1// SPDX-License-Identifier: GPL-2.0
2//
3// mcp251xfd - Microchip MCP251xFD Family CAN controller driver
4//
5// Copyright (c) 2019, 2020, 2021 Pengutronix,
6// Marc Kleine-Budde <kernel@pengutronix.de>
7//
8
9#include "mcp251xfd.h"
10
11#include <asm/unaligned.h>
12
13static const struct regmap_config mcp251xfd_regmap_crc;
14
15static int
16mcp251xfd_regmap_nocrc_write(void *context, const void *data, size_t count)
17{
18 struct spi_device *spi = context;
19
20 return spi_write(spi, buf: data, len: count);
21}
22
23static int
24mcp251xfd_regmap_nocrc_gather_write(void *context,
25 const void *reg, size_t reg_len,
26 const void *val, size_t val_len)
27{
28 struct spi_device *spi = context;
29 struct mcp251xfd_priv *priv = spi_get_drvdata(spi);
30 struct mcp251xfd_map_buf_nocrc *buf_tx = priv->map_buf_nocrc_tx;
31 struct spi_transfer xfer[] = {
32 {
33 .tx_buf = buf_tx,
34 .len = sizeof(buf_tx->cmd) + val_len,
35 },
36 };
37
38 BUILD_BUG_ON(sizeof(buf_tx->cmd) != sizeof(__be16));
39
40 if (IS_ENABLED(CONFIG_CAN_MCP251XFD_SANITY) &&
41 reg_len != sizeof(buf_tx->cmd.cmd))
42 return -EINVAL;
43
44 memcpy(&buf_tx->cmd, reg, sizeof(buf_tx->cmd));
45 memcpy(buf_tx->data, val, val_len);
46
47 return spi_sync_transfer(spi, xfers: xfer, ARRAY_SIZE(xfer));
48}
49
50static inline bool
51mcp251xfd_update_bits_read_reg(const struct mcp251xfd_priv *priv,
52 unsigned int reg)
53{
54 struct mcp251xfd_rx_ring *ring;
55 int n;
56
57 switch (reg) {
58 case MCP251XFD_REG_INT:
59 case MCP251XFD_REG_TEFCON:
60 case MCP251XFD_REG_FLTCON(0):
61 case MCP251XFD_REG_ECCSTAT:
62 case MCP251XFD_REG_CRC:
63 return false;
64 case MCP251XFD_REG_CON:
65 case MCP251XFD_REG_OSC:
66 case MCP251XFD_REG_ECCCON:
67 return true;
68 default:
69 mcp251xfd_for_each_rx_ring(priv, ring, n) {
70 if (reg == MCP251XFD_REG_FIFOCON(ring->fifo_nr))
71 return false;
72 if (reg == MCP251XFD_REG_FIFOSTA(ring->fifo_nr))
73 return true;
74 }
75
76 WARN(1, "Status of reg 0x%04x unknown.\n", reg);
77 }
78
79 return true;
80}
81
82static int
83mcp251xfd_regmap_nocrc_update_bits(void *context, unsigned int reg,
84 unsigned int mask, unsigned int val)
85{
86 struct spi_device *spi = context;
87 struct mcp251xfd_priv *priv = spi_get_drvdata(spi);
88 struct mcp251xfd_map_buf_nocrc *buf_rx = priv->map_buf_nocrc_rx;
89 struct mcp251xfd_map_buf_nocrc *buf_tx = priv->map_buf_nocrc_tx;
90 __le32 orig_le32 = 0, mask_le32, val_le32, tmp_le32;
91 u8 first_byte, last_byte, len;
92 int err;
93
94 BUILD_BUG_ON(sizeof(buf_rx->cmd) != sizeof(__be16));
95 BUILD_BUG_ON(sizeof(buf_tx->cmd) != sizeof(__be16));
96
97 if (IS_ENABLED(CONFIG_CAN_MCP251XFD_SANITY) &&
98 mask == 0)
99 return -EINVAL;
100
101 first_byte = mcp251xfd_first_byte_set(mask);
102 last_byte = mcp251xfd_last_byte_set(mask);
103 len = last_byte - first_byte + 1;
104
105 if (mcp251xfd_update_bits_read_reg(priv, reg)) {
106 struct spi_transfer xfer[2] = { };
107 struct spi_message msg;
108
109 spi_message_init(m: &msg);
110 spi_message_add_tail(t: &xfer[0], m: &msg);
111
112 if (priv->devtype_data.quirks & MCP251XFD_QUIRK_HALF_DUPLEX) {
113 xfer[0].tx_buf = buf_tx;
114 xfer[0].len = sizeof(buf_tx->cmd);
115
116 xfer[1].rx_buf = buf_rx->data;
117 xfer[1].len = len;
118 spi_message_add_tail(t: &xfer[1], m: &msg);
119 } else {
120 xfer[0].tx_buf = buf_tx;
121 xfer[0].rx_buf = buf_rx;
122 xfer[0].len = sizeof(buf_tx->cmd) + len;
123
124 if (MCP251XFD_SANITIZE_SPI)
125 memset(buf_tx->data, 0x0, len);
126 }
127
128 mcp251xfd_spi_cmd_read_nocrc(cmd: &buf_tx->cmd, addr: reg + first_byte);
129 err = spi_sync(spi, message: &msg);
130 if (err)
131 return err;
132
133 memcpy(&orig_le32, buf_rx->data, len);
134 }
135
136 mask_le32 = cpu_to_le32(mask >> BITS_PER_BYTE * first_byte);
137 val_le32 = cpu_to_le32(val >> BITS_PER_BYTE * first_byte);
138
139 tmp_le32 = orig_le32 & ~mask_le32;
140 tmp_le32 |= val_le32 & mask_le32;
141
142 mcp251xfd_spi_cmd_write_nocrc(cmd: &buf_tx->cmd, addr: reg + first_byte);
143 memcpy(buf_tx->data, &tmp_le32, len);
144
145 return spi_write(spi, buf: buf_tx, len: sizeof(buf_tx->cmd) + len);
146}
147
148static int
149mcp251xfd_regmap_nocrc_read(void *context,
150 const void *reg, size_t reg_len,
151 void *val_buf, size_t val_len)
152{
153 struct spi_device *spi = context;
154 struct mcp251xfd_priv *priv = spi_get_drvdata(spi);
155 struct mcp251xfd_map_buf_nocrc *buf_rx = priv->map_buf_nocrc_rx;
156 struct mcp251xfd_map_buf_nocrc *buf_tx = priv->map_buf_nocrc_tx;
157 struct spi_transfer xfer[2] = { };
158 struct spi_message msg;
159 int err;
160
161 BUILD_BUG_ON(sizeof(buf_rx->cmd) != sizeof(__be16));
162 BUILD_BUG_ON(sizeof(buf_tx->cmd) != sizeof(__be16));
163
164 if (IS_ENABLED(CONFIG_CAN_MCP251XFD_SANITY) &&
165 reg_len != sizeof(buf_tx->cmd.cmd))
166 return -EINVAL;
167
168 spi_message_init(m: &msg);
169 spi_message_add_tail(t: &xfer[0], m: &msg);
170
171 if (priv->devtype_data.quirks & MCP251XFD_QUIRK_HALF_DUPLEX) {
172 xfer[0].tx_buf = reg;
173 xfer[0].len = sizeof(buf_tx->cmd);
174
175 xfer[1].rx_buf = val_buf;
176 xfer[1].len = val_len;
177 spi_message_add_tail(t: &xfer[1], m: &msg);
178 } else {
179 xfer[0].tx_buf = buf_tx;
180 xfer[0].rx_buf = buf_rx;
181 xfer[0].len = sizeof(buf_tx->cmd) + val_len;
182
183 memcpy(&buf_tx->cmd, reg, sizeof(buf_tx->cmd));
184 if (MCP251XFD_SANITIZE_SPI)
185 memset(buf_tx->data, 0x0, val_len);
186 }
187
188 err = spi_sync(spi, message: &msg);
189 if (err)
190 return err;
191
192 if (!(priv->devtype_data.quirks & MCP251XFD_QUIRK_HALF_DUPLEX))
193 memcpy(val_buf, buf_rx->data, val_len);
194
195 return 0;
196}
197
198static int
199mcp251xfd_regmap_crc_gather_write(void *context,
200 const void *reg_p, size_t reg_len,
201 const void *val, size_t val_len)
202{
203 struct spi_device *spi = context;
204 struct mcp251xfd_priv *priv = spi_get_drvdata(spi);
205 struct mcp251xfd_map_buf_crc *buf_tx = priv->map_buf_crc_tx;
206 struct spi_transfer xfer[] = {
207 {
208 .tx_buf = buf_tx,
209 .len = sizeof(buf_tx->cmd) + val_len +
210 sizeof(buf_tx->crc),
211 },
212 };
213 u16 reg = *(u16 *)reg_p;
214 u16 crc;
215
216 BUILD_BUG_ON(sizeof(buf_tx->cmd) != sizeof(__be16) + sizeof(u8));
217
218 if (IS_ENABLED(CONFIG_CAN_MCP251XFD_SANITY) &&
219 reg_len != sizeof(buf_tx->cmd.cmd) +
220 mcp251xfd_regmap_crc.pad_bits / BITS_PER_BYTE)
221 return -EINVAL;
222
223 mcp251xfd_spi_cmd_write_crc(cmd: &buf_tx->cmd, addr: reg, len: val_len);
224 memcpy(buf_tx->data, val, val_len);
225
226 crc = mcp251xfd_crc16_compute(data: buf_tx, data_size: sizeof(buf_tx->cmd) + val_len);
227 put_unaligned_be16(val: crc, p: buf_tx->data + val_len);
228
229 return spi_sync_transfer(spi, xfers: xfer, ARRAY_SIZE(xfer));
230}
231
232static int
233mcp251xfd_regmap_crc_write(void *context,
234 const void *data, size_t count)
235{
236 const size_t data_offset = sizeof(__be16) +
237 mcp251xfd_regmap_crc.pad_bits / BITS_PER_BYTE;
238
239 return mcp251xfd_regmap_crc_gather_write(context,
240 reg_p: data, reg_len: data_offset,
241 val: data + data_offset,
242 val_len: count - data_offset);
243}
244
245static int
246mcp251xfd_regmap_crc_read_check_crc(const struct mcp251xfd_map_buf_crc * const buf_rx,
247 const struct mcp251xfd_map_buf_crc * const buf_tx,
248 unsigned int data_len)
249{
250 u16 crc_received, crc_calculated;
251
252 crc_received = get_unaligned_be16(p: buf_rx->data + data_len);
253 crc_calculated = mcp251xfd_crc16_compute2(cmd: &buf_tx->cmd,
254 cmd_size: sizeof(buf_tx->cmd),
255 data: buf_rx->data,
256 data_size: data_len);
257 if (crc_received != crc_calculated)
258 return -EBADMSG;
259
260 return 0;
261}
262
263static int
264mcp251xfd_regmap_crc_read_one(struct mcp251xfd_priv *priv,
265 struct spi_message *msg, unsigned int data_len)
266{
267 const struct mcp251xfd_map_buf_crc *buf_rx = priv->map_buf_crc_rx;
268 const struct mcp251xfd_map_buf_crc *buf_tx = priv->map_buf_crc_tx;
269 int err;
270
271 BUILD_BUG_ON(sizeof(buf_rx->cmd) != sizeof(__be16) + sizeof(u8));
272 BUILD_BUG_ON(sizeof(buf_tx->cmd) != sizeof(__be16) + sizeof(u8));
273
274 err = spi_sync(spi: priv->spi, message: msg);
275 if (err)
276 return err;
277
278 return mcp251xfd_regmap_crc_read_check_crc(buf_rx, buf_tx, data_len);
279}
280
281static int
282mcp251xfd_regmap_crc_read(void *context,
283 const void *reg_p, size_t reg_len,
284 void *val_buf, size_t val_len)
285{
286 struct spi_device *spi = context;
287 struct mcp251xfd_priv *priv = spi_get_drvdata(spi);
288 struct mcp251xfd_map_buf_crc *buf_rx = priv->map_buf_crc_rx;
289 struct mcp251xfd_map_buf_crc *buf_tx = priv->map_buf_crc_tx;
290 struct spi_transfer xfer[2] = { };
291 struct spi_message msg;
292 u16 reg = *(u16 *)reg_p;
293 int i, err;
294
295 BUILD_BUG_ON(sizeof(buf_rx->cmd) != sizeof(__be16) + sizeof(u8));
296 BUILD_BUG_ON(sizeof(buf_tx->cmd) != sizeof(__be16) + sizeof(u8));
297
298 if (IS_ENABLED(CONFIG_CAN_MCP251XFD_SANITY) &&
299 reg_len != sizeof(buf_tx->cmd.cmd) +
300 mcp251xfd_regmap_crc.pad_bits / BITS_PER_BYTE)
301 return -EINVAL;
302
303 spi_message_init(m: &msg);
304 spi_message_add_tail(t: &xfer[0], m: &msg);
305
306 if (priv->devtype_data.quirks & MCP251XFD_QUIRK_HALF_DUPLEX) {
307 xfer[0].tx_buf = buf_tx;
308 xfer[0].len = sizeof(buf_tx->cmd);
309
310 xfer[1].rx_buf = buf_rx->data;
311 xfer[1].len = val_len + sizeof(buf_tx->crc);
312 spi_message_add_tail(t: &xfer[1], m: &msg);
313 } else {
314 xfer[0].tx_buf = buf_tx;
315 xfer[0].rx_buf = buf_rx;
316 xfer[0].len = sizeof(buf_tx->cmd) + val_len +
317 sizeof(buf_tx->crc);
318
319 if (MCP251XFD_SANITIZE_SPI)
320 memset(buf_tx->data, 0x0, val_len +
321 sizeof(buf_tx->crc));
322 }
323
324 mcp251xfd_spi_cmd_read_crc(cmd: &buf_tx->cmd, addr: reg, len: val_len);
325
326 for (i = 0; i < MCP251XFD_READ_CRC_RETRIES_MAX; i++) {
327 err = mcp251xfd_regmap_crc_read_one(priv, msg: &msg, data_len: val_len);
328 if (!err)
329 goto out;
330 if (err != -EBADMSG)
331 return err;
332
333 /* MCP251XFD_REG_TBC is the time base counter
334 * register. It increments once per SYS clock tick,
335 * which is 20 or 40 MHz.
336 *
337 * Observation on the mcp2518fd shows that if the
338 * lowest byte (which is transferred first on the SPI
339 * bus) of that register is 0x00 or 0x80 the
340 * calculated CRC doesn't always match the transferred
341 * one. On the mcp2517fd this problem is not limited
342 * to the first byte being 0x00 or 0x80.
343 *
344 * If the highest bit in the lowest byte is flipped
345 * the transferred CRC matches the calculated one. We
346 * assume for now the CRC operates on the correct
347 * data.
348 */
349 if (reg == MCP251XFD_REG_TBC &&
350 ((buf_rx->data[0] & 0xf8) == 0x0 ||
351 (buf_rx->data[0] & 0xf8) == 0x80)) {
352 /* Flip highest bit in lowest byte of le32 */
353 buf_rx->data[0] ^= 0x80;
354
355 /* re-check CRC */
356 err = mcp251xfd_regmap_crc_read_check_crc(buf_rx,
357 buf_tx,
358 data_len: val_len);
359 if (!err) {
360 /* If CRC is now correct, assume
361 * flipped data is OK.
362 */
363 goto out;
364 }
365 }
366
367 /* MCP251XFD_REG_OSC is the first ever reg we read from.
368 *
369 * The chip may be in deep sleep and this SPI transfer
370 * (i.e. the assertion of the CS) will wake the chip
371 * up. This takes about 3ms. The CRC of this transfer
372 * is wrong.
373 *
374 * Or there isn't a chip at all, in this case the CRC
375 * will be wrong, too.
376 *
377 * In both cases ignore the CRC and copy the read data
378 * to the caller. It will take care of both cases.
379 *
380 */
381 if (reg == MCP251XFD_REG_OSC && val_len == sizeof(__le32)) {
382 err = 0;
383 goto out;
384 }
385
386 netdev_info(dev: priv->ndev,
387 format: "CRC read error at address 0x%04x (length=%zd, data=%*ph, CRC=0x%04x) retrying.\n",
388 reg, val_len, (int)val_len, buf_rx->data,
389 get_unaligned_be16(p: buf_rx->data + val_len));
390 }
391
392 if (err) {
393 netdev_err(dev: priv->ndev,
394 format: "CRC read error at address 0x%04x (length=%zd, data=%*ph, CRC=0x%04x).\n",
395 reg, val_len, (int)val_len, buf_rx->data,
396 get_unaligned_be16(p: buf_rx->data + val_len));
397
398 return err;
399 }
400 out:
401 memcpy(val_buf, buf_rx->data, val_len);
402
403 return 0;
404}
405
406static const struct regmap_range mcp251xfd_reg_table_yes_range[] = {
407 regmap_reg_range(0x000, 0x2ec), /* CAN FD Controller Module SFR */
408 regmap_reg_range(0x400, 0xbfc), /* RAM */
409 regmap_reg_range(0xe00, 0xe14), /* MCP2517/18FD SFR */
410};
411
412static const struct regmap_access_table mcp251xfd_reg_table = {
413 .yes_ranges = mcp251xfd_reg_table_yes_range,
414 .n_yes_ranges = ARRAY_SIZE(mcp251xfd_reg_table_yes_range),
415};
416
417static const struct regmap_config mcp251xfd_regmap_nocrc = {
418 .name = "nocrc",
419 .reg_bits = 16,
420 .reg_stride = 4,
421 .pad_bits = 0,
422 .val_bits = 32,
423 .max_register = 0xffc,
424 .wr_table = &mcp251xfd_reg_table,
425 .rd_table = &mcp251xfd_reg_table,
426 .cache_type = REGCACHE_NONE,
427 .read_flag_mask = (__force unsigned long)
428 cpu_to_be16(MCP251XFD_SPI_INSTRUCTION_READ),
429 .write_flag_mask = (__force unsigned long)
430 cpu_to_be16(MCP251XFD_SPI_INSTRUCTION_WRITE),
431};
432
433static const struct regmap_bus mcp251xfd_bus_nocrc = {
434 .write = mcp251xfd_regmap_nocrc_write,
435 .gather_write = mcp251xfd_regmap_nocrc_gather_write,
436 .reg_update_bits = mcp251xfd_regmap_nocrc_update_bits,
437 .read = mcp251xfd_regmap_nocrc_read,
438 .reg_format_endian_default = REGMAP_ENDIAN_BIG,
439 .val_format_endian_default = REGMAP_ENDIAN_LITTLE,
440 .max_raw_read = sizeof_field(struct mcp251xfd_map_buf_nocrc, data),
441 .max_raw_write = sizeof_field(struct mcp251xfd_map_buf_nocrc, data),
442};
443
444static const struct regmap_config mcp251xfd_regmap_crc = {
445 .name = "crc",
446 .reg_bits = 16,
447 .reg_stride = 4,
448 .pad_bits = 16, /* keep data bits aligned */
449 .val_bits = 32,
450 .max_register = 0xffc,
451 .wr_table = &mcp251xfd_reg_table,
452 .rd_table = &mcp251xfd_reg_table,
453 .cache_type = REGCACHE_NONE,
454};
455
456static const struct regmap_bus mcp251xfd_bus_crc = {
457 .write = mcp251xfd_regmap_crc_write,
458 .gather_write = mcp251xfd_regmap_crc_gather_write,
459 .read = mcp251xfd_regmap_crc_read,
460 .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
461 .val_format_endian_default = REGMAP_ENDIAN_LITTLE,
462 .max_raw_read = sizeof_field(struct mcp251xfd_map_buf_crc, data),
463 .max_raw_write = sizeof_field(struct mcp251xfd_map_buf_crc, data),
464};
465
466static inline bool
467mcp251xfd_regmap_use_nocrc(struct mcp251xfd_priv *priv)
468{
469 return (!(priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_REG)) ||
470 (!(priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_RX));
471}
472
473static inline bool
474mcp251xfd_regmap_use_crc(struct mcp251xfd_priv *priv)
475{
476 return (priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_REG) ||
477 (priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_RX);
478}
479
480static int
481mcp251xfd_regmap_init_nocrc(struct mcp251xfd_priv *priv)
482{
483 if (!priv->map_nocrc) {
484 struct regmap *map;
485
486 map = devm_regmap_init(&priv->spi->dev, &mcp251xfd_bus_nocrc,
487 priv->spi, &mcp251xfd_regmap_nocrc);
488 if (IS_ERR(ptr: map))
489 return PTR_ERR(ptr: map);
490
491 priv->map_nocrc = map;
492 }
493
494 if (!priv->map_buf_nocrc_rx) {
495 priv->map_buf_nocrc_rx =
496 devm_kzalloc(dev: &priv->spi->dev,
497 size: sizeof(*priv->map_buf_nocrc_rx),
498 GFP_KERNEL);
499 if (!priv->map_buf_nocrc_rx)
500 return -ENOMEM;
501 }
502
503 if (!priv->map_buf_nocrc_tx) {
504 priv->map_buf_nocrc_tx =
505 devm_kzalloc(dev: &priv->spi->dev,
506 size: sizeof(*priv->map_buf_nocrc_tx),
507 GFP_KERNEL);
508 if (!priv->map_buf_nocrc_tx)
509 return -ENOMEM;
510 }
511
512 if (!(priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_REG))
513 priv->map_reg = priv->map_nocrc;
514
515 if (!(priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_RX))
516 priv->map_rx = priv->map_nocrc;
517
518 return 0;
519}
520
521static void mcp251xfd_regmap_destroy_nocrc(struct mcp251xfd_priv *priv)
522{
523 if (priv->map_buf_nocrc_rx) {
524 devm_kfree(dev: &priv->spi->dev, p: priv->map_buf_nocrc_rx);
525 priv->map_buf_nocrc_rx = NULL;
526 }
527 if (priv->map_buf_nocrc_tx) {
528 devm_kfree(dev: &priv->spi->dev, p: priv->map_buf_nocrc_tx);
529 priv->map_buf_nocrc_tx = NULL;
530 }
531}
532
533static int
534mcp251xfd_regmap_init_crc(struct mcp251xfd_priv *priv)
535{
536 if (!priv->map_crc) {
537 struct regmap *map;
538
539 map = devm_regmap_init(&priv->spi->dev, &mcp251xfd_bus_crc,
540 priv->spi, &mcp251xfd_regmap_crc);
541 if (IS_ERR(ptr: map))
542 return PTR_ERR(ptr: map);
543
544 priv->map_crc = map;
545 }
546
547 if (!priv->map_buf_crc_rx) {
548 priv->map_buf_crc_rx =
549 devm_kzalloc(dev: &priv->spi->dev,
550 size: sizeof(*priv->map_buf_crc_rx),
551 GFP_KERNEL);
552 if (!priv->map_buf_crc_rx)
553 return -ENOMEM;
554 }
555
556 if (!priv->map_buf_crc_tx) {
557 priv->map_buf_crc_tx =
558 devm_kzalloc(dev: &priv->spi->dev,
559 size: sizeof(*priv->map_buf_crc_tx),
560 GFP_KERNEL);
561 if (!priv->map_buf_crc_tx)
562 return -ENOMEM;
563 }
564
565 if (priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_REG)
566 priv->map_reg = priv->map_crc;
567
568 if (priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_RX)
569 priv->map_rx = priv->map_crc;
570
571 return 0;
572}
573
574static void mcp251xfd_regmap_destroy_crc(struct mcp251xfd_priv *priv)
575{
576 if (priv->map_buf_crc_rx) {
577 devm_kfree(dev: &priv->spi->dev, p: priv->map_buf_crc_rx);
578 priv->map_buf_crc_rx = NULL;
579 }
580 if (priv->map_buf_crc_tx) {
581 devm_kfree(dev: &priv->spi->dev, p: priv->map_buf_crc_tx);
582 priv->map_buf_crc_tx = NULL;
583 }
584}
585
586int mcp251xfd_regmap_init(struct mcp251xfd_priv *priv)
587{
588 int err;
589
590 if (mcp251xfd_regmap_use_nocrc(priv)) {
591 err = mcp251xfd_regmap_init_nocrc(priv);
592
593 if (err)
594 return err;
595 } else {
596 mcp251xfd_regmap_destroy_nocrc(priv);
597 }
598
599 if (mcp251xfd_regmap_use_crc(priv)) {
600 err = mcp251xfd_regmap_init_crc(priv);
601
602 if (err)
603 return err;
604 } else {
605 mcp251xfd_regmap_destroy_crc(priv);
606 }
607
608 return 0;
609}
610

source code of linux/drivers/net/can/spi/mcp251xfd/mcp251xfd-regmap.c