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