Commit 2bb0a0bb authored by Ralf Bächle's avatar Ralf Bächle Committed by Jeff Garzik

[hamradio 6pack] cleanup

parent f2710107
...@@ -3,15 +3,13 @@ ...@@ -3,15 +3,13 @@
* devices like TTY. It interfaces between a raw TTY and the * devices like TTY. It interfaces between a raw TTY and the
* kernel's AX.25 protocol layers. * kernel's AX.25 protocol layers.
* *
* Version: @(#)6pack.c 0.3.0 04/07/98
*
* Authors: Andreas Knsgen <ajk@iehk.rwth-aachen.de> * Authors: Andreas Knsgen <ajk@iehk.rwth-aachen.de>
* Ralf Baechle DO1GRB <ralf@linux-mips.org>
* *
* Quite a lot of stuff "stolen" by Jrg Reuter from slip.c, written by * Quite a lot of stuff "stolen" by Joerg Reuter from slip.c, written by
* *
* Laurence Culhane, <loz@holmes.demon.co.uk> * Laurence Culhane, <loz@holmes.demon.co.uk>
* Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org> * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
*
*/ */
#include <linux/config.h> #include <linux/config.h>
...@@ -31,20 +29,23 @@ ...@@ -31,20 +29,23 @@
#include <linux/etherdevice.h> #include <linux/etherdevice.h>
#include <linux/skbuff.h> #include <linux/skbuff.h>
#include <linux/rtnetlink.h> #include <linux/rtnetlink.h>
#include <linux/spinlock.h>
#include <linux/if_arp.h> #include <linux/if_arp.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/ip.h> #include <linux/ip.h>
#include <linux/tcp.h> #include <linux/tcp.h>
#include <asm/semaphore.h>
#include <asm/atomic.h>
#define SIXPACK_VERSION "Revision: 0.3.0" #define SIXPACK_VERSION "Revision: 0.3.0"
/* sixpack priority commands */ /* sixpack priority commands */
#define SIXP_SEOF 0x40 /* start and end of a 6pack frame */ #define SIXP_SEOF 0x40 /* start and end of a 6pack frame */
#define SIXP_TX_URUN 0x48 /* transmit overrun */ #define SIXP_TX_URUN 0x48 /* transmit overrun */
#define SIXP_RX_ORUN 0x50 /* receive overrun */ #define SIXP_RX_ORUN 0x50 /* receive overrun */
#define SIXP_RX_BUF_OVL 0x58 /* receive buffer overflow */ #define SIXP_RX_BUF_OVL 0x58 /* receive buffer overflow */
#define SIXP_CHKSUM 0xFF /* valid checksum of a 6pack frame */ #define SIXP_CHKSUM 0xFF /* valid checksum of a 6pack frame */
/* masks to get certain bits out of the status bytes sent by the TNC */ /* masks to get certain bits out of the status bytes sent by the TNC */
...@@ -78,23 +79,20 @@ ...@@ -78,23 +79,20 @@
#define SIXP_MTU 256 /* Default MTU */ #define SIXP_MTU 256 /* Default MTU */
enum sixpack_flags { enum sixpack_flags {
SIXPF_INUSE, /* Channel in use */
SIXPF_ERROR, /* Parity, etc. error */ SIXPF_ERROR, /* Parity, etc. error */
}; };
struct sixpack { struct sixpack {
int magic;
/* Various fields. */ /* Various fields. */
struct tty_struct *tty; /* ptr to TTY structure */ struct tty_struct *tty; /* ptr to TTY structure */
struct net_device *dev; /* easy for intr handling */ struct net_device *dev; /* easy for intr handling */
/* These are pointers to the malloc()ed frame buffers. */ /* These are pointers to the malloc()ed frame buffers. */
unsigned char *rbuff; /* receiver buffer */ unsigned char *rbuff; /* receiver buffer */
int rcount; /* received chars counter */ int rcount; /* received chars counter */
unsigned char *xbuff; /* transmitter buffer */ unsigned char *xbuff; /* transmitter buffer */
unsigned char *xhead; /* pointer to next byte to XMIT */ unsigned char *xhead; /* next byte to XMIT */
int xleft; /* bytes left in XMIT queue */ int xleft; /* bytes left in XMIT queue */
unsigned char raw_buf[4]; unsigned char raw_buf[4];
unsigned char cooked_buf[400]; unsigned char cooked_buf[400];
...@@ -105,11 +103,11 @@ struct sixpack { ...@@ -105,11 +103,11 @@ struct sixpack {
/* 6pack interface statistics. */ /* 6pack interface statistics. */
struct net_device_stats stats; struct net_device_stats stats;
int mtu; /* Our mtu (to spot changes!) */ int mtu; /* Our mtu (to spot changes!) */
int buffsize; /* Max buffers sizes */ int buffsize; /* Max buffers sizes */
unsigned long flags; /* Flag values/ mode etc */ unsigned long flags; /* Flag values/ mode etc */
unsigned char mode; /* 6pack mode */ unsigned char mode; /* 6pack mode */
/* 6pack stuff */ /* 6pack stuff */
unsigned char tx_delay; unsigned char tx_delay;
...@@ -125,112 +123,293 @@ struct sixpack { ...@@ -125,112 +123,293 @@ struct sixpack {
struct timer_list tx_t; struct timer_list tx_t;
struct timer_list resync_t; struct timer_list resync_t;
atomic_t refcnt;
struct semaphore dead_sem;
spinlock_t lock;
}; };
#define AX25_6PACK_HEADER_LEN 0 #define AX25_6PACK_HEADER_LEN 0
#define SIXPACK_MAGIC 0x5304
typedef struct sixpack_ctrl {
struct sixpack ctrl; /* 6pack things */
struct net_device dev; /* the device */
} sixpack_ctrl_t;
static sixpack_ctrl_t **sixpack_ctrls;
int sixpack_maxdev = SIXP_NRUNIT; /* Can be overridden with insmod! */
MODULE_PARM(sixpack_maxdev, "i");
MODULE_PARM_DESC(sixpack_maxdev, "number of 6PACK devices");
static void sp_start_tx_timer(struct sixpack *); static void sp_start_tx_timer(struct sixpack *);
static void sp_xmit_on_air(unsigned long);
static void resync_tnc(unsigned long);
static void sixpack_decode(struct sixpack *, unsigned char[], int); static void sixpack_decode(struct sixpack *, unsigned char[], int);
static int encode_sixpack(unsigned char *, unsigned char *, int, unsigned char); static int encode_sixpack(unsigned char *, unsigned char *, int, unsigned char);
static int sixpack_init(struct net_device *dev); static int sixpack_init(struct net_device *dev);
static void decode_prio_command(unsigned char, struct sixpack *); /*
static void decode_std_command(unsigned char, struct sixpack *); * perform the persistence/slottime algorithm for CSMA access. If the
static void decode_data(unsigned char, struct sixpack *); * persistence check was successful, write the data to the serial driver.
* Note that in case of DAMA operation, the data is not sent here.
*/
static int tnc_init(struct sixpack *); static void sp_xmit_on_air(unsigned long channel)
{
struct sixpack *sp = (struct sixpack *) channel;
int actual;
static unsigned char random;
/* Find a free 6pack channel, and link in this `tty' line. */ random = random * 17 + 41;
static inline struct sixpack *sp_alloc(void)
if (((sp->status1 & SIXP_DCD_MASK) == 0) && (random < sp->persistence)) {
sp->led_state = 0x70;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->tx_enable = 1;
actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, sp->status2);
sp->xleft -= actual;
sp->xhead += actual;
sp->led_state = 0x60;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->status2 = 0;
} else
sp_start_tx_timer(sp);
}
/* ----> 6pack timer interrupt handler and friends. <---- */
static void sp_start_tx_timer(struct sixpack *sp)
{ {
sixpack_ctrl_t *spp = NULL; int when = sp->slottime;
int i;
for (i = 0; i < sixpack_maxdev; i++) { del_timer(&sp->tx_t);
spp = sixpack_ctrls[i]; sp->tx_t.data = (unsigned long) sp;
sp->tx_t.function = sp_xmit_on_air;
sp->tx_t.expires = jiffies + ((when + 1) * HZ) / 100;
add_timer(&sp->tx_t);
}
if (spp == NULL) /* Encapsulate one AX.25 frame and stuff into a TTY queue. */
break; static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len)
{
unsigned char *msg, *p = icp;
int actual, count;
if (!test_and_set_bit(SIXPF_INUSE, &spp->ctrl.flags)) if (len > sp->mtu) { /* sp->mtu = AX25_MTU = max. PACLEN = 256 */
break; msg = "oversized transmit packet!";
goto out_drop;
} }
/* Too many devices... */ if (p[0] > 5) {
if (i >= sixpack_maxdev) msg = "invalid KISS command";
return NULL; goto out_drop;
}
/* If no channels are available, allocate one */ if ((p[0] != 0) && (len > 2)) {
if (!spp && msg = "KISS control packet too long";
(sixpack_ctrls[i] = (sixpack_ctrl_t *)kmalloc(sizeof(sixpack_ctrl_t), goto out_drop;
GFP_KERNEL)) != NULL) {
spp = sixpack_ctrls[i];
} }
memset(spp, 0, sizeof(sixpack_ctrl_t));
if ((p[0] == 0) && (len < 15)) {
/* Initialize channel control data */ msg = "bad AX.25 packet to transmit";
set_bit(SIXPF_INUSE, &spp->ctrl.flags); goto out_drop;
spp->ctrl.tty = NULL;
sprintf(spp->dev.name, "sp%d", i);
spp->dev.base_addr = i;
spp->dev.priv = (void *) &spp->ctrl;
spp->dev.next = NULL;
spp->dev.init = sixpack_init;
if (spp != NULL) {
/* register device so that it can be ifconfig'ed */
/* sixpack_init() will be called as a side-effect */
/* SIDE-EFFECT WARNING: sixpack_init() CLEARS spp->ctrl ! */
if (register_netdev(&spp->dev) == 0) {
set_bit(SIXPF_INUSE, &spp->ctrl.flags);
spp->ctrl.dev = &spp->dev;
spp->dev.priv = (void *) &spp->ctrl;
SET_MODULE_OWNER(&spp->dev);
return &spp->ctrl;
} else {
clear_bit(SIXPF_INUSE, &spp->ctrl.flags);
printk(KERN_WARNING "sp_alloc() - register_netdev() failure.\n");
}
} }
return NULL; count = encode_sixpack(p, sp->xbuff, len, sp->tx_delay);
set_bit(TTY_DO_WRITE_WAKEUP, &sp->tty->flags);
switch (p[0]) {
case 1: sp->tx_delay = p[1];
return;
case 2: sp->persistence = p[1];
return;
case 3: sp->slottime = p[1];
return;
case 4: /* ignored */
return;
case 5: sp->duplex = p[1];
return;
}
if (p[0] != 0)
return;
/*
* In case of fullduplex or DAMA operation, we don't take care about the
* state of the DCD or of any timers, as the determination of the
* correct time to send is the job of the AX.25 layer. We send
* immediately after data has arrived.
*/
if (sp->duplex == 1) {
sp->led_state = 0x70;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->tx_enable = 1;
actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, count);
sp->xleft = count - actual;
sp->xhead = sp->xbuff + actual;
sp->led_state = 0x60;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
} else {
sp->xleft = count;
sp->xhead = sp->xbuff;
sp->status2 = count;
if (sp->duplex == 0)
sp_start_tx_timer(sp);
}
return;
out_drop:
sp->stats.tx_dropped++;
netif_start_queue(sp->dev);
printk(KERN_DEBUG "%s: %s - dropped.\n", sp->dev->name, msg);
return;
}
/* Encapsulate an IP datagram and kick it into a TTY queue. */
static int sp_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct sixpack *sp = netdev_priv(dev);
spin_lock_bh(&sp->lock);
/* We were not busy, so we are now... :-) */
netif_stop_queue(dev);
sp->stats.tx_bytes += skb->len;
sp_encaps(sp, skb->data, skb->len);
spin_unlock_bh(&sp->lock);
dev_kfree_skb(skb);
return 0;
}
static int sp_open_dev(struct net_device *dev)
{
struct sixpack *sp = netdev_priv(dev);
if (sp->tty == NULL)
return -ENODEV;
return 0;
} }
/* Close the low-level part of the 6pack channel. */
static int sp_close(struct net_device *dev)
{
struct sixpack *sp = netdev_priv(dev);
spin_lock_bh(&sp->lock);
if (sp->tty) {
/* TTY discipline is running. */
clear_bit(TTY_DO_WRITE_WAKEUP, &sp->tty->flags);
}
netif_stop_queue(dev);
spin_unlock_bh(&sp->lock);
return 0;
}
/* Return the frame type ID */
static int sp_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type, void *daddr, void *saddr, unsigned len)
{
#ifdef CONFIG_INET
if (type != htons(ETH_P_AX25))
return ax25_encapsulate(skb, dev, type, daddr, saddr, len);
#endif
return 0;
}
static struct net_device_stats *sp_get_stats(struct net_device *dev)
{
struct sixpack *sp = netdev_priv(dev);
return &sp->stats;
}
static int sp_set_dev_mac_address(struct net_device *dev, void *addr)
{
struct sockaddr *sa = addr;
memcpy(dev->dev_addr, sa->sa_data, AX25_ADDR_LEN);
return 0;
}
static int sp_rebuild_header(struct sk_buff *skb)
{
#ifdef CONFIG_INET
return ax25_rebuild_header(skb);
#else
return 0;
#endif
}
static void sp_setup(struct net_device *dev)
{
static char ax25_bcast[AX25_ADDR_LEN] =
{'Q'<<1,'S'<<1,'T'<<1,' '<<1,' '<<1,' '<<1,'0'<<1};
static char ax25_test[AX25_ADDR_LEN] =
{'L'<<1,'I'<<1,'N'<<1,'U'<<1,'X'<<1,' '<<1,'1'<<1};
/* Finish setting up the DEVICE info. */
dev->init = sixpack_init;
dev->mtu = SIXP_MTU;
dev->hard_start_xmit = sp_xmit;
dev->open = sp_open_dev;
dev->destructor = free_netdev;
dev->stop = sp_close;
dev->hard_header = sp_header;
dev->get_stats = sp_get_stats;
dev->set_mac_address = sp_set_dev_mac_address;
dev->hard_header_len = AX25_MAX_HEADER_LEN;
dev->addr_len = AX25_ADDR_LEN;
dev->type = ARPHRD_AX25;
dev->tx_queue_len = 10;
dev->rebuild_header = sp_rebuild_header;
dev->tx_timeout = NULL;
/* Only activated in AX.25 mode */
memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN);
memcpy(dev->dev_addr, ax25_test, AX25_ADDR_LEN);
SET_MODULE_OWNER(dev);
/* New-style flags. */
dev->flags = 0;
}
/* Find a free 6pack channel, and link in this `tty' line. */
static inline struct sixpack *sp_alloc(void)
{
struct sixpack *sp = NULL;
struct net_device *dev = NULL;
dev = alloc_netdev(sizeof(struct sixpack), "sp%d", sp_setup);
if (!dev)
return NULL;
sp = netdev_priv(dev);
sp->dev = dev;
spin_lock_init(&sp->lock);
if (register_netdev(dev))
goto out_free;
return sp;
out_free:
printk(KERN_WARNING "sp_alloc() - register_netdev() failure.\n");
free_netdev(dev);
return NULL;
}
/* Free a 6pack channel. */ /* Free a 6pack channel. */
static inline void sp_free(struct sixpack *sp) static inline void sp_free(struct sixpack *sp)
{ {
void * tmp;
/* Free all 6pack frame buffers. */ /* Free all 6pack frame buffers. */
if (sp->rbuff) if ((tmp = xchg(&sp->rbuff, NULL)) != NULL)
kfree(sp->rbuff); kfree(tmp);
sp->rbuff = NULL; if ((tmp = xchg(&sp->xbuff, NULL)) != NULL)
if (sp->xbuff) kfree(tmp);
kfree(sp->xbuff);
sp->xbuff = NULL;
if (!test_and_clear_bit(SIXPF_INUSE, &sp->flags))
printk(KERN_WARNING "%s: sp_free for already free unit.\n", sp->dev->name);
} }
/* Send one completely decapsulated IP datagram to the IP layer. */ /* Send one completely decapsulated IP datagram to the IP layer. */
/* This is the routine that sends the received data to the kernel AX.25. /*
'cmd' is the KISS command. For AX.25 data, it is zero. */ * This is the routine that sends the received data to the kernel AX.25.
* 'cmd' is the KISS command. For AX.25 data, it is zero.
*/
static void sp_bump(struct sixpack *sp, char cmd) static void sp_bump(struct sixpack *sp, char cmd)
{ {
...@@ -238,98 +417,60 @@ static void sp_bump(struct sixpack *sp, char cmd) ...@@ -238,98 +417,60 @@ static void sp_bump(struct sixpack *sp, char cmd)
int count; int count;
unsigned char *ptr; unsigned char *ptr;
count = sp->rcount+1; count = sp->rcount + 1;
sp->stats.rx_bytes += count; sp->stats.rx_bytes += count;
if ((skb = dev_alloc_skb(count)) == NULL) { if ((skb = dev_alloc_skb(count)) == NULL)
printk(KERN_DEBUG "%s: memory squeeze, dropping packet.\n", sp->dev->name); goto out_mem;
sp->stats.rx_dropped++;
return;
}
skb->dev = sp->dev; skb->dev = sp->dev;
ptr = skb_put(skb, count); ptr = skb_put(skb, count);
*ptr++ = cmd; /* KISS command */ *ptr++ = cmd; /* KISS command */
memcpy(ptr, (sp->cooked_buf)+1, count); memcpy(ptr, sp->cooked_buf + 1, count);
skb->mac.raw = skb->data; skb->mac.raw = skb->data;
skb->protocol = htons(ETH_P_AX25); skb->protocol = htons(ETH_P_AX25);
netif_rx(skb); netif_rx(skb);
sp->dev->last_rx = jiffies; sp->dev->last_rx = jiffies;
sp->stats.rx_packets++; sp->stats.rx_packets++;
return;
out_mem:
sp->stats.rx_dropped++;
} }
/* ----------------------------------------------------------------------- */ /* ----------------------------------------------------------------------- */
/* Encapsulate one AX.25 frame and stuff into a TTY queue. */ /*
static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len) * We have a potential race on dereferencing tty->disc_data, because the tty
* layer provides no locking at all - thus one cpu could be running
* sixpack_receive_buf while another calls sixpack_close, which zeroes
* tty->disc_data and frees the memory that sixpack_receive_buf is using. The
* best way to fix this is to use a rwlock in the tty struct, but for now we
* use a single global rwlock for all ttys in ppp line discipline.
*/
static rwlock_t disc_data_lock = RW_LOCK_UNLOCKED;
static struct sixpack *sp_get(struct tty_struct *tty)
{ {
unsigned char *p; struct sixpack *sp;
int actual, count;
if (len > sp->mtu) { /* sp->mtu = AX25_MTU = max. PACLEN = 256 */
printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n", sp->dev->name);
sp->stats.tx_dropped++;
netif_start_queue(sp->dev);
return;
}
p = icp; read_lock(&disc_data_lock);
sp = tty->disc_data;
if (sp)
atomic_inc(&sp->refcnt);
read_unlock(&disc_data_lock);
if (p[0] > 5) { return sp;
printk(KERN_DEBUG "%s: invalid KISS command -- dropped\n", sp->dev->name); }
netif_start_queue(sp->dev);
return;
}
if ((p[0] != 0) && (len > 2)) {
printk(KERN_DEBUG "%s: KISS control packet too long -- dropped\n", sp->dev->name);
netif_start_queue(sp->dev);
return;
}
if ((p[0] == 0) && (len < 15)) {
printk(KERN_DEBUG "%s: bad AX.25 packet to transmit -- dropped\n", sp->dev->name);
netif_start_queue(sp->dev);
sp->stats.tx_dropped++;
return;
}
count = encode_sixpack(p, (unsigned char *) sp->xbuff, len, sp->tx_delay);
sp->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
switch (p[0]) {
case 1: sp->tx_delay = p[1]; return;
case 2: sp->persistence = p[1]; return;
case 3: sp->slottime = p[1]; return;
case 4: /* ignored */ return;
case 5: sp->duplex = p[1]; return;
}
if (p[0] == 0) { static void sp_put(struct sixpack *sp)
/* in case of fullduplex or DAMA operation, we don't take care {
about the state of the DCD or of any timers, as the determination if (atomic_dec_and_test(&sp->refcnt))
of the correct time to send is the job of the AX.25 layer. We send up(&sp->dead_sem);
immediately after data has arrived. */
if (sp->duplex == 1) {
sp->led_state = 0x70;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->tx_enable = 1;
actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, count);
sp->xleft = count - actual;
sp->xhead = sp->xbuff + actual;
sp->led_state = 0x60;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
} else {
sp->xleft = count;
sp->xhead = sp->xbuff;
sp->status2 = count;
if (sp->duplex == 0)
sp_start_tx_timer(sp);
}
}
} }
/* /*
...@@ -338,22 +479,17 @@ static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len) ...@@ -338,22 +479,17 @@ static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len)
*/ */
static void sixpack_write_wakeup(struct tty_struct *tty) static void sixpack_write_wakeup(struct tty_struct *tty)
{ {
struct sixpack *sp = sp_get(tty);
int actual; int actual;
struct sixpack *sp = (struct sixpack *) tty->disc_data;
/* First make sure we're connected. */
if (!sp || sp->magic != SIXPACK_MAGIC ||
!netif_running(sp->dev))
return;
if (sp->xleft <= 0) { if (sp->xleft <= 0) {
/* Now serial buffer is almost free & we can start /* Now serial buffer is almost free & we can start
* transmission of another packet */ * transmission of another packet */
sp->stats.tx_packets++; sp->stats.tx_packets++;
tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
sp->tx_enable = 0; sp->tx_enable = 0;
netif_wake_queue(sp->dev); netif_wake_queue(sp->dev);
return; goto out;
} }
if (sp->tx_enable == 1) { if (sp->tx_enable == 1) {
...@@ -361,79 +497,34 @@ static void sixpack_write_wakeup(struct tty_struct *tty) ...@@ -361,79 +497,34 @@ static void sixpack_write_wakeup(struct tty_struct *tty)
sp->xleft -= actual; sp->xleft -= actual;
sp->xhead += actual; sp->xhead += actual;
} }
}
/* ----------------------------------------------------------------------- */
/* Encapsulate an IP datagram and kick it into a TTY queue. */
static int sp_xmit(struct sk_buff *skb, struct net_device *dev) out:
{ sp_put(sp);
struct sixpack *sp = (struct sixpack *) dev->priv;
/* We were not busy, so we are now... :-) */
netif_stop_queue(dev);
sp->stats.tx_bytes += skb->len;
sp_encaps(sp, skb->data, skb->len);
dev_kfree_skb(skb);
return 0;
} }
/* ----------------------------------------------------------------------- */
/* perform the persistence/slottime algorithm for CSMA access. If the persistence /* Open the low-level part of the 6pack channel. */
check was successful, write the data to the serial driver. Note that in case static int sp_open(struct net_device *dev)
of DAMA operation, the data is not sent here. */
static void sp_xmit_on_air(unsigned long channel)
{ {
struct sixpack *sp = (struct sixpack *) channel; struct sixpack *sp = netdev_priv(dev);
int actual; char *rbuff, *xbuff = NULL;
static unsigned char random; int err = -ENOBUFS;
unsigned long len;
random = random * 17 + 41;
if (((sp->status1 & SIXP_DCD_MASK) == 0) && (random < sp->persistence)) {
sp->led_state = 0x70;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->tx_enable = 1;
actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, sp->status2);
sp->xleft -= actual;
sp->xhead += actual;
sp->led_state = 0x60;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->status2 = 0;
} else
sp_start_tx_timer(sp);
}
/* !!! length of the buffers. MTU is IP MTU, not PACLEN! */
/* Return the frame type ID */ len = dev->mtu * 2;
static int sp_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
void *daddr, void *saddr, unsigned len)
{
#ifdef CONFIG_INET
if (type != htons(ETH_P_AX25))
return ax25_encapsulate(skb, dev, type, daddr, saddr, len);
#endif
return 0;
}
rbuff = kmalloc(len + 4, GFP_KERNEL);
if (rbuff == NULL)
goto err_exit;
static int sp_rebuild_header(struct sk_buff *skb) xbuff = kmalloc(len + 4, GFP_KERNEL);
{ if (xbuff == NULL)
#ifdef CONFIG_INET goto err_exit;
return ax25_rebuild_header(skb);
#else
return 0;
#endif
}
spin_lock_bh(&sp->lock);
/* Open the low-level part of the 6pack channel. */
static int sp_open(struct net_device *dev)
{
struct sixpack *sp = (struct sixpack *) dev->priv;
unsigned long len;
if (sp->tty == NULL) if (sp->tty == NULL)
return -ENODEV; return -ENODEV;
...@@ -445,18 +536,8 @@ static int sp_open(struct net_device *dev) ...@@ -445,18 +536,8 @@ static int sp_open(struct net_device *dev)
* xbuff Transmit buffer. * xbuff Transmit buffer.
*/ */
/* !!! length of the buffers. MTU is IP MTU, not PACLEN! rbuff = xchg(&sp->rbuff, rbuff);
*/ xbuff = xchg(&sp->xbuff, xbuff);
len = dev->mtu * 2;
if ((sp->rbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL)
return -ENOMEM;
if ((sp->xbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL) {
kfree(sp->rbuff);
return -ENOMEM;
}
sp->mtu = AX25_MTU + 73; sp->mtu = AX25_MTU + 73;
sp->buffsize = len; sp->buffsize = len;
...@@ -465,7 +546,7 @@ static int sp_open(struct net_device *dev) ...@@ -465,7 +546,7 @@ static int sp_open(struct net_device *dev)
sp->rx_count_cooked = 0; sp->rx_count_cooked = 0;
sp->xleft = 0; sp->xleft = 0;
sp->flags &= (1 << SIXPF_INUSE); /* Clear ESCAPE & ERROR flags */ sp->flags = 0; /* Clear ESCAPE & ERROR flags */
sp->duplex = 0; sp->duplex = 0;
sp->tx_delay = SIXP_TXDELAY; sp->tx_delay = SIXP_TXDELAY;
...@@ -482,49 +563,47 @@ static int sp_open(struct net_device *dev) ...@@ -482,49 +563,47 @@ static int sp_open(struct net_device *dev)
init_timer(&sp->tx_t); init_timer(&sp->tx_t);
init_timer(&sp->resync_t); init_timer(&sp->resync_t);
return 0;
}
/* Close the low-level part of the 6pack channel. */
static int sp_close(struct net_device *dev)
{
struct sixpack *sp = (struct sixpack *) dev->priv;
if (sp->tty == NULL) spin_unlock_bh(&sp->lock);
return -EBUSY;
sp->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP); err = 0;
netif_stop_queue(dev); err_exit:
return 0; if (xbuff)
kfree(xbuff);
if (rbuff)
kfree(rbuff);
return err;
} }
static int sixpack_receive_room(struct tty_struct *tty) static int sixpack_receive_room(struct tty_struct *tty)
{ {
return 65536; /* We can handle an infinite amount of data. :-) */ return 65536; /* We can handle an infinite amount of data. :-) */
} }
/* !!! receive state machine */
/* /*
* Handle the 'receiver data ready' interrupt. * Handle the 'receiver data ready' interrupt.
* This function is called by the 'tty_io' module in the kernel when * This function is called by the 'tty_io' module in the kernel when
* a block of 6pack data has been received, which can now be decapsulated * a block of 6pack data has been received, which can now be decapsulated
* and sent on to some IP layer for further processing. * and sent on to some IP layer for further processing.
*/ */
static void sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) static void sixpack_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{ {
struct sixpack *sp;
unsigned char buf[512]; unsigned char buf[512];
int count1; int count1;
struct sixpack *sp = (struct sixpack *) tty->disc_data; if (!count)
return;
if (!sp || sp->magic != SIXPACK_MAGIC || sp = sp_get(tty);
!netif_running(sp->dev) || !count) if (!sp)
return; return;
memcpy(buf, cp, count<sizeof(buf)? count:sizeof(buf)); memcpy(buf, cp, count < sizeof(buf) ? count : sizeof(buf));
/* Read the characters out of the buffer */ /* Read the characters out of the buffer */
...@@ -538,6 +617,67 @@ static void sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp, ...@@ -538,6 +617,67 @@ static void sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp,
} }
} }
sixpack_decode(sp, buf, count1); sixpack_decode(sp, buf, count1);
sp_put(sp);
if (test_and_clear_bit(TTY_THROTTLED, &tty->flags)
&& tty->driver->unthrottle)
tty->driver->unthrottle(tty);
}
/*
* Try to resync the TNC. Called by the resync timer defined in
* decode_prio_command
*/
static void resync_tnc(unsigned long channel)
{
struct sixpack *sp = (struct sixpack *) channel;
struct net_device *dev = sp->dev;
static char resync_cmd = 0xe8;
printk(KERN_INFO "%s: resyncing TNC\n", dev->name);
/* clear any data that might have been received */
sp->rx_count = 0;
sp->rx_count_cooked = 0;
/* reset state machine */
sp->status = 1;
sp->status1 = 1;
sp->status2 = 0;
sp->tnc_ok = 0;
/* resync the TNC */
sp->led_state = 0x60;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->tty->driver->write(sp->tty, 0, &resync_cmd, 1);
/* Start resync timer again -- the TNC might be still absent */
del_timer(&sp->resync_t);
sp->resync_t.data = (unsigned long) sp;
sp->resync_t.function = resync_tnc;
sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
add_timer(&sp->resync_t);
}
static inline int tnc_init(struct sixpack *sp)
{
unsigned char inbyte = 0xe8;
sp->tty->driver->write(sp->tty, 0, &inbyte, 1);
del_timer(&sp->resync_t);
sp->resync_t.data = (unsigned long) sp;
sp->resync_t.function = resync_tnc;
sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
add_timer(&sp->resync_t);
return 0;
} }
/* /*
...@@ -549,37 +689,33 @@ static void sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp, ...@@ -549,37 +689,33 @@ static void sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp,
*/ */
static int sixpack_open(struct tty_struct *tty) static int sixpack_open(struct tty_struct *tty)
{ {
struct sixpack *sp = (struct sixpack *) tty->disc_data; struct sixpack *sp;
int err; int err = 0;
/* First make sure we're not already connected. */ if (!capable(CAP_NET_ADMIN))
return -EPERM;
if (sp && sp->magic == SIXPACK_MAGIC) sp = sp_alloc();
return -EEXIST; if (!sp) {
err = -ENOMEM;
goto out;
}
/* OK. Find a free 6pack channel to use. */
if ((sp = sp_alloc()) == NULL)
return -ENFILE;
sp->tty = tty; sp->tty = tty;
tty->disc_data = sp; atomic_set(&sp->refcnt, 1);
if (tty->driver->flush_buffer) init_MUTEX_LOCKED(&sp->dead_sem);
tty->driver->flush_buffer(tty);
if (tty->ldisc.flush_buffer)
tty->ldisc.flush_buffer(tty);
/* Restore default settings */
sp->dev->type = ARPHRD_AX25;
/* Perform the low-level 6pack initialization. */ /* Perform the low-level 6pack initialization. */
if ((err = sp_open(sp->dev))) if ((err = sp_open(sp->dev)))
return err; goto out;
/* Done. We have linked the TTY line to a channel. */ /* Done. We have linked the TTY line to a channel. */
tty->disc_data = sp;
tnc_init(sp); tnc_init(sp);
return sp->dev->base_addr; out:
return err;
} }
...@@ -593,102 +729,93 @@ static void sixpack_close(struct tty_struct *tty) ...@@ -593,102 +729,93 @@ static void sixpack_close(struct tty_struct *tty)
{ {
struct sixpack *sp = (struct sixpack *) tty->disc_data; struct sixpack *sp = (struct sixpack *) tty->disc_data;
/* First make sure we're connected. */ write_lock(&disc_data_lock);
if (!sp || sp->magic != SIXPACK_MAGIC) sp = tty->disc_data;
tty->disc_data = 0;
write_unlock(&disc_data_lock);
if (sp == 0)
return; return;
rtnl_lock(); /*
dev_close(sp->dev); * We have now ensured that nobody can start using ap from now on, but
* we have to wait for all existing users to finish.
*/
if (!atomic_dec_and_test(&sp->refcnt))
down(&sp->dead_sem);
del_timer(&sp->tx_t); del_timer(&sp->tx_t);
del_timer(&sp->resync_t); del_timer(&sp->resync_t);
tty->disc_data = 0;
sp->tty = NULL;
sp_free(sp); sp_free(sp);
unregister_netdevice(sp->dev); unregister_netdev(sp->dev);
rtnl_unlock();
}
static struct net_device_stats *sp_get_stats(struct net_device *dev)
{
struct sixpack *sp = (struct sixpack *) dev->priv;
return &sp->stats;
} }
static int sp_set_mac_address(struct net_device *dev, void *addr) static int sp_set_mac_address(struct net_device *dev, void *addr)
{ {
return copy_from_user(dev->dev_addr, addr, AX25_ADDR_LEN) ? -EFAULT : 0; return copy_from_user(dev->dev_addr, addr, AX25_ADDR_LEN) ? -EFAULT : 0;
} }
static int sp_set_dev_mac_address(struct net_device *dev, void *addr)
{
struct sockaddr *sa = addr;
memcpy(dev->dev_addr, sa->sa_data, AX25_ADDR_LEN);
return 0;
}
/* Perform I/O control on an active 6pack channel. */ /* Perform I/O control on an active 6pack channel. */
static int sixpack_ioctl(struct tty_struct *tty, void *file, int cmd, void *arg) static int sixpack_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{ {
struct sixpack *sp = (struct sixpack *) tty->disc_data; struct sixpack *sp = sp_get(tty);
unsigned int tmp; unsigned int tmp, err;
/* First make sure we're connected. */ if (!sp)
if (!sp || sp->magic != SIXPACK_MAGIC) return -ENXIO;
return -EINVAL;
switch(cmd) { switch(cmd) {
case SIOCGIFNAME: case SIOCGIFNAME:
return copy_to_user(arg, sp->dev->name, strlen(sp->dev->name) + 1) ? -EFAULT : 0; err = copy_to_user((void *) arg, sp->dev->name,
strlen(sp->dev->name) + 1) ? -EFAULT : 0;
break;
case SIOCGIFENCAP: case SIOCGIFENCAP:
return put_user(0, (int *)arg); err = put_user(0, (int *)arg);
break;
case SIOCSIFENCAP: case SIOCSIFENCAP:
if (get_user(tmp, (int *) arg)) if (get_user(tmp, (int *) arg)) {
return -EFAULT; err = -EFAULT;
break;
}
sp->mode = tmp; sp->mode = tmp;
sp->dev->addr_len = AX25_ADDR_LEN; /* sizeof an AX.25 addr */ sp->dev->addr_len = AX25_ADDR_LEN; /* sizeof an AX.25 addr */
sp->dev->hard_header_len = AX25_KISS_HEADER_LEN + AX25_MAX_HEADER_LEN + 3; sp->dev->hard_header_len = AX25_KISS_HEADER_LEN + AX25_MAX_HEADER_LEN + 3;
sp->dev->type = ARPHRD_AX25; sp->dev->type = ARPHRD_AX25;
return 0; err = 0;
break;
case SIOCSIFHWADDR: case SIOCSIFHWADDR:
return sp_set_mac_address(sp->dev, arg); err = sp_set_mac_address(sp->dev, (void *) arg);
break;
/* Allow stty to read, but not set, the serial port */ /* Allow stty to read, but not set, the serial port */
case TCGETS: case TCGETS:
case TCGETA: case TCGETA:
return n_tty_ioctl(tty, (struct file *) file, cmd, (unsigned long) arg); err = n_tty_ioctl(tty, (struct file *) file, cmd, arg);
break;
default: default:
return -ENOIOCTLCMD; return -ENOIOCTLCMD;
} }
}
static int sp_open_dev(struct net_device *dev) sp_put(sp);
{
struct sixpack *sp = (struct sixpack *) dev->priv; return err;
if (sp->tty == NULL)
return -ENODEV;
return 0;
} }
/* Fill in our line protocol discipline */ /* Fill in our line protocol discipline */
static struct tty_ldisc sp_ldisc = { static struct tty_ldisc sp_ldisc = {
.magic = TTY_LDISC_MAGIC, .owner = THIS_MODULE,
.magic = TTY_LDISC_MAGIC,
.name = "6pack", .name = "6pack",
.open = sixpack_open, .open = sixpack_open,
.close = sixpack_close, .close = sixpack_close,
.ioctl = (int (*)(struct tty_struct *, struct file *, .ioctl = sixpack_ioctl,
unsigned int, unsigned long)) sixpack_ioctl,
.receive_buf = sixpack_receive_buf, .receive_buf = sixpack_receive_buf,
.receive_room = sixpack_receive_room, .receive_room = sixpack_receive_room,
.write_wakeup = sixpack_write_wakeup, .write_wakeup = sixpack_write_wakeup,
...@@ -696,34 +823,18 @@ static struct tty_ldisc sp_ldisc = { ...@@ -696,34 +823,18 @@ static struct tty_ldisc sp_ldisc = {
/* Initialize 6pack control device -- register 6pack line discipline */ /* Initialize 6pack control device -- register 6pack line discipline */
static char msg_banner[] __initdata = KERN_INFO "AX.25: 6pack driver, " SIXPACK_VERSION " (dynamic channels, max=%d)\n"; static char msg_banner[] __initdata = KERN_INFO "AX.25: 6pack driver, " SIXPACK_VERSION "\n";
static char msg_nomem[] __initdata = KERN_ERR "6pack: can't allocate sixpack_ctrls[] array! No 6pack available.\n";
static char msg_regfail[] __initdata = KERN_ERR "6pack: can't register line discipline (err = %d)\n"; static char msg_regfail[] __initdata = KERN_ERR "6pack: can't register line discipline (err = %d)\n";
static int __init sixpack_init_driver(void) static int __init sixpack_init_driver(void)
{ {
int status; int status;
/* Do sanity checks on maximum device parameter. */ printk(msg_banner);
if (sixpack_maxdev < 4)
sixpack_maxdev = 4;
printk(msg_banner, sixpack_maxdev);
sixpack_ctrls = (sixpack_ctrl_t **) kmalloc(sizeof(void*)*sixpack_maxdev, GFP_KERNEL);
if (sixpack_ctrls == NULL) {
printk(msg_nomem);
return -ENOMEM;
}
/* Clear the pointer array, we allocate devices when we need them */
memset(sixpack_ctrls, 0, sizeof(void*)*sixpack_maxdev); /* Pointers */
/* Register the provided line protocol discipline */ /* Register the provided line protocol discipline */
if ((status = tty_register_ldisc(N_6PACK, &sp_ldisc)) != 0) { if ((status = tty_register_ldisc(N_6PACK, &sp_ldisc)) != 0)
printk(msg_regfail, status); printk(msg_regfail, status);
kfree(sixpack_ctrls);
}
return status; return status;
} }
...@@ -732,36 +843,16 @@ static const char msg_unregfail[] __exitdata = KERN_ERR "6pack: can't unregister ...@@ -732,36 +843,16 @@ static const char msg_unregfail[] __exitdata = KERN_ERR "6pack: can't unregister
static void __exit sixpack_exit_driver(void) static void __exit sixpack_exit_driver(void)
{ {
int i; int ret;
if ((i = tty_register_ldisc(N_6PACK, NULL)))
printk(msg_unregfail, i);
for (i = 0; i < sixpack_maxdev; i++) { if ((ret = tty_register_ldisc(N_6PACK, NULL)))
if (sixpack_ctrls[i]) { printk(msg_unregfail, ret);
/*
* VSV = if dev->start==0, then device
* unregistered while close proc.
*/
if (netif_running(&sixpack_ctrls[i]->dev))
unregister_netdev(&sixpack_ctrls[i]->dev);
kfree(sixpack_ctrls[i]);
}
}
kfree(sixpack_ctrls);
} }
/* Initialize the 6pack driver. Called by DDI. */ /* Initialize the 6pack driver. Called by DDI. */
static int sixpack_init(struct net_device *dev) static int sixpack_init(struct net_device *dev)
{ {
struct sixpack *sp = (struct sixpack *) dev->priv; struct sixpack *sp = netdev_priv(dev);
static char ax25_bcast[AX25_ADDR_LEN] =
{'Q'<<1,'S'<<1,'T'<<1,' '<<1,' '<<1,' '<<1,'0'<<1};
static char ax25_test[AX25_ADDR_LEN] =
{'L'<<1,'I'<<1,'N'<<1,'U'<<1,'X'<<1,' '<<1,'1'<<1};
if (sp == NULL) /* Allocation failed ?? */ if (sp == NULL) /* Allocation failed ?? */
return -ENODEV; return -ENODEV;
...@@ -769,52 +860,15 @@ static int sixpack_init(struct net_device *dev) ...@@ -769,52 +860,15 @@ static int sixpack_init(struct net_device *dev)
/* Set up the "6pack Control Block". (And clear statistics) */ /* Set up the "6pack Control Block". (And clear statistics) */
memset(sp, 0, sizeof (struct sixpack)); memset(sp, 0, sizeof (struct sixpack));
sp->magic = SIXPACK_MAGIC;
sp->dev = dev; sp->dev = dev;
/* Finish setting up the DEVICE info. */
dev->mtu = SIXP_MTU;
dev->hard_start_xmit = sp_xmit;
dev->open = sp_open_dev;
dev->stop = sp_close;
dev->hard_header = sp_header;
dev->get_stats = sp_get_stats;
dev->set_mac_address = sp_set_dev_mac_address;
dev->hard_header_len = AX25_MAX_HEADER_LEN;
dev->addr_len = AX25_ADDR_LEN;
dev->type = ARPHRD_AX25;
dev->tx_queue_len = 10;
dev->rebuild_header = sp_rebuild_header;
dev->tx_timeout = NULL;
memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN); /* Only activated in AX.25 mode */
memcpy(dev->dev_addr, ax25_test, AX25_ADDR_LEN); /* "" "" "" "" */
/* New-style flags. */
dev->flags = 0;
return 0; return 0;
} }
/* ----> 6pack timer interrupt handler and friends. <---- */
static void sp_start_tx_timer(struct sixpack *sp)
{
int when = sp->slottime;
del_timer(&sp->tx_t);
sp->tx_t.data = (unsigned long) sp;
sp->tx_t.function = sp_xmit_on_air;
sp->tx_t.expires = jiffies + ((when+1)*HZ)/100;
add_timer(&sp->tx_t);
}
/* encode an AX.25 packet into 6pack */ /* encode an AX.25 packet into 6pack */
static int encode_sixpack(unsigned char *tx_buf, unsigned char *tx_buf_raw, int length, unsigned char tx_delay) static int encode_sixpack(unsigned char *tx_buf, unsigned char *tx_buf_raw,
int length, unsigned char tx_delay)
{ {
int count = 0; int count = 0;
unsigned char checksum = 0, buf[400]; unsigned char checksum = 0, buf[400];
...@@ -849,47 +903,28 @@ static int encode_sixpack(unsigned char *tx_buf, unsigned char *tx_buf_raw, int ...@@ -849,47 +903,28 @@ static int encode_sixpack(unsigned char *tx_buf, unsigned char *tx_buf_raw, int
return raw_count; return raw_count;
} }
/* decode 4 sixpack-encoded bytes into 3 data bytes */
/* decode a 6pack packet */ static void decode_data(unsigned char inbyte, struct sixpack *sp)
static void
sixpack_decode(struct sixpack *sp, unsigned char pre_rbuff[], int count)
{
unsigned char inbyte;
int count1;
for (count1 = 0; count1 < count; count1++) {
inbyte = pre_rbuff[count1];
if (inbyte == SIXP_FOUND_TNC) {
printk(KERN_INFO "6pack: TNC found.\n");
sp->tnc_ok = 1;
del_timer(&sp->resync_t);
}
if ((inbyte & SIXP_PRIO_CMD_MASK) != 0)
decode_prio_command(inbyte, sp);
else if ((inbyte & SIXP_STD_CMD_MASK) != 0)
decode_std_command(inbyte, sp);
else if ((sp->status & SIXP_RX_DCD_MASK) == SIXP_RX_DCD_MASK)
decode_data(inbyte, sp);
}
}
static int tnc_init(struct sixpack *sp)
{ {
unsigned char inbyte = 0xe8; unsigned char *buf;
sp->tty->driver->write(sp->tty, 0, &inbyte, 1); if (sp->rx_count != 3) {
sp->raw_buf[sp->rx_count++] = inbyte;
del_timer(&sp->resync_t); return;
sp->resync_t.data = (unsigned long) sp; }
sp->resync_t.function = resync_tnc;
sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
add_timer(&sp->resync_t);
return 0; buf = sp->raw_buf;
sp->cooked_buf[sp->rx_count_cooked++] =
buf[0] | ((buf[1] << 2) & 0xc0);
sp->cooked_buf[sp->rx_count_cooked++] =
(buf[1] & 0x0f) | ((buf[2] << 2) & 0xf0);
sp->cooked_buf[sp->rx_count_cooked++] =
(buf[2] & 0x03) | (inbyte << 2);
sp->rx_count = 0;
} }
/* identify and execute a 6pack priority command byte */ /* identify and execute a 6pack priority command byte */
static void decode_prio_command(unsigned char cmd, struct sixpack *sp) static void decode_prio_command(unsigned char cmd, struct sixpack *sp)
...@@ -916,8 +951,7 @@ static void decode_prio_command(unsigned char cmd, struct sixpack *sp) ...@@ -916,8 +951,7 @@ static void decode_prio_command(unsigned char cmd, struct sixpack *sp)
cmd &= !SIXP_RX_DCD_MASK; cmd &= !SIXP_RX_DCD_MASK;
} }
sp->status = cmd & SIXP_PRIO_DATA_MASK; sp->status = cmd & SIXP_PRIO_DATA_MASK;
} } else { /* output watchdog char if idle */
else { /* output watchdog char if idle */
if ((sp->status2 != 0) && (sp->duplex == 1)) { if ((sp->status2 != 0) && (sp->duplex == 1)) {
sp->led_state = 0x70; sp->led_state = 0x70;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1); sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
...@@ -948,46 +982,6 @@ static void decode_prio_command(unsigned char cmd, struct sixpack *sp) ...@@ -948,46 +982,6 @@ static void decode_prio_command(unsigned char cmd, struct sixpack *sp)
sp->status1 = cmd & SIXP_PRIO_DATA_MASK; sp->status1 = cmd & SIXP_PRIO_DATA_MASK;
} }
/* try to resync the TNC. Called by the resync timer defined in
decode_prio_command */
static void resync_tnc(unsigned long channel)
{
static char resync_cmd = 0xe8;
struct sixpack *sp = (struct sixpack *) channel;
printk(KERN_INFO "6pack: resyncing TNC\n");
/* clear any data that might have been received */
sp->rx_count = 0;
sp->rx_count_cooked = 0;
/* reset state machine */
sp->status = 1;
sp->status1 = 1;
sp->status2 = 0;
sp->tnc_ok = 0;
/* resync the TNC */
sp->led_state = 0x60;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
sp->tty->driver->write(sp->tty, 0, &resync_cmd, 1);
/* Start resync timer again -- the TNC might be still absent */
del_timer(&sp->resync_t);
sp->resync_t.data = (unsigned long) sp;
sp->resync_t.function = resync_tnc;
sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
add_timer(&sp->resync_t);
}
/* identify and execute a standard 6pack command byte */ /* identify and execute a standard 6pack command byte */
static void decode_std_command(unsigned char cmd, struct sixpack *sp) static void decode_std_command(unsigned char cmd, struct sixpack *sp)
...@@ -997,67 +991,70 @@ static void decode_std_command(unsigned char cmd, struct sixpack *sp) ...@@ -997,67 +991,70 @@ static void decode_std_command(unsigned char cmd, struct sixpack *sp)
channel = cmd & SIXP_CHN_MASK; channel = cmd & SIXP_CHN_MASK;
switch (cmd & SIXP_CMD_MASK) { /* normal command */ switch (cmd & SIXP_CMD_MASK) { /* normal command */
case SIXP_SEOF: case SIXP_SEOF:
if ((sp->rx_count == 0) && (sp->rx_count_cooked == 0)) { if ((sp->rx_count == 0) && (sp->rx_count_cooked == 0)) {
if ((sp->status & SIXP_RX_DCD_MASK) == if ((sp->status & SIXP_RX_DCD_MASK) ==
SIXP_RX_DCD_MASK) { SIXP_RX_DCD_MASK) {
sp->led_state = 0x68; sp->led_state = 0x68;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
}
} else {
sp->led_state = 0x60;
/* fill trailing bytes with zeroes */
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1); sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
rest = sp->rx_count;
if (rest != 0)
for (i = rest; i <= 3; i++)
decode_data(0, sp);
if (rest == 2)
sp->rx_count_cooked -= 2;
else if (rest == 3)
sp->rx_count_cooked -= 1;
for (i = 0; i < sp->rx_count_cooked; i++)
checksum += sp->cooked_buf[i];
if (checksum != SIXP_CHKSUM) {
printk(KERN_DEBUG "6pack: bad checksum %2.2x\n", checksum);
} else {
sp->rcount = sp->rx_count_cooked-2;
sp_bump(sp, 0);
}
sp->rx_count_cooked = 0;
} }
break; } else {
case SIXP_TX_URUN: printk(KERN_DEBUG "6pack: TX underrun\n"); sp->led_state = 0x60;
break; /* fill trailing bytes with zeroes */
case SIXP_RX_ORUN: printk(KERN_DEBUG "6pack: RX overrun\n"); sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
break; rest = sp->rx_count;
case SIXP_RX_BUF_OVL: if (rest != 0)
printk(KERN_DEBUG "6pack: RX buffer overflow\n"); for (i = rest; i <= 3; i++)
decode_data(0, sp);
if (rest == 2)
sp->rx_count_cooked -= 2;
else if (rest == 3)
sp->rx_count_cooked -= 1;
for (i = 0; i < sp->rx_count_cooked; i++)
checksum += sp->cooked_buf[i];
if (checksum != SIXP_CHKSUM) {
printk(KERN_DEBUG "6pack: bad checksum %2.2x\n", checksum);
} else {
sp->rcount = sp->rx_count_cooked-2;
sp_bump(sp, 0);
}
sp->rx_count_cooked = 0;
}
break;
case SIXP_TX_URUN: printk(KERN_DEBUG "6pack: TX underrun\n");
break;
case SIXP_RX_ORUN: printk(KERN_DEBUG "6pack: RX overrun\n");
break;
case SIXP_RX_BUF_OVL:
printk(KERN_DEBUG "6pack: RX buffer overflow\n");
} }
} }
/* decode 4 sixpack-encoded bytes into 3 data bytes */ /* decode a 6pack packet */
static void decode_data(unsigned char inbyte, struct sixpack *sp) static void
sixpack_decode(struct sixpack *sp, unsigned char pre_rbuff[], int count)
{ {
unsigned char *buf; unsigned char inbyte;
int count1;
if (sp->rx_count != 3) for (count1 = 0; count1 < count; count1++) {
sp->raw_buf[sp->rx_count++] = inbyte; inbyte = pre_rbuff[count1];
else { if (inbyte == SIXP_FOUND_TNC) {
buf = sp->raw_buf; printk(KERN_INFO "6pack: TNC found.\n");
sp->cooked_buf[sp->rx_count_cooked++] = sp->tnc_ok = 1;
buf[0] | ((buf[1] << 2) & 0xc0); del_timer(&sp->resync_t);
sp->cooked_buf[sp->rx_count_cooked++] = }
(buf[1] & 0x0f) | ((buf[2] << 2) & 0xf0); if ((inbyte & SIXP_PRIO_CMD_MASK) != 0)
sp->cooked_buf[sp->rx_count_cooked++] = decode_prio_command(inbyte, sp);
(buf[2] & 0x03) | (inbyte << 2); else if ((inbyte & SIXP_STD_CMD_MASK) != 0)
sp->rx_count = 0; decode_std_command(inbyte, sp);
else if ((sp->status & SIXP_RX_DCD_MASK) == SIXP_RX_DCD_MASK)
decode_data(inbyte, sp);
} }
} }
MODULE_AUTHOR("Ralf Baechle DO1GRB <ralf@linux-mips.org>");
MODULE_AUTHOR("Andreas Knsgen <ajk@ccac.rwth-aachen.de>");
MODULE_DESCRIPTION("6pack driver for AX.25"); MODULE_DESCRIPTION("6pack driver for AX.25");
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
MODULE_ALIAS_LDISC(N_6PACK); MODULE_ALIAS_LDISC(N_6PACK);
......
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