1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Core driver for the CC770 and AN82527 CAN controllers
4 *
5 * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com>
6 */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/types.h>
15 #include <linux/fcntl.h>
16 #include <linux/interrupt.h>
17 #include <linux/ptrace.h>
18 #include <linux/string.h>
19 #include <linux/errno.h>
20 #include <linux/ethtool.h>
21 #include <linux/netdevice.h>
22 #include <linux/if_arp.h>
23 #include <linux/if_ether.h>
24 #include <linux/skbuff.h>
25 #include <linux/delay.h>
26
27 #include <linux/can.h>
28 #include <linux/can/dev.h>
29 #include <linux/can/error.h>
30 #include <linux/can/platform/cc770.h>
31
32 #include "cc770.h"
33
34 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
35 MODULE_LICENSE("GPL v2");
36 MODULE_DESCRIPTION(KBUILD_MODNAME "CAN netdevice driver");
37
38 /*
39 * The CC770 is a CAN controller from Bosch, which is 100% compatible
40 * with the AN82527 from Intel, but with "bugs" being fixed and some
41 * additional functionality, mainly:
42 *
43 * 1. RX and TX error counters are readable.
44 * 2. Support of silent (listen-only) mode.
45 * 3. Message object 15 can receive all types of frames, also RTR and EFF.
46 *
47 * Details are available from Bosch's "CC770_Product_Info_2007-01.pdf",
48 * which explains in detail the compatibility between the CC770 and the
49 * 82527. This driver use the additional functionality 3. on real CC770
50 * devices. Unfortunately, the CC770 does still not store the message
51 * identifier of received remote transmission request frames and
52 * therefore it's set to 0.
53 *
54 * The message objects 1..14 can be used for TX and RX while the message
55 * objects 15 is optimized for RX. It has a shadow register for reliable
56 * data reception under heavy bus load. Therefore it makes sense to use
57 * this message object for the needed use case. The frame type (EFF/SFF)
58 * for the message object 15 can be defined via kernel module parameter
59 * "msgobj15_eff". If not equal 0, it will receive 29-bit EFF frames,
60 * otherwise 11 bit SFF messages.
61 */
62 static int msgobj15_eff;
63 module_param(msgobj15_eff, int, 0444);
64 MODULE_PARM_DESC(msgobj15_eff, "Extended 29-bit frames for message object 15 "
65 "(default: 11-bit standard frames)");
66
67 static int i82527_compat;
68 module_param(i82527_compat, int, 0444);
69 MODULE_PARM_DESC(i82527_compat, "Strict Intel 82527 compatibility mode "
70 "without using additional functions");
71
72 /*
73 * This driver uses the last 5 message objects 11..15. The definitions
74 * and structure below allows to configure and assign them to the real
75 * message object.
76 */
77 static unsigned char cc770_obj_flags[CC770_OBJ_MAX] = {
78 [CC770_OBJ_RX0] = CC770_OBJ_FLAG_RX,
79 [CC770_OBJ_RX1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_EFF,
80 [CC770_OBJ_RX_RTR0] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR,
81 [CC770_OBJ_RX_RTR1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR |
82 CC770_OBJ_FLAG_EFF,
83 [CC770_OBJ_TX] = 0,
84 };
85
86 static const struct can_bittiming_const cc770_bittiming_const = {
87 .name = KBUILD_MODNAME,
88 .tseg1_min = 1,
89 .tseg1_max = 16,
90 .tseg2_min = 1,
91 .tseg2_max = 8,
92 .sjw_max = 4,
93 .brp_min = 1,
94 .brp_max = 64,
95 .brp_inc = 1,
96 };
97
intid2obj(unsigned int intid)98 static inline int intid2obj(unsigned int intid)
99 {
100 if (intid == 2)
101 return 0;
102 else
103 return MSGOBJ_LAST + 2 - intid;
104 }
105
enable_all_objs(const struct net_device * dev)106 static void enable_all_objs(const struct net_device *dev)
107 {
108 struct cc770_priv *priv = netdev_priv(dev);
109 u8 msgcfg;
110 unsigned char obj_flags;
111 unsigned int o, mo;
112
113 for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) {
114 obj_flags = priv->obj_flags[o];
115 mo = obj2msgobj(o);
116
117 if (obj_flags & CC770_OBJ_FLAG_RX) {
118 /*
119 * We don't need extra objects for RTR and EFF if
120 * the additional CC770 functions are enabled.
121 */
122 if (priv->control_normal_mode & CTRL_EAF) {
123 if (o > 0)
124 continue;
125 netdev_dbg(dev, "Message object %d for "
126 "RX data, RTR, SFF and EFF\n", mo);
127 } else {
128 netdev_dbg(dev,
129 "Message object %d for RX %s %s\n",
130 mo, obj_flags & CC770_OBJ_FLAG_RTR ?
131 "RTR" : "data",
132 obj_flags & CC770_OBJ_FLAG_EFF ?
133 "EFF" : "SFF");
134 }
135
136 if (obj_flags & CC770_OBJ_FLAG_EFF)
137 msgcfg = MSGCFG_XTD;
138 else
139 msgcfg = 0;
140 if (obj_flags & CC770_OBJ_FLAG_RTR)
141 msgcfg |= MSGCFG_DIR;
142
143 cc770_write_reg(priv, msgobj[mo].config, msgcfg);
144 cc770_write_reg(priv, msgobj[mo].ctrl0,
145 MSGVAL_SET | TXIE_RES |
146 RXIE_SET | INTPND_RES);
147
148 if (obj_flags & CC770_OBJ_FLAG_RTR)
149 cc770_write_reg(priv, msgobj[mo].ctrl1,
150 NEWDAT_RES | CPUUPD_SET |
151 TXRQST_RES | RMTPND_RES);
152 else
153 cc770_write_reg(priv, msgobj[mo].ctrl1,
154 NEWDAT_RES | MSGLST_RES |
155 TXRQST_RES | RMTPND_RES);
156 } else {
157 netdev_dbg(dev, "Message object %d for "
158 "TX data, RTR, SFF and EFF\n", mo);
159
160 cc770_write_reg(priv, msgobj[mo].ctrl1,
161 RMTPND_RES | TXRQST_RES |
162 CPUUPD_RES | NEWDAT_RES);
163 cc770_write_reg(priv, msgobj[mo].ctrl0,
164 MSGVAL_RES | TXIE_RES |
165 RXIE_RES | INTPND_RES);
166 }
167 }
168 }
169
disable_all_objs(const struct cc770_priv * priv)170 static void disable_all_objs(const struct cc770_priv *priv)
171 {
172 int o, mo;
173
174 for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) {
175 mo = obj2msgobj(o);
176
177 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX) {
178 if (o > 0 && priv->control_normal_mode & CTRL_EAF)
179 continue;
180
181 cc770_write_reg(priv, msgobj[mo].ctrl1,
182 NEWDAT_RES | MSGLST_RES |
183 TXRQST_RES | RMTPND_RES);
184 cc770_write_reg(priv, msgobj[mo].ctrl0,
185 MSGVAL_RES | TXIE_RES |
186 RXIE_RES | INTPND_RES);
187 } else {
188 /* Clear message object for send */
189 cc770_write_reg(priv, msgobj[mo].ctrl1,
190 RMTPND_RES | TXRQST_RES |
191 CPUUPD_RES | NEWDAT_RES);
192 cc770_write_reg(priv, msgobj[mo].ctrl0,
193 MSGVAL_RES | TXIE_RES |
194 RXIE_RES | INTPND_RES);
195 }
196 }
197 }
198
set_reset_mode(struct net_device * dev)199 static void set_reset_mode(struct net_device *dev)
200 {
201 struct cc770_priv *priv = netdev_priv(dev);
202
203 /* Enable configuration and puts chip in bus-off, disable interrupts */
204 cc770_write_reg(priv, control, CTRL_CCE | CTRL_INI);
205
206 priv->can.state = CAN_STATE_STOPPED;
207
208 /* Clear interrupts */
209 cc770_read_reg(priv, interrupt);
210
211 /* Clear status register */
212 cc770_write_reg(priv, status, 0);
213
214 /* Disable all used message objects */
215 disable_all_objs(priv);
216 }
217
set_normal_mode(struct net_device * dev)218 static void set_normal_mode(struct net_device *dev)
219 {
220 struct cc770_priv *priv = netdev_priv(dev);
221
222 /* Clear interrupts */
223 cc770_read_reg(priv, interrupt);
224
225 /* Clear status register and pre-set last error code */
226 cc770_write_reg(priv, status, STAT_LEC_MASK);
227
228 /* Enable all used message objects*/
229 enable_all_objs(dev);
230
231 /*
232 * Clear bus-off, interrupts only for errors,
233 * not for status change
234 */
235 cc770_write_reg(priv, control, priv->control_normal_mode);
236
237 priv->can.state = CAN_STATE_ERROR_ACTIVE;
238 }
239
chipset_init(struct cc770_priv * priv)240 static void chipset_init(struct cc770_priv *priv)
241 {
242 int mo, id, data;
243
244 /* Enable configuration and put chip in bus-off, disable interrupts */
245 cc770_write_reg(priv, control, (CTRL_CCE | CTRL_INI));
246
247 /* Set CLKOUT divider and slew rates */
248 cc770_write_reg(priv, clkout, priv->clkout);
249
250 /* Configure CPU interface / CLKOUT enable */
251 cc770_write_reg(priv, cpu_interface, priv->cpu_interface);
252
253 /* Set bus configuration */
254 cc770_write_reg(priv, bus_config, priv->bus_config);
255
256 /* Clear interrupts */
257 cc770_read_reg(priv, interrupt);
258
259 /* Clear status register */
260 cc770_write_reg(priv, status, 0);
261
262 /* Clear and invalidate message objects */
263 for (mo = MSGOBJ_FIRST; mo <= MSGOBJ_LAST; mo++) {
264 cc770_write_reg(priv, msgobj[mo].ctrl0,
265 INTPND_UNC | RXIE_RES |
266 TXIE_RES | MSGVAL_RES);
267 cc770_write_reg(priv, msgobj[mo].ctrl0,
268 INTPND_RES | RXIE_RES |
269 TXIE_RES | MSGVAL_RES);
270 cc770_write_reg(priv, msgobj[mo].ctrl1,
271 NEWDAT_RES | MSGLST_RES |
272 TXRQST_RES | RMTPND_RES);
273 for (data = 0; data < 8; data++)
274 cc770_write_reg(priv, msgobj[mo].data[data], 0);
275 for (id = 0; id < 4; id++)
276 cc770_write_reg(priv, msgobj[mo].id[id], 0);
277 cc770_write_reg(priv, msgobj[mo].config, 0);
278 }
279
280 /* Set all global ID masks to "don't care" */
281 cc770_write_reg(priv, global_mask_std[0], 0);
282 cc770_write_reg(priv, global_mask_std[1], 0);
283 cc770_write_reg(priv, global_mask_ext[0], 0);
284 cc770_write_reg(priv, global_mask_ext[1], 0);
285 cc770_write_reg(priv, global_mask_ext[2], 0);
286 cc770_write_reg(priv, global_mask_ext[3], 0);
287
288 }
289
cc770_probe_chip(struct net_device * dev)290 static int cc770_probe_chip(struct net_device *dev)
291 {
292 struct cc770_priv *priv = netdev_priv(dev);
293
294 /* Enable configuration, put chip in bus-off, disable ints */
295 cc770_write_reg(priv, control, CTRL_CCE | CTRL_EAF | CTRL_INI);
296 /* Configure cpu interface / CLKOUT disable */
297 cc770_write_reg(priv, cpu_interface, priv->cpu_interface);
298
299 /*
300 * Check if hardware reset is still inactive or maybe there
301 * is no chip in this address space
302 */
303 if (cc770_read_reg(priv, cpu_interface) & CPUIF_RST) {
304 netdev_info(dev, "probing @0x%p failed (reset)\n",
305 priv->reg_base);
306 return -ENODEV;
307 }
308
309 /* Write and read back test pattern (some arbitrary values) */
310 cc770_write_reg(priv, msgobj[1].data[1], 0x25);
311 cc770_write_reg(priv, msgobj[2].data[3], 0x52);
312 cc770_write_reg(priv, msgobj[10].data[6], 0xc3);
313 if ((cc770_read_reg(priv, msgobj[1].data[1]) != 0x25) ||
314 (cc770_read_reg(priv, msgobj[2].data[3]) != 0x52) ||
315 (cc770_read_reg(priv, msgobj[10].data[6]) != 0xc3)) {
316 netdev_info(dev, "probing @0x%p failed (pattern)\n",
317 priv->reg_base);
318 return -ENODEV;
319 }
320
321 /* Check if this chip is a CC770 supporting additional functions */
322 if (cc770_read_reg(priv, control) & CTRL_EAF)
323 priv->control_normal_mode |= CTRL_EAF;
324
325 return 0;
326 }
327
cc770_start(struct net_device * dev)328 static void cc770_start(struct net_device *dev)
329 {
330 struct cc770_priv *priv = netdev_priv(dev);
331
332 /* leave reset mode */
333 if (priv->can.state != CAN_STATE_STOPPED)
334 set_reset_mode(dev);
335
336 /* leave reset mode */
337 set_normal_mode(dev);
338 }
339
cc770_set_mode(struct net_device * dev,enum can_mode mode)340 static int cc770_set_mode(struct net_device *dev, enum can_mode mode)
341 {
342 switch (mode) {
343 case CAN_MODE_START:
344 cc770_start(dev);
345 netif_wake_queue(dev);
346 break;
347
348 default:
349 return -EOPNOTSUPP;
350 }
351
352 return 0;
353 }
354
cc770_set_bittiming(struct net_device * dev)355 static int cc770_set_bittiming(struct net_device *dev)
356 {
357 struct cc770_priv *priv = netdev_priv(dev);
358 struct can_bittiming *bt = &priv->can.bittiming;
359 u8 btr0, btr1;
360
361 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
362 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
363 (((bt->phase_seg2 - 1) & 0x7) << 4);
364 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
365 btr1 |= 0x80;
366
367 netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
368
369 cc770_write_reg(priv, bit_timing_0, btr0);
370 cc770_write_reg(priv, bit_timing_1, btr1);
371
372 return 0;
373 }
374
cc770_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)375 static int cc770_get_berr_counter(const struct net_device *dev,
376 struct can_berr_counter *bec)
377 {
378 struct cc770_priv *priv = netdev_priv(dev);
379
380 bec->txerr = cc770_read_reg(priv, tx_error_counter);
381 bec->rxerr = cc770_read_reg(priv, rx_error_counter);
382
383 return 0;
384 }
385
cc770_tx(struct net_device * dev,int mo)386 static void cc770_tx(struct net_device *dev, int mo)
387 {
388 struct cc770_priv *priv = netdev_priv(dev);
389 struct can_frame *cf = (struct can_frame *)priv->tx_skb->data;
390 u8 dlc, rtr;
391 u32 id;
392 int i;
393
394 dlc = cf->len;
395 id = cf->can_id;
396 rtr = cf->can_id & CAN_RTR_FLAG ? 0 : MSGCFG_DIR;
397
398 cc770_write_reg(priv, msgobj[mo].ctrl0,
399 MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES);
400 cc770_write_reg(priv, msgobj[mo].ctrl1,
401 RMTPND_RES | TXRQST_RES | CPUUPD_SET | NEWDAT_RES);
402
403 if (id & CAN_EFF_FLAG) {
404 id &= CAN_EFF_MASK;
405 cc770_write_reg(priv, msgobj[mo].config,
406 (dlc << 4) | rtr | MSGCFG_XTD);
407 cc770_write_reg(priv, msgobj[mo].id[3], id << 3);
408 cc770_write_reg(priv, msgobj[mo].id[2], id >> 5);
409 cc770_write_reg(priv, msgobj[mo].id[1], id >> 13);
410 cc770_write_reg(priv, msgobj[mo].id[0], id >> 21);
411 } else {
412 id &= CAN_SFF_MASK;
413 cc770_write_reg(priv, msgobj[mo].config, (dlc << 4) | rtr);
414 cc770_write_reg(priv, msgobj[mo].id[0], id >> 3);
415 cc770_write_reg(priv, msgobj[mo].id[1], id << 5);
416 }
417
418 for (i = 0; i < dlc; i++)
419 cc770_write_reg(priv, msgobj[mo].data[i], cf->data[i]);
420
421 cc770_write_reg(priv, msgobj[mo].ctrl1,
422 RMTPND_UNC | TXRQST_SET | CPUUPD_RES | NEWDAT_UNC);
423 cc770_write_reg(priv, msgobj[mo].ctrl0,
424 MSGVAL_SET | TXIE_SET | RXIE_SET | INTPND_UNC);
425 }
426
cc770_start_xmit(struct sk_buff * skb,struct net_device * dev)427 static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev)
428 {
429 struct cc770_priv *priv = netdev_priv(dev);
430 unsigned int mo = obj2msgobj(CC770_OBJ_TX);
431
432 if (can_dev_dropped_skb(dev, skb))
433 return NETDEV_TX_OK;
434
435 netif_stop_queue(dev);
436
437 if ((cc770_read_reg(priv,
438 msgobj[mo].ctrl1) & TXRQST_UNC) == TXRQST_SET) {
439 netdev_err(dev, "TX register is still occupied!\n");
440 return NETDEV_TX_BUSY;
441 }
442
443 priv->tx_skb = skb;
444 cc770_tx(dev, mo);
445
446 return NETDEV_TX_OK;
447 }
448
cc770_rx(struct net_device * dev,unsigned int mo,u8 ctrl1)449 static void cc770_rx(struct net_device *dev, unsigned int mo, u8 ctrl1)
450 {
451 struct cc770_priv *priv = netdev_priv(dev);
452 struct net_device_stats *stats = &dev->stats;
453 struct can_frame *cf;
454 struct sk_buff *skb;
455 u8 config;
456 u32 id;
457 int i;
458
459 skb = alloc_can_skb(dev, &cf);
460 if (!skb)
461 return;
462
463 config = cc770_read_reg(priv, msgobj[mo].config);
464
465 if (ctrl1 & RMTPND_SET) {
466 /*
467 * Unfortunately, the chip does not store the real message
468 * identifier of the received remote transmission request
469 * frame. Therefore we set it to 0.
470 */
471 cf->can_id = CAN_RTR_FLAG;
472 if (config & MSGCFG_XTD)
473 cf->can_id |= CAN_EFF_FLAG;
474 cf->len = 0;
475 } else {
476 if (config & MSGCFG_XTD) {
477 id = cc770_read_reg(priv, msgobj[mo].id[3]);
478 id |= cc770_read_reg(priv, msgobj[mo].id[2]) << 8;
479 id |= cc770_read_reg(priv, msgobj[mo].id[1]) << 16;
480 id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 24;
481 id >>= 3;
482 id |= CAN_EFF_FLAG;
483 } else {
484 id = cc770_read_reg(priv, msgobj[mo].id[1]);
485 id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 8;
486 id >>= 5;
487 }
488
489 cf->can_id = id;
490 cf->len = can_cc_dlc2len((config & 0xf0) >> 4);
491 for (i = 0; i < cf->len; i++)
492 cf->data[i] = cc770_read_reg(priv, msgobj[mo].data[i]);
493
494 stats->rx_bytes += cf->len;
495 }
496 stats->rx_packets++;
497
498 netif_rx(skb);
499 }
500
cc770_err(struct net_device * dev,u8 status)501 static int cc770_err(struct net_device *dev, u8 status)
502 {
503 struct cc770_priv *priv = netdev_priv(dev);
504 struct can_frame *cf;
505 struct sk_buff *skb;
506 u8 lec;
507
508 netdev_dbg(dev, "status interrupt (%#x)\n", status);
509
510 skb = alloc_can_err_skb(dev, &cf);
511 if (!skb)
512 return -ENOMEM;
513
514 /* Use extended functions of the CC770 */
515 if (priv->control_normal_mode & CTRL_EAF) {
516 cf->can_id |= CAN_ERR_CNT;
517 cf->data[6] = cc770_read_reg(priv, tx_error_counter);
518 cf->data[7] = cc770_read_reg(priv, rx_error_counter);
519 }
520
521 if (status & STAT_BOFF) {
522 /* Disable interrupts */
523 cc770_write_reg(priv, control, CTRL_INI);
524 cf->can_id |= CAN_ERR_BUSOFF;
525 priv->can.state = CAN_STATE_BUS_OFF;
526 priv->can.can_stats.bus_off++;
527 can_bus_off(dev);
528 } else if (status & STAT_WARN) {
529 cf->can_id |= CAN_ERR_CRTL;
530 /* Only the CC770 does show error passive */
531 if (cf->data[7] > 127) {
532 cf->data[1] = CAN_ERR_CRTL_RX_PASSIVE |
533 CAN_ERR_CRTL_TX_PASSIVE;
534 priv->can.state = CAN_STATE_ERROR_PASSIVE;
535 priv->can.can_stats.error_passive++;
536 } else {
537 cf->data[1] = CAN_ERR_CRTL_RX_WARNING |
538 CAN_ERR_CRTL_TX_WARNING;
539 priv->can.state = CAN_STATE_ERROR_WARNING;
540 priv->can.can_stats.error_warning++;
541 }
542 } else {
543 /* Back to error active */
544 cf->can_id |= CAN_ERR_PROT;
545 cf->data[2] = CAN_ERR_PROT_ACTIVE;
546 priv->can.state = CAN_STATE_ERROR_ACTIVE;
547 }
548
549 lec = status & STAT_LEC_MASK;
550 if (lec < 7 && lec > 0) {
551 if (lec == STAT_LEC_ACK) {
552 cf->can_id |= CAN_ERR_ACK;
553 } else {
554 cf->can_id |= CAN_ERR_PROT;
555 switch (lec) {
556 case STAT_LEC_STUFF:
557 cf->data[2] |= CAN_ERR_PROT_STUFF;
558 break;
559 case STAT_LEC_FORM:
560 cf->data[2] |= CAN_ERR_PROT_FORM;
561 break;
562 case STAT_LEC_BIT1:
563 cf->data[2] |= CAN_ERR_PROT_BIT1;
564 break;
565 case STAT_LEC_BIT0:
566 cf->data[2] |= CAN_ERR_PROT_BIT0;
567 break;
568 case STAT_LEC_CRC:
569 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
570 break;
571 }
572 }
573 }
574
575
576 netif_rx(skb);
577
578 return 0;
579 }
580
cc770_status_interrupt(struct net_device * dev)581 static int cc770_status_interrupt(struct net_device *dev)
582 {
583 struct cc770_priv *priv = netdev_priv(dev);
584 u8 status;
585
586 status = cc770_read_reg(priv, status);
587 /* Reset the status register including RXOK and TXOK */
588 cc770_write_reg(priv, status, STAT_LEC_MASK);
589
590 if (status & (STAT_WARN | STAT_BOFF) ||
591 (status & STAT_LEC_MASK) != STAT_LEC_MASK) {
592 cc770_err(dev, status);
593 return status & STAT_BOFF;
594 }
595
596 return 0;
597 }
598
cc770_rx_interrupt(struct net_device * dev,unsigned int o)599 static void cc770_rx_interrupt(struct net_device *dev, unsigned int o)
600 {
601 struct cc770_priv *priv = netdev_priv(dev);
602 struct net_device_stats *stats = &dev->stats;
603 unsigned int mo = obj2msgobj(o);
604 u8 ctrl1;
605 int n = CC770_MAX_MSG;
606
607 while (n--) {
608 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1);
609
610 if (!(ctrl1 & NEWDAT_SET)) {
611 /* Check for RTR if additional functions are enabled */
612 if (priv->control_normal_mode & CTRL_EAF) {
613 if (!(cc770_read_reg(priv, msgobj[mo].ctrl0) &
614 INTPND_SET))
615 break;
616 } else {
617 break;
618 }
619 }
620
621 if (ctrl1 & MSGLST_SET) {
622 stats->rx_over_errors++;
623 stats->rx_errors++;
624 }
625 if (mo < MSGOBJ_LAST)
626 cc770_write_reg(priv, msgobj[mo].ctrl1,
627 NEWDAT_RES | MSGLST_RES |
628 TXRQST_UNC | RMTPND_UNC);
629 cc770_rx(dev, mo, ctrl1);
630
631 cc770_write_reg(priv, msgobj[mo].ctrl0,
632 MSGVAL_SET | TXIE_RES |
633 RXIE_SET | INTPND_RES);
634 cc770_write_reg(priv, msgobj[mo].ctrl1,
635 NEWDAT_RES | MSGLST_RES |
636 TXRQST_RES | RMTPND_RES);
637 }
638 }
639
cc770_rtr_interrupt(struct net_device * dev,unsigned int o)640 static void cc770_rtr_interrupt(struct net_device *dev, unsigned int o)
641 {
642 struct cc770_priv *priv = netdev_priv(dev);
643 unsigned int mo = obj2msgobj(o);
644 u8 ctrl0, ctrl1;
645 int n = CC770_MAX_MSG;
646
647 while (n--) {
648 ctrl0 = cc770_read_reg(priv, msgobj[mo].ctrl0);
649 if (!(ctrl0 & INTPND_SET))
650 break;
651
652 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1);
653 cc770_rx(dev, mo, ctrl1);
654
655 cc770_write_reg(priv, msgobj[mo].ctrl0,
656 MSGVAL_SET | TXIE_RES |
657 RXIE_SET | INTPND_RES);
658 cc770_write_reg(priv, msgobj[mo].ctrl1,
659 NEWDAT_RES | CPUUPD_SET |
660 TXRQST_RES | RMTPND_RES);
661 }
662 }
663
cc770_tx_interrupt(struct net_device * dev,unsigned int o)664 static void cc770_tx_interrupt(struct net_device *dev, unsigned int o)
665 {
666 struct cc770_priv *priv = netdev_priv(dev);
667 struct net_device_stats *stats = &dev->stats;
668 unsigned int mo = obj2msgobj(o);
669 u8 ctrl1;
670
671 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1);
672
673 cc770_write_reg(priv, msgobj[mo].ctrl0,
674 MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES);
675 cc770_write_reg(priv, msgobj[mo].ctrl1,
676 RMTPND_RES | TXRQST_RES | MSGLST_RES | NEWDAT_RES);
677
678 if (unlikely(!priv->tx_skb)) {
679 netdev_err(dev, "missing tx skb in tx interrupt\n");
680 return;
681 }
682
683 if (unlikely(ctrl1 & MSGLST_SET)) {
684 stats->rx_over_errors++;
685 stats->rx_errors++;
686 }
687
688 /* When the CC770 is sending an RTR message and it receives a regular
689 * message that matches the id of the RTR message, it will overwrite the
690 * outgoing message in the TX register. When this happens we must
691 * process the received message and try to transmit the outgoing skb
692 * again.
693 */
694 if (unlikely(ctrl1 & NEWDAT_SET)) {
695 cc770_rx(dev, mo, ctrl1);
696 cc770_tx(dev, mo);
697 return;
698 }
699
700 can_put_echo_skb(priv->tx_skb, dev, 0, 0);
701 stats->tx_bytes += can_get_echo_skb(dev, 0, NULL);
702 stats->tx_packets++;
703 priv->tx_skb = NULL;
704
705 netif_wake_queue(dev);
706 }
707
cc770_interrupt(int irq,void * dev_id)708 static irqreturn_t cc770_interrupt(int irq, void *dev_id)
709 {
710 struct net_device *dev = (struct net_device *)dev_id;
711 struct cc770_priv *priv = netdev_priv(dev);
712 u8 intid;
713 int o, n = 0;
714
715 /* Shared interrupts and IRQ off? */
716 if (priv->can.state == CAN_STATE_STOPPED)
717 return IRQ_NONE;
718
719 if (priv->pre_irq)
720 priv->pre_irq(priv);
721
722 while (n < CC770_MAX_IRQ) {
723 /* Read the highest pending interrupt request */
724 intid = cc770_read_reg(priv, interrupt);
725 if (!intid)
726 break;
727 n++;
728
729 if (intid == 1) {
730 /* Exit in case of bus-off */
731 if (cc770_status_interrupt(dev))
732 break;
733 } else {
734 o = intid2obj(intid);
735
736 if (o >= CC770_OBJ_MAX) {
737 netdev_err(dev, "Unexpected interrupt id %d\n",
738 intid);
739 continue;
740 }
741
742 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RTR)
743 cc770_rtr_interrupt(dev, o);
744 else if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX)
745 cc770_rx_interrupt(dev, o);
746 else
747 cc770_tx_interrupt(dev, o);
748 }
749 }
750
751 if (priv->post_irq)
752 priv->post_irq(priv);
753
754 if (n >= CC770_MAX_IRQ)
755 netdev_dbg(dev, "%d messages handled in ISR", n);
756
757 return (n) ? IRQ_HANDLED : IRQ_NONE;
758 }
759
cc770_open(struct net_device * dev)760 static int cc770_open(struct net_device *dev)
761 {
762 struct cc770_priv *priv = netdev_priv(dev);
763 int err;
764
765 /* set chip into reset mode */
766 set_reset_mode(dev);
767
768 /* common open */
769 err = open_candev(dev);
770 if (err)
771 return err;
772
773 err = request_irq(dev->irq, &cc770_interrupt, priv->irq_flags,
774 dev->name, dev);
775 if (err) {
776 close_candev(dev);
777 return -EAGAIN;
778 }
779
780 /* init and start chip */
781 cc770_start(dev);
782
783 netif_start_queue(dev);
784
785 return 0;
786 }
787
cc770_close(struct net_device * dev)788 static int cc770_close(struct net_device *dev)
789 {
790 netif_stop_queue(dev);
791 set_reset_mode(dev);
792
793 free_irq(dev->irq, dev);
794 close_candev(dev);
795
796 return 0;
797 }
798
alloc_cc770dev(int sizeof_priv)799 struct net_device *alloc_cc770dev(int sizeof_priv)
800 {
801 struct net_device *dev;
802 struct cc770_priv *priv;
803
804 dev = alloc_candev(sizeof(struct cc770_priv) + sizeof_priv,
805 CC770_ECHO_SKB_MAX);
806 if (!dev)
807 return NULL;
808
809 priv = netdev_priv(dev);
810
811 priv->dev = dev;
812 priv->can.bittiming_const = &cc770_bittiming_const;
813 priv->can.do_set_bittiming = cc770_set_bittiming;
814 priv->can.do_set_mode = cc770_set_mode;
815 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
816 priv->tx_skb = NULL;
817
818 memcpy(priv->obj_flags, cc770_obj_flags, sizeof(cc770_obj_flags));
819
820 if (sizeof_priv)
821 priv->priv = (void *)priv + sizeof(struct cc770_priv);
822
823 return dev;
824 }
825 EXPORT_SYMBOL_GPL(alloc_cc770dev);
826
free_cc770dev(struct net_device * dev)827 void free_cc770dev(struct net_device *dev)
828 {
829 free_candev(dev);
830 }
831 EXPORT_SYMBOL_GPL(free_cc770dev);
832
833 static const struct net_device_ops cc770_netdev_ops = {
834 .ndo_open = cc770_open,
835 .ndo_stop = cc770_close,
836 .ndo_start_xmit = cc770_start_xmit,
837 .ndo_change_mtu = can_change_mtu,
838 };
839
840 static const struct ethtool_ops cc770_ethtool_ops = {
841 .get_ts_info = ethtool_op_get_ts_info,
842 };
843
register_cc770dev(struct net_device * dev)844 int register_cc770dev(struct net_device *dev)
845 {
846 struct cc770_priv *priv = netdev_priv(dev);
847 int err;
848
849 err = cc770_probe_chip(dev);
850 if (err)
851 return err;
852
853 dev->netdev_ops = &cc770_netdev_ops;
854 dev->ethtool_ops = &cc770_ethtool_ops;
855
856 dev->flags |= IFF_ECHO; /* we support local echo */
857
858 /* Should we use additional functions? */
859 if (!i82527_compat && priv->control_normal_mode & CTRL_EAF) {
860 priv->can.do_get_berr_counter = cc770_get_berr_counter;
861 priv->control_normal_mode = CTRL_IE | CTRL_EAF | CTRL_EIE;
862 netdev_dbg(dev, "i82527 mode with additional functions\n");
863 } else {
864 priv->control_normal_mode = CTRL_IE | CTRL_EIE;
865 netdev_dbg(dev, "strict i82527 compatibility mode\n");
866 }
867
868 chipset_init(priv);
869 set_reset_mode(dev);
870
871 return register_candev(dev);
872 }
873 EXPORT_SYMBOL_GPL(register_cc770dev);
874
unregister_cc770dev(struct net_device * dev)875 void unregister_cc770dev(struct net_device *dev)
876 {
877 set_reset_mode(dev);
878 unregister_candev(dev);
879 }
880 EXPORT_SYMBOL_GPL(unregister_cc770dev);
881
cc770_init(void)882 static __init int cc770_init(void)
883 {
884 if (msgobj15_eff) {
885 cc770_obj_flags[CC770_OBJ_RX0] |= CC770_OBJ_FLAG_EFF;
886 cc770_obj_flags[CC770_OBJ_RX1] &= ~CC770_OBJ_FLAG_EFF;
887 }
888
889 pr_info("CAN netdevice driver\n");
890
891 return 0;
892 }
893 module_init(cc770_init);
894
cc770_exit(void)895 static __exit void cc770_exit(void)
896 {
897 pr_info("driver removed\n");
898 }
899 module_exit(cc770_exit);
900