patch-2.1.71 linux/drivers/net/pt.c

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diff -u --recursive --new-file v2.1.70/linux/drivers/net/pt.c linux/drivers/net/pt.c
@@ -1,1778 +0,0 @@
-#undef PT_DEBUG 1
-/*
- * pt.c: Linux device driver for the Gracilis PackeTwin.
- * Copyright (c) 1995 Craig Small VK2XLZ (vk2xlz@vk2xlz.ampr.org.)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2, 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., 675 Mass Ave, Cambridge MA 02139, USA.
- *
- * This driver is largely based upon the PI driver by David Perry.
- *
- * Revision History
- * 23/02/95 cs  Started again on driver, last one scrapped
- * 27/02/95 cs  Program works, we have chan A only.  Tx stays on
- * 28/02/95 cs  Fix Tx problem (& TxUIE instead of | )
- *		Fix Chan B Tx timer problem, used TMR2 instead of TMR1
- * 03/03/95 cs  Painfully found out (after 3 days) SERIAL_CFG is write only
- *              created image of it and DMA_CFG
- * 21/06/95 cs  Upgraded to suit PI driver 0.8 ALPHA
- * 22/08/95 cs	Changed it all around to make it like pi driver
- * 23/08/95 cs  It now works, got caught again by TMR2 and we must have
- *				auto-enables for daughter boards.
- * 07/10/95 cs  Fixed for 1.3.30 (hopefully)
- * 26/11/95 cs  Fixed for 1.3.43, ala 29/10 for pi2.c by ac
- * 21/12/95 cs  Got rid of those nasty warnings when compiling, for 1.3.48
- * 08/08/96 jsn Convert to use as a module. Removed send_kiss, empty_scc and
- *		pt_loopback functions - they were unused.
- * 13/12/96 jsn Fixed to match Linux networking changes.
- */
-
-/*
- * default configuration of the PackeTwin,
- * ie What Craig uses his PT for.
- */
-#define PT_DMA 3
-
-#define DEF_A_SPEED	4800		/* 4800 baud */
-#define DEF_A_TXDELAY	350		/* 350 mS */
-#define DEF_A_PERSIST	64		/* 25% persistence */
-#define DEF_A_SLOTIME	10		/* 10 mS */
-#define DEF_A_SQUELDELAY 30		/* 30 mS */
-#define DEF_A_CLOCKMODE	0		/* Normal clock mode */
-#define DEF_A_NRZI		1		/* NRZI mode */
-
-#define DEF_B_SPEED	0		/* 0 means external clock */
-#define DEF_B_TXDELAY	250		/* 250 mS */
-#define DEF_B_PERSIST	64		/* 25% */
-#define DEF_B_SLOTIME	10		/* 10 mS */
-#define DEF_B_SQUELDELAY 30		/* 30 mS */
-#define DEF_B_CLOCKMODE 0 		/* Normal clock mode ?!? */
-#define DEF_B_NRZI		1		/* NRZI mode */
-
-
-#define	PARAM_TXDELAY	1
-#define	PARAM_PERSIST	2
-#define	PARAM_SLOTTIME	3
-#define	PARAM_FULLDUP	5
-#define	PARAM_HARDWARE	6
-#define	PARAM_RETURN	255
-
-#include <linux/config.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/types.h>
-#include <linux/fcntl.h>
-#include <linux/interrupt.h>
-#include <linux/ptrace.h>
-#include <linux/ioport.h>
-#include <linux/in.h>
-#include <linux/malloc.h>
-#include <linux/string.h>
-#include <linux/errno.h>
-#include <asm/system.h>
-#include <asm/bitops.h>
-#include <asm/io.h>
-#include <asm/dma.h>
-#include <asm/uaccess.h>
-#include <linux/inet.h>
-#include <linux/netdevice.h>
-#include <linux/etherdevice.h>
-#include <linux/skbuff.h>
-#include <linux/timer.h>
-#include <linux/if_arp.h>
-#include <linux/pt.h>
-#include <linux/init.h>
-#include "z8530.h"
-#include <net/ax25.h>
-
-struct mbuf {
-    struct mbuf *next;
-    int cnt;
-    char data[0];
-};
-
-/*
- * The actual PT devices we will use
- */
-static int pt0_preprobe(struct device *dev) {return 0;} /* Dummy probe function */
-static struct device pt0a = { "pt0a", 0, 0, 0, 0, 0, 0, 0, 0, 0, NULL, pt0_preprobe };
-static struct device pt0b = { "pt0b", 0, 0, 0, 0, 0, 0, 0, 0, 0, NULL, pt0_preprobe };
-
-/* Ok, they shouldn't be here, but both channels share them */
-/* The Images of the Serial and DMA config registers */
-static unsigned char pt_sercfg = 0;
-static unsigned char pt_dmacfg = 0;
-
-/* The number of IO ports used by the card */
-#define PT_TOTAL_SIZE   16
-
-/* Index to functions, as function prototypes. */
-
-static int pt_probe(struct device *dev);
-static int pt_open(struct device *dev);
-static int pt_send_packet(struct sk_buff *skb, struct device *dev);
-static void pt_interrupt(int irq, void *dev_id, struct pt_regs *regs);
-static int pt_close(struct device *dev);
-static int pt_ioctl(struct device *dev, struct ifreq *ifr, int cmd);
-static struct net_device_stats *pt_get_stats(struct device *dev);
-static void pt_rts(struct pt_local *lp, int x);
-static void pt_rxisr(struct device *dev);
-static void pt_txisr(struct pt_local *lp);
-static void pt_exisr(struct pt_local *lp);
-static void pt_tmrisr(struct pt_local *lp);
-static char *get_dma_buffer(unsigned long *mem_ptr);
-static int valid_dma_page(unsigned long addr, unsigned long dev_buffsize);
-static int hw_probe(int ioaddr);
-static void tdelay(struct pt_local *lp, int time);
-static void chipset_init(struct device *dev);
-
-static char ax25_bcast[7] =
-{'Q' << 1, 'S' << 1, 'T' << 1, ' ' << 1, ' ' << 1, ' ' << 1, '0' << 1};
-static char ax25_test[7] =
-{'L' << 1, 'I' << 1, 'N' << 1, 'U' << 1, 'X' << 1, ' ' << 1, '1' << 1};
-
-
-
-static int ext2_secrm_seed = 152;
-
-static inline unsigned char random(void)
-{
-    return (unsigned char) (ext2_secrm_seed = ext2_secrm_seed * 60691 + 1);
-}
-
-static inline void wrtscc(int cbase, int ctl, int sccreg, unsigned char val)
-{
-    outb_p(sccreg, ctl);        /* Select register */
-    outb_p(val, ctl);           /* Output value */
-}
-
-static inline unsigned char rdscc(int cbase, int ctl, int sccreg)
-{
-    unsigned char retval;
-
-    outb_p(sccreg, ctl);        /* Select register */
-    retval = inb_p(ctl);
-    return retval;
-}
-
-static void switchbuffers(struct pt_local *lp)
-{
-    if (lp->rcvbuf == lp->rxdmabuf1)
-	lp->rcvbuf = lp->rxdmabuf2;
-    else
-	lp->rcvbuf = lp->rxdmabuf1;
-}
-
-static void hardware_send_packet(struct pt_local *lp, struct sk_buff *skb)
-{
-	char kickflag;
-	unsigned long flags;
-	char *ptr;
-	struct device *dev;
-
-	/* First, let's see if this packet is actually a KISS packet */
-	ptr = skb->data;
-	if (ptr[0] != 0 && skb->len >= 2)
-	{
-#ifdef PT_DEBUG
-		printk(KERN_DEBUG "PT: Rx KISS... Control = %d, value = %d.\n", ptr[0], (skb->len > 1? ptr[1] : -1));
-#endif
-		/* Kludge to get device */
-		if ((struct pt_local*)(&pt0b.priv) == lp)
-			dev = &pt0b;
-		else
-			dev = &pt0a;
-		switch(ptr[0])
-		{
-
-			case PARAM_TXDELAY:
-				/*TxDelay is in 10mS increments */
-				lp->txdelay = ptr[1] * 10;
-				break;
-			case PARAM_PERSIST:
-				lp->persist = ptr[1];
-				break;
-			case PARAM_SLOTTIME:
-				lp->slotime = ptr[1];
-				break;
-			case PARAM_FULLDUP:
-				/* Yeah right, you wish!  Fullduplex is a little while to
-				 * go folks, but this is how you fire it up
-				 */
-				break;
-			/* Perhaps we should have txtail here?? */
-		} /*switch */
-		return;
-	}
-
-	lp->stats.tx_packets++;
-	lp->stats.tx_bytes+=skb->len;
-	save_flags(flags);
-	cli();
-	kickflag = (skb_peek(&lp->sndq) == NULL) && (lp->sndbuf == NULL);
-	restore_flags(flags);
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: hardware_send_packet(): kickflag = %d (%d).\n", kickflag, lp->base & CHANA);
-#endif
-	skb_queue_tail(&lp->sndq, skb);
-	if (kickflag) 
-	{
-        /* Simulate interrupt to transmit */
-        	if (lp->dmachan)
-			pt_txisr(lp);
-		else 
-		{
-            		save_flags(flags);
-	           	cli();
-            		if (lp->tstate == IDLE)
-                		pt_txisr(lp);
-            		restore_flags(flags);
-		}
-	}
-} /* hardware_send_packet() */
-
-static void setup_rx_dma(struct pt_local *lp)
-{
-	unsigned long flags;
-	int cmd;
-	unsigned long dma_abs;
-	unsigned char dmachan;
-
-	save_flags(flags);
-	cli();
-
-	dma_abs = (unsigned long) (lp->rcvbuf->data);
-	dmachan = lp->dmachan;
-	cmd = lp->base + CTL;
-
-	if(!valid_dma_page(dma_abs, DMA_BUFF_SIZE + sizeof(struct mbuf)))
-		panic("PI: RX buffer violates DMA boundary!");
-
-	/* Get ready for RX DMA */
-	wrtscc(lp->cardbase, cmd, R1, WT_FN_RDYFN | WT_RDY_RT | INT_ERR_Rx | EXT_INT_ENAB);
-
-	disable_dma(dmachan);
-	clear_dma_ff(dmachan);
-
-	/*
-	 *	Set DMA mode register to single transfers, incrementing address,
-	 *	auto init, writes
-	 */
-
-	set_dma_mode(dmachan, DMA_MODE_READ | 0x10);
-	set_dma_addr(dmachan, dma_abs);
-	set_dma_count(dmachan, lp->bufsiz);
-	enable_dma(dmachan);
-
-	/*
-	 *	If a packet is already coming in, this line is supposed to
-	 *	avoid receiving a partial packet.
-	 */
-
-	wrtscc(lp->cardbase, cmd, R0, RES_Rx_CRC);
-
-	/* Enable RX dma */
-	wrtscc(lp->cardbase, cmd, R1,
-		WT_RDY_ENAB | WT_FN_RDYFN | WT_RDY_RT | INT_ERR_Rx | EXT_INT_ENAB);
-
-	restore_flags(flags);
-}
-
-static void setup_tx_dma(struct pt_local *lp, int length)
-{
-    unsigned long dma_abs;
-    unsigned long flags;
-    unsigned long dmachan;
-
-    save_flags(flags);
-    cli();
-
-    dmachan = lp->dmachan;
-    dma_abs = (unsigned long) (lp->txdmabuf);
-
-    if(!valid_dma_page(dma_abs, DMA_BUFF_SIZE + sizeof(struct mbuf)))
-	panic("PT: TX buffer violates DMA boundary!");
-
-    disable_dma(dmachan);
-    /* Set DMA mode register to single transfers, incrementing address,
-     *  no auto init, reads
-     */
-    set_dma_mode(dmachan, DMA_MODE_WRITE);
-    clear_dma_ff(dmachan);
-    set_dma_addr(dmachan, dma_abs);
-    /* output byte count */
-    set_dma_count(dmachan, length);
-
-    restore_flags(flags);
-}
-
-/*
- * This sets up all the registers in the SCC for the given channel
- * based upon tsync_hwint()
- */
-static void scc_init(struct device *dev)
-{
-	unsigned long flags;
-	struct pt_local *lp = (struct pt_local*) dev->priv;
-	register int cmd = lp->base + CTL;
-	int tc, br;
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: scc_init(): (%d).\n", lp->base & CHANA);
-#endif
-	save_flags(flags);
-	cli();
-
-	/* We may put something here to enable_escc */
-
-	if (cmd & CHANA)
-	{
-	        wrtscc(lp->cardbase, cmd, R9, CHRA);	/* Reset channel A */
-	        wrtscc(lp->cardbase, cmd, R2, 0xff);	/* Initialise interrupt vector */
-	}
-	else
-	    	wrtscc(lp->cardbase, cmd, R9, CHRB);	/* Reset channel B */
-
-	/* Deselect all Rx and Tx interrupts */
-	wrtscc(lp->cardbase, cmd, R1, 0);
-
-	/* Turn off external interrupts (like CTS/CD) */
-	wrtscc(lp->cardbase, cmd, R15, 0);
-
-	/* X1 clock, SDLC mode */
-	wrtscc(lp->cardbase, cmd, R4, SDLC | X1CLK);
-
-	/* Preset CRC and set mode */
-	if (lp->nrzi)
-	    	/* Preset Tx CRC, put into NRZI mode */
-		wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZI);
-	else
-		/* Preset Tx CRC, put into NRZ mode */
-		wrtscc(lp->cardbase, cmd, R10, CRCPS);
-
-	/* Tx/Rx parameters */
-	if (lp->speed)		/* Use internal clocking */
-	       /* Tx Clk from BRG. Rx Clk form DPLL, TRxC pin outputs DPLL */
-	       wrtscc(lp->cardbase, cmd, R11, TCBR | RCDPLL | TRxCDP | TRxCOI);
-	else	/* Use external clocking */
-	{
-		/* Tx Clk from TRxCL. Rx Clk from RTxCL, TRxC pin if input */
-		wrtscc(lp->cardbase, cmd, R11, TCTRxCP | RCRTxCP | TRxCBR);
-        	wrtscc(lp->cardbase,cmd, R14, 0);	/* wiz1 */
-	}
-
-	/* Null out SDLC start address */
-	wrtscc(lp->cardbase, cmd, R6, 0);
-
-	/* SDLC flag */
-	wrtscc(lp->cardbase, cmd, R7, FLAG);
-
-	/* Setup Tx but don't enable it */
-	wrtscc(lp->cardbase, cmd, R5, Tx8 | DTR);
-
-	/* Setup Rx */
-	wrtscc(lp->cardbase, cmd, R3, AUTO_ENAB | Rx8);
-
-	/* Setup the BRG, turn it off first */
-	wrtscc(lp->cardbase, cmd, R14, BRSRC);
-
-	/* set the 32x time constant for the BRG in Rx mode */
-	if (lp->speed)
-	{
-		br = lp->speed;
-		tc = ((lp->xtal / 32) / (br * 2)) - 2;
-		wrtscc(lp->cardbase, cmd, R12, tc & 0xff);		/* lower byte */
-   		wrtscc(lp->cardbase, cmd, R13, (tc >> 8) & 0xff);	/* upper byte */
-	}
-
-	/* Turn transmitter off, to setup stuff */
-   	pt_rts(lp, OFF);
-
-	/* External clocking */
-	if (lp->speed)
-	{
-		/* DPLL frm BRG, BRG src PCLK */
-		wrtscc(lp->cardbase, cmd, R14, BRSRC | SSBR);
-		wrtscc(lp->cardbase, cmd, R14, BRSRC | SEARCH);	/* SEARCH mode, keep BRG src */
-		wrtscc(lp->cardbase, cmd, R14, BRSRC | BRENABL);	/* Enable the BRG */
-
-	    /* Turn off external clock port */
-		if (lp->base & CHANA)
-			outb_p( (pt_sercfg &= ~PT_EXTCLKA), (lp->cardbase + SERIAL_CFG) );
-		else
-			outb_p( (pt_sercfg &= ~PT_EXTCLKB), (lp->cardbase + SERIAL_CFG) );
-	}
-	else
-	{
-		/* DPLL frm rtxc,BRG src PCLK */
-		/* Turn on external clock port */
-		if (lp->base & CHANA)
-			outb_p( (pt_sercfg |= PT_EXTCLKA), (lp->cardbase + SERIAL_CFG) );
-		else
-			outb_p( (pt_sercfg |= PT_EXTCLKB), (lp->cardbase + SERIAL_CFG) );
-	}
-
-	if (!lp->dmachan)
-		wrtscc(lp->cardbase, cmd, R1, (INT_ALL_Rx | EXT_INT_ENAB));
-
-	wrtscc(lp->cardbase, cmd, R15, BRKIE);	/* ABORT int */
-
-	/* Turn on the DTR to tell modem we're alive */
-	if (lp->base & CHANA)
-		outb_p( (pt_sercfg |= PT_DTRA_ON), (lp->cardbase + SERIAL_CFG) );
-	else
-	    	outb_p( (pt_sercfg |= PT_DTRB_ON), (lp->cardbase + SERIAL_CFG) );
-
-	/* Now, turn on the receiver and hunt for a flag */
-	wrtscc(lp->cardbase, cmd, R3, RxENABLE | RxCRC_ENAB | AUTO_ENAB | Rx8 );
-
-	restore_flags(flags);
-
-} /* scc_init() */
-
-/* Resets the given channel and whole SCC if both channels off */
-static void chipset_init(struct device *dev)
-{
-
-	struct pt_local *lp = (struct pt_local*) dev->priv;
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: chipset_init(): pt0a tstate = %d.\n", ((struct pt_local*)pt0a.priv)->tstate);
-	printk(KERN_DEBUG "PT: chipset_init(): pt0b tstate = %d.\n", ((struct pt_local*)pt0b.priv)->tstate);
-#endif
-	/* Reset SCC if both channels are to be canned */
-	if ( ((lp->base & CHANA) && !(pt_sercfg & PT_DTRB_ON)) ||
-			(!(lp->base & CHANA) && !(pt_sercfg & PT_DTRA_ON)) )
-	{
-		wrtscc(lp->cardbase, lp->base + CTL, R9, FHWRES);
-        	/* Reset int and dma registers */
-	        outb_p((pt_sercfg = 0), lp->cardbase + SERIAL_CFG);
-	        outb_p((pt_dmacfg = 0), lp->cardbase + DMA_CFG);
-#ifdef PT_DEBUG
-		printk(KERN_DEBUG "PT: chipset_init() Resetting SCC, called by ch (%d).\n", lp->base & CHANA);
-#endif
-	}
-	/* Reset individual channel */
-    	if (lp->base & CHANA) {
-        	wrtscc(lp->cardbase, lp->base + CTL, R9, MIE | DLC | NV | CHRA);
-        	outb_p( (pt_sercfg &= ~PT_DTRA_ON), lp->cardbase + SERIAL_CFG);
-    	} else {
-        	wrtscc(lp->cardbase, lp->base + CTL, R9, MIE | DLC | NV | CHRB);
-			outb_p( (pt_sercfg &= ~PT_DTRB_ON), lp->cardbase + SERIAL_CFG);
-	}
-} /* chipset_init() */
-
-
-
-__initfunc(int pt_init(void))
-{
-    int *port;
-    int ioaddr = 0;
-    int card_type = 0;
-    int ports[] =
-    { 0x230, 0x240, 0x250, 0x260, 0x270, 0x280, 0x290, 0x2a0,
-      0x2b0, 0x300, 0x330, 0x3f0,  0};
-
-    printk(KERN_INFO "PT: 0.41 ALPHA 07 October 1995 Craig Small (csmall@small.dropbear.id.au)\n");
-
-    for (port = &ports[0]; *port && !card_type; port++) {
-        ioaddr = *port;
-
-        if (check_region(ioaddr, PT_TOTAL_SIZE) == 0) {
-            printk(KERN_INFO "PT: Probing for card at address %#3x\n", ioaddr);
-            card_type = hw_probe(ioaddr);
-        }
-    }
-    if (card_type) {
-        printk(KERN_INFO "PT: Found a PT at address %#3x\n",ioaddr);
-    } else {
-        printk(KERN_ERR "PT: ERROR: No card found.\n");
-        return -EIO;
-    }
-
-    /*
-     * Link a couple of device structures into the chain
-     *
-     * For the A port
-     * Allocate space for 4 buffers even though we only need 3,
-     * because one of them may cross a DMA page boundary and
-     * be rejected by get_dma_buffer().
-     */
-    register_netdev(&pt0a);
-
-    pt0a.priv= kmalloc(sizeof(struct pt_local) + (DMA_BUFF_SIZE + sizeof(struct mbuf)) * 4, GFP_KERNEL | GFP_DMA);
-
-    pt0a.dma = 0;	/* wizzer - no dma yet */
-    pt0a.base_addr = ioaddr + CHANA;
-    pt0a.irq = 0;
-
-    /* And B port */
-    register_netdev(&pt0b);
-
-    pt0b.priv= kmalloc(sizeof(struct pt_local) + (DMA_BUFF_SIZE + sizeof(struct mbuf)) * 4, GFP_KERNEL | GFP_DMA);
-
-    pt0b.base_addr = ioaddr + CHANB;
-    pt0b.irq = 0;
-
-    /* Now initialise them */
-    pt_probe(&pt0a);
-    pt_probe(&pt0b);
-
-    pt0b.irq = pt0a.irq;	/* IRQ is shared */
-
-    return 0;
-} /* pt_init() */
-
-/*
- * Probe for PT card.  Also initialises the timers
- */
-__initfunc(static int hw_probe(int ioaddr))
-{
-    int time = 1000;		/* Number of milliseconds to test */
-    int a = 1;
-    int b = 1;
-    unsigned long start_time, end_time;
-
-    inb_p(ioaddr + TMR1CLR);
-    inb_p(ioaddr + TMR2CLR);
-
-    /* Timer counter channel 0, 1mS period */
-    outb_p(SC0 | LSB_MSB | MODE3, ioaddr + TMRCMD);
-    outb_p(0x00, ioaddr + TMR0);
-    outb_p(0x18, ioaddr + TMR0);
-
-    /* Setup timer control word for timer 1 */
-    outb_p(SC1 | LSB_MSB | MODE0, ioaddr + TMRCMD);
-    outb_p((time << 1) & 0xff, ioaddr + TMR1);
-    outb_p((time >> 7) & 0xff, ioaddr + TMR1);
-
-    /* wait until counter reg is loaded */
-    do {
-        /* Latch count for reading */
-        outb_p(SC1, ioaddr + TMRCMD);
-        a = inb_p(ioaddr + TMR1);
-        b = inb_p(ioaddr + TMR1);
-    } while (b == 0);
-    start_time = jiffies;
-    while(b != 0)
-    {
-        /* Latch count for reading */
-        outb_p(SC1, ioaddr + TMRCMD);
-        a = inb_p(ioaddr + TMR1);
-        b = inb_p(ioaddr + TMR1);
-        end_time = jiffies;
-        /* Don't wait forever - there may be no card here */
-        if ((end_time - start_time) > 200)
-        {
-        	inb_p(ioaddr + TMR1CLR);
-            return 0;
-        }
-    }
-
-    /* Now fix the timers up for general operation */
-
-    /* Clear the timers */
-    inb_p(ioaddr + TMR1CLR);
-    inb_p(ioaddr + TMR2CLR);
-
-    outb_p(SC1 | LSB_MSB | MODE0, ioaddr + TMRCMD);
-    inb_p(ioaddr + TMR1CLR);
-
-    outb_p(SC2 | LSB_MSB | MODE0, ioaddr + TMRCMD);
-    /* Should this be tmr1 or tmr2? wiz3*/
-    inb_p(ioaddr + TMR1CLR);
-
-    return 1;
-} /* hw_probe() */
-
-
-static void pt_rts(struct pt_local *lp, int x)
-{
-	int tc;
-	long br;
-	int cmd = lp->base + CTL;
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_rts(): Transmitter status will be %d (%d).\n", x, lp->base & CHANA);
-#endif
-	if (x == ON) {
-	    /* Ex ints off to avoid int */
-	    wrtscc(lp->cardbase, cmd, R15, 0);
-	    wrtscc(lp->cardbase, cmd, R3, AUTO_ENAB | Rx8);	/* Rx off */
-	    lp->rstate = IDLE;
-
-	    if(lp->dmachan)
-	    {
-	        /* Setup for Tx DMA */
-	        wrtscc(lp->cardbase, cmd, R1, WT_FN_RDYFN | EXT_INT_ENAB);
-	    } else {
-	        /* No interrupts */
-	        wrtscc(lp->cardbase, cmd, R1, 0);
-	    }
-
-            if (!lp->clockmode)
-            {
-                if (lp->speed)
-                {
-                    br = lp->speed;
-                    tc = (lp->xtal / (br * 2)) - 2;
-                    wrtscc(lp->cardbase, cmd, R12, tc & 0xff);
-                    wrtscc(lp->cardbase, cmd, R13, (tc >> 8) & 0xff);
-                }
-            }
-            /* Turn on Tx by raising RTS */
-            wrtscc(lp->cardbase, cmd, R5, TxCRC_ENAB | RTS | TxENAB | Tx8 | DTR);
-            /* Transmitter on now */
-        } else {		/* turning off Tx */
-            lp->tstate = IDLE;
-
-            /* Turn off Tx by dropping RTS */
-            wrtscc(lp->cardbase, cmd, R5, Tx8 | DTR);
-            if (!lp->clockmode)
-            {
-                if (lp->speed)		/* internally clocked */
-                {
-                    /* Reprogram BRG from 32x clock for Rx DPLL */
-                    /* BRG off, keep PClk source */
-                    wrtscc(lp->cardbase, cmd, R14, BRSRC);
-                    br = lp->speed;
-                    tc = ((lp->xtal / 32) / (br * 2)) - 2;
-                    wrtscc(lp->cardbase, cmd, R12, tc & 0xff);
-                    wrtscc(lp->cardbase, cmd, R13, (tc >> 8) & 0xff);
-
-                    /* SEARCH mode, BRG source */
-                    wrtscc(lp->cardbase, cmd, R14, BRSRC | SEARCH);
-                    /* Enable the BRG */
-                    wrtscc(lp->cardbase, cmd, R14, BRSRC | BRENABL);
-                }
-            }
-            /* Flush Rx fifo */
-            /* Turn Rx off */
-            wrtscc(lp->cardbase, cmd, R3, AUTO_ENAB | Rx8);
-
-            /* Reset error latch */
-            wrtscc(lp->cardbase, cmd, R0, ERR_RES);
-
-            /* get status byte from R1 */
-            (void) rdscc(lp->cardbase, cmd, R1);
-
-            /* Read and dump data in queue */
-            (void) rdscc(lp->cardbase, cmd, R8);
-            (void) rdscc(lp->cardbase, cmd, R8);
-            (void) rdscc(lp->cardbase, cmd, R8);
-
-            /* Now, turn on Rx and hunt for a flag */
-              wrtscc(lp->cardbase, cmd, R3, RxENABLE | AUTO_ENAB | Rx8 );
-
-            lp->rstate = ACTIVE;
-
-            if (lp->dmachan)
-            {
-                setup_rx_dma(lp);
-            } else {
-                /* Reset buffer pointers */
-                lp->rcp = lp->rcvbuf->data;
-                lp->rcvbuf->cnt = 0;
-                /* Allow aborts to interrupt us */
-                wrtscc(lp->cardbase, cmd, R1, INT_ALL_Rx | EXT_INT_ENAB);
-
-	}
-	wrtscc(lp->cardbase, cmd, R15, BRKIE );
-    }
-} /* pt_rts() */
-
-
-static int valid_dma_page(unsigned long addr, unsigned long dev_bufsize)
-{
-    if (((addr & 0xffff) + dev_bufsize) <= 0x10000)
-        return 1;
-    else
-        return 0;
-}
-
-static int pt_set_mac_address(struct device *dev, void *addr)
-{
-	struct sockaddr *sa = (struct sockaddr *)addr;
-	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);		/* addr is an AX.25 shifted ASCII */
-	return 0;		/* mac address */
-}
-
-
-/* Allocate a buffer which does not cross a DMA page boundary */
-static char * get_dma_buffer(unsigned long *mem_ptr)
-{
-    char *ret;
-
-    ret = (char *) *mem_ptr;
-
-    if (!valid_dma_page(*mem_ptr, DMA_BUFF_SIZE + sizeof(struct mbuf))) {
-        *mem_ptr += (DMA_BUFF_SIZE + sizeof(struct mbuf));
-        ret = (char *) *mem_ptr;
-    }
-    *mem_ptr += (DMA_BUFF_SIZE + sizeof(struct mbuf));
-    return (ret);
-} /* get_dma_buffer() */
-
-
-/*
- * Sets up all the structures for the PT device
- */
-static int pt_probe(struct device *dev)
-{
-    short ioaddr;
-    struct pt_local *lp;
-    unsigned long flags;
-    unsigned long mem_ptr;
-
-    ioaddr = dev->base_addr;
-
-    /*
-     * Initialise the device structure.
-     * Must be done before chipset_init()
-     * Make sure data structures used by  the PT are aligned
-     */
-    dev->priv = (void *) (((int) dev->priv + 7) & ~7);
-    lp = (struct pt_local*) dev->priv;
-
-    memset(dev->priv, 0, sizeof(struct pt_local));
-
-    /* Allocate some buffers which do not cross DMA boundaries */
-    mem_ptr = (unsigned long) dev->priv + sizeof(struct pt_local);
-    lp->txdmabuf = get_dma_buffer(&mem_ptr);
-    lp->rxdmabuf1 = (struct mbuf *) get_dma_buffer(&mem_ptr);
-    lp->rxdmabuf2 = (struct mbuf *) get_dma_buffer(&mem_ptr);
-
-    /* Initialise the Rx buffer */
-    lp->rcvbuf = lp->rxdmabuf1;
-    lp->rcp = lp->rcvbuf->data;
-    lp->rcvbuf->cnt = 0;
-
-    /* Initialise the transmit queue head structure */
-    skb_queue_head_init(&lp->sndq);
-
-    lp->base = dev->base_addr;
-    lp->cardbase = dev->base_addr & 0x3f0;
-
-    /* These need to be initialised before scc_init() is called.
-     */
-    lp->xtal = XTAL;
-
-    if (dev->base_addr & CHANA) {
-        lp->speed = DEF_A_SPEED;
-        lp->txdelay = DEF_A_TXDELAY;
-        lp->persist = DEF_A_PERSIST;
-        lp->slotime = DEF_A_SLOTIME;
-        lp->squeldelay = DEF_A_SQUELDELAY;
-        lp->clockmode = DEF_A_CLOCKMODE;
-        lp->nrzi = DEF_A_NRZI;
-    } else {
-        lp->speed = DEF_B_SPEED;
-        lp->txdelay = DEF_B_TXDELAY;
-        lp->persist = DEF_B_PERSIST;
-        lp->slotime = DEF_B_SLOTIME;
-        lp->squeldelay = DEF_B_SQUELDELAY;
-        lp->clockmode = DEF_B_CLOCKMODE;
-        lp->nrzi = DEF_B_NRZI;
-    }
-    lp->bufsiz = DMA_BUFF_SIZE;
-    lp->tstate = IDLE;
-
-    chipset_init(dev);
-
-    if (dev->base_addr & CHANA) {
-        /* Note that a single IRQ services 2 devices (A and B channels)
-        */
-
-	/*
-	 * We disable the dma for a while, we have to get ints working
-	 * properly first!!
-	 */
-	lp->dmachan = 0;
-
-        if (dev->irq < 2) {
-            autoirq_setup(0);
-
-            /* Turn on PT interrupts */
-            save_flags(flags);
-            cli();
-            outb_p( pt_sercfg |= PT_EI, lp->cardbase + INT_CFG);
-            restore_flags(flags);
-
-            /* Set a timer interrupt */
-            tdelay(lp, 1);
-            dev->irq = autoirq_report(20);
-
-	    /* Turn off PT interrupts */
-	    save_flags(flags);
-	    cli();
-            outb_p( (pt_sercfg  &= ~ PT_EI), lp->cardbase + INT_CFG);
-            restore_flags(flags);
-
-            if (!dev->irq) {
-                printk(KERN_ERR "PT: ERROR: Failed to detect IRQ line, assuming IRQ7.\n");
-            }
-        }
-
-        printk(KERN_INFO "PT: Autodetected IRQ %d, assuming DMA %d\n", dev->irq, dev->dma);
-
-        /* This board has jumpered interrupts. Snarf the interrupt vector
-         * now.  There is no point in waiting since no other device can use
-         * the interrupt, and this marks the 'irqaction' as busy.
-         */
-        {
-            int irqval = request_irq(dev->irq, &pt_interrupt,0, "pt", dev);
-            if (irqval) {
-                printk(KERN_ERR "PT: ERROR: Unable to get IRQ %d (irqval = %d).\n",
-                    dev->irq, irqval);
-                return EAGAIN;
-            }
-        }
-
-        /* Grab the region */
-        request_region(ioaddr & 0x3f0, PT_TOTAL_SIZE, "pt" );
-    } /* A port */
-    dev->open = pt_open;
-    dev->stop = pt_close;
-    dev->do_ioctl = pt_ioctl;
-    dev->hard_start_xmit = pt_send_packet;
-    dev->get_stats = pt_get_stats;
-
-    /* Fill in the fields of the device structure */
-    dev_init_buffers(dev);
-
-#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE)
-    dev->hard_header    = ax25_encapsulate;
-    dev->rebuild_header = ax25_rebuild_header;
-#endif
-
-    dev->set_mac_address = pt_set_mac_address;
-
-    dev->type = ARPHRD_AX25;            /* AF_AX25 device */
-    dev->hard_header_len = 73;      /* We do digipeaters now */
-    dev->mtu = 1500;                /* eth_mtu is default */
-    dev->addr_len = 7;               /* sizeof an ax.25 address */
-    memcpy(dev->broadcast, ax25_bcast, 7);
-    memcpy(dev->dev_addr, ax25_test, 7);
-
-    /* New style flags */
-    dev->flags = 0;
-
-    return 0;
-} /* pt_probe() */
-
-
-/* Open/initialise the board.  This is called (in the current kernel)
- * sometime after booting when the 'ifconfig' program is run.
- *
- * This routine should set everything up anew at each open, even
- * registers that 'should' only be set once at boot, so that there is
- * a non-reboot way to recover if something goes wrong.
- * derived from last half of tsync_attach()
- */
-static int pt_open(struct device *dev)
-{
-    unsigned long flags;
-    struct pt_local *lp = dev->priv;
-    static first_time = 1;
-
-    if (dev->base_addr & CHANA)
-    {
-        if (first_time)
-        {
-            if (request_dma(dev->dma, "pt"))
-            {
-                free_irq(dev->irq, dev);
-                return -EAGAIN;
-            }
-        }
-
-         /* Reset hardware */
-         chipset_init(dev);
-     }
-     lp->tstate = IDLE;
-
-     if (dev->base_addr & CHANA)
-     {
-         scc_init(dev);
-         scc_init(dev->next);
-     }
-     /* Save a copy of register RR0 for comparing with later on */
-     /* We always put 0 in zero count */
-     lp->saved_RR0 = rdscc(lp->cardbase, lp->base + CTL, R0) & ~ZCOUNT;
-
-    /* master interrupt enable */
-    save_flags(flags);
-    cli();
-    wrtscc(lp->cardbase, lp->base + CTL, R9, MIE | NV);
-    outb_p( pt_sercfg |= PT_EI, lp->cardbase + INT_CFG);
-    restore_flags(flags);
-
-    lp->open_time = jiffies;
-
-    dev->tbusy = 0;
-    dev->interrupt = 0;
-    dev->start = 1;
-    first_time = 0;
-
-    MOD_INC_USE_COUNT;
-
-    return 0;
-} /* pt_open() */
-
-static int pt_send_packet(struct sk_buff *skb, struct device *dev)
-{
-	struct pt_local *lp = (struct pt_local *) dev->priv;
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_send_packet(): (%d)\n", lp->base & CHANA);
-#endif
-	hardware_send_packet(lp, skb);
-	dev->trans_start = jiffies;
-
-	return 0;
-}
-
-
-
-/* The inverse routine to pt_open() */
-static int pt_close(struct device *dev)
-{
-	unsigned long flags;
-	struct pt_local *lp = dev->priv;
-	struct sk_buff *ptr = NULL;
-	int cmd;
-
-	cmd = lp->base + CTL;
-
-	save_flags(flags);
-	cli();
-
-	/* Reset SCC or channel */
-	chipset_init(dev);
-	disable_dma(lp->dmachan);
-
-	lp->open_time = 0;
-	dev->tbusy = 1;
-	dev->start = 0;
-
-	/* Free any buffers left in the hardware transmit queue */
-	while ((ptr = skb_dequeue(&lp->sndq)) != NULL)
-		kfree_skb(ptr, FREE_WRITE);
-
-	restore_flags(flags);
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_close(): Closing down channel (%d).\n", lp->base & CHANA);
-#endif
-
-	MOD_DEC_USE_COUNT;
-
-	return 0;
-} /* pt_close() */
-
-
-static int pt_ioctl(struct device *dev, struct ifreq *ifr, int cmd)
-{
-    unsigned long flags;
-    struct pt_req rq;
-    struct pt_local *lp = (struct pt_local *) dev->priv;
-
-    int ret = verify_area(VERIFY_WRITE, ifr->ifr_data, sizeof(struct pt_req));
-    if (ret)
-	return ret;
-
-    if (cmd != SIOCDEVPRIVATE)
-        return -EINVAL;
-
-    copy_from_user(&rq, ifr->ifr_data, sizeof(struct pt_req));
-
-    switch (rq.cmd) {
-    case SIOCSPIPARAM:
-
-	if (!suser())
-	    return -EPERM;
-	save_flags(flags);
-	cli();
-	lp->txdelay = rq.txdelay;
-	lp->persist = rq.persist;
-	lp->slotime = rq.slotime;
-	lp->squeldelay = rq.squeldelay;
-	lp->clockmode = rq.clockmode;
-	lp->speed = rq.speed;
-	pt_open(&pt0a);
-	restore_flags(flags);
-	ret = 0;
-	break;
-
-    case SIOCSPIDMA:
-
-	if (!suser())
-	    return -EPERM;
-	ret = 0;
-	if (dev->base_addr & CHANA) {   /* if A channel */
-	   if (rq.dmachan < 1 || rq.dmachan > 3)
-		return -EINVAL;
-	   save_flags(flags);
-	   cli();
-	   pt_close(dev);
-	   free_dma(lp->dmachan);
-	   dev->dma = lp->dmachan = rq.dmachan;
-	   if (request_dma(lp->dmachan,"pt"))
-		ret = -EAGAIN;
-	   pt_open(dev);
-	   restore_flags(flags);
-	}
-	break;
-
-    case SIOCSPIIRQ:
-	ret = -EINVAL;      /* add this later */
-	break;
-
-    case SIOCGPIPARAM:
-    case SIOCGPIDMA:
-    case SIOCGPIIRQ:
-
-	rq.speed = lp->speed;
-	rq.txdelay = lp->txdelay;
-	rq.persist = lp->persist;
-	rq.slotime = lp->slotime;
-	rq.squeldelay = lp->squeldelay;
-	rq.clockmode = lp->clockmode;
-	rq.dmachan = lp->dmachan;
-	rq.irq = dev->irq;
-	copy_to_user(ifr->ifr_data, &rq, sizeof(struct pt_req));
-	ret = 0;
-	break;
-
-    default:
-	ret = -EINVAL;
-    }
-    return ret;
-}
-
-/*
- *	Get the current statistics.
- *	This may be called with the card open or closed. 
- */
- 
-static struct net_device_stats *pt_get_stats(struct device *dev)
-{
-	struct pt_local *lp = (struct pt_local *) dev->priv;
-	return &lp->stats;
-}
-
-
-/*
- * Local variables:
- *  compile-command: "gcc -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -m486 -c skeleton.c"
- *  version-control: t
- *  kept-new-versions: 5
- *  tab-width: 4
- * End:
- */
-
-
-static void tdelay(struct pt_local *lp, int time)
-{
-	/* For some reason, we turn off the Tx interrupts here! */
-	if (!lp->dmachan)
-		wrtscc(lp->cardbase, lp->base + CTL, R1, INT_ALL_Rx | EXT_INT_ENAB);
-
-	if (lp->base & CHANA) 
-	{
-		outb_p(time & 0xff, lp->cardbase + TMR1);
-		outb_p((time >> 8)&0xff, lp->cardbase + TMR1);
-	}
-	else
-	{
-		outb_p(time & 0xff, lp->cardbase + TMR2);
-		outb_p((time >> 8)&0xff, lp->cardbase + TMR2);
-	}
-} /* tdelay */
-
-
-static void pt_txisr(struct pt_local *lp)
-{
-	unsigned long flags;
-	int cmd;
-	unsigned char c;
-
-	save_flags(flags);
-	cli();
-	cmd = lp->base + CTL;
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_txisr(): tstate = %d (%d).\n", lp->tstate, lp->base & CHANA);
-#endif
-
-	switch (lp->tstate)
-	{
-	case CRCOUT:
-	    lp->tstate = FLAGOUT;
-	    tdelay(lp, lp->squeldelay);
-	    restore_flags(flags);
-	    return;
-
-	case IDLE:
-	    /* Transmitter idle. Find a frame for transmission */
-	    if ((lp->sndbuf = skb_dequeue(&lp->sndq)) == NULL)
-	    {
-	        /* Nothing to send - return to receive mode
-	         * Tx off now - flag should have gone
-	         */
-	        pt_rts(lp, OFF);
-
-	        restore_flags(flags);
-	        return;
-	    }
-	    if (!lp->dmachan)
-	    {
-		    lp->txptr = lp->sndbuf->data;
-		    lp->txptr++;		/* Ignore KISS control byte */
-		    lp->txcnt = (int) lp->sndbuf->len - 1;
-		}
-	    /* If a buffer to send, drop though here */
-
-	case DEFER:
-	    /* Check DCD - debounce it */
-	    /* See Intel Microcommunications Handbook p2-308 */
-	    wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
-	    wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
-	    if ((rdscc(lp->cardbase, cmd, R0) & DCD) != 0)
-	    {
-	        lp->tstate = DEFER;
-	        tdelay(lp, 100);
-	        /* DEFER until DCD transition or timeout */
-	        wrtscc(lp->cardbase, cmd, R15, DCDIE);
-	        restore_flags(flags);
-	        return;
-	    }
-	    if (random() > lp->persist)
-	    {
-	        lp->tstate = DEFER;
-	        tdelay(lp, lp->slotime);
-	        restore_flags(flags);
-	        return;
-	    }
-	    pt_rts(lp, ON);		/* Tx on */
-	    if (lp->dmachan)
-	    	wrtscc(lp->cardbase, cmd, R5, TxCRC_ENAB | RTS | Tx8);
-	    lp->tstate = ST_TXDELAY;
-	    tdelay(lp, lp->txdelay);
-	    restore_flags(flags);
-	    return;
-
-	case ACTIVE:
-	    /* Here we are actively sending a frame */
-	    if (lp->txcnt--)
-	    {
-	        /* XLZ - checkout Gracilis PT code to see if the while
-	         * loop is better or not.
-	         */
-	        c = *lp->txptr++;
-	        /* next char is gone */
-	        wrtscc(lp->cardbase, cmd, R8, c);
-	        /* stuffing a char satisfies interrupt condition */
-	    } else {
-	        /* No more to send */
-	        kfree_skb(lp->sndbuf, FREE_WRITE);
-	        lp->sndbuf = NULL;
-	        if ((rdscc(lp->cardbase, cmd, R0) & TxEOM))
-	        {
-	            /* Did we underrun */
-	            lp->stats.tx_errors++;
-	            lp->stats.tx_fifo_errors++;
-	            wrtscc(lp->cardbase, cmd, R0, SEND_ABORT);
-	            lp->tstate = FLAGOUT;
-	            tdelay(lp, lp->squeldelay);
-	            restore_flags(flags);
-	            return;
-	        }
-	        lp->tstate = UNDERRUN;
-	        /* Send flags on underrun */
-	       if (lp->nrzi)
-	       {
-	           wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZI);
-	       } else {
-	           wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZ);
-	       }
-	       /* Reset Tx interrupt pending */
-	       wrtscc(lp->cardbase, cmd, R0, RES_Tx_P);
-	   }
-	   restore_flags(flags);
-	   return;
-	default:
-		printk(KERN_ERR "PT: pt_txisr(): Invalid tstate (%d) for chan %s.\n", lp->tstate, (cmd & CHANA? "A": "B") );
-		pt_rts(lp, OFF);
-		lp->tstate = IDLE;
-		break;
-    } 				/*switch */
-    restore_flags(flags);
-}
-
-static void pt_rxisr(struct device *dev)
-{
-    struct pt_local *lp = (struct pt_local*) dev->priv;
-    int cmd = lp->base + CTL;
-    int bytecount;
-    unsigned long flags;
-    char rse;
-    struct sk_buff *skb;
-    int sksize, pkt_len;
-    struct mbuf *cur_buf = NULL;
-    unsigned char *cfix;
-
-    save_flags(flags);
-    cli();
-
-    /* Get status byte from R1 */
-    rse = rdscc(lp->cardbase, cmd, R1);
-
-#ifdef PT_DEBUG
-    printk(KERN_DEBUG "PT: pt_rxisr(): R1 = %#3x. (%d)\n", rse, lp->base & CHANA);
-#endif
-
-	if (lp->dmachan && (rse & Rx_OVR))
-		lp->rstate = RXERROR;
-
-    if (rdscc(lp->cardbase, cmd, R0) & Rx_CH_AV && !lp->dmachan)
-    {
-        /* There is a char to be stored
-         * Read special condition bits before reading the data char
-         */
-        if (rse & Rx_OVR)
-        {
-             /* Rx overrun - toss buffer */
-             /* wind back the pointers */
-             lp->rcp = lp->rcvbuf->data;
-             lp->rcvbuf->cnt = 0;
-             lp->rstate = RXERROR;
-             lp->stats.rx_errors++;
-             lp->stats.rx_fifo_errors++;
-         } else if (lp->rcvbuf->cnt >= lp->bufsiz)
-             {
-                 /* Too large packet
-                  * wind back Rx buffer pointers
-                  */
-                 lp->rcp = lp->rcvbuf->data;
-                 lp->rcvbuf->cnt = 0;
-                 lp->rstate = TOOBIG;
-             }
-         /* ok, we can store the Rx char if no errors */
-         if (lp->rstate == ACTIVE)
-         {
-             *lp->rcp++ = rdscc(lp->cardbase, cmd, R8);
-             lp->rcvbuf->cnt++;
-         } else {
-             /* we got an error, dump the FIFO */
-             (void) rdscc(lp->cardbase, cmd, R8);
-             (void) rdscc(lp->cardbase, cmd, R8);
-             (void) rdscc(lp->cardbase, cmd, R8);
-
-             /* Reset error latch */
-             wrtscc(lp->cardbase, cmd, R0, ERR_RES);
-             lp->rstate = ACTIVE;
-
-             /* Resync the SCC */
-             wrtscc(lp->cardbase, cmd, R3, RxENABLE | ENT_HM | AUTO_ENAB | Rx8);
-
-         }
-     }
-
-     if (rse & END_FR)
-     {
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_rxisr() Got end of a %u byte frame.\n", lp->rcvbuf->cnt);
-#endif
-		if (lp->dmachan)
-		{
-			clear_dma_ff(lp->dmachan);
-			bytecount = lp->bufsiz - get_dma_residue(lp->dmachan);
-		} else {
-			bytecount = lp->rcvbuf->cnt;
-		}
-
-         /* END OF FRAME - Make sure Rx was active */
-         if (lp->rcvbuf->cnt > 0 || lp->dmachan)
-         {
-             if ((rse & CRC_ERR) || (lp->rstate > ACTIVE) || (bytecount < 10))
-             {
-                 if ((bytecount >= 10) && (rse & CRC_ERR))
-                 {
-                     lp->stats.rx_crc_errors++;
-                 }
-                 if (lp->dmachan)
-                 {
-                 	if (lp->rstate == RXERROR)
-                 	{
-                 		lp->stats.rx_errors++;
-                 		lp->stats.rx_over_errors++;
-                 	}
-                 	lp->rstate = ACTIVE;
-                 	setup_rx_dma(lp);
-                 } else {
-	                 /* wind back Rx buffer pointers */
-    	             lp->rcp = lp->rcvbuf->data;
-        	         lp->rcvbuf->cnt = 0;
-
-					/* Re-sync the SCC */
-					wrtscc(lp->cardbase, cmd, R3, RxENABLE | ENT_HM | AUTO_ENAB | Rx8);
-
-        	     }
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_rxisr() %s error.\n", (rse & CRC_ERR)? "CRC" : "state");
-#endif
-             } else {
-                 /* We have a valid frame */
-                 if (lp->dmachan)
-                 {
-                 	pkt_len = lp->rcvbuf->cnt = bytecount - 2 +1;
-					/* Get buffer for next frame */
-                 	cur_buf = lp->rcvbuf;
-                 	switchbuffers(lp);
-                 	setup_rx_dma(lp);
-                 } else {
-	                 pkt_len = lp->rcvbuf->cnt -= 2;  /* Toss 2 CRC bytes */
-    	             pkt_len += 1;	/* make room for KISS control byte */
-        		}
-
-                 /* Malloc up new buffer */
-                 sksize = pkt_len;
-                 skb = dev_alloc_skb(sksize);
-                 if (skb == NULL)
-                 {
-                     printk(KERN_ERR "PT: %s: Memory squeeze, dropping packet.\n", dev->name);
-                     lp->stats.rx_dropped++;
-                     restore_flags(flags);
-                     return;
-                 }
-                 skb->dev = dev;
-
-                 /* KISS kludge = prefix with a 0 byte */
-                 cfix=skb_put(skb,pkt_len);
-                 *cfix++=0;
-                 /* skb->data points to the start of sk_buff area */
-                 if (lp->dmachan)
-                 	memcpy(cfix, (char*)cur_buf->data, pkt_len - 1);
-                 else
-                    memcpy(cfix, lp->rcvbuf->data, pkt_len - 1);
-                 skb->protocol = ntohs(ETH_P_AX25);
-                 skb->mac.raw=skb->data;
-                 lp->stats.rx_bytes+=skb->len;
-                 netif_rx(skb);
-                 lp->stats.rx_packets++;
-                 if (!lp->dmachan)
-                 {
-	                 /* packet queued - wind back buffer for next frame */
-    	             lp->rcp = lp->rcvbuf->data;
-	                 lp->rcvbuf->cnt = 0;
-	             }
-             } /* good frame */
-         } /* check active Rx */
-         /* Clear error status */
-         lp->rstate = ACTIVE;
-         /* Reset error latch */
-     } /* end EOF check */
-     wrtscc(lp->cardbase, cmd, R0, ERR_RES);
-     restore_flags(flags);
-} /* pt_rxisr() */
-
-/*
- * This handles the two timer interrupts.
- * This is a real bugger, cause you have to rip it out of the pi's
- * external status code.  They use the CTS line or something.
- */
-static void pt_tmrisr(struct pt_local *lp)
-{
-    unsigned long flags;
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: pt_tmrisr(): tstate = %d (%d).\n", lp->tstate, lp->base & CHANA);
-#endif
-
-    save_flags(flags);
-    cli();
-
-
-    switch (lp->tstate)
-    {
-    /* Most of this stuff is in pt_exisr() */
-    case FLAGOUT:
-    case ST_TXDELAY:
-    case DEFER:
-/*    case ACTIVE:
-    case UNDERRUN:*/
-        pt_exisr(lp);
-        break;
-
-    default:
-	if (lp->base & CHANA)
- 	    printk(KERN_ERR "PT: pt_tmrisr(): Invalid tstate %d for Channel A\n", lp->tstate);
-	else
-	    printk(KERN_ERR "PT: pt_tmrisr(): Invalid tstate %d for Channel B\n", lp->tstate);
-	break;
-    } /* end switch */
-    restore_flags(flags);
-} /* pt_tmrisr() */
-
-
-/*
- * This routine is called by the kernel when there is an interrupt for the
- * PT.
- */
-static void pt_interrupt(int irq, void *dev_id, struct pt_regs *regs)
-{
-    /* It's a tad dodgy here, but we assume pt0a until proven otherwise */
-    struct device *dev = &pt0a;
-    struct pt_local *lp = dev->priv;
-    unsigned char intreg;
-    unsigned char st;
-    register int cbase = dev->base_addr & 0x3f0;
-    unsigned long flags;
-
-    /* Read the PT's interrupt register, this is not the SCC one! */
-    intreg = inb_p(cbase + INT_REG);
-    while(( intreg & 0x07) != 0x07) {
-        /* Read interrupt register pending from Channel A */
-        while ((st = rdscc(cbase, cbase + CHANA + CTL, R3)) != 0)
-        {
-        	/* Read interrupt vector from R2, channel B */
-#ifdef PT_DEBUG
-		printk(KERN_DEBUG "PT: pt_interrupt(): R3 = %#3x", st);
-#endif
-/*        	st = rdscc(lp->cardbase, cbase + CHANB + CTL, R2) & 0x0e;*/
-#ifdef PT_DEBUG
-		printk(KERN_DEBUG "PI: R2 = %#3x.\n", st);
-#endif
-			if (st & CHARxIP) {
-			    /* Channel A Rx */
-	            lp = (struct pt_local*)pt0a.priv;
-	            pt_rxisr(&pt0a);
-	        } else if (st & CHATxIP) {
-	            /* Channel A Tx */
-	            lp = (struct pt_local*)pt0a.priv;
-	            pt_txisr(lp);
-	        } else if (st & CHAEXT) {
-	        	/* Channel A External Status */
-	        	lp = (struct pt_local*)pt0a.priv;
-	        	pt_exisr(lp);
-	        } else if (st & CHBRxIP) {
-	        	/* Channel B Rx */
-	            lp= (struct pt_local*)pt0b.priv;
-	            pt_rxisr(&pt0b);
-	        } else if (st & CHBTxIP) {
-            	/* Channel B Tx */
-	            lp = (struct pt_local*)pt0b.priv;
-	            pt_txisr(lp);
-			} else if (st & CHBEXT) {
-	        	/* Channel B External Status */
-	        	lp = (struct pt_local*)pt0b.priv;
-	        	pt_exisr(lp);
-	        }
-            /* Reset highest interrupt under service */
-            save_flags(flags);
-            cli();
-            wrtscc(lp->cardbase, lp->base + CTL, R0, RES_H_IUS);
-            restore_flags(flags);
-        }  /* end of SCC ints */
-
-        if (!(intreg & PT_TMR1_MSK))
-        {
-            /* Clear timer 1 */
-            inb_p(cbase + TMR1CLR);
-
-            pt_tmrisr( (struct pt_local*)pt0a.priv);
-        }
-
-        if (!(intreg & PT_TMR2_MSK))
-        {
-            /* Clear timer 2 */
-            inb_p(cbase + TMR2CLR);
-
-            pt_tmrisr( (struct pt_local*)pt0b.priv);
-        }
-
-        /* Get the next PT interrupt vector */
-        intreg = inb_p(cbase + INT_REG);
-    } /* while (intreg) */
-} /* pt_interrupt() */
-
-
-static void pt_exisr(struct pt_local *lp)
-{
-    unsigned long flags;
-    int cmd = lp->base + CTL;
-    unsigned char st;
-    char c;
-    int length;
-
-    save_flags(flags);
-    cli();
-
-    /* Get external status */
-    st = rdscc(lp->cardbase, cmd, R0);
-
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: exisr(): R0 = %#3x tstate = %d (%d).\n", st, lp->tstate, lp->base & CHANA);
-#endif
-    /* Reset external status latch */
-    wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
-
-    if ((lp->rstate >= ACTIVE) && (st & BRK_ABRT) && lp->dmachan)
-    {
-    	setup_rx_dma(lp);
-    	lp->rstate = ACTIVE;
-    }
-
-    switch (lp->tstate)
-    {
-    case ACTIVE:		/* Unexpected underrun */
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: exisr(): unexpected underrun detected.\n");
-#endif
-        kfree_skb(lp->sndbuf, FREE_WRITE);
-        lp->sndbuf = NULL;
-        if (!lp->dmachan)
-        {
-	        wrtscc(lp->cardbase, cmd, R0, SEND_ABORT);
-	        lp->stats.tx_errors++;
-	        lp->stats.tx_fifo_errors++;
-	    }
-        lp->tstate = FLAGOUT;
-        tdelay(lp, lp->squeldelay);
-        restore_flags(flags);
-        return;
-    case UNDERRUN:
-        lp->tstate = CRCOUT;
-        restore_flags(flags);
-        return;
-    case FLAGOUT:
-        /* squeldelay has timed out */
-        /* Find a frame for transmission */
-        if ((lp->sndbuf = skb_dequeue(&lp->sndq)) == NULL)
-        {
-            /* Nothing to send - return to Rx mode */
-            pt_rts(lp, OFF);
-            lp->tstate = IDLE;
-            restore_flags(flags);
-            return;
-        }
-        if (!lp->dmachan)
-        {
-	        lp->txptr = lp->sndbuf->data;
-    	    lp->txptr++;		/* Ignore KISS control byte */
-	        lp->txcnt = (int) lp->sndbuf->len - 1;
-	    }
-        /* Fall through if we have a packet */
-
-    case ST_TXDELAY:
-    	if (lp->dmachan)
-    	{
-    		/* Disable DMA chan */
-    		disable_dma(lp->dmachan);
-
-    		/* Set up for TX dma */
-    		wrtscc(lp->cardbase, cmd, R1, WT_FN_RDYFN | EXT_INT_ENAB);
-
-    		length = lp->sndbuf->len - 1;
-    		memcpy(lp->txdmabuf, &lp->sndbuf->data[1], length);
-
-    		/* Setup DMA controller for Tx */
-    		setup_tx_dma(lp, length);
-
-    		enable_dma(lp->dmachan);
-
-    		/* Reset CRC, Txint pending */
-    		wrtscc(lp->cardbase, cmd, R0, RES_Tx_CRC | RES_Tx_P);
-
-    		/* Allow underrun only */
-    		wrtscc(lp->cardbase, cmd, R15, TxUIE);
-
-    		/* Enable TX DMA */
-    		wrtscc(lp->cardbase, cmd, R1, WT_RDY_ENAB | WT_FN_RDYFN | EXT_INT_ENAB);
-
-    		/* Send CRC on underrun */
-    		wrtscc(lp->cardbase, cmd, R0, RES_EOM_L);
-
-    		lp->tstate = ACTIVE;
-    		break;
-    	}
-        /* Get first char to send */
-        lp->txcnt--;
-        c = *lp->txptr++;
-        /* Reset CRC for next frame */
-        wrtscc(lp->cardbase, cmd, R0, RES_Tx_CRC);
-
-        /* send abort on underrun */
-        if (lp->nrzi)
-        {
-            wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZI | ABUNDER);
-        } else {
-            wrtscc(lp->cardbase, cmd, R10, CRCPS | NRZ | ABUNDER);
-        }
-        /* send first char */
-        wrtscc(lp->cardbase, cmd, R8, c);
-
-        /* Reset end of message latch */
-        wrtscc(lp->cardbase, cmd, R0, RES_EOM_L);
-
-        /* stuff an extra one in */
-/*        while ((rdscc(lp->cardbase, cmd, R0) & Tx_BUF_EMP) && lp->txcnt)
-        {
-            lp->txcnt--;
-            c = *lp->txptr++;
-            wrtscc(lp->cardbase, cmd, R8, c);
-        }*/
-
-        /* select Tx interrupts to enable */
-        /* Allow underrun int only */
-        wrtscc(lp->cardbase, cmd, R15, TxUIE);
-
-        /* Reset external interrupts */
-        wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
-
-        /* Tx and Rx ints enabled */
-        wrtscc(lp->cardbase, cmd, R1, TxINT_ENAB | EXT_INT_ENAB);
-
-        lp->tstate = ACTIVE;
-        restore_flags(flags);
-        return;
-
-        /* slotime has timed out */
-    case DEFER:
-        /* Check DCD - debounce it
-         * see Intel Microcommunications Handbook, p2-308
-         */
-        wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
-        wrtscc(lp->cardbase, cmd, R0, RES_EXT_INT);
-        if ((rdscc(lp->cardbase, cmd, R0) & DCD) != 0)
-        {
-            lp->tstate = DEFER;
-            tdelay(lp, 100);
-            /* DEFER until DCD transition or timeout */
-            wrtscc(lp->cardbase, cmd, R15, DCDIE);
-            restore_flags(flags);
-            return;
-        }
-        if (random() > lp->persist)
-        {
-            lp->tstate = DEFER;
-            tdelay(lp, lp->slotime);
-            restore_flags(flags);
-            return;
-        }
-        if (lp->dmachan)
-        	wrtscc(lp->cardbase, cmd, R5, TxCRC_ENAB | RTS | Tx8);
-        pt_rts(lp, ON);			/* Tx on */
-        lp->tstate = ST_TXDELAY;
-        tdelay(lp, lp->txdelay);
-        restore_flags(flags);
-        return;
-
- 	/* Only for int driven parts */
- 	if (lp->dmachan)
- 	{
- 		restore_flags(flags);
- 		return;
- 	}
-
-    } /* end switch */
-    /*
-     * Rx mode only
-     * This triggers when hunt mode is entered, & since an ABORT
-     * automatically enters hunt mode, we use that to clean up
-     * any waiting garbage
-     */
-    if ((lp->rstate == ACTIVE) && (st & BRK_ABRT) )
-    {
-#ifdef PT_DEBUG
-	printk(KERN_DEBUG "PT: exisr(): abort detected.\n");
-#endif
-  		/* read and dump all of SCC Rx FIFO */
-        (void) rdscc(lp->cardbase, cmd, R8);
-        (void) rdscc(lp->cardbase, cmd, R8);
-        (void) rdscc(lp->cardbase, cmd, R8);
-
-        lp->rcp = lp->rcvbuf->data;
-        lp->rcvbuf->cnt = 0;
-
-		/* Re-sync the SCC */
-		wrtscc(lp->cardbase, cmd, R3, RxENABLE | ENT_HM | AUTO_ENAB | Rx8);
-
-    }
-
-    /* Check for DCD transitions */
-    if ( (st & DCD) != (lp->saved_RR0 & DCD))
-    {
-#ifdef PT_DEBUG
-        printk(KERN_DEBUG "PT: pt_exisr(): DCD is now %s.\n", (st & DCD)? "ON" : "OFF" );
-#endif
-		if (st & DCD)
-		{
-			/* Check that we don't already have some data */
-			if (lp->rcvbuf->cnt > 0)
-			{
-#ifdef PT_DEBUG
-				printk(KERN_DEBUG "PT: pt_exisr() dumping %u bytes from buffer.\n", lp->rcvbuf->cnt);
-#endif
-				/* wind back buffers */
-				lp->rcp = lp->rcvbuf->data;
-				lp->rcvbuf->cnt = 0;
-			}
-		} else {  /* DCD off */
-
-			/* read and dump al SCC FIFO */
-			(void)rdscc(lp->cardbase, cmd, R8);
-			(void)rdscc(lp->cardbase, cmd, R8);
-			(void)rdscc(lp->cardbase, cmd, R8);
-
-			/* wind back buffers */
-			lp->rcp = lp->rcvbuf->data;
-			lp->rcvbuf->cnt = 0;
-
-			/* Re-sync the SCC */
-			wrtscc(lp->cardbase, cmd, R3, RxENABLE | ENT_HM | AUTO_ENAB | Rx8);
-		}
-
-    }
-    /* Update the saved version of register RR) */
-    lp->saved_RR0 = st &~ ZCOUNT;
-    restore_flags(flags);
-
-} /* pt_exisr() */
-
-#ifdef MODULE
-EXPORT_NO_SYMBOLS;
-
-MODULE_AUTHOR("Craig Small VK2XLZ <vk2xlz@vk2xlz.ampr.org>");
-MODULE_DESCRIPTION("AX.25 driver for the Gracillis PacketTwin HDLC card");
-
-int init_module(void)
-{
-	return pt_init();
-}
-
-void cleanup_module(void)
-{
-	free_irq(pt0a.irq, &pt0a);	/* IRQs and IO Ports are shared */
-	release_region(pt0a.base_addr & 0x3f0, PT_TOTAL_SIZE);
-
-	kfree(pt0a.priv);
-	pt0a.priv = NULL;
-	unregister_netdev(&pt0a);
-
-	kfree(pt0b.priv);
-	pt0b.priv = NULL;
-	unregister_netdev(&pt0b);
-}
-#endif

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TCL-scripts by Sam Shen, slshen@lbl.gov