2 * Janz MODULbus VMOD-ICAN3 CAN Interface Driver
4 * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
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 by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/interrupt.h>
15 #include <linux/delay.h>
16 #include <linux/platform_device.h>
18 #include <linux/netdevice.h>
19 #include <linux/can.h>
20 #include <linux/can/dev.h>
21 #include <linux/can/error.h>
23 #include <linux/mfd/janz.h>
26 /* the DPM has 64k of memory, organized into 256x 256 byte pages */
27 #define DPM_NUM_PAGES 256
28 #define DPM_PAGE_SIZE 256
29 #define DPM_PAGE_ADDR(p) ((p) * DPM_PAGE_SIZE)
31 /* JANZ ICAN3 "old-style" host interface queue page numbers */
32 #define QUEUE_OLD_CONTROL 0
33 #define QUEUE_OLD_RB0 1
34 #define QUEUE_OLD_RB1 2
35 #define QUEUE_OLD_WB0 3
36 #define QUEUE_OLD_WB1 4
38 /* Janz ICAN3 "old-style" host interface control registers */
39 #define MSYNC_PEER 0x00 /* ICAN only */
40 #define MSYNC_LOCL 0x01 /* host only */
41 #define TARGET_RUNNING 0x02
43 #define MSYNC_RB0 0x01
44 #define MSYNC_RB1 0x02
45 #define MSYNC_RBLW 0x04
46 #define MSYNC_RB_MASK (MSYNC_RB0 | MSYNC_RB1)
48 #define MSYNC_WB0 0x10
49 #define MSYNC_WB1 0x20
50 #define MSYNC_WBLW 0x40
51 #define MSYNC_WB_MASK (MSYNC_WB0 | MSYNC_WB1)
53 /* Janz ICAN3 "new-style" host interface queue page numbers */
54 #define QUEUE_TOHOST 5
55 #define QUEUE_FROMHOST_MID 6
56 #define QUEUE_FROMHOST_HIGH 7
57 #define QUEUE_FROMHOST_LOW 8
59 /* The first free page in the DPM is #9 */
60 #define DPM_FREE_START 9
62 /* Janz ICAN3 "new-style" and "fast" host interface descriptor flags */
63 #define DESC_VALID 0x80
64 #define DESC_WRAP 0x40
65 #define DESC_INTERRUPT 0x20
66 #define DESC_IVALID 0x10
67 #define DESC_LEN(len) (len)
69 /* Janz ICAN3 Firmware Messages */
70 #define MSG_CONNECTI 0x02
71 #define MSG_DISCONNECT 0x03
72 #define MSG_IDVERS 0x04
73 #define MSG_MSGLOST 0x05
74 #define MSG_NEWHOSTIF 0x08
75 #define MSG_INQUIRY 0x0a
76 #define MSG_SETAFILMASK 0x10
77 #define MSG_INITFDPMQUEUE 0x11
78 #define MSG_HWCONF 0x12
79 #define MSG_FMSGLOST 0x15
80 #define MSG_CEVTIND 0x37
81 #define MSG_CBTRREQ 0x41
82 #define MSG_COFFREQ 0x42
83 #define MSG_CONREQ 0x43
84 #define MSG_CCONFREQ 0x47
87 * Janz ICAN3 CAN Inquiry Message Types
89 * NOTE: there appears to be a firmware bug here. You must send
90 * NOTE: INQUIRY_STATUS and expect to receive an INQUIRY_EXTENDED
91 * NOTE: response. The controller never responds to a message with
92 * NOTE: the INQUIRY_EXTENDED subspec :(
94 #define INQUIRY_STATUS 0x00
95 #define INQUIRY_TERMINATION 0x01
96 #define INQUIRY_EXTENDED 0x04
98 /* Janz ICAN3 CAN Set Acceptance Filter Mask Message Types */
99 #define SETAFILMASK_REJECT 0x00
100 #define SETAFILMASK_FASTIF 0x02
102 /* Janz ICAN3 CAN Hardware Configuration Message Types */
103 #define HWCONF_TERMINATE_ON 0x01
104 #define HWCONF_TERMINATE_OFF 0x00
106 /* Janz ICAN3 CAN Event Indication Message Types */
107 #define CEVTIND_EI 0x01
108 #define CEVTIND_DOI 0x02
109 #define CEVTIND_LOST 0x04
110 #define CEVTIND_FULL 0x08
111 #define CEVTIND_BEI 0x10
113 #define CEVTIND_CHIP_SJA1000 0x02
115 #define ICAN3_BUSERR_QUOTA_MAX 255
117 /* Janz ICAN3 CAN Frame Conversion */
118 #define ICAN3_SNGL 0x02
119 #define ICAN3_ECHO 0x10
120 #define ICAN3_EFF_RTR 0x40
121 #define ICAN3_SFF_RTR 0x10
122 #define ICAN3_EFF 0x80
124 #define ICAN3_CAN_TYPE_MASK 0x0f
125 #define ICAN3_CAN_TYPE_SFF 0x00
126 #define ICAN3_CAN_TYPE_EFF 0x01
128 #define ICAN3_CAN_DLC_MASK 0x0f
131 * SJA1000 Status and Error Register Definitions
133 * Copied from drivers/net/can/sja1000/sja1000.h
136 /* status register content */
146 #define SR_CRIT (SR_BS|SR_ES)
153 #define ECC_FORM 0x40
154 #define ECC_STUFF 0x80
155 #define ECC_MASK 0xc0
157 /* Number of buffers for use in the "new-style" host interface */
158 #define ICAN3_NEW_BUFFERS 16
160 /* Number of buffers for use in the "fast" host interface */
161 #define ICAN3_TX_BUFFERS 512
162 #define ICAN3_RX_BUFFERS 1024
164 /* SJA1000 Clock Input */
165 #define ICAN3_CAN_CLOCK 8000000
168 #define DRV_NAME "janz-ican3"
170 /* DPM Control Registers -- starts at offset 0x100 in the MODULbus registers */
171 struct ican3_dpm_control
{
172 /* window address register */
177 * Read access: clear interrupt from microcontroller
178 * Write access: send interrupt to microcontroller
183 /* write-only: reset all hardware on the module */
187 /* write-only: generate an interrupt to the TPU */
193 /* must be the first member */
196 /* CAN network device */
197 struct net_device
*ndev
;
198 struct napi_struct napi
;
200 /* Device for printing */
206 /* base address of registers and IRQ */
207 struct janz_cmodio_onboard_regs __iomem
*ctrl
;
208 struct ican3_dpm_control __iomem
*dpmctrl
;
212 /* CAN bus termination status */
213 struct completion termination_comp
;
214 bool termination_enabled
;
216 /* CAN bus error status registers */
217 struct completion buserror_comp
;
218 struct can_berr_counter bec
;
220 /* old and new style host interface */
223 /* queue for echo packets */
224 struct sk_buff_head echoq
;
227 * Any function which changes the current DPM page must hold this
228 * lock while it is performing data accesses. This ensures that the
229 * function will not be preempted and end up reading data from a
230 * different DPM page than it expects.
234 /* new host interface */
239 /* fast host interface */
240 unsigned int fastrx_start
;
241 unsigned int fastrx_num
;
242 unsigned int fasttx_start
;
243 unsigned int fasttx_num
;
245 /* first free DPM page */
246 unsigned int free_page
;
256 struct ican3_new_desc
{
261 struct ican3_fast_desc
{
267 /* write to the window basic address register */
268 static inline void ican3_set_page(struct ican3_dev
*mod
, unsigned int page
)
270 BUG_ON(page
>= DPM_NUM_PAGES
);
271 iowrite8(page
, &mod
->dpmctrl
->window_address
);
275 * ICAN3 "old-style" host interface
279 * Receive a message from the ICAN3 "old-style" firmware interface
281 * LOCKING: must hold mod->lock
283 * returns 0 on success, -ENOMEM when no message exists
285 static int ican3_old_recv_msg(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
287 unsigned int mbox
, mbox_page
;
290 /* get the MSYNC registers */
291 ican3_set_page(mod
, QUEUE_OLD_CONTROL
);
292 peer
= ioread8(mod
->dpm
+ MSYNC_PEER
);
293 locl
= ioread8(mod
->dpm
+ MSYNC_LOCL
);
296 if ((xord
& MSYNC_RB_MASK
) == 0x00) {
297 dev_dbg(mod
->dev
, "no mbox for reading\n");
301 /* find the first free mbox to read */
302 if ((xord
& MSYNC_RB_MASK
) == MSYNC_RB_MASK
)
303 mbox
= (xord
& MSYNC_RBLW
) ? MSYNC_RB0
: MSYNC_RB1
;
305 mbox
= (xord
& MSYNC_RB0
) ? MSYNC_RB0
: MSYNC_RB1
;
307 /* copy the message */
308 mbox_page
= (mbox
== MSYNC_RB0
) ? QUEUE_OLD_RB0
: QUEUE_OLD_RB1
;
309 ican3_set_page(mod
, mbox_page
);
310 memcpy_fromio(msg
, mod
->dpm
, sizeof(*msg
));
313 * notify the firmware that the read buffer is available
314 * for it to fill again
318 ican3_set_page(mod
, QUEUE_OLD_CONTROL
);
319 iowrite8(locl
, mod
->dpm
+ MSYNC_LOCL
);
324 * Send a message through the "old-style" firmware interface
326 * LOCKING: must hold mod->lock
328 * returns 0 on success, -ENOMEM when no free space exists
330 static int ican3_old_send_msg(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
332 unsigned int mbox
, mbox_page
;
335 /* get the MSYNC registers */
336 ican3_set_page(mod
, QUEUE_OLD_CONTROL
);
337 peer
= ioread8(mod
->dpm
+ MSYNC_PEER
);
338 locl
= ioread8(mod
->dpm
+ MSYNC_LOCL
);
341 if ((xord
& MSYNC_WB_MASK
) == MSYNC_WB_MASK
) {
342 dev_err(mod
->dev
, "no mbox for writing\n");
346 /* calculate a free mbox to use */
347 mbox
= (xord
& MSYNC_WB0
) ? MSYNC_WB1
: MSYNC_WB0
;
349 /* copy the message to the DPM */
350 mbox_page
= (mbox
== MSYNC_WB0
) ? QUEUE_OLD_WB0
: QUEUE_OLD_WB1
;
351 ican3_set_page(mod
, mbox_page
);
352 memcpy_toio(mod
->dpm
, msg
, sizeof(*msg
));
355 if (mbox
== MSYNC_WB1
)
358 ican3_set_page(mod
, QUEUE_OLD_CONTROL
);
359 iowrite8(locl
, mod
->dpm
+ MSYNC_LOCL
);
364 * ICAN3 "new-style" Host Interface Setup
367 static void ican3_init_new_host_interface(struct ican3_dev
*mod
)
369 struct ican3_new_desc desc
;
374 spin_lock_irqsave(&mod
->lock
, flags
);
376 /* setup the internal datastructures for RX */
380 /* tohost queue descriptors are in page 5 */
381 ican3_set_page(mod
, QUEUE_TOHOST
);
384 /* initialize the tohost (rx) queue descriptors: pages 9-24 */
385 for (i
= 0; i
< ICAN3_NEW_BUFFERS
; i
++) {
386 desc
.control
= DESC_INTERRUPT
| DESC_LEN(1); /* I L=1 */
387 desc
.pointer
= mod
->free_page
;
389 /* set wrap flag on last buffer */
390 if (i
== ICAN3_NEW_BUFFERS
- 1)
391 desc
.control
|= DESC_WRAP
;
393 memcpy_toio(dst
, &desc
, sizeof(desc
));
398 /* fromhost (tx) mid queue descriptors are in page 6 */
399 ican3_set_page(mod
, QUEUE_FROMHOST_MID
);
402 /* setup the internal datastructures for TX */
405 /* initialize the fromhost mid queue descriptors: pages 25-40 */
406 for (i
= 0; i
< ICAN3_NEW_BUFFERS
; i
++) {
407 desc
.control
= DESC_VALID
| DESC_LEN(1); /* V L=1 */
408 desc
.pointer
= mod
->free_page
;
410 /* set wrap flag on last buffer */
411 if (i
== ICAN3_NEW_BUFFERS
- 1)
412 desc
.control
|= DESC_WRAP
;
414 memcpy_toio(dst
, &desc
, sizeof(desc
));
419 /* fromhost hi queue descriptors are in page 7 */
420 ican3_set_page(mod
, QUEUE_FROMHOST_HIGH
);
423 /* initialize only a single buffer in the fromhost hi queue (unused) */
424 desc
.control
= DESC_VALID
| DESC_WRAP
| DESC_LEN(1); /* VW L=1 */
425 desc
.pointer
= mod
->free_page
;
426 memcpy_toio(dst
, &desc
, sizeof(desc
));
429 /* fromhost low queue descriptors are in page 8 */
430 ican3_set_page(mod
, QUEUE_FROMHOST_LOW
);
433 /* initialize only a single buffer in the fromhost low queue (unused) */
434 desc
.control
= DESC_VALID
| DESC_WRAP
| DESC_LEN(1); /* VW L=1 */
435 desc
.pointer
= mod
->free_page
;
436 memcpy_toio(dst
, &desc
, sizeof(desc
));
439 spin_unlock_irqrestore(&mod
->lock
, flags
);
443 * ICAN3 Fast Host Interface Setup
446 static void ican3_init_fast_host_interface(struct ican3_dev
*mod
)
448 struct ican3_fast_desc desc
;
454 spin_lock_irqsave(&mod
->lock
, flags
);
456 /* save the start recv page */
457 mod
->fastrx_start
= mod
->free_page
;
460 /* build a single fast tohost queue descriptor */
461 memset(&desc
, 0, sizeof(desc
));
465 /* build the tohost queue descriptor ring in memory */
467 for (i
= 0; i
< ICAN3_RX_BUFFERS
; i
++) {
469 /* set the wrap bit on the last buffer */
470 if (i
== ICAN3_RX_BUFFERS
- 1)
471 desc
.control
|= DESC_WRAP
;
473 /* switch to the correct page */
474 ican3_set_page(mod
, mod
->free_page
);
476 /* copy the descriptor to the DPM */
477 dst
= mod
->dpm
+ addr
;
478 memcpy_toio(dst
, &desc
, sizeof(desc
));
479 addr
+= sizeof(desc
);
481 /* move to the next page if necessary */
482 if (addr
>= DPM_PAGE_SIZE
) {
488 /* make sure we page-align the next queue */
492 /* save the start xmit page */
493 mod
->fasttx_start
= mod
->free_page
;
496 /* build a single fast fromhost queue descriptor */
497 memset(&desc
, 0, sizeof(desc
));
498 desc
.control
= DESC_VALID
;
501 /* build the fromhost queue descriptor ring in memory */
503 for (i
= 0; i
< ICAN3_TX_BUFFERS
; i
++) {
505 /* set the wrap bit on the last buffer */
506 if (i
== ICAN3_TX_BUFFERS
- 1)
507 desc
.control
|= DESC_WRAP
;
509 /* switch to the correct page */
510 ican3_set_page(mod
, mod
->free_page
);
512 /* copy the descriptor to the DPM */
513 dst
= mod
->dpm
+ addr
;
514 memcpy_toio(dst
, &desc
, sizeof(desc
));
515 addr
+= sizeof(desc
);
517 /* move to the next page if necessary */
518 if (addr
>= DPM_PAGE_SIZE
) {
524 spin_unlock_irqrestore(&mod
->lock
, flags
);
528 * ICAN3 "new-style" Host Interface Message Helpers
532 * LOCKING: must hold mod->lock
534 static int ican3_new_send_msg(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
536 struct ican3_new_desc desc
;
537 void __iomem
*desc_addr
= mod
->dpm
+ (mod
->tx_num
* sizeof(desc
));
539 /* switch to the fromhost mid queue, and read the buffer descriptor */
540 ican3_set_page(mod
, QUEUE_FROMHOST_MID
);
541 memcpy_fromio(&desc
, desc_addr
, sizeof(desc
));
543 if (!(desc
.control
& DESC_VALID
)) {
544 dev_dbg(mod
->dev
, "%s: no free buffers\n", __func__
);
548 /* switch to the data page, copy the data */
549 ican3_set_page(mod
, desc
.pointer
);
550 memcpy_toio(mod
->dpm
, msg
, sizeof(*msg
));
552 /* switch back to the descriptor, set the valid bit, write it back */
553 ican3_set_page(mod
, QUEUE_FROMHOST_MID
);
554 desc
.control
^= DESC_VALID
;
555 memcpy_toio(desc_addr
, &desc
, sizeof(desc
));
557 /* update the tx number */
558 mod
->tx_num
= (desc
.control
& DESC_WRAP
) ? 0 : (mod
->tx_num
+ 1);
563 * LOCKING: must hold mod->lock
565 static int ican3_new_recv_msg(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
567 struct ican3_new_desc desc
;
568 void __iomem
*desc_addr
= mod
->dpm
+ (mod
->rx_num
* sizeof(desc
));
570 /* switch to the tohost queue, and read the buffer descriptor */
571 ican3_set_page(mod
, QUEUE_TOHOST
);
572 memcpy_fromio(&desc
, desc_addr
, sizeof(desc
));
574 if (!(desc
.control
& DESC_VALID
)) {
575 dev_dbg(mod
->dev
, "%s: no buffers to recv\n", __func__
);
579 /* switch to the data page, copy the data */
580 ican3_set_page(mod
, desc
.pointer
);
581 memcpy_fromio(msg
, mod
->dpm
, sizeof(*msg
));
583 /* switch back to the descriptor, toggle the valid bit, write it back */
584 ican3_set_page(mod
, QUEUE_TOHOST
);
585 desc
.control
^= DESC_VALID
;
586 memcpy_toio(desc_addr
, &desc
, sizeof(desc
));
588 /* update the rx number */
589 mod
->rx_num
= (desc
.control
& DESC_WRAP
) ? 0 : (mod
->rx_num
+ 1);
594 * Message Send / Recv Helpers
597 static int ican3_send_msg(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
602 spin_lock_irqsave(&mod
->lock
, flags
);
604 if (mod
->iftype
== 0)
605 ret
= ican3_old_send_msg(mod
, msg
);
607 ret
= ican3_new_send_msg(mod
, msg
);
609 spin_unlock_irqrestore(&mod
->lock
, flags
);
613 static int ican3_recv_msg(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
618 spin_lock_irqsave(&mod
->lock
, flags
);
620 if (mod
->iftype
== 0)
621 ret
= ican3_old_recv_msg(mod
, msg
);
623 ret
= ican3_new_recv_msg(mod
, msg
);
625 spin_unlock_irqrestore(&mod
->lock
, flags
);
630 * Quick Pre-constructed Messages
633 static int ican3_msg_connect(struct ican3_dev
*mod
)
635 struct ican3_msg msg
;
637 memset(&msg
, 0, sizeof(msg
));
638 msg
.spec
= MSG_CONNECTI
;
639 msg
.len
= cpu_to_le16(0);
641 return ican3_send_msg(mod
, &msg
);
644 static int ican3_msg_disconnect(struct ican3_dev
*mod
)
646 struct ican3_msg msg
;
648 memset(&msg
, 0, sizeof(msg
));
649 msg
.spec
= MSG_DISCONNECT
;
650 msg
.len
= cpu_to_le16(0);
652 return ican3_send_msg(mod
, &msg
);
655 static int ican3_msg_newhostif(struct ican3_dev
*mod
)
657 struct ican3_msg msg
;
660 memset(&msg
, 0, sizeof(msg
));
661 msg
.spec
= MSG_NEWHOSTIF
;
662 msg
.len
= cpu_to_le16(0);
664 /* If we're not using the old interface, switching seems bogus */
665 WARN_ON(mod
->iftype
!= 0);
667 ret
= ican3_send_msg(mod
, &msg
);
671 /* mark the module as using the new host interface */
676 static int ican3_msg_fasthostif(struct ican3_dev
*mod
)
678 struct ican3_msg msg
;
681 memset(&msg
, 0, sizeof(msg
));
682 msg
.spec
= MSG_INITFDPMQUEUE
;
683 msg
.len
= cpu_to_le16(8);
685 /* write the tohost queue start address */
686 addr
= DPM_PAGE_ADDR(mod
->fastrx_start
);
687 msg
.data
[0] = addr
& 0xff;
688 msg
.data
[1] = (addr
>> 8) & 0xff;
689 msg
.data
[2] = (addr
>> 16) & 0xff;
690 msg
.data
[3] = (addr
>> 24) & 0xff;
692 /* write the fromhost queue start address */
693 addr
= DPM_PAGE_ADDR(mod
->fasttx_start
);
694 msg
.data
[4] = addr
& 0xff;
695 msg
.data
[5] = (addr
>> 8) & 0xff;
696 msg
.data
[6] = (addr
>> 16) & 0xff;
697 msg
.data
[7] = (addr
>> 24) & 0xff;
699 /* If we're not using the new interface yet, we cannot do this */
700 WARN_ON(mod
->iftype
!= 1);
702 return ican3_send_msg(mod
, &msg
);
706 * Setup the CAN filter to either accept or reject all
707 * messages from the CAN bus.
709 static int ican3_set_id_filter(struct ican3_dev
*mod
, bool accept
)
711 struct ican3_msg msg
;
714 /* Standard Frame Format */
715 memset(&msg
, 0, sizeof(msg
));
716 msg
.spec
= MSG_SETAFILMASK
;
717 msg
.len
= cpu_to_le16(5);
718 msg
.data
[0] = 0x00; /* IDLo LSB */
719 msg
.data
[1] = 0x00; /* IDLo MSB */
720 msg
.data
[2] = 0xff; /* IDHi LSB */
721 msg
.data
[3] = 0x07; /* IDHi MSB */
723 /* accept all frames for fast host if, or reject all frames */
724 msg
.data
[4] = accept
? SETAFILMASK_FASTIF
: SETAFILMASK_REJECT
;
726 ret
= ican3_send_msg(mod
, &msg
);
730 /* Extended Frame Format */
731 memset(&msg
, 0, sizeof(msg
));
732 msg
.spec
= MSG_SETAFILMASK
;
733 msg
.len
= cpu_to_le16(13);
734 msg
.data
[0] = 0; /* MUX = 0 */
735 msg
.data
[1] = 0x00; /* IDLo LSB */
738 msg
.data
[4] = 0x20; /* IDLo MSB */
739 msg
.data
[5] = 0xff; /* IDHi LSB */
742 msg
.data
[8] = 0x3f; /* IDHi MSB */
744 /* accept all frames for fast host if, or reject all frames */
745 msg
.data
[9] = accept
? SETAFILMASK_FASTIF
: SETAFILMASK_REJECT
;
747 return ican3_send_msg(mod
, &msg
);
751 * Bring the CAN bus online or offline
753 static int ican3_set_bus_state(struct ican3_dev
*mod
, bool on
)
755 struct ican3_msg msg
;
757 memset(&msg
, 0, sizeof(msg
));
758 msg
.spec
= on
? MSG_CONREQ
: MSG_COFFREQ
;
759 msg
.len
= cpu_to_le16(0);
761 return ican3_send_msg(mod
, &msg
);
764 static int ican3_set_termination(struct ican3_dev
*mod
, bool on
)
766 struct ican3_msg msg
;
768 memset(&msg
, 0, sizeof(msg
));
769 msg
.spec
= MSG_HWCONF
;
770 msg
.len
= cpu_to_le16(2);
772 msg
.data
[1] = on
? HWCONF_TERMINATE_ON
: HWCONF_TERMINATE_OFF
;
774 return ican3_send_msg(mod
, &msg
);
777 static int ican3_send_inquiry(struct ican3_dev
*mod
, u8 subspec
)
779 struct ican3_msg msg
;
781 memset(&msg
, 0, sizeof(msg
));
782 msg
.spec
= MSG_INQUIRY
;
783 msg
.len
= cpu_to_le16(2);
784 msg
.data
[0] = subspec
;
787 return ican3_send_msg(mod
, &msg
);
790 static int ican3_set_buserror(struct ican3_dev
*mod
, u8 quota
)
792 struct ican3_msg msg
;
794 memset(&msg
, 0, sizeof(msg
));
795 msg
.spec
= MSG_CCONFREQ
;
796 msg
.len
= cpu_to_le16(2);
800 return ican3_send_msg(mod
, &msg
);
804 * ICAN3 to Linux CAN Frame Conversion
807 static void ican3_to_can_frame(struct ican3_dev
*mod
,
808 struct ican3_fast_desc
*desc
,
809 struct can_frame
*cf
)
811 if ((desc
->command
& ICAN3_CAN_TYPE_MASK
) == ICAN3_CAN_TYPE_SFF
) {
812 if (desc
->data
[1] & ICAN3_SFF_RTR
)
813 cf
->can_id
|= CAN_RTR_FLAG
;
815 cf
->can_id
|= desc
->data
[0] << 3;
816 cf
->can_id
|= (desc
->data
[1] & 0xe0) >> 5;
817 cf
->can_dlc
= get_can_dlc(desc
->data
[1] & ICAN3_CAN_DLC_MASK
);
818 memcpy(cf
->data
, &desc
->data
[2], cf
->can_dlc
);
820 cf
->can_dlc
= get_can_dlc(desc
->data
[0] & ICAN3_CAN_DLC_MASK
);
821 if (desc
->data
[0] & ICAN3_EFF_RTR
)
822 cf
->can_id
|= CAN_RTR_FLAG
;
824 if (desc
->data
[0] & ICAN3_EFF
) {
825 cf
->can_id
|= CAN_EFF_FLAG
;
826 cf
->can_id
|= desc
->data
[2] << 21; /* 28-21 */
827 cf
->can_id
|= desc
->data
[3] << 13; /* 20-13 */
828 cf
->can_id
|= desc
->data
[4] << 5; /* 12-5 */
829 cf
->can_id
|= (desc
->data
[5] & 0xf8) >> 3;
831 cf
->can_id
|= desc
->data
[2] << 3; /* 10-3 */
832 cf
->can_id
|= desc
->data
[3] >> 5; /* 2-0 */
835 memcpy(cf
->data
, &desc
->data
[6], cf
->can_dlc
);
839 static void can_frame_to_ican3(struct ican3_dev
*mod
,
840 struct can_frame
*cf
,
841 struct ican3_fast_desc
*desc
)
843 /* clear out any stale data in the descriptor */
844 memset(desc
->data
, 0, sizeof(desc
->data
));
846 /* we always use the extended format, with the ECHO flag set */
847 desc
->command
= ICAN3_CAN_TYPE_EFF
;
848 desc
->data
[0] |= cf
->can_dlc
;
849 desc
->data
[1] |= ICAN3_ECHO
;
851 /* support single transmission (no retries) mode */
852 if (mod
->can
.ctrlmode
& CAN_CTRLMODE_ONE_SHOT
)
853 desc
->data
[1] |= ICAN3_SNGL
;
855 if (cf
->can_id
& CAN_RTR_FLAG
)
856 desc
->data
[0] |= ICAN3_EFF_RTR
;
858 /* pack the id into the correct places */
859 if (cf
->can_id
& CAN_EFF_FLAG
) {
860 desc
->data
[0] |= ICAN3_EFF
;
861 desc
->data
[2] = (cf
->can_id
& 0x1fe00000) >> 21; /* 28-21 */
862 desc
->data
[3] = (cf
->can_id
& 0x001fe000) >> 13; /* 20-13 */
863 desc
->data
[4] = (cf
->can_id
& 0x00001fe0) >> 5; /* 12-5 */
864 desc
->data
[5] = (cf
->can_id
& 0x0000001f) << 3; /* 4-0 */
866 desc
->data
[2] = (cf
->can_id
& 0x7F8) >> 3; /* bits 10-3 */
867 desc
->data
[3] = (cf
->can_id
& 0x007) << 5; /* bits 2-0 */
870 /* copy the data bits into the descriptor */
871 memcpy(&desc
->data
[6], cf
->data
, cf
->can_dlc
);
879 * Handle an ID + Version message response from the firmware. We never generate
880 * this message in production code, but it is very useful when debugging to be
881 * able to display this message.
883 static void ican3_handle_idvers(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
885 dev_dbg(mod
->dev
, "IDVERS response: %s\n", msg
->data
);
888 static void ican3_handle_msglost(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
890 struct net_device
*dev
= mod
->ndev
;
891 struct net_device_stats
*stats
= &dev
->stats
;
892 struct can_frame
*cf
;
896 * Report that communication messages with the microcontroller firmware
897 * are being lost. These are never CAN frames, so we do not generate an
898 * error frame for userspace
900 if (msg
->spec
== MSG_MSGLOST
) {
901 dev_err(mod
->dev
, "lost %d control messages\n", msg
->data
[0]);
906 * Oops, this indicates that we have lost messages in the fast queue,
907 * which are exclusively CAN messages. Our driver isn't reading CAN
908 * frames fast enough.
910 * We'll pretend that the SJA1000 told us that it ran out of buffer
911 * space, because there is not a better message for this.
913 skb
= alloc_can_err_skb(dev
, &cf
);
915 cf
->can_id
|= CAN_ERR_CRTL
;
916 cf
->data
[1] = CAN_ERR_CRTL_RX_OVERFLOW
;
917 stats
->rx_over_errors
++;
924 * Handle CAN Event Indication Messages from the firmware
926 * The ICAN3 firmware provides the values of some SJA1000 registers when it
927 * generates this message. The code below is largely copied from the
928 * drivers/net/can/sja1000/sja1000.c file, and adapted as necessary
930 static int ican3_handle_cevtind(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
932 struct net_device
*dev
= mod
->ndev
;
933 struct net_device_stats
*stats
= &dev
->stats
;
934 enum can_state state
= mod
->can
.state
;
935 u8 isrc
, ecc
, status
, rxerr
, txerr
;
936 struct can_frame
*cf
;
939 /* we can only handle the SJA1000 part */
940 if (msg
->data
[1] != CEVTIND_CHIP_SJA1000
) {
941 dev_err(mod
->dev
, "unable to handle errors on non-SJA1000\n");
945 /* check the message length for sanity */
946 if (le16_to_cpu(msg
->len
) < 6) {
947 dev_err(mod
->dev
, "error message too short\n");
953 status
= msg
->data
[3];
954 rxerr
= msg
->data
[4];
955 txerr
= msg
->data
[5];
958 * This hardware lacks any support other than bus error messages to
959 * determine if packet transmission has failed.
961 * When TX errors happen, one echo skb needs to be dropped from the
962 * front of the queue.
964 * A small bit of code is duplicated here and below, to avoid error
965 * skb allocation when it will just be freed immediately.
967 if (isrc
== CEVTIND_BEI
) {
969 dev_dbg(mod
->dev
, "bus error interrupt\n");
972 if (!(ecc
& ECC_DIR
)) {
973 kfree_skb(skb_dequeue(&mod
->echoq
));
980 * The controller automatically disables bus-error interrupts
981 * and therefore we must re-enable them.
983 ret
= ican3_set_buserror(mod
, 1);
985 dev_err(mod
->dev
, "unable to re-enable bus-error\n");
989 /* bus error reporting is off, return immediately */
990 if (!(mod
->can
.ctrlmode
& CAN_CTRLMODE_BERR_REPORTING
))
994 skb
= alloc_can_err_skb(dev
, &cf
);
998 /* data overrun interrupt */
999 if (isrc
== CEVTIND_DOI
|| isrc
== CEVTIND_LOST
) {
1000 dev_dbg(mod
->dev
, "data overrun interrupt\n");
1001 cf
->can_id
|= CAN_ERR_CRTL
;
1002 cf
->data
[1] = CAN_ERR_CRTL_RX_OVERFLOW
;
1003 stats
->rx_over_errors
++;
1007 /* error warning + passive interrupt */
1008 if (isrc
== CEVTIND_EI
) {
1009 dev_dbg(mod
->dev
, "error warning + passive interrupt\n");
1010 if (status
& SR_BS
) {
1011 state
= CAN_STATE_BUS_OFF
;
1012 cf
->can_id
|= CAN_ERR_BUSOFF
;
1014 } else if (status
& SR_ES
) {
1015 if (rxerr
>= 128 || txerr
>= 128)
1016 state
= CAN_STATE_ERROR_PASSIVE
;
1018 state
= CAN_STATE_ERROR_WARNING
;
1020 state
= CAN_STATE_ERROR_ACTIVE
;
1024 /* bus error interrupt */
1025 if (isrc
== CEVTIND_BEI
) {
1026 mod
->can
.can_stats
.bus_error
++;
1027 cf
->can_id
|= CAN_ERR_PROT
| CAN_ERR_BUSERROR
;
1029 switch (ecc
& ECC_MASK
) {
1031 cf
->data
[2] |= CAN_ERR_PROT_BIT
;
1034 cf
->data
[2] |= CAN_ERR_PROT_FORM
;
1037 cf
->data
[2] |= CAN_ERR_PROT_STUFF
;
1040 cf
->data
[2] |= CAN_ERR_PROT_UNSPEC
;
1041 cf
->data
[3] = ecc
& ECC_SEG
;
1045 if (!(ecc
& ECC_DIR
))
1046 cf
->data
[2] |= CAN_ERR_PROT_TX
;
1048 cf
->data
[6] = txerr
;
1049 cf
->data
[7] = rxerr
;
1052 if (state
!= mod
->can
.state
&& (state
== CAN_STATE_ERROR_WARNING
||
1053 state
== CAN_STATE_ERROR_PASSIVE
)) {
1054 cf
->can_id
|= CAN_ERR_CRTL
;
1055 if (state
== CAN_STATE_ERROR_WARNING
) {
1056 mod
->can
.can_stats
.error_warning
++;
1057 cf
->data
[1] = (txerr
> rxerr
) ?
1058 CAN_ERR_CRTL_TX_WARNING
:
1059 CAN_ERR_CRTL_RX_WARNING
;
1061 mod
->can
.can_stats
.error_passive
++;
1062 cf
->data
[1] = (txerr
> rxerr
) ?
1063 CAN_ERR_CRTL_TX_PASSIVE
:
1064 CAN_ERR_CRTL_RX_PASSIVE
;
1067 cf
->data
[6] = txerr
;
1068 cf
->data
[7] = rxerr
;
1071 mod
->can
.state
= state
;
1076 static void ican3_handle_inquiry(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
1078 switch (msg
->data
[0]) {
1079 case INQUIRY_STATUS
:
1080 case INQUIRY_EXTENDED
:
1081 mod
->bec
.rxerr
= msg
->data
[5];
1082 mod
->bec
.txerr
= msg
->data
[6];
1083 complete(&mod
->buserror_comp
);
1085 case INQUIRY_TERMINATION
:
1086 mod
->termination_enabled
= msg
->data
[6] & HWCONF_TERMINATE_ON
;
1087 complete(&mod
->termination_comp
);
1090 dev_err(mod
->dev
, "received an unknown inquiry response\n");
1095 static void ican3_handle_unknown_message(struct ican3_dev
*mod
,
1096 struct ican3_msg
*msg
)
1098 dev_warn(mod
->dev
, "received unknown message: spec 0x%.2x length %d\n",
1099 msg
->spec
, le16_to_cpu(msg
->len
));
1103 * Handle a control message from the firmware
1105 static void ican3_handle_message(struct ican3_dev
*mod
, struct ican3_msg
*msg
)
1107 dev_dbg(mod
->dev
, "%s: modno %d spec 0x%.2x len %d bytes\n", __func__
,
1108 mod
->num
, msg
->spec
, le16_to_cpu(msg
->len
));
1110 switch (msg
->spec
) {
1112 ican3_handle_idvers(mod
, msg
);
1116 ican3_handle_msglost(mod
, msg
);
1119 ican3_handle_cevtind(mod
, msg
);
1122 ican3_handle_inquiry(mod
, msg
);
1125 ican3_handle_unknown_message(mod
, msg
);
1131 * The ican3 needs to store all echo skbs, and therefore cannot
1132 * use the generic infrastructure for this.
1134 static void ican3_put_echo_skb(struct ican3_dev
*mod
, struct sk_buff
*skb
)
1136 struct sock
*srcsk
= skb
->sk
;
1138 if (atomic_read(&skb
->users
) != 1) {
1139 struct sk_buff
*old_skb
= skb
;
1141 skb
= skb_clone(old_skb
, GFP_ATOMIC
);
1151 /* save this skb for tx interrupt echo handling */
1152 skb_queue_tail(&mod
->echoq
, skb
);
1155 static unsigned int ican3_get_echo_skb(struct ican3_dev
*mod
)
1157 struct sk_buff
*skb
= skb_dequeue(&mod
->echoq
);
1158 struct can_frame
*cf
;
1161 /* this should never trigger unless there is a driver bug */
1163 netdev_err(mod
->ndev
, "BUG: echo skb not occupied\n");
1167 cf
= (struct can_frame
*)skb
->data
;
1170 /* check flag whether this packet has to be looped back */
1171 if (skb
->pkt_type
!= PACKET_LOOPBACK
) {
1176 skb
->protocol
= htons(ETH_P_CAN
);
1177 skb
->pkt_type
= PACKET_BROADCAST
;
1178 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
1179 skb
->dev
= mod
->ndev
;
1180 netif_receive_skb(skb
);
1185 * Compare an skb with an existing echo skb
1187 * This function will be used on devices which have a hardware loopback.
1188 * On these devices, this function can be used to compare a received skb
1189 * with the saved echo skbs so that the hardware echo skb can be dropped.
1191 * Returns true if the skb's are identical, false otherwise.
1193 static bool ican3_echo_skb_matches(struct ican3_dev
*mod
, struct sk_buff
*skb
)
1195 struct can_frame
*cf
= (struct can_frame
*)skb
->data
;
1196 struct sk_buff
*echo_skb
= skb_peek(&mod
->echoq
);
1197 struct can_frame
*echo_cf
;
1202 echo_cf
= (struct can_frame
*)echo_skb
->data
;
1203 if (cf
->can_id
!= echo_cf
->can_id
)
1206 if (cf
->can_dlc
!= echo_cf
->can_dlc
)
1209 return memcmp(cf
->data
, echo_cf
->data
, cf
->can_dlc
) == 0;
1213 * Check that there is room in the TX ring to transmit another skb
1215 * LOCKING: must hold mod->lock
1217 static bool ican3_txok(struct ican3_dev
*mod
)
1219 struct ican3_fast_desc __iomem
*desc
;
1222 /* check that we have echo queue space */
1223 if (skb_queue_len(&mod
->echoq
) >= ICAN3_TX_BUFFERS
)
1226 /* copy the control bits of the descriptor */
1227 ican3_set_page(mod
, mod
->fasttx_start
+ (mod
->fasttx_num
/ 16));
1228 desc
= mod
->dpm
+ ((mod
->fasttx_num
% 16) * sizeof(*desc
));
1229 control
= ioread8(&desc
->control
);
1231 /* if the control bits are not valid, then we have no more space */
1232 if (!(control
& DESC_VALID
))
1239 * Receive one CAN frame from the hardware
1241 * CONTEXT: must be called from user context
1243 static int ican3_recv_skb(struct ican3_dev
*mod
)
1245 struct net_device
*ndev
= mod
->ndev
;
1246 struct net_device_stats
*stats
= &ndev
->stats
;
1247 struct ican3_fast_desc desc
;
1248 void __iomem
*desc_addr
;
1249 struct can_frame
*cf
;
1250 struct sk_buff
*skb
;
1251 unsigned long flags
;
1253 spin_lock_irqsave(&mod
->lock
, flags
);
1255 /* copy the whole descriptor */
1256 ican3_set_page(mod
, mod
->fastrx_start
+ (mod
->fastrx_num
/ 16));
1257 desc_addr
= mod
->dpm
+ ((mod
->fastrx_num
% 16) * sizeof(desc
));
1258 memcpy_fromio(&desc
, desc_addr
, sizeof(desc
));
1260 spin_unlock_irqrestore(&mod
->lock
, flags
);
1262 /* check that we actually have a CAN frame */
1263 if (!(desc
.control
& DESC_VALID
))
1266 /* allocate an skb */
1267 skb
= alloc_can_skb(ndev
, &cf
);
1268 if (unlikely(skb
== NULL
)) {
1269 stats
->rx_dropped
++;
1273 /* convert the ICAN3 frame into Linux CAN format */
1274 ican3_to_can_frame(mod
, &desc
, cf
);
1277 * If this is an ECHO frame received from the hardware loopback
1278 * feature, use the skb saved in the ECHO stack instead. This allows
1279 * the Linux CAN core to support CAN_RAW_RECV_OWN_MSGS correctly.
1281 * Since this is a confirmation of a successfully transmitted packet
1282 * sent from this host, update the transmit statistics.
1284 * Also, the netdevice queue needs to be allowed to send packets again.
1286 if (ican3_echo_skb_matches(mod
, skb
)) {
1287 stats
->tx_packets
++;
1288 stats
->tx_bytes
+= ican3_get_echo_skb(mod
);
1293 /* update statistics, receive the skb */
1294 stats
->rx_packets
++;
1295 stats
->rx_bytes
+= cf
->can_dlc
;
1296 netif_receive_skb(skb
);
1299 /* toggle the valid bit and return the descriptor to the ring */
1300 desc
.control
^= DESC_VALID
;
1302 spin_lock_irqsave(&mod
->lock
, flags
);
1304 ican3_set_page(mod
, mod
->fastrx_start
+ (mod
->fastrx_num
/ 16));
1305 memcpy_toio(desc_addr
, &desc
, 1);
1307 /* update the next buffer pointer */
1308 mod
->fastrx_num
= (desc
.control
& DESC_WRAP
) ? 0
1309 : (mod
->fastrx_num
+ 1);
1311 /* there are still more buffers to process */
1312 spin_unlock_irqrestore(&mod
->lock
, flags
);
1316 static int ican3_napi(struct napi_struct
*napi
, int budget
)
1318 struct ican3_dev
*mod
= container_of(napi
, struct ican3_dev
, napi
);
1319 unsigned long flags
;
1323 /* process all communication messages */
1325 struct ican3_msg msg
;
1326 ret
= ican3_recv_msg(mod
, &msg
);
1330 ican3_handle_message(mod
, &msg
);
1333 /* process all CAN frames from the fast interface */
1334 while (received
< budget
) {
1335 ret
= ican3_recv_skb(mod
);
1342 /* We have processed all packets that the adapter had, but it
1343 * was less than our budget, stop polling */
1344 if (received
< budget
)
1345 napi_complete(napi
);
1347 spin_lock_irqsave(&mod
->lock
, flags
);
1349 /* Wake up the transmit queue if necessary */
1350 if (netif_queue_stopped(mod
->ndev
) && ican3_txok(mod
))
1351 netif_wake_queue(mod
->ndev
);
1353 spin_unlock_irqrestore(&mod
->lock
, flags
);
1355 /* re-enable interrupt generation */
1356 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_enable
);
1360 static irqreturn_t
ican3_irq(int irq
, void *dev_id
)
1362 struct ican3_dev
*mod
= dev_id
;
1366 * The interrupt status register on this device reports interrupts
1367 * as zeroes instead of using ones like most other devices
1369 stat
= ioread8(&mod
->ctrl
->int_disable
) & (1 << mod
->num
);
1370 if (stat
== (1 << mod
->num
))
1373 /* clear the MODULbus interrupt from the microcontroller */
1374 ioread8(&mod
->dpmctrl
->interrupt
);
1376 /* disable interrupt generation, schedule the NAPI poller */
1377 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_disable
);
1378 napi_schedule(&mod
->napi
);
1383 * Firmware reset, startup, and shutdown
1387 * Reset an ICAN module to its power-on state
1389 * CONTEXT: no network device registered
1391 static int ican3_reset_module(struct ican3_dev
*mod
)
1393 unsigned long start
;
1396 /* disable interrupts so no more work is scheduled */
1397 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_disable
);
1399 /* the first unallocated page in the DPM is #9 */
1400 mod
->free_page
= DPM_FREE_START
;
1402 ican3_set_page(mod
, QUEUE_OLD_CONTROL
);
1403 runold
= ioread8(mod
->dpm
+ TARGET_RUNNING
);
1405 /* reset the module */
1406 iowrite8(0x00, &mod
->dpmctrl
->hwreset
);
1408 /* wait until the module has finished resetting and is running */
1411 ican3_set_page(mod
, QUEUE_OLD_CONTROL
);
1412 runnew
= ioread8(mod
->dpm
+ TARGET_RUNNING
);
1413 if (runnew
== (runold
^ 0xff))
1417 } while (time_before(jiffies
, start
+ HZ
/ 4));
1419 dev_err(mod
->dev
, "failed to reset CAN module\n");
1423 static void ican3_shutdown_module(struct ican3_dev
*mod
)
1425 ican3_msg_disconnect(mod
);
1426 ican3_reset_module(mod
);
1430 * Startup an ICAN module, bringing it into fast mode
1432 static int ican3_startup_module(struct ican3_dev
*mod
)
1436 ret
= ican3_reset_module(mod
);
1438 dev_err(mod
->dev
, "unable to reset module\n");
1442 /* re-enable interrupts so we can send messages */
1443 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_enable
);
1445 ret
= ican3_msg_connect(mod
);
1447 dev_err(mod
->dev
, "unable to connect to module\n");
1451 ican3_init_new_host_interface(mod
);
1452 ret
= ican3_msg_newhostif(mod
);
1454 dev_err(mod
->dev
, "unable to switch to new-style interface\n");
1458 /* default to "termination on" */
1459 ret
= ican3_set_termination(mod
, true);
1461 dev_err(mod
->dev
, "unable to enable termination\n");
1465 /* default to "bus errors enabled" */
1466 ret
= ican3_set_buserror(mod
, 1);
1468 dev_err(mod
->dev
, "unable to set bus-error\n");
1472 ican3_init_fast_host_interface(mod
);
1473 ret
= ican3_msg_fasthostif(mod
);
1475 dev_err(mod
->dev
, "unable to switch to fast host interface\n");
1479 ret
= ican3_set_id_filter(mod
, true);
1481 dev_err(mod
->dev
, "unable to set acceptance filter\n");
1489 * CAN Network Device
1492 static int ican3_open(struct net_device
*ndev
)
1494 struct ican3_dev
*mod
= netdev_priv(ndev
);
1497 /* open the CAN layer */
1498 ret
= open_candev(ndev
);
1500 dev_err(mod
->dev
, "unable to start CAN layer\n");
1504 /* bring the bus online */
1505 ret
= ican3_set_bus_state(mod
, true);
1507 dev_err(mod
->dev
, "unable to set bus-on\n");
1512 /* start up the network device */
1513 mod
->can
.state
= CAN_STATE_ERROR_ACTIVE
;
1514 netif_start_queue(ndev
);
1519 static int ican3_stop(struct net_device
*ndev
)
1521 struct ican3_dev
*mod
= netdev_priv(ndev
);
1524 /* stop the network device xmit routine */
1525 netif_stop_queue(ndev
);
1526 mod
->can
.state
= CAN_STATE_STOPPED
;
1528 /* bring the bus offline, stop receiving packets */
1529 ret
= ican3_set_bus_state(mod
, false);
1531 dev_err(mod
->dev
, "unable to set bus-off\n");
1535 /* drop all outstanding echo skbs */
1536 skb_queue_purge(&mod
->echoq
);
1538 /* close the CAN layer */
1543 static int ican3_xmit(struct sk_buff
*skb
, struct net_device
*ndev
)
1545 struct ican3_dev
*mod
= netdev_priv(ndev
);
1546 struct can_frame
*cf
= (struct can_frame
*)skb
->data
;
1547 struct ican3_fast_desc desc
;
1548 void __iomem
*desc_addr
;
1549 unsigned long flags
;
1551 if (can_dropped_invalid_skb(ndev
, skb
))
1552 return NETDEV_TX_OK
;
1554 spin_lock_irqsave(&mod
->lock
, flags
);
1556 /* check that we can actually transmit */
1557 if (!ican3_txok(mod
)) {
1558 dev_err(mod
->dev
, "BUG: no free descriptors\n");
1559 spin_unlock_irqrestore(&mod
->lock
, flags
);
1560 return NETDEV_TX_BUSY
;
1563 /* copy the control bits of the descriptor */
1564 ican3_set_page(mod
, mod
->fasttx_start
+ (mod
->fasttx_num
/ 16));
1565 desc_addr
= mod
->dpm
+ ((mod
->fasttx_num
% 16) * sizeof(desc
));
1566 memset(&desc
, 0, sizeof(desc
));
1567 memcpy_fromio(&desc
, desc_addr
, 1);
1569 /* convert the Linux CAN frame into ICAN3 format */
1570 can_frame_to_ican3(mod
, cf
, &desc
);
1573 * This hardware doesn't have TX-done notifications, so we'll try and
1574 * emulate it the best we can using ECHO skbs. Add the skb to the ECHO
1575 * stack. Upon packet reception, check if the ECHO skb and received
1576 * skb match, and use that to wake the queue.
1578 ican3_put_echo_skb(mod
, skb
);
1581 * the programming manual says that you must set the IVALID bit, then
1582 * interrupt, then set the valid bit. Quite weird, but it seems to be
1583 * required for this to work
1585 desc
.control
|= DESC_IVALID
;
1586 memcpy_toio(desc_addr
, &desc
, sizeof(desc
));
1588 /* generate a MODULbus interrupt to the microcontroller */
1589 iowrite8(0x01, &mod
->dpmctrl
->interrupt
);
1591 desc
.control
^= DESC_VALID
;
1592 memcpy_toio(desc_addr
, &desc
, sizeof(desc
));
1594 /* update the next buffer pointer */
1595 mod
->fasttx_num
= (desc
.control
& DESC_WRAP
) ? 0
1596 : (mod
->fasttx_num
+ 1);
1598 /* if there is no free descriptor space, stop the transmit queue */
1599 if (!ican3_txok(mod
))
1600 netif_stop_queue(ndev
);
1602 spin_unlock_irqrestore(&mod
->lock
, flags
);
1603 return NETDEV_TX_OK
;
1606 static const struct net_device_ops ican3_netdev_ops
= {
1607 .ndo_open
= ican3_open
,
1608 .ndo_stop
= ican3_stop
,
1609 .ndo_start_xmit
= ican3_xmit
,
1613 * Low-level CAN Device
1616 /* This structure was stolen from drivers/net/can/sja1000/sja1000.c */
1617 static const struct can_bittiming_const ican3_bittiming_const
= {
1630 * This routine was stolen from drivers/net/can/sja1000/sja1000.c
1632 * The bittiming register command for the ICAN3 just sets the bit timing
1633 * registers on the SJA1000 chip directly
1635 static int ican3_set_bittiming(struct net_device
*ndev
)
1637 struct ican3_dev
*mod
= netdev_priv(ndev
);
1638 struct can_bittiming
*bt
= &mod
->can
.bittiming
;
1639 struct ican3_msg msg
;
1642 btr0
= ((bt
->brp
- 1) & 0x3f) | (((bt
->sjw
- 1) & 0x3) << 6);
1643 btr1
= ((bt
->prop_seg
+ bt
->phase_seg1
- 1) & 0xf) |
1644 (((bt
->phase_seg2
- 1) & 0x7) << 4);
1645 if (mod
->can
.ctrlmode
& CAN_CTRLMODE_3_SAMPLES
)
1648 memset(&msg
, 0, sizeof(msg
));
1649 msg
.spec
= MSG_CBTRREQ
;
1650 msg
.len
= cpu_to_le16(4);
1656 return ican3_send_msg(mod
, &msg
);
1659 static int ican3_set_mode(struct net_device
*ndev
, enum can_mode mode
)
1661 struct ican3_dev
*mod
= netdev_priv(ndev
);
1664 if (mode
!= CAN_MODE_START
)
1667 /* bring the bus online */
1668 ret
= ican3_set_bus_state(mod
, true);
1670 dev_err(mod
->dev
, "unable to set bus-on\n");
1674 /* start up the network device */
1675 mod
->can
.state
= CAN_STATE_ERROR_ACTIVE
;
1677 if (netif_queue_stopped(ndev
))
1678 netif_wake_queue(ndev
);
1683 static int ican3_get_berr_counter(const struct net_device
*ndev
,
1684 struct can_berr_counter
*bec
)
1686 struct ican3_dev
*mod
= netdev_priv(ndev
);
1689 ret
= ican3_send_inquiry(mod
, INQUIRY_STATUS
);
1693 ret
= wait_for_completion_timeout(&mod
->buserror_comp
, HZ
);
1695 dev_info(mod
->dev
, "%s timed out\n", __func__
);
1699 bec
->rxerr
= mod
->bec
.rxerr
;
1700 bec
->txerr
= mod
->bec
.txerr
;
1708 static ssize_t
ican3_sysfs_show_term(struct device
*dev
,
1709 struct device_attribute
*attr
,
1712 struct ican3_dev
*mod
= netdev_priv(to_net_dev(dev
));
1715 ret
= ican3_send_inquiry(mod
, INQUIRY_TERMINATION
);
1719 ret
= wait_for_completion_timeout(&mod
->termination_comp
, HZ
);
1721 dev_info(mod
->dev
, "%s timed out\n", __func__
);
1725 return snprintf(buf
, PAGE_SIZE
, "%u\n", mod
->termination_enabled
);
1728 static ssize_t
ican3_sysfs_set_term(struct device
*dev
,
1729 struct device_attribute
*attr
,
1730 const char *buf
, size_t count
)
1732 struct ican3_dev
*mod
= netdev_priv(to_net_dev(dev
));
1733 unsigned long enable
;
1736 if (kstrtoul(buf
, 0, &enable
))
1739 ret
= ican3_set_termination(mod
, enable
);
1746 static DEVICE_ATTR(termination
, S_IWUSR
| S_IRUGO
, ican3_sysfs_show_term
,
1747 ican3_sysfs_set_term
);
1749 static struct attribute
*ican3_sysfs_attrs
[] = {
1750 &dev_attr_termination
.attr
,
1754 static struct attribute_group ican3_sysfs_attr_group
= {
1755 .attrs
= ican3_sysfs_attrs
,
1762 static int ican3_probe(struct platform_device
*pdev
)
1764 struct janz_platform_data
*pdata
;
1765 struct net_device
*ndev
;
1766 struct ican3_dev
*mod
;
1767 struct resource
*res
;
1771 pdata
= dev_get_platdata(&pdev
->dev
);
1775 dev_dbg(&pdev
->dev
, "probe: module number %d\n", pdata
->modno
);
1777 /* save the struct device for printing */
1780 /* allocate the CAN device and private data */
1781 ndev
= alloc_candev(sizeof(*mod
), 0);
1783 dev_err(dev
, "unable to allocate CANdev\n");
1788 platform_set_drvdata(pdev
, ndev
);
1789 mod
= netdev_priv(ndev
);
1791 mod
->dev
= &pdev
->dev
;
1792 mod
->num
= pdata
->modno
;
1793 netif_napi_add(ndev
, &mod
->napi
, ican3_napi
, ICAN3_RX_BUFFERS
);
1794 skb_queue_head_init(&mod
->echoq
);
1795 spin_lock_init(&mod
->lock
);
1796 init_completion(&mod
->termination_comp
);
1797 init_completion(&mod
->buserror_comp
);
1799 /* setup device-specific sysfs attributes */
1800 ndev
->sysfs_groups
[0] = &ican3_sysfs_attr_group
;
1802 /* the first unallocated page in the DPM is 9 */
1803 mod
->free_page
= DPM_FREE_START
;
1805 ndev
->netdev_ops
= &ican3_netdev_ops
;
1806 ndev
->flags
|= IFF_ECHO
;
1807 SET_NETDEV_DEV(ndev
, &pdev
->dev
);
1809 mod
->can
.clock
.freq
= ICAN3_CAN_CLOCK
;
1810 mod
->can
.bittiming_const
= &ican3_bittiming_const
;
1811 mod
->can
.do_set_bittiming
= ican3_set_bittiming
;
1812 mod
->can
.do_set_mode
= ican3_set_mode
;
1813 mod
->can
.do_get_berr_counter
= ican3_get_berr_counter
;
1814 mod
->can
.ctrlmode_supported
= CAN_CTRLMODE_3_SAMPLES
1815 | CAN_CTRLMODE_BERR_REPORTING
1816 | CAN_CTRLMODE_ONE_SHOT
;
1818 /* find our IRQ number */
1819 mod
->irq
= platform_get_irq(pdev
, 0);
1821 dev_err(dev
, "IRQ line not found\n");
1826 ndev
->irq
= mod
->irq
;
1828 /* get access to the MODULbus registers for this module */
1829 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
1831 dev_err(dev
, "MODULbus registers not found\n");
1836 mod
->dpm
= ioremap(res
->start
, resource_size(res
));
1838 dev_err(dev
, "MODULbus registers not ioremap\n");
1843 mod
->dpmctrl
= mod
->dpm
+ DPM_PAGE_SIZE
;
1845 /* get access to the control registers for this module */
1846 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 1);
1848 dev_err(dev
, "CONTROL registers not found\n");
1850 goto out_iounmap_dpm
;
1853 mod
->ctrl
= ioremap(res
->start
, resource_size(res
));
1855 dev_err(dev
, "CONTROL registers not ioremap\n");
1857 goto out_iounmap_dpm
;
1860 /* disable our IRQ, then hookup the IRQ handler */
1861 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_disable
);
1862 ret
= request_irq(mod
->irq
, ican3_irq
, IRQF_SHARED
, DRV_NAME
, mod
);
1864 dev_err(dev
, "unable to request IRQ\n");
1865 goto out_iounmap_ctrl
;
1868 /* reset and initialize the CAN controller into fast mode */
1869 napi_enable(&mod
->napi
);
1870 ret
= ican3_startup_module(mod
);
1872 dev_err(dev
, "%s: unable to start CANdev\n", __func__
);
1876 /* register with the Linux CAN layer */
1877 ret
= register_candev(ndev
);
1879 dev_err(dev
, "%s: unable to register CANdev\n", __func__
);
1883 dev_info(dev
, "module %d: registered CAN device\n", pdata
->modno
);
1887 napi_disable(&mod
->napi
);
1888 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_disable
);
1889 free_irq(mod
->irq
, mod
);
1900 static int ican3_remove(struct platform_device
*pdev
)
1902 struct net_device
*ndev
= platform_get_drvdata(pdev
);
1903 struct ican3_dev
*mod
= netdev_priv(ndev
);
1905 /* unregister the netdevice, stop interrupts */
1906 unregister_netdev(ndev
);
1907 napi_disable(&mod
->napi
);
1908 iowrite8(1 << mod
->num
, &mod
->ctrl
->int_disable
);
1909 free_irq(mod
->irq
, mod
);
1911 /* put the module into reset */
1912 ican3_shutdown_module(mod
);
1914 /* unmap all registers */
1923 static struct platform_driver ican3_driver
= {
1926 .owner
= THIS_MODULE
,
1928 .probe
= ican3_probe
,
1929 .remove
= ican3_remove
,
1932 module_platform_driver(ican3_driver
);
1934 MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
1935 MODULE_DESCRIPTION("Janz MODULbus VMOD-ICAN3 Driver");
1936 MODULE_LICENSE("GPL");
1937 MODULE_ALIAS("platform:janz-ican3");