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/init.h>
20 #include <linux/signal.h>
21 #include <linux/slab.h>
22 #include <linux/module.h>
23 #include <linux/netdevice.h>
24 #include <linux/usb.h>
26 #include <linux/can.h>
27 #include <linux/can/dev.h>
28 #include <linux/can/error.h>
30 MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
31 MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
32 MODULE_LICENSE("GPL v2");
34 /* Control-Values for CPC_Control() Command Subject Selection */
35 #define CONTR_CAN_MESSAGE 0x04
36 #define CONTR_CAN_STATE 0x0C
37 #define CONTR_BUS_ERROR 0x1C
39 /* Control Command Actions */
40 #define CONTR_CONT_OFF 0
41 #define CONTR_CONT_ON 1
44 /* Messages from CPC to PC */
45 #define CPC_MSG_TYPE_CAN_FRAME 1 /* CAN data frame */
46 #define CPC_MSG_TYPE_RTR_FRAME 8 /* CAN remote frame */
47 #define CPC_MSG_TYPE_CAN_PARAMS 12 /* Actual CAN parameters */
48 #define CPC_MSG_TYPE_CAN_STATE 14 /* CAN state message */
49 #define CPC_MSG_TYPE_EXT_CAN_FRAME 16 /* Extended CAN data frame */
50 #define CPC_MSG_TYPE_EXT_RTR_FRAME 17 /* Extended remote frame */
51 #define CPC_MSG_TYPE_CONTROL 19 /* change interface behavior */
52 #define CPC_MSG_TYPE_CONFIRM 20 /* command processed confirmation */
53 #define CPC_MSG_TYPE_OVERRUN 21 /* overrun events */
54 #define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */
55 #define CPC_MSG_TYPE_ERR_COUNTER 25 /* RX/TX error counter */
57 /* Messages from the PC to the CPC interface */
58 #define CPC_CMD_TYPE_CAN_FRAME 1 /* CAN data frame */
59 #define CPC_CMD_TYPE_CONTROL 3 /* control of interface behavior */
60 #define CPC_CMD_TYPE_CAN_PARAMS 6 /* set CAN parameters */
61 #define CPC_CMD_TYPE_RTR_FRAME 13 /* CAN remote frame */
62 #define CPC_CMD_TYPE_CAN_STATE 14 /* CAN state message */
63 #define CPC_CMD_TYPE_EXT_CAN_FRAME 15 /* Extended CAN data frame */
64 #define CPC_CMD_TYPE_EXT_RTR_FRAME 16 /* Extended CAN remote frame */
65 #define CPC_CMD_TYPE_CAN_EXIT 200 /* exit the CAN */
67 #define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */
68 #define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8 /* clear CPC_MSG queue */
69 #define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */
71 #define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */
73 #define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */
76 #define CPC_OVR_EVENT_CAN 0x01
77 #define CPC_OVR_EVENT_CANSTATE 0x02
78 #define CPC_OVR_EVENT_BUSERROR 0x04
81 * If the CAN controller lost a message we indicate it with the highest bit
82 * set in the count field.
84 #define CPC_OVR_HW 0x80
86 /* Size of the "struct ems_cpc_msg" without the union */
87 #define CPC_MSG_HEADER_LEN 11
88 #define CPC_CAN_MSG_MIN_SIZE 5
90 /* Define these values to match your devices */
91 #define USB_CPCUSB_VENDOR_ID 0x12D6
93 #define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444
95 /* Mode register NXP LPC2119/SJA1000 CAN Controller */
96 #define SJA1000_MOD_NORMAL 0x00
97 #define SJA1000_MOD_RM 0x01
99 /* ECC register NXP LPC2119/SJA1000 CAN Controller */
100 #define SJA1000_ECC_SEG 0x1F
101 #define SJA1000_ECC_DIR 0x20
102 #define SJA1000_ECC_ERR 0x06
103 #define SJA1000_ECC_BIT 0x00
104 #define SJA1000_ECC_FORM 0x40
105 #define SJA1000_ECC_STUFF 0x80
106 #define SJA1000_ECC_MASK 0xc0
108 /* Status register content */
109 #define SJA1000_SR_BS 0x80
110 #define SJA1000_SR_ES 0x40
112 #define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA
115 * The device actually uses a 16MHz clock to generate the CAN clock
116 * but it expects SJA1000 bit settings based on 8MHz (is internally
119 #define EMS_USB_ARM7_CLOCK 8000000
122 * CAN-Message representation in a CPC_MSG. Message object type is
123 * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or
124 * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME.
132 /* Representation of the CAN parameters for the SJA1000 controller */
133 struct cpc_sja1000_params
{
148 /* CAN params message representation */
149 struct cpc_can_params
{
152 /* Will support M16C CAN controller in the future */
154 struct cpc_sja1000_params sja1000
;
158 /* Structure for confirmed message handling */
160 u8 error
; /* error code */
163 /* Structure for overrun conditions */
169 /* SJA1000 CAN errors (compatible to NXP LPC2119) */
170 struct cpc_sja1000_can_error
{
176 /* structure for CAN error conditions */
177 struct cpc_can_error
{
183 /* Other controllers may also provide error code capture regs */
185 struct cpc_sja1000_can_error sja1000
;
191 * Structure containing RX/TX error counter. This structure is used to request
192 * the values of the CAN controllers TX and RX error counter.
194 struct cpc_can_err_counter
{
199 /* Main message type used between library and application */
200 struct __packed ems_cpc_msg
{
201 u8 type
; /* type of message */
202 u8 length
; /* length of data within union 'msg' */
203 u8 msgid
; /* confirmation handle */
204 u32 ts_sec
; /* timestamp in seconds */
205 u32 ts_nsec
; /* timestamp in nano seconds */
209 struct cpc_can_msg can_msg
;
210 struct cpc_can_params can_params
;
211 struct cpc_confirm confirmation
;
212 struct cpc_overrun overrun
;
213 struct cpc_can_error error
;
214 struct cpc_can_err_counter err_counter
;
220 * Table of devices that work with this driver
221 * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet.
223 static struct usb_device_id ems_usb_table
[] = {
224 {USB_DEVICE(USB_CPCUSB_VENDOR_ID
, USB_CPCUSB_ARM7_PRODUCT_ID
)},
225 {} /* Terminating entry */
228 MODULE_DEVICE_TABLE(usb
, ems_usb_table
);
230 #define RX_BUFFER_SIZE 64
231 #define CPC_HEADER_SIZE 4
232 #define INTR_IN_BUFFER_SIZE 4
234 #define MAX_RX_URBS 10
235 #define MAX_TX_URBS 10
239 struct ems_tx_urb_context
{
247 struct can_priv can
; /* must be the first member */
249 struct sk_buff
*echo_skb
[MAX_TX_URBS
];
251 struct usb_device
*udev
;
252 struct net_device
*netdev
;
254 atomic_t active_tx_urbs
;
255 struct usb_anchor tx_submitted
;
256 struct ems_tx_urb_context tx_contexts
[MAX_TX_URBS
];
258 struct usb_anchor rx_submitted
;
260 struct urb
*intr_urb
;
265 unsigned int free_slots
; /* remember number of available slots */
267 struct ems_cpc_msg active_params
; /* active controller parameters */
270 static void ems_usb_read_interrupt_callback(struct urb
*urb
)
272 struct ems_usb
*dev
= urb
->context
;
273 struct net_device
*netdev
= dev
->netdev
;
276 if (!netif_device_present(netdev
))
279 switch (urb
->status
) {
281 dev
->free_slots
= dev
->intr_in_buffer
[1];
284 case -ECONNRESET
: /* unlink */
290 netdev_info(netdev
, "Rx interrupt aborted %d\n", urb
->status
);
294 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
297 netif_device_detach(netdev
);
299 netdev_err(netdev
, "failed resubmitting intr urb: %d\n", err
);
302 static void ems_usb_rx_can_msg(struct ems_usb
*dev
, struct ems_cpc_msg
*msg
)
304 struct can_frame
*cf
;
307 struct net_device_stats
*stats
= &dev
->netdev
->stats
;
309 skb
= alloc_can_skb(dev
->netdev
, &cf
);
313 cf
->can_id
= le32_to_cpu(msg
->msg
.can_msg
.id
);
314 cf
->can_dlc
= get_can_dlc(msg
->msg
.can_msg
.length
& 0xF);
316 if (msg
->type
== CPC_MSG_TYPE_EXT_CAN_FRAME
||
317 msg
->type
== CPC_MSG_TYPE_EXT_RTR_FRAME
)
318 cf
->can_id
|= CAN_EFF_FLAG
;
320 if (msg
->type
== CPC_MSG_TYPE_RTR_FRAME
||
321 msg
->type
== CPC_MSG_TYPE_EXT_RTR_FRAME
) {
322 cf
->can_id
|= CAN_RTR_FLAG
;
324 for (i
= 0; i
< cf
->can_dlc
; i
++)
325 cf
->data
[i
] = msg
->msg
.can_msg
.msg
[i
];
331 stats
->rx_bytes
+= cf
->can_dlc
;
334 static void ems_usb_rx_err(struct ems_usb
*dev
, struct ems_cpc_msg
*msg
)
336 struct can_frame
*cf
;
338 struct net_device_stats
*stats
= &dev
->netdev
->stats
;
340 skb
= alloc_can_err_skb(dev
->netdev
, &cf
);
344 if (msg
->type
== CPC_MSG_TYPE_CAN_STATE
) {
345 u8 state
= msg
->msg
.can_state
;
347 if (state
& SJA1000_SR_BS
) {
348 dev
->can
.state
= CAN_STATE_BUS_OFF
;
349 cf
->can_id
|= CAN_ERR_BUSOFF
;
351 can_bus_off(dev
->netdev
);
352 } else if (state
& SJA1000_SR_ES
) {
353 dev
->can
.state
= CAN_STATE_ERROR_WARNING
;
354 dev
->can
.can_stats
.error_warning
++;
356 dev
->can
.state
= CAN_STATE_ERROR_ACTIVE
;
357 dev
->can
.can_stats
.error_passive
++;
359 } else if (msg
->type
== CPC_MSG_TYPE_CAN_FRAME_ERROR
) {
360 u8 ecc
= msg
->msg
.error
.cc
.regs
.sja1000
.ecc
;
361 u8 txerr
= msg
->msg
.error
.cc
.regs
.sja1000
.txerr
;
362 u8 rxerr
= msg
->msg
.error
.cc
.regs
.sja1000
.rxerr
;
364 /* bus error interrupt */
365 dev
->can
.can_stats
.bus_error
++;
368 cf
->can_id
|= CAN_ERR_PROT
| CAN_ERR_BUSERROR
;
370 switch (ecc
& SJA1000_ECC_MASK
) {
371 case SJA1000_ECC_BIT
:
372 cf
->data
[2] |= CAN_ERR_PROT_BIT
;
374 case SJA1000_ECC_FORM
:
375 cf
->data
[2] |= CAN_ERR_PROT_FORM
;
377 case SJA1000_ECC_STUFF
:
378 cf
->data
[2] |= CAN_ERR_PROT_STUFF
;
381 cf
->data
[2] |= CAN_ERR_PROT_UNSPEC
;
382 cf
->data
[3] = ecc
& SJA1000_ECC_SEG
;
386 /* Error occurred during transmission? */
387 if ((ecc
& SJA1000_ECC_DIR
) == 0)
388 cf
->data
[2] |= CAN_ERR_PROT_TX
;
390 if (dev
->can
.state
== CAN_STATE_ERROR_WARNING
||
391 dev
->can
.state
== CAN_STATE_ERROR_PASSIVE
) {
392 cf
->data
[1] = (txerr
> rxerr
) ?
393 CAN_ERR_CRTL_TX_PASSIVE
: CAN_ERR_CRTL_RX_PASSIVE
;
395 } else if (msg
->type
== CPC_MSG_TYPE_OVERRUN
) {
396 cf
->can_id
|= CAN_ERR_CRTL
;
397 cf
->data
[1] = CAN_ERR_CRTL_RX_OVERFLOW
;
399 stats
->rx_over_errors
++;
406 stats
->rx_bytes
+= cf
->can_dlc
;
410 * callback for bulk IN urb
412 static void ems_usb_read_bulk_callback(struct urb
*urb
)
414 struct ems_usb
*dev
= urb
->context
;
415 struct net_device
*netdev
;
418 netdev
= dev
->netdev
;
420 if (!netif_device_present(netdev
))
423 switch (urb
->status
) {
424 case 0: /* success */
431 netdev_info(netdev
, "Rx URB aborted (%d)\n", urb
->status
);
435 if (urb
->actual_length
> CPC_HEADER_SIZE
) {
436 struct ems_cpc_msg
*msg
;
437 u8
*ibuf
= urb
->transfer_buffer
;
438 u8 msg_count
, again
, start
;
440 msg_count
= ibuf
[0] & ~0x80;
441 again
= ibuf
[0] & 0x80;
443 start
= CPC_HEADER_SIZE
;
446 msg
= (struct ems_cpc_msg
*)&ibuf
[start
];
449 case CPC_MSG_TYPE_CAN_STATE
:
450 /* Process CAN state changes */
451 ems_usb_rx_err(dev
, msg
);
454 case CPC_MSG_TYPE_CAN_FRAME
:
455 case CPC_MSG_TYPE_EXT_CAN_FRAME
:
456 case CPC_MSG_TYPE_RTR_FRAME
:
457 case CPC_MSG_TYPE_EXT_RTR_FRAME
:
458 ems_usb_rx_can_msg(dev
, msg
);
461 case CPC_MSG_TYPE_CAN_FRAME_ERROR
:
462 /* Process errorframe */
463 ems_usb_rx_err(dev
, msg
);
466 case CPC_MSG_TYPE_OVERRUN
:
467 /* Message lost while receiving */
468 ems_usb_rx_err(dev
, msg
);
472 start
+= CPC_MSG_HEADER_LEN
+ msg
->length
;
475 if (start
> urb
->transfer_buffer_length
) {
476 netdev_err(netdev
, "format error\n");
483 usb_fill_bulk_urb(urb
, dev
->udev
, usb_rcvbulkpipe(dev
->udev
, 2),
484 urb
->transfer_buffer
, RX_BUFFER_SIZE
,
485 ems_usb_read_bulk_callback
, dev
);
487 retval
= usb_submit_urb(urb
, GFP_ATOMIC
);
489 if (retval
== -ENODEV
)
490 netif_device_detach(netdev
);
493 "failed resubmitting read bulk urb: %d\n", retval
);
497 * callback for bulk IN urb
499 static void ems_usb_write_bulk_callback(struct urb
*urb
)
501 struct ems_tx_urb_context
*context
= urb
->context
;
503 struct net_device
*netdev
;
508 netdev
= dev
->netdev
;
510 /* free up our allocated buffer */
511 usb_free_coherent(urb
->dev
, urb
->transfer_buffer_length
,
512 urb
->transfer_buffer
, urb
->transfer_dma
);
514 atomic_dec(&dev
->active_tx_urbs
);
516 if (!netif_device_present(netdev
))
520 netdev_info(netdev
, "Tx URB aborted (%d)\n", urb
->status
);
522 netdev
->trans_start
= jiffies
;
524 /* transmission complete interrupt */
525 netdev
->stats
.tx_packets
++;
526 netdev
->stats
.tx_bytes
+= context
->dlc
;
528 can_get_echo_skb(netdev
, context
->echo_index
);
530 /* Release context */
531 context
->echo_index
= MAX_TX_URBS
;
533 if (netif_queue_stopped(netdev
))
534 netif_wake_queue(netdev
);
538 * Send the given CPC command synchronously
540 static int ems_usb_command_msg(struct ems_usb
*dev
, struct ems_cpc_msg
*msg
)
545 memcpy(&dev
->tx_msg_buffer
[CPC_HEADER_SIZE
], msg
,
546 msg
->length
+ CPC_MSG_HEADER_LEN
);
549 memset(&dev
->tx_msg_buffer
[0], 0, CPC_HEADER_SIZE
);
551 return usb_bulk_msg(dev
->udev
, usb_sndbulkpipe(dev
->udev
, 2),
552 &dev
->tx_msg_buffer
[0],
553 msg
->length
+ CPC_MSG_HEADER_LEN
+ CPC_HEADER_SIZE
,
554 &actual_length
, 1000);
558 * Change CAN controllers' mode register
560 static int ems_usb_write_mode(struct ems_usb
*dev
, u8 mode
)
562 dev
->active_params
.msg
.can_params
.cc_params
.sja1000
.mode
= mode
;
564 return ems_usb_command_msg(dev
, &dev
->active_params
);
568 * Send a CPC_Control command to change behaviour when interface receives a CAN
569 * message, bus error or CAN state changed notifications.
571 static int ems_usb_control_cmd(struct ems_usb
*dev
, u8 val
)
573 struct ems_cpc_msg cmd
;
575 cmd
.type
= CPC_CMD_TYPE_CONTROL
;
576 cmd
.length
= CPC_MSG_HEADER_LEN
+ 1;
580 cmd
.msg
.generic
[0] = val
;
582 return ems_usb_command_msg(dev
, &cmd
);
588 static int ems_usb_start(struct ems_usb
*dev
)
590 struct net_device
*netdev
= dev
->netdev
;
593 dev
->intr_in_buffer
[0] = 0;
594 dev
->free_slots
= 15; /* initial size */
596 for (i
= 0; i
< MAX_RX_URBS
; i
++) {
597 struct urb
*urb
= NULL
;
600 /* create a URB, and a buffer for it */
601 urb
= usb_alloc_urb(0, GFP_KERNEL
);
603 netdev_err(netdev
, "No memory left for URBs\n");
608 buf
= usb_alloc_coherent(dev
->udev
, RX_BUFFER_SIZE
, GFP_KERNEL
,
611 netdev_err(netdev
, "No memory left for USB buffer\n");
617 usb_fill_bulk_urb(urb
, dev
->udev
, usb_rcvbulkpipe(dev
->udev
, 2),
619 ems_usb_read_bulk_callback
, dev
);
620 urb
->transfer_flags
|= URB_NO_TRANSFER_DMA_MAP
;
621 usb_anchor_urb(urb
, &dev
->rx_submitted
);
623 err
= usb_submit_urb(urb
, GFP_KERNEL
);
625 usb_unanchor_urb(urb
);
626 usb_free_coherent(dev
->udev
, RX_BUFFER_SIZE
, buf
,
631 /* Drop reference, USB core will take care of freeing it */
635 /* Did we submit any URBs */
637 netdev_warn(netdev
, "couldn't setup read URBs\n");
641 /* Warn if we've couldn't transmit all the URBs */
643 netdev_warn(netdev
, "rx performance may be slow\n");
645 /* Setup and start interrupt URB */
646 usb_fill_int_urb(dev
->intr_urb
, dev
->udev
,
647 usb_rcvintpipe(dev
->udev
, 1),
650 ems_usb_read_interrupt_callback
, dev
, 1);
652 err
= usb_submit_urb(dev
->intr_urb
, GFP_KERNEL
);
654 netdev_warn(netdev
, "intr URB submit failed: %d\n", err
);
659 /* CPC-USB will transfer received message to host */
660 err
= ems_usb_control_cmd(dev
, CONTR_CAN_MESSAGE
| CONTR_CONT_ON
);
664 /* CPC-USB will transfer CAN state changes to host */
665 err
= ems_usb_control_cmd(dev
, CONTR_CAN_STATE
| CONTR_CONT_ON
);
669 /* CPC-USB will transfer bus errors to host */
670 err
= ems_usb_control_cmd(dev
, CONTR_BUS_ERROR
| CONTR_CONT_ON
);
674 err
= ems_usb_write_mode(dev
, SJA1000_MOD_NORMAL
);
678 dev
->can
.state
= CAN_STATE_ERROR_ACTIVE
;
683 netdev_warn(netdev
, "couldn't submit control: %d\n", err
);
688 static void unlink_all_urbs(struct ems_usb
*dev
)
692 usb_unlink_urb(dev
->intr_urb
);
694 usb_kill_anchored_urbs(&dev
->rx_submitted
);
696 usb_kill_anchored_urbs(&dev
->tx_submitted
);
697 atomic_set(&dev
->active_tx_urbs
, 0);
699 for (i
= 0; i
< MAX_TX_URBS
; i
++)
700 dev
->tx_contexts
[i
].echo_index
= MAX_TX_URBS
;
703 static int ems_usb_open(struct net_device
*netdev
)
705 struct ems_usb
*dev
= netdev_priv(netdev
);
708 err
= ems_usb_write_mode(dev
, SJA1000_MOD_RM
);
713 err
= open_candev(netdev
);
717 /* finally start device */
718 err
= ems_usb_start(dev
);
721 netif_device_detach(dev
->netdev
);
723 netdev_warn(netdev
, "couldn't start device: %d\n", err
);
725 close_candev(netdev
);
731 netif_start_queue(netdev
);
736 static netdev_tx_t
ems_usb_start_xmit(struct sk_buff
*skb
, struct net_device
*netdev
)
738 struct ems_usb
*dev
= netdev_priv(netdev
);
739 struct ems_tx_urb_context
*context
= NULL
;
740 struct net_device_stats
*stats
= &netdev
->stats
;
741 struct can_frame
*cf
= (struct can_frame
*)skb
->data
;
742 struct ems_cpc_msg
*msg
;
746 size_t size
= CPC_HEADER_SIZE
+ CPC_MSG_HEADER_LEN
747 + sizeof(struct cpc_can_msg
);
749 if (can_dropped_invalid_skb(netdev
, skb
))
752 /* create a URB, and a buffer for it, and copy the data to the URB */
753 urb
= usb_alloc_urb(0, GFP_ATOMIC
);
755 netdev_err(netdev
, "No memory left for URBs\n");
759 buf
= usb_alloc_coherent(dev
->udev
, size
, GFP_ATOMIC
, &urb
->transfer_dma
);
761 netdev_err(netdev
, "No memory left for USB buffer\n");
766 msg
= (struct ems_cpc_msg
*)&buf
[CPC_HEADER_SIZE
];
768 msg
->msg
.can_msg
.id
= cf
->can_id
& CAN_ERR_MASK
;
769 msg
->msg
.can_msg
.length
= cf
->can_dlc
;
771 if (cf
->can_id
& CAN_RTR_FLAG
) {
772 msg
->type
= cf
->can_id
& CAN_EFF_FLAG
?
773 CPC_CMD_TYPE_EXT_RTR_FRAME
: CPC_CMD_TYPE_RTR_FRAME
;
775 msg
->length
= CPC_CAN_MSG_MIN_SIZE
;
777 msg
->type
= cf
->can_id
& CAN_EFF_FLAG
?
778 CPC_CMD_TYPE_EXT_CAN_FRAME
: CPC_CMD_TYPE_CAN_FRAME
;
780 for (i
= 0; i
< cf
->can_dlc
; i
++)
781 msg
->msg
.can_msg
.msg
[i
] = cf
->data
[i
];
783 msg
->length
= CPC_CAN_MSG_MIN_SIZE
+ cf
->can_dlc
;
786 /* Respect byte order */
787 msg
->msg
.can_msg
.id
= cpu_to_le32(msg
->msg
.can_msg
.id
);
789 for (i
= 0; i
< MAX_TX_URBS
; i
++) {
790 if (dev
->tx_contexts
[i
].echo_index
== MAX_TX_URBS
) {
791 context
= &dev
->tx_contexts
[i
];
797 * May never happen! When this happens we'd more URBs in flight as
798 * allowed (MAX_TX_URBS).
801 usb_unanchor_urb(urb
);
802 usb_free_coherent(dev
->udev
, size
, buf
, urb
->transfer_dma
);
804 netdev_warn(netdev
, "couldn't find free context\n");
806 return NETDEV_TX_BUSY
;
810 context
->echo_index
= i
;
811 context
->dlc
= cf
->can_dlc
;
813 usb_fill_bulk_urb(urb
, dev
->udev
, usb_sndbulkpipe(dev
->udev
, 2), buf
,
814 size
, ems_usb_write_bulk_callback
, context
);
815 urb
->transfer_flags
|= URB_NO_TRANSFER_DMA_MAP
;
816 usb_anchor_urb(urb
, &dev
->tx_submitted
);
818 can_put_echo_skb(skb
, netdev
, context
->echo_index
);
820 atomic_inc(&dev
->active_tx_urbs
);
822 err
= usb_submit_urb(urb
, GFP_ATOMIC
);
824 can_free_echo_skb(netdev
, context
->echo_index
);
826 usb_unanchor_urb(urb
);
827 usb_free_coherent(dev
->udev
, size
, buf
, urb
->transfer_dma
);
830 atomic_dec(&dev
->active_tx_urbs
);
832 if (err
== -ENODEV
) {
833 netif_device_detach(netdev
);
835 netdev_warn(netdev
, "failed tx_urb %d\n", err
);
840 netdev
->trans_start
= jiffies
;
842 /* Slow down tx path */
843 if (atomic_read(&dev
->active_tx_urbs
) >= MAX_TX_URBS
||
844 dev
->free_slots
< 5) {
845 netif_stop_queue(netdev
);
850 * Release our reference to this URB, the USB core will eventually free
864 static int ems_usb_close(struct net_device
*netdev
)
866 struct ems_usb
*dev
= netdev_priv(netdev
);
869 unlink_all_urbs(dev
);
871 netif_stop_queue(netdev
);
873 /* Set CAN controller to reset mode */
874 if (ems_usb_write_mode(dev
, SJA1000_MOD_RM
))
875 netdev_warn(netdev
, "couldn't stop device");
877 close_candev(netdev
);
882 static const struct net_device_ops ems_usb_netdev_ops
= {
883 .ndo_open
= ems_usb_open
,
884 .ndo_stop
= ems_usb_close
,
885 .ndo_start_xmit
= ems_usb_start_xmit
,
888 static const struct can_bittiming_const ems_usb_bittiming_const
= {
900 static int ems_usb_set_mode(struct net_device
*netdev
, enum can_mode mode
)
902 struct ems_usb
*dev
= netdev_priv(netdev
);
906 if (ems_usb_write_mode(dev
, SJA1000_MOD_NORMAL
))
907 netdev_warn(netdev
, "couldn't start device");
909 if (netif_queue_stopped(netdev
))
910 netif_wake_queue(netdev
);
920 static int ems_usb_set_bittiming(struct net_device
*netdev
)
922 struct ems_usb
*dev
= netdev_priv(netdev
);
923 struct can_bittiming
*bt
= &dev
->can
.bittiming
;
926 btr0
= ((bt
->brp
- 1) & 0x3f) | (((bt
->sjw
- 1) & 0x3) << 6);
927 btr1
= ((bt
->prop_seg
+ bt
->phase_seg1
- 1) & 0xf) |
928 (((bt
->phase_seg2
- 1) & 0x7) << 4);
929 if (dev
->can
.ctrlmode
& CAN_CTRLMODE_3_SAMPLES
)
932 netdev_info(netdev
, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0
, btr1
);
934 dev
->active_params
.msg
.can_params
.cc_params
.sja1000
.btr0
= btr0
;
935 dev
->active_params
.msg
.can_params
.cc_params
.sja1000
.btr1
= btr1
;
937 return ems_usb_command_msg(dev
, &dev
->active_params
);
940 static void init_params_sja1000(struct ems_cpc_msg
*msg
)
942 struct cpc_sja1000_params
*sja1000
=
943 &msg
->msg
.can_params
.cc_params
.sja1000
;
945 msg
->type
= CPC_CMD_TYPE_CAN_PARAMS
;
946 msg
->length
= sizeof(struct cpc_can_params
);
949 msg
->msg
.can_params
.cc_type
= CPC_CC_TYPE_SJA1000
;
951 /* Acceptance filter open */
952 sja1000
->acc_code0
= 0x00;
953 sja1000
->acc_code1
= 0x00;
954 sja1000
->acc_code2
= 0x00;
955 sja1000
->acc_code3
= 0x00;
957 /* Acceptance filter open */
958 sja1000
->acc_mask0
= 0xFF;
959 sja1000
->acc_mask1
= 0xFF;
960 sja1000
->acc_mask2
= 0xFF;
961 sja1000
->acc_mask3
= 0xFF;
966 sja1000
->outp_contr
= SJA1000_DEFAULT_OUTPUT_CONTROL
;
967 sja1000
->mode
= SJA1000_MOD_RM
;
971 * probe function for new CPC-USB devices
973 static int ems_usb_probe(struct usb_interface
*intf
,
974 const struct usb_device_id
*id
)
976 struct net_device
*netdev
;
978 int i
, err
= -ENOMEM
;
980 netdev
= alloc_candev(sizeof(struct ems_usb
), MAX_TX_URBS
);
982 dev_err(&intf
->dev
, "ems_usb: Couldn't alloc candev\n");
986 dev
= netdev_priv(netdev
);
988 dev
->udev
= interface_to_usbdev(intf
);
989 dev
->netdev
= netdev
;
991 dev
->can
.state
= CAN_STATE_STOPPED
;
992 dev
->can
.clock
.freq
= EMS_USB_ARM7_CLOCK
;
993 dev
->can
.bittiming_const
= &ems_usb_bittiming_const
;
994 dev
->can
.do_set_bittiming
= ems_usb_set_bittiming
;
995 dev
->can
.do_set_mode
= ems_usb_set_mode
;
996 dev
->can
.ctrlmode_supported
= CAN_CTRLMODE_3_SAMPLES
;
998 netdev
->netdev_ops
= &ems_usb_netdev_ops
;
1000 netdev
->flags
|= IFF_ECHO
; /* we support local echo */
1002 init_usb_anchor(&dev
->rx_submitted
);
1004 init_usb_anchor(&dev
->tx_submitted
);
1005 atomic_set(&dev
->active_tx_urbs
, 0);
1007 for (i
= 0; i
< MAX_TX_URBS
; i
++)
1008 dev
->tx_contexts
[i
].echo_index
= MAX_TX_URBS
;
1010 dev
->intr_urb
= usb_alloc_urb(0, GFP_KERNEL
);
1011 if (!dev
->intr_urb
) {
1012 dev_err(&intf
->dev
, "Couldn't alloc intr URB\n");
1013 goto cleanup_candev
;
1016 dev
->intr_in_buffer
= kzalloc(INTR_IN_BUFFER_SIZE
, GFP_KERNEL
);
1017 if (!dev
->intr_in_buffer
) {
1018 dev_err(&intf
->dev
, "Couldn't alloc Intr buffer\n");
1019 goto cleanup_intr_urb
;
1022 dev
->tx_msg_buffer
= kzalloc(CPC_HEADER_SIZE
+
1023 sizeof(struct ems_cpc_msg
), GFP_KERNEL
);
1024 if (!dev
->tx_msg_buffer
) {
1025 dev_err(&intf
->dev
, "Couldn't alloc Tx buffer\n");
1026 goto cleanup_intr_in_buffer
;
1029 usb_set_intfdata(intf
, dev
);
1031 SET_NETDEV_DEV(netdev
, &intf
->dev
);
1033 init_params_sja1000(&dev
->active_params
);
1035 err
= ems_usb_command_msg(dev
, &dev
->active_params
);
1037 netdev_err(netdev
, "couldn't initialize controller: %d\n", err
);
1038 goto cleanup_tx_msg_buffer
;
1041 err
= register_candev(netdev
);
1043 netdev_err(netdev
, "couldn't register CAN device: %d\n", err
);
1044 goto cleanup_tx_msg_buffer
;
1049 cleanup_tx_msg_buffer
:
1050 kfree(dev
->tx_msg_buffer
);
1052 cleanup_intr_in_buffer
:
1053 kfree(dev
->intr_in_buffer
);
1056 usb_free_urb(dev
->intr_urb
);
1059 free_candev(netdev
);
1065 * called by the usb core when the device is removed from the system
1067 static void ems_usb_disconnect(struct usb_interface
*intf
)
1069 struct ems_usb
*dev
= usb_get_intfdata(intf
);
1071 usb_set_intfdata(intf
, NULL
);
1074 unregister_netdev(dev
->netdev
);
1075 free_candev(dev
->netdev
);
1077 unlink_all_urbs(dev
);
1079 usb_free_urb(dev
->intr_urb
);
1081 kfree(dev
->intr_in_buffer
);
1085 /* usb specific object needed to register this driver with the usb subsystem */
1086 static struct usb_driver ems_usb_driver
= {
1088 .probe
= ems_usb_probe
,
1089 .disconnect
= ems_usb_disconnect
,
1090 .id_table
= ems_usb_table
,
1093 module_usb_driver(ems_usb_driver
);