can: add driver for Softing card

This patch adds a driver for the platform:softing device.
This will create (up to) 2 CAN network devices from 1
platform:softing device

Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/can/softing/softing_fw.c b/drivers/net/can/softing/softing_fw.c
new file mode 100644
index 0000000..b520784
--- /dev/null
+++ b/drivers/net/can/softing/softing_fw.c
@@ -0,0 +1,691 @@
+/*
+ * Copyright (C) 2008-2010
+ *
+ * - Kurt Van Dijck, EIA Electronics
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the version 2 of the GNU General Public License
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/firmware.h>
+#include <linux/sched.h>
+#include <asm/div64.h>
+
+#include "softing.h"
+
+/*
+ * low level DPRAM command.
+ * Make sure that card->dpram[DPRAM_FCT_HOST] is preset
+ */
+static int _softing_fct_cmd(struct softing *card, int16_t cmd, uint16_t vector,
+		const char *msg)
+{
+	int ret;
+	unsigned long stamp;
+
+	iowrite16(cmd, &card->dpram[DPRAM_FCT_PARAM]);
+	iowrite8(vector >> 8, &card->dpram[DPRAM_FCT_HOST + 1]);
+	iowrite8(vector, &card->dpram[DPRAM_FCT_HOST]);
+	/* be sure to flush this to the card */
+	wmb();
+	stamp = jiffies + 1 * HZ;
+	/* wait for card */
+	do {
+		/* DPRAM_FCT_HOST is _not_ aligned */
+		ret = ioread8(&card->dpram[DPRAM_FCT_HOST]) +
+			(ioread8(&card->dpram[DPRAM_FCT_HOST + 1]) << 8);
+		/* don't have any cached variables */
+		rmb();
+		if (ret == RES_OK)
+			/* read return-value now */
+			return ioread16(&card->dpram[DPRAM_FCT_RESULT]);
+
+		if ((ret != vector) || time_after(jiffies, stamp))
+			break;
+		/* process context => relax */
+		usleep_range(500, 10000);
+	} while (1);
+
+	ret = (ret == RES_NONE) ? -ETIMEDOUT : -ECANCELED;
+	dev_alert(&card->pdev->dev, "firmware %s failed (%i)\n", msg, ret);
+	return ret;
+}
+
+static int softing_fct_cmd(struct softing *card, int16_t cmd, const char *msg)
+{
+	int ret;
+
+	ret = _softing_fct_cmd(card, cmd, 0, msg);
+	if (ret > 0) {
+		dev_alert(&card->pdev->dev, "%s returned %u\n", msg, ret);
+		ret = -EIO;
+	}
+	return ret;
+}
+
+int softing_bootloader_command(struct softing *card, int16_t cmd,
+		const char *msg)
+{
+	int ret;
+	unsigned long stamp;
+
+	iowrite16(RES_NONE, &card->dpram[DPRAM_RECEIPT]);
+	iowrite16(cmd, &card->dpram[DPRAM_COMMAND]);
+	/* be sure to flush this to the card */
+	wmb();
+	stamp = jiffies + 3 * HZ;
+	/* wait for card */
+	do {
+		ret = ioread16(&card->dpram[DPRAM_RECEIPT]);
+		/* don't have any cached variables */
+		rmb();
+		if (ret == RES_OK)
+			return 0;
+		if (time_after(jiffies, stamp))
+			break;
+		/* process context => relax */
+		usleep_range(500, 10000);
+	} while (!signal_pending(current));
+
+	ret = (ret == RES_NONE) ? -ETIMEDOUT : -ECANCELED;
+	dev_alert(&card->pdev->dev, "bootloader %s failed (%i)\n", msg, ret);
+	return ret;
+}
+
+static int fw_parse(const uint8_t **pmem, uint16_t *ptype, uint32_t *paddr,
+		uint16_t *plen, const uint8_t **pdat)
+{
+	uint16_t checksum[2];
+	const uint8_t *mem;
+	const uint8_t *end;
+
+	/*
+	 * firmware records are a binary, unaligned stream composed of:
+	 * uint16_t type;
+	 * uint32_t addr;
+	 * uint16_t len;
+	 * uint8_t dat[len];
+	 * uint16_t checksum;
+	 * all values in little endian.
+	 * We could define a struct for this, with __attribute__((packed)),
+	 * but would that solve the alignment in _all_ cases (cfr. the
+	 * struct itself may be an odd address)?
+	 *
+	 * I chose to use leXX_to_cpup() since this solves both
+	 * endianness & alignment.
+	 */
+	mem = *pmem;
+	*ptype = le16_to_cpup((void *)&mem[0]);
+	*paddr = le32_to_cpup((void *)&mem[2]);
+	*plen = le16_to_cpup((void *)&mem[6]);
+	*pdat = &mem[8];
+	/* verify checksum */
+	end = &mem[8 + *plen];
+	checksum[0] = le16_to_cpup((void *)end);
+	for (checksum[1] = 0; mem < end; ++mem)
+		checksum[1] += *mem;
+	if (checksum[0] != checksum[1])
+		return -EINVAL;
+	/* increment */
+	*pmem += 10 + *plen;
+	return 0;
+}
+
+int softing_load_fw(const char *file, struct softing *card,
+		__iomem uint8_t *dpram, unsigned int size, int offset)
+{
+	const struct firmware *fw;
+	int ret;
+	const uint8_t *mem, *end, *dat;
+	uint16_t type, len;
+	uint32_t addr;
+	uint8_t *buf = NULL;
+	int buflen = 0;
+	int8_t type_end = 0;
+
+	ret = request_firmware(&fw, file, &card->pdev->dev);
+	if (ret < 0)
+		return ret;
+	dev_dbg(&card->pdev->dev, "%s, firmware(%s) got %u bytes"
+		", offset %c0x%04x\n",
+		card->pdat->name, file, (unsigned int)fw->size,
+		(offset >= 0) ? '+' : '-', (unsigned int)abs(offset));
+	/* parse the firmware */
+	mem = fw->data;
+	end = &mem[fw->size];
+	/* look for header record */
+	ret = fw_parse(&mem, &type, &addr, &len, &dat);
+	if (ret < 0)
+		goto failed;
+	if (type != 0xffff)
+		goto failed;
+	if (strncmp("Structured Binary Format, Softing GmbH" , dat, len)) {
+		ret = -EINVAL;
+		goto failed;
+	}
+	/* ok, we had a header */
+	while (mem < end) {
+		ret = fw_parse(&mem, &type, &addr, &len, &dat);
+		if (ret < 0)
+			goto failed;
+		if (type == 3) {
+			/* start address, not used here */
+			continue;
+		} else if (type == 1) {
+			/* eof */
+			type_end = 1;
+			break;
+		} else if (type != 0) {
+			ret = -EINVAL;
+			goto failed;
+		}
+
+		if ((addr + len + offset) > size)
+			goto failed;
+		memcpy_toio(&dpram[addr + offset], dat, len);
+		/* be sure to flush caches from IO space */
+		mb();
+		if (len > buflen) {
+			/* align buflen */
+			buflen = (len + (1024-1)) & ~(1024-1);
+			buf = krealloc(buf, buflen, GFP_KERNEL);
+			if (!buf) {
+				ret = -ENOMEM;
+				goto failed;
+			}
+		}
+		/* verify record data */
+		memcpy_fromio(buf, &dpram[addr + offset], len);
+		if (memcmp(buf, dat, len)) {
+			/* is not ok */
+			dev_alert(&card->pdev->dev, "DPRAM readback failed\n");
+			ret = -EIO;
+			goto failed;
+		}
+	}
+	if (!type_end)
+		/* no end record seen */
+		goto failed;
+	ret = 0;
+failed:
+	kfree(buf);
+	release_firmware(fw);
+	if (ret < 0)
+		dev_info(&card->pdev->dev, "firmware %s failed\n", file);
+	return ret;
+}
+
+int softing_load_app_fw(const char *file, struct softing *card)
+{
+	const struct firmware *fw;
+	const uint8_t *mem, *end, *dat;
+	int ret, j;
+	uint16_t type, len;
+	uint32_t addr, start_addr = 0;
+	unsigned int sum, rx_sum;
+	int8_t type_end = 0, type_entrypoint = 0;
+
+	ret = request_firmware(&fw, file, &card->pdev->dev);
+	if (ret) {
+		dev_alert(&card->pdev->dev, "request_firmware(%s) got %i\n",
+			file, ret);
+		return ret;
+	}
+	dev_dbg(&card->pdev->dev, "firmware(%s) got %lu bytes\n",
+		file, (unsigned long)fw->size);
+	/* parse the firmware */
+	mem = fw->data;
+	end = &mem[fw->size];
+	/* look for header record */
+	ret = fw_parse(&mem, &type, &addr, &len, &dat);
+	if (ret)
+		goto failed;
+	ret = -EINVAL;
+	if (type != 0xffff) {
+		dev_alert(&card->pdev->dev, "firmware starts with type 0x%x\n",
+			type);
+		goto failed;
+	}
+	if (strncmp("Structured Binary Format, Softing GmbH", dat, len)) {
+		dev_alert(&card->pdev->dev, "firmware string '%.*s' fault\n",
+				len, dat);
+		goto failed;
+	}
+	/* ok, we had a header */
+	while (mem < end) {
+		ret = fw_parse(&mem, &type, &addr, &len, &dat);
+		if (ret)
+			goto failed;
+
+		if (type == 3) {
+			/* start address */
+			start_addr = addr;
+			type_entrypoint = 1;
+			continue;
+		} else if (type == 1) {
+			/* eof */
+			type_end = 1;
+			break;
+		} else if (type != 0) {
+			dev_alert(&card->pdev->dev,
+					"unknown record type 0x%04x\n", type);
+			ret = -EINVAL;
+			goto failed;
+		}
+
+		/* regualar data */
+		for (sum = 0, j = 0; j < len; ++j)
+			sum += dat[j];
+		/* work in 16bit (target) */
+		sum &= 0xffff;
+
+		memcpy_toio(&card->dpram[card->pdat->app.offs], dat, len);
+		iowrite32(card->pdat->app.offs + card->pdat->app.addr,
+				&card->dpram[DPRAM_COMMAND + 2]);
+		iowrite32(addr, &card->dpram[DPRAM_COMMAND + 6]);
+		iowrite16(len, &card->dpram[DPRAM_COMMAND + 10]);
+		iowrite8(1, &card->dpram[DPRAM_COMMAND + 12]);
+		ret = softing_bootloader_command(card, 1, "loading app.");
+		if (ret < 0)
+			goto failed;
+		/* verify checksum */
+		rx_sum = ioread16(&card->dpram[DPRAM_RECEIPT + 2]);
+		if (rx_sum != sum) {
+			dev_alert(&card->pdev->dev, "SRAM seems to be damaged"
+				", wanted 0x%04x, got 0x%04x\n", sum, rx_sum);
+			ret = -EIO;
+			goto failed;
+		}
+	}
+	if (!type_end || !type_entrypoint)
+		goto failed;
+	/* start application in card */
+	iowrite32(start_addr, &card->dpram[DPRAM_COMMAND + 2]);
+	iowrite8(1, &card->dpram[DPRAM_COMMAND + 6]);
+	ret = softing_bootloader_command(card, 3, "start app.");
+	if (ret < 0)
+		goto failed;
+	ret = 0;
+failed:
+	release_firmware(fw);
+	if (ret < 0)
+		dev_info(&card->pdev->dev, "firmware %s failed\n", file);
+	return ret;
+}
+
+static int softing_reset_chip(struct softing *card)
+{
+	int ret;
+
+	do {
+		/* reset chip */
+		iowrite8(0, &card->dpram[DPRAM_RESET_RX_FIFO]);
+		iowrite8(0, &card->dpram[DPRAM_RESET_RX_FIFO+1]);
+		iowrite8(1, &card->dpram[DPRAM_RESET]);
+		iowrite8(0, &card->dpram[DPRAM_RESET+1]);
+
+		ret = softing_fct_cmd(card, 0, "reset_can");
+		if (!ret)
+			break;
+		if (signal_pending(current))
+			/* don't wait any longer */
+			break;
+	} while (1);
+	card->tx.pending = 0;
+	return ret;
+}
+
+int softing_chip_poweron(struct softing *card)
+{
+	int ret;
+	/* sync */
+	ret = _softing_fct_cmd(card, 99, 0x55, "sync-a");
+	if (ret < 0)
+		goto failed;
+
+	ret = _softing_fct_cmd(card, 99, 0xaa, "sync-b");
+	if (ret < 0)
+		goto failed;
+
+	ret = softing_reset_chip(card);
+	if (ret < 0)
+		goto failed;
+	/* get_serial */
+	ret = softing_fct_cmd(card, 43, "get_serial_number");
+	if (ret < 0)
+		goto failed;
+	card->id.serial = ioread32(&card->dpram[DPRAM_FCT_PARAM]);
+	/* get_version */
+	ret = softing_fct_cmd(card, 12, "get_version");
+	if (ret < 0)
+		goto failed;
+	card->id.fw_version = ioread16(&card->dpram[DPRAM_FCT_PARAM + 2]);
+	card->id.hw_version = ioread16(&card->dpram[DPRAM_FCT_PARAM + 4]);
+	card->id.license = ioread16(&card->dpram[DPRAM_FCT_PARAM + 6]);
+	card->id.chip[0] = ioread16(&card->dpram[DPRAM_FCT_PARAM + 8]);
+	card->id.chip[1] = ioread16(&card->dpram[DPRAM_FCT_PARAM + 10]);
+	return 0;
+failed:
+	return ret;
+}
+
+static void softing_initialize_timestamp(struct softing *card)
+{
+	uint64_t ovf;
+
+	card->ts_ref = ktime_get();
+
+	/* 16MHz is the reference */
+	ovf = 0x100000000ULL * 16;
+	do_div(ovf, card->pdat->freq ?: 16);
+
+	card->ts_overflow = ktime_add_us(ktime_set(0, 0), ovf);
+}
+
+ktime_t softing_raw2ktime(struct softing *card, u32 raw)
+{
+	uint64_t rawl;
+	ktime_t now, real_offset;
+	ktime_t target;
+	ktime_t tmp;
+
+	now = ktime_get();
+	real_offset = ktime_sub(ktime_get_real(), now);
+
+	/* find nsec from card */
+	rawl = raw * 16;
+	do_div(rawl, card->pdat->freq ?: 16);
+	target = ktime_add_us(card->ts_ref, rawl);
+	/* test for overflows */
+	tmp = ktime_add(target, card->ts_overflow);
+	while (unlikely(ktime_to_ns(tmp) > ktime_to_ns(now))) {
+		card->ts_ref = ktime_add(card->ts_ref, card->ts_overflow);
+		target = tmp;
+		tmp = ktime_add(target, card->ts_overflow);
+	}
+	return ktime_add(target, real_offset);
+}
+
+static inline int softing_error_reporting(struct net_device *netdev)
+{
+	struct softing_priv *priv = netdev_priv(netdev);
+
+	return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
+		? 1 : 0;
+}
+
+int softing_startstop(struct net_device *dev, int up)
+{
+	int ret;
+	struct softing *card;
+	struct softing_priv *priv;
+	struct net_device *netdev;
+	int bus_bitmask_start;
+	int j, error_reporting;
+	struct can_frame msg;
+	const struct can_bittiming *bt;
+
+	priv = netdev_priv(dev);
+	card = priv->card;
+
+	if (!card->fw.up)
+		return -EIO;
+
+	ret = mutex_lock_interruptible(&card->fw.lock);
+	if (ret)
+		return ret;
+
+	bus_bitmask_start = 0;
+	if (dev && up)
+		/* prepare to start this bus as well */
+		bus_bitmask_start |= (1 << priv->index);
+	/* bring netdevs down */
+	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
+		netdev = card->net[j];
+		if (!netdev)
+			continue;
+		priv = netdev_priv(netdev);
+
+		if (dev != netdev)
+			netif_stop_queue(netdev);
+
+		if (netif_running(netdev)) {
+			if (dev != netdev)
+				bus_bitmask_start |= (1 << j);
+			priv->tx.pending = 0;
+			priv->tx.echo_put = 0;
+			priv->tx.echo_get = 0;
+			/*
+			 * this bus' may just have called open_candev()
+			 * which is rather stupid to call close_candev()
+			 * already
+			 * but we may come here from busoff recovery too
+			 * in which case the echo_skb _needs_ flushing too.
+			 * just be sure to call open_candev() again
+			 */
+			close_candev(netdev);
+		}
+		priv->can.state = CAN_STATE_STOPPED;
+	}
+	card->tx.pending = 0;
+
+	softing_enable_irq(card, 0);
+	ret = softing_reset_chip(card);
+	if (ret)
+		goto failed;
+	if (!bus_bitmask_start)
+		/* no busses to be brought up */
+		goto card_done;
+
+	if ((bus_bitmask_start & 1) && (bus_bitmask_start & 2)
+			&& (softing_error_reporting(card->net[0])
+				!= softing_error_reporting(card->net[1]))) {
+		dev_alert(&card->pdev->dev,
+				"err_reporting flag differs for busses\n");
+		goto invalid;
+	}
+	error_reporting = 0;
+	if (bus_bitmask_start & 1) {
+		netdev = card->net[0];
+		priv = netdev_priv(netdev);
+		error_reporting += softing_error_reporting(netdev);
+		/* init chip 1 */
+		bt = &priv->can.bittiming;
+		iowrite16(bt->brp, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		iowrite16(bt->sjw, &card->dpram[DPRAM_FCT_PARAM + 4]);
+		iowrite16(bt->phase_seg1 + bt->prop_seg,
+				&card->dpram[DPRAM_FCT_PARAM + 6]);
+		iowrite16(bt->phase_seg2, &card->dpram[DPRAM_FCT_PARAM + 8]);
+		iowrite16((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) ? 1 : 0,
+				&card->dpram[DPRAM_FCT_PARAM + 10]);
+		ret = softing_fct_cmd(card, 1, "initialize_chip[0]");
+		if (ret < 0)
+			goto failed;
+		/* set mode */
+		iowrite16(0, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		iowrite16(0, &card->dpram[DPRAM_FCT_PARAM + 4]);
+		ret = softing_fct_cmd(card, 3, "set_mode[0]");
+		if (ret < 0)
+			goto failed;
+		/* set filter */
+		/* 11bit id & mask */
+		iowrite16(0x0000, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		iowrite16(0x07ff, &card->dpram[DPRAM_FCT_PARAM + 4]);
+		/* 29bit id.lo & mask.lo & id.hi & mask.hi */
+		iowrite16(0x0000, &card->dpram[DPRAM_FCT_PARAM + 6]);
+		iowrite16(0xffff, &card->dpram[DPRAM_FCT_PARAM + 8]);
+		iowrite16(0x0000, &card->dpram[DPRAM_FCT_PARAM + 10]);
+		iowrite16(0x1fff, &card->dpram[DPRAM_FCT_PARAM + 12]);
+		ret = softing_fct_cmd(card, 7, "set_filter[0]");
+		if (ret < 0)
+			goto failed;
+		/* set output control */
+		iowrite16(priv->output, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		ret = softing_fct_cmd(card, 5, "set_output[0]");
+		if (ret < 0)
+			goto failed;
+	}
+	if (bus_bitmask_start & 2) {
+		netdev = card->net[1];
+		priv = netdev_priv(netdev);
+		error_reporting += softing_error_reporting(netdev);
+		/* init chip2 */
+		bt = &priv->can.bittiming;
+		iowrite16(bt->brp, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		iowrite16(bt->sjw, &card->dpram[DPRAM_FCT_PARAM + 4]);
+		iowrite16(bt->phase_seg1 + bt->prop_seg,
+				&card->dpram[DPRAM_FCT_PARAM + 6]);
+		iowrite16(bt->phase_seg2, &card->dpram[DPRAM_FCT_PARAM + 8]);
+		iowrite16((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) ? 1 : 0,
+				&card->dpram[DPRAM_FCT_PARAM + 10]);
+		ret = softing_fct_cmd(card, 2, "initialize_chip[1]");
+		if (ret < 0)
+			goto failed;
+		/* set mode2 */
+		iowrite16(0, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		iowrite16(0, &card->dpram[DPRAM_FCT_PARAM + 4]);
+		ret = softing_fct_cmd(card, 4, "set_mode[1]");
+		if (ret < 0)
+			goto failed;
+		/* set filter2 */
+		/* 11bit id & mask */
+		iowrite16(0x0000, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		iowrite16(0x07ff, &card->dpram[DPRAM_FCT_PARAM + 4]);
+		/* 29bit id.lo & mask.lo & id.hi & mask.hi */
+		iowrite16(0x0000, &card->dpram[DPRAM_FCT_PARAM + 6]);
+		iowrite16(0xffff, &card->dpram[DPRAM_FCT_PARAM + 8]);
+		iowrite16(0x0000, &card->dpram[DPRAM_FCT_PARAM + 10]);
+		iowrite16(0x1fff, &card->dpram[DPRAM_FCT_PARAM + 12]);
+		ret = softing_fct_cmd(card, 8, "set_filter[1]");
+		if (ret < 0)
+			goto failed;
+		/* set output control2 */
+		iowrite16(priv->output, &card->dpram[DPRAM_FCT_PARAM + 2]);
+		ret = softing_fct_cmd(card, 6, "set_output[1]");
+		if (ret < 0)
+			goto failed;
+	}
+	/* enable_error_frame */
+	/*
+	 * Error reporting is switched off at the moment since
+	 * the receiving of them is not yet 100% verified
+	 * This should be enabled sooner or later
+	 *
+	if (error_reporting) {
+		ret = softing_fct_cmd(card, 51, "enable_error_frame");
+		if (ret < 0)
+			goto failed;
+	}
+	*/
+	/* initialize interface */
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 2]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 4]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 6]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 8]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 10]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 12]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 14]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 16]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 18]);
+	iowrite16(1, &card->dpram[DPRAM_FCT_PARAM + 20]);
+	ret = softing_fct_cmd(card, 17, "initialize_interface");
+	if (ret < 0)
+		goto failed;
+	/* enable_fifo */
+	ret = softing_fct_cmd(card, 36, "enable_fifo");
+	if (ret < 0)
+		goto failed;
+	/* enable fifo tx ack */
+	ret = softing_fct_cmd(card, 13, "fifo_tx_ack[0]");
+	if (ret < 0)
+		goto failed;
+	/* enable fifo tx ack2 */
+	ret = softing_fct_cmd(card, 14, "fifo_tx_ack[1]");
+	if (ret < 0)
+		goto failed;
+	/* start_chip */
+	ret = softing_fct_cmd(card, 11, "start_chip");
+	if (ret < 0)
+		goto failed;
+	iowrite8(0, &card->dpram[DPRAM_INFO_BUSSTATE]);
+	iowrite8(0, &card->dpram[DPRAM_INFO_BUSSTATE2]);
+	if (card->pdat->generation < 2) {
+		iowrite8(0, &card->dpram[DPRAM_V2_IRQ_TOHOST]);
+		/* flush the DPRAM caches */
+		wmb();
+	}
+
+	softing_initialize_timestamp(card);
+
+	/*
+	 * do socketcan notifications/status changes
+	 * from here, no errors should occur, or the failed: part
+	 * must be reviewed
+	 */
+	memset(&msg, 0, sizeof(msg));
+	msg.can_id = CAN_ERR_FLAG | CAN_ERR_RESTARTED;
+	msg.can_dlc = CAN_ERR_DLC;
+	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
+		if (!(bus_bitmask_start & (1 << j)))
+			continue;
+		netdev = card->net[j];
+		if (!netdev)
+			continue;
+		priv = netdev_priv(netdev);
+		priv->can.state = CAN_STATE_ERROR_ACTIVE;
+		open_candev(netdev);
+		if (dev != netdev) {
+			/* notify other busses on the restart */
+			softing_netdev_rx(netdev, &msg, ktime_set(0, 0));
+			++priv->can.can_stats.restarts;
+		}
+		netif_wake_queue(netdev);
+	}
+
+	/* enable interrupts */
+	ret = softing_enable_irq(card, 1);
+	if (ret)
+		goto failed;
+card_done:
+	mutex_unlock(&card->fw.lock);
+	return 0;
+invalid:
+	ret = -EINVAL;
+failed:
+	softing_enable_irq(card, 0);
+	softing_reset_chip(card);
+	mutex_unlock(&card->fw.lock);
+	/* bring all other interfaces down */
+	for (j = 0; j < ARRAY_SIZE(card->net); ++j) {
+		netdev = card->net[j];
+		if (!netdev)
+			continue;
+		dev_close(netdev);
+	}
+	return ret;
+}
+
+int softing_default_output(struct net_device *netdev)
+{
+	struct softing_priv *priv = netdev_priv(netdev);
+	struct softing *card = priv->card;
+
+	switch (priv->chip) {
+	case 1000:
+		return (card->pdat->generation < 2) ? 0xfb : 0xfa;
+	case 5:
+		return 0x60;
+	default:
+		return 0x40;
+	}
+}