1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2008-2010
5 * - Kurt Van Dijck, EIA Electronics
8 #include <linux/ethtool.h>
9 #include <linux/module.h>
10 #include <linux/interrupt.h>
15 #define TX_ECHO_SKB_MAX (((TXMAX+1)/2)-1)
18 * test is a specific CAN netdev
19 * is online (ie. up 'n running, not sleeping, not busoff
21 static inline int canif_is_active(struct net_device *netdev)
23 struct can_priv *can = netdev_priv(netdev);
25 if (!netif_running(netdev))
27 return (can->state <= CAN_STATE_ERROR_PASSIVE);
31 static inline void softing_set_reset_dpram(struct softing *card)
33 if (card->pdat->generation >= 2) {
34 spin_lock_bh(&card->spin);
35 iowrite8(ioread8(&card->dpram[DPRAM_V2_RESET]) & ~1,
36 &card->dpram[DPRAM_V2_RESET]);
37 spin_unlock_bh(&card->spin);
41 static inline void softing_clr_reset_dpram(struct softing *card)
43 if (card->pdat->generation >= 2) {
44 spin_lock_bh(&card->spin);
45 iowrite8(ioread8(&card->dpram[DPRAM_V2_RESET]) | 1,
46 &card->dpram[DPRAM_V2_RESET]);
47 spin_unlock_bh(&card->spin);
51 /* trigger the tx queue-ing */
52 static netdev_tx_t softing_netdev_start_xmit(struct sk_buff *skb,
53 struct net_device *dev)
55 struct softing_priv *priv = netdev_priv(dev);
56 struct softing *card = priv->card;
59 uint8_t fifo_wr, fifo_rd;
60 struct can_frame *cf = (struct can_frame *)skb->data;
61 uint8_t buf[DPRAM_TX_SIZE];
63 if (can_dropped_invalid_skb(dev, skb))
66 spin_lock(&card->spin);
70 (card->tx.pending >= TXMAX) ||
71 (priv->tx.pending >= TX_ECHO_SKB_MAX))
73 fifo_wr = ioread8(&card->dpram[DPRAM_TX_WR]);
74 fifo_rd = ioread8(&card->dpram[DPRAM_TX_RD]);
75 if (fifo_wr == fifo_rd)
78 memset(buf, 0, sizeof(buf));
81 if (cf->can_id & CAN_RTR_FLAG)
83 if (cf->can_id & CAN_EFF_FLAG)
89 *ptr++ = (cf->can_id >> 0);
90 *ptr++ = (cf->can_id >> 8);
91 if (cf->can_id & CAN_EFF_FLAG) {
92 *ptr++ = (cf->can_id >> 16);
93 *ptr++ = (cf->can_id >> 24);
95 /* increment 1, not 2 as you might think */
98 if (!(cf->can_id & CAN_RTR_FLAG))
99 memcpy(ptr, &cf->data[0], cf->len);
100 memcpy_toio(&card->dpram[DPRAM_TX + DPRAM_TX_SIZE * fifo_wr],
102 if (++fifo_wr >= DPRAM_TX_CNT)
104 iowrite8(fifo_wr, &card->dpram[DPRAM_TX_WR]);
105 card->tx.last_bus = priv->index;
108 can_put_echo_skb(skb, dev, priv->tx.echo_put, 0);
110 if (priv->tx.echo_put >= TX_ECHO_SKB_MAX)
111 priv->tx.echo_put = 0;
112 /* can_put_echo_skb() saves the skb, safe to return TX_OK */
115 spin_unlock(&card->spin);
116 if (card->tx.pending >= TXMAX) {
118 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
120 netif_stop_queue(card->net[j]);
123 if (ret != NETDEV_TX_OK)
124 netif_stop_queue(dev);
130 * shortcut for skb delivery
132 int softing_netdev_rx(struct net_device *netdev, const struct can_frame *msg,
136 struct can_frame *cf;
138 skb = alloc_can_skb(netdev, &cf);
141 memcpy(cf, msg, sizeof(*msg));
143 return netif_rx(skb);
148 * pop 1 entry from the DPRAM queue, and process
150 static int softing_handle_1(struct softing *card)
152 struct net_device *netdev;
153 struct softing_priv *priv;
155 struct can_frame msg;
156 int cnt = 0, lost_msg;
157 uint8_t fifo_rd, fifo_wr, cmd;
160 uint8_t buf[DPRAM_RX_SIZE];
162 memset(&msg, 0, sizeof(msg));
163 /* test for lost msgs */
164 lost_msg = ioread8(&card->dpram[DPRAM_RX_LOST]);
167 /* reset condition */
168 iowrite8(0, &card->dpram[DPRAM_RX_LOST]);
170 msg.can_id = CAN_ERR_FLAG | CAN_ERR_CRTL;
171 msg.len = CAN_ERR_DLC;
172 msg.data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
174 * service to all buses, we don't know which it was applicable
175 * but only service buses that are online
177 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
178 netdev = card->net[j];
181 if (!canif_is_active(netdev))
182 /* a dead bus has no overflows */
184 ++netdev->stats.rx_over_errors;
185 softing_netdev_rx(netdev, &msg, 0);
187 /* prepare for other use */
188 memset(&msg, 0, sizeof(msg));
192 fifo_rd = ioread8(&card->dpram[DPRAM_RX_RD]);
193 fifo_wr = ioread8(&card->dpram[DPRAM_RX_WR]);
195 if (++fifo_rd >= DPRAM_RX_CNT)
197 if (fifo_wr == fifo_rd)
200 memcpy_fromio(buf, &card->dpram[DPRAM_RX + DPRAM_RX_SIZE*fifo_rd],
203 /* trigger dual port RAM */
204 iowrite8(fifo_rd, &card->dpram[DPRAM_RX_RD]);
209 /* not quite useful, probably the card has got out */
211 netdev = card->net[0];
213 netdev = card->net[1];
214 priv = netdev_priv(netdev);
217 uint8_t can_state, state;
221 msg.can_id = CAN_ERR_FLAG;
222 msg.len = CAN_ERR_DLC;
224 if (state & SF_MASK_BUSOFF) {
225 can_state = CAN_STATE_BUS_OFF;
226 msg.can_id |= CAN_ERR_BUSOFF;
227 state = STATE_BUSOFF;
228 } else if (state & SF_MASK_EPASSIVE) {
229 can_state = CAN_STATE_ERROR_PASSIVE;
230 msg.can_id |= CAN_ERR_CRTL;
231 msg.data[1] = CAN_ERR_CRTL_TX_PASSIVE;
232 state = STATE_EPASSIVE;
234 can_state = CAN_STATE_ERROR_ACTIVE;
235 msg.can_id |= CAN_ERR_CRTL;
236 state = STATE_EACTIVE;
239 iowrite8(state, &card->dpram[priv->index ?
240 DPRAM_INFO_BUSSTATE2 : DPRAM_INFO_BUSSTATE]);
242 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.len = can_cc_dlc2len(*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);
281 /* acknowledge, was tx msg */
283 skb = priv->can.echo_skb[priv->tx.echo_get];
286 ++netdev->stats.tx_packets;
287 netdev->stats.tx_bytes +=
288 can_get_echo_skb(netdev, priv->tx.echo_get,
291 if (priv->tx.echo_get >= TX_ECHO_SKB_MAX)
292 priv->tx.echo_get = 0;
293 if (priv->tx.pending)
295 if (card->tx.pending)
300 ret = softing_netdev_rx(netdev, &msg, ktime);
301 if (ret == NET_RX_SUCCESS) {
302 ++netdev->stats.rx_packets;
303 if (!(msg.can_id & CAN_RTR_FLAG))
304 netdev->stats.rx_bytes += msg.len;
306 ++netdev->stats.rx_dropped;
315 * real interrupt handler
317 static irqreturn_t softing_irq_thread(int irq, void *dev_id)
319 struct softing *card = (struct softing *)dev_id;
320 struct net_device *netdev;
321 struct softing_priv *priv;
322 int j, offset, work_done;
325 spin_lock_bh(&card->spin);
326 while (softing_handle_1(card) > 0) {
327 ++card->irq.svc_count;
330 spin_unlock_bh(&card->spin);
331 /* resume tx queue's */
332 offset = card->tx.last_bus;
333 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
334 if (card->tx.pending >= TXMAX)
336 netdev = card->net[(j + offset + 1) % card->pdat->nbus];
339 priv = netdev_priv(netdev);
340 if (!canif_is_active(netdev))
341 /* it makes no sense to wake dead buses */
343 if (priv->tx.pending >= TX_ECHO_SKB_MAX)
346 netif_wake_queue(netdev);
348 return work_done ? IRQ_HANDLED : IRQ_NONE;
352 * interrupt routines:
353 * schedule the 'real interrupt handler'
355 static irqreturn_t softing_irq_v2(int irq, void *dev_id)
357 struct softing *card = (struct softing *)dev_id;
360 ir = ioread8(&card->dpram[DPRAM_V2_IRQ_TOHOST]);
361 iowrite8(0, &card->dpram[DPRAM_V2_IRQ_TOHOST]);
362 return (1 == ir) ? IRQ_WAKE_THREAD : IRQ_NONE;
365 static irqreturn_t softing_irq_v1(int irq, void *dev_id)
367 struct softing *card = (struct softing *)dev_id;
370 ir = ioread8(&card->dpram[DPRAM_IRQ_TOHOST]);
371 iowrite8(0, &card->dpram[DPRAM_IRQ_TOHOST]);
372 return ir ? IRQ_WAKE_THREAD : IRQ_NONE;
376 * netdev/candev interoperability
378 static int softing_netdev_open(struct net_device *ndev)
382 /* check or determine and set bittime */
383 ret = open_candev(ndev);
387 ret = softing_startstop(ndev, 1);
394 static int softing_netdev_stop(struct net_device *ndev)
396 netif_stop_queue(ndev);
398 /* softing cycle does close_candev() */
399 return softing_startstop(ndev, 0);
402 static int softing_candev_set_mode(struct net_device *ndev, enum can_mode mode)
408 /* softing_startstop does close_candev() */
409 ret = softing_startstop(ndev, 1);
419 * Softing device management helpers
421 int softing_enable_irq(struct softing *card, int enable)
427 } else if (card->irq.requested && !enable) {
428 free_irq(card->irq.nr, card);
429 card->irq.requested = 0;
430 } else if (!card->irq.requested && enable) {
431 ret = request_threaded_irq(card->irq.nr,
432 (card->pdat->generation >= 2) ?
433 softing_irq_v2 : softing_irq_v1,
434 softing_irq_thread, IRQF_SHARED,
435 dev_name(&card->pdev->dev), card);
437 dev_alert(&card->pdev->dev,
438 "request_threaded_irq(%u) failed\n",
442 card->irq.requested = 1;
447 static void softing_card_shutdown(struct softing *card)
451 if (mutex_lock_interruptible(&card->fw.lock)) {
452 /* return -ERESTARTSYS */;
457 if (card->irq.requested && card->irq.nr) {
458 free_irq(card->irq.nr, card);
459 card->irq.requested = 0;
462 if (card->pdat->enable_irq)
463 card->pdat->enable_irq(card->pdev, 0);
464 softing_set_reset_dpram(card);
465 if (card->pdat->reset)
466 card->pdat->reset(card->pdev, 1);
468 mutex_unlock(&card->fw.lock);
471 static int softing_card_boot(struct softing *card)
474 static const uint8_t stream[] = {
475 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, };
476 unsigned char back[sizeof(stream)];
478 if (mutex_lock_interruptible(&card->fw.lock))
481 mutex_unlock(&card->fw.lock);
485 if (card->pdat->enable_irq)
486 card->pdat->enable_irq(card->pdev, 1);
488 softing_set_reset_dpram(card);
489 if (card->pdat->reset)
490 card->pdat->reset(card->pdev, 1);
491 for (j = 0; (j + sizeof(stream)) < card->dpram_size;
492 j += sizeof(stream)) {
494 memcpy_toio(&card->dpram[j], stream, sizeof(stream));
497 memcpy_fromio(back, &card->dpram[j], sizeof(stream));
499 if (!memcmp(back, stream, sizeof(stream)))
501 /* memory is not equal */
502 dev_alert(&card->pdev->dev, "dpram failed at 0x%04x\n", j);
507 /* load boot firmware */
508 ret = softing_load_fw(card->pdat->boot.fw, card, card->dpram,
510 card->pdat->boot.offs - card->pdat->boot.addr);
513 /* load loader firmware */
514 ret = softing_load_fw(card->pdat->load.fw, card, card->dpram,
516 card->pdat->load.offs - card->pdat->load.addr);
520 if (card->pdat->reset)
521 card->pdat->reset(card->pdev, 0);
522 softing_clr_reset_dpram(card);
523 ret = softing_bootloader_command(card, 0, "card boot");
526 ret = softing_load_app_fw(card->pdat->app.fw, card);
530 ret = softing_chip_poweron(card);
535 mutex_unlock(&card->fw.lock);
539 if (card->pdat->enable_irq)
540 card->pdat->enable_irq(card->pdev, 0);
541 softing_set_reset_dpram(card);
542 if (card->pdat->reset)
543 card->pdat->reset(card->pdev, 1);
544 mutex_unlock(&card->fw.lock);
551 static ssize_t show_chip(struct device *dev, struct device_attribute *attr,
554 struct net_device *ndev = to_net_dev(dev);
555 struct softing_priv *priv = netdev2softing(ndev);
557 return sprintf(buf, "%i\n", priv->chip);
560 static ssize_t show_output(struct device *dev, struct device_attribute *attr,
563 struct net_device *ndev = to_net_dev(dev);
564 struct softing_priv *priv = netdev2softing(ndev);
566 return sprintf(buf, "0x%02x\n", priv->output);
569 static ssize_t store_output(struct device *dev, struct device_attribute *attr,
570 const char *buf, size_t count)
572 struct net_device *ndev = to_net_dev(dev);
573 struct softing_priv *priv = netdev2softing(ndev);
574 struct softing *card = priv->card;
578 ret = kstrtoul(buf, 0, &val);
583 ret = mutex_lock_interruptible(&card->fw.lock);
586 if (netif_running(ndev)) {
587 mutex_unlock(&card->fw.lock);
591 mutex_unlock(&card->fw.lock);
595 static const DEVICE_ATTR(chip, 0444, show_chip, NULL);
596 static const DEVICE_ATTR(output, 0644, show_output, store_output);
598 static const struct attribute *const netdev_sysfs_attrs[] = {
600 &dev_attr_output.attr,
603 static const struct attribute_group netdev_sysfs_group = {
605 .attrs = (struct attribute **)netdev_sysfs_attrs,
608 static const struct net_device_ops softing_netdev_ops = {
609 .ndo_open = softing_netdev_open,
610 .ndo_stop = softing_netdev_stop,
611 .ndo_start_xmit = softing_netdev_start_xmit,
612 .ndo_change_mtu = can_change_mtu,
615 static const struct ethtool_ops softing_ethtool_ops = {
616 .get_ts_info = ethtool_op_get_ts_info,
619 static const struct can_bittiming_const softing_btr_const = {
620 .name = KBUILD_MODNAME,
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 netdev->ethtool_ops = &softing_ethtool_ops;
658 priv->can.do_set_mode = softing_candev_set_mode;
659 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
664 static int softing_netdev_register(struct net_device *netdev)
668 ret = register_candev(netdev);
670 dev_alert(&netdev->dev, "register failed\n");
673 if (sysfs_create_group(&netdev->dev.kobj, &netdev_sysfs_group) < 0)
674 netdev_alert(netdev, "sysfs group failed\n");
679 static void softing_netdev_cleanup(struct net_device *netdev)
681 sysfs_remove_group(&netdev->dev.kobj, &netdev_sysfs_group);
682 unregister_candev(netdev);
687 * sysfs for Platform device
689 #define DEV_ATTR_RO(name, member) \
690 static ssize_t show_##name(struct device *dev, \
691 struct device_attribute *attr, char *buf) \
693 struct softing *card = dev_get_drvdata(dev); \
694 return sprintf(buf, "%u\n", card->member); \
696 static DEVICE_ATTR(name, 0444, show_##name, NULL)
698 #define DEV_ATTR_RO_STR(name, member) \
699 static ssize_t show_##name(struct device *dev, \
700 struct device_attribute *attr, char *buf) \
702 struct softing *card = dev_get_drvdata(dev); \
703 return sprintf(buf, "%s\n", card->member); \
705 static DEVICE_ATTR(name, 0444, show_##name, NULL)
707 DEV_ATTR_RO(serial, id.serial);
708 DEV_ATTR_RO_STR(firmware, pdat->app.fw);
709 DEV_ATTR_RO(firmware_version, id.fw_version);
710 DEV_ATTR_RO_STR(hardware, pdat->name);
711 DEV_ATTR_RO(hardware_version, id.hw_version);
712 DEV_ATTR_RO(license, id.license);
714 static struct attribute *softing_pdev_attrs[] = {
715 &dev_attr_serial.attr,
716 &dev_attr_firmware.attr,
717 &dev_attr_firmware_version.attr,
718 &dev_attr_hardware.attr,
719 &dev_attr_hardware_version.attr,
720 &dev_attr_license.attr,
724 static const struct attribute_group softing_pdev_group = {
726 .attrs = softing_pdev_attrs,
732 static int softing_pdev_remove(struct platform_device *pdev)
734 struct softing *card = platform_get_drvdata(pdev);
737 /* first, disable card*/
738 softing_card_shutdown(card);
740 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
743 softing_netdev_cleanup(card->net[j]);
746 sysfs_remove_group(&pdev->dev.kobj, &softing_pdev_group);
748 iounmap(card->dpram);
753 static int softing_pdev_probe(struct platform_device *pdev)
755 const struct softing_platform_data *pdat = dev_get_platdata(&pdev->dev);
756 struct softing *card;
757 struct net_device *netdev;
758 struct softing_priv *priv;
759 struct resource *pres;
764 dev_warn(&pdev->dev, "no platform data\n");
767 if (pdat->nbus > ARRAY_SIZE(card->net)) {
768 dev_warn(&pdev->dev, "%u nets??\n", pdat->nbus);
772 card = kzalloc(sizeof(*card), GFP_KERNEL);
777 platform_set_drvdata(pdev, card);
778 mutex_init(&card->fw.lock);
779 spin_lock_init(&card->spin);
782 pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
784 goto platform_resource_failed;
785 card->dpram_phys = pres->start;
786 card->dpram_size = resource_size(pres);
787 card->dpram = ioremap(card->dpram_phys, card->dpram_size);
789 dev_alert(&card->pdev->dev, "dpram ioremap failed\n");
793 pres = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
795 card->irq.nr = pres->start;
798 ret = softing_card_boot(card);
800 dev_alert(&pdev->dev, "failed to boot\n");
804 /* only now, the chip's are known */
805 card->id.freq = card->pdat->freq;
807 ret = sysfs_create_group(&pdev->dev.kobj, &softing_pdev_group);
809 dev_alert(&card->pdev->dev, "sysfs failed\n");
813 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
814 card->net[j] = netdev =
815 softing_netdev_create(card, card->id.chip[j]);
817 dev_alert(&pdev->dev, "failed to make can[%i]", j);
822 priv = netdev_priv(card->net[j]);
824 ret = softing_netdev_register(netdev);
828 dev_alert(&card->pdev->dev,
829 "failed to register can[%i]\n", j);
833 dev_info(&card->pdev->dev, "%s ready.\n", card->pdat->name);
837 for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
840 softing_netdev_cleanup(card->net[j]);
842 sysfs_remove_group(&pdev->dev.kobj, &softing_pdev_group);
844 softing_card_shutdown(card);
846 iounmap(card->dpram);
848 platform_resource_failed:
853 static struct platform_driver softing_driver = {
855 .name = KBUILD_MODNAME,
857 .probe = softing_pdev_probe,
858 .remove = softing_pdev_remove,
861 module_platform_driver(softing_driver);
863 MODULE_ALIAS("platform:softing");
864 MODULE_DESCRIPTION("Softing DPRAM CAN driver");
866 MODULE_LICENSE("GPL v2");