// SPDX-License-Identifier: GPL-2.0-or-later /*****************************************************************************/ /* * baycom_ser_fdx.c -- baycom ser12 fullduplex 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 * * 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 #include #include #include #include #include #include #include #include #include #include #include #include /* --------------------------------------------------------------------- */ #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) */ } static __inline__ void ser12_rx(struct net_device *dev, struct baycom_state *bc, struct timespec64 *ts, 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 + ts->tv_nsec / NSEC_PER_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 timespec64 ts; 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 */ ktime_get_ts64(&ts); 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, &ts, 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_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 const 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_hw_array(iobase, int, ioport, NULL, 0); MODULE_PARM_DESC(iobase, "baycom io base address"); module_param_hw_array(irq, int, irq, 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 */ /* --------------------------------------------------------------------- */