2 * CAN bus driver for the alone generic (as possible as) MSCAN controller.
4 * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>,
6 * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
7 * Copytight (C) 2008-2009 Pengutronix <kernel@pengutronix.de>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the version 2 of the GNU General Public License
11 * as published by the Free Software Foundation
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/interrupt.h>
26 #include <linux/delay.h>
27 #include <linux/netdevice.h>
28 #include <linux/if_arp.h>
29 #include <linux/if_ether.h>
30 #include <linux/list.h>
31 #include <socketcan/can.h>
32 #include <socketcan/can/dev.h>
33 #include <socketcan/can/error.h>
34 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
42 #include <socketcan/can/version.h> /* for RCSID. Removed by mkpatch script */
45 static struct can_bittiming_const mscan_bittiming_const = {
63 static enum can_state state_map[] = {
64 CAN_STATE_ERROR_ACTIVE,
65 CAN_STATE_ERROR_WARNING,
66 CAN_STATE_ERROR_PASSIVE,
70 static int mscan_set_mode(struct net_device *dev, u8 mode)
72 struct mscan_priv *priv = netdev_priv(dev);
73 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
78 if (mode != MSCAN_NORMAL_MODE) {
79 if (priv->tx_active) {
80 /* Abort transfers before going to sleep */#
81 out_8(®s->cantarq, priv->tx_active);
82 /* Suppress TX done interrupts */
83 out_8(®s->cantier, 0);
86 canctl1 = in_8(®s->canctl1);
87 if ((mode & MSCAN_SLPRQ) && !(canctl1 & MSCAN_SLPAK)) {
88 setbits8(®s->canctl0, MSCAN_SLPRQ);
89 for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
90 if (in_8(®s->canctl1) & MSCAN_SLPAK)
95 * The mscan controller will fail to enter sleep mode,
96 * while there are irregular activities on bus, like
97 * somebody keeps retransmitting. This behavior is
98 * undocumented and seems to differ between mscan built
99 * in mpc5200b and mpc5200. We proceed in that case,
100 * since otherwise the slprq will be kept set and the
101 * controller will get stuck. NOTE: INITRQ or CSWAI
102 * will abort all active transmit actions, if still
105 if (i >= MSCAN_SET_MODE_RETRIES)
107 "device failed to enter sleep mode. "
108 "We proceed anyhow.\n");
110 priv->can.state = CAN_STATE_SLEEPING;
113 if ((mode & MSCAN_INITRQ) && !(canctl1 & MSCAN_INITAK)) {
114 setbits8(®s->canctl0, MSCAN_INITRQ);
115 for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
116 if (in_8(®s->canctl1) & MSCAN_INITAK)
119 if (i >= MSCAN_SET_MODE_RETRIES)
123 priv->can.state = CAN_STATE_STOPPED;
125 if (mode & MSCAN_CSWAI)
126 setbits8(®s->canctl0, MSCAN_CSWAI);
129 canctl1 = in_8(®s->canctl1);
130 if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) {
131 clrbits8(®s->canctl0, MSCAN_SLPRQ | MSCAN_INITRQ);
132 for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
133 canctl1 = in_8(®s->canctl1);
134 if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK)))
137 if (i >= MSCAN_SET_MODE_RETRIES)
140 priv->can.state = CAN_STATE_ERROR_ACTIVE;
146 static int mscan_start(struct net_device *dev)
148 struct mscan_priv *priv = netdev_priv(dev);
149 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
153 out_8(®s->canrier, 0);
155 INIT_LIST_HEAD(&priv->tx_head);
156 priv->prev_buf_id = 0;
159 priv->shadow_canrier = 0;
162 err = mscan_set_mode(dev, MSCAN_NORMAL_MODE);
166 canrflg = in_8(®s->canrflg);
167 priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
168 priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg),
169 MSCAN_STATE_TX(canrflg))];
170 out_8(®s->cantier, 0);
172 /* Enable receive interrupts. */
173 out_8(®s->canrier, MSCAN_OVRIE | MSCAN_RXFIE | MSCAN_CSCIE |
174 MSCAN_RSTATE1 | MSCAN_RSTATE0 | MSCAN_TSTATE1 | MSCAN_TSTATE0);
179 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
180 static int mscan_start_xmit(struct sk_buff *skb, struct net_device *dev)
182 static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev)
185 struct can_frame *frame = (struct can_frame *)skb->data;
186 struct mscan_priv *priv = netdev_priv(dev);
187 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
191 if (frame->can_dlc > 8)
194 out_8(®s->cantier, 0);
196 i = ~priv->tx_active & MSCAN_TXE;
198 switch (hweight8(i)) {
200 netif_stop_queue(dev);
201 dev_err(ND2D(dev), "Tx Ring full when queue awake!\n");
202 return NETDEV_TX_BUSY;
205 * if buf_id < 3, then current frame will be send out of order,
206 * since buffer with lower id have higher priority (hell..)
208 netif_stop_queue(dev);
210 if (buf_id < priv->prev_buf_id) {
212 if (priv->cur_pri == 0xff) {
213 set_bit(F_TX_WAIT_ALL, &priv->flags);
214 netif_stop_queue(dev);
217 set_bit(F_TX_PROGRESS, &priv->flags);
220 priv->prev_buf_id = buf_id;
221 out_8(®s->cantbsel, i);
223 rtr = frame->can_id & CAN_RTR_FLAG;
225 /* RTR is always the lowest bit of interest, then IDs follow */
226 if (frame->can_id & CAN_EFF_FLAG) {
227 can_id = (frame->can_id & CAN_EFF_MASK)
228 << (MSCAN_EFF_RTR_SHIFT + 1);
230 can_id |= 1 << MSCAN_EFF_RTR_SHIFT;
231 out_be16(®s->tx.idr3_2, can_id);
234 /* EFF_FLAGS are inbetween the IDs :( */
235 can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0)
238 can_id = (frame->can_id & CAN_SFF_MASK)
239 << (MSCAN_SFF_RTR_SHIFT + 1);
241 can_id |= 1 << MSCAN_SFF_RTR_SHIFT;
243 out_be16(®s->tx.idr1_0, can_id);
246 void __iomem *data = ®s->tx.dsr1_0;
247 u16 *payload = (u16 *)frame->data;
249 /* It is safe to write into dsr[dlc+1] */
250 for (i = 0; i < (frame->can_dlc + 1) / 2; i++) {
251 out_be16(data, *payload++);
252 data += 2 + _MSCAN_RESERVED_DSR_SIZE;
256 out_8(®s->tx.dlr, frame->can_dlc);
257 out_8(®s->tx.tbpr, priv->cur_pri);
259 /* Start transmission. */
260 out_8(®s->cantflg, 1 << buf_id);
262 if (!test_bit(F_TX_PROGRESS, &priv->flags))
263 dev->trans_start = jiffies;
265 list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head);
267 can_put_echo_skb(skb, dev, buf_id);
269 /* Enable interrupt. */
270 priv->tx_active |= 1 << buf_id;
271 out_8(®s->cantier, priv->tx_active);
276 /* This function returns the old state to see where we came from */
277 static enum can_state check_set_state(struct net_device *dev, u8 canrflg)
279 struct mscan_priv *priv = netdev_priv(dev);
280 enum can_state state, old_state = priv->can.state;
282 if (canrflg & MSCAN_CSCIF && old_state <= CAN_STATE_BUS_OFF) {
283 state = state_map[max(MSCAN_STATE_RX(canrflg),
284 MSCAN_STATE_TX(canrflg))];
285 priv->can.state = state;
290 static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame)
292 struct mscan_priv *priv = netdev_priv(dev);
293 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
297 can_id = in_be16(®s->rx.idr1_0);
298 if (can_id & (1 << 3)) {
299 frame->can_id = CAN_EFF_FLAG;
300 can_id = ((can_id << 16) | in_be16(®s->rx.idr3_2));
301 can_id = ((can_id & 0xffe00000) |
302 ((can_id & 0x7ffff) << 2)) >> 2;
308 frame->can_id |= can_id >> 1;
310 frame->can_id |= CAN_RTR_FLAG;
312 frame->can_dlc = get_can_dlc(in_8(®s->rx.dlr) & 0xf);
314 if (!(frame->can_id & CAN_RTR_FLAG)) {
315 void __iomem *data = ®s->rx.dsr1_0;
316 u16 *payload = (u16 *)frame->data;
318 for (i = 0; i < (frame->can_dlc + 1) / 2; i++) {
319 *payload++ = in_be16(data);
320 data += 2 + _MSCAN_RESERVED_DSR_SIZE;
324 out_8(®s->canrflg, MSCAN_RXF);
327 static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame,
330 struct mscan_priv *priv = netdev_priv(dev);
331 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
332 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
333 struct net_device_stats *stats = can_get_stats(dev);
335 struct net_device_stats *stats = &dev->stats;
337 enum can_state old_state;
339 dev_dbg(ND2D(dev), "error interrupt (canrflg=%#x)\n", canrflg);
340 frame->can_id = CAN_ERR_FLAG;
342 if (canrflg & MSCAN_OVRIF) {
343 frame->can_id |= CAN_ERR_CRTL;
344 frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
345 stats->rx_over_errors++;
351 old_state = check_set_state(dev, canrflg);
353 if (old_state != priv->can.state) {
354 switch (priv->can.state) {
355 case CAN_STATE_ERROR_WARNING:
356 frame->can_id |= CAN_ERR_CRTL;
357 priv->can.can_stats.error_warning++;
358 if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) <
359 (canrflg & MSCAN_RSTAT_MSK))
360 frame->data[1] |= CAN_ERR_CRTL_RX_WARNING;
361 if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) <
362 (canrflg & MSCAN_TSTAT_MSK))
363 frame->data[1] |= CAN_ERR_CRTL_TX_WARNING;
365 case CAN_STATE_ERROR_PASSIVE:
366 frame->can_id |= CAN_ERR_CRTL;
367 priv->can.can_stats.error_passive++;
368 frame->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
370 case CAN_STATE_BUS_OFF:
371 frame->can_id |= CAN_ERR_BUSOFF;
373 * The MSCAN on the MPC5200 does recover from bus-off
374 * automatically. To avoid that we stop the chip doing
375 * a light-weight stop (we are in irq-context).
377 out_8(®s->cantier, 0);
378 out_8(®s->canrier, 0);
379 setbits8(®s->canctl0, MSCAN_SLPRQ | MSCAN_INITRQ);
386 priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
387 frame->can_dlc = CAN_ERR_DLC;
388 out_8(®s->canrflg, MSCAN_ERR_IF);
391 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
392 static int mscan_rx_poll(struct napi_struct *napi, int quota)
394 static int mscan_rx_poll(struct net_device *dev, int *budget)
397 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
398 struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi);
399 struct net_device *dev = napi->dev;
400 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
401 struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi);
402 struct net_device *dev = priv->dev;
404 struct mscan_priv *priv = netdev_priv(dev);
405 int quota = min(dev->quota, *budget);
407 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
408 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
409 struct net_device_stats *stats = can_get_stats(dev);
411 struct net_device_stats *stats = &dev->stats;
416 struct can_frame *frame;
419 while (npackets < quota) {
420 canrflg = in_8(®s->canrflg);
421 if (!(canrflg & (MSCAN_RXF | MSCAN_ERR_IF)))
424 skb = alloc_can_skb(dev, &frame);
426 if (printk_ratelimit())
427 dev_notice(ND2D(dev), "packet dropped\n");
429 out_8(®s->canrflg, canrflg);
433 if (canrflg & MSCAN_RXF)
434 mscan_get_rx_frame(dev, frame);
435 else if (canrflg & MSCAN_ERR_IF)
436 mscan_get_err_frame(dev, frame, canrflg);
438 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
439 dev->last_rx = jiffies;
442 stats->rx_bytes += frame->can_dlc;
444 netif_receive_skb(skb);
447 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
449 dev->quota -= npackets;
452 if (!(in_8(®s->canrflg) & (MSCAN_RXF | MSCAN_ERR_IF))) {
453 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
454 napi_complete(&priv->napi);
455 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
456 netif_rx_complete(dev, &priv->napi);
458 netif_rx_complete(dev);
460 clear_bit(F_RX_PROGRESS, &priv->flags);
461 if (priv->can.state < CAN_STATE_BUS_OFF)
462 out_8(®s->canrier, priv->shadow_canrier);
468 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,19)
469 static irqreturn_t mscan_isr(int irq, void *dev_id, struct pt_regs *r)
471 static irqreturn_t mscan_isr(int irq, void *dev_id)
474 struct net_device *dev = (struct net_device *)dev_id;
475 struct mscan_priv *priv = netdev_priv(dev);
476 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
477 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
478 struct net_device_stats *stats = can_get_stats(dev);
480 struct net_device_stats *stats = &dev->stats;
482 u8 cantier, cantflg, canrflg;
483 irqreturn_t ret = IRQ_NONE;
485 cantier = in_8(®s->cantier) & MSCAN_TXE;
486 cantflg = in_8(®s->cantflg) & cantier;
488 if (cantier && cantflg) {
489 struct list_head *tmp, *pos;
491 list_for_each_safe(pos, tmp, &priv->tx_head) {
492 struct tx_queue_entry *entry =
493 list_entry(pos, struct tx_queue_entry, list);
494 u8 mask = entry->mask;
496 if (!(cantflg & mask))
499 out_8(®s->cantbsel, mask);
500 stats->tx_bytes += in_8(®s->tx.dlr);
502 can_get_echo_skb(dev, entry->id);
503 priv->tx_active &= ~mask;
507 if (list_empty(&priv->tx_head)) {
508 clear_bit(F_TX_WAIT_ALL, &priv->flags);
509 clear_bit(F_TX_PROGRESS, &priv->flags);
512 dev->trans_start = jiffies;
515 if (!test_bit(F_TX_WAIT_ALL, &priv->flags))
516 netif_wake_queue(dev);
518 out_8(®s->cantier, priv->tx_active);
522 canrflg = in_8(®s->canrflg);
523 if ((canrflg & ~MSCAN_STAT_MSK) &&
524 !test_and_set_bit(F_RX_PROGRESS, &priv->flags)) {
525 if (canrflg & ~MSCAN_STAT_MSK) {
526 priv->shadow_canrier = in_8(®s->canrier);
527 out_8(®s->canrier, 0);
528 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
529 napi_schedule(&priv->napi);
530 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
531 netif_rx_schedule(dev, &priv->napi);
533 netif_rx_schedule(dev);
537 clear_bit(F_RX_PROGRESS, &priv->flags);
543 static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode)
545 struct mscan_priv *priv = netdev_priv(dev);
548 if (!priv->open_time)
553 if (priv->can.state <= CAN_STATE_BUS_OFF)
554 mscan_set_mode(dev, MSCAN_INIT_MODE);
555 ret = mscan_start(dev);
558 if (netif_queue_stopped(dev))
559 netif_wake_queue(dev);
569 static int mscan_do_set_bittiming(struct net_device *dev)
571 struct mscan_priv *priv = netdev_priv(dev);
572 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
573 struct can_bittiming *bt = &priv->can.bittiming;
576 btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw);
577 btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) |
578 BTR1_SET_TSEG2(bt->phase_seg2) |
579 BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES));
581 dev_info(ND2D(dev), "setting BTR0=0x%02x BTR1=0x%02x\n",
584 out_8(®s->canbtr0, btr0);
585 out_8(®s->canbtr1, btr1);
590 static int mscan_open(struct net_device *dev)
593 struct mscan_priv *priv = netdev_priv(dev);
594 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
597 ret = open_candev(dev);
601 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
602 napi_enable(&priv->napi);
605 ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev);
607 dev_err(ND2D(dev), "failed to attach interrupt\n");
608 goto exit_napi_disable;
611 priv->open_time = jiffies;
613 clrbits8(®s->canctl1, MSCAN_LISTEN);
615 ret = mscan_start(dev);
619 netif_start_queue(dev);
625 free_irq(dev->irq, dev);
627 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
628 napi_disable(&priv->napi);
634 static int mscan_close(struct net_device *dev)
636 struct mscan_priv *priv = netdev_priv(dev);
637 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
639 netif_stop_queue(dev);
640 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
641 napi_disable(&priv->napi);
644 out_8(®s->cantier, 0);
645 out_8(®s->canrier, 0);
646 mscan_set_mode(dev, MSCAN_INIT_MODE);
648 free_irq(dev->irq, dev);
654 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
655 static const struct net_device_ops mscan_netdev_ops = {
656 .ndo_open = mscan_open,
657 .ndo_stop = mscan_close,
658 .ndo_start_xmit = mscan_start_xmit,
662 int register_mscandev(struct net_device *dev, int clock_src)
664 struct mscan_priv *priv = netdev_priv(dev);
665 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
668 ctl1 = in_8(®s->canctl1);
670 ctl1 |= MSCAN_CLKSRC;
672 ctl1 &= ~MSCAN_CLKSRC;
675 out_8(®s->canctl1, ctl1);
678 /* acceptance mask/acceptance code (accept everything) */
679 out_be16(®s->canidar1_0, 0);
680 out_be16(®s->canidar3_2, 0);
681 out_be16(®s->canidar5_4, 0);
682 out_be16(®s->canidar7_6, 0);
684 out_be16(®s->canidmr1_0, 0xffff);
685 out_be16(®s->canidmr3_2, 0xffff);
686 out_be16(®s->canidmr5_4, 0xffff);
687 out_be16(®s->canidmr7_6, 0xffff);
688 /* Two 32 bit Acceptance Filters */
689 out_8(®s->canidac, MSCAN_AF_32BIT);
691 mscan_set_mode(dev, MSCAN_INIT_MODE);
693 return register_candev(dev);
696 void unregister_mscandev(struct net_device *dev)
698 struct mscan_priv *priv = netdev_priv(dev);
699 struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
700 mscan_set_mode(dev, MSCAN_INIT_MODE);
701 clrbits8(®s->canctl1, MSCAN_CANE);
702 unregister_candev(dev);
705 struct net_device *alloc_mscandev(void)
707 struct net_device *dev;
708 struct mscan_priv *priv;
711 dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX);
714 priv = netdev_priv(dev);
716 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
717 dev->netdev_ops = &mscan_netdev_ops;
719 dev->open = mscan_open;
720 dev->stop = mscan_close;
721 dev->hard_start_xmit = mscan_start_xmit;
724 dev->flags |= IFF_ECHO; /* we support local echo */
726 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
727 netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8);
728 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
730 netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8);
732 dev->poll = mscan_rx_poll;
736 priv->can.bittiming_const = &mscan_bittiming_const;
737 priv->can.do_set_bittiming = mscan_do_set_bittiming;
738 priv->can.do_set_mode = mscan_do_set_mode;
740 for (i = 0; i < TX_QUEUE_SIZE; i++) {
741 priv->tx_queue[i].id = i;
742 priv->tx_queue[i].mask = 1 << i;
748 MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>");
749 MODULE_LICENSE("GPL v2");
750 MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips");