diff options
Diffstat (limited to 'drivers/net/hamradio/baycom_par.c')
-rw-r--r-- | drivers/net/hamradio/baycom_par.c | 599 |
1 files changed, 599 insertions, 0 deletions
diff --git a/drivers/net/hamradio/baycom_par.c b/drivers/net/hamradio/baycom_par.c new file mode 100644 index 000000000..fd7da5bb1 --- /dev/null +++ b/drivers/net/hamradio/baycom_par.c @@ -0,0 +1,599 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/*****************************************************************************/ + +/* + * baycom_par.c -- baycom par96 and picpar radio modem driver. + * + * Copyright (C) 1996-2000 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. + * + * Supported modems + * + * par96: This is a modem for 9600 baud FSK compatible to the G3RUH standard. + * The modem does all the filtering and regenerates the receiver clock. + * Data is transferred from and to the PC via a shift register. + * The shift register is filled with 16 bits and an interrupt is + * signalled. The PC then empties the shift register in a burst. This + * modem connects to the parallel port, hence the name. The modem + * leaves the implementation of the HDLC protocol and the scrambler + * polynomial to the PC. This modem is no longer available (at least + * from Baycom) and has been replaced by the PICPAR modem (see below). + * You may however still build one from the schematics published in + * cq-DL :-). + * + * picpar: This is a redesign of the par96 modem by Henning Rech, DF9IC. The + * modem is protocol compatible to par96, but uses only three low + * power ICs and can therefore be fed from the parallel port and + * does not require an additional power supply. It features + * built in DCD circuitry. The driver should therefore be configured + * for hardware DCD. + * + * Command line options (insmod command line) + * + * mode driver mode string. Valid choices are par96 and picpar. + * iobase base address of the port; common values are 0x378, 0x278, 0x3bc + * + * 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 split into separate files for ser12/par96 + * 0.6 03.08.1999 adapt to Linus' new __setup/__initcall + * removed some pre-2.2 kernel compatibility cruft + * 0.7 10.08.1999 Check if parport can do SPP and is safe to access during interrupt contexts + * 0.8 12.02.2000 adapted to softnet driver interface + * removed direct parport access, uses parport driver methods + * 0.9 03.07.2000 fix interface name handling + */ + +/*****************************************************************************/ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/fcntl.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/in.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/netdevice.h> +#include <linux/hdlcdrv.h> +#include <linux/baycom.h> +#include <linux/parport.h> +#include <linux/bitops.h> +#include <linux/jiffies.h> + +#include <linux/uaccess.h> + +/* --------------------------------------------------------------------- */ + +#define BAYCOM_DEBUG + +/* + * modem options; bit mask + */ +#define BAYCOM_OPTIONS_SOFTDCD 1 + +/* --------------------------------------------------------------------- */ + +static const char bc_drvname[] = "baycom_par"; +static const char bc_drvinfo[] = KERN_INFO "baycom_par: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n" +"baycom_par: version 0.9\n"; + +/* --------------------------------------------------------------------- */ + +#define NR_PORTS 4 + +static struct net_device *baycom_device[NR_PORTS]; + +/* --------------------------------------------------------------------- */ + +#define PAR96_BURSTBITS 16 +#define PAR96_BURST 4 +#define PAR96_PTT 2 +#define PAR96_TXBIT 1 +#define PAR96_ACK 0x40 +#define PAR96_RXBIT 0x20 +#define PAR96_DCD 0x10 +#define PAR97_POWER 0xf8 + +/* ---------------------------------------------------------------------- */ +/* + * Information that need to be kept for each board. + */ + +struct baycom_state { + struct hdlcdrv_state hdrv; + + struct pardevice *pdev; + unsigned int options; + + struct modem_state { + short arb_divider; + unsigned char flags; + unsigned int shreg; + struct modem_state_par96 { + int dcd_count; + unsigned int dcd_shreg; + unsigned long descram; + unsigned long scram; + } par96; + } 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 */ +} + +/* --------------------------------------------------------------------- */ +/* + * ===================== PAR96 specific routines ========================= + */ + +#define PAR96_DESCRAM_TAP1 0x20000 +#define PAR96_DESCRAM_TAP2 0x01000 +#define PAR96_DESCRAM_TAP3 0x00001 + +#define PAR96_DESCRAM_TAPSH1 17 +#define PAR96_DESCRAM_TAPSH2 12 +#define PAR96_DESCRAM_TAPSH3 0 + +#define PAR96_SCRAM_TAP1 0x20000 /* X^17 */ +#define PAR96_SCRAM_TAPN 0x00021 /* X^0+X^5 */ + +/* --------------------------------------------------------------------- */ + +static inline void par96_tx(struct net_device *dev, struct baycom_state *bc) +{ + int i; + unsigned int data = hdlcdrv_getbits(&bc->hdrv); + struct parport *pp = bc->pdev->port; + + for(i = 0; i < PAR96_BURSTBITS; i++, data >>= 1) { + unsigned char val = PAR97_POWER; + bc->modem.par96.scram = ((bc->modem.par96.scram << 1) | + (bc->modem.par96.scram & 1)); + if (!(data & 1)) + bc->modem.par96.scram ^= 1; + if (bc->modem.par96.scram & (PAR96_SCRAM_TAP1 << 1)) + bc->modem.par96.scram ^= + (PAR96_SCRAM_TAPN << 1); + if (bc->modem.par96.scram & (PAR96_SCRAM_TAP1 << 2)) + val |= PAR96_TXBIT; + pp->ops->write_data(pp, val); + pp->ops->write_data(pp, val | PAR96_BURST); + } +} + +/* --------------------------------------------------------------------- */ + +static inline void par96_rx(struct net_device *dev, struct baycom_state *bc) +{ + int i; + unsigned int data, mask, mask2, descx; + struct parport *pp = bc->pdev->port; + + /* + * do receiver; differential decode and descramble on the fly + */ + for(data = i = 0; i < PAR96_BURSTBITS; i++) { + bc->modem.par96.descram = (bc->modem.par96.descram << 1); + if (pp->ops->read_status(pp) & PAR96_RXBIT) + bc->modem.par96.descram |= 1; + descx = bc->modem.par96.descram ^ + (bc->modem.par96.descram >> 1); + /* now the diff decoded data is inverted in descram */ + pp->ops->write_data(pp, PAR97_POWER | PAR96_PTT); + descx ^= ((descx >> PAR96_DESCRAM_TAPSH1) ^ + (descx >> PAR96_DESCRAM_TAPSH2)); + data >>= 1; + if (!(descx & 1)) + data |= 0x8000; + pp->ops->write_data(pp, PAR97_POWER | PAR96_PTT | PAR96_BURST); + } + hdlcdrv_putbits(&bc->hdrv, data); + /* + * do DCD algorithm + */ + if (bc->options & BAYCOM_OPTIONS_SOFTDCD) { + bc->modem.par96.dcd_shreg = (bc->modem.par96.dcd_shreg >> 16) + | (data << 16); + /* search for flags and set the dcd counter appropriately */ + for(mask = 0x1fe00, mask2 = 0xfc00, i = 0; + i < PAR96_BURSTBITS; i++, mask <<= 1, mask2 <<= 1) + if ((bc->modem.par96.dcd_shreg & mask) == mask2) + bc->modem.par96.dcd_count = HDLCDRV_MAXFLEN+4; + /* check for abort/noise sequences */ + for(mask = 0x1fe00, mask2 = 0x1fe00, i = 0; + i < PAR96_BURSTBITS; i++, mask <<= 1, mask2 <<= 1) + if (((bc->modem.par96.dcd_shreg & mask) == mask2) && + (bc->modem.par96.dcd_count >= 0)) + bc->modem.par96.dcd_count -= HDLCDRV_MAXFLEN-10; + /* decrement and set the dcd variable */ + if (bc->modem.par96.dcd_count >= 0) + bc->modem.par96.dcd_count -= 2; + hdlcdrv_setdcd(&bc->hdrv, bc->modem.par96.dcd_count > 0); + } else { + hdlcdrv_setdcd(&bc->hdrv, !!(pp->ops->read_status(pp) & PAR96_DCD)); + } +} + +/* --------------------------------------------------------------------- */ + +static void par96_interrupt(void *dev_id) +{ + struct net_device *dev = dev_id; + struct baycom_state *bc = netdev_priv(dev); + + baycom_int_freq(bc); + /* + * check if transmitter active + */ + if (hdlcdrv_ptt(&bc->hdrv)) + par96_tx(dev, bc); + else { + par96_rx(dev, bc); + if (--bc->modem.arb_divider <= 0) { + bc->modem.arb_divider = 6; + local_irq_enable(); + hdlcdrv_arbitrate(dev, &bc->hdrv); + } + } + local_irq_enable(); + hdlcdrv_transmitter(dev, &bc->hdrv); + hdlcdrv_receiver(dev, &bc->hdrv); + local_irq_disable(); +} + +/* --------------------------------------------------------------------- */ + +static void par96_wakeup(void *handle) +{ + struct net_device *dev = (struct net_device *)handle; + struct baycom_state *bc = netdev_priv(dev); + + printk(KERN_DEBUG "baycom_par: %s: why am I being woken up?\n", dev->name); + if (!parport_claim(bc->pdev)) + printk(KERN_DEBUG "baycom_par: %s: I'm broken.\n", dev->name); +} + +/* --------------------------------------------------------------------- */ + +static int par96_open(struct net_device *dev) +{ + struct baycom_state *bc = netdev_priv(dev); + struct pardev_cb par_cb; + struct parport *pp; + int i; + + if (!dev || !bc) + return -ENXIO; + pp = parport_find_base(dev->base_addr); + if (!pp) { + printk(KERN_ERR "baycom_par: parport at 0x%lx unknown\n", dev->base_addr); + return -ENXIO; + } + if (pp->irq < 0) { + printk(KERN_ERR "baycom_par: parport at 0x%lx has no irq\n", pp->base); + parport_put_port(pp); + return -ENXIO; + } + if ((~pp->modes) & (PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT)) { + printk(KERN_ERR "baycom_par: parport at 0x%lx cannot be used\n", pp->base); + parport_put_port(pp); + return -ENXIO; + } + memset(&bc->modem, 0, sizeof(bc->modem)); + bc->hdrv.par.bitrate = 9600; + memset(&par_cb, 0, sizeof(par_cb)); + par_cb.wakeup = par96_wakeup; + par_cb.irq_func = par96_interrupt; + 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 "baycom_par: cannot register parport at 0x%lx\n", dev->base_addr); + return -ENXIO; + } + if (parport_claim(bc->pdev)) { + printk(KERN_ERR "baycom_par: parport at 0x%lx busy\n", pp->base); + parport_unregister_device(bc->pdev); + return -EBUSY; + } + pp = bc->pdev->port; + dev->irq = pp->irq; + pp->ops->data_forward(pp); + bc->hdrv.par.bitrate = 9600; + pp->ops->write_data(pp, PAR96_PTT | PAR97_POWER); /* switch off PTT */ + pp->ops->enable_irq(pp); + printk(KERN_INFO "%s: par96 at iobase 0x%lx irq %u options 0x%x\n", + bc_drvname, dev->base_addr, dev->irq, bc->options); + return 0; +} + +/* --------------------------------------------------------------------- */ + +static int par96_close(struct net_device *dev) +{ + struct baycom_state *bc = netdev_priv(dev); + struct parport *pp; + + if (!dev || !bc) + return -EINVAL; + pp = bc->pdev->port; + /* disable interrupt */ + pp->ops->disable_irq(pp); + /* switch off PTT */ + pp->ops->write_data(pp, PAR96_PTT | PAR97_POWER); + parport_release(bc->pdev); + parport_unregister_device(bc->pdev); + printk(KERN_INFO "%s: close par96 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, void __user *data, + struct hdlcdrv_ioctl *hi, int cmd); + +/* --------------------------------------------------------------------- */ + +static const struct hdlcdrv_ops par96_ops = { + .drvname = bc_drvname, + .drvinfo = bc_drvinfo, + .open = par96_open, + .close = par96_close, + .ioctl = baycom_ioctl +}; + +/* --------------------------------------------------------------------- */ + +static int baycom_setmode(struct baycom_state *bc, const char *modestr) +{ + if (!strncmp(modestr, "picpar", 6)) + bc->options = 0; + else if (!strncmp(modestr, "par96", 5)) + bc->options = BAYCOM_OPTIONS_SOFTDCD; + else + bc->options = !!strchr(modestr, '*'); + return 0; +} + +/* --------------------------------------------------------------------- */ + +static int baycom_ioctl(struct net_device *dev, void __user *data, + 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: + strcpy(hi->data.modename, bc->options ? "par96" : "picpar"); + if (copy_to_user(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, "par96,picpar"); + if (copy_to_user(data, hi, sizeof(struct hdlcdrv_ioctl))) + return -EFAULT; + return 0; + + case HDLCDRVCTL_MODEMPARMASK: + return HDLCDRV_PARMASK_IOBASE; + + } + + if (copy_from_user(&bi, 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(data, &bi, sizeof(bi))) + return -EFAULT; + return 0; + +} + +/* --------------------------------------------------------------------- */ + +/* + * command line settable parameters + */ +static char *mode[NR_PORTS] = { "picpar", }; +static int iobase[NR_PORTS] = { 0x378, }; + +module_param_array(mode, charp, NULL, 0); +MODULE_PARM_DESC(mode, "baycom operating mode; eg. par96 or picpar"); +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 par96 and picpar amateur radio modem driver"); +MODULE_LICENSE("GPL"); + +/* --------------------------------------------------------------------- */ + +static int baycom_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_par_driver = { + .name = "bcp", + .probe = baycom_par_probe, + .devmodel = true, +}; + +static int __init init_baycompar(void) +{ + int i, found = 0, ret; + char set_hw = 1; + + printk(bc_drvinfo); + + ret = parport_register_driver(&baycom_par_driver); + if (ret) + return ret; + + /* + * register net devices + */ + for (i = 0; i < NR_PORTS; i++) { + struct net_device *dev; + struct baycom_state *bc; + char ifname[IFNAMSIZ]; + + sprintf(ifname, "bcp%d", i); + + if (!mode[i]) + set_hw = 0; + if (!set_hw) + iobase[i] = 0; + + dev = hdlcdrv_register(&par96_ops, + sizeof(struct baycom_state), + ifname, iobase[i], 0, 0); + if (IS_ERR(dev)) + break; + + bc = netdev_priv(dev); + if (set_hw && baycom_setmode(bc, mode[i])) + set_hw = 0; + found++; + baycom_device[i] = dev; + } + + if (!found) { + parport_unregister_driver(&baycom_par_driver); + return -ENXIO; + } + return 0; +} + +static void __exit cleanup_baycompar(void) +{ + int i; + + for(i = 0; i < NR_PORTS; i++) { + struct net_device *dev = baycom_device[i]; + + if (dev) + hdlcdrv_unregister(dev); + } + parport_unregister_driver(&baycom_par_driver); +} + +module_init(init_baycompar); +module_exit(cleanup_baycompar); + +/* --------------------------------------------------------------------- */ + +#ifndef MODULE + +/* + * format: baycom_par=io,mode + * mode: par96,picpar + */ + +static int __init baycom_par_setup(char *str) +{ + static unsigned nr_dev; + 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_par=", baycom_par_setup); + +#endif /* MODULE */ +/* --------------------------------------------------------------------- */ |