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 */
184 enum 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 */
193 struct 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
213 struct 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
272 struct ican3_msg {
273 u8 control;
274 u8 spec;
275 __le16 len;
276 u8 data[252];
277 };
278
279 struct ican3_new_desc {
280 u8 control;
281 u8 pointer;
282 };
283
284 struct ican3_fast_desc {
285 u8 control;
286 u8 command;
287 u8 data[14];
288 };
289
290 /* write to the window basic address register */
ican3_set_page(struct ican3_dev * mod,unsigned int page)291 static 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 */
ican3_old_recv_msg(struct ican3_dev * mod,struct ican3_msg * msg)308 static 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 */
ican3_old_send_msg(struct ican3_dev * mod,struct ican3_msg * msg)353 static 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
ican3_init_new_host_interface(struct ican3_dev * mod)390 static 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
ican3_init_fast_host_interface(struct ican3_dev * mod)469 static 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 */
ican3_new_send_msg(struct ican3_dev * mod,struct ican3_msg * msg)557 static 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 */
ican3_new_recv_msg(struct ican3_dev * mod,struct ican3_msg * msg)588 static 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
ican3_send_msg(struct ican3_dev * mod,struct ican3_msg * msg)620 static 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
ican3_recv_msg(struct ican3_dev * mod,struct ican3_msg * msg)636 static 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
ican3_msg_connect(struct ican3_dev * mod)656 static 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
ican3_msg_disconnect(struct ican3_dev * mod)667 static 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
ican3_msg_newhostif(struct ican3_dev * mod)678 static 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
ican3_msg_fasthostif(struct ican3_dev * mod)699 static 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 */
ican3_set_id_filter(struct ican3_dev * mod,bool accept)732 static 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 */
ican3_set_bus_state(struct ican3_dev * mod,bool on)776 static 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
ican3_set_termination(struct ican3_dev * mod,bool on)855 static 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
ican3_send_inquiry(struct ican3_dev * mod,u8 subspec)868 static 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
ican3_set_buserror(struct ican3_dev * mod,u8 quota)881 static 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
ican3_to_can_frame(struct ican3_dev * mod,struct ican3_fast_desc * desc,struct can_frame * cf)909 static 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
can_frame_to_ican3(struct ican3_dev * mod,struct can_frame * cf,struct ican3_fast_desc * desc)941 static 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 */
ican3_handle_idvers(struct ican3_dev * mod,struct ican3_msg * msg)985 static 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
ican3_handle_msglost(struct ican3_dev * mod,struct ican3_msg * msg)990 static 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 */
ican3_handle_cevtind(struct ican3_dev * mod,struct ican3_msg * msg)1032 static 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
ican3_handle_inquiry(struct ican3_dev * mod,struct ican3_msg * msg)1178 static 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 */
ican3_handle_nmtsind(struct ican3_dev * mod,struct ican3_msg * msg)1198 static 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
ican3_handle_unknown_message(struct ican3_dev * mod,struct ican3_msg * msg)1232 static 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 */
ican3_handle_message(struct ican3_dev * mod,struct ican3_msg * msg)1242 static 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 */
ican3_put_echo_skb(struct ican3_dev * mod,struct sk_buff * skb)1274 static 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
ican3_get_echo_skb(struct ican3_dev * mod)1284 static 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 */
ican3_echo_skb_matches(struct ican3_dev * mod,struct sk_buff * skb)1322 static 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 */
ican3_txok(struct ican3_dev * mod)1346 static 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 */
ican3_recv_skb(struct ican3_dev * mod)1372 static 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
1427 err_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
ican3_napi(struct napi_struct * napi,int budget)1445 static 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 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
ican3_irq(int irq,void * dev_id)1489 static 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 */
ican3_reset_module(struct ican3_dev * mod)1520 static 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
ican3_shutdown_module(struct ican3_dev * mod)1552 static 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 */
ican3_startup_module(struct ican3_dev * mod)1561 static 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
ican3_open(struct net_device * ndev)1632 static 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
ican3_stop(struct net_device * ndev)1659 static 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
ican3_xmit(struct sk_buff * skb,struct net_device * ndev)1683 static 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
1746 static 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 */
1758 static 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
ican3_set_mode(struct net_device * ndev,enum can_mode mode)1770 static 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
ican3_get_berr_counter(const struct net_device * ndev,struct can_berr_counter * bec)1794 static 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
ican3_sysfs_show_term(struct device * dev,struct device_attribute * attr,char * buf)1818 static 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
ican3_sysfs_set_term(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1837 static 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
ican3_sysfs_show_fwinfo(struct device * dev,struct device_attribute * attr,char * buf)1855 static 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
1864 static DEVICE_ATTR(termination, 0644, ican3_sysfs_show_term,
1865 ican3_sysfs_set_term);
1866 static DEVICE_ATTR(fwinfo, 0444, ican3_sysfs_show_fwinfo, NULL);
1867
1868 static struct attribute *ican3_sysfs_attrs[] = {
1869 &dev_attr_termination.attr,
1870 &dev_attr_fwinfo.attr,
1871 NULL,
1872 };
1873
1874 static const struct attribute_group ican3_sysfs_attr_group = {
1875 .attrs = ican3_sysfs_attrs,
1876 };
1877
1878 /*
1879 * PCI Subsystem
1880 */
1881
ican3_probe(struct platform_device * pdev)1882 static 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
2003 out_free_irq:
2004 napi_disable(&mod->napi);
2005 iowrite8(1 << mod->num, &mod->ctrl->int_disable);
2006 free_irq(mod->irq, mod);
2007 out_iounmap_ctrl:
2008 iounmap(mod->ctrl);
2009 out_iounmap_dpm:
2010 iounmap(mod->dpm);
2011 out_free_ndev:
2012 free_candev(ndev);
2013 out_return:
2014 return ret;
2015 }
2016
ican3_remove(struct platform_device * pdev)2017 static 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
2040 static struct platform_driver ican3_driver = {
2041 .driver = {
2042 .name = DRV_NAME,
2043 },
2044 .probe = ican3_probe,
2045 .remove = ican3_remove,
2046 };
2047
2048 module_platform_driver(ican3_driver);
2049
2050 MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
2051 MODULE_DESCRIPTION("Janz MODULbus VMOD-ICAN3 Driver");
2052 MODULE_LICENSE("GPL");
2053 MODULE_ALIAS("platform:janz-ican3");
2054