1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2008-2010
5 * - Kurt Van Dijck, EIA Electronics
8 #include <linux/module.h>
9 #include <linux/interrupt.h>
14 #define TX_ECHO_SKB_MAX (((TXMAX+1)/2)-1)
17 * test is a specific CAN netdev
18 * is online (ie. up 'n running, not sleeping, not busoff
20 static inline int canif_is_active(struct net_device *netdev)
22 struct can_priv *can = netdev_priv(netdev);
24 if (!netif_running(netdev))
26 return (can->state <= CAN_STATE_ERROR_PASSIVE);
30 static inline void softing_set_reset_dpram(struct softing *card)
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);
40 static inline void softing_clr_reset_dpram(struct softing *card)
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);
50 /* trigger the tx queue-ing */
51 static netdev_tx_t softing_netdev_start_xmit(struct sk_buff *skb,
52 struct net_device *dev)
54 struct softing_priv *priv = netdev_priv(dev);
55 struct softing *card = priv->card;
58 uint8_t fifo_wr, fifo_rd;
59 struct can_frame *cf = (struct can_frame *)skb->data;
60 uint8_t buf[DPRAM_TX_SIZE];
62 if (can_dropped_invalid_skb(dev, skb))
65 spin_lock(&card->spin);
69 (card->tx.pending >= TXMAX) ||
70 (priv->tx.pending >= TX_ECHO_SKB_MAX))
72 fifo_wr = ioread8(&card->dpram[DPRAM_TX_WR]);
73 fifo_rd = ioread8(&card->dpram[DPRAM_TX_RD]);
74 if (fifo_wr == fifo_rd)
77 memset(buf, 0, sizeof(buf));
80 if (cf->can_id & CAN_RTR_FLAG)
82 if (cf->can_id & CAN_EFF_FLAG)
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);
94 /* increment 1, not 2 as you might think */
97 if (!(cf->can_id & CAN_RTR_FLAG))
98 memcpy(ptr, &cf->data[0], cf->can_dlc);
99 memcpy_toio(&card->dpram[DPRAM_TX + DPRAM_TX_SIZE * fifo_wr],
101 if (++fifo_wr >= DPRAM_TX_CNT)
103 iowrite8(fifo_wr, &card->dpram[DPRAM_TX_WR]);
104 card->tx.last_bus = priv->index;
107 can_put_echo_skb(skb, dev, 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 */
114 spin_unlock(&card->spin);
115 if (card->tx.pending >= TXMAX) {
117 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
119 netif_stop_queue(card->net[j]);
122 if (ret != NETDEV_TX_OK)
123 netif_stop_queue(dev);
129 * shortcut for skb delivery
131 int softing_netdev_rx(struct net_device *netdev, const struct can_frame *msg,
135 struct can_frame *cf;
137 skb = alloc_can_skb(netdev, &cf);
140 memcpy(cf, msg, sizeof(*msg));
142 return netif_rx(skb);
147 * pop 1 entry from the DPRAM queue, and process
149 static int softing_handle_1(struct softing *card)
151 struct net_device *netdev;
152 struct softing_priv *priv;
154 struct can_frame msg;
155 int cnt = 0, lost_msg;
156 uint8_t fifo_rd, fifo_wr, cmd;
159 uint8_t buf[DPRAM_RX_SIZE];
161 memset(&msg, 0, sizeof(msg));
162 /* test for lost msgs */
163 lost_msg = ioread8(&card->dpram[DPRAM_RX_LOST]);
166 /* reset condition */
167 iowrite8(0, &card->dpram[DPRAM_RX_LOST]);
169 msg.can_id = CAN_ERR_FLAG | CAN_ERR_CRTL;
170 msg.can_dlc = CAN_ERR_DLC;
171 msg.data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
173 * service to all buses, we don't know which it was applicable
174 * but only service buses that are online
176 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
177 netdev = card->net[j];
180 if (!canif_is_active(netdev))
181 /* a dead bus has no overflows */
183 ++netdev->stats.rx_over_errors;
184 softing_netdev_rx(netdev, &msg, 0);
186 /* prepare for other use */
187 memset(&msg, 0, sizeof(msg));
191 fifo_rd = ioread8(&card->dpram[DPRAM_RX_RD]);
192 fifo_wr = ioread8(&card->dpram[DPRAM_RX_WR]);
194 if (++fifo_rd >= DPRAM_RX_CNT)
196 if (fifo_wr == fifo_rd)
199 memcpy_fromio(buf, &card->dpram[DPRAM_RX + DPRAM_RX_SIZE*fifo_rd],
202 /* trigger dual port RAM */
203 iowrite8(fifo_rd, &card->dpram[DPRAM_RX_RD]);
208 /* not quite useful, probably the card has got out */
210 netdev = card->net[0];
212 netdev = card->net[1];
213 priv = netdev_priv(netdev);
216 uint8_t can_state, state;
220 msg.can_id = CAN_ERR_FLAG;
221 msg.can_dlc = CAN_ERR_DLC;
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;
233 can_state = CAN_STATE_ERROR_ACTIVE;
234 msg.can_id |= CAN_ERR_CRTL;
235 state = STATE_EACTIVE;
238 iowrite8(state, &card->dpram[priv->index ?
239 DPRAM_INFO_BUSSTATE2 : DPRAM_INFO_BUSSTATE]);
241 tmp_u32 = le32_to_cpup((void *)ptr);
243 ktime = softing_raw2ktime(card, tmp_u32);
245 ++netdev->stats.rx_errors;
246 /* update internal status */
247 if (can_state != priv->can.state) {
248 priv->can.state = can_state;
249 if (can_state == CAN_STATE_ERROR_PASSIVE)
250 ++priv->can.can_stats.error_passive;
251 else if (can_state == CAN_STATE_BUS_OFF) {
252 /* this calls can_close_cleanup() */
253 ++priv->can.can_stats.bus_off;
255 netif_stop_queue(netdev);
257 /* trigger socketcan */
258 softing_netdev_rx(netdev, &msg, ktime);
263 msg.can_id |= CAN_RTR_FLAG;
264 msg.can_dlc = get_can_dlc(*ptr++);
266 msg.can_id |= CAN_EFF_FLAG;
267 msg.can_id |= le32_to_cpup((void *)ptr);
270 msg.can_id |= le16_to_cpup((void *)ptr);
274 tmp_u32 = le32_to_cpup((void *)ptr);
276 ktime = softing_raw2ktime(card, tmp_u32);
277 if (!(msg.can_id & CAN_RTR_FLAG))
278 memcpy(&msg.data[0], ptr, 8);
282 /* acknowledge, was tx msg */
284 skb = priv->can.echo_skb[priv->tx.echo_get];
287 can_get_echo_skb(netdev, priv->tx.echo_get);
289 if (priv->tx.echo_get >= TX_ECHO_SKB_MAX)
290 priv->tx.echo_get = 0;
291 if (priv->tx.pending)
293 if (card->tx.pending)
295 ++netdev->stats.tx_packets;
296 if (!(msg.can_id & CAN_RTR_FLAG))
297 netdev->stats.tx_bytes += msg.can_dlc;
301 ret = softing_netdev_rx(netdev, &msg, ktime);
302 if (ret == NET_RX_SUCCESS) {
303 ++netdev->stats.rx_packets;
304 if (!(msg.can_id & CAN_RTR_FLAG))
305 netdev->stats.rx_bytes += msg.can_dlc;
307 ++netdev->stats.rx_dropped;
316 * real interrupt handler
318 static irqreturn_t softing_irq_thread(int irq, void *dev_id)
320 struct softing *card = (struct softing *)dev_id;
321 struct net_device *netdev;
322 struct softing_priv *priv;
323 int j, offset, work_done;
326 spin_lock_bh(&card->spin);
327 while (softing_handle_1(card) > 0) {
328 ++card->irq.svc_count;
331 spin_unlock_bh(&card->spin);
332 /* resume tx queue's */
333 offset = card->tx.last_bus;
334 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
335 if (card->tx.pending >= TXMAX)
337 netdev = card->net[(j + offset + 1) % card->pdat->nbus];
340 priv = netdev_priv(netdev);
341 if (!canif_is_active(netdev))
342 /* it makes no sense to wake dead buses */
344 if (priv->tx.pending >= TX_ECHO_SKB_MAX)
347 netif_wake_queue(netdev);
349 return work_done ? IRQ_HANDLED : IRQ_NONE;
353 * interrupt routines:
354 * schedule the 'real interrupt handler'
356 static irqreturn_t softing_irq_v2(int irq, void *dev_id)
358 struct softing *card = (struct softing *)dev_id;
361 ir = ioread8(&card->dpram[DPRAM_V2_IRQ_TOHOST]);
362 iowrite8(0, &card->dpram[DPRAM_V2_IRQ_TOHOST]);
363 return (1 == ir) ? IRQ_WAKE_THREAD : IRQ_NONE;
366 static irqreturn_t softing_irq_v1(int irq, void *dev_id)
368 struct softing *card = (struct softing *)dev_id;
371 ir = ioread8(&card->dpram[DPRAM_IRQ_TOHOST]);
372 iowrite8(0, &card->dpram[DPRAM_IRQ_TOHOST]);
373 return ir ? IRQ_WAKE_THREAD : IRQ_NONE;
377 * netdev/candev interoperability
379 static int softing_netdev_open(struct net_device *ndev)
383 /* check or determine and set bittime */
384 ret = open_candev(ndev);
388 ret = softing_startstop(ndev, 1);
395 static int softing_netdev_stop(struct net_device *ndev)
399 netif_stop_queue(ndev);
401 /* softing cycle does close_candev() */
402 ret = softing_startstop(ndev, 0);
406 static int softing_candev_set_mode(struct net_device *ndev, enum can_mode mode)
412 /* softing_startstop does close_candev() */
413 ret = softing_startstop(ndev, 1);
423 * Softing device management helpers
425 int softing_enable_irq(struct softing *card, int enable)
431 } else if (card->irq.requested && !enable) {
432 free_irq(card->irq.nr, card);
433 card->irq.requested = 0;
434 } else if (!card->irq.requested && enable) {
435 ret = request_threaded_irq(card->irq.nr,
436 (card->pdat->generation >= 2) ?
437 softing_irq_v2 : softing_irq_v1,
438 softing_irq_thread, IRQF_SHARED,
439 dev_name(&card->pdev->dev), card);
441 dev_alert(&card->pdev->dev,
442 "request_threaded_irq(%u) failed\n",
446 card->irq.requested = 1;
451 static void softing_card_shutdown(struct softing *card)
455 if (mutex_lock_interruptible(&card->fw.lock)) {
456 /* return -ERESTARTSYS */;
461 if (card->irq.requested && card->irq.nr) {
462 free_irq(card->irq.nr, card);
463 card->irq.requested = 0;
466 if (card->pdat->enable_irq)
467 card->pdat->enable_irq(card->pdev, 0);
468 softing_set_reset_dpram(card);
469 if (card->pdat->reset)
470 card->pdat->reset(card->pdev, 1);
472 mutex_unlock(&card->fw.lock);
475 static int softing_card_boot(struct softing *card)
478 static const uint8_t stream[] = {
479 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, };
480 unsigned char back[sizeof(stream)];
482 if (mutex_lock_interruptible(&card->fw.lock))
485 mutex_unlock(&card->fw.lock);
489 if (card->pdat->enable_irq)
490 card->pdat->enable_irq(card->pdev, 1);
492 softing_set_reset_dpram(card);
493 if (card->pdat->reset)
494 card->pdat->reset(card->pdev, 1);
495 for (j = 0; (j + sizeof(stream)) < card->dpram_size;
496 j += sizeof(stream)) {
498 memcpy_toio(&card->dpram[j], stream, sizeof(stream));
501 memcpy_fromio(back, &card->dpram[j], sizeof(stream));
503 if (!memcmp(back, stream, sizeof(stream)))
505 /* memory is not equal */
506 dev_alert(&card->pdev->dev, "dpram failed at 0x%04x\n", j);
511 /* load boot firmware */
512 ret = softing_load_fw(card->pdat->boot.fw, card, card->dpram,
514 card->pdat->boot.offs - card->pdat->boot.addr);
517 /* load loader firmware */
518 ret = softing_load_fw(card->pdat->load.fw, card, card->dpram,
520 card->pdat->load.offs - card->pdat->load.addr);
524 if (card->pdat->reset)
525 card->pdat->reset(card->pdev, 0);
526 softing_clr_reset_dpram(card);
527 ret = softing_bootloader_command(card, 0, "card boot");
530 ret = softing_load_app_fw(card->pdat->app.fw, card);
534 ret = softing_chip_poweron(card);
539 mutex_unlock(&card->fw.lock);
543 if (card->pdat->enable_irq)
544 card->pdat->enable_irq(card->pdev, 0);
545 softing_set_reset_dpram(card);
546 if (card->pdat->reset)
547 card->pdat->reset(card->pdev, 1);
548 mutex_unlock(&card->fw.lock);
555 static ssize_t show_chip(struct device *dev, struct device_attribute *attr,
558 struct net_device *ndev = to_net_dev(dev);
559 struct softing_priv *priv = netdev2softing(ndev);
561 return sprintf(buf, "%i\n", priv->chip);
564 static ssize_t show_output(struct device *dev, struct device_attribute *attr,
567 struct net_device *ndev = to_net_dev(dev);
568 struct softing_priv *priv = netdev2softing(ndev);
570 return sprintf(buf, "0x%02x\n", priv->output);
573 static ssize_t store_output(struct device *dev, struct device_attribute *attr,
574 const char *buf, size_t count)
576 struct net_device *ndev = to_net_dev(dev);
577 struct softing_priv *priv = netdev2softing(ndev);
578 struct softing *card = priv->card;
582 ret = kstrtoul(buf, 0, &val);
587 ret = mutex_lock_interruptible(&card->fw.lock);
590 if (netif_running(ndev)) {
591 mutex_unlock(&card->fw.lock);
595 mutex_unlock(&card->fw.lock);
599 static const DEVICE_ATTR(chip, 0444, show_chip, NULL);
600 static const DEVICE_ATTR(output, 0644, show_output, store_output);
602 static const struct attribute *const netdev_sysfs_attrs[] = {
604 &dev_attr_output.attr,
607 static const struct attribute_group netdev_sysfs_group = {
609 .attrs = (struct attribute **)netdev_sysfs_attrs,
612 static const struct net_device_ops softing_netdev_ops = {
613 .ndo_open = softing_netdev_open,
614 .ndo_stop = softing_netdev_stop,
615 .ndo_start_xmit = softing_netdev_start_xmit,
616 .ndo_change_mtu = can_change_mtu,
619 static const struct can_bittiming_const softing_btr_const = {
625 .sjw_max = 4, /* overruled */
627 .brp_max = 32, /* overruled */
632 static struct net_device *softing_netdev_create(struct softing *card,
635 struct net_device *netdev;
636 struct softing_priv *priv;
638 netdev = alloc_candev(sizeof(*priv), TX_ECHO_SKB_MAX);
640 dev_alert(&card->pdev->dev, "alloc_candev failed\n");
643 priv = netdev_priv(netdev);
644 priv->netdev = netdev;
646 memcpy(&priv->btr_const, &softing_btr_const, sizeof(priv->btr_const));
647 priv->btr_const.brp_max = card->pdat->max_brp;
648 priv->btr_const.sjw_max = card->pdat->max_sjw;
649 priv->can.bittiming_const = &priv->btr_const;
650 priv->can.clock.freq = 8000000;
651 priv->chip = chip_id;
652 priv->output = softing_default_output(netdev);
653 SET_NETDEV_DEV(netdev, &card->pdev->dev);
655 netdev->flags |= IFF_ECHO;
656 netdev->netdev_ops = &softing_netdev_ops;
657 priv->can.do_set_mode = softing_candev_set_mode;
658 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
663 static int softing_netdev_register(struct net_device *netdev)
667 ret = register_candev(netdev);
669 dev_alert(&netdev->dev, "register failed\n");
672 if (sysfs_create_group(&netdev->dev.kobj, &netdev_sysfs_group) < 0)
673 netdev_alert(netdev, "sysfs group failed\n");
678 static void softing_netdev_cleanup(struct net_device *netdev)
680 sysfs_remove_group(&netdev->dev.kobj, &netdev_sysfs_group);
681 unregister_candev(netdev);
686 * sysfs for Platform device
688 #define DEV_ATTR_RO(name, member) \
689 static ssize_t show_##name(struct device *dev, \
690 struct device_attribute *attr, char *buf) \
692 struct softing *card = dev_get_drvdata(dev); \
693 return sprintf(buf, "%u\n", card->member); \
695 static DEVICE_ATTR(name, 0444, show_##name, NULL)
697 #define DEV_ATTR_RO_STR(name, member) \
698 static ssize_t show_##name(struct device *dev, \
699 struct device_attribute *attr, char *buf) \
701 struct softing *card = dev_get_drvdata(dev); \
702 return sprintf(buf, "%s\n", card->member); \
704 static DEVICE_ATTR(name, 0444, show_##name, NULL)
706 DEV_ATTR_RO(serial, id.serial);
707 DEV_ATTR_RO_STR(firmware, pdat->app.fw);
708 DEV_ATTR_RO(firmware_version, id.fw_version);
709 DEV_ATTR_RO_STR(hardware, pdat->name);
710 DEV_ATTR_RO(hardware_version, id.hw_version);
711 DEV_ATTR_RO(license, id.license);
713 static struct attribute *softing_pdev_attrs[] = {
714 &dev_attr_serial.attr,
715 &dev_attr_firmware.attr,
716 &dev_attr_firmware_version.attr,
717 &dev_attr_hardware.attr,
718 &dev_attr_hardware_version.attr,
719 &dev_attr_license.attr,
723 static const struct attribute_group softing_pdev_group = {
725 .attrs = softing_pdev_attrs,
731 static int softing_pdev_remove(struct platform_device *pdev)
733 struct softing *card = platform_get_drvdata(pdev);
736 /* first, disable card*/
737 softing_card_shutdown(card);
739 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
742 softing_netdev_cleanup(card->net[j]);
745 sysfs_remove_group(&pdev->dev.kobj, &softing_pdev_group);
747 iounmap(card->dpram);
752 static int softing_pdev_probe(struct platform_device *pdev)
754 const struct softing_platform_data *pdat = dev_get_platdata(&pdev->dev);
755 struct softing *card;
756 struct net_device *netdev;
757 struct softing_priv *priv;
758 struct resource *pres;
763 dev_warn(&pdev->dev, "no platform data\n");
766 if (pdat->nbus > ARRAY_SIZE(card->net)) {
767 dev_warn(&pdev->dev, "%u nets??\n", pdat->nbus);
771 card = kzalloc(sizeof(*card), GFP_KERNEL);
776 platform_set_drvdata(pdev, card);
777 mutex_init(&card->fw.lock);
778 spin_lock_init(&card->spin);
781 pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
783 goto platform_resource_failed;
784 card->dpram_phys = pres->start;
785 card->dpram_size = resource_size(pres);
786 card->dpram = ioremap(card->dpram_phys, card->dpram_size);
788 dev_alert(&card->pdev->dev, "dpram ioremap failed\n");
792 pres = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
794 card->irq.nr = pres->start;
797 ret = softing_card_boot(card);
799 dev_alert(&pdev->dev, "failed to boot\n");
803 /* only now, the chip's are known */
804 card->id.freq = card->pdat->freq;
806 ret = sysfs_create_group(&pdev->dev.kobj, &softing_pdev_group);
808 dev_alert(&card->pdev->dev, "sysfs failed\n");
812 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
813 card->net[j] = netdev =
814 softing_netdev_create(card, card->id.chip[j]);
816 dev_alert(&pdev->dev, "failed to make can[%i]", j);
821 priv = netdev_priv(card->net[j]);
823 ret = softing_netdev_register(netdev);
827 dev_alert(&card->pdev->dev,
828 "failed to register can[%i]\n", j);
832 dev_info(&card->pdev->dev, "%s ready.\n", card->pdat->name);
836 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
839 softing_netdev_cleanup(card->net[j]);
841 sysfs_remove_group(&pdev->dev.kobj, &softing_pdev_group);
843 softing_card_shutdown(card);
845 iounmap(card->dpram);
847 platform_resource_failed:
852 static struct platform_driver softing_driver = {
856 .probe = softing_pdev_probe,
857 .remove = softing_pdev_remove,
860 module_platform_driver(softing_driver);
862 MODULE_ALIAS("platform:softing");
863 MODULE_DESCRIPTION("Softing DPRAM CAN driver");
864 MODULE_AUTHOR("Kurt Van Dijck <kurt.van.dijck@eia.be>");
865 MODULE_LICENSE("GPL v2");