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
);