1/*
2 * flexcan.c - FLEXCAN CAN controller driver
3 *
4 * Copyright (c) 2005-2006 Varma Electronics Oy
5 * Copyright (c) 2009 Sascha Hauer, Pengutronix
6 * Copyright (c) 2010 Marc Kleine-Budde, Pengutronix
7 *
8 * Based on code originally by Andrey Volkov <avolkov@varma-el.com>
9 *
10 * LICENCE:
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation version 2.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 */
21
22#include <linux/netdevice.h>
23#include <linux/can.h>
24#include <linux/can/dev.h>
25#include <linux/can/error.h>
26#include <linux/can/led.h>
27#include <linux/clk.h>
28#include <linux/delay.h>
29#include <linux/if_arp.h>
30#include <linux/if_ether.h>
31#include <linux/interrupt.h>
32#include <linux/io.h>
33#include <linux/kernel.h>
34#include <linux/list.h>
35#include <linux/module.h>
36#include <linux/of.h>
37#include <linux/of_device.h>
38#include <linux/platform_device.h>
39#include <linux/regulator/consumer.h>
40
41#define DRV_NAME			"flexcan"
42
43/* 8 for RX fifo and 2 error handling */
44#define FLEXCAN_NAPI_WEIGHT		(8 + 2)
45
46/* FLEXCAN module configuration register (CANMCR) bits */
47#define FLEXCAN_MCR_MDIS		BIT(31)
48#define FLEXCAN_MCR_FRZ			BIT(30)
49#define FLEXCAN_MCR_FEN			BIT(29)
50#define FLEXCAN_MCR_HALT		BIT(28)
51#define FLEXCAN_MCR_NOT_RDY		BIT(27)
52#define FLEXCAN_MCR_WAK_MSK		BIT(26)
53#define FLEXCAN_MCR_SOFTRST		BIT(25)
54#define FLEXCAN_MCR_FRZ_ACK		BIT(24)
55#define FLEXCAN_MCR_SUPV		BIT(23)
56#define FLEXCAN_MCR_SLF_WAK		BIT(22)
57#define FLEXCAN_MCR_WRN_EN		BIT(21)
58#define FLEXCAN_MCR_LPM_ACK		BIT(20)
59#define FLEXCAN_MCR_WAK_SRC		BIT(19)
60#define FLEXCAN_MCR_DOZE		BIT(18)
61#define FLEXCAN_MCR_SRX_DIS		BIT(17)
62#define FLEXCAN_MCR_BCC			BIT(16)
63#define FLEXCAN_MCR_LPRIO_EN		BIT(13)
64#define FLEXCAN_MCR_AEN			BIT(12)
65#define FLEXCAN_MCR_MAXMB(x)		((x) & 0x7f)
66#define FLEXCAN_MCR_IDAM_A		(0 << 8)
67#define FLEXCAN_MCR_IDAM_B		(1 << 8)
68#define FLEXCAN_MCR_IDAM_C		(2 << 8)
69#define FLEXCAN_MCR_IDAM_D		(3 << 8)
70
71/* FLEXCAN control register (CANCTRL) bits */
72#define FLEXCAN_CTRL_PRESDIV(x)		(((x) & 0xff) << 24)
73#define FLEXCAN_CTRL_RJW(x)		(((x) & 0x03) << 22)
74#define FLEXCAN_CTRL_PSEG1(x)		(((x) & 0x07) << 19)
75#define FLEXCAN_CTRL_PSEG2(x)		(((x) & 0x07) << 16)
76#define FLEXCAN_CTRL_BOFF_MSK		BIT(15)
77#define FLEXCAN_CTRL_ERR_MSK		BIT(14)
78#define FLEXCAN_CTRL_CLK_SRC		BIT(13)
79#define FLEXCAN_CTRL_LPB		BIT(12)
80#define FLEXCAN_CTRL_TWRN_MSK		BIT(11)
81#define FLEXCAN_CTRL_RWRN_MSK		BIT(10)
82#define FLEXCAN_CTRL_SMP		BIT(7)
83#define FLEXCAN_CTRL_BOFF_REC		BIT(6)
84#define FLEXCAN_CTRL_TSYN		BIT(5)
85#define FLEXCAN_CTRL_LBUF		BIT(4)
86#define FLEXCAN_CTRL_LOM		BIT(3)
87#define FLEXCAN_CTRL_PROPSEG(x)		((x) & 0x07)
88#define FLEXCAN_CTRL_ERR_BUS		(FLEXCAN_CTRL_ERR_MSK)
89#define FLEXCAN_CTRL_ERR_STATE \
90	(FLEXCAN_CTRL_TWRN_MSK | FLEXCAN_CTRL_RWRN_MSK | \
91	 FLEXCAN_CTRL_BOFF_MSK)
92#define FLEXCAN_CTRL_ERR_ALL \
93	(FLEXCAN_CTRL_ERR_BUS | FLEXCAN_CTRL_ERR_STATE)
94
95/* FLEXCAN control register 2 (CTRL2) bits */
96#define FLEXCAN_CRL2_ECRWRE		BIT(29)
97#define FLEXCAN_CRL2_WRMFRZ		BIT(28)
98#define FLEXCAN_CRL2_RFFN(x)		(((x) & 0x0f) << 24)
99#define FLEXCAN_CRL2_TASD(x)		(((x) & 0x1f) << 19)
100#define FLEXCAN_CRL2_MRP		BIT(18)
101#define FLEXCAN_CRL2_RRS		BIT(17)
102#define FLEXCAN_CRL2_EACEN		BIT(16)
103
104/* FLEXCAN memory error control register (MECR) bits */
105#define FLEXCAN_MECR_ECRWRDIS		BIT(31)
106#define FLEXCAN_MECR_HANCEI_MSK		BIT(19)
107#define FLEXCAN_MECR_FANCEI_MSK		BIT(18)
108#define FLEXCAN_MECR_CEI_MSK		BIT(16)
109#define FLEXCAN_MECR_HAERRIE		BIT(15)
110#define FLEXCAN_MECR_FAERRIE		BIT(14)
111#define FLEXCAN_MECR_EXTERRIE		BIT(13)
112#define FLEXCAN_MECR_RERRDIS		BIT(9)
113#define FLEXCAN_MECR_ECCDIS		BIT(8)
114#define FLEXCAN_MECR_NCEFAFRZ		BIT(7)
115
116/* FLEXCAN error and status register (ESR) bits */
117#define FLEXCAN_ESR_TWRN_INT		BIT(17)
118#define FLEXCAN_ESR_RWRN_INT		BIT(16)
119#define FLEXCAN_ESR_BIT1_ERR		BIT(15)
120#define FLEXCAN_ESR_BIT0_ERR		BIT(14)
121#define FLEXCAN_ESR_ACK_ERR		BIT(13)
122#define FLEXCAN_ESR_CRC_ERR		BIT(12)
123#define FLEXCAN_ESR_FRM_ERR		BIT(11)
124#define FLEXCAN_ESR_STF_ERR		BIT(10)
125#define FLEXCAN_ESR_TX_WRN		BIT(9)
126#define FLEXCAN_ESR_RX_WRN		BIT(8)
127#define FLEXCAN_ESR_IDLE		BIT(7)
128#define FLEXCAN_ESR_TXRX		BIT(6)
129#define FLEXCAN_EST_FLT_CONF_SHIFT	(4)
130#define FLEXCAN_ESR_FLT_CONF_MASK	(0x3 << FLEXCAN_EST_FLT_CONF_SHIFT)
131#define FLEXCAN_ESR_FLT_CONF_ACTIVE	(0x0 << FLEXCAN_EST_FLT_CONF_SHIFT)
132#define FLEXCAN_ESR_FLT_CONF_PASSIVE	(0x1 << FLEXCAN_EST_FLT_CONF_SHIFT)
133#define FLEXCAN_ESR_BOFF_INT		BIT(2)
134#define FLEXCAN_ESR_ERR_INT		BIT(1)
135#define FLEXCAN_ESR_WAK_INT		BIT(0)
136#define FLEXCAN_ESR_ERR_BUS \
137	(FLEXCAN_ESR_BIT1_ERR | FLEXCAN_ESR_BIT0_ERR | \
138	 FLEXCAN_ESR_ACK_ERR | FLEXCAN_ESR_CRC_ERR | \
139	 FLEXCAN_ESR_FRM_ERR | FLEXCAN_ESR_STF_ERR)
140#define FLEXCAN_ESR_ERR_STATE \
141	(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT)
142#define FLEXCAN_ESR_ERR_ALL \
143	(FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
144#define FLEXCAN_ESR_ALL_INT \
145	(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
146	 FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT)
147
148/* FLEXCAN interrupt flag register (IFLAG) bits */
149/* Errata ERR005829 step7: Reserve first valid MB */
150#define FLEXCAN_TX_BUF_RESERVED		8
151#define FLEXCAN_TX_BUF_ID		9
152#define FLEXCAN_IFLAG_BUF(x)		BIT(x)
153#define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW	BIT(7)
154#define FLEXCAN_IFLAG_RX_FIFO_WARN	BIT(6)
155#define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE	BIT(5)
156#define FLEXCAN_IFLAG_DEFAULT \
157	(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW | FLEXCAN_IFLAG_RX_FIFO_AVAILABLE | \
158	 FLEXCAN_IFLAG_BUF(FLEXCAN_TX_BUF_ID))
159
160/* FLEXCAN message buffers */
161#define FLEXCAN_MB_CNT_CODE(x)		(((x) & 0xf) << 24)
162#define FLEXCAN_MB_CODE_RX_INACTIVE	(0x0 << 24)
163#define FLEXCAN_MB_CODE_RX_EMPTY	(0x4 << 24)
164#define FLEXCAN_MB_CODE_RX_FULL		(0x2 << 24)
165#define FLEXCAN_MB_CODE_RX_OVERRRUN	(0x6 << 24)
166#define FLEXCAN_MB_CODE_RX_RANSWER	(0xa << 24)
167
168#define FLEXCAN_MB_CODE_TX_INACTIVE	(0x8 << 24)
169#define FLEXCAN_MB_CODE_TX_ABORT	(0x9 << 24)
170#define FLEXCAN_MB_CODE_TX_DATA		(0xc << 24)
171#define FLEXCAN_MB_CODE_TX_TANSWER	(0xe << 24)
172
173#define FLEXCAN_MB_CNT_SRR		BIT(22)
174#define FLEXCAN_MB_CNT_IDE		BIT(21)
175#define FLEXCAN_MB_CNT_RTR		BIT(20)
176#define FLEXCAN_MB_CNT_LENGTH(x)	(((x) & 0xf) << 16)
177#define FLEXCAN_MB_CNT_TIMESTAMP(x)	((x) & 0xffff)
178
179#define FLEXCAN_MB_CODE_MASK		(0xf0ffffff)
180
181#define FLEXCAN_TIMEOUT_US             (50)
182
183/*
184 * FLEXCAN hardware feature flags
185 *
186 * Below is some version info we got:
187 *    SOC   Version   IP-Version  Glitch-  [TR]WRN_INT  Memory err
188 *                                Filter?   connected?  detection
189 *   MX25  FlexCAN2  03.00.00.00     no         no         no
190 *   MX28  FlexCAN2  03.00.04.00    yes        yes         no
191 *   MX35  FlexCAN2  03.00.00.00     no         no         no
192 *   MX53  FlexCAN2  03.00.00.00    yes         no         no
193 *   MX6s  FlexCAN3  10.00.12.00    yes        yes         no
194 *   VF610 FlexCAN3  ?               no        yes        yes
195 *
196 * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
197 */
198#define FLEXCAN_HAS_V10_FEATURES	BIT(1) /* For core version >= 10 */
199#define FLEXCAN_HAS_BROKEN_ERR_STATE	BIT(2) /* [TR]WRN_INT not connected */
200#define FLEXCAN_HAS_MECR_FEATURES	BIT(3) /* Memory error detection */
201
202/* Structure of the message buffer */
203struct flexcan_mb {
204	u32 can_ctrl;
205	u32 can_id;
206	u32 data[2];
207};
208
209/* Structure of the hardware registers */
210struct flexcan_regs {
211	u32 mcr;		/* 0x00 */
212	u32 ctrl;		/* 0x04 */
213	u32 timer;		/* 0x08 */
214	u32 _reserved1;		/* 0x0c */
215	u32 rxgmask;		/* 0x10 */
216	u32 rx14mask;		/* 0x14 */
217	u32 rx15mask;		/* 0x18 */
218	u32 ecr;		/* 0x1c */
219	u32 esr;		/* 0x20 */
220	u32 imask2;		/* 0x24 */
221	u32 imask1;		/* 0x28 */
222	u32 iflag2;		/* 0x2c */
223	u32 iflag1;		/* 0x30 */
224	u32 crl2;		/* 0x34 */
225	u32 esr2;		/* 0x38 */
226	u32 imeur;		/* 0x3c */
227	u32 lrfr;		/* 0x40 */
228	u32 crcr;		/* 0x44 */
229	u32 rxfgmask;		/* 0x48 */
230	u32 rxfir;		/* 0x4c */
231	u32 _reserved3[12];	/* 0x50 */
232	struct flexcan_mb cantxfg[64];	/* 0x80 */
233	u32 _reserved4[408];
234	u32 mecr;		/* 0xae0 */
235	u32 erriar;		/* 0xae4 */
236	u32 erridpr;		/* 0xae8 */
237	u32 errippr;		/* 0xaec */
238	u32 rerrar;		/* 0xaf0 */
239	u32 rerrdr;		/* 0xaf4 */
240	u32 rerrsynr;		/* 0xaf8 */
241	u32 errsr;		/* 0xafc */
242};
243
244struct flexcan_devtype_data {
245	u32 features;	/* hardware controller features */
246};
247
248struct flexcan_priv {
249	struct can_priv can;
250	struct napi_struct napi;
251
252	void __iomem *base;
253	u32 reg_esr;
254	u32 reg_ctrl_default;
255
256	struct clk *clk_ipg;
257	struct clk *clk_per;
258	struct flexcan_platform_data *pdata;
259	const struct flexcan_devtype_data *devtype_data;
260	struct regulator *reg_xceiver;
261};
262
263static struct flexcan_devtype_data fsl_p1010_devtype_data = {
264	.features = FLEXCAN_HAS_BROKEN_ERR_STATE,
265};
266static struct flexcan_devtype_data fsl_imx28_devtype_data;
267static struct flexcan_devtype_data fsl_imx6q_devtype_data = {
268	.features = FLEXCAN_HAS_V10_FEATURES,
269};
270static struct flexcan_devtype_data fsl_vf610_devtype_data = {
271	.features = FLEXCAN_HAS_V10_FEATURES | FLEXCAN_HAS_MECR_FEATURES,
272};
273
274static const struct can_bittiming_const flexcan_bittiming_const = {
275	.name = DRV_NAME,
276	.tseg1_min = 4,
277	.tseg1_max = 16,
278	.tseg2_min = 2,
279	.tseg2_max = 8,
280	.sjw_max = 4,
281	.brp_min = 1,
282	.brp_max = 256,
283	.brp_inc = 1,
284};
285
286/*
287 * Abstract off the read/write for arm versus ppc. This
288 * assumes that PPC uses big-endian registers and everything
289 * else uses little-endian registers, independent of CPU
290 * endianess.
291 */
292#if defined(CONFIG_PPC)
293static inline u32 flexcan_read(void __iomem *addr)
294{
295	return in_be32(addr);
296}
297
298static inline void flexcan_write(u32 val, void __iomem *addr)
299{
300	out_be32(addr, val);
301}
302#else
303static inline u32 flexcan_read(void __iomem *addr)
304{
305	return readl(addr);
306}
307
308static inline void flexcan_write(u32 val, void __iomem *addr)
309{
310	writel(val, addr);
311}
312#endif
313
314static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
315{
316	if (!priv->reg_xceiver)
317		return 0;
318
319	return regulator_enable(priv->reg_xceiver);
320}
321
322static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
323{
324	if (!priv->reg_xceiver)
325		return 0;
326
327	return regulator_disable(priv->reg_xceiver);
328}
329
330static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv,
331					      u32 reg_esr)
332{
333	return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
334		(reg_esr & FLEXCAN_ESR_ERR_BUS);
335}
336
337static int flexcan_chip_enable(struct flexcan_priv *priv)
338{
339	struct flexcan_regs __iomem *regs = priv->base;
340	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
341	u32 reg;
342
343	reg = flexcan_read(&regs->mcr);
344	reg &= ~FLEXCAN_MCR_MDIS;
345	flexcan_write(reg, &regs->mcr);
346
347	while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
348		udelay(10);
349
350	if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
351		return -ETIMEDOUT;
352
353	return 0;
354}
355
356static int flexcan_chip_disable(struct flexcan_priv *priv)
357{
358	struct flexcan_regs __iomem *regs = priv->base;
359	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
360	u32 reg;
361
362	reg = flexcan_read(&regs->mcr);
363	reg |= FLEXCAN_MCR_MDIS;
364	flexcan_write(reg, &regs->mcr);
365
366	while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
367		udelay(10);
368
369	if (!(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
370		return -ETIMEDOUT;
371
372	return 0;
373}
374
375static int flexcan_chip_freeze(struct flexcan_priv *priv)
376{
377	struct flexcan_regs __iomem *regs = priv->base;
378	unsigned int timeout = 1000 * 1000 * 10 / priv->can.bittiming.bitrate;
379	u32 reg;
380
381	reg = flexcan_read(&regs->mcr);
382	reg |= FLEXCAN_MCR_HALT;
383	flexcan_write(reg, &regs->mcr);
384
385	while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
386		udelay(100);
387
388	if (!(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
389		return -ETIMEDOUT;
390
391	return 0;
392}
393
394static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
395{
396	struct flexcan_regs __iomem *regs = priv->base;
397	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
398	u32 reg;
399
400	reg = flexcan_read(&regs->mcr);
401	reg &= ~FLEXCAN_MCR_HALT;
402	flexcan_write(reg, &regs->mcr);
403
404	while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
405		udelay(10);
406
407	if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
408		return -ETIMEDOUT;
409
410	return 0;
411}
412
413static int flexcan_chip_softreset(struct flexcan_priv *priv)
414{
415	struct flexcan_regs __iomem *regs = priv->base;
416	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
417
418	flexcan_write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
419	while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
420		udelay(10);
421
422	if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
423		return -ETIMEDOUT;
424
425	return 0;
426}
427
428
429static int __flexcan_get_berr_counter(const struct net_device *dev,
430				      struct can_berr_counter *bec)
431{
432	const struct flexcan_priv *priv = netdev_priv(dev);
433	struct flexcan_regs __iomem *regs = priv->base;
434	u32 reg = flexcan_read(&regs->ecr);
435
436	bec->txerr = (reg >> 0) & 0xff;
437	bec->rxerr = (reg >> 8) & 0xff;
438
439	return 0;
440}
441
442static int flexcan_get_berr_counter(const struct net_device *dev,
443				    struct can_berr_counter *bec)
444{
445	const struct flexcan_priv *priv = netdev_priv(dev);
446	int err;
447
448	err = clk_prepare_enable(priv->clk_ipg);
449	if (err)
450		return err;
451
452	err = clk_prepare_enable(priv->clk_per);
453	if (err)
454		goto out_disable_ipg;
455
456	err = __flexcan_get_berr_counter(dev, bec);
457
458	clk_disable_unprepare(priv->clk_per);
459 out_disable_ipg:
460	clk_disable_unprepare(priv->clk_ipg);
461
462	return err;
463}
464
465static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
466{
467	const struct flexcan_priv *priv = netdev_priv(dev);
468	struct flexcan_regs __iomem *regs = priv->base;
469	struct can_frame *cf = (struct can_frame *)skb->data;
470	u32 can_id;
471	u32 ctrl = FLEXCAN_MB_CNT_CODE(0xc) | (cf->can_dlc << 16);
472
473	if (can_dropped_invalid_skb(dev, skb))
474		return NETDEV_TX_OK;
475
476	netif_stop_queue(dev);
477
478	if (cf->can_id & CAN_EFF_FLAG) {
479		can_id = cf->can_id & CAN_EFF_MASK;
480		ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
481	} else {
482		can_id = (cf->can_id & CAN_SFF_MASK) << 18;
483	}
484
485	if (cf->can_id & CAN_RTR_FLAG)
486		ctrl |= FLEXCAN_MB_CNT_RTR;
487
488	if (cf->can_dlc > 0) {
489		u32 data = be32_to_cpup((__be32 *)&cf->data[0]);
490		flexcan_write(data, &regs->cantxfg[FLEXCAN_TX_BUF_ID].data[0]);
491	}
492	if (cf->can_dlc > 3) {
493		u32 data = be32_to_cpup((__be32 *)&cf->data[4]);
494		flexcan_write(data, &regs->cantxfg[FLEXCAN_TX_BUF_ID].data[1]);
495	}
496
497	can_put_echo_skb(skb, dev, 0);
498
499	flexcan_write(can_id, &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_id);
500	flexcan_write(ctrl, &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
501
502	/* Errata ERR005829 step8:
503	 * Write twice INACTIVE(0x8) code to first MB.
504	 */
505	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
506		      &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
507	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
508		      &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
509
510	return NETDEV_TX_OK;
511}
512
513static void do_bus_err(struct net_device *dev,
514		       struct can_frame *cf, u32 reg_esr)
515{
516	struct flexcan_priv *priv = netdev_priv(dev);
517	int rx_errors = 0, tx_errors = 0;
518
519	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
520
521	if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
522		netdev_dbg(dev, "BIT1_ERR irq\n");
523		cf->data[2] |= CAN_ERR_PROT_BIT1;
524		tx_errors = 1;
525	}
526	if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
527		netdev_dbg(dev, "BIT0_ERR irq\n");
528		cf->data[2] |= CAN_ERR_PROT_BIT0;
529		tx_errors = 1;
530	}
531	if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
532		netdev_dbg(dev, "ACK_ERR irq\n");
533		cf->can_id |= CAN_ERR_ACK;
534		cf->data[3] |= CAN_ERR_PROT_LOC_ACK;
535		tx_errors = 1;
536	}
537	if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
538		netdev_dbg(dev, "CRC_ERR irq\n");
539		cf->data[2] |= CAN_ERR_PROT_BIT;
540		cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
541		rx_errors = 1;
542	}
543	if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
544		netdev_dbg(dev, "FRM_ERR irq\n");
545		cf->data[2] |= CAN_ERR_PROT_FORM;
546		rx_errors = 1;
547	}
548	if (reg_esr & FLEXCAN_ESR_STF_ERR) {
549		netdev_dbg(dev, "STF_ERR irq\n");
550		cf->data[2] |= CAN_ERR_PROT_STUFF;
551		rx_errors = 1;
552	}
553
554	priv->can.can_stats.bus_error++;
555	if (rx_errors)
556		dev->stats.rx_errors++;
557	if (tx_errors)
558		dev->stats.tx_errors++;
559}
560
561static int flexcan_poll_bus_err(struct net_device *dev, u32 reg_esr)
562{
563	struct sk_buff *skb;
564	struct can_frame *cf;
565
566	skb = alloc_can_err_skb(dev, &cf);
567	if (unlikely(!skb))
568		return 0;
569
570	do_bus_err(dev, cf, reg_esr);
571	netif_receive_skb(skb);
572
573	dev->stats.rx_packets++;
574	dev->stats.rx_bytes += cf->can_dlc;
575
576	return 1;
577}
578
579static int flexcan_poll_state(struct net_device *dev, u32 reg_esr)
580{
581	struct flexcan_priv *priv = netdev_priv(dev);
582	struct sk_buff *skb;
583	struct can_frame *cf;
584	enum can_state new_state = 0, rx_state = 0, tx_state = 0;
585	int flt;
586	struct can_berr_counter bec;
587
588	flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
589	if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
590		tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
591			   CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
592		rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
593			   CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
594		new_state = max(tx_state, rx_state);
595	} else {
596		__flexcan_get_berr_counter(dev, &bec);
597		new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
598			    CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
599		rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
600		tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
601	}
602
603	/* state hasn't changed */
604	if (likely(new_state == priv->can.state))
605		return 0;
606
607	skb = alloc_can_err_skb(dev, &cf);
608	if (unlikely(!skb))
609		return 0;
610
611	can_change_state(dev, cf, tx_state, rx_state);
612
613	if (unlikely(new_state == CAN_STATE_BUS_OFF))
614		can_bus_off(dev);
615
616	netif_receive_skb(skb);
617
618	dev->stats.rx_packets++;
619	dev->stats.rx_bytes += cf->can_dlc;
620
621	return 1;
622}
623
624static void flexcan_read_fifo(const struct net_device *dev,
625			      struct can_frame *cf)
626{
627	const struct flexcan_priv *priv = netdev_priv(dev);
628	struct flexcan_regs __iomem *regs = priv->base;
629	struct flexcan_mb __iomem *mb = &regs->cantxfg[0];
630	u32 reg_ctrl, reg_id;
631
632	reg_ctrl = flexcan_read(&mb->can_ctrl);
633	reg_id = flexcan_read(&mb->can_id);
634	if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
635		cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
636	else
637		cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;
638
639	if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
640		cf->can_id |= CAN_RTR_FLAG;
641	cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);
642
643	*(__be32 *)(cf->data + 0) = cpu_to_be32(flexcan_read(&mb->data[0]));
644	*(__be32 *)(cf->data + 4) = cpu_to_be32(flexcan_read(&mb->data[1]));
645
646	/* mark as read */
647	flexcan_write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
648	flexcan_read(&regs->timer);
649}
650
651static int flexcan_read_frame(struct net_device *dev)
652{
653	struct net_device_stats *stats = &dev->stats;
654	struct can_frame *cf;
655	struct sk_buff *skb;
656
657	skb = alloc_can_skb(dev, &cf);
658	if (unlikely(!skb)) {
659		stats->rx_dropped++;
660		return 0;
661	}
662
663	flexcan_read_fifo(dev, cf);
664	netif_receive_skb(skb);
665
666	stats->rx_packets++;
667	stats->rx_bytes += cf->can_dlc;
668
669	can_led_event(dev, CAN_LED_EVENT_RX);
670
671	return 1;
672}
673
674static int flexcan_poll(struct napi_struct *napi, int quota)
675{
676	struct net_device *dev = napi->dev;
677	const struct flexcan_priv *priv = netdev_priv(dev);
678	struct flexcan_regs __iomem *regs = priv->base;
679	u32 reg_iflag1, reg_esr;
680	int work_done = 0;
681
682	/*
683	 * The error bits are cleared on read,
684	 * use saved value from irq handler.
685	 */
686	reg_esr = flexcan_read(&regs->esr) | priv->reg_esr;
687
688	/* handle state changes */
689	work_done += flexcan_poll_state(dev, reg_esr);
690
691	/* handle RX-FIFO */
692	reg_iflag1 = flexcan_read(&regs->iflag1);
693	while (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE &&
694	       work_done < quota) {
695		work_done += flexcan_read_frame(dev);
696		reg_iflag1 = flexcan_read(&regs->iflag1);
697	}
698
699	/* report bus errors */
700	if (flexcan_has_and_handle_berr(priv, reg_esr) && work_done < quota)
701		work_done += flexcan_poll_bus_err(dev, reg_esr);
702
703	if (work_done < quota) {
704		napi_complete(napi);
705		/* enable IRQs */
706		flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
707		flexcan_write(priv->reg_ctrl_default, &regs->ctrl);
708	}
709
710	return work_done;
711}
712
713static irqreturn_t flexcan_irq(int irq, void *dev_id)
714{
715	struct net_device *dev = dev_id;
716	struct net_device_stats *stats = &dev->stats;
717	struct flexcan_priv *priv = netdev_priv(dev);
718	struct flexcan_regs __iomem *regs = priv->base;
719	u32 reg_iflag1, reg_esr;
720
721	reg_iflag1 = flexcan_read(&regs->iflag1);
722	reg_esr = flexcan_read(&regs->esr);
723	/* ACK all bus error and state change IRQ sources */
724	if (reg_esr & FLEXCAN_ESR_ALL_INT)
725		flexcan_write(reg_esr & FLEXCAN_ESR_ALL_INT, &regs->esr);
726
727	/*
728	 * schedule NAPI in case of:
729	 * - rx IRQ
730	 * - state change IRQ
731	 * - bus error IRQ and bus error reporting is activated
732	 */
733	if ((reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) ||
734	    (reg_esr & FLEXCAN_ESR_ERR_STATE) ||
735	    flexcan_has_and_handle_berr(priv, reg_esr)) {
736		/*
737		 * The error bits are cleared on read,
738		 * save them for later use.
739		 */
740		priv->reg_esr = reg_esr & FLEXCAN_ESR_ERR_BUS;
741		flexcan_write(FLEXCAN_IFLAG_DEFAULT &
742			~FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->imask1);
743		flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
744		       &regs->ctrl);
745		napi_schedule(&priv->napi);
746	}
747
748	/* FIFO overflow */
749	if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
750		flexcan_write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW, &regs->iflag1);
751		dev->stats.rx_over_errors++;
752		dev->stats.rx_errors++;
753	}
754
755	/* transmission complete interrupt */
756	if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
757		stats->tx_bytes += can_get_echo_skb(dev, 0);
758		stats->tx_packets++;
759		can_led_event(dev, CAN_LED_EVENT_TX);
760		/* after sending a RTR frame mailbox is in RX mode */
761		flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
762			      &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
763		flexcan_write((1 << FLEXCAN_TX_BUF_ID), &regs->iflag1);
764		netif_wake_queue(dev);
765	}
766
767	return IRQ_HANDLED;
768}
769
770static void flexcan_set_bittiming(struct net_device *dev)
771{
772	const struct flexcan_priv *priv = netdev_priv(dev);
773	const struct can_bittiming *bt = &priv->can.bittiming;
774	struct flexcan_regs __iomem *regs = priv->base;
775	u32 reg;
776
777	reg = flexcan_read(&regs->ctrl);
778	reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
779		 FLEXCAN_CTRL_RJW(0x3) |
780		 FLEXCAN_CTRL_PSEG1(0x7) |
781		 FLEXCAN_CTRL_PSEG2(0x7) |
782		 FLEXCAN_CTRL_PROPSEG(0x7) |
783		 FLEXCAN_CTRL_LPB |
784		 FLEXCAN_CTRL_SMP |
785		 FLEXCAN_CTRL_LOM);
786
787	reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
788		FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
789		FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
790		FLEXCAN_CTRL_RJW(bt->sjw - 1) |
791		FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
792
793	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
794		reg |= FLEXCAN_CTRL_LPB;
795	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
796		reg |= FLEXCAN_CTRL_LOM;
797	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
798		reg |= FLEXCAN_CTRL_SMP;
799
800	netdev_info(dev, "writing ctrl=0x%08x\n", reg);
801	flexcan_write(reg, &regs->ctrl);
802
803	/* print chip status */
804	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
805		   flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
806}
807
808/*
809 * flexcan_chip_start
810 *
811 * this functions is entered with clocks enabled
812 *
813 */
814static int flexcan_chip_start(struct net_device *dev)
815{
816	struct flexcan_priv *priv = netdev_priv(dev);
817	struct flexcan_regs __iomem *regs = priv->base;
818	u32 reg_mcr, reg_ctrl, reg_crl2, reg_mecr;
819	int err, i;
820
821	/* enable module */
822	err = flexcan_chip_enable(priv);
823	if (err)
824		return err;
825
826	/* soft reset */
827	err = flexcan_chip_softreset(priv);
828	if (err)
829		goto out_chip_disable;
830
831	flexcan_set_bittiming(dev);
832
833	/*
834	 * MCR
835	 *
836	 * enable freeze
837	 * enable fifo
838	 * halt now
839	 * only supervisor access
840	 * enable warning int
841	 * choose format C
842	 * disable local echo
843	 *
844	 */
845	reg_mcr = flexcan_read(&regs->mcr);
846	reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
847	reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT |
848		FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN |
849		FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS |
850		FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID);
851	netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
852	flexcan_write(reg_mcr, &regs->mcr);
853
854	/*
855	 * CTRL
856	 *
857	 * disable timer sync feature
858	 *
859	 * disable auto busoff recovery
860	 * transmit lowest buffer first
861	 *
862	 * enable tx and rx warning interrupt
863	 * enable bus off interrupt
864	 * (== FLEXCAN_CTRL_ERR_STATE)
865	 */
866	reg_ctrl = flexcan_read(&regs->ctrl);
867	reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
868	reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
869		FLEXCAN_CTRL_ERR_STATE;
870	/*
871	 * enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
872	 * on most Flexcan cores, too. Otherwise we don't get
873	 * any error warning or passive interrupts.
874	 */
875	if (priv->devtype_data->features & FLEXCAN_HAS_BROKEN_ERR_STATE ||
876	    priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
877		reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
878	else
879		reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
880
881	/* save for later use */
882	priv->reg_ctrl_default = reg_ctrl;
883	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
884	flexcan_write(reg_ctrl, &regs->ctrl);
885
886	/* clear and invalidate all mailboxes first */
887	for (i = FLEXCAN_TX_BUF_ID; i < ARRAY_SIZE(regs->cantxfg); i++) {
888		flexcan_write(FLEXCAN_MB_CODE_RX_INACTIVE,
889			      &regs->cantxfg[i].can_ctrl);
890	}
891
892	/* Errata ERR005829: mark first TX mailbox as INACTIVE */
893	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
894		      &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
895
896	/* mark TX mailbox as INACTIVE */
897	flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
898		      &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
899
900	/* acceptance mask/acceptance code (accept everything) */
901	flexcan_write(0x0, &regs->rxgmask);
902	flexcan_write(0x0, &regs->rx14mask);
903	flexcan_write(0x0, &regs->rx15mask);
904
905	if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES)
906		flexcan_write(0x0, &regs->rxfgmask);
907
908	/*
909	 * On Vybrid, disable memory error detection interrupts
910	 * and freeze mode.
911	 * This also works around errata e5295 which generates
912	 * false positive memory errors and put the device in
913	 * freeze mode.
914	 */
915	if (priv->devtype_data->features & FLEXCAN_HAS_MECR_FEATURES) {
916		/*
917		 * Follow the protocol as described in "Detection
918		 * and Correction of Memory Errors" to write to
919		 * MECR register
920		 */
921		reg_crl2 = flexcan_read(&regs->crl2);
922		reg_crl2 |= FLEXCAN_CRL2_ECRWRE;
923		flexcan_write(reg_crl2, &regs->crl2);
924
925		reg_mecr = flexcan_read(&regs->mecr);
926		reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
927		flexcan_write(reg_mecr, &regs->mecr);
928		reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
929				FLEXCAN_MECR_FANCEI_MSK);
930		flexcan_write(reg_mecr, &regs->mecr);
931	}
932
933	err = flexcan_transceiver_enable(priv);
934	if (err)
935		goto out_chip_disable;
936
937	/* synchronize with the can bus */
938	err = flexcan_chip_unfreeze(priv);
939	if (err)
940		goto out_transceiver_disable;
941
942	priv->can.state = CAN_STATE_ERROR_ACTIVE;
943
944	/* enable FIFO interrupts */
945	flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
946
947	/* print chip status */
948	netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
949		   flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
950
951	return 0;
952
953 out_transceiver_disable:
954	flexcan_transceiver_disable(priv);
955 out_chip_disable:
956	flexcan_chip_disable(priv);
957	return err;
958}
959
960/*
961 * flexcan_chip_stop
962 *
963 * this functions is entered with clocks enabled
964 *
965 */
966static void flexcan_chip_stop(struct net_device *dev)
967{
968	struct flexcan_priv *priv = netdev_priv(dev);
969	struct flexcan_regs __iomem *regs = priv->base;
970
971	/* freeze + disable module */
972	flexcan_chip_freeze(priv);
973	flexcan_chip_disable(priv);
974
975	/* Disable all interrupts */
976	flexcan_write(0, &regs->imask1);
977	flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
978		      &regs->ctrl);
979
980	flexcan_transceiver_disable(priv);
981	priv->can.state = CAN_STATE_STOPPED;
982
983	return;
984}
985
986static int flexcan_open(struct net_device *dev)
987{
988	struct flexcan_priv *priv = netdev_priv(dev);
989	int err;
990
991	err = clk_prepare_enable(priv->clk_ipg);
992	if (err)
993		return err;
994
995	err = clk_prepare_enable(priv->clk_per);
996	if (err)
997		goto out_disable_ipg;
998
999	err = open_candev(dev);
1000	if (err)
1001		goto out_disable_per;
1002
1003	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
1004	if (err)
1005		goto out_close;
1006
1007	/* start chip and queuing */
1008	err = flexcan_chip_start(dev);
1009	if (err)
1010		goto out_free_irq;
1011
1012	can_led_event(dev, CAN_LED_EVENT_OPEN);
1013
1014	napi_enable(&priv->napi);
1015	netif_start_queue(dev);
1016
1017	return 0;
1018
1019 out_free_irq:
1020	free_irq(dev->irq, dev);
1021 out_close:
1022	close_candev(dev);
1023 out_disable_per:
1024	clk_disable_unprepare(priv->clk_per);
1025 out_disable_ipg:
1026	clk_disable_unprepare(priv->clk_ipg);
1027
1028	return err;
1029}
1030
1031static int flexcan_close(struct net_device *dev)
1032{
1033	struct flexcan_priv *priv = netdev_priv(dev);
1034
1035	netif_stop_queue(dev);
1036	napi_disable(&priv->napi);
1037	flexcan_chip_stop(dev);
1038
1039	free_irq(dev->irq, dev);
1040	clk_disable_unprepare(priv->clk_per);
1041	clk_disable_unprepare(priv->clk_ipg);
1042
1043	close_candev(dev);
1044
1045	can_led_event(dev, CAN_LED_EVENT_STOP);
1046
1047	return 0;
1048}
1049
1050static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
1051{
1052	int err;
1053
1054	switch (mode) {
1055	case CAN_MODE_START:
1056		err = flexcan_chip_start(dev);
1057		if (err)
1058			return err;
1059
1060		netif_wake_queue(dev);
1061		break;
1062
1063	default:
1064		return -EOPNOTSUPP;
1065	}
1066
1067	return 0;
1068}
1069
1070static const struct net_device_ops flexcan_netdev_ops = {
1071	.ndo_open	= flexcan_open,
1072	.ndo_stop	= flexcan_close,
1073	.ndo_start_xmit	= flexcan_start_xmit,
1074	.ndo_change_mtu = can_change_mtu,
1075};
1076
1077static int register_flexcandev(struct net_device *dev)
1078{
1079	struct flexcan_priv *priv = netdev_priv(dev);
1080	struct flexcan_regs __iomem *regs = priv->base;
1081	u32 reg, err;
1082
1083	err = clk_prepare_enable(priv->clk_ipg);
1084	if (err)
1085		return err;
1086
1087	err = clk_prepare_enable(priv->clk_per);
1088	if (err)
1089		goto out_disable_ipg;
1090
1091	/* select "bus clock", chip must be disabled */
1092	err = flexcan_chip_disable(priv);
1093	if (err)
1094		goto out_disable_per;
1095	reg = flexcan_read(&regs->ctrl);
1096	reg |= FLEXCAN_CTRL_CLK_SRC;
1097	flexcan_write(reg, &regs->ctrl);
1098
1099	err = flexcan_chip_enable(priv);
1100	if (err)
1101		goto out_chip_disable;
1102
1103	/* set freeze, halt and activate FIFO, restrict register access */
1104	reg = flexcan_read(&regs->mcr);
1105	reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT |
1106		FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1107	flexcan_write(reg, &regs->mcr);
1108
1109	/*
1110	 * Currently we only support newer versions of this core
1111	 * featuring a RX FIFO. Older cores found on some Coldfire
1112	 * derivates are not yet supported.
1113	 */
1114	reg = flexcan_read(&regs->mcr);
1115	if (!(reg & FLEXCAN_MCR_FEN)) {
1116		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1117		err = -ENODEV;
1118		goto out_chip_disable;
1119	}
1120
1121	err = register_candev(dev);
1122
1123	/* disable core and turn off clocks */
1124 out_chip_disable:
1125	flexcan_chip_disable(priv);
1126 out_disable_per:
1127	clk_disable_unprepare(priv->clk_per);
1128 out_disable_ipg:
1129	clk_disable_unprepare(priv->clk_ipg);
1130
1131	return err;
1132}
1133
1134static void unregister_flexcandev(struct net_device *dev)
1135{
1136	unregister_candev(dev);
1137}
1138
1139static const struct of_device_id flexcan_of_match[] = {
1140	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
1141	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
1142	{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
1143	{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
1144	{ /* sentinel */ },
1145};
1146MODULE_DEVICE_TABLE(of, flexcan_of_match);
1147
1148static const struct platform_device_id flexcan_id_table[] = {
1149	{ .name = "flexcan", .driver_data = (kernel_ulong_t)&fsl_p1010_devtype_data, },
1150	{ /* sentinel */ },
1151};
1152MODULE_DEVICE_TABLE(platform, flexcan_id_table);
1153
1154static int flexcan_probe(struct platform_device *pdev)
1155{
1156	const struct of_device_id *of_id;
1157	const struct flexcan_devtype_data *devtype_data;
1158	struct net_device *dev;
1159	struct flexcan_priv *priv;
1160	struct regulator *reg_xceiver;
1161	struct resource *mem;
1162	struct clk *clk_ipg = NULL, *clk_per = NULL;
1163	void __iomem *base;
1164	int err, irq;
1165	u32 clock_freq = 0;
1166
1167	reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
1168	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
1169		return -EPROBE_DEFER;
1170	else if (IS_ERR(reg_xceiver))
1171		reg_xceiver = NULL;
1172
1173	if (pdev->dev.of_node)
1174		of_property_read_u32(pdev->dev.of_node,
1175						"clock-frequency", &clock_freq);
1176
1177	if (!clock_freq) {
1178		clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1179		if (IS_ERR(clk_ipg)) {
1180			dev_err(&pdev->dev, "no ipg clock defined\n");
1181			return PTR_ERR(clk_ipg);
1182		}
1183
1184		clk_per = devm_clk_get(&pdev->dev, "per");
1185		if (IS_ERR(clk_per)) {
1186			dev_err(&pdev->dev, "no per clock defined\n");
1187			return PTR_ERR(clk_per);
1188		}
1189		clock_freq = clk_get_rate(clk_per);
1190	}
1191
1192	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1193	irq = platform_get_irq(pdev, 0);
1194	if (irq <= 0)
1195		return -ENODEV;
1196
1197	base = devm_ioremap_resource(&pdev->dev, mem);
1198	if (IS_ERR(base))
1199		return PTR_ERR(base);
1200
1201	of_id = of_match_device(flexcan_of_match, &pdev->dev);
1202	if (of_id) {
1203		devtype_data = of_id->data;
1204	} else if (platform_get_device_id(pdev)->driver_data) {
1205		devtype_data = (struct flexcan_devtype_data *)
1206			platform_get_device_id(pdev)->driver_data;
1207	} else {
1208		return -ENODEV;
1209	}
1210
1211	dev = alloc_candev(sizeof(struct flexcan_priv), 1);
1212	if (!dev)
1213		return -ENOMEM;
1214
1215	dev->netdev_ops = &flexcan_netdev_ops;
1216	dev->irq = irq;
1217	dev->flags |= IFF_ECHO;
1218
1219	priv = netdev_priv(dev);
1220	priv->can.clock.freq = clock_freq;
1221	priv->can.bittiming_const = &flexcan_bittiming_const;
1222	priv->can.do_set_mode = flexcan_set_mode;
1223	priv->can.do_get_berr_counter = flexcan_get_berr_counter;
1224	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1225		CAN_CTRLMODE_LISTENONLY	| CAN_CTRLMODE_3_SAMPLES |
1226		CAN_CTRLMODE_BERR_REPORTING;
1227	priv->base = base;
1228	priv->clk_ipg = clk_ipg;
1229	priv->clk_per = clk_per;
1230	priv->pdata = dev_get_platdata(&pdev->dev);
1231	priv->devtype_data = devtype_data;
1232
1233	priv->reg_xceiver = reg_xceiver;
1234
1235	netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);
1236
1237	platform_set_drvdata(pdev, dev);
1238	SET_NETDEV_DEV(dev, &pdev->dev);
1239
1240	err = register_flexcandev(dev);
1241	if (err) {
1242		dev_err(&pdev->dev, "registering netdev failed\n");
1243		goto failed_register;
1244	}
1245
1246	devm_can_led_init(dev);
1247
1248	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
1249		 priv->base, dev->irq);
1250
1251	return 0;
1252
1253 failed_register:
1254	free_candev(dev);
1255	return err;
1256}
1257
1258static int flexcan_remove(struct platform_device *pdev)
1259{
1260	struct net_device *dev = platform_get_drvdata(pdev);
1261	struct flexcan_priv *priv = netdev_priv(dev);
1262
1263	unregister_flexcandev(dev);
1264	netif_napi_del(&priv->napi);
1265	free_candev(dev);
1266
1267	return 0;
1268}
1269
1270static int __maybe_unused flexcan_suspend(struct device *device)
1271{
1272	struct net_device *dev = dev_get_drvdata(device);
1273	struct flexcan_priv *priv = netdev_priv(dev);
1274	int err;
1275
1276	err = flexcan_chip_disable(priv);
1277	if (err)
1278		return err;
1279
1280	if (netif_running(dev)) {
1281		netif_stop_queue(dev);
1282		netif_device_detach(dev);
1283	}
1284	priv->can.state = CAN_STATE_SLEEPING;
1285
1286	return 0;
1287}
1288
1289static int __maybe_unused flexcan_resume(struct device *device)
1290{
1291	struct net_device *dev = dev_get_drvdata(device);
1292	struct flexcan_priv *priv = netdev_priv(dev);
1293
1294	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1295	if (netif_running(dev)) {
1296		netif_device_attach(dev);
1297		netif_start_queue(dev);
1298	}
1299	return flexcan_chip_enable(priv);
1300}
1301
1302static SIMPLE_DEV_PM_OPS(flexcan_pm_ops, flexcan_suspend, flexcan_resume);
1303
1304static struct platform_driver flexcan_driver = {
1305	.driver = {
1306		.name = DRV_NAME,
1307		.pm = &flexcan_pm_ops,
1308		.of_match_table = flexcan_of_match,
1309	},
1310	.probe = flexcan_probe,
1311	.remove = flexcan_remove,
1312	.id_table = flexcan_id_table,
1313};
1314
1315module_platform_driver(flexcan_driver);
1316
1317MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
1318	      "Marc Kleine-Budde <kernel@pengutronix.de>");
1319MODULE_LICENSE("GPL v2");
1320MODULE_DESCRIPTION("CAN port driver for flexcan based chip");
1321