// SPDX-License-Identifier: GPL-2.0-or-later
/*****************************************************************************/
/*
* baycom_epp.c -- baycom epp radio modem driver.
*
* Copyright (C) 1998-2000
* Thomas Sailer (sailer@ife.ee.ethz.ch)
*
* 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 <linux/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 const eppconfig_path[] = "/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[] = {
(char *)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 (get_random_u8() > 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;
}
fallthrough;
default:
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;
}
/* --------------------------------------------------------------------- */
#define GETTICK(x) \
({ \
x = (unsigned int)get_cycles(); \
})
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 netdev_tx_t 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) {
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
/* 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 */
dev_addr_set(dev, sa->sa_data);
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;
struct pardev_cb par_cb;
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));
memset(&par_cb, 0, sizeof(par_cb));
par_cb.wakeup = epp_wakeup;
par_cb.private = (void *)dev;
par_cb.flags = PARPORT_DEV_EXCL;
for (i = 0; i < NR_PORTS; i++)
if (baycom_device[i] == dev)
break;
if (i == NR_PORTS) {
pr_err("%s: no device found\n", bc_drvname);
parport_put_port(pp);
return -ENODEV;
}
bc->pdev = parport_register_dev_model(pp, dev->name, &par_cb, i);
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);
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,"loopback"))
bc->cfg.loopback = 1;
if (strstr(modestr, "noloopback"))
bc->cfg.loopback = 0;
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_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
void __user *data, int cmd)
{
struct baycom_state *bc = netdev_priv(dev);
struct hdlcdrv_ioctl hi;
if (cmd != SIOCDEVPRIVATE)
return -ENOIOCTLCMD;
if (copy_from_user(&hi, 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(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_siocdevprivate = baycom_siocdevprivate,
.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);
dev_addr_set(dev, (u8 *)&null_ax25_address);
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_hw_array(iobase, int, ioport, 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 int baycom_epp_par_probe(struct pardevice *par_dev)
{
struct device_driver *drv = par_dev->dev.driver;
int len = strlen(drv->name);
if (strncmp(par_dev->name, drv->name, len))
return -ENODEV;
return 0;
}
static struct parport_driver baycom_epp_par_driver = {
.name = "bce",
.probe = baycom_epp_par_probe,
.devmodel = true,
};
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, ret;
char set_hw = 1;
printk(bc_drvinfo);
ret = parport_register_driver(&baycom_epp_par_driver);
if (ret)
return ret;
/*
* 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++;
}
if (found == 0) {
parport_unregister_driver(&baycom_epp_par_driver);
return -ENXIO;
}
return 0;
}
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");
}
}
parport_unregister_driver(&baycom_epp_par_driver);
}
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 */
/* --------------------------------------------------------------------- */