// 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 This modem is no longer available (at least * from Baycom) and has been replaced by the PICPAR modem (see below).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, struct ifreq *ifr, 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, 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: strcpy(hi->data.modename, bc->options ? "par96" : "picpar"); 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, "par96,picpar"); if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl))) return -EFAULT; return 0; case HDLCDRVCTL_MODEMPARMASK: return HDLCDRV_PARMASK_IOBASE; } 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] = { "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 */ /* --------------------------------------------------------------------- */