/*****************************************************************************/
/*
* baycom_ser_fdx.c -- baycom ser12 fullduplex radio modem driver.
*
* Copyright (C) 1996-2000 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.
*
*
* Supported modems
*
* ser12: This is a very simple 1200 baud AFSK modem. The modem consists only
* of a modulator/demodulator chip, usually a TI TCM3105. The computer
* is responsible for regenerating the receiver bit clock, as well as
* for handling the HDLC protocol. The modem connects to a serial port,
* hence the name. Since the serial port is not used as an async serial
* port, the kernel driver for serial ports cannot be used, and this
* driver only supports standard serial hardware (8250, 16450, 16550A)
*
* This modem usually draws its supply current out of the otherwise unused
* TXD pin of the serial port. Thus a contiguous stream of 0x00-bytes
* is transmitted to achieve a positive supply voltage.
*
* hsk: This is a 4800 baud FSK modem, designed for TNC use. It works fine
* in 'baycom-mode' :-) In contrast to the TCM3105 modem, power is
* externally supplied. So there's no need to provide the 0x00-byte-stream
* when receiving or idle, which drastically reduces interrupt load.
*
* Command line options (insmod command line)
*
* mode ser# hardware DCD
* ser#* software DCD
* ser#+ hardware DCD, inverted signal at DCD pin
* '#' denotes the baud rate / 100, eg. ser12* is '1200 baud, soft DCD'
* iobase base address of the port; common values are 0x3f8, 0x2f8, 0x3e8, 0x2e8
* baud baud rate (between 300 and 4800)
* irq interrupt line of the port; common values are 4,3
*
*
* History:
* 0.1 26.06.1996 Adapted from baycom.c and made network driver interface
* 18.10.1996 Changed to new user space access routines (copy_{to,from}_user)
* 0.3 26.04.1997 init code/data tagged
* 0.4 08.07.1997 alternative ser12 decoding algorithm (uses delta CTS ints)
* 0.5 11.11.1997 ser12/par96 split into separate files
* 0.6 24.01.1998 Thorsten Kranzkowski, dl8bcu and Thomas Sailer:
* reduced interrupt load in transmit case
* reworked receiver
* 0.7 03.08.1999 adapt to Linus' new __setup/__initcall
* 0.8 10.08.1999 use module_init/module_exit
* 0.9 12.02.2000 adapted to softnet driver interface
* 0.10 03.07.2000 fix interface name handling
*/
/*****************************************************************************/
#include <linux/capability.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/hdlcdrv.h>
#include <linux/baycom.h>
#include <linux/jiffies.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
/* --------------------------------------------------------------------- */
#define BAYCOM_DEBUG
/* --------------------------------------------------------------------- */
static const char bc_drvname[] = "baycom_ser_fdx";
static const char bc_drvinfo[] = KERN_INFO "baycom_ser_fdx: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n"
"baycom_ser_fdx: version 0.10\n";
/* --------------------------------------------------------------------- */
#define NR_PORTS 4
static struct net_device *baycom_device[NR_PORTS];
/* --------------------------------------------------------------------- */
#define RBR(iobase) (iobase+0)
#define THR(iobase) (iobase+0)
#define IER(iobase) (iobase+1)
#define IIR(iobase) (iobase+2)
#define FCR(iobase) (iobase+2)
#define LCR(iobase) (iobase+3)
#define MCR(iobase) (iobase+4)
#define LSR(iobase) (iobase+5)
#define MSR(iobase) (iobase+6)
#define SCR(iobase) (iobase+7)
#define DLL(iobase) (iobase+0)
#define DLM(iobase) (iobase+1)
#define SER12_EXTENT 8
/* ---------------------------------------------------------------------- */
/*
* Information that need to be kept for each board.
*/
struct baycom_state {
struct hdlcdrv_state hdrv;
unsigned int baud, baud_us, baud_arbdiv, baud_uartdiv, baud_dcdtimeout;
int opt_dcd;
struct modem_state {
unsigned char flags;
unsigned char ptt;
unsigned int shreg;
struct modem_state_ser12 {
unsigned char tx_bit;
unsigned char last_rxbit;
int dcd_sum0, dcd_sum1, dcd_sum2;
int dcd_time;
unsigned int pll_time;
unsigned int txshreg;
} ser12;
} modem;
#ifdef BAYCOM_DEBUG
struct debug_vals {
unsigned long last_jiffies;
unsigned cur_intcnt;
unsigned last_intcnt;
int cur_pllcorr;
int last_pllcorr;
} debug_vals;
#endif /* BAYCOM_DEBUG */
};
/* --------------------------------------------------------------------- */
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 */
}
/* --------------------------------------------------------------------- */
/*
* ===================== SER12 specific routines =========================
*/
/* --------------------------------------------------------------------- */
static inline void ser12_set_divisor(struct net_device *dev,
unsigned int divisor)
{
outb(0x81, LCR(dev->base_addr)); /* DLAB = 1 */
outb(divisor, DLL(dev->base_addr));
outb(divisor >> 8, DLM(dev->base_addr));
outb(0x01, LCR(dev->base_addr)); /* word length = 6 */
/*
* make sure the next interrupt is generated;
* 0 must be used to power the modem; the modem draws its
* power from the TxD line
*/
outb(0x00, THR(dev->base_addr));
/*
* it is important not to set the divider while transmitting;
* this reportedly makes some UARTs generating interrupts
* in the hundredthousands per second region
* Reported by: Ignacio.Arenaza@studi.epfl.ch (Ignacio Arenaza Nuno)
*/
}
/* --------------------------------------------------------------------- */
#if 0
static inline unsigned int hweight16(unsigned int w)
__attribute__ ((unused));
static inline unsigned int hweight8(unsigned int w)
__attribute__ ((unused));
static inline unsigned int hweight16(unsigned int w)
{
unsigned short res = (w & 0x5555) + ((w >> 1) & 0x5555);
res = (res & 0x3333) + ((res >> 2) & 0x3333);
res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
return (res & 0x00FF) + ((res >> 8) & 0x00FF);
}
static inline unsigned int hweight8(unsigned int w)
{
unsigned short res = (w & 0x55) + ((w >> 1) & 0x55);
res = (res & 0x33) + ((res >> 2) & 0x33);
return (res & 0x0F) + ((res >> 4) & 0x0F);
}
#endif
/* --------------------------------------------------------------------- */
static __inline__ void ser12_rx(struct net_device *dev, struct baycom_state *bc, struct timeval *tv, unsigned char curs)
{
int timediff;
int bdus8 = bc->baud_us >> 3;
int bdus4 = bc->baud_us >> 2;
int bdus2 = bc->baud_us >> 1;
timediff = 1000000 + tv->tv_usec - bc->modem.ser12.pll_time;
while (timediff >= 500000)
timediff -= 1000000;
while (timediff >= bdus2) {
timediff -= bc->baud_us;
bc->modem.ser12.pll_time += bc->baud_us;
bc->modem.ser12.dcd_time--;
/* first check if there is room to add a bit */
if (bc->modem.shreg & 1) {
hdlcdrv_putbits(&bc->hdrv, (bc->modem.shreg >> 1) ^ 0xffff);
bc->modem.shreg = 0x10000;
}
/* add a one bit */
bc->modem.shreg >>= 1;
}
if (bc->modem.ser12.dcd_time <= 0) {
if (!bc->opt_dcd)
hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
bc->modem.ser12.dcd_sum1 +
bc->modem.ser12.dcd_sum2) < 0);
bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
bc->modem.ser12.dcd_sum0 = 2; /* slight bias */
bc->modem.ser12.dcd_time += 120;
}
if (bc->modem.ser12.last_rxbit != curs) {
bc->modem.ser12.last_rxbit = curs;
bc->modem.shreg |= 0x10000;
/* adjust the PLL */
if (timediff > 0)
bc->modem.ser12.pll_time += bdus8;
else
bc->modem.ser12.pll_time += 1000000 - bdus8;
/* update DCD */
if (abs(timediff) > bdus4)
bc->modem.ser12.dcd_sum0 += 4;
else
bc->modem.ser12.dcd_sum0--;
#ifdef BAYCOM_DEBUG
bc->debug_vals.cur_pllcorr = timediff;
#endif /* BAYCOM_DEBUG */
}
while (bc->modem.ser12.pll_time >= 1000000)
bc->modem.ser12.pll_time -= 1000000;
}
/* --------------------------------------------------------------------- */
static irqreturn_t ser12_interrupt(int irq, void *dev_id)
{
struct net_device *dev = (struct net_device *)dev_id;
struct baycom_state *bc = netdev_priv(dev);
struct timeval tv;
unsigned char iir, msr;
unsigned int txcount = 0;
if (!bc || bc->hdrv.magic != HDLCDRV_MAGIC)
return IRQ_NONE;
/* fast way out for shared irq */
if ((iir = inb(IIR(dev->base_addr))) & 1)
return IRQ_NONE;
/* get current time */
do_gettimeofday(&tv);
msr = inb(MSR(dev->base_addr));
/* delta DCD */
if ((msr & 8) && bc->opt_dcd)
hdlcdrv_setdcd(&bc->hdrv, !((msr ^ bc->opt_dcd) & 0x80));
do {
switch (iir & 6) {
case 6:
inb(LSR(dev->base_addr));
break;
case 4:
inb(RBR(dev->base_addr));
break;
case 2:
/*
* make sure the next interrupt is generated;
* 0 must be used to power the modem; the modem draws its
* power from the TxD line
*/
outb(0x00, THR(dev->base_addr));
baycom_int_freq(bc);
txcount++;
/*
* first output the last bit (!) then call HDLC transmitter,
* since this may take quite long
*/
if (bc->modem.ptt)
outb(0x0e | (!!bc->modem.ser12.tx_bit), MCR(dev->base_addr));
else
outb(0x0d, MCR(dev->base_addr)); /* transmitter off */
break;
default:
msr = inb(MSR(dev->base_addr));
/* delta DCD */
if ((msr & 8) && bc->opt_dcd)
hdlcdrv_setdcd(&bc->hdrv, !((msr ^ bc->opt_dcd) & 0x80));
break;
}
iir = inb(IIR(dev->base_addr));
} while (!(iir & 1));
ser12_rx(dev, bc, &tv, msr & 0x10); /* CTS */
if (bc->modem.ptt && txcount) {
if (bc->modem.ser12.txshreg <= 1) {
bc->modem.ser12.txshreg = 0x10000 | hdlcdrv_getbits(&bc->hdrv);
if (!hdlcdrv_ptt(&bc->hdrv)) {
ser12_set_divisor(dev, 115200/100/8);
bc->modem.ptt = 0;
goto end_transmit;
}
}
bc->modem.ser12.tx_bit = !(bc->modem.ser12.tx_bit ^ (bc->modem.ser12.txshreg & 1));
bc->modem.ser12.txshreg >>= 1;
}
end_transmit:
local_irq_enable();
if (!bc->modem.ptt && txcount) {
hdlcdrv_arbitrate(dev, &bc->hdrv);
if (hdlcdrv_ptt(&bc->hdrv)) {
ser12_set_divisor(dev, bc->baud_uartdiv);
bc->modem.ser12.txshreg = 1;
bc->modem.ptt = 1;
}
}
hdlcdrv_transmitter(dev, &bc->hdrv);
hdlcdrv_receiver(dev, &bc->hdrv);
local_irq_disable();
return IRQ_HANDLED;
}
/* --------------------------------------------------------------------- */
enum uart { c_uart_unknown, c_uart_8250,
c_uart_16450, c_uart_16550, c_uart_16550A};
static const char *uart_str[] = {
"unknown", "8250", "16450", "16550", "16550A"
};
static enum uart ser12_check_uart(unsigned int iobase)
{
unsigned char b1,b2,b3;
enum uart u;
enum uart uart_tab[] =
{ c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A };
b1 = inb(MCR(iobase));
outb(b1 | 0x10, MCR(iobase)); /* loopback mode */
b2 = inb(MSR(iobase));
outb(0x1a, MCR(iobase));
b3 = inb(MSR(iobase)) & 0xf0;
outb(b1, MCR(iobase)); /* restore old values */
outb(b2, MSR(iobase));
if (b3 != 0x90)
return c_uart_unknown;
inb(RBR(iobase));
inb(RBR(iobase));
outb(0x01, FCR(iobase)); /* enable FIFOs */
u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
if (u == c_uart_16450) {
outb(0x5a, SCR(iobase));
b1 = inb(SCR(iobase));
outb(0xa5, SCR(iobase));
b2 = inb(SCR(iobase));
if ((b1 != 0x5a) || (b2 != 0xa5))
u = c_uart_8250;
}
return u;
}
/* --------------------------------------------------------------------- */
static int ser12_open(struct net_device *dev)
{
struct baycom_state *bc = netdev_priv(dev);
enum uart u;
if (!dev || !bc)
return -ENXIO;
if (!dev->base_addr || dev->base_addr > 0xffff-SER12_EXTENT ||
dev->irq < 2 || dev->irq > nr_irqs) {
printk(KERN_INFO "baycom_ser_fdx: invalid portnumber (max %u) "
"or irq (2 <= irq <= %d)\n",
0xffff-SER12_EXTENT, nr_irqs);
return -ENXIO;
}
if (bc->baud < 300 || bc->baud > 4800) {
printk(KERN_INFO "baycom_ser_fdx: invalid baudrate "
"(300...4800)\n");
return -EINVAL;
}
if (!request_region(dev->base_addr, SER12_EXTENT, "baycom_ser_fdx")) {
printk(KERN_WARNING "BAYCOM_SER_FSX: I/O port 0x%04lx busy\n",
dev->base_addr);
return -EACCES;
}
memset(&bc->modem, 0, sizeof(bc->modem));
bc->hdrv.par.bitrate = bc->baud;
bc->baud_us = 1000000/bc->baud;
bc->baud_uartdiv = (115200/8)/bc->baud;
if ((u = ser12_check_uart(dev->base_addr)) == c_uart_unknown){
release_region(dev->base_addr, SER12_EXTENT);
return -EIO;
}
outb(0, FCR(dev->base_addr)); /* disable FIFOs */
outb(0x0d, MCR(dev->base_addr));
outb(0, IER(dev->base_addr));
if (request_irq(dev->irq, ser12_interrupt, IRQF_DISABLED | IRQF_SHARED,
"baycom_ser_fdx", dev)) {
release_region(dev->base_addr, SER12_EXTENT);
return -EBUSY;
}
/*
* set the SIO to 6 Bits/character; during receive,
* the baud rate is set to produce 100 ints/sec
* to feed the channel arbitration process,
* during transmit to baud ints/sec to run
* the transmitter
*/
ser12_set_divisor(dev, 115200/100/8);
/*
* enable transmitter empty interrupt and modem status interrupt
*/
outb(0x0a, IER(dev->base_addr));
/*
* make sure the next interrupt is generated;
* 0 must be used to power the modem; the modem draws its
* power from the TxD line
*/
outb(0x00, THR(dev->base_addr));
hdlcdrv_setdcd(&bc->hdrv, 0);
printk(KERN_INFO "%s: ser_fdx at iobase 0x%lx irq %u baud %u uart %s\n",
bc_drvname, dev->base_addr, dev->irq, bc->baud, uart_str[u]);
return 0;
}
/* --------------------------------------------------------------------- */
static int ser12_close(struct net_device *dev)
{
struct baycom_state *bc = netdev_priv(dev);
if (!dev || !bc)
return -EINVAL;
/*
* disable interrupts
*/
outb(0, IER(dev->base_addr));
outb(1, MCR(dev->base_addr));
free_irq(dev->irq, dev);
release_region(dev->base_addr, SER12_EXTENT);
printk(KERN_INFO "%s: close ser_fdx at iobase 0x%lx irq %u\n",
bc_drvname, dev->base_addr, dev->irq);
return 0;
}
/* --------------------------------------------------------------------- */
/*
* ===================== hdlcdrv driver interface =========================
*/
/* --------------------------------------------------------------------- */
static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
struct hdlcdrv_ioctl *hi, int cmd);
/* --------------------------------------------------------------------- */
static struct hdlcdrv_ops ser12_ops = {
.drvname = bc_drvname,
.drvinfo = bc_drvinfo,
.open = ser12_open,
.close = ser12_close,
.ioctl = baycom_ioctl,
};
/* --------------------------------------------------------------------- */
static int baycom_setmode(struct baycom_state *bc, const char *modestr)
{
unsigned int baud;
if (!strncmp(modestr, "ser", 3)) {
baud = simple_strtoul(modestr+3, NULL, 10);
if (baud >= 3 && baud <= 48)
bc->baud = baud*100;
}
if (strchr(modestr, '*'))
bc->opt_dcd = 0;
else if (strchr(modestr, '+'))
bc->opt_dcd = -1;
else
bc->opt_dcd = 1;
return 0;
}
/* --------------------------------------------------------------------- */
static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
struct hdlcdrv_ioctl *hi, int cmd)
{
struct baycom_state *bc;
struct baycom_ioctl bi;
if (!dev)
return -EINVAL;
bc = netdev_priv(dev);
BUG_ON(bc->hdrv.magic != HDLCDRV_MAGIC);
if (cmd != SIOCDEVPRIVATE)
return -ENOIOCTLCMD;
switch (hi->cmd) {
default:
break;
case HDLCDRVCTL_GETMODE:
sprintf(hi->data.modename, "ser%u", bc->baud / 100);
if (bc->opt_dcd <= 0)
strcat(hi->data.modename, (!bc->opt_dcd) ? "*" : "+");
if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
return -EFAULT;
return 0;
case HDLCDRVCTL_SETMODE:
if (netif_running(dev) || !capable(CAP_NET_ADMIN))
return -EACCES;
hi->data.modename[sizeof(hi->data.modename)-1] = '\0';
return baycom_setmode(bc, hi->data.modename);
case HDLCDRVCTL_MODELIST:
strcpy(hi->data.modename, "ser12,ser3,ser24");
if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
return -EFAULT;
return 0;
case HDLCDRVCTL_MODEMPARMASK:
return HDLCDRV_PARMASK_IOBASE | HDLCDRV_PARMASK_IRQ;
}
if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
return -EFAULT;
switch (bi.cmd) {
default:
return -ENOIOCTLCMD;
#ifdef BAYCOM_DEBUG
case BAYCOMCTL_GETDEBUG:
bi.data.dbg.debug1 = bc->hdrv.ptt_keyed;
bi.data.dbg.debug2 = bc->debug_vals.last_intcnt;
bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr;
break;
#endif /* BAYCOM_DEBUG */
}
if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
return -EFAULT;
return 0;
}
/* --------------------------------------------------------------------- */
/*
* command line settable parameters
*/
static char *mode[NR_PORTS] = { "ser12*", };
static int iobase[NR_PORTS] = { 0x3f8, };
static int irq[NR_PORTS] = { 4, };
static int baud[NR_PORTS] = { [0 ... NR_PORTS-1] = 1200 };
module_param_array(mode, charp, NULL, 0);
MODULE_PARM_DESC(mode, "baycom operating mode; * for software DCD");
module_param_array(iobase, int, NULL, 0);
MODULE_PARM_DESC(iobase, "baycom io base address");
module_param_array(irq, int, NULL, 0);
MODULE_PARM_DESC(irq, "baycom irq number");
module_param_array(baud, int, NULL, 0);
MODULE_PARM_DESC(baud, "baycom baud rate (300 to 4800)");
MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
MODULE_DESCRIPTION("Baycom ser12 full duplex amateur radio modem driver");
MODULE_LICENSE("GPL");
/* --------------------------------------------------------------------- */
static int __init init_baycomserfdx(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;
struct baycom_state *bc;
char ifname[IFNAMSIZ];
sprintf(ifname, "bcsf%d", i);
if (!mode[i])
set_hw = 0;
if (!set_hw)
iobase[i] = irq[i] = 0;
dev = hdlcdrv_register(&ser12_ops,
sizeof(struct baycom_state),
ifname, iobase[i], irq[i], 0);
if (IS_ERR(dev))
break;
bc = netdev_priv(dev);
if (set_hw && baycom_setmode(bc, mode[i]))
set_hw = 0;
bc->baud = baud[i];
found++;
baycom_device[i] = dev;
}
if (!found)
return -ENXIO;
return 0;
}
static void __exit cleanup_baycomserfdx(void)
{
int i;
for(i = 0; i < NR_PORTS; i++) {
struct net_device *dev = baycom_device[i];
if (dev)
hdlcdrv_unregister(dev);
}
}
module_init(init_baycomserfdx);
module_exit(cleanup_baycomserfdx);
/* --------------------------------------------------------------------- */
#ifndef MODULE
/*
* format: baycom_ser_fdx=io,irq,mode
* mode: ser# hardware DCD
* ser#* software DCD
* ser#+ hardware DCD, inverted signal at DCD pin
* '#' denotes the baud rate / 100, eg. ser12* is '1200 baud, soft DCD'
*/
static int __init baycom_ser_fdx_setup(char *str)
{
static unsigned nr_dev;
int ints[4];
if (nr_dev >= NR_PORTS)
return 0;
str = get_options(str, 4, ints);
if (ints[0] < 2)
return 0;
mode[nr_dev] = str;
iobase[nr_dev] = ints[1];
irq[nr_dev] = ints[2];
if (ints[0] >= 3)
baud[nr_dev] = ints[3];
nr_dev++;
return 1;
}
__setup("baycom_ser_fdx=", baycom_ser_fdx_setup);
#endif /* MODULE */
/* --------------------------------------------------------------------- */