1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2008-2010
4  *
5  * - Kurt Van Dijck, EIA Electronics
6  */
7 
8 #include <linux/module.h>
9 #include <linux/interrupt.h>
10 #include <asm/io.h>
11 
12 #include "softing.h"
13 
14 #define TX_ECHO_SKB_MAX (((TXMAX+1)/2)-1)
15 
16 /*
17  * test is a specific CAN netdev
18  * is online (ie. up 'n running, not sleeping, not busoff
19  */
20 static inline int canif_is_active(struct net_device *netdev)
21 {
22 	struct can_priv *can = netdev_priv(netdev);
23 
24 	if (!netif_running(netdev))
25 		return 0;
26 	return (can->state <= CAN_STATE_ERROR_PASSIVE);
27 }
28 
29 /* reset DPRAM */
30 static inline void softing_set_reset_dpram(struct softing *card)
31 {
32 	if (card->pdat->generation >= 2) {
33 		spin_lock_bh(&card->spin);
34 		iowrite8(ioread8(&card->dpram[DPRAM_V2_RESET]) & ~1,
35 				&card->dpram[DPRAM_V2_RESET]);
36 		spin_unlock_bh(&card->spin);
37 	}
38 }
39 
40 static inline void softing_clr_reset_dpram(struct softing *card)
41 {
42 	if (card->pdat->generation >= 2) {
43 		spin_lock_bh(&card->spin);
44 		iowrite8(ioread8(&card->dpram[DPRAM_V2_RESET]) | 1,
45 				&card->dpram[DPRAM_V2_RESET]);
46 		spin_unlock_bh(&card->spin);
47 	}
48 }
49 
50 /* trigger the tx queue-ing */
51 static netdev_tx_t softing_netdev_start_xmit(struct sk_buff *skb,
52 		struct net_device *dev)
53 {
54 	struct softing_priv *priv = netdev_priv(dev);
55 	struct softing *card = priv->card;
56 	int ret;
57 	uint8_t *ptr;
58 	uint8_t fifo_wr, fifo_rd;
59 	struct can_frame *cf = (struct can_frame *)skb->data;
60 	uint8_t buf[DPRAM_TX_SIZE];
61 
62 	if (can_dropped_invalid_skb(dev, skb))
63 		return NETDEV_TX_OK;
64 
65 	spin_lock(&card->spin);
66 
67 	ret = NETDEV_TX_BUSY;
68 	if (!card->fw.up ||
69 			(card->tx.pending >= TXMAX) ||
70 			(priv->tx.pending >= TX_ECHO_SKB_MAX))
71 		goto xmit_done;
72 	fifo_wr = ioread8(&card->dpram[DPRAM_TX_WR]);
73 	fifo_rd = ioread8(&card->dpram[DPRAM_TX_RD]);
74 	if (fifo_wr == fifo_rd)
75 		/* fifo full */
76 		goto xmit_done;
77 	memset(buf, 0, sizeof(buf));
78 	ptr = buf;
79 	*ptr = CMD_TX;
80 	if (cf->can_id & CAN_RTR_FLAG)
81 		*ptr |= CMD_RTR;
82 	if (cf->can_id & CAN_EFF_FLAG)
83 		*ptr |= CMD_XTD;
84 	if (priv->index)
85 		*ptr |= CMD_BUS2;
86 	++ptr;
87 	*ptr++ = cf->len;
88 	*ptr++ = (cf->can_id >> 0);
89 	*ptr++ = (cf->can_id >> 8);
90 	if (cf->can_id & CAN_EFF_FLAG) {
91 		*ptr++ = (cf->can_id >> 16);
92 		*ptr++ = (cf->can_id >> 24);
93 	} else {
94 		/* increment 1, not 2 as you might think */
95 		ptr += 1;
96 	}
97 	if (!(cf->can_id & CAN_RTR_FLAG))
98 		memcpy(ptr, &cf->data[0], cf->len);
99 	memcpy_toio(&card->dpram[DPRAM_TX + DPRAM_TX_SIZE * fifo_wr],
100 			buf, DPRAM_TX_SIZE);
101 	if (++fifo_wr >= DPRAM_TX_CNT)
102 		fifo_wr = 0;
103 	iowrite8(fifo_wr, &card->dpram[DPRAM_TX_WR]);
104 	card->tx.last_bus = priv->index;
105 	++card->tx.pending;
106 	++priv->tx.pending;
107 	can_put_echo_skb(skb, dev, priv->tx.echo_put, 0);
108 	++priv->tx.echo_put;
109 	if (priv->tx.echo_put >= TX_ECHO_SKB_MAX)
110 		priv->tx.echo_put = 0;
111 	/* can_put_echo_skb() saves the skb, safe to return TX_OK */
112 	ret = NETDEV_TX_OK;
113 xmit_done:
114 	spin_unlock(&card->spin);
115 	if (card->tx.pending >= TXMAX) {
116 		int j;
117 		for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
118 			if (card->net[j])
119 				netif_stop_queue(card->net[j]);
120 		}
121 	}
122 	if (ret != NETDEV_TX_OK)
123 		netif_stop_queue(dev);
124 
125 	return ret;
126 }
127 
128 /*
129  * shortcut for skb delivery
130  */
131 int softing_netdev_rx(struct net_device *netdev, const struct can_frame *msg,
132 		ktime_t ktime)
133 {
134 	struct sk_buff *skb;
135 	struct can_frame *cf;
136 
137 	skb = alloc_can_skb(netdev, &cf);
138 	if (!skb)
139 		return -ENOMEM;
140 	memcpy(cf, msg, sizeof(*msg));
141 	skb->tstamp = ktime;
142 	return netif_rx(skb);
143 }
144 
145 /*
146  * softing_handle_1
147  * pop 1 entry from the DPRAM queue, and process
148  */
149 static int softing_handle_1(struct softing *card)
150 {
151 	struct net_device *netdev;
152 	struct softing_priv *priv;
153 	ktime_t ktime;
154 	struct can_frame msg;
155 	int cnt = 0, lost_msg;
156 	uint8_t fifo_rd, fifo_wr, cmd;
157 	uint8_t *ptr;
158 	uint32_t tmp_u32;
159 	uint8_t buf[DPRAM_RX_SIZE];
160 
161 	memset(&msg, 0, sizeof(msg));
162 	/* test for lost msgs */
163 	lost_msg = ioread8(&card->dpram[DPRAM_RX_LOST]);
164 	if (lost_msg) {
165 		int j;
166 		/* reset condition */
167 		iowrite8(0, &card->dpram[DPRAM_RX_LOST]);
168 		/* prepare msg */
169 		msg.can_id = CAN_ERR_FLAG | CAN_ERR_CRTL;
170 		msg.len = CAN_ERR_DLC;
171 		msg.data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
172 		/*
173 		 * service to all buses, we don't know which it was applicable
174 		 * but only service buses that are online
175 		 */
176 		for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
177 			netdev = card->net[j];
178 			if (!netdev)
179 				continue;
180 			if (!canif_is_active(netdev))
181 				/* a dead bus has no overflows */
182 				continue;
183 			++netdev->stats.rx_over_errors;
184 			softing_netdev_rx(netdev, &msg, 0);
185 		}
186 		/* prepare for other use */
187 		memset(&msg, 0, sizeof(msg));
188 		++cnt;
189 	}
190 
191 	fifo_rd = ioread8(&card->dpram[DPRAM_RX_RD]);
192 	fifo_wr = ioread8(&card->dpram[DPRAM_RX_WR]);
193 
194 	if (++fifo_rd >= DPRAM_RX_CNT)
195 		fifo_rd = 0;
196 	if (fifo_wr == fifo_rd)
197 		return cnt;
198 
199 	memcpy_fromio(buf, &card->dpram[DPRAM_RX + DPRAM_RX_SIZE*fifo_rd],
200 			DPRAM_RX_SIZE);
201 	mb();
202 	/* trigger dual port RAM */
203 	iowrite8(fifo_rd, &card->dpram[DPRAM_RX_RD]);
204 
205 	ptr = buf;
206 	cmd = *ptr++;
207 	if (cmd == 0xff)
208 		/* not quite useful, probably the card has got out */
209 		return 0;
210 	netdev = card->net[0];
211 	if (cmd & CMD_BUS2)
212 		netdev = card->net[1];
213 	priv = netdev_priv(netdev);
214 
215 	if (cmd & CMD_ERR) {
216 		uint8_t can_state, state;
217 
218 		state = *ptr++;
219 
220 		msg.can_id = CAN_ERR_FLAG;
221 		msg.len = CAN_ERR_DLC;
222 
223 		if (state & SF_MASK_BUSOFF) {
224 			can_state = CAN_STATE_BUS_OFF;
225 			msg.can_id |= CAN_ERR_BUSOFF;
226 			state = STATE_BUSOFF;
227 		} else if (state & SF_MASK_EPASSIVE) {
228 			can_state = CAN_STATE_ERROR_PASSIVE;
229 			msg.can_id |= CAN_ERR_CRTL;
230 			msg.data[1] = CAN_ERR_CRTL_TX_PASSIVE;
231 			state = STATE_EPASSIVE;
232 		} else {
233 			can_state = CAN_STATE_ERROR_ACTIVE;
234 			msg.can_id |= CAN_ERR_CRTL;
235 			state = STATE_EACTIVE;
236 		}
237 		/* update DPRAM */
238 		iowrite8(state, &card->dpram[priv->index ?
239 				DPRAM_INFO_BUSSTATE2 : DPRAM_INFO_BUSSTATE]);
240 		/* timestamp */
241 		tmp_u32 = le32_to_cpup((void *)ptr);
242 		ktime = softing_raw2ktime(card, tmp_u32);
243 
244 		++netdev->stats.rx_errors;
245 		/* update internal status */
246 		if (can_state != priv->can.state) {
247 			priv->can.state = can_state;
248 			if (can_state == CAN_STATE_ERROR_PASSIVE)
249 				++priv->can.can_stats.error_passive;
250 			else if (can_state == CAN_STATE_BUS_OFF) {
251 				/* this calls can_close_cleanup() */
252 				++priv->can.can_stats.bus_off;
253 				can_bus_off(netdev);
254 				netif_stop_queue(netdev);
255 			}
256 			/* trigger socketcan */
257 			softing_netdev_rx(netdev, &msg, ktime);
258 		}
259 
260 	} else {
261 		if (cmd & CMD_RTR)
262 			msg.can_id |= CAN_RTR_FLAG;
263 		msg.len = can_cc_dlc2len(*ptr++);
264 		if (cmd & CMD_XTD) {
265 			msg.can_id |= CAN_EFF_FLAG;
266 			msg.can_id |= le32_to_cpup((void *)ptr);
267 			ptr += 4;
268 		} else {
269 			msg.can_id |= le16_to_cpup((void *)ptr);
270 			ptr += 2;
271 		}
272 		/* timestamp */
273 		tmp_u32 = le32_to_cpup((void *)ptr);
274 		ptr += 4;
275 		ktime = softing_raw2ktime(card, tmp_u32);
276 		if (!(msg.can_id & CAN_RTR_FLAG))
277 			memcpy(&msg.data[0], ptr, 8);
278 		/* update socket */
279 		if (cmd & CMD_ACK) {
280 			/* acknowledge, was tx msg */
281 			struct sk_buff *skb;
282 			skb = priv->can.echo_skb[priv->tx.echo_get];
283 			if (skb)
284 				skb->tstamp = ktime;
285 			can_get_echo_skb(netdev, priv->tx.echo_get, NULL);
286 			++priv->tx.echo_get;
287 			if (priv->tx.echo_get >= TX_ECHO_SKB_MAX)
288 				priv->tx.echo_get = 0;
289 			if (priv->tx.pending)
290 				--priv->tx.pending;
291 			if (card->tx.pending)
292 				--card->tx.pending;
293 			++netdev->stats.tx_packets;
294 			if (!(msg.can_id & CAN_RTR_FLAG))
295 				netdev->stats.tx_bytes += msg.len;
296 		} else {
297 			int ret;
298 
299 			ret = softing_netdev_rx(netdev, &msg, ktime);
300 			if (ret == NET_RX_SUCCESS) {
301 				++netdev->stats.rx_packets;
302 				if (!(msg.can_id & CAN_RTR_FLAG))
303 					netdev->stats.rx_bytes += msg.len;
304 			} else {
305 				++netdev->stats.rx_dropped;
306 			}
307 		}
308 	}
309 	++cnt;
310 	return cnt;
311 }
312 
313 /*
314  * real interrupt handler
315  */
316 static irqreturn_t softing_irq_thread(int irq, void *dev_id)
317 {
318 	struct softing *card = (struct softing *)dev_id;
319 	struct net_device *netdev;
320 	struct softing_priv *priv;
321 	int j, offset, work_done;
322 
323 	work_done = 0;
324 	spin_lock_bh(&card->spin);
325 	while (softing_handle_1(card) > 0) {
326 		++card->irq.svc_count;
327 		++work_done;
328 	}
329 	spin_unlock_bh(&card->spin);
330 	/* resume tx queue's */
331 	offset = card->tx.last_bus;
332 	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
333 		if (card->tx.pending >= TXMAX)
334 			break;
335 		netdev = card->net[(j + offset + 1) % card->pdat->nbus];
336 		if (!netdev)
337 			continue;
338 		priv = netdev_priv(netdev);
339 		if (!canif_is_active(netdev))
340 			/* it makes no sense to wake dead buses */
341 			continue;
342 		if (priv->tx.pending >= TX_ECHO_SKB_MAX)
343 			continue;
344 		++work_done;
345 		netif_wake_queue(netdev);
346 	}
347 	return work_done ? IRQ_HANDLED : IRQ_NONE;
348 }
349 
350 /*
351  * interrupt routines:
352  * schedule the 'real interrupt handler'
353  */
354 static irqreturn_t softing_irq_v2(int irq, void *dev_id)
355 {
356 	struct softing *card = (struct softing *)dev_id;
357 	uint8_t ir;
358 
359 	ir = ioread8(&card->dpram[DPRAM_V2_IRQ_TOHOST]);
360 	iowrite8(0, &card->dpram[DPRAM_V2_IRQ_TOHOST]);
361 	return (1 == ir) ? IRQ_WAKE_THREAD : IRQ_NONE;
362 }
363 
364 static irqreturn_t softing_irq_v1(int irq, void *dev_id)
365 {
366 	struct softing *card = (struct softing *)dev_id;
367 	uint8_t ir;
368 
369 	ir = ioread8(&card->dpram[DPRAM_IRQ_TOHOST]);
370 	iowrite8(0, &card->dpram[DPRAM_IRQ_TOHOST]);
371 	return ir ? IRQ_WAKE_THREAD : IRQ_NONE;
372 }
373 
374 /*
375  * netdev/candev interoperability
376  */
377 static int softing_netdev_open(struct net_device *ndev)
378 {
379 	int ret;
380 
381 	/* check or determine and set bittime */
382 	ret = open_candev(ndev);
383 	if (ret)
384 		return ret;
385 
386 	ret = softing_startstop(ndev, 1);
387 	if (ret < 0)
388 		close_candev(ndev);
389 
390 	return ret;
391 }
392 
393 static int softing_netdev_stop(struct net_device *ndev)
394 {
395 	int ret;
396 
397 	netif_stop_queue(ndev);
398 
399 	/* softing cycle does close_candev() */
400 	ret = softing_startstop(ndev, 0);
401 	return ret;
402 }
403 
404 static int softing_candev_set_mode(struct net_device *ndev, enum can_mode mode)
405 {
406 	int ret;
407 
408 	switch (mode) {
409 	case CAN_MODE_START:
410 		/* softing_startstop does close_candev() */
411 		ret = softing_startstop(ndev, 1);
412 		return ret;
413 	case CAN_MODE_STOP:
414 	case CAN_MODE_SLEEP:
415 		return -EOPNOTSUPP;
416 	}
417 	return 0;
418 }
419 
420 /*
421  * Softing device management helpers
422  */
423 int softing_enable_irq(struct softing *card, int enable)
424 {
425 	int ret;
426 
427 	if (!card->irq.nr) {
428 		return 0;
429 	} else if (card->irq.requested && !enable) {
430 		free_irq(card->irq.nr, card);
431 		card->irq.requested = 0;
432 	} else if (!card->irq.requested && enable) {
433 		ret = request_threaded_irq(card->irq.nr,
434 				(card->pdat->generation >= 2) ?
435 					softing_irq_v2 : softing_irq_v1,
436 				softing_irq_thread, IRQF_SHARED,
437 				dev_name(&card->pdev->dev), card);
438 		if (ret) {
439 			dev_alert(&card->pdev->dev,
440 					"request_threaded_irq(%u) failed\n",
441 					card->irq.nr);
442 			return ret;
443 		}
444 		card->irq.requested = 1;
445 	}
446 	return 0;
447 }
448 
449 static void softing_card_shutdown(struct softing *card)
450 {
451 	int fw_up = 0;
452 
453 	if (mutex_lock_interruptible(&card->fw.lock)) {
454 		/* return -ERESTARTSYS */;
455 	}
456 	fw_up = card->fw.up;
457 	card->fw.up = 0;
458 
459 	if (card->irq.requested && card->irq.nr) {
460 		free_irq(card->irq.nr, card);
461 		card->irq.requested = 0;
462 	}
463 	if (fw_up) {
464 		if (card->pdat->enable_irq)
465 			card->pdat->enable_irq(card->pdev, 0);
466 		softing_set_reset_dpram(card);
467 		if (card->pdat->reset)
468 			card->pdat->reset(card->pdev, 1);
469 	}
470 	mutex_unlock(&card->fw.lock);
471 }
472 
473 static int softing_card_boot(struct softing *card)
474 {
475 	int ret, j;
476 	static const uint8_t stream[] = {
477 		0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, };
478 	unsigned char back[sizeof(stream)];
479 
480 	if (mutex_lock_interruptible(&card->fw.lock))
481 		return -ERESTARTSYS;
482 	if (card->fw.up) {
483 		mutex_unlock(&card->fw.lock);
484 		return 0;
485 	}
486 	/* reset board */
487 	if (card->pdat->enable_irq)
488 		card->pdat->enable_irq(card->pdev, 1);
489 	/* boot card */
490 	softing_set_reset_dpram(card);
491 	if (card->pdat->reset)
492 		card->pdat->reset(card->pdev, 1);
493 	for (j = 0; (j + sizeof(stream)) < card->dpram_size;
494 			j += sizeof(stream)) {
495 
496 		memcpy_toio(&card->dpram[j], stream, sizeof(stream));
497 		/* flush IO cache */
498 		mb();
499 		memcpy_fromio(back, &card->dpram[j], sizeof(stream));
500 
501 		if (!memcmp(back, stream, sizeof(stream)))
502 			continue;
503 		/* memory is not equal */
504 		dev_alert(&card->pdev->dev, "dpram failed at 0x%04x\n", j);
505 		ret = -EIO;
506 		goto failed;
507 	}
508 	wmb();
509 	/* load boot firmware */
510 	ret = softing_load_fw(card->pdat->boot.fw, card, card->dpram,
511 				card->dpram_size,
512 				card->pdat->boot.offs - card->pdat->boot.addr);
513 	if (ret < 0)
514 		goto failed;
515 	/* load loader firmware */
516 	ret = softing_load_fw(card->pdat->load.fw, card, card->dpram,
517 				card->dpram_size,
518 				card->pdat->load.offs - card->pdat->load.addr);
519 	if (ret < 0)
520 		goto failed;
521 
522 	if (card->pdat->reset)
523 		card->pdat->reset(card->pdev, 0);
524 	softing_clr_reset_dpram(card);
525 	ret = softing_bootloader_command(card, 0, "card boot");
526 	if (ret < 0)
527 		goto failed;
528 	ret = softing_load_app_fw(card->pdat->app.fw, card);
529 	if (ret < 0)
530 		goto failed;
531 
532 	ret = softing_chip_poweron(card);
533 	if (ret < 0)
534 		goto failed;
535 
536 	card->fw.up = 1;
537 	mutex_unlock(&card->fw.lock);
538 	return 0;
539 failed:
540 	card->fw.up = 0;
541 	if (card->pdat->enable_irq)
542 		card->pdat->enable_irq(card->pdev, 0);
543 	softing_set_reset_dpram(card);
544 	if (card->pdat->reset)
545 		card->pdat->reset(card->pdev, 1);
546 	mutex_unlock(&card->fw.lock);
547 	return ret;
548 }
549 
550 /*
551  * netdev sysfs
552  */
553 static ssize_t show_chip(struct device *dev, struct device_attribute *attr,
554 		char *buf)
555 {
556 	struct net_device *ndev = to_net_dev(dev);
557 	struct softing_priv *priv = netdev2softing(ndev);
558 
559 	return sprintf(buf, "%i\n", priv->chip);
560 }
561 
562 static ssize_t show_output(struct device *dev, struct device_attribute *attr,
563 		char *buf)
564 {
565 	struct net_device *ndev = to_net_dev(dev);
566 	struct softing_priv *priv = netdev2softing(ndev);
567 
568 	return sprintf(buf, "0x%02x\n", priv->output);
569 }
570 
571 static ssize_t store_output(struct device *dev, struct device_attribute *attr,
572 		const char *buf, size_t count)
573 {
574 	struct net_device *ndev = to_net_dev(dev);
575 	struct softing_priv *priv = netdev2softing(ndev);
576 	struct softing *card = priv->card;
577 	unsigned long val;
578 	int ret;
579 
580 	ret = kstrtoul(buf, 0, &val);
581 	if (ret < 0)
582 		return ret;
583 	val &= 0xFF;
584 
585 	ret = mutex_lock_interruptible(&card->fw.lock);
586 	if (ret)
587 		return -ERESTARTSYS;
588 	if (netif_running(ndev)) {
589 		mutex_unlock(&card->fw.lock);
590 		return -EBUSY;
591 	}
592 	priv->output = val;
593 	mutex_unlock(&card->fw.lock);
594 	return count;
595 }
596 
597 static const DEVICE_ATTR(chip, 0444, show_chip, NULL);
598 static const DEVICE_ATTR(output, 0644, show_output, store_output);
599 
600 static const struct attribute *const netdev_sysfs_attrs[] = {
601 	&dev_attr_chip.attr,
602 	&dev_attr_output.attr,
603 	NULL,
604 };
605 static const struct attribute_group netdev_sysfs_group = {
606 	.name = NULL,
607 	.attrs = (struct attribute **)netdev_sysfs_attrs,
608 };
609 
610 static const struct net_device_ops softing_netdev_ops = {
611 	.ndo_open = softing_netdev_open,
612 	.ndo_stop = softing_netdev_stop,
613 	.ndo_start_xmit	= softing_netdev_start_xmit,
614 	.ndo_change_mtu = can_change_mtu,
615 };
616 
617 static const struct can_bittiming_const softing_btr_const = {
618 	.name = "softing",
619 	.tseg1_min = 1,
620 	.tseg1_max = 16,
621 	.tseg2_min = 1,
622 	.tseg2_max = 8,
623 	.sjw_max = 4, /* overruled */
624 	.brp_min = 1,
625 	.brp_max = 32, /* overruled */
626 	.brp_inc = 1,
627 };
628 
629 
630 static struct net_device *softing_netdev_create(struct softing *card,
631 						uint16_t chip_id)
632 {
633 	struct net_device *netdev;
634 	struct softing_priv *priv;
635 
636 	netdev = alloc_candev(sizeof(*priv), TX_ECHO_SKB_MAX);
637 	if (!netdev) {
638 		dev_alert(&card->pdev->dev, "alloc_candev failed\n");
639 		return NULL;
640 	}
641 	priv = netdev_priv(netdev);
642 	priv->netdev = netdev;
643 	priv->card = card;
644 	memcpy(&priv->btr_const, &softing_btr_const, sizeof(priv->btr_const));
645 	priv->btr_const.brp_max = card->pdat->max_brp;
646 	priv->btr_const.sjw_max = card->pdat->max_sjw;
647 	priv->can.bittiming_const = &priv->btr_const;
648 	priv->can.clock.freq = 8000000;
649 	priv->chip = chip_id;
650 	priv->output = softing_default_output(netdev);
651 	SET_NETDEV_DEV(netdev, &card->pdev->dev);
652 
653 	netdev->flags |= IFF_ECHO;
654 	netdev->netdev_ops = &softing_netdev_ops;
655 	priv->can.do_set_mode = softing_candev_set_mode;
656 	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
657 
658 	return netdev;
659 }
660 
661 static int softing_netdev_register(struct net_device *netdev)
662 {
663 	int ret;
664 
665 	ret = register_candev(netdev);
666 	if (ret) {
667 		dev_alert(&netdev->dev, "register failed\n");
668 		return ret;
669 	}
670 	if (sysfs_create_group(&netdev->dev.kobj, &netdev_sysfs_group) < 0)
671 		netdev_alert(netdev, "sysfs group failed\n");
672 
673 	return 0;
674 }
675 
676 static void softing_netdev_cleanup(struct net_device *netdev)
677 {
678 	sysfs_remove_group(&netdev->dev.kobj, &netdev_sysfs_group);
679 	unregister_candev(netdev);
680 	free_candev(netdev);
681 }
682 
683 /*
684  * sysfs for Platform device
685  */
686 #define DEV_ATTR_RO(name, member) \
687 static ssize_t show_##name(struct device *dev, \
688 		struct device_attribute *attr, char *buf) \
689 { \
690 	struct softing *card = dev_get_drvdata(dev); \
691 	return sprintf(buf, "%u\n", card->member); \
692 } \
693 static DEVICE_ATTR(name, 0444, show_##name, NULL)
694 
695 #define DEV_ATTR_RO_STR(name, member) \
696 static ssize_t show_##name(struct device *dev, \
697 		struct device_attribute *attr, char *buf) \
698 { \
699 	struct softing *card = dev_get_drvdata(dev); \
700 	return sprintf(buf, "%s\n", card->member); \
701 } \
702 static DEVICE_ATTR(name, 0444, show_##name, NULL)
703 
704 DEV_ATTR_RO(serial, id.serial);
705 DEV_ATTR_RO_STR(firmware, pdat->app.fw);
706 DEV_ATTR_RO(firmware_version, id.fw_version);
707 DEV_ATTR_RO_STR(hardware, pdat->name);
708 DEV_ATTR_RO(hardware_version, id.hw_version);
709 DEV_ATTR_RO(license, id.license);
710 
711 static struct attribute *softing_pdev_attrs[] = {
712 	&dev_attr_serial.attr,
713 	&dev_attr_firmware.attr,
714 	&dev_attr_firmware_version.attr,
715 	&dev_attr_hardware.attr,
716 	&dev_attr_hardware_version.attr,
717 	&dev_attr_license.attr,
718 	NULL,
719 };
720 
721 static const struct attribute_group softing_pdev_group = {
722 	.name = NULL,
723 	.attrs = softing_pdev_attrs,
724 };
725 
726 /*
727  * platform driver
728  */
729 static int softing_pdev_remove(struct platform_device *pdev)
730 {
731 	struct softing *card = platform_get_drvdata(pdev);
732 	int j;
733 
734 	/* first, disable card*/
735 	softing_card_shutdown(card);
736 
737 	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
738 		if (!card->net[j])
739 			continue;
740 		softing_netdev_cleanup(card->net[j]);
741 		card->net[j] = NULL;
742 	}
743 	sysfs_remove_group(&pdev->dev.kobj, &softing_pdev_group);
744 
745 	iounmap(card->dpram);
746 	kfree(card);
747 	return 0;
748 }
749 
750 static int softing_pdev_probe(struct platform_device *pdev)
751 {
752 	const struct softing_platform_data *pdat = dev_get_platdata(&pdev->dev);
753 	struct softing *card;
754 	struct net_device *netdev;
755 	struct softing_priv *priv;
756 	struct resource *pres;
757 	int ret;
758 	int j;
759 
760 	if (!pdat) {
761 		dev_warn(&pdev->dev, "no platform data\n");
762 		return -EINVAL;
763 	}
764 	if (pdat->nbus > ARRAY_SIZE(card->net)) {
765 		dev_warn(&pdev->dev, "%u nets??\n", pdat->nbus);
766 		return -EINVAL;
767 	}
768 
769 	card = kzalloc(sizeof(*card), GFP_KERNEL);
770 	if (!card)
771 		return -ENOMEM;
772 	card->pdat = pdat;
773 	card->pdev = pdev;
774 	platform_set_drvdata(pdev, card);
775 	mutex_init(&card->fw.lock);
776 	spin_lock_init(&card->spin);
777 
778 	ret = -EINVAL;
779 	pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
780 	if (!pres)
781 		goto platform_resource_failed;
782 	card->dpram_phys = pres->start;
783 	card->dpram_size = resource_size(pres);
784 	card->dpram = ioremap(card->dpram_phys, card->dpram_size);
785 	if (!card->dpram) {
786 		dev_alert(&card->pdev->dev, "dpram ioremap failed\n");
787 		goto ioremap_failed;
788 	}
789 
790 	pres = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
791 	if (pres)
792 		card->irq.nr = pres->start;
793 
794 	/* reset card */
795 	ret = softing_card_boot(card);
796 	if (ret < 0) {
797 		dev_alert(&pdev->dev, "failed to boot\n");
798 		goto boot_failed;
799 	}
800 
801 	/* only now, the chip's are known */
802 	card->id.freq = card->pdat->freq;
803 
804 	ret = sysfs_create_group(&pdev->dev.kobj, &softing_pdev_group);
805 	if (ret < 0) {
806 		dev_alert(&card->pdev->dev, "sysfs failed\n");
807 		goto sysfs_failed;
808 	}
809 
810 	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
811 		card->net[j] = netdev =
812 			softing_netdev_create(card, card->id.chip[j]);
813 		if (!netdev) {
814 			dev_alert(&pdev->dev, "failed to make can[%i]", j);
815 			ret = -ENOMEM;
816 			goto netdev_failed;
817 		}
818 		netdev->dev_id = j;
819 		priv = netdev_priv(card->net[j]);
820 		priv->index = j;
821 		ret = softing_netdev_register(netdev);
822 		if (ret) {
823 			free_candev(netdev);
824 			card->net[j] = NULL;
825 			dev_alert(&card->pdev->dev,
826 					"failed to register can[%i]\n", j);
827 			goto netdev_failed;
828 		}
829 	}
830 	dev_info(&card->pdev->dev, "%s ready.\n", card->pdat->name);
831 	return 0;
832 
833 netdev_failed:
834 	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
835 		if (!card->net[j])
836 			continue;
837 		softing_netdev_cleanup(card->net[j]);
838 	}
839 	sysfs_remove_group(&pdev->dev.kobj, &softing_pdev_group);
840 sysfs_failed:
841 	softing_card_shutdown(card);
842 boot_failed:
843 	iounmap(card->dpram);
844 ioremap_failed:
845 platform_resource_failed:
846 	kfree(card);
847 	return ret;
848 }
849 
850 static struct platform_driver softing_driver = {
851 	.driver = {
852 		.name = "softing",
853 	},
854 	.probe = softing_pdev_probe,
855 	.remove = softing_pdev_remove,
856 };
857 
858 module_platform_driver(softing_driver);
859 
860 MODULE_ALIAS("platform:softing");
861 MODULE_DESCRIPTION("Softing DPRAM CAN driver");
862 MODULE_AUTHOR("Kurt Van Dijck <kurt.van.dijck@eia.be>");
863 MODULE_LICENSE("GPL v2");
864