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[mirror_ubuntu-bionic-kernel.git] / drivers / net / can / m_can / m_can.c
1 /*
2 * CAN bus driver for Bosch M_CAN controller
3 *
4 * Copyright (C) 2014 Freescale Semiconductor, Inc.
5 * Dong Aisheng <b29396@freescale.com>
6 *
7 * Bosch M_CAN user manual can be obtained from:
8 * http://www.bosch-semiconductors.de/media/pdf_1/ipmodules_1/m_can/
9 * mcan_users_manual_v302.pdf
10 *
11 * This file is licensed under the terms of the GNU General Public
12 * License version 2. This program is licensed "as is" without any
13 * warranty of any kind, whether express or implied.
14 */
15
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/netdevice.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/platform_device.h>
26
27 #include <linux/can/dev.h>
28
29 /* napi related */
30 #define M_CAN_NAPI_WEIGHT 64
31
32 /* message ram configuration data length */
33 #define MRAM_CFG_LEN 8
34
35 /* registers definition */
36 enum m_can_reg {
37 M_CAN_CREL = 0x0,
38 M_CAN_ENDN = 0x4,
39 M_CAN_CUST = 0x8,
40 M_CAN_FBTP = 0xc,
41 M_CAN_TEST = 0x10,
42 M_CAN_RWD = 0x14,
43 M_CAN_CCCR = 0x18,
44 M_CAN_BTP = 0x1c,
45 M_CAN_TSCC = 0x20,
46 M_CAN_TSCV = 0x24,
47 M_CAN_TOCC = 0x28,
48 M_CAN_TOCV = 0x2c,
49 M_CAN_ECR = 0x40,
50 M_CAN_PSR = 0x44,
51 M_CAN_IR = 0x50,
52 M_CAN_IE = 0x54,
53 M_CAN_ILS = 0x58,
54 M_CAN_ILE = 0x5c,
55 M_CAN_GFC = 0x80,
56 M_CAN_SIDFC = 0x84,
57 M_CAN_XIDFC = 0x88,
58 M_CAN_XIDAM = 0x90,
59 M_CAN_HPMS = 0x94,
60 M_CAN_NDAT1 = 0x98,
61 M_CAN_NDAT2 = 0x9c,
62 M_CAN_RXF0C = 0xa0,
63 M_CAN_RXF0S = 0xa4,
64 M_CAN_RXF0A = 0xa8,
65 M_CAN_RXBC = 0xac,
66 M_CAN_RXF1C = 0xb0,
67 M_CAN_RXF1S = 0xb4,
68 M_CAN_RXF1A = 0xb8,
69 M_CAN_RXESC = 0xbc,
70 M_CAN_TXBC = 0xc0,
71 M_CAN_TXFQS = 0xc4,
72 M_CAN_TXESC = 0xc8,
73 M_CAN_TXBRP = 0xcc,
74 M_CAN_TXBAR = 0xd0,
75 M_CAN_TXBCR = 0xd4,
76 M_CAN_TXBTO = 0xd8,
77 M_CAN_TXBCF = 0xdc,
78 M_CAN_TXBTIE = 0xe0,
79 M_CAN_TXBCIE = 0xe4,
80 M_CAN_TXEFC = 0xf0,
81 M_CAN_TXEFS = 0xf4,
82 M_CAN_TXEFA = 0xf8,
83 };
84
85 /* m_can lec values */
86 enum m_can_lec_type {
87 LEC_NO_ERROR = 0,
88 LEC_STUFF_ERROR,
89 LEC_FORM_ERROR,
90 LEC_ACK_ERROR,
91 LEC_BIT1_ERROR,
92 LEC_BIT0_ERROR,
93 LEC_CRC_ERROR,
94 LEC_UNUSED,
95 };
96
97 enum m_can_mram_cfg {
98 MRAM_SIDF = 0,
99 MRAM_XIDF,
100 MRAM_RXF0,
101 MRAM_RXF1,
102 MRAM_RXB,
103 MRAM_TXE,
104 MRAM_TXB,
105 MRAM_CFG_NUM,
106 };
107
108 /* Fast Bit Timing & Prescaler Register (FBTP) */
109 #define FBTR_FBRP_MASK 0x1f
110 #define FBTR_FBRP_SHIFT 16
111 #define FBTR_FTSEG1_SHIFT 8
112 #define FBTR_FTSEG1_MASK (0xf << FBTR_FTSEG1_SHIFT)
113 #define FBTR_FTSEG2_SHIFT 4
114 #define FBTR_FTSEG2_MASK (0x7 << FBTR_FTSEG2_SHIFT)
115 #define FBTR_FSJW_SHIFT 0
116 #define FBTR_FSJW_MASK 0x3
117
118 /* Test Register (TEST) */
119 #define TEST_LBCK BIT(4)
120
121 /* CC Control Register(CCCR) */
122 #define CCCR_TEST BIT(7)
123 #define CCCR_CMR_MASK 0x3
124 #define CCCR_CMR_SHIFT 10
125 #define CCCR_CMR_CANFD 0x1
126 #define CCCR_CMR_CANFD_BRS 0x2
127 #define CCCR_CMR_CAN 0x3
128 #define CCCR_CME_MASK 0x3
129 #define CCCR_CME_SHIFT 8
130 #define CCCR_CME_CAN 0
131 #define CCCR_CME_CANFD 0x1
132 #define CCCR_CME_CANFD_BRS 0x2
133 #define CCCR_TEST BIT(7)
134 #define CCCR_MON BIT(5)
135 #define CCCR_CCE BIT(1)
136 #define CCCR_INIT BIT(0)
137 #define CCCR_CANFD 0x10
138
139 /* Bit Timing & Prescaler Register (BTP) */
140 #define BTR_BRP_MASK 0x3ff
141 #define BTR_BRP_SHIFT 16
142 #define BTR_TSEG1_SHIFT 8
143 #define BTR_TSEG1_MASK (0x3f << BTR_TSEG1_SHIFT)
144 #define BTR_TSEG2_SHIFT 4
145 #define BTR_TSEG2_MASK (0xf << BTR_TSEG2_SHIFT)
146 #define BTR_SJW_SHIFT 0
147 #define BTR_SJW_MASK 0xf
148
149 /* Error Counter Register(ECR) */
150 #define ECR_RP BIT(15)
151 #define ECR_REC_SHIFT 8
152 #define ECR_REC_MASK (0x7f << ECR_REC_SHIFT)
153 #define ECR_TEC_SHIFT 0
154 #define ECR_TEC_MASK 0xff
155
156 /* Protocol Status Register(PSR) */
157 #define PSR_BO BIT(7)
158 #define PSR_EW BIT(6)
159 #define PSR_EP BIT(5)
160 #define PSR_LEC_MASK 0x7
161
162 /* Interrupt Register(IR) */
163 #define IR_ALL_INT 0xffffffff
164 #define IR_STE BIT(31)
165 #define IR_FOE BIT(30)
166 #define IR_ACKE BIT(29)
167 #define IR_BE BIT(28)
168 #define IR_CRCE BIT(27)
169 #define IR_WDI BIT(26)
170 #define IR_BO BIT(25)
171 #define IR_EW BIT(24)
172 #define IR_EP BIT(23)
173 #define IR_ELO BIT(22)
174 #define IR_BEU BIT(21)
175 #define IR_BEC BIT(20)
176 #define IR_DRX BIT(19)
177 #define IR_TOO BIT(18)
178 #define IR_MRAF BIT(17)
179 #define IR_TSW BIT(16)
180 #define IR_TEFL BIT(15)
181 #define IR_TEFF BIT(14)
182 #define IR_TEFW BIT(13)
183 #define IR_TEFN BIT(12)
184 #define IR_TFE BIT(11)
185 #define IR_TCF BIT(10)
186 #define IR_TC BIT(9)
187 #define IR_HPM BIT(8)
188 #define IR_RF1L BIT(7)
189 #define IR_RF1F BIT(6)
190 #define IR_RF1W BIT(5)
191 #define IR_RF1N BIT(4)
192 #define IR_RF0L BIT(3)
193 #define IR_RF0F BIT(2)
194 #define IR_RF0W BIT(1)
195 #define IR_RF0N BIT(0)
196 #define IR_ERR_STATE (IR_BO | IR_EW | IR_EP)
197 #define IR_ERR_LEC (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE)
198 #define IR_ERR_BUS (IR_ERR_LEC | IR_WDI | IR_ELO | IR_BEU | \
199 IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | \
200 IR_RF1L | IR_RF0L)
201 #define IR_ERR_ALL (IR_ERR_STATE | IR_ERR_BUS)
202
203 /* Interrupt Line Select (ILS) */
204 #define ILS_ALL_INT0 0x0
205 #define ILS_ALL_INT1 0xFFFFFFFF
206
207 /* Interrupt Line Enable (ILE) */
208 #define ILE_EINT0 BIT(0)
209 #define ILE_EINT1 BIT(1)
210
211 /* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
212 #define RXFC_FWM_OFF 24
213 #define RXFC_FWM_MASK 0x7f
214 #define RXFC_FWM_1 (1 << RXFC_FWM_OFF)
215 #define RXFC_FS_OFF 16
216 #define RXFC_FS_MASK 0x7f
217
218 /* Rx FIFO 0/1 Status (RXF0S/RXF1S) */
219 #define RXFS_RFL BIT(25)
220 #define RXFS_FF BIT(24)
221 #define RXFS_FPI_OFF 16
222 #define RXFS_FPI_MASK 0x3f0000
223 #define RXFS_FGI_OFF 8
224 #define RXFS_FGI_MASK 0x3f00
225 #define RXFS_FFL_MASK 0x7f
226
227 /* Rx Buffer / FIFO Element Size Configuration (RXESC) */
228 #define M_CAN_RXESC_8BYTES 0x0
229 #define M_CAN_RXESC_64BYTES 0x777
230
231 /* Tx Buffer Configuration(TXBC) */
232 #define TXBC_NDTB_OFF 16
233 #define TXBC_NDTB_MASK 0x3f
234
235 /* Tx Buffer Element Size Configuration(TXESC) */
236 #define TXESC_TBDS_8BYTES 0x0
237 #define TXESC_TBDS_64BYTES 0x7
238
239 /* Tx Event FIFO Con.guration (TXEFC) */
240 #define TXEFC_EFS_OFF 16
241 #define TXEFC_EFS_MASK 0x3f
242
243 /* Message RAM Configuration (in bytes) */
244 #define SIDF_ELEMENT_SIZE 4
245 #define XIDF_ELEMENT_SIZE 8
246 #define RXF0_ELEMENT_SIZE 72
247 #define RXF1_ELEMENT_SIZE 72
248 #define RXB_ELEMENT_SIZE 16
249 #define TXE_ELEMENT_SIZE 8
250 #define TXB_ELEMENT_SIZE 72
251
252 /* Message RAM Elements */
253 #define M_CAN_FIFO_ID 0x0
254 #define M_CAN_FIFO_DLC 0x4
255 #define M_CAN_FIFO_DATA(n) (0x8 + ((n) << 2))
256
257 /* Rx Buffer Element */
258 /* R0 */
259 #define RX_BUF_ESI BIT(31)
260 #define RX_BUF_XTD BIT(30)
261 #define RX_BUF_RTR BIT(29)
262 /* R1 */
263 #define RX_BUF_ANMF BIT(31)
264 #define RX_BUF_EDL BIT(21)
265 #define RX_BUF_BRS BIT(20)
266
267 /* Tx Buffer Element */
268 /* R0 */
269 #define TX_BUF_XTD BIT(30)
270 #define TX_BUF_RTR BIT(29)
271
272 /* address offset and element number for each FIFO/Buffer in the Message RAM */
273 struct mram_cfg {
274 u16 off;
275 u8 num;
276 };
277
278 /* m_can private data structure */
279 struct m_can_priv {
280 struct can_priv can; /* must be the first member */
281 struct napi_struct napi;
282 struct net_device *dev;
283 struct device *device;
284 struct clk *hclk;
285 struct clk *cclk;
286 void __iomem *base;
287 u32 irqstatus;
288
289 /* message ram configuration */
290 void __iomem *mram_base;
291 struct mram_cfg mcfg[MRAM_CFG_NUM];
292 };
293
294 static inline u32 m_can_read(const struct m_can_priv *priv, enum m_can_reg reg)
295 {
296 return readl(priv->base + reg);
297 }
298
299 static inline void m_can_write(const struct m_can_priv *priv,
300 enum m_can_reg reg, u32 val)
301 {
302 writel(val, priv->base + reg);
303 }
304
305 static inline u32 m_can_fifo_read(const struct m_can_priv *priv,
306 u32 fgi, unsigned int offset)
307 {
308 return readl(priv->mram_base + priv->mcfg[MRAM_RXF0].off +
309 fgi * RXF0_ELEMENT_SIZE + offset);
310 }
311
312 static inline void m_can_fifo_write(const struct m_can_priv *priv,
313 u32 fpi, unsigned int offset, u32 val)
314 {
315 return writel(val, priv->mram_base + priv->mcfg[MRAM_TXB].off +
316 fpi * TXB_ELEMENT_SIZE + offset);
317 }
318
319 static inline void m_can_config_endisable(const struct m_can_priv *priv,
320 bool enable)
321 {
322 u32 cccr = m_can_read(priv, M_CAN_CCCR);
323 u32 timeout = 10;
324 u32 val = 0;
325
326 if (enable) {
327 /* enable m_can configuration */
328 m_can_write(priv, M_CAN_CCCR, cccr | CCCR_INIT);
329 udelay(5);
330 /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
331 m_can_write(priv, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
332 } else {
333 m_can_write(priv, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
334 }
335
336 /* there's a delay for module initialization */
337 if (enable)
338 val = CCCR_INIT | CCCR_CCE;
339
340 while ((m_can_read(priv, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
341 if (timeout == 0) {
342 netdev_warn(priv->dev, "Failed to init module\n");
343 return;
344 }
345 timeout--;
346 udelay(1);
347 }
348 }
349
350 static inline void m_can_enable_all_interrupts(const struct m_can_priv *priv)
351 {
352 m_can_write(priv, M_CAN_ILE, ILE_EINT0 | ILE_EINT1);
353 }
354
355 static inline void m_can_disable_all_interrupts(const struct m_can_priv *priv)
356 {
357 m_can_write(priv, M_CAN_ILE, 0x0);
358 }
359
360 static void m_can_read_fifo(struct net_device *dev, u32 rxfs)
361 {
362 struct net_device_stats *stats = &dev->stats;
363 struct m_can_priv *priv = netdev_priv(dev);
364 struct canfd_frame *cf;
365 struct sk_buff *skb;
366 u32 id, fgi, dlc;
367 int i;
368
369 /* calculate the fifo get index for where to read data */
370 fgi = (rxfs & RXFS_FGI_MASK) >> RXFS_FGI_OFF;
371 dlc = m_can_fifo_read(priv, fgi, M_CAN_FIFO_DLC);
372 if (dlc & RX_BUF_EDL)
373 skb = alloc_canfd_skb(dev, &cf);
374 else
375 skb = alloc_can_skb(dev, (struct can_frame **)&cf);
376 if (!skb) {
377 stats->rx_dropped++;
378 return;
379 }
380
381 if (dlc & RX_BUF_EDL)
382 cf->len = can_dlc2len((dlc >> 16) & 0x0F);
383 else
384 cf->len = get_can_dlc((dlc >> 16) & 0x0F);
385
386 id = m_can_fifo_read(priv, fgi, M_CAN_FIFO_ID);
387 if (id & RX_BUF_XTD)
388 cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
389 else
390 cf->can_id = (id >> 18) & CAN_SFF_MASK;
391
392 if (id & RX_BUF_ESI) {
393 cf->flags |= CANFD_ESI;
394 netdev_dbg(dev, "ESI Error\n");
395 }
396
397 if (!(dlc & RX_BUF_EDL) && (id & RX_BUF_RTR)) {
398 cf->can_id |= CAN_RTR_FLAG;
399 } else {
400 if (dlc & RX_BUF_BRS)
401 cf->flags |= CANFD_BRS;
402
403 for (i = 0; i < cf->len; i += 4)
404 *(u32 *)(cf->data + i) =
405 m_can_fifo_read(priv, fgi,
406 M_CAN_FIFO_DATA(i / 4));
407 }
408
409 /* acknowledge rx fifo 0 */
410 m_can_write(priv, M_CAN_RXF0A, fgi);
411
412 stats->rx_packets++;
413 stats->rx_bytes += cf->len;
414
415 netif_receive_skb(skb);
416 }
417
418 static int m_can_do_rx_poll(struct net_device *dev, int quota)
419 {
420 struct m_can_priv *priv = netdev_priv(dev);
421 u32 pkts = 0;
422 u32 rxfs;
423
424 rxfs = m_can_read(priv, M_CAN_RXF0S);
425 if (!(rxfs & RXFS_FFL_MASK)) {
426 netdev_dbg(dev, "no messages in fifo0\n");
427 return 0;
428 }
429
430 while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) {
431 if (rxfs & RXFS_RFL)
432 netdev_warn(dev, "Rx FIFO 0 Message Lost\n");
433
434 m_can_read_fifo(dev, rxfs);
435
436 quota--;
437 pkts++;
438 rxfs = m_can_read(priv, M_CAN_RXF0S);
439 }
440
441 if (pkts)
442 can_led_event(dev, CAN_LED_EVENT_RX);
443
444 return pkts;
445 }
446
447 static int m_can_handle_lost_msg(struct net_device *dev)
448 {
449 struct net_device_stats *stats = &dev->stats;
450 struct sk_buff *skb;
451 struct can_frame *frame;
452
453 netdev_err(dev, "msg lost in rxf0\n");
454
455 stats->rx_errors++;
456 stats->rx_over_errors++;
457
458 skb = alloc_can_err_skb(dev, &frame);
459 if (unlikely(!skb))
460 return 0;
461
462 frame->can_id |= CAN_ERR_CRTL;
463 frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
464
465 netif_receive_skb(skb);
466
467 return 1;
468 }
469
470 static int m_can_handle_lec_err(struct net_device *dev,
471 enum m_can_lec_type lec_type)
472 {
473 struct m_can_priv *priv = netdev_priv(dev);
474 struct net_device_stats *stats = &dev->stats;
475 struct can_frame *cf;
476 struct sk_buff *skb;
477
478 priv->can.can_stats.bus_error++;
479 stats->rx_errors++;
480
481 /* propagate the error condition to the CAN stack */
482 skb = alloc_can_err_skb(dev, &cf);
483 if (unlikely(!skb))
484 return 0;
485
486 /* check for 'last error code' which tells us the
487 * type of the last error to occur on the CAN bus
488 */
489 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
490 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
491
492 switch (lec_type) {
493 case LEC_STUFF_ERROR:
494 netdev_dbg(dev, "stuff error\n");
495 cf->data[2] |= CAN_ERR_PROT_STUFF;
496 break;
497 case LEC_FORM_ERROR:
498 netdev_dbg(dev, "form error\n");
499 cf->data[2] |= CAN_ERR_PROT_FORM;
500 break;
501 case LEC_ACK_ERROR:
502 netdev_dbg(dev, "ack error\n");
503 cf->data[3] |= (CAN_ERR_PROT_LOC_ACK |
504 CAN_ERR_PROT_LOC_ACK_DEL);
505 break;
506 case LEC_BIT1_ERROR:
507 netdev_dbg(dev, "bit1 error\n");
508 cf->data[2] |= CAN_ERR_PROT_BIT1;
509 break;
510 case LEC_BIT0_ERROR:
511 netdev_dbg(dev, "bit0 error\n");
512 cf->data[2] |= CAN_ERR_PROT_BIT0;
513 break;
514 case LEC_CRC_ERROR:
515 netdev_dbg(dev, "CRC error\n");
516 cf->data[3] |= (CAN_ERR_PROT_LOC_CRC_SEQ |
517 CAN_ERR_PROT_LOC_CRC_DEL);
518 break;
519 default:
520 break;
521 }
522
523 stats->rx_packets++;
524 stats->rx_bytes += cf->can_dlc;
525 netif_receive_skb(skb);
526
527 return 1;
528 }
529
530 static int __m_can_get_berr_counter(const struct net_device *dev,
531 struct can_berr_counter *bec)
532 {
533 struct m_can_priv *priv = netdev_priv(dev);
534 unsigned int ecr;
535
536 ecr = m_can_read(priv, M_CAN_ECR);
537 bec->rxerr = (ecr & ECR_REC_MASK) >> ECR_REC_SHIFT;
538 bec->txerr = ecr & ECR_TEC_MASK;
539
540 return 0;
541 }
542
543 static int m_can_get_berr_counter(const struct net_device *dev,
544 struct can_berr_counter *bec)
545 {
546 struct m_can_priv *priv = netdev_priv(dev);
547 int err;
548
549 err = clk_prepare_enable(priv->hclk);
550 if (err)
551 return err;
552
553 err = clk_prepare_enable(priv->cclk);
554 if (err) {
555 clk_disable_unprepare(priv->hclk);
556 return err;
557 }
558
559 __m_can_get_berr_counter(dev, bec);
560
561 clk_disable_unprepare(priv->cclk);
562 clk_disable_unprepare(priv->hclk);
563
564 return 0;
565 }
566
567 static int m_can_handle_state_change(struct net_device *dev,
568 enum can_state new_state)
569 {
570 struct m_can_priv *priv = netdev_priv(dev);
571 struct net_device_stats *stats = &dev->stats;
572 struct can_frame *cf;
573 struct sk_buff *skb;
574 struct can_berr_counter bec;
575 unsigned int ecr;
576
577 switch (new_state) {
578 case CAN_STATE_ERROR_ACTIVE:
579 /* error warning state */
580 priv->can.can_stats.error_warning++;
581 priv->can.state = CAN_STATE_ERROR_WARNING;
582 break;
583 case CAN_STATE_ERROR_PASSIVE:
584 /* error passive state */
585 priv->can.can_stats.error_passive++;
586 priv->can.state = CAN_STATE_ERROR_PASSIVE;
587 break;
588 case CAN_STATE_BUS_OFF:
589 /* bus-off state */
590 priv->can.state = CAN_STATE_BUS_OFF;
591 m_can_disable_all_interrupts(priv);
592 can_bus_off(dev);
593 break;
594 default:
595 break;
596 }
597
598 /* propagate the error condition to the CAN stack */
599 skb = alloc_can_err_skb(dev, &cf);
600 if (unlikely(!skb))
601 return 0;
602
603 __m_can_get_berr_counter(dev, &bec);
604
605 switch (new_state) {
606 case CAN_STATE_ERROR_ACTIVE:
607 /* error warning state */
608 cf->can_id |= CAN_ERR_CRTL;
609 cf->data[1] = (bec.txerr > bec.rxerr) ?
610 CAN_ERR_CRTL_TX_WARNING :
611 CAN_ERR_CRTL_RX_WARNING;
612 cf->data[6] = bec.txerr;
613 cf->data[7] = bec.rxerr;
614 break;
615 case CAN_STATE_ERROR_PASSIVE:
616 /* error passive state */
617 cf->can_id |= CAN_ERR_CRTL;
618 ecr = m_can_read(priv, M_CAN_ECR);
619 if (ecr & ECR_RP)
620 cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
621 if (bec.txerr > 127)
622 cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
623 cf->data[6] = bec.txerr;
624 cf->data[7] = bec.rxerr;
625 break;
626 case CAN_STATE_BUS_OFF:
627 /* bus-off state */
628 cf->can_id |= CAN_ERR_BUSOFF;
629 break;
630 default:
631 break;
632 }
633
634 stats->rx_packets++;
635 stats->rx_bytes += cf->can_dlc;
636 netif_receive_skb(skb);
637
638 return 1;
639 }
640
641 static int m_can_handle_state_errors(struct net_device *dev, u32 psr)
642 {
643 struct m_can_priv *priv = netdev_priv(dev);
644 int work_done = 0;
645
646 if ((psr & PSR_EW) &&
647 (priv->can.state != CAN_STATE_ERROR_WARNING)) {
648 netdev_dbg(dev, "entered error warning state\n");
649 work_done += m_can_handle_state_change(dev,
650 CAN_STATE_ERROR_WARNING);
651 }
652
653 if ((psr & PSR_EP) &&
654 (priv->can.state != CAN_STATE_ERROR_PASSIVE)) {
655 netdev_dbg(dev, "entered error passive state\n");
656 work_done += m_can_handle_state_change(dev,
657 CAN_STATE_ERROR_PASSIVE);
658 }
659
660 if ((psr & PSR_BO) &&
661 (priv->can.state != CAN_STATE_BUS_OFF)) {
662 netdev_dbg(dev, "entered error bus off state\n");
663 work_done += m_can_handle_state_change(dev,
664 CAN_STATE_BUS_OFF);
665 }
666
667 return work_done;
668 }
669
670 static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
671 {
672 if (irqstatus & IR_WDI)
673 netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
674 if (irqstatus & IR_ELO)
675 netdev_err(dev, "Error Logging Overflow\n");
676 if (irqstatus & IR_BEU)
677 netdev_err(dev, "Bit Error Uncorrected\n");
678 if (irqstatus & IR_BEC)
679 netdev_err(dev, "Bit Error Corrected\n");
680 if (irqstatus & IR_TOO)
681 netdev_err(dev, "Timeout reached\n");
682 if (irqstatus & IR_MRAF)
683 netdev_err(dev, "Message RAM access failure occurred\n");
684 }
685
686 static inline bool is_lec_err(u32 psr)
687 {
688 psr &= LEC_UNUSED;
689
690 return psr && (psr != LEC_UNUSED);
691 }
692
693 static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
694 u32 psr)
695 {
696 struct m_can_priv *priv = netdev_priv(dev);
697 int work_done = 0;
698
699 if (irqstatus & IR_RF0L)
700 work_done += m_can_handle_lost_msg(dev);
701
702 /* handle lec errors on the bus */
703 if ((priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
704 is_lec_err(psr))
705 work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED);
706
707 /* other unproccessed error interrupts */
708 m_can_handle_other_err(dev, irqstatus);
709
710 return work_done;
711 }
712
713 static int m_can_poll(struct napi_struct *napi, int quota)
714 {
715 struct net_device *dev = napi->dev;
716 struct m_can_priv *priv = netdev_priv(dev);
717 int work_done = 0;
718 u32 irqstatus, psr;
719
720 irqstatus = priv->irqstatus | m_can_read(priv, M_CAN_IR);
721 if (!irqstatus)
722 goto end;
723
724 psr = m_can_read(priv, M_CAN_PSR);
725 if (irqstatus & IR_ERR_STATE)
726 work_done += m_can_handle_state_errors(dev, psr);
727
728 if (irqstatus & IR_ERR_BUS)
729 work_done += m_can_handle_bus_errors(dev, irqstatus, psr);
730
731 if (irqstatus & IR_RF0N)
732 work_done += m_can_do_rx_poll(dev, (quota - work_done));
733
734 if (work_done < quota) {
735 napi_complete(napi);
736 m_can_enable_all_interrupts(priv);
737 }
738
739 end:
740 return work_done;
741 }
742
743 static irqreturn_t m_can_isr(int irq, void *dev_id)
744 {
745 struct net_device *dev = (struct net_device *)dev_id;
746 struct m_can_priv *priv = netdev_priv(dev);
747 struct net_device_stats *stats = &dev->stats;
748 u32 ir;
749
750 ir = m_can_read(priv, M_CAN_IR);
751 if (!ir)
752 return IRQ_NONE;
753
754 /* ACK all irqs */
755 if (ir & IR_ALL_INT)
756 m_can_write(priv, M_CAN_IR, ir);
757
758 /* schedule NAPI in case of
759 * - rx IRQ
760 * - state change IRQ
761 * - bus error IRQ and bus error reporting
762 */
763 if ((ir & IR_RF0N) || (ir & IR_ERR_ALL)) {
764 priv->irqstatus = ir;
765 m_can_disable_all_interrupts(priv);
766 napi_schedule(&priv->napi);
767 }
768
769 /* transmission complete interrupt */
770 if (ir & IR_TC) {
771 stats->tx_bytes += can_get_echo_skb(dev, 0);
772 stats->tx_packets++;
773 can_led_event(dev, CAN_LED_EVENT_TX);
774 netif_wake_queue(dev);
775 }
776
777 return IRQ_HANDLED;
778 }
779
780 static const struct can_bittiming_const m_can_bittiming_const = {
781 .name = KBUILD_MODNAME,
782 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
783 .tseg1_max = 64,
784 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
785 .tseg2_max = 16,
786 .sjw_max = 16,
787 .brp_min = 1,
788 .brp_max = 1024,
789 .brp_inc = 1,
790 };
791
792 static const struct can_bittiming_const m_can_data_bittiming_const = {
793 .name = KBUILD_MODNAME,
794 .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */
795 .tseg1_max = 16,
796 .tseg2_min = 1, /* Time segment 2 = phase_seg2 */
797 .tseg2_max = 8,
798 .sjw_max = 4,
799 .brp_min = 1,
800 .brp_max = 32,
801 .brp_inc = 1,
802 };
803
804 static int m_can_set_bittiming(struct net_device *dev)
805 {
806 struct m_can_priv *priv = netdev_priv(dev);
807 const struct can_bittiming *bt = &priv->can.bittiming;
808 const struct can_bittiming *dbt = &priv->can.data_bittiming;
809 u16 brp, sjw, tseg1, tseg2;
810 u32 reg_btp;
811
812 brp = bt->brp - 1;
813 sjw = bt->sjw - 1;
814 tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
815 tseg2 = bt->phase_seg2 - 1;
816 reg_btp = (brp << BTR_BRP_SHIFT) | (sjw << BTR_SJW_SHIFT) |
817 (tseg1 << BTR_TSEG1_SHIFT) | (tseg2 << BTR_TSEG2_SHIFT);
818 m_can_write(priv, M_CAN_BTP, reg_btp);
819
820 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
821 brp = dbt->brp - 1;
822 sjw = dbt->sjw - 1;
823 tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
824 tseg2 = dbt->phase_seg2 - 1;
825 reg_btp = (brp << FBTR_FBRP_SHIFT) | (sjw << FBTR_FSJW_SHIFT) |
826 (tseg1 << FBTR_FTSEG1_SHIFT) |
827 (tseg2 << FBTR_FTSEG2_SHIFT);
828 m_can_write(priv, M_CAN_FBTP, reg_btp);
829 }
830
831 return 0;
832 }
833
834 /* Configure M_CAN chip:
835 * - set rx buffer/fifo element size
836 * - configure rx fifo
837 * - accept non-matching frame into fifo 0
838 * - configure tx buffer
839 * - configure mode
840 * - setup bittiming
841 */
842 static void m_can_chip_config(struct net_device *dev)
843 {
844 struct m_can_priv *priv = netdev_priv(dev);
845 u32 cccr, test;
846
847 m_can_config_endisable(priv, true);
848
849 /* RX Buffer/FIFO Element Size 64 bytes data field */
850 m_can_write(priv, M_CAN_RXESC, M_CAN_RXESC_64BYTES);
851
852 /* Accept Non-matching Frames Into FIFO 0 */
853 m_can_write(priv, M_CAN_GFC, 0x0);
854
855 /* only support one Tx Buffer currently */
856 m_can_write(priv, M_CAN_TXBC, (1 << TXBC_NDTB_OFF) |
857 priv->mcfg[MRAM_TXB].off);
858
859 /* support 64 bytes payload */
860 m_can_write(priv, M_CAN_TXESC, TXESC_TBDS_64BYTES);
861
862 m_can_write(priv, M_CAN_TXEFC, (1 << TXEFC_EFS_OFF) |
863 priv->mcfg[MRAM_TXE].off);
864
865 /* rx fifo configuration, blocking mode, fifo size 1 */
866 m_can_write(priv, M_CAN_RXF0C,
867 (priv->mcfg[MRAM_RXF0].num << RXFC_FS_OFF) |
868 RXFC_FWM_1 | priv->mcfg[MRAM_RXF0].off);
869
870 m_can_write(priv, M_CAN_RXF1C,
871 (priv->mcfg[MRAM_RXF1].num << RXFC_FS_OFF) |
872 RXFC_FWM_1 | priv->mcfg[MRAM_RXF1].off);
873
874 cccr = m_can_read(priv, M_CAN_CCCR);
875 cccr &= ~(CCCR_TEST | CCCR_MON | (CCCR_CMR_MASK << CCCR_CMR_SHIFT) |
876 (CCCR_CME_MASK << CCCR_CME_SHIFT));
877 test = m_can_read(priv, M_CAN_TEST);
878 test &= ~TEST_LBCK;
879
880 if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
881 cccr |= CCCR_MON;
882
883 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
884 cccr |= CCCR_TEST;
885 test |= TEST_LBCK;
886 }
887
888 if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
889 cccr |= CCCR_CME_CANFD_BRS << CCCR_CME_SHIFT;
890
891 m_can_write(priv, M_CAN_CCCR, cccr);
892 m_can_write(priv, M_CAN_TEST, test);
893
894 /* enable interrupts */
895 m_can_write(priv, M_CAN_IR, IR_ALL_INT);
896 if (!(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
897 m_can_write(priv, M_CAN_IE, IR_ALL_INT & ~IR_ERR_LEC);
898 else
899 m_can_write(priv, M_CAN_IE, IR_ALL_INT);
900
901 /* route all interrupts to INT0 */
902 m_can_write(priv, M_CAN_ILS, ILS_ALL_INT0);
903
904 /* set bittiming params */
905 m_can_set_bittiming(dev);
906
907 m_can_config_endisable(priv, false);
908 }
909
910 static void m_can_start(struct net_device *dev)
911 {
912 struct m_can_priv *priv = netdev_priv(dev);
913
914 /* basic m_can configuration */
915 m_can_chip_config(dev);
916
917 priv->can.state = CAN_STATE_ERROR_ACTIVE;
918
919 m_can_enable_all_interrupts(priv);
920 }
921
922 static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
923 {
924 switch (mode) {
925 case CAN_MODE_START:
926 m_can_start(dev);
927 netif_wake_queue(dev);
928 break;
929 default:
930 return -EOPNOTSUPP;
931 }
932
933 return 0;
934 }
935
936 static void free_m_can_dev(struct net_device *dev)
937 {
938 free_candev(dev);
939 }
940
941 static struct net_device *alloc_m_can_dev(void)
942 {
943 struct net_device *dev;
944 struct m_can_priv *priv;
945
946 dev = alloc_candev(sizeof(*priv), 1);
947 if (!dev)
948 return NULL;
949
950 priv = netdev_priv(dev);
951 netif_napi_add(dev, &priv->napi, m_can_poll, M_CAN_NAPI_WEIGHT);
952
953 priv->dev = dev;
954 priv->can.bittiming_const = &m_can_bittiming_const;
955 priv->can.data_bittiming_const = &m_can_data_bittiming_const;
956 priv->can.do_set_mode = m_can_set_mode;
957 priv->can.do_get_berr_counter = m_can_get_berr_counter;
958 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
959 CAN_CTRLMODE_LISTENONLY |
960 CAN_CTRLMODE_BERR_REPORTING |
961 CAN_CTRLMODE_FD;
962
963 return dev;
964 }
965
966 static int m_can_open(struct net_device *dev)
967 {
968 struct m_can_priv *priv = netdev_priv(dev);
969 int err;
970
971 err = clk_prepare_enable(priv->hclk);
972 if (err)
973 return err;
974
975 err = clk_prepare_enable(priv->cclk);
976 if (err)
977 goto exit_disable_hclk;
978
979 /* open the can device */
980 err = open_candev(dev);
981 if (err) {
982 netdev_err(dev, "failed to open can device\n");
983 goto exit_disable_cclk;
984 }
985
986 /* register interrupt handler */
987 err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
988 dev);
989 if (err < 0) {
990 netdev_err(dev, "failed to request interrupt\n");
991 goto exit_irq_fail;
992 }
993
994 /* start the m_can controller */
995 m_can_start(dev);
996
997 can_led_event(dev, CAN_LED_EVENT_OPEN);
998 napi_enable(&priv->napi);
999 netif_start_queue(dev);
1000
1001 return 0;
1002
1003 exit_irq_fail:
1004 close_candev(dev);
1005 exit_disable_cclk:
1006 clk_disable_unprepare(priv->cclk);
1007 exit_disable_hclk:
1008 clk_disable_unprepare(priv->hclk);
1009 return err;
1010 }
1011
1012 static void m_can_stop(struct net_device *dev)
1013 {
1014 struct m_can_priv *priv = netdev_priv(dev);
1015
1016 /* disable all interrupts */
1017 m_can_disable_all_interrupts(priv);
1018
1019 clk_disable_unprepare(priv->hclk);
1020 clk_disable_unprepare(priv->cclk);
1021
1022 /* set the state as STOPPED */
1023 priv->can.state = CAN_STATE_STOPPED;
1024 }
1025
1026 static int m_can_close(struct net_device *dev)
1027 {
1028 struct m_can_priv *priv = netdev_priv(dev);
1029
1030 netif_stop_queue(dev);
1031 napi_disable(&priv->napi);
1032 m_can_stop(dev);
1033 free_irq(dev->irq, dev);
1034 close_candev(dev);
1035 can_led_event(dev, CAN_LED_EVENT_STOP);
1036
1037 return 0;
1038 }
1039
1040 static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
1041 struct net_device *dev)
1042 {
1043 struct m_can_priv *priv = netdev_priv(dev);
1044 struct canfd_frame *cf = (struct canfd_frame *)skb->data;
1045 u32 id, cccr;
1046 int i;
1047
1048 if (can_dropped_invalid_skb(dev, skb))
1049 return NETDEV_TX_OK;
1050
1051 netif_stop_queue(dev);
1052
1053 if (cf->can_id & CAN_EFF_FLAG) {
1054 id = cf->can_id & CAN_EFF_MASK;
1055 id |= TX_BUF_XTD;
1056 } else {
1057 id = ((cf->can_id & CAN_SFF_MASK) << 18);
1058 }
1059
1060 if (cf->can_id & CAN_RTR_FLAG)
1061 id |= TX_BUF_RTR;
1062
1063 /* message ram configuration */
1064 m_can_fifo_write(priv, 0, M_CAN_FIFO_ID, id);
1065 m_can_fifo_write(priv, 0, M_CAN_FIFO_DLC, can_len2dlc(cf->len) << 16);
1066
1067 for (i = 0; i < cf->len; i += 4)
1068 m_can_fifo_write(priv, 0, M_CAN_FIFO_DATA(i / 4),
1069 *(u32 *)(cf->data + i));
1070
1071 can_put_echo_skb(skb, dev, 0);
1072
1073 if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1074 cccr = m_can_read(priv, M_CAN_CCCR);
1075 cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT);
1076 if (can_is_canfd_skb(skb)) {
1077 if (cf->flags & CANFD_BRS)
1078 cccr |= CCCR_CMR_CANFD_BRS << CCCR_CMR_SHIFT;
1079 else
1080 cccr |= CCCR_CMR_CANFD << CCCR_CMR_SHIFT;
1081 } else {
1082 cccr |= CCCR_CMR_CAN << CCCR_CMR_SHIFT;
1083 }
1084 m_can_write(priv, M_CAN_CCCR, cccr);
1085 }
1086
1087 /* enable first TX buffer to start transfer */
1088 m_can_write(priv, M_CAN_TXBTIE, 0x1);
1089 m_can_write(priv, M_CAN_TXBAR, 0x1);
1090
1091 return NETDEV_TX_OK;
1092 }
1093
1094 static const struct net_device_ops m_can_netdev_ops = {
1095 .ndo_open = m_can_open,
1096 .ndo_stop = m_can_close,
1097 .ndo_start_xmit = m_can_start_xmit,
1098 .ndo_change_mtu = can_change_mtu,
1099 };
1100
1101 static int register_m_can_dev(struct net_device *dev)
1102 {
1103 dev->flags |= IFF_ECHO; /* we support local echo */
1104 dev->netdev_ops = &m_can_netdev_ops;
1105
1106 return register_candev(dev);
1107 }
1108
1109 static int m_can_of_parse_mram(struct platform_device *pdev,
1110 struct m_can_priv *priv)
1111 {
1112 struct device_node *np = pdev->dev.of_node;
1113 struct resource *res;
1114 void __iomem *addr;
1115 u32 out_val[MRAM_CFG_LEN];
1116 int i, start, end, ret;
1117
1118 /* message ram could be shared */
1119 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
1120 if (!res)
1121 return -ENODEV;
1122
1123 addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
1124 if (!addr)
1125 return -ENOMEM;
1126
1127 /* get message ram configuration */
1128 ret = of_property_read_u32_array(np, "bosch,mram-cfg",
1129 out_val, sizeof(out_val) / 4);
1130 if (ret) {
1131 dev_err(&pdev->dev, "can not get message ram configuration\n");
1132 return -ENODEV;
1133 }
1134
1135 priv->mram_base = addr;
1136 priv->mcfg[MRAM_SIDF].off = out_val[0];
1137 priv->mcfg[MRAM_SIDF].num = out_val[1];
1138 priv->mcfg[MRAM_XIDF].off = priv->mcfg[MRAM_SIDF].off +
1139 priv->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE;
1140 priv->mcfg[MRAM_XIDF].num = out_val[2];
1141 priv->mcfg[MRAM_RXF0].off = priv->mcfg[MRAM_XIDF].off +
1142 priv->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE;
1143 priv->mcfg[MRAM_RXF0].num = out_val[3] & RXFC_FS_MASK;
1144 priv->mcfg[MRAM_RXF1].off = priv->mcfg[MRAM_RXF0].off +
1145 priv->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE;
1146 priv->mcfg[MRAM_RXF1].num = out_val[4] & RXFC_FS_MASK;
1147 priv->mcfg[MRAM_RXB].off = priv->mcfg[MRAM_RXF1].off +
1148 priv->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE;
1149 priv->mcfg[MRAM_RXB].num = out_val[5];
1150 priv->mcfg[MRAM_TXE].off = priv->mcfg[MRAM_RXB].off +
1151 priv->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE;
1152 priv->mcfg[MRAM_TXE].num = out_val[6];
1153 priv->mcfg[MRAM_TXB].off = priv->mcfg[MRAM_TXE].off +
1154 priv->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE;
1155 priv->mcfg[MRAM_TXB].num = out_val[7] & TXBC_NDTB_MASK;
1156
1157 dev_dbg(&pdev->dev, "mram_base %p sidf 0x%x %d xidf 0x%x %d rxf0 0x%x %d rxf1 0x%x %d rxb 0x%x %d txe 0x%x %d txb 0x%x %d\n",
1158 priv->mram_base,
1159 priv->mcfg[MRAM_SIDF].off, priv->mcfg[MRAM_SIDF].num,
1160 priv->mcfg[MRAM_XIDF].off, priv->mcfg[MRAM_XIDF].num,
1161 priv->mcfg[MRAM_RXF0].off, priv->mcfg[MRAM_RXF0].num,
1162 priv->mcfg[MRAM_RXF1].off, priv->mcfg[MRAM_RXF1].num,
1163 priv->mcfg[MRAM_RXB].off, priv->mcfg[MRAM_RXB].num,
1164 priv->mcfg[MRAM_TXE].off, priv->mcfg[MRAM_TXE].num,
1165 priv->mcfg[MRAM_TXB].off, priv->mcfg[MRAM_TXB].num);
1166
1167 /* initialize the entire Message RAM in use to avoid possible
1168 * ECC/parity checksum errors when reading an uninitialized buffer
1169 */
1170 start = priv->mcfg[MRAM_SIDF].off;
1171 end = priv->mcfg[MRAM_TXB].off +
1172 priv->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE;
1173 for (i = start; i < end; i += 4)
1174 writel(0x0, priv->mram_base + i);
1175
1176 return 0;
1177 }
1178
1179 static int m_can_plat_probe(struct platform_device *pdev)
1180 {
1181 struct net_device *dev;
1182 struct m_can_priv *priv;
1183 struct resource *res;
1184 void __iomem *addr;
1185 struct clk *hclk, *cclk;
1186 int irq, ret;
1187
1188 hclk = devm_clk_get(&pdev->dev, "hclk");
1189 cclk = devm_clk_get(&pdev->dev, "cclk");
1190 if (IS_ERR(hclk) || IS_ERR(cclk)) {
1191 dev_err(&pdev->dev, "no clock find\n");
1192 return -ENODEV;
1193 }
1194
1195 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "m_can");
1196 addr = devm_ioremap_resource(&pdev->dev, res);
1197 irq = platform_get_irq_byname(pdev, "int0");
1198 if (IS_ERR(addr) || irq < 0)
1199 return -EINVAL;
1200
1201 /* allocate the m_can device */
1202 dev = alloc_m_can_dev();
1203 if (!dev)
1204 return -ENOMEM;
1205
1206 priv = netdev_priv(dev);
1207 dev->irq = irq;
1208 priv->base = addr;
1209 priv->device = &pdev->dev;
1210 priv->hclk = hclk;
1211 priv->cclk = cclk;
1212 priv->can.clock.freq = clk_get_rate(cclk);
1213
1214 ret = m_can_of_parse_mram(pdev, priv);
1215 if (ret)
1216 goto failed_free_dev;
1217
1218 platform_set_drvdata(pdev, dev);
1219 SET_NETDEV_DEV(dev, &pdev->dev);
1220
1221 ret = register_m_can_dev(dev);
1222 if (ret) {
1223 dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
1224 KBUILD_MODNAME, ret);
1225 goto failed_free_dev;
1226 }
1227
1228 devm_can_led_init(dev);
1229
1230 dev_info(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n",
1231 KBUILD_MODNAME, priv->base, dev->irq);
1232
1233 return 0;
1234
1235 failed_free_dev:
1236 free_m_can_dev(dev);
1237 return ret;
1238 }
1239
1240 static __maybe_unused int m_can_suspend(struct device *dev)
1241 {
1242 struct net_device *ndev = dev_get_drvdata(dev);
1243 struct m_can_priv *priv = netdev_priv(ndev);
1244
1245 if (netif_running(ndev)) {
1246 netif_stop_queue(ndev);
1247 netif_device_detach(ndev);
1248 }
1249
1250 /* TODO: enter low power */
1251
1252 priv->can.state = CAN_STATE_SLEEPING;
1253
1254 return 0;
1255 }
1256
1257 static __maybe_unused int m_can_resume(struct device *dev)
1258 {
1259 struct net_device *ndev = dev_get_drvdata(dev);
1260 struct m_can_priv *priv = netdev_priv(ndev);
1261
1262 /* TODO: exit low power */
1263
1264 priv->can.state = CAN_STATE_ERROR_ACTIVE;
1265
1266 if (netif_running(ndev)) {
1267 netif_device_attach(ndev);
1268 netif_start_queue(ndev);
1269 }
1270
1271 return 0;
1272 }
1273
1274 static void unregister_m_can_dev(struct net_device *dev)
1275 {
1276 unregister_candev(dev);
1277 }
1278
1279 static int m_can_plat_remove(struct platform_device *pdev)
1280 {
1281 struct net_device *dev = platform_get_drvdata(pdev);
1282
1283 unregister_m_can_dev(dev);
1284 platform_set_drvdata(pdev, NULL);
1285
1286 free_m_can_dev(dev);
1287
1288 return 0;
1289 }
1290
1291 static const struct dev_pm_ops m_can_pmops = {
1292 SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
1293 };
1294
1295 static const struct of_device_id m_can_of_table[] = {
1296 { .compatible = "bosch,m_can", .data = NULL },
1297 { /* sentinel */ },
1298 };
1299 MODULE_DEVICE_TABLE(of, m_can_of_table);
1300
1301 static struct platform_driver m_can_plat_driver = {
1302 .driver = {
1303 .name = KBUILD_MODNAME,
1304 .of_match_table = m_can_of_table,
1305 .pm = &m_can_pmops,
1306 },
1307 .probe = m_can_plat_probe,
1308 .remove = m_can_plat_remove,
1309 };
1310
1311 module_platform_driver(m_can_plat_driver);
1312
1313 MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
1314 MODULE_LICENSE("GPL v2");
1315 MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");
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