/*
* slcan.c - serial line CAN interface driver (using tty line discipline)
*
- * Copyright (c) 2007 Volkswagen Group Electronic Research
- * All rights reserved.
+ * This file is derived from linux/drivers/net/slip.c
*
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions, the following disclaimer and
- * the referenced file 'COPYING'.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of Volkswagen nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
+ * Therefore it has the same (strange?) behaviour not to unregister the
+ * netdevice when detaching the tty. Is there any better solution?
+ *
+ * Do not try to attach, detach and re-attach a tty for this reason ...
*
- * Alternatively, provided that this notice is retained in full, this
- * software may be distributed under the terms of the GNU General
- * Public License ("GPL") version 2 as distributed in the 'COPYING'
- * file from the main directory of the linux kernel source.
+ * slip.c Authors : Laurence Culhane <loz@holmes.demon.co.uk>
+ * Fred N. van Kempen <waltje@uwalt.nl.mugnet.org>
+ * slcan.c Author : Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
*
- * The provided data structures and external interfaces from this code
- * are not restricted to be used by modules with a GPL compatible license.
+ * Copyright (c) 2007-2009 Volkswagen Group Electronic Research
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * 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. You can also get it
+ * at http://www.gnu.org/licenses/gpl.html
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
*
*/
-/*
- * This file is derived from linux/drivers/net/slip.c
- *
- * Therefore it has the same (strange?) behaviour not to unregister the
- * netdevice when detaching the tty. Is there any better solution?
- *
- * Do not try to attach, detach and re-attach a tty for this reason ...
- *
- * slip.c Authors: Laurence Culhane, <loz@holmes.demon.co.uk>
- * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
- */
-
+#include <linux/version.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <asm/system.h>
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,17)
+#include <linux/uaccess.h>
+#else
#include <asm/uaccess.h>
+#endif
#include <linux/bitops.h>
+#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/init.h>
-#include <linux/can.h>
-#include <linux/can/version.h>
+#include <socketcan/can.h>
+#include <socketcan/can/version.h> /* for RCSID. Removed by mkpatch script */
RCSID("$Id$");
-static __initdata const char banner[] = KERN_INFO
- "CAN: serial line CAN interface " VERSION "\n";
+static __initdata const char banner[] =
+ KERN_INFO "slcan: serial line CAN interface driver\n";
MODULE_ALIAS_LDISC(N_SLCAN);
MODULE_DESCRIPTION("serial line CAN interface");
-MODULE_LICENSE("Dual BSD/GPL");
+MODULE_LICENSE("GPL");
MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
#ifdef CONFIG_CAN_DEBUG_DEVICES
-static int debug = 0;
+static int debug;
module_param(debug, int, S_IRUGO);
#define DBG(args...) (debug & 1 ? \
(printk(KERN_DEBUG "slcan %s: ", __func__), \
* you will have to modify two kernel includes & recompile the kernel.
*
* Add this in include/asm/termios.h after the definition of N_HCI:
- * #define N_SLCAN 16
+ * #define N_SLCAN 16
*
* Increment NR_LDICS in include/linux/tty.h from 16 to 17
*
* NEW: Since Kernel 2.6.21 you only have to change include/linux/tty.h
*
+ * HACK for precompiled Kernels:
+ *
+ * In order to use the slcan driver without rebuilding the kernel, the slcan
+ * driver must be compiled to use an existing line discipline.
+ * The N_MOUSE line discipline is documented to be free for custom use and
+ * using it *should* not cause any side effect.
+ *
+ * Then, before compiling the slcan driver, add a -DN_SLCAN=N_MOUSE
+ * compilation option in its Makefile. The slcan_attach tool must(!!) also be
+ * rebuild to use the right value for N_SLCAN. This workaround will allow
+ * to use the slcan driver with an existing kernel.
*/
-#define SLC_CHECK_TRANSMIT
#define SLCAN_MAGIC 0x53CA
static int maxdev = 10; /* MAX number of SLCAN channels;
unsigned char *xhead; /* pointer to next XMIT byte */
int xleft; /* bytes left in XMIT queue */
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
/* SLCAN interface statistics. */
struct net_device_stats stats;
+#endif
unsigned long flags; /* Flag values/ mode etc */
#define SLF_INUSE 0 /* Channel in use */
static struct net_device **slcan_devs;
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+/* Netdevice get statistics request */
+static struct net_device_stats *slc_get_stats(struct net_device *dev)
+{
+ struct slcan *sl = netdev_priv(dev);
+
+ return &sl->stats;
+}
+#endif
+
/************************************************************************
* SLCAN ENCAPSULATION FORMAT *
************************************************************************/
* The <id> is 3 (standard) or 8 (extended) bytes in ASCII Hex (base64).
* The <dlc> is a one byte ASCII number ('0' - '8')
* The <data> section has at much ASCII Hex bytes as defined by the <dlc>
- *
+ *
* Examples:
*
* t1230 : can_id 0x123, can_dlc 0, no data
* STANDARD SLCAN DECAPSULATION *
************************************************************************/
-static int asc2nibble(char c) {
+static int asc2nibble(char c)
+{
if ((c >= '0') && (c <= '9'))
return c - '0';
/* Send one completely decapsulated can_frame to the network layer */
static void slc_bump(struct slcan *sl)
{
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+ struct net_device_stats *stats = slc_get_stats(sl->dev);
+#else
+ struct net_device_stats *stats = &sl->dev->stats;
+#endif
struct sk_buff *skb;
struct can_frame cf;
int i, dlc_pos, tmp;
+ unsigned long ultmp;
char cmd = sl->rbuff[0];
if ((cmd != 't') && (cmd != 'T') && (cmd != 'r') && (cmd != 'R'))
if (!((sl->rbuff[dlc_pos] >= '0') && (sl->rbuff[dlc_pos] < '9')))
return;
- cf.can_dlc = sl->rbuff[dlc_pos] & 0x0F; /* get can_dlc */
+ cf.can_dlc = sl->rbuff[dlc_pos] - '0'; /* get can_dlc from ASCII val */
sl->rbuff[dlc_pos] = 0; /* terminate can_id string */
- cf.can_id = simple_strtoul(sl->rbuff+1, NULL, 16);
-
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
+ ultmp = simple_strtoul(sl->rbuff+1, NULL, 16);
+#else
+ if (strict_strtoul(sl->rbuff+1, 16, &ultmp))
+ return;
+#endif
+ cf.can_id = ultmp;
+
if (!(cmd & 0x20)) /* NO tiny chars => extended frame format */
cf.can_id |= CAN_EFF_FLAG;
*(u64 *) (&cf.data) = 0; /* clear payload */
- for (i = 0, dlc_pos++; i < cf.can_dlc; i++){
-
- if ((tmp = asc2nibble(sl->rbuff[dlc_pos++])) > 0x0F)
+ for (i = 0, dlc_pos++; i < cf.can_dlc; i++) {
+
+ tmp = asc2nibble(sl->rbuff[dlc_pos++]);
+ if (tmp > 0x0F)
return;
cf.data[i] = (tmp << 4);
- if ((tmp = asc2nibble(sl->rbuff[dlc_pos++])) > 0x0F)
+ tmp = asc2nibble(sl->rbuff[dlc_pos++]);
+ if (tmp > 0x0F)
return;
cf.data[i] |= tmp;
}
skb->dev = sl->dev;
skb->protocol = htons(ETH_P_CAN);
+ skb->pkt_type = PACKET_BROADCAST;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
memcpy(skb_put(skb, sizeof(struct can_frame)),
&cf, sizeof(struct can_frame));
netif_rx(skb);
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
sl->dev->last_rx = jiffies;
- sl->stats.rx_packets++;
- sl->stats.rx_bytes += cf.can_dlc;
+#endif
+ stats->rx_packets++;
+ stats->rx_bytes += cf.can_dlc;
}
/* parse tty input stream */
static void slcan_unesc(struct slcan *sl, unsigned char s)
{
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+ struct net_device_stats *stats = slc_get_stats(sl->dev);
+#else
+ struct net_device_stats *stats = &sl->dev->stats;
+#endif
+
if ((s == '\r') || (s == '\a')) { /* CR or BEL ends the pdu */
if (!test_and_clear_bit(SLF_ERROR, &sl->flags) &&
(sl->rcount > 4)) {
sl->rbuff[sl->rcount++] = s;
return;
} else {
- sl->stats.rx_over_errors++;
+ stats->rx_over_errors++;
set_bit(SLF_ERROR, &sl->flags);
}
}
/* Encapsulate one can_frame and stuff into a TTY queue. */
static void slc_encaps(struct slcan *sl, struct can_frame *cf)
{
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+ struct net_device_stats *stats = slc_get_stats(sl->dev);
+#else
+ struct net_device_stats *stats = &sl->dev->stats;
+#endif
int actual, idx, i;
char cmd;
* 14 Oct 1994 Dmitry Gorodchanin.
*/
sl->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,26)
actual = sl->tty->driver->write(sl->tty, sl->xbuff, strlen(sl->xbuff));
-#ifdef SLC_CHECK_TRANSMIT
- sl->dev->trans_start = jiffies;
+#else
+ actual = sl->tty->ops->write(sl->tty, sl->xbuff, strlen(sl->xbuff));
#endif
sl->xleft = strlen(sl->xbuff) - actual;
sl->xhead = sl->xbuff + actual;
- sl->stats.tx_bytes += cf->can_dlc;
+ stats->tx_bytes += cf->can_dlc;
}
/*
{
int actual;
struct slcan *sl = (struct slcan *) tty->disc_data;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+ struct net_device_stats *stats = slc_get_stats(sl->dev);
+#else
+ struct net_device_stats *stats = &sl->dev->stats;
+#endif
/* First make sure we're connected. */
- if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev)) {
+ if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev))
return;
- }
+
if (sl->xleft <= 0) {
/* Now serial buffer is almost free & we can start
* transmission of another packet */
- sl->stats.tx_packets++;
+ stats->tx_packets++;
tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
netif_wake_queue(sl->dev);
return;
}
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,26)
actual = tty->driver->write(tty, sl->xhead, sl->xleft);
+#else
+ actual = tty->ops->write(tty, sl->xhead, sl->xleft);
+#endif
sl->xleft -= actual;
sl->xhead += actual;
}
-static void slc_tx_timeout(struct net_device *dev)
-{
- struct slcan *sl = netdev_priv(dev);
-
- spin_lock(&sl->lock);
-
- if (netif_queue_stopped(dev)) {
- if (!netif_running(dev))
- goto out;
-
- /* May be we must check transmitter timeout here ?
- * 14 Oct 1994 Dmitry Gorodchanin.
- */
-#ifdef SLC_CHECK_TRANSMIT
- if (time_before(jiffies, dev->trans_start + 20 * HZ)) {
- /* 20 sec timeout not reached */
- goto out;
- }
- printk(KERN_WARNING "%s: transmit timed out, %s?\n", dev->name,
- (sl->tty->driver->chars_in_buffer(sl->tty) || sl->xleft)
- ? "bad line quality" : "driver error");
- sl->xleft = 0;
- sl->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
- netif_wake_queue(sl->dev);
-#endif
- }
-out:
- spin_unlock(&sl->lock);
-}
-
/******************************************
* Routines looking at netdevice side.
******************************************/
/* Send a can_frame to a TTY queue. */
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
static int slc_xmit(struct sk_buff *skb, struct net_device *dev)
+#else
+static netdev_tx_t slc_xmit(struct sk_buff *skb, struct net_device *dev)
+#endif
{
struct slcan *sl = netdev_priv(dev);
spin_unlock(&sl->lock);
out:
- dev_kfree_skb(skb);
+ kfree_skb(skb);
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
return 0;
+#else
+ return NETDEV_TX_OK;
+#endif
}
{
struct slcan *sl = netdev_priv(dev);
- if (sl->tty==NULL)
+ if (sl->tty == NULL)
return -ENODEV;
sl->flags &= (1 << SLF_INUSE);
return 0;
}
-/* Netdevice get statistics request */
-static struct net_device_stats *slc_get_stats(struct net_device *dev)
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,31)
+/* Hook the destructor so we can free slcan devs at the right point in time */
+static void slc_free_netdev(struct net_device *dev)
{
- struct slcan *sl = netdev_priv(dev);
-
- return (&sl->stats);
+ int i = dev->base_addr;
+ free_netdev(dev);
+ slcan_devs[i] = NULL;
}
+#endif
+
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
+static const struct net_device_ops slc_netdev_ops = {
+ .ndo_open = slc_open,
+ .ndo_stop = slc_close,
+ .ndo_start_xmit = slc_xmit,
+};
+#endif
/* Netdevice register callback */
static void slc_setup(struct net_device *dev)
{
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,28)
+ dev->netdev_ops = &slc_netdev_ops;
+#else
dev->open = slc_open;
- dev->destructor = free_netdev;
dev->stop = slc_close;
- dev->get_stats = slc_get_stats;
dev->hard_start_xmit = slc_xmit;
+#endif
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,31)
+ dev->destructor = slc_free_netdev;
+#else
+ dev->destructor = free_netdev;
+#endif
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+ dev->get_stats = slc_get_stats;
+#endif
dev->hard_header_len = 0;
dev->addr_len = 0;
dev->tx_queue_len = 10;
- SET_MODULE_OWNER(dev);
-
dev->mtu = sizeof(struct can_frame);
dev->type = ARPHRD_CAN;
-#ifdef SLC_CHECK_TRANSMIT
- dev->tx_timeout = slc_tx_timeout;
- dev->watchdog_timeo = 20*HZ;
-#endif
/* New-style flags. */
dev->flags = IFF_NOARP;
* Routines looking at TTY side.
******************************************/
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
-#else
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,16)
static int slcan_receive_room(struct tty_struct *tty)
{
return 65536; /* We can handle an infinite amount of data. :-) */
}
#endif
+
/*
* Handle the 'receiver data ready' interrupt.
* This function is called by the 'tty_io' module in the kernel when
const unsigned char *cp, char *fp, int count)
{
struct slcan *sl = (struct slcan *) tty->disc_data;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
+ struct net_device_stats *stats = slc_get_stats(sl->dev);
+#else
+ struct net_device_stats *stats = &sl->dev->stats;
+#endif
if (!sl || sl->magic != SLCAN_MAGIC ||
!netif_running(sl->dev))
/* Read the characters out of the buffer */
while (count--) {
if (fp && *fp++) {
- if (!test_and_set_bit(SLF_ERROR, &sl->flags)) {
- sl->stats.rx_errors++;
- }
+ if (!test_and_set_bit(SLF_ERROR, &sl->flags))
+ stats->rx_errors++;
cp++;
continue;
}
struct slcan *sl;
for (i = 0; i < maxdev; i++) {
- if ((dev = slcan_devs[i]) == NULL)
+ dev = slcan_devs[i];
+ if (dev == NULL)
break;
sl = netdev_priv(dev);
static struct slcan *slc_alloc(dev_t line)
{
int i;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
int sel = -1;
int score = -1;
+#endif
struct net_device *dev = NULL;
struct slcan *sl;
if (dev == NULL)
break;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
sl = netdev_priv(dev);
if (sl->leased) {
if (sl->line != line)
sl->flags &= (1 << SLF_INUSE);
return sl;
}
+#endif
}
/* Sorry, too many, all slots in use */
sl = netdev_priv(dev);
if (test_bit(SLF_INUSE, &sl->flags)) {
unregister_netdevice(dev);
- free_netdev(dev); /* new in slcan.c */
dev = NULL;
slcan_devs[i] = NULL;
}
if (!dev) {
char name[IFNAMSIZ];
- sprintf(name, "slc%d", i);
+ sprintf(name, "can%d", i);
dev = alloc_netdev(sizeof(*sl), name, slc_setup);
if (!dev)
struct slcan *sl;
int err;
- if(!capable(CAP_NET_ADMIN))
+ if (!capable(CAP_NET_ADMIN))
return -EPERM;
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,25)
+ if (tty->ops->write == NULL)
+ return -EOPNOTSUPP;
+#endif
+
/* RTnetlink lock is misused here to serialize concurrent
opens of slcan channels. There are better ways, but it is
the simplest one.
/* OK. Find a free SLCAN channel to use. */
err = -ENFILE;
- if ((sl = slc_alloc(tty_devnum(tty))) == NULL)
+ sl = slc_alloc(tty_devnum(tty));
+ if (sl == NULL)
goto err_exit;
sl->tty = tty;
sl->line = tty_devnum(tty);
sl->pid = current->pid;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
-#else
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,16)
/* FIXME: already done before we were called - seems this can go */
if (tty->driver->flush_buffer)
tty->driver->flush_buffer(tty);
#endif
+
if (!test_bit(SLF_INUSE, &sl->flags)) {
/* Perform the low-level SLCAN initialization. */
sl->rcount = 0;
set_bit(SLF_INUSE, &sl->flags);
- if ((err = register_netdevice(sl->dev)))
+ err = register_netdevice(sl->dev);
+ if (err)
goto err_free_chan;
}
/* Done. We have linked the TTY line to a channel. */
rtnl_unlock();
+
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
tty->receive_room = 65536; /* We don't flow control */
#endif
+
return sl->dev->base_addr;
err_free_chan:
return err;
}
-/*
-
- FIXME: 1,2 are fixed 3 was never true anyway.
-
- Let me to blame a bit.
- 1. TTY module calls this funstion on soft interrupt.
- 2. TTY module calls this function WITH MASKED INTERRUPTS!
- 3. TTY module does not notify us about line discipline
- shutdown,
-
- Seems, now it is clean. The solution is to consider netdevice and
- line discipline sides as two independent threads.
-
- By-product (not desired): slc? does not feel hangups and remains open.
- It is supposed, that user level program (dip, diald, slattach...)
- will catch SIGHUP and make the rest of work.
-
- I see no way to make more with current tty code. --ANK
- */
-
/*
* Close down a SLCAN channel.
* This means flushing out any pending queues, and then returning. This
* call is serialized against other ldisc functions.
+ *
+ * We also use this method for a hangup event.
*/
static void slcan_close(struct tty_struct *tty)
{
if (!sl->leased)
sl->line = 0;
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,31)
+ /* Flush network side */
+ unregister_netdev(sl->dev);
+ /* This will complete via sl_free_netdev */
+#else
/* Count references from TTY module */
+#endif
}
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,31)
+static int slcan_hangup(struct tty_struct *tty)
+{
+ slcan_close(tty);
+ return 0;
+}
+#endif
+
/* Perform I/O control on an active SLCAN channel. */
static int slcan_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
unsigned int tmp;
/* First make sure we're connected. */
- if (!sl || sl->magic != SLCAN_MAGIC) {
+ if (!sl || sl->magic != SLCAN_MAGIC)
return -EINVAL;
- }
- switch(cmd) {
+ switch (cmd) {
case SIOCGIFNAME:
tmp = strlen(sl->dev->name) + 1;
if (copy_to_user((void __user *)arg, sl->dev->name, tmp))
case SIOCSIFHWADDR:
return -EINVAL;
-
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27)
/* Allow stty to read, but not set, the serial port */
case TCGETS:
case TCGETA:
default:
return -ENOIOCTLCMD;
+#else
+ default:
+ return tty_mode_ioctl(tty, file, cmd, arg);
+#endif
}
}
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27)
static struct tty_ldisc slc_ldisc = {
+#else
+static struct tty_ldisc_ops slc_ldisc = {
+#endif
.owner = THIS_MODULE,
.magic = TTY_LDISC_MAGIC,
.name = "slcan",
.open = slcan_open,
.close = slcan_close,
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,31)
+ .hangup = slcan_hangup,
+#endif
.ioctl = slcan_ioctl,
.receive_buf = slcan_receive_buf,
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
-#else
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,16)
.receive_room = slcan_receive_room,
#endif
.write_wakeup = slcan_write_wakeup,
maxdev = 4; /* Sanity */
printk(banner);
- printk(KERN_INFO "slcan: %d dynamic interface channels.\n", maxdev );
+ printk(KERN_INFO "slcan: %d dynamic interface channels.\n", maxdev);
slcan_devs = kmalloc(sizeof(struct net_device *)*maxdev, GFP_KERNEL);
if (!slcan_devs) {
memset(slcan_devs, 0, sizeof(struct net_device *)*maxdev);
/* Fill in our line protocol discipline, and register it */
- if ((status = tty_register_ldisc(N_SLCAN, &slc_ldisc)) != 0) {
+ status = tty_register_ldisc(N_SLCAN, &slc_ldisc);
+ if (status != 0) {
printk(KERN_ERR "slcan: can't register line discipline\n");
kfree(slcan_devs);
}
}
} while (busy && time_before(jiffies, timeout));
+ /* FIXME (2.6.32+): hangup is async so we should wait when doing
+ this second phase */
for (i = 0; i < maxdev; i++) {
dev = slcan_devs[i];
kfree(slcan_devs);
slcan_devs = NULL;
- if ((i = tty_unregister_ldisc(N_SLCAN)))
- {
+ i = tty_unregister_ldisc(N_SLCAN);
+ if (i)
printk(KERN_ERR "slcan: can't unregister ldisc (err %d)\n", i);
- }
}
module_init(slcan_init);