc |= ESD_RTR; + + if (cf->can_id & CAN_EFF_FLAG) + msg->msg.tx.id |= cpu_to_le32(ESD_EXTID); + + for (i = 0; i < cf->can_dlc; i++) + msg->msg.tx.data[i] = cf->data[i]; + + msg->msg.hdr.len += (cf->can_dlc + 3) >> 2; + + for (i = 0; i < MAX_TX_URBS; i++) { + if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { + context = &priv->tx_contexts[i]; + break; + } + } + + /* + * This may never happen. + */ + if (!context) { + dev_warn(netdev->dev.parent, "couldn't find free context\n"); + ret = NETDEV_TX_BUSY; + goto releasebuf; + } + + context->priv = priv; + context->echo_index = i; + context->dlc = cf->can_dlc; + + /* hnd must not be 0 - MSB is stripped in txdone handling */ + msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */ + + usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf, + msg->msg.hdr.len << 2, + esd_usb2_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_jobs); + + /* Slow down tx path */ + if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS) + netif_stop_queue(netdev); + + err = usb_submit_urb(urb, GFP_ATOMIC); + if (err) { + can_free_echo_skb(netdev, context->echo_index); + + atomic_dec(&priv->active_tx_jobs); + usb_unanchor_urb(urb); + + stats->tx_dropped++; + + if (err == -ENODEV) + netif_device_detach(netdev); + else + dev_warn(netdev->dev.parent, "failed tx_urb %d\n", err); + + goto releasebuf; + } + + netdev->trans_start = jiffies; + + /* + * Release our reference to this URB, the USB core will eventually free + * it entirely. + */ + usb_free_urb(urb); + + return NETDEV_TX_OK; + +releasebuf: + usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); + +nobufmem: + usb_free_urb(urb); + +nourbmem: + return ret; +} + +static int esd_usb2_close(struct net_device *netdev) +{ + struct esd_usb2_net_priv *priv = netdev_priv(netdev); + struct esd_usb2_msg msg; + int i; + + /* Disable all IDs (see esd_usb2_start()) */ + msg.msg.hdr.cmd = CMD_IDADD; + msg.msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT; + msg.msg.filter.net = priv->index; + msg.msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */ + for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++) + msg.msg.filter.mask[i] = 0; + if (esd_usb2_send_msg(priv->usb2, &msg) < 0) + dev_err(netdev->dev.parent, "sending idadd message failed\n"); + + /* set CAN controller to reset mode */ + msg.msg.hdr.len = 2; + msg.msg.hdr.cmd = CMD_SETBAUD; + msg.msg.setbaud.net = priv->index; + msg.msg.setbaud.rsvd = 0; + msg.msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE); + if (esd_usb2_send_msg(priv->usb2, &msg) < 0) + dev_err(netdev->dev.parent, "sending setbaud message failed\n"); + + priv->can.state = CAN_STATE_STOPPED; + + netif_stop_queue(netdev); + + close_candev(netdev); + + priv->open_time = 0; + + return 0; +} + +static const struct net_device_ops esd_usb2_netdev_ops = { + .ndo_open = esd_usb2_open, + .ndo_stop = esd_usb2_close, + .ndo_start_xmit = esd_usb2_start_xmit, +}; + +static struct can_bittiming_const esd_usb2_bittiming_const = { + .name = "esd_usb2", + .tseg1_min = ESD_USB2_TSEG1_MIN, + .tseg1_max = ESD_USB2_TSEG1_MAX, + .tseg2_min = ESD_USB2_TSEG2_MIN, + .tseg2_max = ESD_USB2_TSEG2_MAX, + .sjw_max = ESD_USB2_SJW_MAX, + .brp_min = ESD_USB2_BRP_MIN, + .brp_max = ESD_USB2_BRP_MAX, + .brp_inc = ESD_USB2_BRP_INC, +}; + +static int esd_usb2_set_bittiming(struct net_device *netdev) +{ + struct esd_usb2_net_priv *priv = netdev_priv(netdev); + struct can_bittiming *bt = &priv->can.bittiming; + struct esd_usb2_msg msg; + u32 canbtr; + + canbtr = ESD_USB2_UBR; + canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1); + canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1)) + << ESD_USB2_SJW_SHIFT; + canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1) + & (ESD_USB2_TSEG1_MAX - 1)) + << ESD_USB2_TSEG1_SHIFT; + canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1)) + << ESD_USB2_TSEG2_SHIFT; + if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) + canbtr |= ESD_USB2_3_SAMPLES; + + msg.msg.hdr.len = 2; + msg.msg.hdr.cmd = CMD_SETBAUD; + msg.msg.setbaud.net = priv->index; + msg.msg.setbaud.rsvd = 0; + msg.msg.setbaud.baud = cpu_to_le32(canbtr); + + dev_info(netdev->dev.parent, "setting BTR=%#x\n", canbtr); + + return esd_usb2_send_msg(priv->usb2, &msg); +} + +static int esd_usb2_get_berr_counter(const struct net_device *netdev, + struct can_berr_counter *bec) +{ + struct esd_usb2_net_priv *priv = netdev_priv(netdev); + + bec->txerr = priv->bec.txerr; + bec->rxerr = priv->bec.rxerr; + + return 0; +} + +static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode) +{ + struct esd_usb2_net_priv *priv = netdev_priv(netdev); + + if (!priv->open_time) + return -EINVAL; + + switch (mode) { + case CAN_MODE_START: + netif_wake_queue(netdev); + break; + + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int esd_usb2_probe_one_net(struct usb_interface *intf, int index) +{ + struct esd_usb2 *dev = usb_get_intfdata(intf); + struct net_device *netdev; + struct esd_usb2_net_priv *priv; + int err = 0; + int i; + + netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS); + if (!netdev) { + dev_err(&intf->dev, "couldn't alloc candev\n"); + err = -ENOMEM; + goto done; + } + + priv = netdev_priv(netdev); + + init_usb_anchor(&priv->tx_submitted); + atomic_set(&priv->active_tx_jobs, 0); + + for (i = 0; i < MAX_TX_URBS; i++) + priv->tx_contexts[i].echo_index = MAX_TX_URBS; + + priv->usb2 = dev; + priv->netdev = netdev; + priv->index = index; + + priv->can.state = CAN_STATE_STOPPED; + priv->can.clock.freq = ESD_USB2_CAN_CLOCK; + priv->can.bittiming_const = &esd_usb2_bittiming_const; + priv->can.do_set_bittiming = esd_usb2_set_bittiming; + priv->can.do_set_mode = esd_usb2_set_mode; + priv->can.do_get_berr_counter = esd_usb2_get_berr_counter; + priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; + + netdev->flags |= IFF_ECHO; /* we support local echo */ + + netdev->netdev_ops = &esd_usb2_netdev_ops; + + SET_NETDEV_DEV(netdev, &intf->dev); + + err = register_candev(netdev); + if (err) { + dev_err(&intf->dev, + "couldn't register CAN device: %d\n", err); + free_candev(netdev); + err = -ENOMEM; + goto done; + } + + dev->nets[index] = priv; + dev_info(netdev->dev.parent, "device %s registered\n", netdev->name); + +done: + return err; +} + +/* + * probe function for new USB2 devices + * + * check version information and number of available + * CAN interfaces + */ +static int esd_usb2_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct esd_usb2 *dev; + struct esd_usb2_msg msg; + int i, err; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) { + err = -ENOMEM; + goto done; + } + + dev->udev = interface_to_usbdev(intf); + + init_usb_anchor(&dev->rx_submitted); + + usb_set_intfdata(intf, dev); + + /* query number of CAN interfaces (nets) */ + msg.msg.hdr.cmd = CMD_VERSION; + msg.msg.hdr.len = 2; + msg.msg.version.rsvd = 0; + msg.msg.version.flags = 0; + msg.msg.version.drv_version = 0; + + err = esd_usb2_send_msg(dev, &msg); + if (err < 0) { + dev_err(&intf->dev, "sending version message failed\n"); + goto free_dev; + } + + err = esd_usb2_wait_msg(dev, &msg); + if (err < 0) { + dev_err(&intf->dev, "no version message answer\n"); + goto free_dev; + } + + dev->net_count = (int)msg.msg.version_reply.nets; + dev->version = le32_to_cpu(msg.msg.version_reply.version); + + if (device_create_file(&intf->dev, &dev_attr_firmware)) + dev_err(&intf->dev, + "Couldn't create device file for firmware\n"); + + if (device_create_file(&intf->dev, &dev_attr_hardware)) + dev_err(&intf->dev, + "Couldn't create device file for hardware\n"); + + if (device_create_file(&intf->dev, &dev_attr_nets)) + dev_err(&intf->dev, + "Couldn't create device file for nets\n"); + + /* do per device probing */ + for (i = 0; i < dev->net_count; i++) + esd_usb2_probe_one_net(intf, i); + + return 0; + +free_dev: + kfree(dev); +done: + return err; +} + +/* + * called by the usb core when the device is removed from the system + */ +static void esd_usb2_disconnect(struct usb_interface *intf) +{ + struct esd_usb2 *dev = usb_get_intfdata(intf); + struct net_device *netdev; + int i; + + device_remove_file(&intf->dev, &dev_attr_firmware); + device_remove_file(&intf->dev, &dev_attr_hardware); + device_remove_file(&intf->dev, &dev_attr_nets); + + usb_set_intfdata(intf, NULL); + + if (dev) { + for (i = 0; i < dev->net_count; i++) { + if (dev->nets[i]) { + netdev = dev->nets[i]->netdev; + unregister_netdev(netdev); + free_candev(netdev); + } + } + unlink_all_urbs(dev); + } +} + +/* usb specific object needed to register this driver with the usb subsystem */ +static struct usb_driver esd_usb2_driver = { + .name = "esd_usb2", + .probe = esd_usb2_probe, + .disconnect = esd_usb2_disconnect, + .id_table = esd_usb2_table, +}; + +static int __init esd_usb2_init(void) +{ + int err; + + /* register this driver with the USB subsystem */ + err = usb_register(&esd_usb2_driver); + + if (err) { + err("usb_register failed. Error number %d\n", err); + return err; + } + + return 0; +} +module_init(esd_usb2_init); + +static void __exit esd_usb2_exit(void) +{ + /* deregister this driver with the USB subsystem */ + usb_deregister(&esd_usb2_driver); +} +module_exit(esd_usb2_exit); |