/*
* theory of operation:
*
* priv->tx_echo holds the number of the oldest can_frame put for
* transmission into the hardware, but not yet ACKed by the CAN tx
* complete IRQ.
*
* We iterate from priv->tx_echo to priv->tx_next and check if the
* packet has been transmitted, echo it back to the CAN framework.
* If we discover a not yet transmitted package, stop looking for more.
*/
static void c_can_do_tx(struct net_device *dev)
{
u32 val;
u32 msg_obj_no;
struct c_can_priv *priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
for (/* nix */; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) {
msg_obj_no = get_tx_echo_msg_obj(priv);
val = c_can_read_reg32(priv, &priv->regs->txrqst1);
if (!(val & (1 << msg_obj_no))) {
can_get_echo_skb(dev,
msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST);
stats->tx_bytes += priv->read_reg(priv,
&priv->regs->ifregs[0].msg_cntrl)
& IF_MCONT_DLC_MASK;
stats->tx_packets++;
c_can_inval_msg_object(dev, 0, msg_obj_no);
}
}
/* restart queue if wrap-up or if queue stalled on last pkt */
if (((priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) != 0) ||
((priv->tx_echo & C_CAN_NEXT_MSG_OBJ_MASK) == 0))
netif_wake_queue(dev);
}
/*
* theory of operation:
*
* priv->tx_echo holds the number of the oldest can_frame put for
* transmission into the hardware, but not yet ACKed by the CAN tx
* complete IRQ.
*
* We iterate from priv->tx_echo to priv->tx_next and check if the
* packet has been transmitted, echo it back to the CAN framework.
* If we discover a not yet transmitted packet, stop looking for more.
*/
static void c_can_do_tx(struct net_device *dev)
{
u32 val;
u32 msg_obj_no;
struct c_can_priv *priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
for (/* nix */; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) {
msg_obj_no = get_tx_echo_msg_obj(priv);
val = c_can_read_reg32(priv, C_CAN_TXRQST1_REG);
if (!(val & (1 << (msg_obj_no - 1)))) {
can_get_echo_skb(dev,
msg_obj_no - C_CAN_MSG_OBJ_TX_FIRST);
stats->tx_bytes += priv->read_reg(priv,
C_CAN_IFACE(MSGCTRL_REG, 0))
& IF_MCONT_DLC_MASK;
stats->tx_packets++;
can_led_event(dev, CAN_LED_EVENT_TX);
c_can_inval_msg_object(dev, 0, msg_obj_no);
} else {
break;
}
}
/* restart queue if wrap-up or if queue stalled on last pkt */
if (((priv->tx_next & C_CAN_NEXT_MSG_OBJ_MASK) != 0) ||
((priv->tx_echo & C_CAN_NEXT_MSG_OBJ_MASK) == 0))
netif_wake_queue(dev);
}
/*
* 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;
}
static void c_can_do_tx(struct net_device *dev)
{
struct c_can_priv *priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
u32 idx, obj, pkts = 0, bytes = 0, pend, clr;
clr = pend = priv->read_reg(priv, C_CAN_INTPND2_REG);
while ((idx = ffs(pend))) {
idx--;
pend &= ~(1 << idx);
obj = idx + C_CAN_MSG_OBJ_TX_FIRST;
c_can_inval_tx_object(dev, IF_RX, obj);
can_get_echo_skb(dev, idx);
bytes += priv->dlc[idx];
pkts++;
}
/* Clear the bits in the tx_active mask */
atomic_sub(clr, &priv->tx_active);
if (clr & (1 << (C_CAN_MSG_OBJ_TX_NUM - 1)))
netif_wake_queue(dev);
if (pkts) {
stats->tx_bytes += bytes;
stats->tx_packets += pkts;
can_led_event(dev, CAN_LED_EVENT_TX);
}
}
/* Let priv->eskbp catch up to regs->txrd and echo back the skbs if echo
* is true and free them otherwise.
*
* If budget is >= 0, stop after handling at most budget skbs. Otherwise,
* continue until priv->eskbp catches up to regs->txrd.
*
* priv->lock *must* be held when calling this function
*/
static int catch_up_echo_skb(struct net_device *dev, int budget, bool echo)
{
struct grcan_priv *priv = netdev_priv(dev);
struct grcan_registers __iomem *regs = priv->regs;
struct grcan_dma *dma = &priv->dma;
struct net_device_stats *stats = &dev->stats;
int i, work_done;
/* Updates to priv->eskbp and wake-ups of the queue needs to
* be atomic towards the reads of priv->eskbp and shut-downs
* of the queue in grcan_start_xmit.
*/
u32 txrd = grcan_read_reg(®s->txrd);
for (work_done = 0; work_done < budget || budget < 0; work_done++) {
if (priv->eskbp == txrd)
break;
i = priv->eskbp / GRCAN_MSG_SIZE;
if (echo) {
/* Normal echo of messages */
stats->tx_packets++;
stats->tx_bytes += priv->txdlc[i];
priv->txdlc[i] = 0;
can_get_echo_skb(dev, i);
} else {
/* For cleanup of untransmitted messages */
can_free_echo_skb(dev, i);
}
priv->eskbp = grcan_ring_add(priv->eskbp, GRCAN_MSG_SIZE,
dma->tx.size);
txrd = grcan_read_reg(®s->txrd);
}
return work_done;
}
irqreturn_t omapl_tx_can_intr(int irq, void *dev_id)
{
struct net_device *ndev = dev_id;
struct omapl_pru_can_priv *priv = netdev_priv(ndev);
struct net_device_stats *stats = &ndev->stats;
u32 bit_set, mbxno;
pru_can_get_interrupt_status(&priv->can_tx_hndl);
if ((PRU_CAN_ISR_BIT_CCI & priv->can_tx_hndl.u32interruptstatus)
|| (PRU_CAN_ISR_BIT_SRDI & priv->can_tx_hndl.u32interruptstatus)) {
__can_debug("tx_int_status = 0x%X\n",
priv->can_tx_hndl.u32interruptstatus);
can_free_echo_skb(ndev, 0);
} else {
for (bit_set = 0; ((priv->can_tx_hndl.u32interruptstatus
& 0xFF) >> bit_set != 0); bit_set++) ;
if (0 == bit_set) {
__can_err("%s: invalid mailbox number\n", __func__);
can_free_echo_skb(ndev, 0);
} else {
mbxno = bit_set - 1; /* mail box numbering starts from 0 */
if (PRU_CAN_ISR_BIT_ESI & priv->can_tx_hndl.
u32interruptstatus) {
/* read gsr and ack pru */
pru_can_get_global_status(&priv->can_tx_hndl);
omapl_pru_can_err(ndev,
priv->can_tx_hndl.
u32interruptstatus,
priv->can_tx_hndl.
u32globalstatus);
} else {
stats->tx_packets++;
/* stats->tx_bytes += dlc; */
//can_//get_echo_skb(ndev, 0);
}
}
}
if (netif_queue_stopped(ndev))
netif_wake_queue(ndev);
can_get_echo_skb(ndev, 0);
pru_can_transfer_mode_set(true, ecanreceive);
return IRQ_HANDLED;
}
/* 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;
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 -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) {
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_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;
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);
usb_free_urb(urb);
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;
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);
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 = kzalloc(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_cmd_msg_buffer;
}
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_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 <*****@*****.**>");
MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
MODULE_LICENSE("GPL v2");
static irqreturn_t ti_hecc_interrupt(int irq, void *dev_id)
{
struct net_device *ndev = (struct net_device *)dev_id;
struct ti_hecc_priv *priv = netdev_priv(ndev);
struct net_device_stats *stats = &ndev->stats;
u32 mbxno, mbx_mask, int_status, err_status;
unsigned long ack, flags;
int_status = hecc_read(priv,
(priv->int_line) ? HECC_CANGIF1 : HECC_CANGIF0);
if (!int_status)
return IRQ_NONE;
err_status = hecc_read(priv, HECC_CANES);
if (err_status & (HECC_BUS_ERROR | HECC_CANES_BO |
HECC_CANES_EP | HECC_CANES_EW))
ti_hecc_error(ndev, int_status, err_status);
if (int_status & HECC_CANGIF_GMIF) {
while (priv->tx_tail - priv->tx_head > 0) {
mbxno = get_tx_tail_mb(priv);
mbx_mask = BIT(mbxno);
if (!(mbx_mask & hecc_read(priv, HECC_CANTA)))
break;
hecc_clear_bit(priv, HECC_CANMIM, mbx_mask);
hecc_write(priv, HECC_CANTA, mbx_mask);
spin_lock_irqsave(&priv->mbx_lock, flags);
hecc_clear_bit(priv, HECC_CANME, mbx_mask);
spin_unlock_irqrestore(&priv->mbx_lock, flags);
stats->tx_bytes += hecc_read_mbx(priv, mbxno,
HECC_CANMCF) & 0xF;
stats->tx_packets++;
can_get_echo_skb(ndev, mbxno);
--priv->tx_tail;
}
/* restart queue if wrap-up or if queue stalled on last pkt */
if (((priv->tx_head == priv->tx_tail) &&
((priv->tx_head & HECC_TX_MASK) != HECC_TX_MASK)) ||
(((priv->tx_tail & HECC_TX_MASK) == HECC_TX_MASK) &&
((priv->tx_head & HECC_TX_MASK) == HECC_TX_MASK)))
netif_wake_queue(ndev);
/* Disable RX mailbox interrupts and let NAPI reenable them */
if (hecc_read(priv, HECC_CANRMP)) {
ack = hecc_read(priv, HECC_CANMIM);
ack &= BIT(HECC_MAX_TX_MBOX) - 1;
hecc_write(priv, HECC_CANMIM, ack);
napi_schedule(&priv->napi);
}
}
/* clear all interrupt conditions - read back to avoid spurious ints */
if (priv->int_line) {
hecc_write(priv, HECC_CANGIF1, HECC_SET_REG);
int_status = hecc_read(priv, HECC_CANGIF1);
} else {
hecc_write(priv, HECC_CANGIF0, HECC_SET_REG);
int_status = hecc_read(priv, HECC_CANGIF0);
}
return IRQ_HANDLED;
}
static void gs_usb_receive_bulk_callback(struct urb *urb)
{
struct gs_usb *usbcan = urb->context;
struct gs_can *dev;
struct net_device *netdev;
int rc;
struct net_device_stats *stats;
struct gs_host_frame *hf = urb->transfer_buffer;
struct gs_tx_context *txc;
struct can_frame *cf;
struct sk_buff *skb;
BUG_ON(!usbcan);
switch (urb->status) {
case 0: /* success */
break;
case -ENOENT:
case -ESHUTDOWN:
return;
default:
/* do not resubmit aborted urbs. eg: when device goes down */
return;
}
/* device reports out of range channel id */
if (hf->channel >= GS_MAX_INTF)
goto resubmit_urb;
dev = usbcan->canch[hf->channel];
netdev = dev->netdev;
stats = &netdev->stats;
if (!netif_device_present(netdev))
return;
if (hf->echo_id == -1) { /* normal rx */
skb = alloc_can_skb(dev->netdev, &cf);
if (!skb)
return;
cf->can_id = hf->can_id;
cf->can_dlc = get_can_dlc(hf->can_dlc);
memcpy(cf->data, hf->data, 8);
/* ERROR frames tell us information about the controller */
if (hf->can_id & CAN_ERR_FLAG)
gs_update_state(dev, cf);
netdev->stats.rx_packets++;
netdev->stats.rx_bytes += hf->can_dlc;
netif_rx(skb);
} else { /* echo_id == hf->echo_id */
if (hf->echo_id >= GS_MAX_TX_URBS) {
netdev_err(netdev,
"Unexpected out of range echo id %d\n",
hf->echo_id);
goto resubmit_urb;
}
netdev->stats.tx_packets++;
netdev->stats.tx_bytes += hf->can_dlc;
txc = gs_get_tx_context(dev, hf->echo_id);
/* bad devices send bad echo_ids. */
if (!txc) {
netdev_err(netdev,
"Unexpected unused echo id %d\n",
hf->echo_id);
goto resubmit_urb;
}
can_get_echo_skb(netdev, hf->echo_id);
gs_free_tx_context(txc);
netif_wake_queue(netdev);
}
if (hf->flags & GS_CAN_FLAG_OVERFLOW) {
skb = alloc_can_err_skb(netdev, &cf);
if (!skb)
goto resubmit_urb;
cf->can_id |= CAN_ERR_CRTL;
cf->can_dlc = CAN_ERR_DLC;
cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
stats->rx_over_errors++;
stats->rx_errors++;
netif_rx(skb);
}
resubmit_urb:
usb_fill_bulk_urb(urb,
usbcan->udev,
usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN),
hf,
sizeof(struct gs_host_frame),
gs_usb_receive_bulk_callback,
usbcan
);
rc = usb_submit_urb(urb, GFP_ATOMIC);
/* USB failure take down all interfaces */
if (rc == -ENODEV) {
for (rc = 0; rc < GS_MAX_INTF; rc++) {
if (usbcan->canch[rc])
netif_device_detach(usbcan->canch[rc]->netdev);
}
}
}
