Initial import

1 files changed, 1290 insertions, 0 deletions

diff --git a/drivers/net/hamradio/baycom_epp.c b/drivers/net/hamradio/baycom_epp.c
new file mode 100644
index 000000000..83c7cce0d
--- /dev/null
+++ b/drivers/net/hamradio/baycom_epp.c
@@ -0,0 +1,1290 @@
+/*****************************************************************************/
+
+/*
+ *	baycom_epp.c  -- baycom epp radio modem driver.
+ *
+ *	Copyright (C) 1998-2000
+ *          Thomas Sailer (sailer@ife.ee.ethz.ch)
+ *
+ *	This program is free software; you can redistribute it and/or modify
+ *	it under the terms of the GNU General Public License as published by
+ *	the Free Software Foundation; either version 2 of the License, or
+ *	(at your option) any later version.
+ *
+ *	This program is distributed in the hope that it will be useful,
+ *	but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *	GNU General Public License for more details.
+ *
+ *	You should have received a copy of the GNU General Public License
+ *	along with this program; if not, write to the Free Software
+ *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *  Please note that the GPL allows you to use the driver, NOT the radio.
+ *  In order to use the radio, you need a license from the communications
+ *  authority of your country.
+ *
+ *
+ *  History:
+ *   0.1  xx.xx.1998  Initial version by Matthias Welwarsky (dg2fef)
+ *   0.2  21.04.1998  Massive rework by Thomas Sailer
+ *                    Integrated FPGA EPP modem configuration routines
+ *   0.3  11.05.1998  Took FPGA config out and moved it into a separate program
+ *   0.4  26.07.1999  Adapted to new lowlevel parport driver interface
+ *   0.5  03.08.1999  adapt to Linus' new __setup/__initcall
+ *                    removed some pre-2.2 kernel compatibility cruft
+ *   0.6  10.08.1999  Check if parport can do SPP and is safe to access during interrupt contexts
+ *   0.7  12.02.2000  adapted to softnet driver interface
+ *
+ */
+
+/*****************************************************************************/
+
+#include <linux/crc-ccitt.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/workqueue.h>
+#include <linux/fs.h>
+#include <linux/parport.h>
+#include <linux/if_arp.h>
+#include <linux/hdlcdrv.h>
+#include <linux/baycom.h>
+#include <linux/jiffies.h>
+#include <linux/random.h>
+#include <net/ax25.h> 
+#include <asm/uaccess.h>
+
+/* --------------------------------------------------------------------- */
+
+#define BAYCOM_DEBUG
+#define BAYCOM_MAGIC 19730510
+
+/* --------------------------------------------------------------------- */
+
+static const char paranoia_str[] = KERN_ERR 
+	"baycom_epp: bad magic number for hdlcdrv_state struct in routine %s\n";
+
+static const char bc_drvname[] = "baycom_epp";
+static const char bc_drvinfo[] = KERN_INFO "baycom_epp: (C) 1998-2000 Thomas Sailer, HB9JNX/AE4WA\n"
+"baycom_epp: version 0.7\n";
+
+/* --------------------------------------------------------------------- */
+
+#define NR_PORTS 4
+
+static struct net_device *baycom_device[NR_PORTS];
+
+/* --------------------------------------------------------------------- */
+
+/* EPP status register */
+#define EPP_DCDBIT      0x80
+#define EPP_PTTBIT      0x08
+#define EPP_NREF        0x01
+#define EPP_NRAEF       0x02
+#define EPP_NRHF        0x04
+#define EPP_NTHF        0x20
+#define EPP_NTAEF       0x10
+#define EPP_NTEF        EPP_PTTBIT
+
+/* EPP control register */
+#define EPP_TX_FIFO_ENABLE 0x10
+#define EPP_RX_FIFO_ENABLE 0x08
+#define EPP_MODEM_ENABLE   0x20
+#define EPP_LEDS           0xC0
+#define EPP_IRQ_ENABLE     0x10
+
+/* LPT registers */
+#define LPTREG_ECONTROL       0x402
+#define LPTREG_CONFIGB        0x401
+#define LPTREG_CONFIGA        0x400
+#define LPTREG_EPPDATA        0x004
+#define LPTREG_EPPADDR        0x003
+#define LPTREG_CONTROL        0x002
+#define LPTREG_STATUS         0x001
+#define LPTREG_DATA           0x000
+
+/* LPT control register */
+#define LPTCTRL_PROGRAM       0x04   /* 0 to reprogram */
+#define LPTCTRL_WRITE         0x01
+#define LPTCTRL_ADDRSTB       0x08
+#define LPTCTRL_DATASTB       0x02
+#define LPTCTRL_INTEN         0x10
+
+/* LPT status register */
+#define LPTSTAT_SHIFT_NINTR   6
+#define LPTSTAT_WAIT          0x80
+#define LPTSTAT_NINTR         (1<<LPTSTAT_SHIFT_NINTR)
+#define LPTSTAT_PE            0x20
+#define LPTSTAT_DONE          0x10
+#define LPTSTAT_NERROR        0x08
+#define LPTSTAT_EPPTIMEOUT    0x01
+
+/* LPT data register */
+#define LPTDATA_SHIFT_TDI     0
+#define LPTDATA_SHIFT_TMS     2
+#define LPTDATA_TDI           (1<<LPTDATA_SHIFT_TDI)
+#define LPTDATA_TCK           0x02
+#define LPTDATA_TMS           (1<<LPTDATA_SHIFT_TMS)
+#define LPTDATA_INITBIAS      0x80
+
+
+/* EPP modem config/status bits */
+#define EPP_DCDBIT            0x80
+#define EPP_PTTBIT            0x08
+#define EPP_RXEBIT            0x01
+#define EPP_RXAEBIT           0x02
+#define EPP_RXHFULL           0x04
+
+#define EPP_NTHF              0x20
+#define EPP_NTAEF             0x10
+#define EPP_NTEF              EPP_PTTBIT
+
+#define EPP_TX_FIFO_ENABLE    0x10
+#define EPP_RX_FIFO_ENABLE    0x08
+#define EPP_MODEM_ENABLE      0x20
+#define EPP_LEDS              0xC0
+#define EPP_IRQ_ENABLE        0x10
+
+/* Xilinx 4k JTAG instructions */
+#define XC4K_IRLENGTH   3
+#define XC4K_EXTEST     0
+#define XC4K_PRELOAD    1
+#define XC4K_CONFIGURE  5
+#define XC4K_BYPASS     7
+
+#define EPP_CONVENTIONAL  0
+#define EPP_FPGA          1
+#define EPP_FPGAEXTSTATUS 2
+
+#define TXBUFFER_SIZE     ((HDLCDRV_MAXFLEN*6/5)+8)
+
+/* ---------------------------------------------------------------------- */
+/*
+ * Information that need to be kept for each board.
+ */
+
+struct baycom_state {
+	int magic;
+
+        struct pardevice *pdev;
+	struct net_device *dev;
+	unsigned int work_running;
+	struct delayed_work run_work;
+	unsigned int modem;
+	unsigned int bitrate;
+	unsigned char stat;
+
+	struct {
+		unsigned int intclk;
+		unsigned int fclk;
+		unsigned int bps;
+		unsigned int extmodem;
+		unsigned int loopback;
+	} cfg;
+
+        struct hdlcdrv_channel_params ch_params;
+
+        struct {
+		unsigned int bitbuf, bitstream, numbits, state;
+		unsigned char *bufptr;
+		int bufcnt;
+		unsigned char buf[TXBUFFER_SIZE];
+        } hdlcrx;
+
+        struct {
+		int calibrate;
+                int slotcnt;
+		int flags;
+		enum { tx_idle = 0, tx_keyup, tx_data, tx_tail } state;
+		unsigned char *bufptr;
+		int bufcnt;
+		unsigned char buf[TXBUFFER_SIZE];
+        } hdlctx;
+
+	unsigned int ptt_keyed;
+	struct sk_buff *skb;  /* next transmit packet  */
+
+#ifdef BAYCOM_DEBUG
+	struct debug_vals {
+		unsigned long last_jiffies;
+		unsigned cur_intcnt;
+		unsigned last_intcnt;
+		int cur_pllcorr;
+		int last_pllcorr;
+		unsigned int mod_cycles;
+		unsigned int demod_cycles;
+	} debug_vals;
+#endif /* BAYCOM_DEBUG */
+};
+
+/* --------------------------------------------------------------------- */
+
+#define KISS_VERBOSE
+
+/* --------------------------------------------------------------------- */
+
+#define PARAM_TXDELAY   1
+#define PARAM_PERSIST   2
+#define PARAM_SLOTTIME  3
+#define PARAM_TXTAIL    4
+#define PARAM_FULLDUP   5
+#define PARAM_HARDWARE  6
+#define PARAM_RETURN    255
+
+/* --------------------------------------------------------------------- */
+/*
+ * the CRC routines are stolen from WAMPES
+ * by Dieter Deyke
+ */
+
+
+/*---------------------------------------------------------------------------*/
+
+#if 0
+static inline void append_crc_ccitt(unsigned char *buffer, int len)
+{
+ 	unsigned int crc = 0xffff;
+
+	for (;len>0;len--)
+		crc = (crc >> 8) ^ crc_ccitt_table[(crc ^ *buffer++) & 0xff];
+	crc ^= 0xffff;
+	*buffer++ = crc;
+	*buffer++ = crc >> 8;
+}
+#endif
+
+/*---------------------------------------------------------------------------*/
+
+static inline int check_crc_ccitt(const unsigned char *buf, int cnt)
+{
+	return (crc_ccitt(0xffff, buf, cnt) & 0xffff) == 0xf0b8;
+}
+
+/*---------------------------------------------------------------------------*/
+
+static inline int calc_crc_ccitt(const unsigned char *buf, int cnt)
+{
+	return (crc_ccitt(0xffff, buf, cnt) ^ 0xffff) & 0xffff;
+}
+
+/* ---------------------------------------------------------------------- */
+
+#define tenms_to_flags(bc,tenms) ((tenms * bc->bitrate) / 800)
+
+/* --------------------------------------------------------------------- */
+
+static inline void baycom_int_freq(struct baycom_state *bc)
+{
+#ifdef BAYCOM_DEBUG
+	unsigned long cur_jiffies = jiffies;
+	/*
+	 * measure the interrupt frequency
+	 */
+	bc->debug_vals.cur_intcnt++;
+	if (time_after_eq(cur_jiffies, bc->debug_vals.last_jiffies + HZ)) {
+		bc->debug_vals.last_jiffies = cur_jiffies;
+		bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
+		bc->debug_vals.cur_intcnt = 0;
+		bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
+		bc->debug_vals.cur_pllcorr = 0;
+	}
+#endif /* BAYCOM_DEBUG */
+}
+
+/* ---------------------------------------------------------------------- */
+/*
+ *    eppconfig_path should be setable  via /proc/sys.
+ */
+
+static char eppconfig_path[256] = "/usr/sbin/eppfpga";
+
+static char *envp[] = { "HOME=/", "TERM=linux", "PATH=/usr/bin:/bin", NULL };
+
+/* eppconfig: called during ifconfig up to configure the modem */
+static int eppconfig(struct baycom_state *bc)
+{
+	char modearg[256];
+	char portarg[16];
+        char *argv[] = { eppconfig_path, "-s", "-p", portarg, "-m", modearg,
+			 NULL };
+
+	/* set up arguments */
+	sprintf(modearg, "%sclk,%smodem,fclk=%d,bps=%d,divider=%d%s,extstat",
+		bc->cfg.intclk ? "int" : "ext",
+		bc->cfg.extmodem ? "ext" : "int", bc->cfg.fclk, bc->cfg.bps,
+		(bc->cfg.fclk + 8 * bc->cfg.bps) / (16 * bc->cfg.bps),
+		bc->cfg.loopback ? ",loopback" : "");
+	sprintf(portarg, "%ld", bc->pdev->port->base);
+	printk(KERN_DEBUG "%s: %s -s -p %s -m %s\n", bc_drvname, eppconfig_path, portarg, modearg);
+
+	return call_usermodehelper(eppconfig_path, argv, envp, UMH_WAIT_PROC);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static inline void do_kiss_params(struct baycom_state *bc,
+				  unsigned char *data, unsigned long len)
+{
+
+#ifdef KISS_VERBOSE
+#define PKP(a,b) printk(KERN_INFO "baycomm_epp: channel params: " a "\n", b)
+#else /* KISS_VERBOSE */	      
+#define PKP(a,b) 
+#endif /* KISS_VERBOSE */	      
+
+	if (len < 2)
+		return;
+	switch(data[0]) {
+	case PARAM_TXDELAY:
+		bc->ch_params.tx_delay = data[1];
+		PKP("TX delay = %ums", 10 * bc->ch_params.tx_delay);
+		break;
+	case PARAM_PERSIST:   
+		bc->ch_params.ppersist = data[1];
+		PKP("p persistence = %u", bc->ch_params.ppersist);
+		break;
+	case PARAM_SLOTTIME:  
+		bc->ch_params.slottime = data[1];
+		PKP("slot time = %ums", bc->ch_params.slottime);
+		break;
+	case PARAM_TXTAIL:    
+		bc->ch_params.tx_tail = data[1];
+		PKP("TX tail = %ums", bc->ch_params.tx_tail);
+		break;
+	case PARAM_FULLDUP:   
+		bc->ch_params.fulldup = !!data[1];
+		PKP("%s duplex", bc->ch_params.fulldup ? "full" : "half");
+		break;
+	default:
+		break;
+	}
+#undef PKP
+}
+
+/* --------------------------------------------------------------------- */
+
+static void encode_hdlc(struct baycom_state *bc)
+{
+	struct sk_buff *skb;
+	unsigned char *wp, *bp;
+	int pkt_len;
+        unsigned bitstream, notbitstream, bitbuf, numbit, crc;
+	unsigned char crcarr[2];
+	int j;
+	
+	if (bc->hdlctx.bufcnt > 0)
+		return;
+	skb = bc->skb;
+	if (!skb)
+		return;
+	bc->skb = NULL;
+	pkt_len = skb->len-1; /* strip KISS byte */
+	wp = bc->hdlctx.buf;
+	bp = skb->data+1;
+	crc = calc_crc_ccitt(bp, pkt_len);
+	crcarr[0] = crc;
+	crcarr[1] = crc >> 8;
+	*wp++ = 0x7e;
+	bitstream = bitbuf = numbit = 0;
+	while (pkt_len > -2) {
+		bitstream >>= 8;
+		bitstream |= ((unsigned int)*bp) << 8;
+		bitbuf |= ((unsigned int)*bp) << numbit;
+		notbitstream = ~bitstream;
+		bp++;
+		pkt_len--;
+		if (!pkt_len)
+			bp = crcarr;
+		for (j = 0; j < 8; j++)
+			if (unlikely(!(notbitstream & (0x1f0 << j)))) {
+				bitstream &= ~(0x100 << j);
+ 				bitbuf = (bitbuf & (((2 << j) << numbit) - 1)) |
+					((bitbuf & ~(((2 << j) << numbit) - 1)) << 1);
+				numbit++;
+				notbitstream = ~bitstream;
+			}
+		numbit += 8;
+		while (numbit >= 8) {
+			*wp++ = bitbuf;
+			bitbuf >>= 8;
+			numbit -= 8;
+		}
+	}
+	bitbuf |= 0x7e7e << numbit;
+	numbit += 16;
+	while (numbit >= 8) {
+		*wp++ = bitbuf;
+		bitbuf >>= 8;
+		numbit -= 8;
+	}
+	bc->hdlctx.bufptr = bc->hdlctx.buf;
+	bc->hdlctx.bufcnt = wp - bc->hdlctx.buf;
+	dev_kfree_skb(skb);
+	bc->dev->stats.tx_packets++;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int transmit(struct baycom_state *bc, int cnt, unsigned char stat)
+{
+	struct parport *pp = bc->pdev->port;
+	unsigned char tmp[128];
+	int i, j;
+
+	if (bc->hdlctx.state == tx_tail && !(stat & EPP_PTTBIT))
+		bc->hdlctx.state = tx_idle;
+	if (bc->hdlctx.state == tx_idle && bc->hdlctx.calibrate <= 0) {
+		if (bc->hdlctx.bufcnt <= 0)
+			encode_hdlc(bc);
+		if (bc->hdlctx.bufcnt <= 0)
+			return 0;
+		if (!bc->ch_params.fulldup) {
+			if (!(stat & EPP_DCDBIT)) {
+				bc->hdlctx.slotcnt = bc->ch_params.slottime;
+				return 0;
+			}
+			if ((--bc->hdlctx.slotcnt) > 0)
+				return 0;
+			bc->hdlctx.slotcnt = bc->ch_params.slottime;
+			if ((prandom_u32() % 256) > bc->ch_params.ppersist)
+				return 0;
+		}
+	}
+	if (bc->hdlctx.state == tx_idle && bc->hdlctx.bufcnt > 0) {
+		bc->hdlctx.state = tx_keyup;
+		bc->hdlctx.flags = tenms_to_flags(bc, bc->ch_params.tx_delay);
+		bc->ptt_keyed++;
+	}
+	while (cnt > 0) {
+		switch (bc->hdlctx.state) {
+		case tx_keyup:
+			i = min_t(int, cnt, bc->hdlctx.flags);
+			cnt -= i;
+			bc->hdlctx.flags -= i;
+			if (bc->hdlctx.flags <= 0)
+				bc->hdlctx.state = tx_data;
+			memset(tmp, 0x7e, sizeof(tmp));
+			while (i > 0) {
+				j = (i > sizeof(tmp)) ? sizeof(tmp) : i;
+				if (j != pp->ops->epp_write_data(pp, tmp, j, 0))
+					return -1;
+				i -= j;
+			}
+			break;
+
+		case tx_data:
+			if (bc->hdlctx.bufcnt <= 0) {
+				encode_hdlc(bc);
+				if (bc->hdlctx.bufcnt <= 0) {
+					bc->hdlctx.state = tx_tail;
+					bc->hdlctx.flags = tenms_to_flags(bc, bc->ch_params.tx_tail);
+					break;
+				}
+			}
+			i = min_t(int, cnt, bc->hdlctx.bufcnt);
+			bc->hdlctx.bufcnt -= i;
+			cnt -= i;
+			if (i != pp->ops->epp_write_data(pp, bc->hdlctx.bufptr, i, 0))
+					return -1;
+			bc->hdlctx.bufptr += i;
+			break;
+			
+		case tx_tail:
+			encode_hdlc(bc);
+			if (bc->hdlctx.bufcnt > 0) {
+				bc->hdlctx.state = tx_data;
+				break;
+			}
+			i = min_t(int, cnt, bc->hdlctx.flags);
+			if (i) {
+				cnt -= i;
+				bc->hdlctx.flags -= i;
+				memset(tmp, 0x7e, sizeof(tmp));
+				while (i > 0) {
+					j = (i > sizeof(tmp)) ? sizeof(tmp) : i;
+					if (j != pp->ops->epp_write_data(pp, tmp, j, 0))
+						return -1;
+					i -= j;
+				}
+				break;
+			}
+
+		default:  /* fall through */
+			if (bc->hdlctx.calibrate <= 0)
+				return 0;
+			i = min_t(int, cnt, bc->hdlctx.calibrate);
+			cnt -= i;
+			bc->hdlctx.calibrate -= i;
+			memset(tmp, 0, sizeof(tmp));
+			while (i > 0) {
+				j = (i > sizeof(tmp)) ? sizeof(tmp) : i;
+				if (j != pp->ops->epp_write_data(pp, tmp, j, 0))
+					return -1;
+				i -= j;
+			}
+			break;
+		}
+	}
+	return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static void do_rxpacket(struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+	struct sk_buff *skb;
+	unsigned char *cp;
+	unsigned pktlen;
+
+	if (bc->hdlcrx.bufcnt < 4) 
+		return;
+	if (!check_crc_ccitt(bc->hdlcrx.buf, bc->hdlcrx.bufcnt)) 
+		return;
+	pktlen = bc->hdlcrx.bufcnt-2+1; /* KISS kludge */
+	if (!(skb = dev_alloc_skb(pktlen))) {
+		printk("%s: memory squeeze, dropping packet\n", dev->name);
+		dev->stats.rx_dropped++;
+		return;
+	}
+	cp = skb_put(skb, pktlen);
+	*cp++ = 0; /* KISS kludge */
+	memcpy(cp, bc->hdlcrx.buf, pktlen - 1);
+	skb->protocol = ax25_type_trans(skb, dev);
+	netif_rx(skb);
+	dev->stats.rx_packets++;
+}
+
+static int receive(struct net_device *dev, int cnt)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+	struct parport *pp = bc->pdev->port;
+        unsigned int bitbuf, notbitstream, bitstream, numbits, state;
+	unsigned char tmp[128];
+        unsigned char *cp;
+	int cnt2, ret = 0;
+	int j;
+        
+        numbits = bc->hdlcrx.numbits;
+	state = bc->hdlcrx.state;
+	bitstream = bc->hdlcrx.bitstream;
+	bitbuf = bc->hdlcrx.bitbuf;
+	while (cnt > 0) {
+		cnt2 = (cnt > sizeof(tmp)) ? sizeof(tmp) : cnt;
+		cnt -= cnt2;
+		if (cnt2 != pp->ops->epp_read_data(pp, tmp, cnt2, 0)) {
+			ret = -1;
+			break;
+		}
+		cp = tmp;
+		for (; cnt2 > 0; cnt2--, cp++) {
+			bitstream >>= 8;
+			bitstream |= (*cp) << 8;
+			bitbuf >>= 8;
+			bitbuf |= (*cp) << 8;
+			numbits += 8;
+			notbitstream = ~bitstream;
+			for (j = 0; j < 8; j++) {
+
+				/* flag or abort */
+			        if (unlikely(!(notbitstream & (0x0fc << j)))) {
+
+					/* abort received */
+					if (!(notbitstream & (0x1fc << j)))
+						state = 0;
+
+					/* flag received */
+					else if ((bitstream & (0x1fe << j)) == (0x0fc << j)) {
+						if (state)
+							do_rxpacket(dev);
+						bc->hdlcrx.bufcnt = 0;
+						bc->hdlcrx.bufptr = bc->hdlcrx.buf;
+						state = 1;
+						numbits = 7-j;
+					}
+				}
+
+				/* stuffed bit */
+				else if (unlikely((bitstream & (0x1f8 << j)) == (0xf8 << j))) {
+					numbits--;
+					bitbuf = (bitbuf & ((~0xff) << j)) | ((bitbuf & ~((~0xff) << j)) << 1);
+					}
+				}
+			while (state && numbits >= 8) {
+				if (bc->hdlcrx.bufcnt >= TXBUFFER_SIZE) {
+					state = 0;
+				} else {
+					*(bc->hdlcrx.bufptr)++ = bitbuf >> (16-numbits);
+					bc->hdlcrx.bufcnt++;
+					numbits -= 8;
+				}
+			}
+		}
+	}
+        bc->hdlcrx.numbits = numbits;
+	bc->hdlcrx.state = state;
+	bc->hdlcrx.bitstream = bitstream;
+	bc->hdlcrx.bitbuf = bitbuf;
+	return ret;
+}
+
+/* --------------------------------------------------------------------- */
+
+#ifdef __i386__
+#include <asm/msr.h>
+#define GETTICK(x)                                                \
+({                                                                \
+	if (cpu_has_tsc)                                          \
+		rdtscl(x);                                        \
+})
+#else /* __i386__ */
+#define GETTICK(x)
+#endif /* __i386__ */
+
+static void epp_bh(struct work_struct *work)
+{
+	struct net_device *dev;
+	struct baycom_state *bc;
+	struct parport *pp;
+	unsigned char stat;
+	unsigned char tmp[2];
+	unsigned int time1 = 0, time2 = 0, time3 = 0;
+	int cnt, cnt2;
+
+	bc = container_of(work, struct baycom_state, run_work.work);
+	dev = bc->dev;
+	if (!bc->work_running)
+		return;
+	baycom_int_freq(bc);
+	pp = bc->pdev->port;
+	/* update status */
+	if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
+		goto epptimeout;
+	bc->stat = stat;
+	bc->debug_vals.last_pllcorr = stat;
+	GETTICK(time1);
+	if (bc->modem == EPP_FPGAEXTSTATUS) {
+		/* get input count */
+		tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE|1;
+		if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
+			goto epptimeout;
+		if (pp->ops->epp_read_addr(pp, tmp, 2, 0) != 2)
+			goto epptimeout;
+		cnt = tmp[0] | (tmp[1] << 8);
+		cnt &= 0x7fff;
+		/* get output count */
+		tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE|2;
+		if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
+			goto epptimeout;
+		if (pp->ops->epp_read_addr(pp, tmp, 2, 0) != 2)
+			goto epptimeout;
+		cnt2 = tmp[0] | (tmp[1] << 8);
+		cnt2 = 16384 - (cnt2 & 0x7fff);
+		/* return to normal */
+		tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE;
+		if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
+			goto epptimeout;
+		if (transmit(bc, cnt2, stat))
+			goto epptimeout;
+		GETTICK(time2);
+		if (receive(dev, cnt))
+			goto epptimeout;
+		if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
+			goto epptimeout;
+		bc->stat = stat;
+	} else {
+		/* try to tx */
+		switch (stat & (EPP_NTAEF|EPP_NTHF)) {
+		case EPP_NTHF:
+			cnt = 2048 - 256;
+			break;
+		
+		case EPP_NTAEF:
+			cnt = 2048 - 1793;
+			break;
+		
+		case 0:
+			cnt = 0;
+			break;
+		
+		default:
+			cnt = 2048 - 1025;
+			break;
+		}
+		if (transmit(bc, cnt, stat))
+			goto epptimeout;
+		GETTICK(time2);
+		/* do receiver */
+		while ((stat & (EPP_NRAEF|EPP_NRHF)) != EPP_NRHF) {
+			switch (stat & (EPP_NRAEF|EPP_NRHF)) {
+			case EPP_NRAEF:
+				cnt = 1025;
+				break;
+
+			case 0:
+				cnt = 1793;
+				break;
+
+			default:
+				cnt = 256;
+				break;
+			}
+			if (receive(dev, cnt))
+				goto epptimeout;
+			if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
+				goto epptimeout;
+		}
+		cnt = 0;
+		if (bc->bitrate < 50000)
+			cnt = 256;
+		else if (bc->bitrate < 100000)
+			cnt = 128;
+		while (cnt > 0 && stat & EPP_NREF) {
+			if (receive(dev, 1))
+				goto epptimeout;
+			cnt--;
+			if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
+				goto epptimeout;
+		}
+	}
+	GETTICK(time3);
+#ifdef BAYCOM_DEBUG
+	bc->debug_vals.mod_cycles = time2 - time1;
+	bc->debug_vals.demod_cycles = time3 - time2;
+#endif /* BAYCOM_DEBUG */
+	schedule_delayed_work(&bc->run_work, 1);
+	if (!bc->skb)
+		netif_wake_queue(dev);
+	return;
+ epptimeout:
+	printk(KERN_ERR "%s: EPP timeout!\n", bc_drvname);
+}
+
+/* ---------------------------------------------------------------------- */
+/*
+ * ===================== network driver interface =========================
+ */
+
+static int baycom_send_packet(struct sk_buff *skb, struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+
+	if (skb->protocol == htons(ETH_P_IP))
+		return ax25_ip_xmit(skb);
+
+	if (skb->data[0] != 0) {
+		do_kiss_params(bc, skb->data, skb->len);
+		dev_kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+	if (bc->skb)
+		return NETDEV_TX_LOCKED;
+	/* strip KISS byte */
+	if (skb->len >= HDLCDRV_MAXFLEN+1 || skb->len < 3) {
+		dev_kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+	netif_stop_queue(dev);
+	bc->skb = skb;
+	return NETDEV_TX_OK;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int baycom_set_mac_address(struct net_device *dev, void *addr)
+{
+	struct sockaddr *sa = (struct sockaddr *)addr;
+
+	/* addr is an AX.25 shifted ASCII mac address */
+	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); 
+	return 0;                                         
+}
+
+/* --------------------------------------------------------------------- */
+
+static void epp_wakeup(void *handle)
+{
+        struct net_device *dev = (struct net_device *)handle;
+        struct baycom_state *bc = netdev_priv(dev);
+
+        printk(KERN_DEBUG "baycom_epp: %s: why am I being woken up?\n", dev->name);
+        if (!parport_claim(bc->pdev))
+                printk(KERN_DEBUG "baycom_epp: %s: I'm broken.\n", dev->name);
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Open/initialize 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 need to be set once at boot, so that
+ * there is non-reboot way to recover if something goes wrong.
+ */
+
+static int epp_open(struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+        struct parport *pp = parport_find_base(dev->base_addr);
+	unsigned int i, j;
+	unsigned char tmp[128];
+	unsigned char stat;
+	unsigned long tstart;
+	
+        if (!pp) {
+                printk(KERN_ERR "%s: parport at 0x%lx unknown\n", bc_drvname, dev->base_addr);
+                return -ENXIO;
+        }
+#if 0
+        if (pp->irq < 0) {
+                printk(KERN_ERR "%s: parport at 0x%lx has no irq\n", bc_drvname, pp->base);
+		parport_put_port(pp);
+                return -ENXIO;
+        }
+#endif
+	if ((~pp->modes) & (PARPORT_MODE_TRISTATE | PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT)) {
+                printk(KERN_ERR "%s: parport at 0x%lx cannot be used\n",
+		       bc_drvname, pp->base);
+		parport_put_port(pp);
+                return -EIO;
+	}
+	memset(&bc->modem, 0, sizeof(bc->modem));
+        bc->pdev = parport_register_device(pp, dev->name, NULL, epp_wakeup, 
+					   NULL, PARPORT_DEV_EXCL, dev);
+	parport_put_port(pp);
+        if (!bc->pdev) {
+                printk(KERN_ERR "%s: cannot register parport at 0x%lx\n", bc_drvname, pp->base);
+                return -ENXIO;
+        }
+        if (parport_claim(bc->pdev)) {
+                printk(KERN_ERR "%s: parport at 0x%lx busy\n", bc_drvname, pp->base);
+                parport_unregister_device(bc->pdev);
+                return -EBUSY;
+        }
+        dev->irq = /*pp->irq*/ 0;
+	INIT_DELAYED_WORK(&bc->run_work, epp_bh);
+	bc->work_running = 1;
+	bc->modem = EPP_CONVENTIONAL;
+	if (eppconfig(bc))
+		printk(KERN_INFO "%s: no FPGA detected, assuming conventional EPP modem\n", bc_drvname);
+	else
+		bc->modem = /*EPP_FPGA*/ EPP_FPGAEXTSTATUS;
+	parport_write_control(pp, LPTCTRL_PROGRAM); /* prepare EPP mode; we aren't using interrupts */
+	/* reset the modem */
+	tmp[0] = 0;
+	tmp[1] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE;
+	if (pp->ops->epp_write_addr(pp, tmp, 2, 0) != 2)
+		goto epptimeout;
+	/* autoprobe baud rate */
+	tstart = jiffies;
+	i = 0;
+	while (time_before(jiffies, tstart + HZ/3)) {
+		if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
+			goto epptimeout;
+		if ((stat & (EPP_NRAEF|EPP_NRHF)) == EPP_NRHF) {
+			schedule();
+			continue;
+		}
+		if (pp->ops->epp_read_data(pp, tmp, 128, 0) != 128)
+			goto epptimeout;
+		if (pp->ops->epp_read_data(pp, tmp, 128, 0) != 128)
+			goto epptimeout;
+		i += 256;
+	}
+	for (j = 0; j < 256; j++) {
+		if (pp->ops->epp_read_addr(pp, &stat, 1, 0) != 1)
+			goto epptimeout;
+		if (!(stat & EPP_NREF))
+			break;
+		if (pp->ops->epp_read_data(pp, tmp, 1, 0) != 1)
+			goto epptimeout;
+		i++;
+	}
+	tstart = jiffies - tstart;
+	bc->bitrate = i * (8 * HZ) / tstart;
+	j = 1;
+	i = bc->bitrate >> 3;
+	while (j < 7 && i > 150) {
+		j++;
+		i >>= 1;
+	}
+	printk(KERN_INFO "%s: autoprobed bitrate: %d  int divider: %d  int rate: %d\n", 
+	       bc_drvname, bc->bitrate, j, bc->bitrate >> (j+2));
+	tmp[0] = EPP_TX_FIFO_ENABLE|EPP_RX_FIFO_ENABLE|EPP_MODEM_ENABLE/*|j*/;
+	if (pp->ops->epp_write_addr(pp, tmp, 1, 0) != 1)
+		goto epptimeout;
+	/*
+	 * initialise hdlc variables
+	 */
+	bc->hdlcrx.state = 0;
+	bc->hdlcrx.numbits = 0;
+	bc->hdlctx.state = tx_idle;
+	bc->hdlctx.bufcnt = 0;
+	bc->hdlctx.slotcnt = bc->ch_params.slottime;
+	bc->hdlctx.calibrate = 0;
+	/* start the bottom half stuff */
+	schedule_delayed_work(&bc->run_work, 1);
+	netif_start_queue(dev);
+	return 0;
+
+ epptimeout:
+	printk(KERN_ERR "%s: epp timeout during bitrate probe\n", bc_drvname);
+	parport_write_control(pp, 0); /* reset the adapter */
+        parport_release(bc->pdev);
+        parport_unregister_device(bc->pdev);
+	return -EIO;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int epp_close(struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+	struct parport *pp = bc->pdev->port;
+	unsigned char tmp[1];
+
+	bc->work_running = 0;
+	cancel_delayed_work_sync(&bc->run_work);
+	bc->stat = EPP_DCDBIT;
+	tmp[0] = 0;
+	pp->ops->epp_write_addr(pp, tmp, 1, 0);
+	parport_write_control(pp, 0); /* reset the adapter */
+        parport_release(bc->pdev);
+        parport_unregister_device(bc->pdev);
+	if (bc->skb)
+		dev_kfree_skb(bc->skb);
+	bc->skb = NULL;
+	printk(KERN_INFO "%s: close epp at iobase 0x%lx irq %u\n",
+	       bc_drvname, dev->base_addr, dev->irq);
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int baycom_setmode(struct baycom_state *bc, const char *modestr)
+{
+	const char *cp;
+
+	if (strstr(modestr,"intclk"))
+		bc->cfg.intclk = 1;
+	if (strstr(modestr,"extclk"))
+		bc->cfg.intclk = 0;
+	if (strstr(modestr,"intmodem"))
+		bc->cfg.extmodem = 0;
+	if (strstr(modestr,"extmodem"))
+		bc->cfg.extmodem = 1;
+	if (strstr(modestr,"noloopback"))
+		bc->cfg.loopback = 0;
+	if (strstr(modestr,"loopback"))
+		bc->cfg.loopback = 1;
+	if ((cp = strstr(modestr,"fclk="))) {
+		bc->cfg.fclk = simple_strtoul(cp+5, NULL, 0);
+		if (bc->cfg.fclk < 1000000)
+			bc->cfg.fclk = 1000000;
+		if (bc->cfg.fclk > 25000000)
+			bc->cfg.fclk = 25000000;
+	}
+	if ((cp = strstr(modestr,"bps="))) {
+		bc->cfg.bps = simple_strtoul(cp+4, NULL, 0);
+		if (bc->cfg.bps < 1000)
+			bc->cfg.bps = 1000;
+		if (bc->cfg.bps > 1500000)
+			bc->cfg.bps = 1500000;
+	}
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+	struct hdlcdrv_ioctl hi;
+
+	if (cmd != SIOCDEVPRIVATE)
+		return -ENOIOCTLCMD;
+
+	if (copy_from_user(&hi, ifr->ifr_data, sizeof(hi)))
+		return -EFAULT;
+	switch (hi.cmd) {
+	default:
+		return -ENOIOCTLCMD;
+
+	case HDLCDRVCTL_GETCHANNELPAR:
+		hi.data.cp.tx_delay = bc->ch_params.tx_delay;
+		hi.data.cp.tx_tail = bc->ch_params.tx_tail;
+		hi.data.cp.slottime = bc->ch_params.slottime;
+		hi.data.cp.ppersist = bc->ch_params.ppersist;
+		hi.data.cp.fulldup = bc->ch_params.fulldup;
+		break;
+
+	case HDLCDRVCTL_SETCHANNELPAR:
+		if (!capable(CAP_NET_ADMIN))
+			return -EACCES;
+		bc->ch_params.tx_delay = hi.data.cp.tx_delay;
+		bc->ch_params.tx_tail = hi.data.cp.tx_tail;
+		bc->ch_params.slottime = hi.data.cp.slottime;
+		bc->ch_params.ppersist = hi.data.cp.ppersist;
+		bc->ch_params.fulldup = hi.data.cp.fulldup;
+		bc->hdlctx.slotcnt = 1;
+		return 0;
+		
+	case HDLCDRVCTL_GETMODEMPAR:
+		hi.data.mp.iobase = dev->base_addr;
+		hi.data.mp.irq = dev->irq;
+		hi.data.mp.dma = dev->dma;
+		hi.data.mp.dma2 = 0;
+		hi.data.mp.seriobase = 0;
+		hi.data.mp.pariobase = 0;
+		hi.data.mp.midiiobase = 0;
+		break;
+
+	case HDLCDRVCTL_SETMODEMPAR:
+		if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
+			return -EACCES;
+		dev->base_addr = hi.data.mp.iobase;
+		dev->irq = /*hi.data.mp.irq*/0;
+		dev->dma = /*hi.data.mp.dma*/0;
+		return 0;	
+		
+	case HDLCDRVCTL_GETSTAT:
+		hi.data.cs.ptt = !!(bc->stat & EPP_PTTBIT);
+		hi.data.cs.dcd = !(bc->stat & EPP_DCDBIT);
+		hi.data.cs.ptt_keyed = bc->ptt_keyed;
+		hi.data.cs.tx_packets = dev->stats.tx_packets;
+		hi.data.cs.tx_errors = dev->stats.tx_errors;
+		hi.data.cs.rx_packets = dev->stats.rx_packets;
+		hi.data.cs.rx_errors = dev->stats.rx_errors;
+		break;		
+
+	case HDLCDRVCTL_OLDGETSTAT:
+		hi.data.ocs.ptt = !!(bc->stat & EPP_PTTBIT);
+		hi.data.ocs.dcd = !(bc->stat & EPP_DCDBIT);
+		hi.data.ocs.ptt_keyed = bc->ptt_keyed;
+		break;		
+
+	case HDLCDRVCTL_CALIBRATE:
+		if (!capable(CAP_SYS_RAWIO))
+			return -EACCES;
+		bc->hdlctx.calibrate = hi.data.calibrate * bc->bitrate / 8;
+		return 0;
+
+	case HDLCDRVCTL_DRIVERNAME:
+		strncpy(hi.data.drivername, "baycom_epp", sizeof(hi.data.drivername));
+		break;
+		
+	case HDLCDRVCTL_GETMODE:
+		sprintf(hi.data.modename, "%sclk,%smodem,fclk=%d,bps=%d%s", 
+			bc->cfg.intclk ? "int" : "ext",
+			bc->cfg.extmodem ? "ext" : "int", bc->cfg.fclk, bc->cfg.bps,
+			bc->cfg.loopback ? ",loopback" : "");
+		break;
+
+	case HDLCDRVCTL_SETMODE:
+		if (!capable(CAP_NET_ADMIN) || netif_running(dev))
+			return -EACCES;
+		hi.data.modename[sizeof(hi.data.modename)-1] = '\0';
+		return baycom_setmode(bc, hi.data.modename);
+
+	case HDLCDRVCTL_MODELIST:
+		strncpy(hi.data.modename, "intclk,extclk,intmodem,extmodem,divider=x",
+			sizeof(hi.data.modename));
+		break;
+
+	case HDLCDRVCTL_MODEMPARMASK:
+		return HDLCDRV_PARMASK_IOBASE;
+
+	}
+	if (copy_to_user(ifr->ifr_data, &hi, sizeof(hi)))
+		return -EFAULT;
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static const struct net_device_ops baycom_netdev_ops = {
+	.ndo_open	     = epp_open,
+	.ndo_stop	     = epp_close,
+	.ndo_do_ioctl	     = baycom_ioctl,
+	.ndo_start_xmit      = baycom_send_packet,
+	.ndo_set_mac_address = baycom_set_mac_address,
+};
+
+/*
+ * Check for a network adaptor of this type, and return '0' if one exists.
+ * If dev->base_addr == 0, probe all likely locations.
+ * If dev->base_addr == 1, always return failure.
+ * If dev->base_addr == 2, allocate space for the device and return success
+ * (detachable devices only).
+ */
+static void baycom_probe(struct net_device *dev)
+{
+	const struct hdlcdrv_channel_params dflt_ch_params = { 
+		20, 2, 10, 40, 0 
+	};
+	struct baycom_state *bc;
+
+	/*
+	 * not a real probe! only initialize data structures
+	 */
+	bc = netdev_priv(dev);
+	/*
+	 * initialize the baycom_state struct
+	 */
+	bc->ch_params = dflt_ch_params;
+	bc->ptt_keyed = 0;
+
+	/*
+	 * initialize the device struct
+	 */
+
+	/* Fill in the fields of the device structure */
+	bc->skb = NULL;
+	
+	dev->netdev_ops = &baycom_netdev_ops;
+	dev->header_ops = &ax25_header_ops;
+	
+	dev->type = ARPHRD_AX25;           /* AF_AX25 device */
+	dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
+	dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
+	dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
+	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
+	memcpy(dev->dev_addr, &null_ax25_address, AX25_ADDR_LEN);
+	dev->tx_queue_len = 16;
+
+	/* New style flags */
+	dev->flags = 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * command line settable parameters
+ */
+static char *mode[NR_PORTS] = { "", };
+static int iobase[NR_PORTS] = { 0x378, };
+
+module_param_array(mode, charp, NULL, 0);
+MODULE_PARM_DESC(mode, "baycom operating mode");
+module_param_array(iobase, int, NULL, 0);
+MODULE_PARM_DESC(iobase, "baycom io base address");
+
+MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
+MODULE_DESCRIPTION("Baycom epp amateur radio modem driver");
+MODULE_LICENSE("GPL");
+
+/* --------------------------------------------------------------------- */
+
+static void __init baycom_epp_dev_setup(struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+
+	/*
+	 * initialize part of the baycom_state struct
+	 */
+	bc->dev = dev;
+	bc->magic = BAYCOM_MAGIC;
+	bc->cfg.fclk = 19666600;
+	bc->cfg.bps = 9600;
+	/*
+	 * initialize part of the device struct
+	 */
+	baycom_probe(dev);
+}
+
+static int __init init_baycomepp(void)
+{
+	int i, found = 0;
+	char set_hw = 1;
+
+	printk(bc_drvinfo);
+	/*
+	 * register net devices
+	 */
+	for (i = 0; i < NR_PORTS; i++) {
+		struct net_device *dev;
+		
+		dev = alloc_netdev(sizeof(struct baycom_state), "bce%d",
+				   NET_NAME_UNKNOWN, baycom_epp_dev_setup);
+
+		if (!dev) {
+			printk(KERN_WARNING "bce%d : out of memory\n", i);
+			return found ? 0 : -ENOMEM;
+		}
+			
+		sprintf(dev->name, "bce%d", i);
+		dev->base_addr = iobase[i];
+
+		if (!mode[i])
+			set_hw = 0;
+		if (!set_hw)
+			iobase[i] = 0;
+
+		if (register_netdev(dev)) {
+			printk(KERN_WARNING "%s: cannot register net device %s\n", bc_drvname, dev->name);
+			free_netdev(dev);
+			break;
+		}
+		if (set_hw && baycom_setmode(netdev_priv(dev), mode[i]))
+			set_hw = 0;
+		baycom_device[i] = dev;
+		found++;
+	}
+
+	return found ? 0 : -ENXIO;
+}
+
+static void __exit cleanup_baycomepp(void)
+{
+	int i;
+
+	for(i = 0; i < NR_PORTS; i++) {
+		struct net_device *dev = baycom_device[i];
+
+		if (dev) {
+			struct baycom_state *bc = netdev_priv(dev);
+			if (bc->magic == BAYCOM_MAGIC) {
+				unregister_netdev(dev);
+				free_netdev(dev);
+			} else
+				printk(paranoia_str, "cleanup_module");
+		}
+	}
+}
+
+module_init(init_baycomepp);
+module_exit(cleanup_baycomepp);
+
+/* --------------------------------------------------------------------- */
+
+#ifndef MODULE
+
+/*
+ * format: baycom_epp=io,mode
+ * mode: fpga config options
+ */
+
+static int __init baycom_epp_setup(char *str)
+{
+        static unsigned __initdata nr_dev = 0;
+	int ints[2];
+
+        if (nr_dev >= NR_PORTS)
+                return 0;
+	str = get_options(str, 2, ints);
+	if (ints[0] < 1)
+		return 0;
+	mode[nr_dev] = str;
+	iobase[nr_dev] = ints[1];
+	nr_dev++;
+	return 1;
+}
+
+__setup("baycom_epp=", baycom_epp_setup);
+
+#endif /* MODULE */
+/* --------------------------------------------------------------------- */