2 * CAN driver for EMS Dr. Thomas Wuensche CPC-USB/ARM7
4 * Copyright (C) 2004-2009 EMS Dr. Thomas Wuensche
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published
8 * by the Free Software Foundation; version 2 of the License.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 #include <linux/signal.h>
20 #include <linux/slab.h>
21 #include <linux/module.h>
22 #include <linux/netdevice.h>
23 #include <linux/usb.h>
25 #include <linux/can.h>
26 #include <linux/can/dev.h>
27 #include <linux/can/error.h>
29 MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
30 MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
31 MODULE_LICENSE("GPL v2");
33 /* Control-Values for CPC_Control() Command Subject Selection */
34 #define CONTR_CAN_MESSAGE 0x04
35 #define CONTR_CAN_STATE 0x0C
36 #define CONTR_BUS_ERROR 0x1C
38 /* Control Command Actions */
39 #define CONTR_CONT_OFF 0
40 #define CONTR_CONT_ON 1
43 /* Messages from CPC to PC */
44 #define CPC_MSG_TYPE_CAN_FRAME 1 /* CAN data frame */
45 #define CPC_MSG_TYPE_RTR_FRAME 8 /* CAN remote frame */
46 #define CPC_MSG_TYPE_CAN_PARAMS 12 /* Actual CAN parameters */
47 #define CPC_MSG_TYPE_CAN_STATE 14 /* CAN state message */
48 #define CPC_MSG_TYPE_EXT_CAN_FRAME 16 /* Extended CAN data frame */
49 #define CPC_MSG_TYPE_EXT_RTR_FRAME 17 /* Extended remote frame */
50 #define CPC_MSG_TYPE_CONTROL 19 /* change interface behavior */
51 #define CPC_MSG_TYPE_CONFIRM 20 /* command processed confirmation */
52 #define CPC_MSG_TYPE_OVERRUN 21 /* overrun events */
53 #define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */
54 #define CPC_MSG_TYPE_ERR_COUNTER 25 /* RX/TX error counter */
56 /* Messages from the PC to the CPC interface */
57 #define CPC_CMD_TYPE_CAN_FRAME 1 /* CAN data frame */
58 #define CPC_CMD_TYPE_CONTROL 3 /* control of interface behavior */
59 #define CPC_CMD_TYPE_CAN_PARAMS 6 /* set CAN parameters */
60 #define CPC_CMD_TYPE_RTR_FRAME 13 /* CAN remote frame */
61 #define CPC_CMD_TYPE_CAN_STATE 14 /* CAN state message */
62 #define CPC_CMD_TYPE_EXT_CAN_FRAME 15 /* Extended CAN data frame */
63 #define CPC_CMD_TYPE_EXT_RTR_FRAME 16 /* Extended CAN remote frame */
64 #define CPC_CMD_TYPE_CAN_EXIT 200 /* exit the CAN */
66 #define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */
67 #define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8 /* clear CPC_MSG queue */
68 #define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */
70 #define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */
72 #define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */
75 #define CPC_OVR_EVENT_CAN 0x01
76 #define CPC_OVR_EVENT_CANSTATE 0x02
77 #define CPC_OVR_EVENT_BUSERROR 0x04
80 * If the CAN controller lost a message we indicate it with the highest bit
81 * set in the count field.
83 #define CPC_OVR_HW 0x80
85 /* Size of the "struct ems_cpc_msg" without the union */
86 #define CPC_MSG_HEADER_LEN 11
87 #define CPC_CAN_MSG_MIN_SIZE 5
89 /* Define these values to match your devices */
90 #define USB_CPCUSB_VENDOR_ID 0x12D6
92 #define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444
94 /* Mode register NXP LPC2119/SJA1000 CAN Controller */
95 #define SJA1000_MOD_NORMAL 0x00
96 #define SJA1000_MOD_RM 0x01
98 /* ECC register NXP LPC2119/SJA1000 CAN Controller */
99 #define SJA1000_ECC_SEG 0x1F
100 #define SJA1000_ECC_DIR 0x20
101 #define SJA1000_ECC_ERR 0x06
102 #define SJA1000_ECC_BIT 0x00
103 #define SJA1000_ECC_FORM 0x40
104 #define SJA1000_ECC_STUFF 0x80
105 #define SJA1000_ECC_MASK 0xc0
107 /* Status register content */
108 #define SJA1000_SR_BS 0x80
109 #define SJA1000_SR_ES 0x40
111 #define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA
114 * The device actually uses a 16MHz clock to generate the CAN clock
115 * but it expects SJA1000 bit settings based on 8MHz (is internally
118 #define EMS_USB_ARM7_CLOCK 8000000
121 * CAN-Message representation in a CPC_MSG. Message object type is
122 * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or
123 * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME.
131 /* Representation of the CAN parameters for the SJA1000 controller */
132 struct cpc_sja1000_params {
147 /* CAN params message representation */
148 struct cpc_can_params {
151 /* Will support M16C CAN controller in the future */
153 struct cpc_sja1000_params sja1000;
157 /* Structure for confirmed message handling */
159 u8 error; /* error code */
162 /* Structure for overrun conditions */
168 /* SJA1000 CAN errors (compatible to NXP LPC2119) */
169 struct cpc_sja1000_can_error {
175 /* structure for CAN error conditions */
176 struct cpc_can_error {
182 /* Other controllers may also provide error code capture regs */
184 struct cpc_sja1000_can_error sja1000;
190 * Structure containing RX/TX error counter. This structure is used to request
191 * the values of the CAN controllers TX and RX error counter.
193 struct cpc_can_err_counter {
198 /* Main message type used between library and application */
199 struct __packed ems_cpc_msg {
200 u8 type; /* type of message */
201 u8 length; /* length of data within union 'msg' */
202 u8 msgid; /* confirmation handle */
203 __le32 ts_sec; /* timestamp in seconds */
204 __le32 ts_nsec; /* timestamp in nano seconds */
208 struct cpc_can_msg can_msg;
209 struct cpc_can_params can_params;
210 struct cpc_confirm confirmation;
211 struct cpc_overrun overrun;
212 struct cpc_can_error error;
213 struct cpc_can_err_counter err_counter;
219 * Table of devices that work with this driver
220 * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet.
222 static struct usb_device_id ems_usb_table[] = {
223 {USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
224 {} /* Terminating entry */
227 MODULE_DEVICE_TABLE(usb, ems_usb_table);
229 #define RX_BUFFER_SIZE 64
230 #define CPC_HEADER_SIZE 4
231 #define INTR_IN_BUFFER_SIZE 4
233 #define MAX_RX_URBS 10
234 #define MAX_TX_URBS 10
238 struct ems_tx_urb_context {
246 struct can_priv can; /* must be the first member */
248 struct sk_buff *echo_skb[MAX_TX_URBS];
250 struct usb_device *udev;
251 struct net_device *netdev;
253 atomic_t active_tx_urbs;
254 struct usb_anchor tx_submitted;
255 struct ems_tx_urb_context tx_contexts[MAX_TX_URBS];
257 struct usb_anchor rx_submitted;
259 struct urb *intr_urb;
264 unsigned int free_slots; /* remember number of available slots */
266 struct ems_cpc_msg active_params; /* active controller parameters */
269 static void ems_usb_read_interrupt_callback(struct urb *urb)
271 struct ems_usb *dev = urb->context;
272 struct net_device *netdev = dev->netdev;
275 if (!netif_device_present(netdev))
278 switch (urb->status) {
280 dev->free_slots = dev->intr_in_buffer[1];
283 case -ECONNRESET: /* unlink */
289 netdev_info(netdev, "Rx interrupt aborted %d\n", urb->status);
293 err = usb_submit_urb(urb, GFP_ATOMIC);
296 netif_device_detach(netdev);
298 netdev_err(netdev, "failed resubmitting intr urb: %d\n", err);
301 static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
303 struct can_frame *cf;
306 struct net_device_stats *stats = &dev->netdev->stats;
308 skb = alloc_can_skb(dev->netdev, &cf);
312 cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
313 cf->can_dlc = get_can_dlc(msg->msg.can_msg.length & 0xF);
315 if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME ||
316 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
317 cf->can_id |= CAN_EFF_FLAG;
319 if (msg->type == CPC_MSG_TYPE_RTR_FRAME ||
320 msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
321 cf->can_id |= CAN_RTR_FLAG;
323 for (i = 0; i < cf->can_dlc; i++)
324 cf->data[i] = msg->msg.can_msg.msg[i];
328 stats->rx_bytes += cf->can_dlc;
332 static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
334 struct can_frame *cf;
336 struct net_device_stats *stats = &dev->netdev->stats;
338 skb = alloc_can_err_skb(dev->netdev, &cf);
342 if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
343 u8 state = msg->msg.can_state;
345 if (state & SJA1000_SR_BS) {
346 dev->can.state = CAN_STATE_BUS_OFF;
347 cf->can_id |= CAN_ERR_BUSOFF;
349 dev->can.can_stats.bus_off++;
350 can_bus_off(dev->netdev);
351 } else if (state & SJA1000_SR_ES) {
352 dev->can.state = CAN_STATE_ERROR_WARNING;
353 dev->can.can_stats.error_warning++;
355 dev->can.state = CAN_STATE_ERROR_ACTIVE;
356 dev->can.can_stats.error_passive++;
358 } else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
359 u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
360 u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
361 u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
363 /* bus error interrupt */
364 dev->can.can_stats.bus_error++;
367 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
369 switch (ecc & SJA1000_ECC_MASK) {
370 case SJA1000_ECC_BIT:
371 cf->data[2] |= CAN_ERR_PROT_BIT;
373 case SJA1000_ECC_FORM:
374 cf->data[2] |= CAN_ERR_PROT_FORM;
376 case SJA1000_ECC_STUFF:
377 cf->data[2] |= CAN_ERR_PROT_STUFF;
380 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
381 cf->data[3] = ecc & SJA1000_ECC_SEG;
385 /* Error occurred during transmission? */
386 if ((ecc & SJA1000_ECC_DIR) == 0)
387 cf->data[2] |= CAN_ERR_PROT_TX;
389 if (dev->can.state == CAN_STATE_ERROR_WARNING ||
390 dev->can.state == CAN_STATE_ERROR_PASSIVE) {
391 cf->data[1] = (txerr > rxerr) ?
392 CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
394 } else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
395 cf->can_id |= CAN_ERR_CRTL;
396 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
398 stats->rx_over_errors++;
403 stats->rx_bytes += cf->can_dlc;
408 * callback for bulk IN urb
410 static void ems_usb_read_bulk_callback(struct urb *urb)
412 struct ems_usb *dev = urb->context;
413 struct net_device *netdev;
416 netdev = dev->netdev;
418 if (!netif_device_present(netdev))
421 switch (urb->status) {
422 case 0: /* success */
429 netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status);
433 if (urb->actual_length > CPC_HEADER_SIZE) {
434 struct ems_cpc_msg *msg;
435 u8 *ibuf = urb->transfer_buffer;
438 msg_count = ibuf[0] & ~0x80;
440 start = CPC_HEADER_SIZE;
443 msg = (struct ems_cpc_msg *)&ibuf[start];
446 case CPC_MSG_TYPE_CAN_STATE:
447 /* Process CAN state changes */
448 ems_usb_rx_err(dev, msg);
451 case CPC_MSG_TYPE_CAN_FRAME:
452 case CPC_MSG_TYPE_EXT_CAN_FRAME:
453 case CPC_MSG_TYPE_RTR_FRAME:
454 case CPC_MSG_TYPE_EXT_RTR_FRAME:
455 ems_usb_rx_can_msg(dev, msg);
458 case CPC_MSG_TYPE_CAN_FRAME_ERROR:
459 /* Process errorframe */
460 ems_usb_rx_err(dev, msg);
463 case CPC_MSG_TYPE_OVERRUN:
464 /* Message lost while receiving */
465 ems_usb_rx_err(dev, msg);
469 start += CPC_MSG_HEADER_LEN + msg->length;
472 if (start > urb->transfer_buffer_length) {
473 netdev_err(netdev, "format error\n");
480 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
481 urb->transfer_buffer, RX_BUFFER_SIZE,
482 ems_usb_read_bulk_callback, dev);
484 retval = usb_submit_urb(urb, GFP_ATOMIC);
486 if (retval == -ENODEV)
487 netif_device_detach(netdev);
490 "failed resubmitting read bulk urb: %d\n", retval);
494 * callback for bulk IN urb
496 static void ems_usb_write_bulk_callback(struct urb *urb)
498 struct ems_tx_urb_context *context = urb->context;
500 struct net_device *netdev;
505 netdev = dev->netdev;
507 /* free up our allocated buffer */
508 usb_free_coherent(urb->dev, urb->transfer_buffer_length,
509 urb->transfer_buffer, urb->transfer_dma);
511 atomic_dec(&dev->active_tx_urbs);
513 if (!netif_device_present(netdev))
517 netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
519 netdev->trans_start = jiffies;
521 /* transmission complete interrupt */
522 netdev->stats.tx_packets++;
523 netdev->stats.tx_bytes += context->dlc;
525 can_get_echo_skb(netdev, context->echo_index);
527 /* Release context */
528 context->echo_index = MAX_TX_URBS;
530 if (netif_queue_stopped(netdev))
531 netif_wake_queue(netdev);
535 * Send the given CPC command synchronously
537 static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
542 memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
543 msg->length + CPC_MSG_HEADER_LEN);
546 memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
548 return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
549 &dev->tx_msg_buffer[0],
550 msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
551 &actual_length, 1000);
555 * Change CAN controllers' mode register
557 static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
559 dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
561 return ems_usb_command_msg(dev, &dev->active_params);
565 * Send a CPC_Control command to change behaviour when interface receives a CAN
566 * message, bus error or CAN state changed notifications.
568 static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
570 struct ems_cpc_msg cmd;
572 cmd.type = CPC_CMD_TYPE_CONTROL;
573 cmd.length = CPC_MSG_HEADER_LEN + 1;
577 cmd.msg.generic[0] = val;
579 return ems_usb_command_msg(dev, &cmd);
585 static int ems_usb_start(struct ems_usb *dev)
587 struct net_device *netdev = dev->netdev;
590 dev->intr_in_buffer[0] = 0;
591 dev->free_slots = 15; /* initial size */
593 for (i = 0; i < MAX_RX_URBS; i++) {
594 struct urb *urb = NULL;
597 /* create a URB, and a buffer for it */
598 urb = usb_alloc_urb(0, GFP_KERNEL);
600 netdev_err(netdev, "No memory left for URBs\n");
605 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
608 netdev_err(netdev, "No memory left for USB buffer\n");
614 usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
616 ems_usb_read_bulk_callback, dev);
617 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
618 usb_anchor_urb(urb, &dev->rx_submitted);
620 err = usb_submit_urb(urb, GFP_KERNEL);
622 usb_unanchor_urb(urb);
623 usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
629 /* Drop reference, USB core will take care of freeing it */
633 /* Did we submit any URBs */
635 netdev_warn(netdev, "couldn't setup read URBs\n");
639 /* Warn if we've couldn't transmit all the URBs */
641 netdev_warn(netdev, "rx performance may be slow\n");
643 /* Setup and start interrupt URB */
644 usb_fill_int_urb(dev->intr_urb, dev->udev,
645 usb_rcvintpipe(dev->udev, 1),
648 ems_usb_read_interrupt_callback, dev, 1);
650 err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
652 netdev_warn(netdev, "intr URB submit failed: %d\n", err);
657 /* CPC-USB will transfer received message to host */
658 err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
662 /* CPC-USB will transfer CAN state changes to host */
663 err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
667 /* CPC-USB will transfer bus errors to host */
668 err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
672 err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
676 dev->can.state = CAN_STATE_ERROR_ACTIVE;
681 netdev_warn(netdev, "couldn't submit control: %d\n", err);
686 static void unlink_all_urbs(struct ems_usb *dev)
690 usb_unlink_urb(dev->intr_urb);
692 usb_kill_anchored_urbs(&dev->rx_submitted);
694 usb_kill_anchored_urbs(&dev->tx_submitted);
695 atomic_set(&dev->active_tx_urbs, 0);
697 for (i = 0; i < MAX_TX_URBS; i++)
698 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
701 static int ems_usb_open(struct net_device *netdev)
703 struct ems_usb *dev = netdev_priv(netdev);
706 err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
711 err = open_candev(netdev);
715 /* finally start device */
716 err = ems_usb_start(dev);
719 netif_device_detach(dev->netdev);
721 netdev_warn(netdev, "couldn't start device: %d\n", err);
723 close_candev(netdev);
729 netif_start_queue(netdev);
734 static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
736 struct ems_usb *dev = netdev_priv(netdev);
737 struct ems_tx_urb_context *context = NULL;
738 struct net_device_stats *stats = &netdev->stats;
739 struct can_frame *cf = (struct can_frame *)skb->data;
740 struct ems_cpc_msg *msg;
744 size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
745 + sizeof(struct cpc_can_msg);
747 if (can_dropped_invalid_skb(netdev, skb))
750 /* create a URB, and a buffer for it, and copy the data to the URB */
751 urb = usb_alloc_urb(0, GFP_ATOMIC);
753 netdev_err(netdev, "No memory left for URBs\n");
757 buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
759 netdev_err(netdev, "No memory left for USB buffer\n");
764 msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
766 msg->msg.can_msg.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
767 msg->msg.can_msg.length = cf->can_dlc;
769 if (cf->can_id & CAN_RTR_FLAG) {
770 msg->type = cf->can_id & CAN_EFF_FLAG ?
771 CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
773 msg->length = CPC_CAN_MSG_MIN_SIZE;
775 msg->type = cf->can_id & CAN_EFF_FLAG ?
776 CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
778 for (i = 0; i < cf->can_dlc; i++)
779 msg->msg.can_msg.msg[i] = cf->data[i];
781 msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
784 for (i = 0; i < MAX_TX_URBS; i++) {
785 if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
786 context = &dev->tx_contexts[i];
792 * May never happen! When this happens we'd more URBs in flight as
793 * allowed (MAX_TX_URBS).
796 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
799 netdev_warn(netdev, "couldn't find free context\n");
801 return NETDEV_TX_BUSY;
805 context->echo_index = i;
806 context->dlc = cf->can_dlc;
808 usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
809 size, ems_usb_write_bulk_callback, context);
810 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
811 usb_anchor_urb(urb, &dev->tx_submitted);
813 can_put_echo_skb(skb, netdev, context->echo_index);
815 atomic_inc(&dev->active_tx_urbs);
817 err = usb_submit_urb(urb, GFP_ATOMIC);
819 can_free_echo_skb(netdev, context->echo_index);
821 usb_unanchor_urb(urb);
822 usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
825 atomic_dec(&dev->active_tx_urbs);
827 if (err == -ENODEV) {
828 netif_device_detach(netdev);
830 netdev_warn(netdev, "failed tx_urb %d\n", err);
835 netdev->trans_start = jiffies;
837 /* Slow down tx path */
838 if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
839 dev->free_slots < 5) {
840 netif_stop_queue(netdev);
845 * Release our reference to this URB, the USB core will eventually free
859 static int ems_usb_close(struct net_device *netdev)
861 struct ems_usb *dev = netdev_priv(netdev);
864 unlink_all_urbs(dev);
866 netif_stop_queue(netdev);
868 /* Set CAN controller to reset mode */
869 if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
870 netdev_warn(netdev, "couldn't stop device");
872 close_candev(netdev);
877 static const struct net_device_ops ems_usb_netdev_ops = {
878 .ndo_open = ems_usb_open,
879 .ndo_stop = ems_usb_close,
880 .ndo_start_xmit = ems_usb_start_xmit,
881 .ndo_change_mtu = can_change_mtu,
884 static const struct can_bittiming_const ems_usb_bittiming_const = {
896 static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
898 struct ems_usb *dev = netdev_priv(netdev);
902 if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
903 netdev_warn(netdev, "couldn't start device");
905 if (netif_queue_stopped(netdev))
906 netif_wake_queue(netdev);
916 static int ems_usb_set_bittiming(struct net_device *netdev)
918 struct ems_usb *dev = netdev_priv(netdev);
919 struct can_bittiming *bt = &dev->can.bittiming;
922 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
923 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
924 (((bt->phase_seg2 - 1) & 0x7) << 4);
925 if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
928 netdev_info(netdev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
930 dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
931 dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
933 return ems_usb_command_msg(dev, &dev->active_params);
936 static void init_params_sja1000(struct ems_cpc_msg *msg)
938 struct cpc_sja1000_params *sja1000 =
939 &msg->msg.can_params.cc_params.sja1000;
941 msg->type = CPC_CMD_TYPE_CAN_PARAMS;
942 msg->length = sizeof(struct cpc_can_params);
945 msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
947 /* Acceptance filter open */
948 sja1000->acc_code0 = 0x00;
949 sja1000->acc_code1 = 0x00;
950 sja1000->acc_code2 = 0x00;
951 sja1000->acc_code3 = 0x00;
953 /* Acceptance filter open */
954 sja1000->acc_mask0 = 0xFF;
955 sja1000->acc_mask1 = 0xFF;
956 sja1000->acc_mask2 = 0xFF;
957 sja1000->acc_mask3 = 0xFF;
962 sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
963 sja1000->mode = SJA1000_MOD_RM;
967 * probe function for new CPC-USB devices
969 static int ems_usb_probe(struct usb_interface *intf,
970 const struct usb_device_id *id)
972 struct net_device *netdev;
974 int i, err = -ENOMEM;
976 netdev = alloc_candev(sizeof(struct ems_usb), MAX_TX_URBS);
978 dev_err(&intf->dev, "ems_usb: Couldn't alloc candev\n");
982 dev = netdev_priv(netdev);
984 dev->udev = interface_to_usbdev(intf);
985 dev->netdev = netdev;
987 dev->can.state = CAN_STATE_STOPPED;
988 dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
989 dev->can.bittiming_const = &ems_usb_bittiming_const;
990 dev->can.do_set_bittiming = ems_usb_set_bittiming;
991 dev->can.do_set_mode = ems_usb_set_mode;
992 dev->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
994 netdev->netdev_ops = &ems_usb_netdev_ops;
996 netdev->flags |= IFF_ECHO; /* we support local echo */
998 init_usb_anchor(&dev->rx_submitted);
1000 init_usb_anchor(&dev->tx_submitted);
1001 atomic_set(&dev->active_tx_urbs, 0);
1003 for (i = 0; i < MAX_TX_URBS; i++)
1004 dev->tx_contexts[i].echo_index = MAX_TX_URBS;
1006 dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
1007 if (!dev->intr_urb) {
1008 dev_err(&intf->dev, "Couldn't alloc intr URB\n");
1009 goto cleanup_candev;
1012 dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
1013 if (!dev->intr_in_buffer)
1014 goto cleanup_intr_urb;
1016 dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
1017 sizeof(struct ems_cpc_msg), GFP_KERNEL);
1018 if (!dev->tx_msg_buffer)
1019 goto cleanup_intr_in_buffer;
1021 usb_set_intfdata(intf, dev);
1023 SET_NETDEV_DEV(netdev, &intf->dev);
1025 init_params_sja1000(&dev->active_params);
1027 err = ems_usb_command_msg(dev, &dev->active_params);
1029 netdev_err(netdev, "couldn't initialize controller: %d\n", err);
1030 goto cleanup_tx_msg_buffer;
1033 err = register_candev(netdev);
1035 netdev_err(netdev, "couldn't register CAN device: %d\n", err);
1036 goto cleanup_tx_msg_buffer;
1041 cleanup_tx_msg_buffer:
1042 kfree(dev->tx_msg_buffer);
1044 cleanup_intr_in_buffer:
1045 kfree(dev->intr_in_buffer);
1048 usb_free_urb(dev->intr_urb);
1051 free_candev(netdev);
1057 * called by the usb core when the device is removed from the system
1059 static void ems_usb_disconnect(struct usb_interface *intf)
1061 struct ems_usb *dev = usb_get_intfdata(intf);
1063 usb_set_intfdata(intf, NULL);
1066 unregister_netdev(dev->netdev);
1067 free_candev(dev->netdev);
1069 unlink_all_urbs(dev);
1071 usb_free_urb(dev->intr_urb);
1073 kfree(dev->intr_in_buffer);
1077 /* usb specific object needed to register this driver with the usb subsystem */
1078 static struct usb_driver ems_usb_driver = {
1080 .probe = ems_usb_probe,
1081 .disconnect = ems_usb_disconnect,
1082 .id_table = ems_usb_table,
1085 module_usb_driver(ems_usb_driver);