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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Janz MODULbus VMOD-ICAN3 CAN Interface Driver
4 *
5 * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/interrupt.h>
11#include <linux/delay.h>
12#include <linux/ethtool.h>
13#include <linux/platform_device.h>
14
15#include <linux/netdevice.h>
16#include <linux/can.h>
17#include <linux/can/dev.h>
18#include <linux/can/skb.h>
19#include <linux/can/error.h>
20
21#include <linux/mfd/janz.h>
22#include <asm/io.h>
23
24/* the DPM has 64k of memory, organized into 256x 256 byte pages */
25#define DPM_NUM_PAGES 256
26#define DPM_PAGE_SIZE 256
27#define DPM_PAGE_ADDR(p) ((p) * DPM_PAGE_SIZE)
28
29/* JANZ ICAN3 "old-style" host interface queue page numbers */
30#define QUEUE_OLD_CONTROL 0
31#define QUEUE_OLD_RB0 1
32#define QUEUE_OLD_RB1 2
33#define QUEUE_OLD_WB0 3
34#define QUEUE_OLD_WB1 4
35
36/* Janz ICAN3 "old-style" host interface control registers */
37#define MSYNC_PEER 0x00 /* ICAN only */
38#define MSYNC_LOCL 0x01 /* host only */
39#define TARGET_RUNNING 0x02
40#define FIRMWARE_STAMP 0x60 /* big endian firmware stamp */
41
42#define MSYNC_RB0 0x01
43#define MSYNC_RB1 0x02
44#define MSYNC_RBLW 0x04
45#define MSYNC_RB_MASK (MSYNC_RB0 | MSYNC_RB1)
46
47#define MSYNC_WB0 0x10
48#define MSYNC_WB1 0x20
49#define MSYNC_WBLW 0x40
50#define MSYNC_WB_MASK (MSYNC_WB0 | MSYNC_WB1)
51
52/* Janz ICAN3 "new-style" host interface queue page numbers */
53#define QUEUE_TOHOST 5
54#define QUEUE_FROMHOST_MID 6
55#define QUEUE_FROMHOST_HIGH 7
56#define QUEUE_FROMHOST_LOW 8
57
58/* The first free page in the DPM is #9 */
59#define DPM_FREE_START 9
60
61/* Janz ICAN3 "new-style" and "fast" host interface descriptor flags */
62#define DESC_VALID 0x80
63#define DESC_WRAP 0x40
64#define DESC_INTERRUPT 0x20
65#define DESC_IVALID 0x10
66#define DESC_LEN(len) (len)
67
68/* Janz ICAN3 Firmware Messages */
69#define MSG_CONNECTI 0x02
70#define MSG_DISCONNECT 0x03
71#define MSG_IDVERS 0x04
72#define MSG_MSGLOST 0x05
73#define MSG_NEWHOSTIF 0x08
74#define MSG_INQUIRY 0x0a
75#define MSG_SETAFILMASK 0x10
76#define MSG_INITFDPMQUEUE 0x11
77#define MSG_HWCONF 0x12
78#define MSG_FMSGLOST 0x15
79#define MSG_CEVTIND 0x37
80#define MSG_CBTRREQ 0x41
81#define MSG_COFFREQ 0x42
82#define MSG_CONREQ 0x43
83#define MSG_CCONFREQ 0x47
84#define MSG_NMTS 0xb0
85#define MSG_LMTS 0xb4
86
87/*
88 * Janz ICAN3 CAN Inquiry Message Types
89 *
90 * NOTE: there appears to be a firmware bug here. You must send
91 * NOTE: INQUIRY_STATUS and expect to receive an INQUIRY_EXTENDED
92 * NOTE: response. The controller never responds to a message with
93 * NOTE: the INQUIRY_EXTENDED subspec :(
94 */
95#define INQUIRY_STATUS 0x00
96#define INQUIRY_TERMINATION 0x01
97#define INQUIRY_EXTENDED 0x04
98
99/* Janz ICAN3 CAN Set Acceptance Filter Mask Message Types */
100#define SETAFILMASK_REJECT 0x00
101#define SETAFILMASK_FASTIF 0x02
102
103/* Janz ICAN3 CAN Hardware Configuration Message Types */
104#define HWCONF_TERMINATE_ON 0x01
105#define HWCONF_TERMINATE_OFF 0x00
106
107/* Janz ICAN3 CAN Event Indication Message Types */
108#define CEVTIND_EI 0x01
109#define CEVTIND_DOI 0x02
110#define CEVTIND_LOST 0x04
111#define CEVTIND_FULL 0x08
112#define CEVTIND_BEI 0x10
113
114#define CEVTIND_CHIP_SJA1000 0x02
115
116#define ICAN3_BUSERR_QUOTA_MAX 255
117
118/* Janz ICAN3 CAN Frame Conversion */
119#define ICAN3_SNGL 0x02
120#define ICAN3_ECHO 0x10
121#define ICAN3_EFF_RTR 0x40
122#define ICAN3_SFF_RTR 0x10
123#define ICAN3_EFF 0x80
124
125#define ICAN3_CAN_TYPE_MASK 0x0f
126#define ICAN3_CAN_TYPE_SFF 0x00
127#define ICAN3_CAN_TYPE_EFF 0x01
128
129#define ICAN3_CAN_DLC_MASK 0x0f
130
131/* Janz ICAN3 NMTS subtypes */
132#define NMTS_CREATE_NODE_REQ 0x0
133#define NMTS_SLAVE_STATE_IND 0x8
134#define NMTS_SLAVE_EVENT_IND 0x9
135
136/* Janz ICAN3 LMTS subtypes */
137#define LMTS_BUSON_REQ 0x0
138#define LMTS_BUSOFF_REQ 0x1
139#define LMTS_CAN_CONF_REQ 0x2
140
141/* Janz ICAN3 NMTS Event indications */
142#define NE_LOCAL_OCCURRED 0x3
143#define NE_LOCAL_RESOLVED 0x2
144#define NE_REMOTE_OCCURRED 0xc
145#define NE_REMOTE_RESOLVED 0x8
146
147/*
148 * SJA1000 Status and Error Register Definitions
149 *
150 * Copied from drivers/net/can/sja1000/sja1000.h
151 */
152
153/* status register content */
154#define SR_BS 0x80
155#define SR_ES 0x40
156#define SR_TS 0x20
157#define SR_RS 0x10
158#define SR_TCS 0x08
159#define SR_TBS 0x04
160#define SR_DOS 0x02
161#define SR_RBS 0x01
162
163#define SR_CRIT (SR_BS|SR_ES)
164
165/* ECC register */
166#define ECC_SEG 0x1F
167#define ECC_DIR 0x20
168#define ECC_ERR 6
169#define ECC_BIT 0x00
170#define ECC_FORM 0x40
171#define ECC_STUFF 0x80
172#define ECC_MASK 0xc0
173
174/* Number of buffers for use in the "new-style" host interface */
175#define ICAN3_NEW_BUFFERS 16
176
177/* Number of buffers for use in the "fast" host interface */
178#define ICAN3_TX_BUFFERS 512
179#define ICAN3_RX_BUFFERS 1024
180
181/* SJA1000 Clock Input */
182#define ICAN3_CAN_CLOCK 8000000
183
184/* Janz ICAN3 firmware types */
185enum ican3_fwtype {
186 ICAN3_FWTYPE_ICANOS,
187 ICAN3_FWTYPE_CAL_CANOPEN,
188};
189
190/* Driver Name */
191#define DRV_NAME "janz-ican3"
192
193/* DPM Control Registers -- starts at offset 0x100 in the MODULbus registers */
194struct ican3_dpm_control {
195 /* window address register */
196 u8 window_address;
197 u8 unused1;
198
199 /*
200 * Read access: clear interrupt from microcontroller
201 * Write access: send interrupt to microcontroller
202 */
203 u8 interrupt;
204 u8 unused2;
205
206 /* write-only: reset all hardware on the module */
207 u8 hwreset;
208 u8 unused3;
209
210 /* write-only: generate an interrupt to the TPU */
211 u8 tpuinterrupt;
212};
213
214struct ican3_dev {
215
216 /* must be the first member */
217 struct can_priv can;
218
219 /* CAN network device */
220 struct net_device *ndev;
221 struct napi_struct napi;
222
223 /* module number */
224 unsigned int num;
225
226 /* base address of registers and IRQ */
227 struct janz_cmodio_onboard_regs __iomem *ctrl;
228 struct ican3_dpm_control __iomem *dpmctrl;
229 void __iomem *dpm;
230 int irq;
231
232 /* CAN bus termination status */
233 struct completion termination_comp;
234 bool termination_enabled;
235
236 /* CAN bus error status registers */
237 struct completion buserror_comp;
238 struct can_berr_counter bec;
239
240 /* firmware type */
241 enum ican3_fwtype fwtype;
242 char fwinfo[32];
243
244 /* old and new style host interface */
245 unsigned int iftype;
246
247 /* queue for echo packets */
248 struct sk_buff_head echoq;
249
250 /*
251 * Any function which changes the current DPM page must hold this
252 * lock while it is performing data accesses. This ensures that the
253 * function will not be preempted and end up reading data from a
254 * different DPM page than it expects.
255 */
256 spinlock_t lock;
257
258 /* new host interface */
259 unsigned int rx_int;
260 unsigned int rx_num;
261 unsigned int tx_num;
262
263 /* fast host interface */
264 unsigned int fastrx_start;
265 unsigned int fastrx_num;
266 unsigned int fasttx_start;
267 unsigned int fasttx_num;
268
269 /* first free DPM page */
270 unsigned int free_page;
271};
272
273struct ican3_msg {
274 u8 control;
275 u8 spec;
276 __le16 len;
277 u8 data[252];
278};
279
280struct ican3_new_desc {
281 u8 control;
282 u8 pointer;
283};
284
285struct ican3_fast_desc {
286 u8 control;
287 u8 command;
288 u8 data[14];
289};
290
291/* write to the window basic address register */
292static inline void ican3_set_page(struct ican3_dev *mod, unsigned int page)
293{
294 BUG_ON(page >= DPM_NUM_PAGES);
295 iowrite8(page, &mod->dpmctrl->window_address);
296}
297
298/*
299 * ICAN3 "old-style" host interface
300 */
301
302/*
303 * Receive a message from the ICAN3 "old-style" firmware interface
304 *
305 * LOCKING: must hold mod->lock
306 *
307 * returns 0 on success, -ENOMEM when no message exists
308 */
309static int ican3_old_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
310{
311 unsigned int mbox, mbox_page;
312 u8 locl, peer, xord;
313
314 /* get the MSYNC registers */
315 ican3_set_page(mod, QUEUE_OLD_CONTROL);
316 peer = ioread8(mod->dpm + MSYNC_PEER);
317 locl = ioread8(mod->dpm + MSYNC_LOCL);
318 xord = locl ^ peer;
319
320 if ((xord & MSYNC_RB_MASK) == 0x00) {
321 netdev_dbg(mod->ndev, "no mbox for reading\n");
322 return -ENOMEM;
323 }
324
325 /* find the first free mbox to read */
326 if ((xord & MSYNC_RB_MASK) == MSYNC_RB_MASK)
327 mbox = (xord & MSYNC_RBLW) ? MSYNC_RB0 : MSYNC_RB1;
328 else
329 mbox = (xord & MSYNC_RB0) ? MSYNC_RB0 : MSYNC_RB1;
330
331 /* copy the message */
332 mbox_page = (mbox == MSYNC_RB0) ? QUEUE_OLD_RB0 : QUEUE_OLD_RB1;
333 ican3_set_page(mod, mbox_page);
334 memcpy_fromio(msg, mod->dpm, sizeof(*msg));
335
336 /*
337 * notify the firmware that the read buffer is available
338 * for it to fill again
339 */
340 locl ^= mbox;
341
342 ican3_set_page(mod, QUEUE_OLD_CONTROL);
343 iowrite8(locl, mod->dpm + MSYNC_LOCL);
344 return 0;
345}
346
347/*
348 * Send a message through the "old-style" firmware interface
349 *
350 * LOCKING: must hold mod->lock
351 *
352 * returns 0 on success, -ENOMEM when no free space exists
353 */
354static int ican3_old_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
355{
356 unsigned int mbox, mbox_page;
357 u8 locl, peer, xord;
358
359 /* get the MSYNC registers */
360 ican3_set_page(mod, QUEUE_OLD_CONTROL);
361 peer = ioread8(mod->dpm + MSYNC_PEER);
362 locl = ioread8(mod->dpm + MSYNC_LOCL);
363 xord = locl ^ peer;
364
365 if ((xord & MSYNC_WB_MASK) == MSYNC_WB_MASK) {
366 netdev_err(mod->ndev, "no mbox for writing\n");
367 return -ENOMEM;
368 }
369
370 /* calculate a free mbox to use */
371 mbox = (xord & MSYNC_WB0) ? MSYNC_WB1 : MSYNC_WB0;
372
373 /* copy the message to the DPM */
374 mbox_page = (mbox == MSYNC_WB0) ? QUEUE_OLD_WB0 : QUEUE_OLD_WB1;
375 ican3_set_page(mod, mbox_page);
376 memcpy_toio(mod->dpm, msg, sizeof(*msg));
377
378 locl ^= mbox;
379 if (mbox == MSYNC_WB1)
380 locl |= MSYNC_WBLW;
381
382 ican3_set_page(mod, QUEUE_OLD_CONTROL);
383 iowrite8(locl, mod->dpm + MSYNC_LOCL);
384 return 0;
385}
386
387/*
388 * ICAN3 "new-style" Host Interface Setup
389 */
390
391static void ican3_init_new_host_interface(struct ican3_dev *mod)
392{
393 struct ican3_new_desc desc;
394 unsigned long flags;
395 void __iomem *dst;
396 int i;
397
398 spin_lock_irqsave(&mod->lock, flags);
399
400 /* setup the internal datastructures for RX */
401 mod->rx_num = 0;
402 mod->rx_int = 0;
403
404 /* tohost queue descriptors are in page 5 */
405 ican3_set_page(mod, QUEUE_TOHOST);
406 dst = mod->dpm;
407
408 /* initialize the tohost (rx) queue descriptors: pages 9-24 */
409 for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
410 desc.control = DESC_INTERRUPT | DESC_LEN(1); /* I L=1 */
411 desc.pointer = mod->free_page;
412
413 /* set wrap flag on last buffer */
414 if (i == ICAN3_NEW_BUFFERS - 1)
415 desc.control |= DESC_WRAP;
416
417 memcpy_toio(dst, &desc, sizeof(desc));
418 dst += sizeof(desc);
419 mod->free_page++;
420 }
421
422 /* fromhost (tx) mid queue descriptors are in page 6 */
423 ican3_set_page(mod, QUEUE_FROMHOST_MID);
424 dst = mod->dpm;
425
426 /* setup the internal datastructures for TX */
427 mod->tx_num = 0;
428
429 /* initialize the fromhost mid queue descriptors: pages 25-40 */
430 for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
431 desc.control = DESC_VALID | DESC_LEN(1); /* V L=1 */
432 desc.pointer = mod->free_page;
433
434 /* set wrap flag on last buffer */
435 if (i == ICAN3_NEW_BUFFERS - 1)
436 desc.control |= DESC_WRAP;
437
438 memcpy_toio(dst, &desc, sizeof(desc));
439 dst += sizeof(desc);
440 mod->free_page++;
441 }
442
443 /* fromhost hi queue descriptors are in page 7 */
444 ican3_set_page(mod, QUEUE_FROMHOST_HIGH);
445 dst = mod->dpm;
446
447 /* initialize only a single buffer in the fromhost hi queue (unused) */
448 desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
449 desc.pointer = mod->free_page;
450 memcpy_toio(dst, &desc, sizeof(desc));
451 mod->free_page++;
452
453 /* fromhost low queue descriptors are in page 8 */
454 ican3_set_page(mod, QUEUE_FROMHOST_LOW);
455 dst = mod->dpm;
456
457 /* initialize only a single buffer in the fromhost low queue (unused) */
458 desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
459 desc.pointer = mod->free_page;
460 memcpy_toio(dst, &desc, sizeof(desc));
461 mod->free_page++;
462
463 spin_unlock_irqrestore(&mod->lock, flags);
464}
465
466/*
467 * ICAN3 Fast Host Interface Setup
468 */
469
470static void ican3_init_fast_host_interface(struct ican3_dev *mod)
471{
472 struct ican3_fast_desc desc;
473 unsigned long flags;
474 unsigned int addr;
475 void __iomem *dst;
476 int i;
477
478 spin_lock_irqsave(&mod->lock, flags);
479
480 /* save the start recv page */
481 mod->fastrx_start = mod->free_page;
482 mod->fastrx_num = 0;
483
484 /* build a single fast tohost queue descriptor */
485 memset(&desc, 0, sizeof(desc));
486 desc.control = 0x00;
487 desc.command = 1;
488
489 /* build the tohost queue descriptor ring in memory */
490 addr = 0;
491 for (i = 0; i < ICAN3_RX_BUFFERS; i++) {
492
493 /* set the wrap bit on the last buffer */
494 if (i == ICAN3_RX_BUFFERS - 1)
495 desc.control |= DESC_WRAP;
496
497 /* switch to the correct page */
498 ican3_set_page(mod, mod->free_page);
499
500 /* copy the descriptor to the DPM */
501 dst = mod->dpm + addr;
502 memcpy_toio(dst, &desc, sizeof(desc));
503 addr += sizeof(desc);
504
505 /* move to the next page if necessary */
506 if (addr >= DPM_PAGE_SIZE) {
507 addr = 0;
508 mod->free_page++;
509 }
510 }
511
512 /* make sure we page-align the next queue */
513 if (addr != 0)
514 mod->free_page++;
515
516 /* save the start xmit page */
517 mod->fasttx_start = mod->free_page;
518 mod->fasttx_num = 0;
519
520 /* build a single fast fromhost queue descriptor */
521 memset(&desc, 0, sizeof(desc));
522 desc.control = DESC_VALID;
523 desc.command = 1;
524
525 /* build the fromhost queue descriptor ring in memory */
526 addr = 0;
527 for (i = 0; i < ICAN3_TX_BUFFERS; i++) {
528
529 /* set the wrap bit on the last buffer */
530 if (i == ICAN3_TX_BUFFERS - 1)
531 desc.control |= DESC_WRAP;
532
533 /* switch to the correct page */
534 ican3_set_page(mod, mod->free_page);
535
536 /* copy the descriptor to the DPM */
537 dst = mod->dpm + addr;
538 memcpy_toio(dst, &desc, sizeof(desc));
539 addr += sizeof(desc);
540
541 /* move to the next page if necessary */
542 if (addr >= DPM_PAGE_SIZE) {
543 addr = 0;
544 mod->free_page++;
545 }
546 }
547
548 spin_unlock_irqrestore(&mod->lock, flags);
549}
550
551/*
552 * ICAN3 "new-style" Host Interface Message Helpers
553 */
554
555/*
556 * LOCKING: must hold mod->lock
557 */
558static int ican3_new_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
559{
560 struct ican3_new_desc desc;
561 void __iomem *desc_addr = mod->dpm + (mod->tx_num * sizeof(desc));
562
563 /* switch to the fromhost mid queue, and read the buffer descriptor */
564 ican3_set_page(mod, QUEUE_FROMHOST_MID);
565 memcpy_fromio(&desc, desc_addr, sizeof(desc));
566
567 if (!(desc.control & DESC_VALID)) {
568 netdev_dbg(mod->ndev, "%s: no free buffers\n", __func__);
569 return -ENOMEM;
570 }
571
572 /* switch to the data page, copy the data */
573 ican3_set_page(mod, desc.pointer);
574 memcpy_toio(mod->dpm, msg, sizeof(*msg));
575
576 /* switch back to the descriptor, set the valid bit, write it back */
577 ican3_set_page(mod, QUEUE_FROMHOST_MID);
578 desc.control ^= DESC_VALID;
579 memcpy_toio(desc_addr, &desc, sizeof(desc));
580
581 /* update the tx number */
582 mod->tx_num = (desc.control & DESC_WRAP) ? 0 : (mod->tx_num + 1);
583 return 0;
584}
585
586/*
587 * LOCKING: must hold mod->lock
588 */
589static int ican3_new_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
590{
591 struct ican3_new_desc desc;
592 void __iomem *desc_addr = mod->dpm + (mod->rx_num * sizeof(desc));
593
594 /* switch to the tohost queue, and read the buffer descriptor */
595 ican3_set_page(mod, QUEUE_TOHOST);
596 memcpy_fromio(&desc, desc_addr, sizeof(desc));
597
598 if (!(desc.control & DESC_VALID)) {
599 netdev_dbg(mod->ndev, "%s: no buffers to recv\n", __func__);
600 return -ENOMEM;
601 }
602
603 /* switch to the data page, copy the data */
604 ican3_set_page(mod, desc.pointer);
605 memcpy_fromio(msg, mod->dpm, sizeof(*msg));
606
607 /* switch back to the descriptor, toggle the valid bit, write it back */
608 ican3_set_page(mod, QUEUE_TOHOST);
609 desc.control ^= DESC_VALID;
610 memcpy_toio(desc_addr, &desc, sizeof(desc));
611
612 /* update the rx number */
613 mod->rx_num = (desc.control & DESC_WRAP) ? 0 : (mod->rx_num + 1);
614 return 0;
615}
616
617/*
618 * Message Send / Recv Helpers
619 */
620
621static int ican3_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
622{
623 unsigned long flags;
624 int ret;
625
626 spin_lock_irqsave(&mod->lock, flags);
627
628 if (mod->iftype == 0)
629 ret = ican3_old_send_msg(mod, msg);
630 else
631 ret = ican3_new_send_msg(mod, msg);
632
633 spin_unlock_irqrestore(&mod->lock, flags);
634 return ret;
635}
636
637static int ican3_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
638{
639 unsigned long flags;
640 int ret;
641
642 spin_lock_irqsave(&mod->lock, flags);
643
644 if (mod->iftype == 0)
645 ret = ican3_old_recv_msg(mod, msg);
646 else
647 ret = ican3_new_recv_msg(mod, msg);
648
649 spin_unlock_irqrestore(&mod->lock, flags);
650 return ret;
651}
652
653/*
654 * Quick Pre-constructed Messages
655 */
656
657static int ican3_msg_connect(struct ican3_dev *mod)
658{
659 struct ican3_msg msg;
660
661 memset(&msg, 0, sizeof(msg));
662 msg.spec = MSG_CONNECTI;
663 msg.len = cpu_to_le16(0);
664
665 return ican3_send_msg(mod, &msg);
666}
667
668static int ican3_msg_disconnect(struct ican3_dev *mod)
669{
670 struct ican3_msg msg;
671
672 memset(&msg, 0, sizeof(msg));
673 msg.spec = MSG_DISCONNECT;
674 msg.len = cpu_to_le16(0);
675
676 return ican3_send_msg(mod, &msg);
677}
678
679static int ican3_msg_newhostif(struct ican3_dev *mod)
680{
681 struct ican3_msg msg;
682 int ret;
683
684 memset(&msg, 0, sizeof(msg));
685 msg.spec = MSG_NEWHOSTIF;
686 msg.len = cpu_to_le16(0);
687
688 /* If we're not using the old interface, switching seems bogus */
689 WARN_ON(mod->iftype != 0);
690
691 ret = ican3_send_msg(mod, &msg);
692 if (ret)
693 return ret;
694
695 /* mark the module as using the new host interface */
696 mod->iftype = 1;
697 return 0;
698}
699
700static int ican3_msg_fasthostif(struct ican3_dev *mod)
701{
702 struct ican3_msg msg;
703 unsigned int addr;
704
705 memset(&msg, 0, sizeof(msg));
706 msg.spec = MSG_INITFDPMQUEUE;
707 msg.len = cpu_to_le16(8);
708
709 /* write the tohost queue start address */
710 addr = DPM_PAGE_ADDR(mod->fastrx_start);
711 msg.data[0] = addr & 0xff;
712 msg.data[1] = (addr >> 8) & 0xff;
713 msg.data[2] = (addr >> 16) & 0xff;
714 msg.data[3] = (addr >> 24) & 0xff;
715
716 /* write the fromhost queue start address */
717 addr = DPM_PAGE_ADDR(mod->fasttx_start);
718 msg.data[4] = addr & 0xff;
719 msg.data[5] = (addr >> 8) & 0xff;
720 msg.data[6] = (addr >> 16) & 0xff;
721 msg.data[7] = (addr >> 24) & 0xff;
722
723 /* If we're not using the new interface yet, we cannot do this */
724 WARN_ON(mod->iftype != 1);
725
726 return ican3_send_msg(mod, &msg);
727}
728
729/*
730 * Setup the CAN filter to either accept or reject all
731 * messages from the CAN bus.
732 */
733static int ican3_set_id_filter(struct ican3_dev *mod, bool accept)
734{
735 struct ican3_msg msg;
736 int ret;
737
738 /* Standard Frame Format */
739 memset(&msg, 0, sizeof(msg));
740 msg.spec = MSG_SETAFILMASK;
741 msg.len = cpu_to_le16(5);
742 msg.data[0] = 0x00; /* IDLo LSB */
743 msg.data[1] = 0x00; /* IDLo MSB */
744 msg.data[2] = 0xff; /* IDHi LSB */
745 msg.data[3] = 0x07; /* IDHi MSB */
746
747 /* accept all frames for fast host if, or reject all frames */
748 msg.data[4] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
749
750 ret = ican3_send_msg(mod, &msg);
751 if (ret)
752 return ret;
753
754 /* Extended Frame Format */
755 memset(&msg, 0, sizeof(msg));
756 msg.spec = MSG_SETAFILMASK;
757 msg.len = cpu_to_le16(13);
758 msg.data[0] = 0; /* MUX = 0 */
759 msg.data[1] = 0x00; /* IDLo LSB */
760 msg.data[2] = 0x00;
761 msg.data[3] = 0x00;
762 msg.data[4] = 0x20; /* IDLo MSB */
763 msg.data[5] = 0xff; /* IDHi LSB */
764 msg.data[6] = 0xff;
765 msg.data[7] = 0xff;
766 msg.data[8] = 0x3f; /* IDHi MSB */
767
768 /* accept all frames for fast host if, or reject all frames */
769 msg.data[9] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
770
771 return ican3_send_msg(mod, &msg);
772}
773
774/*
775 * Bring the CAN bus online or offline
776 */
777static int ican3_set_bus_state(struct ican3_dev *mod, bool on)
778{
779 struct can_bittiming *bt = &mod->can.bittiming;
780 struct ican3_msg msg;
781 u8 btr0, btr1;
782 int res;
783
784 /* This algorithm was stolen from drivers/net/can/sja1000/sja1000.c */
785 /* The bittiming register command for the ICAN3 just sets the bit timing */
786 /* registers on the SJA1000 chip directly */
787 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
788 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
789 (((bt->phase_seg2 - 1) & 0x7) << 4);
790 if (mod->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
791 btr1 |= 0x80;
792
793 if (mod->fwtype == ICAN3_FWTYPE_ICANOS) {
794 if (on) {
795 /* set bittiming */
796 memset(&msg, 0, sizeof(msg));
797 msg.spec = MSG_CBTRREQ;
798 msg.len = cpu_to_le16(4);
799 msg.data[0] = 0x00;
800 msg.data[1] = 0x00;
801 msg.data[2] = btr0;
802 msg.data[3] = btr1;
803
804 res = ican3_send_msg(mod, &msg);
805 if (res)
806 return res;
807 }
808
809 /* can-on/off request */
810 memset(&msg, 0, sizeof(msg));
811 msg.spec = on ? MSG_CONREQ : MSG_COFFREQ;
812 msg.len = cpu_to_le16(0);
813
814 return ican3_send_msg(mod, &msg);
815
816 } else if (mod->fwtype == ICAN3_FWTYPE_CAL_CANOPEN) {
817 /* bittiming + can-on/off request */
818 memset(&msg, 0, sizeof(msg));
819 msg.spec = MSG_LMTS;
820 if (on) {
821 msg.len = cpu_to_le16(4);
822 msg.data[0] = LMTS_BUSON_REQ;
823 msg.data[1] = 0;
824 msg.data[2] = btr0;
825 msg.data[3] = btr1;
826 } else {
827 msg.len = cpu_to_le16(2);
828 msg.data[0] = LMTS_BUSOFF_REQ;
829 msg.data[1] = 0;
830 }
831 res = ican3_send_msg(mod, &msg);
832 if (res)
833 return res;
834
835 if (on) {
836 /* create NMT Slave Node for error processing
837 * class 2 (with error capability, see CiA/DS203-1)
838 * id 1
839 * name locnod1 (must be exactly 7 bytes)
840 */
841 memset(&msg, 0, sizeof(msg));
842 msg.spec = MSG_NMTS;
843 msg.len = cpu_to_le16(11);
844 msg.data[0] = NMTS_CREATE_NODE_REQ;
845 msg.data[1] = 0;
846 msg.data[2] = 2; /* node class */
847 msg.data[3] = 1; /* node id */
848 strcpy(msg.data + 4, "locnod1"); /* node name */
849 return ican3_send_msg(mod, &msg);
850 }
851 return 0;
852 }
853 return -ENOTSUPP;
854}
855
856static int ican3_set_termination(struct ican3_dev *mod, bool on)
857{
858 struct ican3_msg msg;
859
860 memset(&msg, 0, sizeof(msg));
861 msg.spec = MSG_HWCONF;
862 msg.len = cpu_to_le16(2);
863 msg.data[0] = 0x00;
864 msg.data[1] = on ? HWCONF_TERMINATE_ON : HWCONF_TERMINATE_OFF;
865
866 return ican3_send_msg(mod, &msg);
867}
868
869static int ican3_send_inquiry(struct ican3_dev *mod, u8 subspec)
870{
871 struct ican3_msg msg;
872
873 memset(&msg, 0, sizeof(msg));
874 msg.spec = MSG_INQUIRY;
875 msg.len = cpu_to_le16(2);
876 msg.data[0] = subspec;
877 msg.data[1] = 0x00;
878
879 return ican3_send_msg(mod, &msg);
880}
881
882static int ican3_set_buserror(struct ican3_dev *mod, u8 quota)
883{
884 struct ican3_msg msg;
885
886 if (mod->fwtype == ICAN3_FWTYPE_ICANOS) {
887 memset(&msg, 0, sizeof(msg));
888 msg.spec = MSG_CCONFREQ;
889 msg.len = cpu_to_le16(2);
890 msg.data[0] = 0x00;
891 msg.data[1] = quota;
892 } else if (mod->fwtype == ICAN3_FWTYPE_CAL_CANOPEN) {
893 memset(&msg, 0, sizeof(msg));
894 msg.spec = MSG_LMTS;
895 msg.len = cpu_to_le16(4);
896 msg.data[0] = LMTS_CAN_CONF_REQ;
897 msg.data[1] = 0x00;
898 msg.data[2] = 0x00;
899 msg.data[3] = quota;
900 } else {
901 return -ENOTSUPP;
902 }
903 return ican3_send_msg(mod, &msg);
904}
905
906/*
907 * ICAN3 to Linux CAN Frame Conversion
908 */
909
910static void ican3_to_can_frame(struct ican3_dev *mod,
911 struct ican3_fast_desc *desc,
912 struct can_frame *cf)
913{
914 if ((desc->command & ICAN3_CAN_TYPE_MASK) == ICAN3_CAN_TYPE_SFF) {
915 if (desc->data[1] & ICAN3_SFF_RTR)
916 cf->can_id |= CAN_RTR_FLAG;
917
918 cf->can_id |= desc->data[0] << 3;
919 cf->can_id |= (desc->data[1] & 0xe0) >> 5;
920 cf->len = can_cc_dlc2len(desc->data[1] & ICAN3_CAN_DLC_MASK);
921 memcpy(cf->data, &desc->data[2], cf->len);
922 } else {
923 cf->len = can_cc_dlc2len(desc->data[0] & ICAN3_CAN_DLC_MASK);
924 if (desc->data[0] & ICAN3_EFF_RTR)
925 cf->can_id |= CAN_RTR_FLAG;
926
927 if (desc->data[0] & ICAN3_EFF) {
928 cf->can_id |= CAN_EFF_FLAG;
929 cf->can_id |= desc->data[2] << 21; /* 28-21 */
930 cf->can_id |= desc->data[3] << 13; /* 20-13 */
931 cf->can_id |= desc->data[4] << 5; /* 12-5 */
932 cf->can_id |= (desc->data[5] & 0xf8) >> 3;
933 } else {
934 cf->can_id |= desc->data[2] << 3; /* 10-3 */
935 cf->can_id |= desc->data[3] >> 5; /* 2-0 */
936 }
937
938 memcpy(cf->data, &desc->data[6], cf->len);
939 }
940}
941
942static void can_frame_to_ican3(struct ican3_dev *mod,
943 struct can_frame *cf,
944 struct ican3_fast_desc *desc)
945{
946 /* clear out any stale data in the descriptor */
947 memset(desc->data, 0, sizeof(desc->data));
948
949 /* we always use the extended format, with the ECHO flag set */
950 desc->command = ICAN3_CAN_TYPE_EFF;
951 desc->data[0] |= cf->len;
952 desc->data[1] |= ICAN3_ECHO;
953
954 /* support single transmission (no retries) mode */
955 if (mod->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
956 desc->data[1] |= ICAN3_SNGL;
957
958 if (cf->can_id & CAN_RTR_FLAG)
959 desc->data[0] |= ICAN3_EFF_RTR;
960
961 /* pack the id into the correct places */
962 if (cf->can_id & CAN_EFF_FLAG) {
963 desc->data[0] |= ICAN3_EFF;
964 desc->data[2] = (cf->can_id & 0x1fe00000) >> 21; /* 28-21 */
965 desc->data[3] = (cf->can_id & 0x001fe000) >> 13; /* 20-13 */
966 desc->data[4] = (cf->can_id & 0x00001fe0) >> 5; /* 12-5 */
967 desc->data[5] = (cf->can_id & 0x0000001f) << 3; /* 4-0 */
968 } else {
969 desc->data[2] = (cf->can_id & 0x7F8) >> 3; /* bits 10-3 */
970 desc->data[3] = (cf->can_id & 0x007) << 5; /* bits 2-0 */
971 }
972
973 /* copy the data bits into the descriptor */
974 memcpy(&desc->data[6], cf->data, cf->len);
975}
976
977/*
978 * Interrupt Handling
979 */
980
981/*
982 * Handle an ID + Version message response from the firmware. We never generate
983 * this message in production code, but it is very useful when debugging to be
984 * able to display this message.
985 */
986static void ican3_handle_idvers(struct ican3_dev *mod, struct ican3_msg *msg)
987{
988 netdev_dbg(mod->ndev, "IDVERS response: %s\n", msg->data);
989}
990
991static void ican3_handle_msglost(struct ican3_dev *mod, struct ican3_msg *msg)
992{
993 struct net_device *dev = mod->ndev;
994 struct net_device_stats *stats = &dev->stats;
995 struct can_frame *cf;
996 struct sk_buff *skb;
997
998 /*
999 * Report that communication messages with the microcontroller firmware
1000 * are being lost. These are never CAN frames, so we do not generate an
1001 * error frame for userspace
1002 */
1003 if (msg->spec == MSG_MSGLOST) {
1004 netdev_err(mod->ndev, "lost %d control messages\n", msg->data[0]);
1005 return;
1006 }
1007
1008 /*
1009 * Oops, this indicates that we have lost messages in the fast queue,
1010 * which are exclusively CAN messages. Our driver isn't reading CAN
1011 * frames fast enough.
1012 *
1013 * We'll pretend that the SJA1000 told us that it ran out of buffer
1014 * space, because there is not a better message for this.
1015 */
1016 skb = alloc_can_err_skb(dev, &cf);
1017 if (skb) {
1018 cf->can_id |= CAN_ERR_CRTL;
1019 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
1020 stats->rx_over_errors++;
1021 stats->rx_errors++;
1022 netif_rx(skb);
1023 }
1024}
1025
1026/*
1027 * Handle CAN Event Indication Messages from the firmware
1028 *
1029 * The ICAN3 firmware provides the values of some SJA1000 registers when it
1030 * generates this message. The code below is largely copied from the
1031 * drivers/net/can/sja1000/sja1000.c file, and adapted as necessary
1032 */
1033static int ican3_handle_cevtind(struct ican3_dev *mod, struct ican3_msg *msg)
1034{
1035 struct net_device *dev = mod->ndev;
1036 struct net_device_stats *stats = &dev->stats;
1037 enum can_state state = mod->can.state;
1038 u8 isrc, ecc, status, rxerr, txerr;
1039 struct can_frame *cf;
1040 struct sk_buff *skb;
1041
1042 /* we can only handle the SJA1000 part */
1043 if (msg->data[1] != CEVTIND_CHIP_SJA1000) {
1044 netdev_err(mod->ndev, "unable to handle errors on non-SJA1000\n");
1045 return -ENODEV;
1046 }
1047
1048 /* check the message length for sanity */
1049 if (le16_to_cpu(msg->len) < 6) {
1050 netdev_err(mod->ndev, "error message too short\n");
1051 return -EINVAL;
1052 }
1053
1054 isrc = msg->data[0];
1055 ecc = msg->data[2];
1056 status = msg->data[3];
1057 rxerr = msg->data[4];
1058 txerr = msg->data[5];
1059
1060 /*
1061 * This hardware lacks any support other than bus error messages to
1062 * determine if packet transmission has failed.
1063 *
1064 * When TX errors happen, one echo skb needs to be dropped from the
1065 * front of the queue.
1066 *
1067 * A small bit of code is duplicated here and below, to avoid error
1068 * skb allocation when it will just be freed immediately.
1069 */
1070 if (isrc == CEVTIND_BEI) {
1071 int ret;
1072 netdev_dbg(mod->ndev, "bus error interrupt\n");
1073
1074 /* TX error */
1075 if (!(ecc & ECC_DIR)) {
1076 kfree_skb(skb_dequeue(&mod->echoq));
1077 stats->tx_errors++;
1078 } else {
1079 stats->rx_errors++;
1080 }
1081
1082 /*
1083 * The controller automatically disables bus-error interrupts
1084 * and therefore we must re-enable them.
1085 */
1086 ret = ican3_set_buserror(mod, 1);
1087 if (ret) {
1088 netdev_err(mod->ndev, "unable to re-enable bus-error\n");
1089 return ret;
1090 }
1091
1092 /* bus error reporting is off, return immediately */
1093 if (!(mod->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1094 return 0;
1095 }
1096
1097 skb = alloc_can_err_skb(dev, &cf);
1098 if (skb == NULL)
1099 return -ENOMEM;
1100
1101 /* data overrun interrupt */
1102 if (isrc == CEVTIND_DOI || isrc == CEVTIND_LOST) {
1103 netdev_dbg(mod->ndev, "data overrun interrupt\n");
1104 cf->can_id |= CAN_ERR_CRTL;
1105 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
1106 stats->rx_over_errors++;
1107 stats->rx_errors++;
1108 }
1109
1110 /* error warning + passive interrupt */
1111 if (isrc == CEVTIND_EI) {
1112 netdev_dbg(mod->ndev, "error warning + passive interrupt\n");
1113 if (status & SR_BS) {
1114 state = CAN_STATE_BUS_OFF;
1115 cf->can_id |= CAN_ERR_BUSOFF;
1116 mod->can.can_stats.bus_off++;
1117 can_bus_off(dev);
1118 } else if (status & SR_ES) {
1119 if (rxerr >= 128 || txerr >= 128)
1120 state = CAN_STATE_ERROR_PASSIVE;
1121 else
1122 state = CAN_STATE_ERROR_WARNING;
1123 } else {
1124 state = CAN_STATE_ERROR_ACTIVE;
1125 }
1126 }
1127
1128 /* bus error interrupt */
1129 if (isrc == CEVTIND_BEI) {
1130 mod->can.can_stats.bus_error++;
1131 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR | CAN_ERR_CNT;
1132
1133 switch (ecc & ECC_MASK) {
1134 case ECC_BIT:
1135 cf->data[2] |= CAN_ERR_PROT_BIT;
1136 break;
1137 case ECC_FORM:
1138 cf->data[2] |= CAN_ERR_PROT_FORM;
1139 break;
1140 case ECC_STUFF:
1141 cf->data[2] |= CAN_ERR_PROT_STUFF;
1142 break;
1143 default:
1144 cf->data[3] = ecc & ECC_SEG;
1145 break;
1146 }
1147
1148 if (!(ecc & ECC_DIR))
1149 cf->data[2] |= CAN_ERR_PROT_TX;
1150
1151 cf->data[6] = txerr;
1152 cf->data[7] = rxerr;
1153 }
1154
1155 if (state != mod->can.state && (state == CAN_STATE_ERROR_WARNING ||
1156 state == CAN_STATE_ERROR_PASSIVE)) {
1157 cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
1158 if (state == CAN_STATE_ERROR_WARNING) {
1159 mod->can.can_stats.error_warning++;
1160 cf->data[1] = (txerr > rxerr) ?
1161 CAN_ERR_CRTL_TX_WARNING :
1162 CAN_ERR_CRTL_RX_WARNING;
1163 } else {
1164 mod->can.can_stats.error_passive++;
1165 cf->data[1] = (txerr > rxerr) ?
1166 CAN_ERR_CRTL_TX_PASSIVE :
1167 CAN_ERR_CRTL_RX_PASSIVE;
1168 }
1169
1170 cf->data[6] = txerr;
1171 cf->data[7] = rxerr;
1172 }
1173
1174 mod->can.state = state;
1175 netif_rx(skb);
1176 return 0;
1177}
1178
1179static void ican3_handle_inquiry(struct ican3_dev *mod, struct ican3_msg *msg)
1180{
1181 switch (msg->data[0]) {
1182 case INQUIRY_STATUS:
1183 case INQUIRY_EXTENDED:
1184 mod->bec.rxerr = msg->data[5];
1185 mod->bec.txerr = msg->data[6];
1186 complete(&mod->buserror_comp);
1187 break;
1188 case INQUIRY_TERMINATION:
1189 mod->termination_enabled = msg->data[6] & HWCONF_TERMINATE_ON;
1190 complete(&mod->termination_comp);
1191 break;
1192 default:
1193 netdev_err(mod->ndev, "received an unknown inquiry response\n");
1194 break;
1195 }
1196}
1197
1198/* Handle NMTS Slave Event Indication Messages from the firmware */
1199static void ican3_handle_nmtsind(struct ican3_dev *mod, struct ican3_msg *msg)
1200{
1201 u16 subspec;
1202
1203 subspec = msg->data[0] + msg->data[1] * 0x100;
1204 if (subspec == NMTS_SLAVE_EVENT_IND) {
1205 switch (msg->data[2]) {
1206 case NE_LOCAL_OCCURRED:
1207 case NE_LOCAL_RESOLVED:
1208 /* now follows the same message as Raw ICANOS CEVTIND
1209 * shift the data at the same place and call this method
1210 */
1211 le16_add_cpu(&msg->len, -3);
1212 memmove(msg->data, msg->data + 3, le16_to_cpu(msg->len));
1213 ican3_handle_cevtind(mod, msg);
1214 break;
1215 case NE_REMOTE_OCCURRED:
1216 case NE_REMOTE_RESOLVED:
1217 /* should not occurre, ignore */
1218 break;
1219 default:
1220 netdev_warn(mod->ndev, "unknown NMTS event indication %x\n",
1221 msg->data[2]);
1222 break;
1223 }
1224 } else if (subspec == NMTS_SLAVE_STATE_IND) {
1225 /* ignore state indications */
1226 } else {
1227 netdev_warn(mod->ndev, "unhandled NMTS indication %x\n",
1228 subspec);
1229 return;
1230 }
1231}
1232
1233static void ican3_handle_unknown_message(struct ican3_dev *mod,
1234 struct ican3_msg *msg)
1235{
1236 netdev_warn(mod->ndev, "received unknown message: spec 0x%.2x length %d\n",
1237 msg->spec, le16_to_cpu(msg->len));
1238}
1239
1240/*
1241 * Handle a control message from the firmware
1242 */
1243static void ican3_handle_message(struct ican3_dev *mod, struct ican3_msg *msg)
1244{
1245 netdev_dbg(mod->ndev, "%s: modno %d spec 0x%.2x len %d bytes\n", __func__,
1246 mod->num, msg->spec, le16_to_cpu(msg->len));
1247
1248 switch (msg->spec) {
1249 case MSG_IDVERS:
1250 ican3_handle_idvers(mod, msg);
1251 break;
1252 case MSG_MSGLOST:
1253 case MSG_FMSGLOST:
1254 ican3_handle_msglost(mod, msg);
1255 break;
1256 case MSG_CEVTIND:
1257 ican3_handle_cevtind(mod, msg);
1258 break;
1259 case MSG_INQUIRY:
1260 ican3_handle_inquiry(mod, msg);
1261 break;
1262 case MSG_NMTS:
1263 ican3_handle_nmtsind(mod, msg);
1264 break;
1265 default:
1266 ican3_handle_unknown_message(mod, msg);
1267 break;
1268 }
1269}
1270
1271/*
1272 * The ican3 needs to store all echo skbs, and therefore cannot
1273 * use the generic infrastructure for this.
1274 */
1275static void ican3_put_echo_skb(struct ican3_dev *mod, struct sk_buff *skb)
1276{
1277 skb = can_create_echo_skb(skb);
1278 if (!skb)
1279 return;
1280
1281 skb_tx_timestamp(skb);
1282
1283 /* save this skb for tx interrupt echo handling */
1284 skb_queue_tail(&mod->echoq, skb);
1285}
1286
1287static unsigned int ican3_get_echo_skb(struct ican3_dev *mod)
1288{
1289 struct sk_buff *skb = skb_dequeue(&mod->echoq);
1290 struct can_frame *cf;
1291 u8 dlc = 0;
1292
1293 /* this should never trigger unless there is a driver bug */
1294 if (!skb) {
1295 netdev_err(mod->ndev, "BUG: echo skb not occupied\n");
1296 return 0;
1297 }
1298
1299 cf = (struct can_frame *)skb->data;
1300 if (!(cf->can_id & CAN_RTR_FLAG))
1301 dlc = cf->len;
1302
1303 /* check flag whether this packet has to be looped back */
1304 if (skb->pkt_type != PACKET_LOOPBACK) {
1305 kfree_skb(skb);
1306 return dlc;
1307 }
1308
1309 skb->protocol = htons(ETH_P_CAN);
1310 skb->pkt_type = PACKET_BROADCAST;
1311 skb->ip_summed = CHECKSUM_UNNECESSARY;
1312 skb->dev = mod->ndev;
1313 netif_receive_skb(skb);
1314 return dlc;
1315}
1316
1317/*
1318 * Compare an skb with an existing echo skb
1319 *
1320 * This function will be used on devices which have a hardware loopback.
1321 * On these devices, this function can be used to compare a received skb
1322 * with the saved echo skbs so that the hardware echo skb can be dropped.
1323 *
1324 * Returns true if the skb's are identical, false otherwise.
1325 */
1326static bool ican3_echo_skb_matches(struct ican3_dev *mod, struct sk_buff *skb)
1327{
1328 struct can_frame *cf = (struct can_frame *)skb->data;
1329 struct sk_buff *echo_skb = skb_peek(&mod->echoq);
1330 struct can_frame *echo_cf;
1331
1332 if (!echo_skb)
1333 return false;
1334
1335 echo_cf = (struct can_frame *)echo_skb->data;
1336 if (cf->can_id != echo_cf->can_id)
1337 return false;
1338
1339 if (cf->len != echo_cf->len)
1340 return false;
1341
1342 return memcmp(cf->data, echo_cf->data, cf->len) == 0;
1343}
1344
1345/*
1346 * Check that there is room in the TX ring to transmit another skb
1347 *
1348 * LOCKING: must hold mod->lock
1349 */
1350static bool ican3_txok(struct ican3_dev *mod)
1351{
1352 struct ican3_fast_desc __iomem *desc;
1353 u8 control;
1354
1355 /* check that we have echo queue space */
1356 if (skb_queue_len(&mod->echoq) >= ICAN3_TX_BUFFERS)
1357 return false;
1358
1359 /* copy the control bits of the descriptor */
1360 ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
1361 desc = mod->dpm + ((mod->fasttx_num % 16) * sizeof(*desc));
1362 control = ioread8(&desc->control);
1363
1364 /* if the control bits are not valid, then we have no more space */
1365 if (!(control & DESC_VALID))
1366 return false;
1367
1368 return true;
1369}
1370
1371/*
1372 * Receive one CAN frame from the hardware
1373 *
1374 * CONTEXT: must be called from user context
1375 */
1376static int ican3_recv_skb(struct ican3_dev *mod)
1377{
1378 struct net_device *ndev = mod->ndev;
1379 struct net_device_stats *stats = &ndev->stats;
1380 struct ican3_fast_desc desc;
1381 void __iomem *desc_addr;
1382 struct can_frame *cf;
1383 struct sk_buff *skb;
1384 unsigned long flags;
1385
1386 spin_lock_irqsave(&mod->lock, flags);
1387
1388 /* copy the whole descriptor */
1389 ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
1390 desc_addr = mod->dpm + ((mod->fastrx_num % 16) * sizeof(desc));
1391 memcpy_fromio(&desc, desc_addr, sizeof(desc));
1392
1393 spin_unlock_irqrestore(&mod->lock, flags);
1394
1395 /* check that we actually have a CAN frame */
1396 if (!(desc.control & DESC_VALID))
1397 return -ENOBUFS;
1398
1399 /* allocate an skb */
1400 skb = alloc_can_skb(ndev, &cf);
1401 if (unlikely(skb == NULL)) {
1402 stats->rx_dropped++;
1403 goto err_noalloc;
1404 }
1405
1406 /* convert the ICAN3 frame into Linux CAN format */
1407 ican3_to_can_frame(mod, &desc, cf);
1408
1409 /*
1410 * If this is an ECHO frame received from the hardware loopback
1411 * feature, use the skb saved in the ECHO stack instead. This allows
1412 * the Linux CAN core to support CAN_RAW_RECV_OWN_MSGS correctly.
1413 *
1414 * Since this is a confirmation of a successfully transmitted packet
1415 * sent from this host, update the transmit statistics.
1416 *
1417 * Also, the netdevice queue needs to be allowed to send packets again.
1418 */
1419 if (ican3_echo_skb_matches(mod, skb)) {
1420 stats->tx_packets++;
1421 stats->tx_bytes += ican3_get_echo_skb(mod);
1422 kfree_skb(skb);
1423 goto err_noalloc;
1424 }
1425
1426 /* update statistics, receive the skb */
1427 stats->rx_packets++;
1428 if (!(cf->can_id & CAN_RTR_FLAG))
1429 stats->rx_bytes += cf->len;
1430 netif_receive_skb(skb);
1431
1432err_noalloc:
1433 /* toggle the valid bit and return the descriptor to the ring */
1434 desc.control ^= DESC_VALID;
1435
1436 spin_lock_irqsave(&mod->lock, flags);
1437
1438 ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
1439 memcpy_toio(desc_addr, &desc, 1);
1440
1441 /* update the next buffer pointer */
1442 mod->fastrx_num = (desc.control & DESC_WRAP) ? 0
1443 : (mod->fastrx_num + 1);
1444
1445 /* there are still more buffers to process */
1446 spin_unlock_irqrestore(&mod->lock, flags);
1447 return 0;
1448}
1449
1450static int ican3_napi(struct napi_struct *napi, int budget)
1451{
1452 struct ican3_dev *mod = container_of(napi, struct ican3_dev, napi);
1453 unsigned long flags;
1454 int received = 0;
1455 int ret;
1456
1457 /* process all communication messages */
1458 while (true) {
1459 struct ican3_msg msg;
1460 ret = ican3_recv_msg(mod, &msg);
1461 if (ret)
1462 break;
1463
1464 ican3_handle_message(mod, &msg);
1465 }
1466
1467 /* process all CAN frames from the fast interface */
1468 while (received < budget) {
1469 ret = ican3_recv_skb(mod);
1470 if (ret)
1471 break;
1472
1473 received++;
1474 }
1475
1476 /* We have processed all packets that the adapter had, but it
1477 * was less than our budget, stop polling */
1478 if (received < budget)
1479 napi_complete_done(napi, received);
1480
1481 spin_lock_irqsave(&mod->lock, flags);
1482
1483 /* Wake up the transmit queue if necessary */
1484 if (netif_queue_stopped(mod->ndev) && ican3_txok(mod))
1485 netif_wake_queue(mod->ndev);
1486
1487 spin_unlock_irqrestore(&mod->lock, flags);
1488
1489 /* re-enable interrupt generation */
1490 iowrite8(1 << mod->num, &mod->ctrl->int_enable);
1491 return received;
1492}
1493
1494static irqreturn_t ican3_irq(int irq, void *dev_id)
1495{
1496 struct ican3_dev *mod = dev_id;
1497 u8 stat;
1498
1499 /*
1500 * The interrupt status register on this device reports interrupts
1501 * as zeroes instead of using ones like most other devices
1502 */
1503 stat = ioread8(&mod->ctrl->int_disable) & (1 << mod->num);
1504 if (stat == (1 << mod->num))
1505 return IRQ_NONE;
1506
1507 /* clear the MODULbus interrupt from the microcontroller */
1508 ioread8(&mod->dpmctrl->interrupt);
1509
1510 /* disable interrupt generation, schedule the NAPI poller */
1511 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
1512 napi_schedule(&mod->napi);
1513 return IRQ_HANDLED;
1514}
1515
1516/*
1517 * Firmware reset, startup, and shutdown
1518 */
1519
1520/*
1521 * Reset an ICAN module to its power-on state
1522 *
1523 * CONTEXT: no network device registered
1524 */
1525static int ican3_reset_module(struct ican3_dev *mod)
1526{
1527 unsigned long start;
1528 u8 runold, runnew;
1529
1530 /* disable interrupts so no more work is scheduled */
1531 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
1532
1533 /* the first unallocated page in the DPM is #9 */
1534 mod->free_page = DPM_FREE_START;
1535
1536 ican3_set_page(mod, QUEUE_OLD_CONTROL);
1537 runold = ioread8(mod->dpm + TARGET_RUNNING);
1538
1539 /* reset the module */
1540 iowrite8(0x00, &mod->dpmctrl->hwreset);
1541
1542 /* wait until the module has finished resetting and is running */
1543 start = jiffies;
1544 do {
1545 ican3_set_page(mod, QUEUE_OLD_CONTROL);
1546 runnew = ioread8(mod->dpm + TARGET_RUNNING);
1547 if (runnew == (runold ^ 0xff))
1548 return 0;
1549
1550 msleep(10);
1551 } while (time_before(jiffies, start + HZ / 2));
1552
1553 netdev_err(mod->ndev, "failed to reset CAN module\n");
1554 return -ETIMEDOUT;
1555}
1556
1557static void ican3_shutdown_module(struct ican3_dev *mod)
1558{
1559 ican3_msg_disconnect(mod);
1560 ican3_reset_module(mod);
1561}
1562
1563/*
1564 * Startup an ICAN module, bringing it into fast mode
1565 */
1566static int ican3_startup_module(struct ican3_dev *mod)
1567{
1568 int ret;
1569
1570 ret = ican3_reset_module(mod);
1571 if (ret) {
1572 netdev_err(mod->ndev, "unable to reset module\n");
1573 return ret;
1574 }
1575
1576 /* detect firmware */
1577 memcpy_fromio(mod->fwinfo, mod->dpm + FIRMWARE_STAMP, sizeof(mod->fwinfo) - 1);
1578 if (strncmp(mod->fwinfo, "JANZ-ICAN3", 10)) {
1579 netdev_err(mod->ndev, "ICAN3 not detected (found %s)\n", mod->fwinfo);
1580 return -ENODEV;
1581 }
1582 if (strstr(mod->fwinfo, "CAL/CANopen"))
1583 mod->fwtype = ICAN3_FWTYPE_CAL_CANOPEN;
1584 else
1585 mod->fwtype = ICAN3_FWTYPE_ICANOS;
1586
1587 /* re-enable interrupts so we can send messages */
1588 iowrite8(1 << mod->num, &mod->ctrl->int_enable);
1589
1590 ret = ican3_msg_connect(mod);
1591 if (ret) {
1592 netdev_err(mod->ndev, "unable to connect to module\n");
1593 return ret;
1594 }
1595
1596 ican3_init_new_host_interface(mod);
1597 ret = ican3_msg_newhostif(mod);
1598 if (ret) {
1599 netdev_err(mod->ndev, "unable to switch to new-style interface\n");
1600 return ret;
1601 }
1602
1603 /* default to "termination on" */
1604 ret = ican3_set_termination(mod, true);
1605 if (ret) {
1606 netdev_err(mod->ndev, "unable to enable termination\n");
1607 return ret;
1608 }
1609
1610 /* default to "bus errors enabled" */
1611 ret = ican3_set_buserror(mod, 1);
1612 if (ret) {
1613 netdev_err(mod->ndev, "unable to set bus-error\n");
1614 return ret;
1615 }
1616
1617 ican3_init_fast_host_interface(mod);
1618 ret = ican3_msg_fasthostif(mod);
1619 if (ret) {
1620 netdev_err(mod->ndev, "unable to switch to fast host interface\n");
1621 return ret;
1622 }
1623
1624 ret = ican3_set_id_filter(mod, true);
1625 if (ret) {
1626 netdev_err(mod->ndev, "unable to set acceptance filter\n");
1627 return ret;
1628 }
1629
1630 return 0;
1631}
1632
1633/*
1634 * CAN Network Device
1635 */
1636
1637static int ican3_open(struct net_device *ndev)
1638{
1639 struct ican3_dev *mod = netdev_priv(ndev);
1640 int ret;
1641
1642 /* open the CAN layer */
1643 ret = open_candev(ndev);
1644 if (ret) {
1645 netdev_err(mod->ndev, "unable to start CAN layer\n");
1646 return ret;
1647 }
1648
1649 /* bring the bus online */
1650 ret = ican3_set_bus_state(mod, true);
1651 if (ret) {
1652 netdev_err(mod->ndev, "unable to set bus-on\n");
1653 close_candev(ndev);
1654 return ret;
1655 }
1656
1657 /* start up the network device */
1658 mod->can.state = CAN_STATE_ERROR_ACTIVE;
1659 netif_start_queue(ndev);
1660
1661 return 0;
1662}
1663
1664static int ican3_stop(struct net_device *ndev)
1665{
1666 struct ican3_dev *mod = netdev_priv(ndev);
1667 int ret;
1668
1669 /* stop the network device xmit routine */
1670 netif_stop_queue(ndev);
1671 mod->can.state = CAN_STATE_STOPPED;
1672
1673 /* bring the bus offline, stop receiving packets */
1674 ret = ican3_set_bus_state(mod, false);
1675 if (ret) {
1676 netdev_err(mod->ndev, "unable to set bus-off\n");
1677 return ret;
1678 }
1679
1680 /* drop all outstanding echo skbs */
1681 skb_queue_purge(&mod->echoq);
1682
1683 /* close the CAN layer */
1684 close_candev(ndev);
1685 return 0;
1686}
1687
1688static netdev_tx_t ican3_xmit(struct sk_buff *skb, struct net_device *ndev)
1689{
1690 struct ican3_dev *mod = netdev_priv(ndev);
1691 struct can_frame *cf = (struct can_frame *)skb->data;
1692 struct ican3_fast_desc desc;
1693 void __iomem *desc_addr;
1694 unsigned long flags;
1695
1696 if (can_dev_dropped_skb(ndev, skb))
1697 return NETDEV_TX_OK;
1698
1699 spin_lock_irqsave(&mod->lock, flags);
1700
1701 /* check that we can actually transmit */
1702 if (!ican3_txok(mod)) {
1703 netdev_err(mod->ndev, "BUG: no free descriptors\n");
1704 spin_unlock_irqrestore(&mod->lock, flags);
1705 return NETDEV_TX_BUSY;
1706 }
1707
1708 /* copy the control bits of the descriptor */
1709 ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
1710 desc_addr = mod->dpm + ((mod->fasttx_num % 16) * sizeof(desc));
1711 memset(&desc, 0, sizeof(desc));
1712 memcpy_fromio(&desc, desc_addr, 1);
1713
1714 /* convert the Linux CAN frame into ICAN3 format */
1715 can_frame_to_ican3(mod, cf, &desc);
1716
1717 /*
1718 * This hardware doesn't have TX-done notifications, so we'll try and
1719 * emulate it the best we can using ECHO skbs. Add the skb to the ECHO
1720 * stack. Upon packet reception, check if the ECHO skb and received
1721 * skb match, and use that to wake the queue.
1722 */
1723 ican3_put_echo_skb(mod, skb);
1724
1725 /*
1726 * the programming manual says that you must set the IVALID bit, then
1727 * interrupt, then set the valid bit. Quite weird, but it seems to be
1728 * required for this to work
1729 */
1730 desc.control |= DESC_IVALID;
1731 memcpy_toio(desc_addr, &desc, sizeof(desc));
1732
1733 /* generate a MODULbus interrupt to the microcontroller */
1734 iowrite8(0x01, &mod->dpmctrl->interrupt);
1735
1736 desc.control ^= DESC_VALID;
1737 memcpy_toio(desc_addr, &desc, sizeof(desc));
1738
1739 /* update the next buffer pointer */
1740 mod->fasttx_num = (desc.control & DESC_WRAP) ? 0
1741 : (mod->fasttx_num + 1);
1742
1743 /* if there is no free descriptor space, stop the transmit queue */
1744 if (!ican3_txok(mod))
1745 netif_stop_queue(ndev);
1746
1747 spin_unlock_irqrestore(&mod->lock, flags);
1748 return NETDEV_TX_OK;
1749}
1750
1751static const struct net_device_ops ican3_netdev_ops = {
1752 .ndo_open = ican3_open,
1753 .ndo_stop = ican3_stop,
1754 .ndo_start_xmit = ican3_xmit,
1755 .ndo_change_mtu = can_change_mtu,
1756};
1757
1758static const struct ethtool_ops ican3_ethtool_ops = {
1759 .get_ts_info = ethtool_op_get_ts_info,
1760};
1761
1762/*
1763 * Low-level CAN Device
1764 */
1765
1766/* This structure was stolen from drivers/net/can/sja1000/sja1000.c */
1767static const struct can_bittiming_const ican3_bittiming_const = {
1768 .name = DRV_NAME,
1769 .tseg1_min = 1,
1770 .tseg1_max = 16,
1771 .tseg2_min = 1,
1772 .tseg2_max = 8,
1773 .sjw_max = 4,
1774 .brp_min = 1,
1775 .brp_max = 64,
1776 .brp_inc = 1,
1777};
1778
1779static int ican3_set_mode(struct net_device *ndev, enum can_mode mode)
1780{
1781 struct ican3_dev *mod = netdev_priv(ndev);
1782 int ret;
1783
1784 if (mode != CAN_MODE_START)
1785 return -ENOTSUPP;
1786
1787 /* bring the bus online */
1788 ret = ican3_set_bus_state(mod, true);
1789 if (ret) {
1790 netdev_err(ndev, "unable to set bus-on\n");
1791 return ret;
1792 }
1793
1794 /* start up the network device */
1795 mod->can.state = CAN_STATE_ERROR_ACTIVE;
1796
1797 if (netif_queue_stopped(ndev))
1798 netif_wake_queue(ndev);
1799
1800 return 0;
1801}
1802
1803static int ican3_get_berr_counter(const struct net_device *ndev,
1804 struct can_berr_counter *bec)
1805{
1806 struct ican3_dev *mod = netdev_priv(ndev);
1807 int ret;
1808
1809 ret = ican3_send_inquiry(mod, INQUIRY_STATUS);
1810 if (ret)
1811 return ret;
1812
1813 if (!wait_for_completion_timeout(&mod->buserror_comp, HZ)) {
1814 netdev_info(mod->ndev, "%s timed out\n", __func__);
1815 return -ETIMEDOUT;
1816 }
1817
1818 bec->rxerr = mod->bec.rxerr;
1819 bec->txerr = mod->bec.txerr;
1820 return 0;
1821}
1822
1823/*
1824 * Sysfs Attributes
1825 */
1826
1827static ssize_t termination_show(struct device *dev,
1828 struct device_attribute *attr,
1829 char *buf)
1830{
1831 struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
1832 int ret;
1833
1834 ret = ican3_send_inquiry(mod, INQUIRY_TERMINATION);
1835 if (ret)
1836 return ret;
1837
1838 if (!wait_for_completion_timeout(&mod->termination_comp, HZ)) {
1839 netdev_info(mod->ndev, "%s timed out\n", __func__);
1840 return -ETIMEDOUT;
1841 }
1842
1843 return sysfs_emit(buf, "%u\n", mod->termination_enabled);
1844}
1845
1846static ssize_t termination_store(struct device *dev,
1847 struct device_attribute *attr,
1848 const char *buf, size_t count)
1849{
1850 struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
1851 unsigned long enable;
1852 int ret;
1853
1854 if (kstrtoul(buf, 0, &enable))
1855 return -EINVAL;
1856
1857 ret = ican3_set_termination(mod, enable);
1858 if (ret)
1859 return ret;
1860
1861 return count;
1862}
1863
1864static ssize_t fwinfo_show(struct device *dev,
1865 struct device_attribute *attr,
1866 char *buf)
1867{
1868 struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
1869
1870 return scnprintf(buf, PAGE_SIZE, "%s\n", mod->fwinfo);
1871}
1872
1873static DEVICE_ATTR_RW(termination);
1874static DEVICE_ATTR_RO(fwinfo);
1875
1876static struct attribute *ican3_sysfs_attrs[] = {
1877 &dev_attr_termination.attr,
1878 &dev_attr_fwinfo.attr,
1879 NULL,
1880};
1881
1882static const struct attribute_group ican3_sysfs_attr_group = {
1883 .attrs = ican3_sysfs_attrs,
1884};
1885
1886/*
1887 * PCI Subsystem
1888 */
1889
1890static int ican3_probe(struct platform_device *pdev)
1891{
1892 struct janz_platform_data *pdata;
1893 struct net_device *ndev;
1894 struct ican3_dev *mod;
1895 struct resource *res;
1896 struct device *dev;
1897 int ret;
1898
1899 pdata = dev_get_platdata(&pdev->dev);
1900 if (!pdata)
1901 return -ENXIO;
1902
1903 dev_dbg(&pdev->dev, "probe: module number %d\n", pdata->modno);
1904
1905 /* save the struct device for printing */
1906 dev = &pdev->dev;
1907
1908 /* allocate the CAN device and private data */
1909 ndev = alloc_candev(sizeof(*mod), 0);
1910 if (!ndev) {
1911 dev_err(dev, "unable to allocate CANdev\n");
1912 ret = -ENOMEM;
1913 goto out_return;
1914 }
1915
1916 platform_set_drvdata(pdev, ndev);
1917 mod = netdev_priv(ndev);
1918 mod->ndev = ndev;
1919 mod->num = pdata->modno;
1920 netif_napi_add_weight(ndev, &mod->napi, ican3_napi, ICAN3_RX_BUFFERS);
1921 skb_queue_head_init(&mod->echoq);
1922 spin_lock_init(&mod->lock);
1923 init_completion(&mod->termination_comp);
1924 init_completion(&mod->buserror_comp);
1925
1926 /* setup device-specific sysfs attributes */
1927 ndev->sysfs_groups[0] = &ican3_sysfs_attr_group;
1928
1929 /* the first unallocated page in the DPM is 9 */
1930 mod->free_page = DPM_FREE_START;
1931
1932 ndev->netdev_ops = &ican3_netdev_ops;
1933 ndev->ethtool_ops = &ican3_ethtool_ops;
1934 ndev->flags |= IFF_ECHO;
1935 SET_NETDEV_DEV(ndev, &pdev->dev);
1936
1937 mod->can.clock.freq = ICAN3_CAN_CLOCK;
1938 mod->can.bittiming_const = &ican3_bittiming_const;
1939 mod->can.do_set_mode = ican3_set_mode;
1940 mod->can.do_get_berr_counter = ican3_get_berr_counter;
1941 mod->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES
1942 | CAN_CTRLMODE_BERR_REPORTING
1943 | CAN_CTRLMODE_ONE_SHOT;
1944
1945 /* find our IRQ number */
1946 mod->irq = platform_get_irq(pdev, 0);
1947 if (mod->irq < 0) {
1948 ret = -ENODEV;
1949 goto out_free_ndev;
1950 }
1951
1952 ndev->irq = mod->irq;
1953
1954 /* get access to the MODULbus registers for this module */
1955 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1956 if (!res) {
1957 dev_err(dev, "MODULbus registers not found\n");
1958 ret = -ENODEV;
1959 goto out_free_ndev;
1960 }
1961
1962 mod->dpm = ioremap(res->start, resource_size(res));
1963 if (!mod->dpm) {
1964 dev_err(dev, "MODULbus registers not ioremap\n");
1965 ret = -ENOMEM;
1966 goto out_free_ndev;
1967 }
1968
1969 mod->dpmctrl = mod->dpm + DPM_PAGE_SIZE;
1970
1971 /* get access to the control registers for this module */
1972 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1973 if (!res) {
1974 dev_err(dev, "CONTROL registers not found\n");
1975 ret = -ENODEV;
1976 goto out_iounmap_dpm;
1977 }
1978
1979 mod->ctrl = ioremap(res->start, resource_size(res));
1980 if (!mod->ctrl) {
1981 dev_err(dev, "CONTROL registers not ioremap\n");
1982 ret = -ENOMEM;
1983 goto out_iounmap_dpm;
1984 }
1985
1986 /* disable our IRQ, then hookup the IRQ handler */
1987 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
1988 ret = request_irq(mod->irq, ican3_irq, IRQF_SHARED, DRV_NAME, mod);
1989 if (ret) {
1990 dev_err(dev, "unable to request IRQ\n");
1991 goto out_iounmap_ctrl;
1992 }
1993
1994 /* reset and initialize the CAN controller into fast mode */
1995 napi_enable(&mod->napi);
1996 ret = ican3_startup_module(mod);
1997 if (ret) {
1998 dev_err(dev, "%s: unable to start CANdev\n", __func__);
1999 goto out_free_irq;
2000 }
2001
2002 /* register with the Linux CAN layer */
2003 ret = register_candev(ndev);
2004 if (ret) {
2005 dev_err(dev, "%s: unable to register CANdev\n", __func__);
2006 goto out_free_irq;
2007 }
2008
2009 netdev_info(mod->ndev, "module %d: registered CAN device\n", pdata->modno);
2010 return 0;
2011
2012out_free_irq:
2013 napi_disable(&mod->napi);
2014 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
2015 free_irq(mod->irq, mod);
2016out_iounmap_ctrl:
2017 iounmap(mod->ctrl);
2018out_iounmap_dpm:
2019 iounmap(mod->dpm);
2020out_free_ndev:
2021 free_candev(ndev);
2022out_return:
2023 return ret;
2024}
2025
2026static void ican3_remove(struct platform_device *pdev)
2027{
2028 struct net_device *ndev = platform_get_drvdata(pdev);
2029 struct ican3_dev *mod = netdev_priv(ndev);
2030
2031 /* unregister the netdevice, stop interrupts */
2032 unregister_netdev(ndev);
2033 napi_disable(&mod->napi);
2034 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
2035 free_irq(mod->irq, mod);
2036
2037 /* put the module into reset */
2038 ican3_shutdown_module(mod);
2039
2040 /* unmap all registers */
2041 iounmap(mod->ctrl);
2042 iounmap(mod->dpm);
2043
2044 free_candev(ndev);
2045}
2046
2047static struct platform_driver ican3_driver = {
2048 .driver = {
2049 .name = DRV_NAME,
2050 },
2051 .probe = ican3_probe,
2052 .remove_new = ican3_remove,
2053};
2054
2055module_platform_driver(ican3_driver);
2056
2057MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
2058MODULE_DESCRIPTION("Janz MODULbus VMOD-ICAN3 Driver");
2059MODULE_LICENSE("GPL");
2060MODULE_ALIAS("platform:janz-ican3");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Janz MODULbus VMOD-ICAN3 CAN Interface Driver
4 *
5 * Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/interrupt.h>
11#include <linux/delay.h>
12#include <linux/platform_device.h>
13
14#include <linux/netdevice.h>
15#include <linux/can.h>
16#include <linux/can/dev.h>
17#include <linux/can/skb.h>
18#include <linux/can/error.h>
19
20#include <linux/mfd/janz.h>
21#include <asm/io.h>
22
23/* the DPM has 64k of memory, organized into 256x 256 byte pages */
24#define DPM_NUM_PAGES 256
25#define DPM_PAGE_SIZE 256
26#define DPM_PAGE_ADDR(p) ((p) * DPM_PAGE_SIZE)
27
28/* JANZ ICAN3 "old-style" host interface queue page numbers */
29#define QUEUE_OLD_CONTROL 0
30#define QUEUE_OLD_RB0 1
31#define QUEUE_OLD_RB1 2
32#define QUEUE_OLD_WB0 3
33#define QUEUE_OLD_WB1 4
34
35/* Janz ICAN3 "old-style" host interface control registers */
36#define MSYNC_PEER 0x00 /* ICAN only */
37#define MSYNC_LOCL 0x01 /* host only */
38#define TARGET_RUNNING 0x02
39#define FIRMWARE_STAMP 0x60 /* big endian firmware stamp */
40
41#define MSYNC_RB0 0x01
42#define MSYNC_RB1 0x02
43#define MSYNC_RBLW 0x04
44#define MSYNC_RB_MASK (MSYNC_RB0 | MSYNC_RB1)
45
46#define MSYNC_WB0 0x10
47#define MSYNC_WB1 0x20
48#define MSYNC_WBLW 0x40
49#define MSYNC_WB_MASK (MSYNC_WB0 | MSYNC_WB1)
50
51/* Janz ICAN3 "new-style" host interface queue page numbers */
52#define QUEUE_TOHOST 5
53#define QUEUE_FROMHOST_MID 6
54#define QUEUE_FROMHOST_HIGH 7
55#define QUEUE_FROMHOST_LOW 8
56
57/* The first free page in the DPM is #9 */
58#define DPM_FREE_START 9
59
60/* Janz ICAN3 "new-style" and "fast" host interface descriptor flags */
61#define DESC_VALID 0x80
62#define DESC_WRAP 0x40
63#define DESC_INTERRUPT 0x20
64#define DESC_IVALID 0x10
65#define DESC_LEN(len) (len)
66
67/* Janz ICAN3 Firmware Messages */
68#define MSG_CONNECTI 0x02
69#define MSG_DISCONNECT 0x03
70#define MSG_IDVERS 0x04
71#define MSG_MSGLOST 0x05
72#define MSG_NEWHOSTIF 0x08
73#define MSG_INQUIRY 0x0a
74#define MSG_SETAFILMASK 0x10
75#define MSG_INITFDPMQUEUE 0x11
76#define MSG_HWCONF 0x12
77#define MSG_FMSGLOST 0x15
78#define MSG_CEVTIND 0x37
79#define MSG_CBTRREQ 0x41
80#define MSG_COFFREQ 0x42
81#define MSG_CONREQ 0x43
82#define MSG_CCONFREQ 0x47
83#define MSG_NMTS 0xb0
84#define MSG_LMTS 0xb4
85
86/*
87 * Janz ICAN3 CAN Inquiry Message Types
88 *
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 :(
93 */
94#define INQUIRY_STATUS 0x00
95#define INQUIRY_TERMINATION 0x01
96#define INQUIRY_EXTENDED 0x04
97
98/* Janz ICAN3 CAN Set Acceptance Filter Mask Message Types */
99#define SETAFILMASK_REJECT 0x00
100#define SETAFILMASK_FASTIF 0x02
101
102/* Janz ICAN3 CAN Hardware Configuration Message Types */
103#define HWCONF_TERMINATE_ON 0x01
104#define HWCONF_TERMINATE_OFF 0x00
105
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
112
113#define CEVTIND_CHIP_SJA1000 0x02
114
115#define ICAN3_BUSERR_QUOTA_MAX 255
116
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
123
124#define ICAN3_CAN_TYPE_MASK 0x0f
125#define ICAN3_CAN_TYPE_SFF 0x00
126#define ICAN3_CAN_TYPE_EFF 0x01
127
128#define ICAN3_CAN_DLC_MASK 0x0f
129
130/* Janz ICAN3 NMTS subtypes */
131#define NMTS_CREATE_NODE_REQ 0x0
132#define NMTS_SLAVE_STATE_IND 0x8
133#define NMTS_SLAVE_EVENT_IND 0x9
134
135/* Janz ICAN3 LMTS subtypes */
136#define LMTS_BUSON_REQ 0x0
137#define LMTS_BUSOFF_REQ 0x1
138#define LMTS_CAN_CONF_REQ 0x2
139
140/* Janz ICAN3 NMTS Event indications */
141#define NE_LOCAL_OCCURRED 0x3
142#define NE_LOCAL_RESOLVED 0x2
143#define NE_REMOTE_OCCURRED 0xc
144#define NE_REMOTE_RESOLVED 0x8
145
146/*
147 * SJA1000 Status and Error Register Definitions
148 *
149 * Copied from drivers/net/can/sja1000/sja1000.h
150 */
151
152/* status register content */
153#define SR_BS 0x80
154#define SR_ES 0x40
155#define SR_TS 0x20
156#define SR_RS 0x10
157#define SR_TCS 0x08
158#define SR_TBS 0x04
159#define SR_DOS 0x02
160#define SR_RBS 0x01
161
162#define SR_CRIT (SR_BS|SR_ES)
163
164/* ECC register */
165#define ECC_SEG 0x1F
166#define ECC_DIR 0x20
167#define ECC_ERR 6
168#define ECC_BIT 0x00
169#define ECC_FORM 0x40
170#define ECC_STUFF 0x80
171#define ECC_MASK 0xc0
172
173/* Number of buffers for use in the "new-style" host interface */
174#define ICAN3_NEW_BUFFERS 16
175
176/* Number of buffers for use in the "fast" host interface */
177#define ICAN3_TX_BUFFERS 512
178#define ICAN3_RX_BUFFERS 1024
179
180/* SJA1000 Clock Input */
181#define ICAN3_CAN_CLOCK 8000000
182
183/* Janz ICAN3 firmware types */
184enum ican3_fwtype {
185 ICAN3_FWTYPE_ICANOS,
186 ICAN3_FWTYPE_CAL_CANOPEN,
187};
188
189/* Driver Name */
190#define DRV_NAME "janz-ican3"
191
192/* DPM Control Registers -- starts at offset 0x100 in the MODULbus registers */
193struct ican3_dpm_control {
194 /* window address register */
195 u8 window_address;
196 u8 unused1;
197
198 /*
199 * Read access: clear interrupt from microcontroller
200 * Write access: send interrupt to microcontroller
201 */
202 u8 interrupt;
203 u8 unused2;
204
205 /* write-only: reset all hardware on the module */
206 u8 hwreset;
207 u8 unused3;
208
209 /* write-only: generate an interrupt to the TPU */
210 u8 tpuinterrupt;
211};
212
213struct ican3_dev {
214
215 /* must be the first member */
216 struct can_priv can;
217
218 /* CAN network device */
219 struct net_device *ndev;
220 struct napi_struct napi;
221
222 /* module number */
223 unsigned int num;
224
225 /* base address of registers and IRQ */
226 struct janz_cmodio_onboard_regs __iomem *ctrl;
227 struct ican3_dpm_control __iomem *dpmctrl;
228 void __iomem *dpm;
229 int irq;
230
231 /* CAN bus termination status */
232 struct completion termination_comp;
233 bool termination_enabled;
234
235 /* CAN bus error status registers */
236 struct completion buserror_comp;
237 struct can_berr_counter bec;
238
239 /* firmware type */
240 enum ican3_fwtype fwtype;
241 char fwinfo[32];
242
243 /* old and new style host interface */
244 unsigned int iftype;
245
246 /* queue for echo packets */
247 struct sk_buff_head echoq;
248
249 /*
250 * Any function which changes the current DPM page must hold this
251 * lock while it is performing data accesses. This ensures that the
252 * function will not be preempted and end up reading data from a
253 * different DPM page than it expects.
254 */
255 spinlock_t lock;
256
257 /* new host interface */
258 unsigned int rx_int;
259 unsigned int rx_num;
260 unsigned int tx_num;
261
262 /* fast host interface */
263 unsigned int fastrx_start;
264 unsigned int fastrx_num;
265 unsigned int fasttx_start;
266 unsigned int fasttx_num;
267
268 /* first free DPM page */
269 unsigned int free_page;
270};
271
272struct ican3_msg {
273 u8 control;
274 u8 spec;
275 __le16 len;
276 u8 data[252];
277};
278
279struct ican3_new_desc {
280 u8 control;
281 u8 pointer;
282};
283
284struct ican3_fast_desc {
285 u8 control;
286 u8 command;
287 u8 data[14];
288};
289
290/* write to the window basic address register */
291static inline void ican3_set_page(struct ican3_dev *mod, unsigned int page)
292{
293 BUG_ON(page >= DPM_NUM_PAGES);
294 iowrite8(page, &mod->dpmctrl->window_address);
295}
296
297/*
298 * ICAN3 "old-style" host interface
299 */
300
301/*
302 * Receive a message from the ICAN3 "old-style" firmware interface
303 *
304 * LOCKING: must hold mod->lock
305 *
306 * returns 0 on success, -ENOMEM when no message exists
307 */
308static int ican3_old_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
309{
310 unsigned int mbox, mbox_page;
311 u8 locl, peer, xord;
312
313 /* get the MSYNC registers */
314 ican3_set_page(mod, QUEUE_OLD_CONTROL);
315 peer = ioread8(mod->dpm + MSYNC_PEER);
316 locl = ioread8(mod->dpm + MSYNC_LOCL);
317 xord = locl ^ peer;
318
319 if ((xord & MSYNC_RB_MASK) == 0x00) {
320 netdev_dbg(mod->ndev, "no mbox for reading\n");
321 return -ENOMEM;
322 }
323
324 /* find the first free mbox to read */
325 if ((xord & MSYNC_RB_MASK) == MSYNC_RB_MASK)
326 mbox = (xord & MSYNC_RBLW) ? MSYNC_RB0 : MSYNC_RB1;
327 else
328 mbox = (xord & MSYNC_RB0) ? MSYNC_RB0 : MSYNC_RB1;
329
330 /* copy the message */
331 mbox_page = (mbox == MSYNC_RB0) ? QUEUE_OLD_RB0 : QUEUE_OLD_RB1;
332 ican3_set_page(mod, mbox_page);
333 memcpy_fromio(msg, mod->dpm, sizeof(*msg));
334
335 /*
336 * notify the firmware that the read buffer is available
337 * for it to fill again
338 */
339 locl ^= mbox;
340
341 ican3_set_page(mod, QUEUE_OLD_CONTROL);
342 iowrite8(locl, mod->dpm + MSYNC_LOCL);
343 return 0;
344}
345
346/*
347 * Send a message through the "old-style" firmware interface
348 *
349 * LOCKING: must hold mod->lock
350 *
351 * returns 0 on success, -ENOMEM when no free space exists
352 */
353static int ican3_old_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
354{
355 unsigned int mbox, mbox_page;
356 u8 locl, peer, xord;
357
358 /* get the MSYNC registers */
359 ican3_set_page(mod, QUEUE_OLD_CONTROL);
360 peer = ioread8(mod->dpm + MSYNC_PEER);
361 locl = ioread8(mod->dpm + MSYNC_LOCL);
362 xord = locl ^ peer;
363
364 if ((xord & MSYNC_WB_MASK) == MSYNC_WB_MASK) {
365 netdev_err(mod->ndev, "no mbox for writing\n");
366 return -ENOMEM;
367 }
368
369 /* calculate a free mbox to use */
370 mbox = (xord & MSYNC_WB0) ? MSYNC_WB1 : MSYNC_WB0;
371
372 /* copy the message to the DPM */
373 mbox_page = (mbox == MSYNC_WB0) ? QUEUE_OLD_WB0 : QUEUE_OLD_WB1;
374 ican3_set_page(mod, mbox_page);
375 memcpy_toio(mod->dpm, msg, sizeof(*msg));
376
377 locl ^= mbox;
378 if (mbox == MSYNC_WB1)
379 locl |= MSYNC_WBLW;
380
381 ican3_set_page(mod, QUEUE_OLD_CONTROL);
382 iowrite8(locl, mod->dpm + MSYNC_LOCL);
383 return 0;
384}
385
386/*
387 * ICAN3 "new-style" Host Interface Setup
388 */
389
390static void ican3_init_new_host_interface(struct ican3_dev *mod)
391{
392 struct ican3_new_desc desc;
393 unsigned long flags;
394 void __iomem *dst;
395 int i;
396
397 spin_lock_irqsave(&mod->lock, flags);
398
399 /* setup the internal datastructures for RX */
400 mod->rx_num = 0;
401 mod->rx_int = 0;
402
403 /* tohost queue descriptors are in page 5 */
404 ican3_set_page(mod, QUEUE_TOHOST);
405 dst = mod->dpm;
406
407 /* initialize the tohost (rx) queue descriptors: pages 9-24 */
408 for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
409 desc.control = DESC_INTERRUPT | DESC_LEN(1); /* I L=1 */
410 desc.pointer = mod->free_page;
411
412 /* set wrap flag on last buffer */
413 if (i == ICAN3_NEW_BUFFERS - 1)
414 desc.control |= DESC_WRAP;
415
416 memcpy_toio(dst, &desc, sizeof(desc));
417 dst += sizeof(desc);
418 mod->free_page++;
419 }
420
421 /* fromhost (tx) mid queue descriptors are in page 6 */
422 ican3_set_page(mod, QUEUE_FROMHOST_MID);
423 dst = mod->dpm;
424
425 /* setup the internal datastructures for TX */
426 mod->tx_num = 0;
427
428 /* initialize the fromhost mid queue descriptors: pages 25-40 */
429 for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
430 desc.control = DESC_VALID | DESC_LEN(1); /* V L=1 */
431 desc.pointer = mod->free_page;
432
433 /* set wrap flag on last buffer */
434 if (i == ICAN3_NEW_BUFFERS - 1)
435 desc.control |= DESC_WRAP;
436
437 memcpy_toio(dst, &desc, sizeof(desc));
438 dst += sizeof(desc);
439 mod->free_page++;
440 }
441
442 /* fromhost hi queue descriptors are in page 7 */
443 ican3_set_page(mod, QUEUE_FROMHOST_HIGH);
444 dst = mod->dpm;
445
446 /* initialize only a single buffer in the fromhost hi queue (unused) */
447 desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
448 desc.pointer = mod->free_page;
449 memcpy_toio(dst, &desc, sizeof(desc));
450 mod->free_page++;
451
452 /* fromhost low queue descriptors are in page 8 */
453 ican3_set_page(mod, QUEUE_FROMHOST_LOW);
454 dst = mod->dpm;
455
456 /* initialize only a single buffer in the fromhost low queue (unused) */
457 desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
458 desc.pointer = mod->free_page;
459 memcpy_toio(dst, &desc, sizeof(desc));
460 mod->free_page++;
461
462 spin_unlock_irqrestore(&mod->lock, flags);
463}
464
465/*
466 * ICAN3 Fast Host Interface Setup
467 */
468
469static void ican3_init_fast_host_interface(struct ican3_dev *mod)
470{
471 struct ican3_fast_desc desc;
472 unsigned long flags;
473 unsigned int addr;
474 void __iomem *dst;
475 int i;
476
477 spin_lock_irqsave(&mod->lock, flags);
478
479 /* save the start recv page */
480 mod->fastrx_start = mod->free_page;
481 mod->fastrx_num = 0;
482
483 /* build a single fast tohost queue descriptor */
484 memset(&desc, 0, sizeof(desc));
485 desc.control = 0x00;
486 desc.command = 1;
487
488 /* build the tohost queue descriptor ring in memory */
489 addr = 0;
490 for (i = 0; i < ICAN3_RX_BUFFERS; i++) {
491
492 /* set the wrap bit on the last buffer */
493 if (i == ICAN3_RX_BUFFERS - 1)
494 desc.control |= DESC_WRAP;
495
496 /* switch to the correct page */
497 ican3_set_page(mod, mod->free_page);
498
499 /* copy the descriptor to the DPM */
500 dst = mod->dpm + addr;
501 memcpy_toio(dst, &desc, sizeof(desc));
502 addr += sizeof(desc);
503
504 /* move to the next page if necessary */
505 if (addr >= DPM_PAGE_SIZE) {
506 addr = 0;
507 mod->free_page++;
508 }
509 }
510
511 /* make sure we page-align the next queue */
512 if (addr != 0)
513 mod->free_page++;
514
515 /* save the start xmit page */
516 mod->fasttx_start = mod->free_page;
517 mod->fasttx_num = 0;
518
519 /* build a single fast fromhost queue descriptor */
520 memset(&desc, 0, sizeof(desc));
521 desc.control = DESC_VALID;
522 desc.command = 1;
523
524 /* build the fromhost queue descriptor ring in memory */
525 addr = 0;
526 for (i = 0; i < ICAN3_TX_BUFFERS; i++) {
527
528 /* set the wrap bit on the last buffer */
529 if (i == ICAN3_TX_BUFFERS - 1)
530 desc.control |= DESC_WRAP;
531
532 /* switch to the correct page */
533 ican3_set_page(mod, mod->free_page);
534
535 /* copy the descriptor to the DPM */
536 dst = mod->dpm + addr;
537 memcpy_toio(dst, &desc, sizeof(desc));
538 addr += sizeof(desc);
539
540 /* move to the next page if necessary */
541 if (addr >= DPM_PAGE_SIZE) {
542 addr = 0;
543 mod->free_page++;
544 }
545 }
546
547 spin_unlock_irqrestore(&mod->lock, flags);
548}
549
550/*
551 * ICAN3 "new-style" Host Interface Message Helpers
552 */
553
554/*
555 * LOCKING: must hold mod->lock
556 */
557static int ican3_new_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
558{
559 struct ican3_new_desc desc;
560 void __iomem *desc_addr = mod->dpm + (mod->tx_num * sizeof(desc));
561
562 /* switch to the fromhost mid queue, and read the buffer descriptor */
563 ican3_set_page(mod, QUEUE_FROMHOST_MID);
564 memcpy_fromio(&desc, desc_addr, sizeof(desc));
565
566 if (!(desc.control & DESC_VALID)) {
567 netdev_dbg(mod->ndev, "%s: no free buffers\n", __func__);
568 return -ENOMEM;
569 }
570
571 /* switch to the data page, copy the data */
572 ican3_set_page(mod, desc.pointer);
573 memcpy_toio(mod->dpm, msg, sizeof(*msg));
574
575 /* switch back to the descriptor, set the valid bit, write it back */
576 ican3_set_page(mod, QUEUE_FROMHOST_MID);
577 desc.control ^= DESC_VALID;
578 memcpy_toio(desc_addr, &desc, sizeof(desc));
579
580 /* update the tx number */
581 mod->tx_num = (desc.control & DESC_WRAP) ? 0 : (mod->tx_num + 1);
582 return 0;
583}
584
585/*
586 * LOCKING: must hold mod->lock
587 */
588static int ican3_new_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
589{
590 struct ican3_new_desc desc;
591 void __iomem *desc_addr = mod->dpm + (mod->rx_num * sizeof(desc));
592
593 /* switch to the tohost queue, and read the buffer descriptor */
594 ican3_set_page(mod, QUEUE_TOHOST);
595 memcpy_fromio(&desc, desc_addr, sizeof(desc));
596
597 if (!(desc.control & DESC_VALID)) {
598 netdev_dbg(mod->ndev, "%s: no buffers to recv\n", __func__);
599 return -ENOMEM;
600 }
601
602 /* switch to the data page, copy the data */
603 ican3_set_page(mod, desc.pointer);
604 memcpy_fromio(msg, mod->dpm, sizeof(*msg));
605
606 /* switch back to the descriptor, toggle the valid bit, write it back */
607 ican3_set_page(mod, QUEUE_TOHOST);
608 desc.control ^= DESC_VALID;
609 memcpy_toio(desc_addr, &desc, sizeof(desc));
610
611 /* update the rx number */
612 mod->rx_num = (desc.control & DESC_WRAP) ? 0 : (mod->rx_num + 1);
613 return 0;
614}
615
616/*
617 * Message Send / Recv Helpers
618 */
619
620static int ican3_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
621{
622 unsigned long flags;
623 int ret;
624
625 spin_lock_irqsave(&mod->lock, flags);
626
627 if (mod->iftype == 0)
628 ret = ican3_old_send_msg(mod, msg);
629 else
630 ret = ican3_new_send_msg(mod, msg);
631
632 spin_unlock_irqrestore(&mod->lock, flags);
633 return ret;
634}
635
636static int ican3_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
637{
638 unsigned long flags;
639 int ret;
640
641 spin_lock_irqsave(&mod->lock, flags);
642
643 if (mod->iftype == 0)
644 ret = ican3_old_recv_msg(mod, msg);
645 else
646 ret = ican3_new_recv_msg(mod, msg);
647
648 spin_unlock_irqrestore(&mod->lock, flags);
649 return ret;
650}
651
652/*
653 * Quick Pre-constructed Messages
654 */
655
656static int ican3_msg_connect(struct ican3_dev *mod)
657{
658 struct ican3_msg msg;
659
660 memset(&msg, 0, sizeof(msg));
661 msg.spec = MSG_CONNECTI;
662 msg.len = cpu_to_le16(0);
663
664 return ican3_send_msg(mod, &msg);
665}
666
667static int ican3_msg_disconnect(struct ican3_dev *mod)
668{
669 struct ican3_msg msg;
670
671 memset(&msg, 0, sizeof(msg));
672 msg.spec = MSG_DISCONNECT;
673 msg.len = cpu_to_le16(0);
674
675 return ican3_send_msg(mod, &msg);
676}
677
678static int ican3_msg_newhostif(struct ican3_dev *mod)
679{
680 struct ican3_msg msg;
681 int ret;
682
683 memset(&msg, 0, sizeof(msg));
684 msg.spec = MSG_NEWHOSTIF;
685 msg.len = cpu_to_le16(0);
686
687 /* If we're not using the old interface, switching seems bogus */
688 WARN_ON(mod->iftype != 0);
689
690 ret = ican3_send_msg(mod, &msg);
691 if (ret)
692 return ret;
693
694 /* mark the module as using the new host interface */
695 mod->iftype = 1;
696 return 0;
697}
698
699static int ican3_msg_fasthostif(struct ican3_dev *mod)
700{
701 struct ican3_msg msg;
702 unsigned int addr;
703
704 memset(&msg, 0, sizeof(msg));
705 msg.spec = MSG_INITFDPMQUEUE;
706 msg.len = cpu_to_le16(8);
707
708 /* write the tohost queue start address */
709 addr = DPM_PAGE_ADDR(mod->fastrx_start);
710 msg.data[0] = addr & 0xff;
711 msg.data[1] = (addr >> 8) & 0xff;
712 msg.data[2] = (addr >> 16) & 0xff;
713 msg.data[3] = (addr >> 24) & 0xff;
714
715 /* write the fromhost queue start address */
716 addr = DPM_PAGE_ADDR(mod->fasttx_start);
717 msg.data[4] = addr & 0xff;
718 msg.data[5] = (addr >> 8) & 0xff;
719 msg.data[6] = (addr >> 16) & 0xff;
720 msg.data[7] = (addr >> 24) & 0xff;
721
722 /* If we're not using the new interface yet, we cannot do this */
723 WARN_ON(mod->iftype != 1);
724
725 return ican3_send_msg(mod, &msg);
726}
727
728/*
729 * Setup the CAN filter to either accept or reject all
730 * messages from the CAN bus.
731 */
732static int ican3_set_id_filter(struct ican3_dev *mod, bool accept)
733{
734 struct ican3_msg msg;
735 int ret;
736
737 /* Standard Frame Format */
738 memset(&msg, 0, sizeof(msg));
739 msg.spec = MSG_SETAFILMASK;
740 msg.len = cpu_to_le16(5);
741 msg.data[0] = 0x00; /* IDLo LSB */
742 msg.data[1] = 0x00; /* IDLo MSB */
743 msg.data[2] = 0xff; /* IDHi LSB */
744 msg.data[3] = 0x07; /* IDHi MSB */
745
746 /* accept all frames for fast host if, or reject all frames */
747 msg.data[4] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
748
749 ret = ican3_send_msg(mod, &msg);
750 if (ret)
751 return ret;
752
753 /* Extended Frame Format */
754 memset(&msg, 0, sizeof(msg));
755 msg.spec = MSG_SETAFILMASK;
756 msg.len = cpu_to_le16(13);
757 msg.data[0] = 0; /* MUX = 0 */
758 msg.data[1] = 0x00; /* IDLo LSB */
759 msg.data[2] = 0x00;
760 msg.data[3] = 0x00;
761 msg.data[4] = 0x20; /* IDLo MSB */
762 msg.data[5] = 0xff; /* IDHi LSB */
763 msg.data[6] = 0xff;
764 msg.data[7] = 0xff;
765 msg.data[8] = 0x3f; /* IDHi MSB */
766
767 /* accept all frames for fast host if, or reject all frames */
768 msg.data[9] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
769
770 return ican3_send_msg(mod, &msg);
771}
772
773/*
774 * Bring the CAN bus online or offline
775 */
776static int ican3_set_bus_state(struct ican3_dev *mod, bool on)
777{
778 struct can_bittiming *bt = &mod->can.bittiming;
779 struct ican3_msg msg;
780 u8 btr0, btr1;
781 int res;
782
783 /* This algorithm was stolen from drivers/net/can/sja1000/sja1000.c */
784 /* The bittiming register command for the ICAN3 just sets the bit timing */
785 /* registers on the SJA1000 chip directly */
786 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
787 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
788 (((bt->phase_seg2 - 1) & 0x7) << 4);
789 if (mod->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
790 btr1 |= 0x80;
791
792 if (mod->fwtype == ICAN3_FWTYPE_ICANOS) {
793 if (on) {
794 /* set bittiming */
795 memset(&msg, 0, sizeof(msg));
796 msg.spec = MSG_CBTRREQ;
797 msg.len = cpu_to_le16(4);
798 msg.data[0] = 0x00;
799 msg.data[1] = 0x00;
800 msg.data[2] = btr0;
801 msg.data[3] = btr1;
802
803 res = ican3_send_msg(mod, &msg);
804 if (res)
805 return res;
806 }
807
808 /* can-on/off request */
809 memset(&msg, 0, sizeof(msg));
810 msg.spec = on ? MSG_CONREQ : MSG_COFFREQ;
811 msg.len = cpu_to_le16(0);
812
813 return ican3_send_msg(mod, &msg);
814
815 } else if (mod->fwtype == ICAN3_FWTYPE_CAL_CANOPEN) {
816 /* bittiming + can-on/off request */
817 memset(&msg, 0, sizeof(msg));
818 msg.spec = MSG_LMTS;
819 if (on) {
820 msg.len = cpu_to_le16(4);
821 msg.data[0] = LMTS_BUSON_REQ;
822 msg.data[1] = 0;
823 msg.data[2] = btr0;
824 msg.data[3] = btr1;
825 } else {
826 msg.len = cpu_to_le16(2);
827 msg.data[0] = LMTS_BUSOFF_REQ;
828 msg.data[1] = 0;
829 }
830 res = ican3_send_msg(mod, &msg);
831 if (res)
832 return res;
833
834 if (on) {
835 /* create NMT Slave Node for error processing
836 * class 2 (with error capability, see CiA/DS203-1)
837 * id 1
838 * name locnod1 (must be exactly 7 bytes)
839 */
840 memset(&msg, 0, sizeof(msg));
841 msg.spec = MSG_NMTS;
842 msg.len = cpu_to_le16(11);
843 msg.data[0] = NMTS_CREATE_NODE_REQ;
844 msg.data[1] = 0;
845 msg.data[2] = 2; /* node class */
846 msg.data[3] = 1; /* node id */
847 strcpy(msg.data + 4, "locnod1"); /* node name */
848 return ican3_send_msg(mod, &msg);
849 }
850 return 0;
851 }
852 return -ENOTSUPP;
853}
854
855static int ican3_set_termination(struct ican3_dev *mod, bool on)
856{
857 struct ican3_msg msg;
858
859 memset(&msg, 0, sizeof(msg));
860 msg.spec = MSG_HWCONF;
861 msg.len = cpu_to_le16(2);
862 msg.data[0] = 0x00;
863 msg.data[1] = on ? HWCONF_TERMINATE_ON : HWCONF_TERMINATE_OFF;
864
865 return ican3_send_msg(mod, &msg);
866}
867
868static int ican3_send_inquiry(struct ican3_dev *mod, u8 subspec)
869{
870 struct ican3_msg msg;
871
872 memset(&msg, 0, sizeof(msg));
873 msg.spec = MSG_INQUIRY;
874 msg.len = cpu_to_le16(2);
875 msg.data[0] = subspec;
876 msg.data[1] = 0x00;
877
878 return ican3_send_msg(mod, &msg);
879}
880
881static int ican3_set_buserror(struct ican3_dev *mod, u8 quota)
882{
883 struct ican3_msg msg;
884
885 if (mod->fwtype == ICAN3_FWTYPE_ICANOS) {
886 memset(&msg, 0, sizeof(msg));
887 msg.spec = MSG_CCONFREQ;
888 msg.len = cpu_to_le16(2);
889 msg.data[0] = 0x00;
890 msg.data[1] = quota;
891 } else if (mod->fwtype == ICAN3_FWTYPE_CAL_CANOPEN) {
892 memset(&msg, 0, sizeof(msg));
893 msg.spec = MSG_LMTS;
894 msg.len = cpu_to_le16(4);
895 msg.data[0] = LMTS_CAN_CONF_REQ;
896 msg.data[1] = 0x00;
897 msg.data[2] = 0x00;
898 msg.data[3] = quota;
899 } else {
900 return -ENOTSUPP;
901 }
902 return ican3_send_msg(mod, &msg);
903}
904
905/*
906 * ICAN3 to Linux CAN Frame Conversion
907 */
908
909static void ican3_to_can_frame(struct ican3_dev *mod,
910 struct ican3_fast_desc *desc,
911 struct can_frame *cf)
912{
913 if ((desc->command & ICAN3_CAN_TYPE_MASK) == ICAN3_CAN_TYPE_SFF) {
914 if (desc->data[1] & ICAN3_SFF_RTR)
915 cf->can_id |= CAN_RTR_FLAG;
916
917 cf->can_id |= desc->data[0] << 3;
918 cf->can_id |= (desc->data[1] & 0xe0) >> 5;
919 cf->can_dlc = get_can_dlc(desc->data[1] & ICAN3_CAN_DLC_MASK);
920 memcpy(cf->data, &desc->data[2], cf->can_dlc);
921 } else {
922 cf->can_dlc = get_can_dlc(desc->data[0] & ICAN3_CAN_DLC_MASK);
923 if (desc->data[0] & ICAN3_EFF_RTR)
924 cf->can_id |= CAN_RTR_FLAG;
925
926 if (desc->data[0] & ICAN3_EFF) {
927 cf->can_id |= CAN_EFF_FLAG;
928 cf->can_id |= desc->data[2] << 21; /* 28-21 */
929 cf->can_id |= desc->data[3] << 13; /* 20-13 */
930 cf->can_id |= desc->data[4] << 5; /* 12-5 */
931 cf->can_id |= (desc->data[5] & 0xf8) >> 3;
932 } else {
933 cf->can_id |= desc->data[2] << 3; /* 10-3 */
934 cf->can_id |= desc->data[3] >> 5; /* 2-0 */
935 }
936
937 memcpy(cf->data, &desc->data[6], cf->can_dlc);
938 }
939}
940
941static void can_frame_to_ican3(struct ican3_dev *mod,
942 struct can_frame *cf,
943 struct ican3_fast_desc *desc)
944{
945 /* clear out any stale data in the descriptor */
946 memset(desc->data, 0, sizeof(desc->data));
947
948 /* we always use the extended format, with the ECHO flag set */
949 desc->command = ICAN3_CAN_TYPE_EFF;
950 desc->data[0] |= cf->can_dlc;
951 desc->data[1] |= ICAN3_ECHO;
952
953 /* support single transmission (no retries) mode */
954 if (mod->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
955 desc->data[1] |= ICAN3_SNGL;
956
957 if (cf->can_id & CAN_RTR_FLAG)
958 desc->data[0] |= ICAN3_EFF_RTR;
959
960 /* pack the id into the correct places */
961 if (cf->can_id & CAN_EFF_FLAG) {
962 desc->data[0] |= ICAN3_EFF;
963 desc->data[2] = (cf->can_id & 0x1fe00000) >> 21; /* 28-21 */
964 desc->data[3] = (cf->can_id & 0x001fe000) >> 13; /* 20-13 */
965 desc->data[4] = (cf->can_id & 0x00001fe0) >> 5; /* 12-5 */
966 desc->data[5] = (cf->can_id & 0x0000001f) << 3; /* 4-0 */
967 } else {
968 desc->data[2] = (cf->can_id & 0x7F8) >> 3; /* bits 10-3 */
969 desc->data[3] = (cf->can_id & 0x007) << 5; /* bits 2-0 */
970 }
971
972 /* copy the data bits into the descriptor */
973 memcpy(&desc->data[6], cf->data, cf->can_dlc);
974}
975
976/*
977 * Interrupt Handling
978 */
979
980/*
981 * Handle an ID + Version message response from the firmware. We never generate
982 * this message in production code, but it is very useful when debugging to be
983 * able to display this message.
984 */
985static void ican3_handle_idvers(struct ican3_dev *mod, struct ican3_msg *msg)
986{
987 netdev_dbg(mod->ndev, "IDVERS response: %s\n", msg->data);
988}
989
990static void ican3_handle_msglost(struct ican3_dev *mod, struct ican3_msg *msg)
991{
992 struct net_device *dev = mod->ndev;
993 struct net_device_stats *stats = &dev->stats;
994 struct can_frame *cf;
995 struct sk_buff *skb;
996
997 /*
998 * Report that communication messages with the microcontroller firmware
999 * are being lost. These are never CAN frames, so we do not generate an
1000 * error frame for userspace
1001 */
1002 if (msg->spec == MSG_MSGLOST) {
1003 netdev_err(mod->ndev, "lost %d control messages\n", msg->data[0]);
1004 return;
1005 }
1006
1007 /*
1008 * Oops, this indicates that we have lost messages in the fast queue,
1009 * which are exclusively CAN messages. Our driver isn't reading CAN
1010 * frames fast enough.
1011 *
1012 * We'll pretend that the SJA1000 told us that it ran out of buffer
1013 * space, because there is not a better message for this.
1014 */
1015 skb = alloc_can_err_skb(dev, &cf);
1016 if (skb) {
1017 cf->can_id |= CAN_ERR_CRTL;
1018 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
1019 stats->rx_over_errors++;
1020 stats->rx_errors++;
1021 netif_rx(skb);
1022 }
1023}
1024
1025/*
1026 * Handle CAN Event Indication Messages from the firmware
1027 *
1028 * The ICAN3 firmware provides the values of some SJA1000 registers when it
1029 * generates this message. The code below is largely copied from the
1030 * drivers/net/can/sja1000/sja1000.c file, and adapted as necessary
1031 */
1032static int ican3_handle_cevtind(struct ican3_dev *mod, struct ican3_msg *msg)
1033{
1034 struct net_device *dev = mod->ndev;
1035 struct net_device_stats *stats = &dev->stats;
1036 enum can_state state = mod->can.state;
1037 u8 isrc, ecc, status, rxerr, txerr;
1038 struct can_frame *cf;
1039 struct sk_buff *skb;
1040
1041 /* we can only handle the SJA1000 part */
1042 if (msg->data[1] != CEVTIND_CHIP_SJA1000) {
1043 netdev_err(mod->ndev, "unable to handle errors on non-SJA1000\n");
1044 return -ENODEV;
1045 }
1046
1047 /* check the message length for sanity */
1048 if (le16_to_cpu(msg->len) < 6) {
1049 netdev_err(mod->ndev, "error message too short\n");
1050 return -EINVAL;
1051 }
1052
1053 isrc = msg->data[0];
1054 ecc = msg->data[2];
1055 status = msg->data[3];
1056 rxerr = msg->data[4];
1057 txerr = msg->data[5];
1058
1059 /*
1060 * This hardware lacks any support other than bus error messages to
1061 * determine if packet transmission has failed.
1062 *
1063 * When TX errors happen, one echo skb needs to be dropped from the
1064 * front of the queue.
1065 *
1066 * A small bit of code is duplicated here and below, to avoid error
1067 * skb allocation when it will just be freed immediately.
1068 */
1069 if (isrc == CEVTIND_BEI) {
1070 int ret;
1071 netdev_dbg(mod->ndev, "bus error interrupt\n");
1072
1073 /* TX error */
1074 if (!(ecc & ECC_DIR)) {
1075 kfree_skb(skb_dequeue(&mod->echoq));
1076 stats->tx_errors++;
1077 } else {
1078 stats->rx_errors++;
1079 }
1080
1081 /*
1082 * The controller automatically disables bus-error interrupts
1083 * and therefore we must re-enable them.
1084 */
1085 ret = ican3_set_buserror(mod, 1);
1086 if (ret) {
1087 netdev_err(mod->ndev, "unable to re-enable bus-error\n");
1088 return ret;
1089 }
1090
1091 /* bus error reporting is off, return immediately */
1092 if (!(mod->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1093 return 0;
1094 }
1095
1096 skb = alloc_can_err_skb(dev, &cf);
1097 if (skb == NULL)
1098 return -ENOMEM;
1099
1100 /* data overrun interrupt */
1101 if (isrc == CEVTIND_DOI || isrc == CEVTIND_LOST) {
1102 netdev_dbg(mod->ndev, "data overrun interrupt\n");
1103 cf->can_id |= CAN_ERR_CRTL;
1104 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
1105 stats->rx_over_errors++;
1106 stats->rx_errors++;
1107 }
1108
1109 /* error warning + passive interrupt */
1110 if (isrc == CEVTIND_EI) {
1111 netdev_dbg(mod->ndev, "error warning + passive interrupt\n");
1112 if (status & SR_BS) {
1113 state = CAN_STATE_BUS_OFF;
1114 cf->can_id |= CAN_ERR_BUSOFF;
1115 mod->can.can_stats.bus_off++;
1116 can_bus_off(dev);
1117 } else if (status & SR_ES) {
1118 if (rxerr >= 128 || txerr >= 128)
1119 state = CAN_STATE_ERROR_PASSIVE;
1120 else
1121 state = CAN_STATE_ERROR_WARNING;
1122 } else {
1123 state = CAN_STATE_ERROR_ACTIVE;
1124 }
1125 }
1126
1127 /* bus error interrupt */
1128 if (isrc == CEVTIND_BEI) {
1129 mod->can.can_stats.bus_error++;
1130 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
1131
1132 switch (ecc & ECC_MASK) {
1133 case ECC_BIT:
1134 cf->data[2] |= CAN_ERR_PROT_BIT;
1135 break;
1136 case ECC_FORM:
1137 cf->data[2] |= CAN_ERR_PROT_FORM;
1138 break;
1139 case ECC_STUFF:
1140 cf->data[2] |= CAN_ERR_PROT_STUFF;
1141 break;
1142 default:
1143 cf->data[3] = ecc & ECC_SEG;
1144 break;
1145 }
1146
1147 if (!(ecc & ECC_DIR))
1148 cf->data[2] |= CAN_ERR_PROT_TX;
1149
1150 cf->data[6] = txerr;
1151 cf->data[7] = rxerr;
1152 }
1153
1154 if (state != mod->can.state && (state == CAN_STATE_ERROR_WARNING ||
1155 state == CAN_STATE_ERROR_PASSIVE)) {
1156 cf->can_id |= CAN_ERR_CRTL;
1157 if (state == CAN_STATE_ERROR_WARNING) {
1158 mod->can.can_stats.error_warning++;
1159 cf->data[1] = (txerr > rxerr) ?
1160 CAN_ERR_CRTL_TX_WARNING :
1161 CAN_ERR_CRTL_RX_WARNING;
1162 } else {
1163 mod->can.can_stats.error_passive++;
1164 cf->data[1] = (txerr > rxerr) ?
1165 CAN_ERR_CRTL_TX_PASSIVE :
1166 CAN_ERR_CRTL_RX_PASSIVE;
1167 }
1168
1169 cf->data[6] = txerr;
1170 cf->data[7] = rxerr;
1171 }
1172
1173 mod->can.state = state;
1174 netif_rx(skb);
1175 return 0;
1176}
1177
1178static void ican3_handle_inquiry(struct ican3_dev *mod, struct ican3_msg *msg)
1179{
1180 switch (msg->data[0]) {
1181 case INQUIRY_STATUS:
1182 case INQUIRY_EXTENDED:
1183 mod->bec.rxerr = msg->data[5];
1184 mod->bec.txerr = msg->data[6];
1185 complete(&mod->buserror_comp);
1186 break;
1187 case INQUIRY_TERMINATION:
1188 mod->termination_enabled = msg->data[6] & HWCONF_TERMINATE_ON;
1189 complete(&mod->termination_comp);
1190 break;
1191 default:
1192 netdev_err(mod->ndev, "received an unknown inquiry response\n");
1193 break;
1194 }
1195}
1196
1197/* Handle NMTS Slave Event Indication Messages from the firmware */
1198static void ican3_handle_nmtsind(struct ican3_dev *mod, struct ican3_msg *msg)
1199{
1200 u16 subspec;
1201
1202 subspec = msg->data[0] + msg->data[1] * 0x100;
1203 if (subspec == NMTS_SLAVE_EVENT_IND) {
1204 switch (msg->data[2]) {
1205 case NE_LOCAL_OCCURRED:
1206 case NE_LOCAL_RESOLVED:
1207 /* now follows the same message as Raw ICANOS CEVTIND
1208 * shift the data at the same place and call this method
1209 */
1210 le16_add_cpu(&msg->len, -3);
1211 memmove(msg->data, msg->data + 3, le16_to_cpu(msg->len));
1212 ican3_handle_cevtind(mod, msg);
1213 break;
1214 case NE_REMOTE_OCCURRED:
1215 case NE_REMOTE_RESOLVED:
1216 /* should not occurre, ignore */
1217 break;
1218 default:
1219 netdev_warn(mod->ndev, "unknown NMTS event indication %x\n",
1220 msg->data[2]);
1221 break;
1222 }
1223 } else if (subspec == NMTS_SLAVE_STATE_IND) {
1224 /* ignore state indications */
1225 } else {
1226 netdev_warn(mod->ndev, "unhandled NMTS indication %x\n",
1227 subspec);
1228 return;
1229 }
1230}
1231
1232static void ican3_handle_unknown_message(struct ican3_dev *mod,
1233 struct ican3_msg *msg)
1234{
1235 netdev_warn(mod->ndev, "received unknown message: spec 0x%.2x length %d\n",
1236 msg->spec, le16_to_cpu(msg->len));
1237}
1238
1239/*
1240 * Handle a control message from the firmware
1241 */
1242static void ican3_handle_message(struct ican3_dev *mod, struct ican3_msg *msg)
1243{
1244 netdev_dbg(mod->ndev, "%s: modno %d spec 0x%.2x len %d bytes\n", __func__,
1245 mod->num, msg->spec, le16_to_cpu(msg->len));
1246
1247 switch (msg->spec) {
1248 case MSG_IDVERS:
1249 ican3_handle_idvers(mod, msg);
1250 break;
1251 case MSG_MSGLOST:
1252 case MSG_FMSGLOST:
1253 ican3_handle_msglost(mod, msg);
1254 break;
1255 case MSG_CEVTIND:
1256 ican3_handle_cevtind(mod, msg);
1257 break;
1258 case MSG_INQUIRY:
1259 ican3_handle_inquiry(mod, msg);
1260 break;
1261 case MSG_NMTS:
1262 ican3_handle_nmtsind(mod, msg);
1263 break;
1264 default:
1265 ican3_handle_unknown_message(mod, msg);
1266 break;
1267 }
1268}
1269
1270/*
1271 * The ican3 needs to store all echo skbs, and therefore cannot
1272 * use the generic infrastructure for this.
1273 */
1274static void ican3_put_echo_skb(struct ican3_dev *mod, struct sk_buff *skb)
1275{
1276 skb = can_create_echo_skb(skb);
1277 if (!skb)
1278 return;
1279
1280 /* save this skb for tx interrupt echo handling */
1281 skb_queue_tail(&mod->echoq, skb);
1282}
1283
1284static unsigned int ican3_get_echo_skb(struct ican3_dev *mod)
1285{
1286 struct sk_buff *skb = skb_dequeue(&mod->echoq);
1287 struct can_frame *cf;
1288 u8 dlc;
1289
1290 /* this should never trigger unless there is a driver bug */
1291 if (!skb) {
1292 netdev_err(mod->ndev, "BUG: echo skb not occupied\n");
1293 return 0;
1294 }
1295
1296 cf = (struct can_frame *)skb->data;
1297 dlc = cf->can_dlc;
1298
1299 /* check flag whether this packet has to be looped back */
1300 if (skb->pkt_type != PACKET_LOOPBACK) {
1301 kfree_skb(skb);
1302 return dlc;
1303 }
1304
1305 skb->protocol = htons(ETH_P_CAN);
1306 skb->pkt_type = PACKET_BROADCAST;
1307 skb->ip_summed = CHECKSUM_UNNECESSARY;
1308 skb->dev = mod->ndev;
1309 netif_receive_skb(skb);
1310 return dlc;
1311}
1312
1313/*
1314 * Compare an skb with an existing echo skb
1315 *
1316 * This function will be used on devices which have a hardware loopback.
1317 * On these devices, this function can be used to compare a received skb
1318 * with the saved echo skbs so that the hardware echo skb can be dropped.
1319 *
1320 * Returns true if the skb's are identical, false otherwise.
1321 */
1322static bool ican3_echo_skb_matches(struct ican3_dev *mod, struct sk_buff *skb)
1323{
1324 struct can_frame *cf = (struct can_frame *)skb->data;
1325 struct sk_buff *echo_skb = skb_peek(&mod->echoq);
1326 struct can_frame *echo_cf;
1327
1328 if (!echo_skb)
1329 return false;
1330
1331 echo_cf = (struct can_frame *)echo_skb->data;
1332 if (cf->can_id != echo_cf->can_id)
1333 return false;
1334
1335 if (cf->can_dlc != echo_cf->can_dlc)
1336 return false;
1337
1338 return memcmp(cf->data, echo_cf->data, cf->can_dlc) == 0;
1339}
1340
1341/*
1342 * Check that there is room in the TX ring to transmit another skb
1343 *
1344 * LOCKING: must hold mod->lock
1345 */
1346static bool ican3_txok(struct ican3_dev *mod)
1347{
1348 struct ican3_fast_desc __iomem *desc;
1349 u8 control;
1350
1351 /* check that we have echo queue space */
1352 if (skb_queue_len(&mod->echoq) >= ICAN3_TX_BUFFERS)
1353 return false;
1354
1355 /* copy the control bits of the descriptor */
1356 ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
1357 desc = mod->dpm + ((mod->fasttx_num % 16) * sizeof(*desc));
1358 control = ioread8(&desc->control);
1359
1360 /* if the control bits are not valid, then we have no more space */
1361 if (!(control & DESC_VALID))
1362 return false;
1363
1364 return true;
1365}
1366
1367/*
1368 * Receive one CAN frame from the hardware
1369 *
1370 * CONTEXT: must be called from user context
1371 */
1372static int ican3_recv_skb(struct ican3_dev *mod)
1373{
1374 struct net_device *ndev = mod->ndev;
1375 struct net_device_stats *stats = &ndev->stats;
1376 struct ican3_fast_desc desc;
1377 void __iomem *desc_addr;
1378 struct can_frame *cf;
1379 struct sk_buff *skb;
1380 unsigned long flags;
1381
1382 spin_lock_irqsave(&mod->lock, flags);
1383
1384 /* copy the whole descriptor */
1385 ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
1386 desc_addr = mod->dpm + ((mod->fastrx_num % 16) * sizeof(desc));
1387 memcpy_fromio(&desc, desc_addr, sizeof(desc));
1388
1389 spin_unlock_irqrestore(&mod->lock, flags);
1390
1391 /* check that we actually have a CAN frame */
1392 if (!(desc.control & DESC_VALID))
1393 return -ENOBUFS;
1394
1395 /* allocate an skb */
1396 skb = alloc_can_skb(ndev, &cf);
1397 if (unlikely(skb == NULL)) {
1398 stats->rx_dropped++;
1399 goto err_noalloc;
1400 }
1401
1402 /* convert the ICAN3 frame into Linux CAN format */
1403 ican3_to_can_frame(mod, &desc, cf);
1404
1405 /*
1406 * If this is an ECHO frame received from the hardware loopback
1407 * feature, use the skb saved in the ECHO stack instead. This allows
1408 * the Linux CAN core to support CAN_RAW_RECV_OWN_MSGS correctly.
1409 *
1410 * Since this is a confirmation of a successfully transmitted packet
1411 * sent from this host, update the transmit statistics.
1412 *
1413 * Also, the netdevice queue needs to be allowed to send packets again.
1414 */
1415 if (ican3_echo_skb_matches(mod, skb)) {
1416 stats->tx_packets++;
1417 stats->tx_bytes += ican3_get_echo_skb(mod);
1418 kfree_skb(skb);
1419 goto err_noalloc;
1420 }
1421
1422 /* update statistics, receive the skb */
1423 stats->rx_packets++;
1424 stats->rx_bytes += cf->can_dlc;
1425 netif_receive_skb(skb);
1426
1427err_noalloc:
1428 /* toggle the valid bit and return the descriptor to the ring */
1429 desc.control ^= DESC_VALID;
1430
1431 spin_lock_irqsave(&mod->lock, flags);
1432
1433 ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
1434 memcpy_toio(desc_addr, &desc, 1);
1435
1436 /* update the next buffer pointer */
1437 mod->fastrx_num = (desc.control & DESC_WRAP) ? 0
1438 : (mod->fastrx_num + 1);
1439
1440 /* there are still more buffers to process */
1441 spin_unlock_irqrestore(&mod->lock, flags);
1442 return 0;
1443}
1444
1445static int ican3_napi(struct napi_struct *napi, int budget)
1446{
1447 struct ican3_dev *mod = container_of(napi, struct ican3_dev, napi);
1448 unsigned long flags;
1449 int received = 0;
1450 int ret;
1451
1452 /* process all communication messages */
1453 while (true) {
1454 struct ican3_msg uninitialized_var(msg);
1455 ret = ican3_recv_msg(mod, &msg);
1456 if (ret)
1457 break;
1458
1459 ican3_handle_message(mod, &msg);
1460 }
1461
1462 /* process all CAN frames from the fast interface */
1463 while (received < budget) {
1464 ret = ican3_recv_skb(mod);
1465 if (ret)
1466 break;
1467
1468 received++;
1469 }
1470
1471 /* We have processed all packets that the adapter had, but it
1472 * was less than our budget, stop polling */
1473 if (received < budget)
1474 napi_complete_done(napi, received);
1475
1476 spin_lock_irqsave(&mod->lock, flags);
1477
1478 /* Wake up the transmit queue if necessary */
1479 if (netif_queue_stopped(mod->ndev) && ican3_txok(mod))
1480 netif_wake_queue(mod->ndev);
1481
1482 spin_unlock_irqrestore(&mod->lock, flags);
1483
1484 /* re-enable interrupt generation */
1485 iowrite8(1 << mod->num, &mod->ctrl->int_enable);
1486 return received;
1487}
1488
1489static irqreturn_t ican3_irq(int irq, void *dev_id)
1490{
1491 struct ican3_dev *mod = dev_id;
1492 u8 stat;
1493
1494 /*
1495 * The interrupt status register on this device reports interrupts
1496 * as zeroes instead of using ones like most other devices
1497 */
1498 stat = ioread8(&mod->ctrl->int_disable) & (1 << mod->num);
1499 if (stat == (1 << mod->num))
1500 return IRQ_NONE;
1501
1502 /* clear the MODULbus interrupt from the microcontroller */
1503 ioread8(&mod->dpmctrl->interrupt);
1504
1505 /* disable interrupt generation, schedule the NAPI poller */
1506 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
1507 napi_schedule(&mod->napi);
1508 return IRQ_HANDLED;
1509}
1510
1511/*
1512 * Firmware reset, startup, and shutdown
1513 */
1514
1515/*
1516 * Reset an ICAN module to its power-on state
1517 *
1518 * CONTEXT: no network device registered
1519 */
1520static int ican3_reset_module(struct ican3_dev *mod)
1521{
1522 unsigned long start;
1523 u8 runold, runnew;
1524
1525 /* disable interrupts so no more work is scheduled */
1526 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
1527
1528 /* the first unallocated page in the DPM is #9 */
1529 mod->free_page = DPM_FREE_START;
1530
1531 ican3_set_page(mod, QUEUE_OLD_CONTROL);
1532 runold = ioread8(mod->dpm + TARGET_RUNNING);
1533
1534 /* reset the module */
1535 iowrite8(0x00, &mod->dpmctrl->hwreset);
1536
1537 /* wait until the module has finished resetting and is running */
1538 start = jiffies;
1539 do {
1540 ican3_set_page(mod, QUEUE_OLD_CONTROL);
1541 runnew = ioread8(mod->dpm + TARGET_RUNNING);
1542 if (runnew == (runold ^ 0xff))
1543 return 0;
1544
1545 msleep(10);
1546 } while (time_before(jiffies, start + HZ / 2));
1547
1548 netdev_err(mod->ndev, "failed to reset CAN module\n");
1549 return -ETIMEDOUT;
1550}
1551
1552static void ican3_shutdown_module(struct ican3_dev *mod)
1553{
1554 ican3_msg_disconnect(mod);
1555 ican3_reset_module(mod);
1556}
1557
1558/*
1559 * Startup an ICAN module, bringing it into fast mode
1560 */
1561static int ican3_startup_module(struct ican3_dev *mod)
1562{
1563 int ret;
1564
1565 ret = ican3_reset_module(mod);
1566 if (ret) {
1567 netdev_err(mod->ndev, "unable to reset module\n");
1568 return ret;
1569 }
1570
1571 /* detect firmware */
1572 memcpy_fromio(mod->fwinfo, mod->dpm + FIRMWARE_STAMP, sizeof(mod->fwinfo) - 1);
1573 if (strncmp(mod->fwinfo, "JANZ-ICAN3", 10)) {
1574 netdev_err(mod->ndev, "ICAN3 not detected (found %s)\n", mod->fwinfo);
1575 return -ENODEV;
1576 }
1577 if (strstr(mod->fwinfo, "CAL/CANopen"))
1578 mod->fwtype = ICAN3_FWTYPE_CAL_CANOPEN;
1579 else
1580 mod->fwtype = ICAN3_FWTYPE_ICANOS;
1581
1582 /* re-enable interrupts so we can send messages */
1583 iowrite8(1 << mod->num, &mod->ctrl->int_enable);
1584
1585 ret = ican3_msg_connect(mod);
1586 if (ret) {
1587 netdev_err(mod->ndev, "unable to connect to module\n");
1588 return ret;
1589 }
1590
1591 ican3_init_new_host_interface(mod);
1592 ret = ican3_msg_newhostif(mod);
1593 if (ret) {
1594 netdev_err(mod->ndev, "unable to switch to new-style interface\n");
1595 return ret;
1596 }
1597
1598 /* default to "termination on" */
1599 ret = ican3_set_termination(mod, true);
1600 if (ret) {
1601 netdev_err(mod->ndev, "unable to enable termination\n");
1602 return ret;
1603 }
1604
1605 /* default to "bus errors enabled" */
1606 ret = ican3_set_buserror(mod, 1);
1607 if (ret) {
1608 netdev_err(mod->ndev, "unable to set bus-error\n");
1609 return ret;
1610 }
1611
1612 ican3_init_fast_host_interface(mod);
1613 ret = ican3_msg_fasthostif(mod);
1614 if (ret) {
1615 netdev_err(mod->ndev, "unable to switch to fast host interface\n");
1616 return ret;
1617 }
1618
1619 ret = ican3_set_id_filter(mod, true);
1620 if (ret) {
1621 netdev_err(mod->ndev, "unable to set acceptance filter\n");
1622 return ret;
1623 }
1624
1625 return 0;
1626}
1627
1628/*
1629 * CAN Network Device
1630 */
1631
1632static int ican3_open(struct net_device *ndev)
1633{
1634 struct ican3_dev *mod = netdev_priv(ndev);
1635 int ret;
1636
1637 /* open the CAN layer */
1638 ret = open_candev(ndev);
1639 if (ret) {
1640 netdev_err(mod->ndev, "unable to start CAN layer\n");
1641 return ret;
1642 }
1643
1644 /* bring the bus online */
1645 ret = ican3_set_bus_state(mod, true);
1646 if (ret) {
1647 netdev_err(mod->ndev, "unable to set bus-on\n");
1648 close_candev(ndev);
1649 return ret;
1650 }
1651
1652 /* start up the network device */
1653 mod->can.state = CAN_STATE_ERROR_ACTIVE;
1654 netif_start_queue(ndev);
1655
1656 return 0;
1657}
1658
1659static int ican3_stop(struct net_device *ndev)
1660{
1661 struct ican3_dev *mod = netdev_priv(ndev);
1662 int ret;
1663
1664 /* stop the network device xmit routine */
1665 netif_stop_queue(ndev);
1666 mod->can.state = CAN_STATE_STOPPED;
1667
1668 /* bring the bus offline, stop receiving packets */
1669 ret = ican3_set_bus_state(mod, false);
1670 if (ret) {
1671 netdev_err(mod->ndev, "unable to set bus-off\n");
1672 return ret;
1673 }
1674
1675 /* drop all outstanding echo skbs */
1676 skb_queue_purge(&mod->echoq);
1677
1678 /* close the CAN layer */
1679 close_candev(ndev);
1680 return 0;
1681}
1682
1683static netdev_tx_t ican3_xmit(struct sk_buff *skb, struct net_device *ndev)
1684{
1685 struct ican3_dev *mod = netdev_priv(ndev);
1686 struct can_frame *cf = (struct can_frame *)skb->data;
1687 struct ican3_fast_desc desc;
1688 void __iomem *desc_addr;
1689 unsigned long flags;
1690
1691 if (can_dropped_invalid_skb(ndev, skb))
1692 return NETDEV_TX_OK;
1693
1694 spin_lock_irqsave(&mod->lock, flags);
1695
1696 /* check that we can actually transmit */
1697 if (!ican3_txok(mod)) {
1698 netdev_err(mod->ndev, "BUG: no free descriptors\n");
1699 spin_unlock_irqrestore(&mod->lock, flags);
1700 return NETDEV_TX_BUSY;
1701 }
1702
1703 /* copy the control bits of the descriptor */
1704 ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
1705 desc_addr = mod->dpm + ((mod->fasttx_num % 16) * sizeof(desc));
1706 memset(&desc, 0, sizeof(desc));
1707 memcpy_fromio(&desc, desc_addr, 1);
1708
1709 /* convert the Linux CAN frame into ICAN3 format */
1710 can_frame_to_ican3(mod, cf, &desc);
1711
1712 /*
1713 * This hardware doesn't have TX-done notifications, so we'll try and
1714 * emulate it the best we can using ECHO skbs. Add the skb to the ECHO
1715 * stack. Upon packet reception, check if the ECHO skb and received
1716 * skb match, and use that to wake the queue.
1717 */
1718 ican3_put_echo_skb(mod, skb);
1719
1720 /*
1721 * the programming manual says that you must set the IVALID bit, then
1722 * interrupt, then set the valid bit. Quite weird, but it seems to be
1723 * required for this to work
1724 */
1725 desc.control |= DESC_IVALID;
1726 memcpy_toio(desc_addr, &desc, sizeof(desc));
1727
1728 /* generate a MODULbus interrupt to the microcontroller */
1729 iowrite8(0x01, &mod->dpmctrl->interrupt);
1730
1731 desc.control ^= DESC_VALID;
1732 memcpy_toio(desc_addr, &desc, sizeof(desc));
1733
1734 /* update the next buffer pointer */
1735 mod->fasttx_num = (desc.control & DESC_WRAP) ? 0
1736 : (mod->fasttx_num + 1);
1737
1738 /* if there is no free descriptor space, stop the transmit queue */
1739 if (!ican3_txok(mod))
1740 netif_stop_queue(ndev);
1741
1742 spin_unlock_irqrestore(&mod->lock, flags);
1743 return NETDEV_TX_OK;
1744}
1745
1746static const struct net_device_ops ican3_netdev_ops = {
1747 .ndo_open = ican3_open,
1748 .ndo_stop = ican3_stop,
1749 .ndo_start_xmit = ican3_xmit,
1750 .ndo_change_mtu = can_change_mtu,
1751};
1752
1753/*
1754 * Low-level CAN Device
1755 */
1756
1757/* This structure was stolen from drivers/net/can/sja1000/sja1000.c */
1758static const struct can_bittiming_const ican3_bittiming_const = {
1759 .name = DRV_NAME,
1760 .tseg1_min = 1,
1761 .tseg1_max = 16,
1762 .tseg2_min = 1,
1763 .tseg2_max = 8,
1764 .sjw_max = 4,
1765 .brp_min = 1,
1766 .brp_max = 64,
1767 .brp_inc = 1,
1768};
1769
1770static int ican3_set_mode(struct net_device *ndev, enum can_mode mode)
1771{
1772 struct ican3_dev *mod = netdev_priv(ndev);
1773 int ret;
1774
1775 if (mode != CAN_MODE_START)
1776 return -ENOTSUPP;
1777
1778 /* bring the bus online */
1779 ret = ican3_set_bus_state(mod, true);
1780 if (ret) {
1781 netdev_err(ndev, "unable to set bus-on\n");
1782 return ret;
1783 }
1784
1785 /* start up the network device */
1786 mod->can.state = CAN_STATE_ERROR_ACTIVE;
1787
1788 if (netif_queue_stopped(ndev))
1789 netif_wake_queue(ndev);
1790
1791 return 0;
1792}
1793
1794static int ican3_get_berr_counter(const struct net_device *ndev,
1795 struct can_berr_counter *bec)
1796{
1797 struct ican3_dev *mod = netdev_priv(ndev);
1798 int ret;
1799
1800 ret = ican3_send_inquiry(mod, INQUIRY_STATUS);
1801 if (ret)
1802 return ret;
1803
1804 if (!wait_for_completion_timeout(&mod->buserror_comp, HZ)) {
1805 netdev_info(mod->ndev, "%s timed out\n", __func__);
1806 return -ETIMEDOUT;
1807 }
1808
1809 bec->rxerr = mod->bec.rxerr;
1810 bec->txerr = mod->bec.txerr;
1811 return 0;
1812}
1813
1814/*
1815 * Sysfs Attributes
1816 */
1817
1818static ssize_t ican3_sysfs_show_term(struct device *dev,
1819 struct device_attribute *attr,
1820 char *buf)
1821{
1822 struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
1823 int ret;
1824
1825 ret = ican3_send_inquiry(mod, INQUIRY_TERMINATION);
1826 if (ret)
1827 return ret;
1828
1829 if (!wait_for_completion_timeout(&mod->termination_comp, HZ)) {
1830 netdev_info(mod->ndev, "%s timed out\n", __func__);
1831 return -ETIMEDOUT;
1832 }
1833
1834 return snprintf(buf, PAGE_SIZE, "%u\n", mod->termination_enabled);
1835}
1836
1837static ssize_t ican3_sysfs_set_term(struct device *dev,
1838 struct device_attribute *attr,
1839 const char *buf, size_t count)
1840{
1841 struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
1842 unsigned long enable;
1843 int ret;
1844
1845 if (kstrtoul(buf, 0, &enable))
1846 return -EINVAL;
1847
1848 ret = ican3_set_termination(mod, enable);
1849 if (ret)
1850 return ret;
1851
1852 return count;
1853}
1854
1855static ssize_t ican3_sysfs_show_fwinfo(struct device *dev,
1856 struct device_attribute *attr,
1857 char *buf)
1858{
1859 struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
1860
1861 return scnprintf(buf, PAGE_SIZE, "%s\n", mod->fwinfo);
1862}
1863
1864static DEVICE_ATTR(termination, 0644, ican3_sysfs_show_term,
1865 ican3_sysfs_set_term);
1866static DEVICE_ATTR(fwinfo, 0444, ican3_sysfs_show_fwinfo, NULL);
1867
1868static struct attribute *ican3_sysfs_attrs[] = {
1869 &dev_attr_termination.attr,
1870 &dev_attr_fwinfo.attr,
1871 NULL,
1872};
1873
1874static const struct attribute_group ican3_sysfs_attr_group = {
1875 .attrs = ican3_sysfs_attrs,
1876};
1877
1878/*
1879 * PCI Subsystem
1880 */
1881
1882static int ican3_probe(struct platform_device *pdev)
1883{
1884 struct janz_platform_data *pdata;
1885 struct net_device *ndev;
1886 struct ican3_dev *mod;
1887 struct resource *res;
1888 struct device *dev;
1889 int ret;
1890
1891 pdata = dev_get_platdata(&pdev->dev);
1892 if (!pdata)
1893 return -ENXIO;
1894
1895 dev_dbg(&pdev->dev, "probe: module number %d\n", pdata->modno);
1896
1897 /* save the struct device for printing */
1898 dev = &pdev->dev;
1899
1900 /* allocate the CAN device and private data */
1901 ndev = alloc_candev(sizeof(*mod), 0);
1902 if (!ndev) {
1903 dev_err(dev, "unable to allocate CANdev\n");
1904 ret = -ENOMEM;
1905 goto out_return;
1906 }
1907
1908 platform_set_drvdata(pdev, ndev);
1909 mod = netdev_priv(ndev);
1910 mod->ndev = ndev;
1911 mod->num = pdata->modno;
1912 netif_napi_add(ndev, &mod->napi, ican3_napi, ICAN3_RX_BUFFERS);
1913 skb_queue_head_init(&mod->echoq);
1914 spin_lock_init(&mod->lock);
1915 init_completion(&mod->termination_comp);
1916 init_completion(&mod->buserror_comp);
1917
1918 /* setup device-specific sysfs attributes */
1919 ndev->sysfs_groups[0] = &ican3_sysfs_attr_group;
1920
1921 /* the first unallocated page in the DPM is 9 */
1922 mod->free_page = DPM_FREE_START;
1923
1924 ndev->netdev_ops = &ican3_netdev_ops;
1925 ndev->flags |= IFF_ECHO;
1926 SET_NETDEV_DEV(ndev, &pdev->dev);
1927
1928 mod->can.clock.freq = ICAN3_CAN_CLOCK;
1929 mod->can.bittiming_const = &ican3_bittiming_const;
1930 mod->can.do_set_mode = ican3_set_mode;
1931 mod->can.do_get_berr_counter = ican3_get_berr_counter;
1932 mod->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES
1933 | CAN_CTRLMODE_BERR_REPORTING
1934 | CAN_CTRLMODE_ONE_SHOT;
1935
1936 /* find our IRQ number */
1937 mod->irq = platform_get_irq(pdev, 0);
1938 if (mod->irq < 0) {
1939 ret = -ENODEV;
1940 goto out_free_ndev;
1941 }
1942
1943 ndev->irq = mod->irq;
1944
1945 /* get access to the MODULbus registers for this module */
1946 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1947 if (!res) {
1948 dev_err(dev, "MODULbus registers not found\n");
1949 ret = -ENODEV;
1950 goto out_free_ndev;
1951 }
1952
1953 mod->dpm = ioremap(res->start, resource_size(res));
1954 if (!mod->dpm) {
1955 dev_err(dev, "MODULbus registers not ioremap\n");
1956 ret = -ENOMEM;
1957 goto out_free_ndev;
1958 }
1959
1960 mod->dpmctrl = mod->dpm + DPM_PAGE_SIZE;
1961
1962 /* get access to the control registers for this module */
1963 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1964 if (!res) {
1965 dev_err(dev, "CONTROL registers not found\n");
1966 ret = -ENODEV;
1967 goto out_iounmap_dpm;
1968 }
1969
1970 mod->ctrl = ioremap(res->start, resource_size(res));
1971 if (!mod->ctrl) {
1972 dev_err(dev, "CONTROL registers not ioremap\n");
1973 ret = -ENOMEM;
1974 goto out_iounmap_dpm;
1975 }
1976
1977 /* disable our IRQ, then hookup the IRQ handler */
1978 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
1979 ret = request_irq(mod->irq, ican3_irq, IRQF_SHARED, DRV_NAME, mod);
1980 if (ret) {
1981 dev_err(dev, "unable to request IRQ\n");
1982 goto out_iounmap_ctrl;
1983 }
1984
1985 /* reset and initialize the CAN controller into fast mode */
1986 napi_enable(&mod->napi);
1987 ret = ican3_startup_module(mod);
1988 if (ret) {
1989 dev_err(dev, "%s: unable to start CANdev\n", __func__);
1990 goto out_free_irq;
1991 }
1992
1993 /* register with the Linux CAN layer */
1994 ret = register_candev(ndev);
1995 if (ret) {
1996 dev_err(dev, "%s: unable to register CANdev\n", __func__);
1997 goto out_free_irq;
1998 }
1999
2000 netdev_info(mod->ndev, "module %d: registered CAN device\n", pdata->modno);
2001 return 0;
2002
2003out_free_irq:
2004 napi_disable(&mod->napi);
2005 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
2006 free_irq(mod->irq, mod);
2007out_iounmap_ctrl:
2008 iounmap(mod->ctrl);
2009out_iounmap_dpm:
2010 iounmap(mod->dpm);
2011out_free_ndev:
2012 free_candev(ndev);
2013out_return:
2014 return ret;
2015}
2016
2017static int ican3_remove(struct platform_device *pdev)
2018{
2019 struct net_device *ndev = platform_get_drvdata(pdev);
2020 struct ican3_dev *mod = netdev_priv(ndev);
2021
2022 /* unregister the netdevice, stop interrupts */
2023 unregister_netdev(ndev);
2024 napi_disable(&mod->napi);
2025 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
2026 free_irq(mod->irq, mod);
2027
2028 /* put the module into reset */
2029 ican3_shutdown_module(mod);
2030
2031 /* unmap all registers */
2032 iounmap(mod->ctrl);
2033 iounmap(mod->dpm);
2034
2035 free_candev(ndev);
2036
2037 return 0;
2038}
2039
2040static struct platform_driver ican3_driver = {
2041 .driver = {
2042 .name = DRV_NAME,
2043 },
2044 .probe = ican3_probe,
2045 .remove = ican3_remove,
2046};
2047
2048module_platform_driver(ican3_driver);
2049
2050MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
2051MODULE_DESCRIPTION("Janz MODULbus VMOD-ICAN3 Driver");
2052MODULE_LICENSE("GPL");
2053MODULE_ALIAS("platform:janz-ican3");