/* $NetBSD: com.c,v 1.108 1997/08/27 18:00:13 is Exp $ */ /*- * Copyright (c) 1993, 1994, 1995, 1996, 1997 * Charles M. Hannum. All rights reserved. * * Interrupt processing and hardware flow control partly based on code from * Onno van der Linden and Gordon Ross. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Charles M. Hannum. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1991 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)com.c 7.5 (Berkeley) 5/16/91 */ /* * COM driver, uses National Semiconductor NS16450/NS16550AF UART */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef COM_HAYESP #include #endif #define com_lcr com_cfcr #include #include "com.h" #ifdef COM_HAYESP int comprobeHAYESP __P((bus_space_handle_t hayespioh, struct com_softc *sc)); #endif #if defined(DDB) || defined(KGDB) static void com_enable_debugport __P((struct com_softc *)); #endif void com_attach_subr __P((struct com_softc *sc)); void comdiag __P((void *)); int comspeed __P((long)); static u_char cflag2lcr __P((tcflag_t)); int comparam __P((struct tty *, struct termios *)); void comstart __P((struct tty *)); void comstop __P((struct tty *, int)); #ifdef __GENERIC_SOFT_INTERRUPTS void comsoft __P((void *)); #else #ifndef alpha void comsoft __P((void)); #else void comsoft __P((void *)); #endif #endif int comhwiflow __P((struct tty *, int)); void com_loadchannelregs __P((struct com_softc *)); void com_hwiflow __P((struct com_softc *)); void com_break __P((struct com_softc *, int)); void com_modem __P((struct com_softc *, int)); void com_iflush __P((struct com_softc *)); int com_common_getc __P((bus_space_tag_t, bus_space_handle_t)); void com_common_putc __P((bus_space_tag_t, bus_space_handle_t, int)); /* XXX: These belong elsewhere */ cdev_decl(com); bdev_decl(com); int comcngetc __P((dev_t)); void comcnputc __P((dev_t, int)); void comcnpollc __P((dev_t, int)); #define integrate static inline integrate void comrxint __P((struct com_softc *, struct tty *)); integrate void comtxint __P((struct com_softc *, struct tty *)); integrate void commsrint __P((struct com_softc *, struct tty *)); integrate void com_schedrx __P((struct com_softc *)); struct cfdriver com_cd = { NULL, "com", DV_TTY }; static int comconsaddr; static bus_space_tag_t comconstag; static bus_space_handle_t comconsioh; static int comconsattached; static int comconsrate; static tcflag_t comconscflag; #ifndef __GENERIC_SOFT_INTERRUPTS #ifdef alpha volatile int com_softintr_scheduled; #endif #endif #ifdef KGDB #include static int com_kgdb_addr; static bus_space_tag_t com_kgdb_iot; static bus_space_handle_t com_kgdb_ioh; static int com_kgdb_attached; int com_kgdb_getc __P((void *)); void com_kgdb_putc __P((void *, int)); #endif /* KGDB */ #define COMUNIT(x) (minor(x)) int comspeed(speed) long speed; { #define divrnd(n, q) (((n)*2/(q)+1)/2) /* divide and round off */ int x, err; #if 0 if (speed == 0) return (0); #endif if (speed <= 0) return (-1); x = divrnd((COM_FREQ / 16), speed); if (x <= 0) return (-1); err = divrnd((COM_FREQ / 16) * 1000, speed * x) - 1000; if (err < 0) err = -err; if (err > COM_TOLERANCE) return (-1); return (x); #undef divrnd(n, q) } #ifdef COM_DEBUG int com_debug = 0; void comstatus __P((struct com_softc *, char *)); void comstatus(sc, str) struct com_softc *sc; char *str; { struct tty *tp = sc->sc_tty; printf("%s: %s %sclocal %sdcd %sts_carr_on %sdtr %stx_stopped\n", sc->sc_dev.dv_xname, str, ISSET(tp->t_cflag, CLOCAL) ? "+" : "-", ISSET(sc->sc_msr, MSR_DCD) ? "+" : "-", ISSET(tp->t_state, TS_CARR_ON) ? "+" : "-", ISSET(sc->sc_mcr, MCR_DTR) ? "+" : "-", sc->sc_tx_stopped ? "+" : "-"); printf("%s: %s %scrtscts %scts %sts_ttstop %srts %xrx_flags\n", sc->sc_dev.dv_xname, str, ISSET(tp->t_cflag, CRTSCTS) ? "+" : "-", ISSET(sc->sc_msr, MSR_CTS) ? "+" : "-", ISSET(tp->t_state, TS_TTSTOP) ? "+" : "-", ISSET(sc->sc_mcr, MCR_RTS) ? "+" : "-", sc->sc_rx_flags); } #endif int comprobe1(iot, ioh, iobase) bus_space_tag_t iot; bus_space_handle_t ioh; int iobase; { /* force access to id reg */ bus_space_write_1(iot, ioh, com_lcr, 0); bus_space_write_1(iot, ioh, com_iir, 0); if (bus_space_read_1(iot, ioh, com_iir) & 0x38) return (0); return (1); } #ifdef COM_HAYESP int comprobeHAYESP(hayespioh, sc) bus_space_handle_t hayespioh; struct com_softc *sc; { char val, dips; int combaselist[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 }; bus_space_tag_t iot = sc->sc_iot; /* * Hayes ESP cards have two iobases. One is for compatibility with * 16550 serial chips, and at the same ISA PC base addresses. The * other is for ESP-specific enhanced features, and lies at a * different addressing range entirely (0x140, 0x180, 0x280, or 0x300). */ /* Test for ESP signature */ if ((bus_space_read_1(iot, hayespioh, 0) & 0xf3) == 0) return (0); /* * ESP is present at ESP enhanced base address; unknown com port */ /* Get the dip-switch configurations */ bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETDIPS); dips = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1); /* Determine which com port this ESP card services: bits 0,1 of */ /* dips is the port # (0-3); combaselist[val] is the com_iobase */ if (sc->sc_iobase != combaselist[dips & 0x03]) return (0); printf(": ESP"); /* Check ESP Self Test bits. */ /* Check for ESP version 2.0: bits 4,5,6 == 010 */ bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_GETTEST); val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS1); /* Clear reg1 */ val = bus_space_read_1(iot, hayespioh, HAYESP_STATUS2); if ((val & 0x70) < 0x20) { printf("-old (%o)", val & 0x70); /* we do not support the necessary features */ return (0); } /* Check for ability to emulate 16550: bit 8 == 1 */ if ((dips & 0x80) == 0) { printf(" slave"); /* XXX Does slave really mean no 16550 support?? */ return (0); } /* * If we made it this far, we are a full-featured ESP v2.0 (or * better), at the correct com port address. */ SET(sc->sc_hwflags, COM_HW_HAYESP); printf(", 1024 byte fifo\n"); return (1); } #endif #if defined(DDB) || defined(KGDB) static void com_enable_debugport(sc) struct com_softc *sc; { int s; /* Turn on line break interrupt, set carrier. */ s = splserial(); sc->sc_ier = IER_ERXRDY; bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier); SET(sc->sc_mcr, MCR_DTR | MCR_RTS); bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_mcr, sc->sc_mcr); splx(s); } #endif void com_attach_subr(sc) struct com_softc *sc; { int iobase = sc->sc_iobase; bus_space_tag_t iot = sc->sc_iot; bus_space_handle_t ioh = sc->sc_ioh; #ifdef COM_HAYESP int hayesp_ports[] = { 0x140, 0x180, 0x280, 0x300, 0 }; int *hayespp; #endif if (iot == comconstag && iobase == comconsaddr) { comconsattached = 1; /* Make sure the console is always "hardwired". */ delay(1000); /* wait for output to finish */ SET(sc->sc_hwflags, COM_HW_CONSOLE); SET(sc->sc_swflags, TIOCFLAG_SOFTCAR); } #ifdef COM_HAYESP /* Look for a Hayes ESP board. */ for (hayespp = hayesp_ports; *hayespp != 0; hayespp++) { bus_space_handle_t hayespioh; #define HAYESP_NPORTS 8 /* XXX XXX XXX ??? ??? ??? */ if (bus_space_map(iot, *hayespp, HAYESP_NPORTS, 0, &hayespioh)) continue; if (comprobeHAYESP(hayespioh, sc)) { sc->sc_hayespioh = hayespioh; sc->sc_fifolen = 1024; /* Set 16550 compatibility mode */ bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_SETMODE); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_MODE_FIFO|HAYESP_MODE_RTS| HAYESP_MODE_SCALE); /* Set RTS/CTS flow control */ bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_SETFLOWTYPE); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_FLOW_RTS); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_FLOW_CTS); /* Set flow control levels */ bus_space_write_1(iot, hayespioh, HAYESP_CMD1, HAYESP_SETRXFLOW); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_HIBYTE(HAYESP_RXHIWMARK)); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_LOBYTE(HAYESP_RXHIWMARK)); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_HIBYTE(HAYESP_RXLOWMARK)); bus_space_write_1(iot, hayespioh, HAYESP_CMD2, HAYESP_LOBYTE(HAYESP_RXLOWMARK)); break; } bus_space_unmap(iot, hayespioh, HAYESP_NPORTS); } /* No ESP; look for other things. */ if (*hayespp == 0) { #endif sc->sc_fifolen = 1; /* look for a NS 16550AF UART with FIFOs */ bus_space_write_1(iot, ioh, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_14); delay(100); if (ISSET(bus_space_read_1(iot, ioh, com_iir), IIR_FIFO_MASK) == IIR_FIFO_MASK) if (ISSET(bus_space_read_1(iot, ioh, com_fifo), FIFO_TRIGGER_14) == FIFO_TRIGGER_14) { SET(sc->sc_hwflags, COM_HW_FIFO); printf(": ns16550a, working fifo\n"); sc->sc_fifolen = 16; } else printf(": ns16550, broken fifo\n"); else printf(": ns8250 or ns16450, no fifo\n"); bus_space_write_1(iot, ioh, com_fifo, 0); #ifdef COM_HAYESP } #endif if (!ISSET(sc->sc_hwflags, COM_HW_NOIEN)) SET(sc->sc_mcr, MCR_IENABLE); if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) { int maj; /* locate the major number */ for (maj = 0; maj < nchrdev; maj++) if (cdevsw[maj].d_open == comopen) break; cn_tab->cn_dev = makedev(maj, sc->sc_dev.dv_unit); #ifdef DDB com_enable_debugport(sc); #endif printf("%s: console\n", sc->sc_dev.dv_xname); } #ifdef KGDB /* * Allow kgdb to "take over" this port. If this is * the kgdb device, it has exclusive use. */ if (iot == com_kgdb_iot && iobase == com_kgdb_addr) { com_kgdb_attached = 1; SET(sc->sc_hwflags, COM_HW_KGDB); com_enable_debugport(sc); printf("%s: kgdb\n", sc->sc_dev.dv_xname); } #endif #ifdef __GENERIC_SOFT_INTERRUPTS sc->sc_si = softintr_establish(IPL_SOFTSERIAL, comsoft, sc); #endif } int comopen(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { int unit = COMUNIT(dev); struct com_softc *sc; struct tty *tp; int s, s2; int error = 0; if (unit >= com_cd.cd_ndevs) return (ENXIO); sc = com_cd.cd_devs[unit]; if (!sc) return (ENXIO); #ifdef KGDB /* * If this is the kgdb port, no other use is permitted. */ if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) return (EBUSY); #endif if (!sc->sc_tty) { tp = sc->sc_tty = ttymalloc(); tty_attach(tp); } else tp = sc->sc_tty; if (ISSET(tp->t_state, TS_ISOPEN) && ISSET(tp->t_state, TS_XCLUDE) && p->p_ucred->cr_uid != 0) return (EBUSY); s = spltty(); /* We need to set this early for the benefit of comsoft(). */ SET(tp->t_state, TS_WOPEN); /* * Do the following iff this is a first open. */ if (!ISSET(tp->t_state, TS_ISOPEN)) { struct termios t; /* Turn on interrupts. */ sc->sc_ier = IER_ERXRDY | IER_ERLS | IER_EMSC; bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier); /* Fetch the current modem control status, needed later. */ sc->sc_msr = bus_space_read_1(sc->sc_iot, sc->sc_ioh, com_msr); /* Add some entry points needed by the tty layer. */ tp->t_oproc = comstart; tp->t_param = comparam; tp->t_hwiflow = comhwiflow; tp->t_dev = dev; /* * Initialize the termios status to the defaults. Add in the * sticky bits from TIOCSFLAGS. */ t.c_ispeed = 0; if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) { t.c_ospeed = comconsrate; t.c_cflag = comconscflag; } else { t.c_ospeed = TTYDEF_SPEED; t.c_cflag = TTYDEF_CFLAG; } if (ISSET(sc->sc_swflags, TIOCFLAG_CLOCAL)) SET(t.c_cflag, CLOCAL); if (ISSET(sc->sc_swflags, TIOCFLAG_CRTSCTS)) SET(t.c_cflag, CRTSCTS); if (ISSET(sc->sc_swflags, TIOCFLAG_MDMBUF)) SET(t.c_cflag, MDMBUF); tp->t_iflag = TTYDEF_IFLAG; tp->t_oflag = TTYDEF_OFLAG; tp->t_lflag = TTYDEF_LFLAG; ttychars(tp); (void) comparam(tp, &t); ttsetwater(tp); s2 = splserial(); /* * Turn on DTR. We must always do this, even if carrier is not * present, because otherwise we'd have to use TIOCSDTR * immediately after setting CLOCAL. We will drop DTR only on * the next high-low transition of DCD, or by explicit request. */ com_modem(sc, 1); /* Clear the input ring, and unblock. */ sc->sc_rbput = sc->sc_rbget = 0; sc->sc_rbavail = RXBUFSIZE; com_iflush(sc); CLR(sc->sc_rx_flags, RX_ANY_BLOCK); com_hwiflow(sc); #ifdef COM_DEBUG if (com_debug) comstatus(sc, "comopen "); #endif splx(s2); } error = 0; /* If we're doing a blocking open... */ if (!ISSET(flag, O_NONBLOCK)) /* ...then wait for carrier. */ while (!ISSET(tp->t_state, TS_CARR_ON) && !ISSET(tp->t_cflag, CLOCAL | MDMBUF)) { error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH, ttopen, 0); if (error) { /* * If the open was interrupted and nobody * else has the device open, then hang up. */ if (!ISSET(tp->t_state, TS_ISOPEN)) { com_modem(sc, 0); CLR(tp->t_state, TS_WOPEN); ttwakeup(tp); } break; } SET(tp->t_state, TS_WOPEN); } splx(s); if (error == 0) error = (*linesw[tp->t_line].l_open)(dev, tp); return (error); } int comclose(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { int unit = COMUNIT(dev); struct com_softc *sc = com_cd.cd_devs[unit]; struct tty *tp = sc->sc_tty; int s; /* XXX This is for cons.c. */ if (!ISSET(tp->t_state, TS_ISOPEN)) return (0); (*linesw[tp->t_line].l_close)(tp, flag); ttyclose(tp); /* If we were asserting flow control, then deassert it. */ SET(sc->sc_rx_flags, RX_IBUF_BLOCKED); com_hwiflow(sc); /* Clear any break condition set with TIOCSBRK. */ com_break(sc, 0); /* * Hang up if necessary. Wait a bit, so the other side has time to * notice even if we immediately open the port again. */ if (ISSET(tp->t_cflag, HUPCL)) { com_modem(sc, 0); (void) tsleep(sc, TTIPRI, ttclos, hz); } s = splserial(); /* Turn off interrupts. */ #ifdef DDB if(ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) sc->sc_ier = IER_ERXRDY; /* interrupt on break */ else #else sc->sc_ier = 0; #endif bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier); splx(s); return (0); } int comread(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)]; struct tty *tp = sc->sc_tty; return ((*linesw[tp->t_line].l_read)(tp, uio, flag)); } int comwrite(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)]; struct tty *tp = sc->sc_tty; return ((*linesw[tp->t_line].l_write)(tp, uio, flag)); } struct tty * comtty(dev) dev_t dev; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(dev)]; struct tty *tp = sc->sc_tty; return (tp); } int comioctl(dev, cmd, data, flag, p) dev_t dev; u_long cmd; caddr_t data; int flag; struct proc *p; { int unit = COMUNIT(dev); struct com_softc *sc = com_cd.cd_devs[unit]; struct tty *tp = sc->sc_tty; int error; error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p); if (error >= 0) return (error); error = ttioctl(tp, cmd, data, flag, p); if (error >= 0) return (error); switch (cmd) { case TIOCSBRK: com_break(sc, 1); break; case TIOCCBRK: com_break(sc, 0); break; case TIOCSDTR: com_modem(sc, 1); break; case TIOCCDTR: com_modem(sc, 0); break; case TIOCGFLAGS: *(int *)data = sc->sc_swflags; break; case TIOCSFLAGS: error = suser(p->p_ucred, &p->p_acflag); if (error) return (error); sc->sc_swflags = *(int *)data; break; case TIOCMSET: case TIOCMBIS: case TIOCMBIC: case TIOCMGET: default: return (ENOTTY); } #ifdef COM_DEBUG if (com_debug) comstatus(sc, "comioctl "); #endif return (0); } integrate void com_schedrx(sc) struct com_softc *sc; { sc->sc_rx_ready = 1; /* Wake up the poller. */ #ifdef __GENERIC_SOFT_INTERRUPTS softintr_schedule(sc->sc_si); #else #ifndef alpha setsoftserial(); #else if (!com_softintr_scheduled) { com_softintr_scheduled = 1; timeout(comsoft, NULL, 1); } #endif #endif } void com_break(sc, onoff) struct com_softc *sc; int onoff; { int s; s = splserial(); if (onoff) SET(sc->sc_lcr, LCR_SBREAK); else CLR(sc->sc_lcr, LCR_SBREAK); if (!sc->sc_heldchange) { if (sc->sc_tx_busy) { sc->sc_heldtbc = sc->sc_tbc; sc->sc_tbc = 0; sc->sc_heldchange = 1; } else com_loadchannelregs(sc); } splx(s); } void com_modem(sc, onoff) struct com_softc *sc; int onoff; { int s; s = splserial(); if (onoff) SET(sc->sc_mcr, sc->sc_mcr_dtr); else CLR(sc->sc_mcr, sc->sc_mcr_dtr); if (!sc->sc_heldchange) { if (sc->sc_tx_busy) { sc->sc_heldtbc = sc->sc_tbc; sc->sc_tbc = 0; sc->sc_heldchange = 1; } else com_loadchannelregs(sc); } splx(s); } static u_char cflag2lcr(cflag) tcflag_t cflag; { u_char lcr = 0; switch (ISSET(cflag, CSIZE)) { case CS5: SET(lcr, LCR_5BITS); break; case CS6: SET(lcr, LCR_6BITS); break; case CS7: SET(lcr, LCR_7BITS); break; case CS8: SET(lcr, LCR_8BITS); break; } if (ISSET(cflag, PARENB)) { SET(lcr, LCR_PENAB); if (!ISSET(cflag, PARODD)) SET(lcr, LCR_PEVEN); } if (ISSET(cflag, CSTOPB)) SET(lcr, LCR_STOPB); return(lcr); } int comparam(tp, t) struct tty *tp; struct termios *t; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)]; int ospeed = comspeed(t->c_ospeed); u_char lcr; int s; /* check requested parameters */ if (ospeed < 0) return (EINVAL); if (t->c_ispeed && t->c_ispeed != t->c_ospeed) return (EINVAL); lcr = ISSET(sc->sc_lcr, LCR_SBREAK) | cflag2lcr(t->c_cflag); s = splserial(); sc->sc_lcr = lcr; /* * For the console, always force CLOCAL and !HUPCL, so that the port * is always active. */ if (ISSET(sc->sc_swflags, TIOCFLAG_SOFTCAR) || ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) { SET(t->c_cflag, CLOCAL); CLR(t->c_cflag, HUPCL); } /* * If we're not in a mode that assumes a connection is present, then * ignore carrier changes. */ if (ISSET(t->c_cflag, CLOCAL | MDMBUF)) sc->sc_msr_dcd = 0; else sc->sc_msr_dcd = MSR_DCD; /* * Set the flow control pins depending on the current flow control * mode. */ if (ISSET(t->c_cflag, CRTSCTS)) { sc->sc_mcr_dtr = MCR_DTR; sc->sc_mcr_rts = MCR_RTS; sc->sc_msr_cts = MSR_CTS; sc->sc_r_hiwat = RXHIWAT; sc->sc_r_lowat = RXLOWAT; } else if (ISSET(t->c_cflag, MDMBUF)) { /* * For DTR/DCD flow control, make sure we don't toggle DTR for * carrier detection. */ sc->sc_mcr_dtr = 0; sc->sc_mcr_rts = MCR_DTR; sc->sc_msr_cts = MSR_DCD; sc->sc_r_hiwat = RXHIWAT; sc->sc_r_lowat = RXLOWAT; } else { /* * If no flow control, then always set RTS. This will make * the other side happy if it mistakenly thinks we're doing * RTS/CTS flow control. */ sc->sc_mcr_dtr = MCR_DTR | MCR_RTS; sc->sc_mcr_rts = 0; sc->sc_msr_cts = 0; sc->sc_r_hiwat = 0; sc->sc_r_lowat = 0; if (ISSET(sc->sc_mcr, MCR_DTR)) SET(sc->sc_mcr, MCR_RTS); else CLR(sc->sc_mcr, MCR_RTS); } sc->sc_msr_mask = sc->sc_msr_cts | sc->sc_msr_dcd; #if 0 if (ospeed == 0) CLR(sc->sc_mcr, sc->sc_mcr_dtr); else SET(sc->sc_mcr, sc->sc_mcr_dtr); #endif sc->sc_dlbl = ospeed; sc->sc_dlbh = ospeed >> 8; /* * Set the FIFO threshold based on the receive speed. * * * If it's a low speed, it's probably a mouse or some other * interactive device, so set the threshold low. * * If it's a high speed, trim the trigger level down to prevent * overflows. * * Otherwise set it a bit higher. */ if (ISSET(sc->sc_hwflags, COM_HW_HAYESP)) sc->sc_fifo = FIFO_DMA_MODE | FIFO_ENABLE | FIFO_TRIGGER_8; else if (ISSET(sc->sc_hwflags, COM_HW_FIFO)) sc->sc_fifo = FIFO_ENABLE | (t->c_ospeed <= 1200 ? FIFO_TRIGGER_1 : t->c_ospeed <= 38400 ? FIFO_TRIGGER_8 : FIFO_TRIGGER_4); else sc->sc_fifo = 0; /* and copy to tty */ tp->t_ispeed = 0; tp->t_ospeed = t->c_ospeed; tp->t_cflag = t->c_cflag; if (!sc->sc_heldchange) { if (sc->sc_tx_busy) { sc->sc_heldtbc = sc->sc_tbc; sc->sc_tbc = 0; sc->sc_heldchange = 1; } else com_loadchannelregs(sc); } splx(s); /* * Update the tty layer's idea of the carrier bit, in case we changed * CLOCAL or MDMBUF. We don't hang up here; we only do that if we * lose carrier while carrier detection is on. */ (void) (*linesw[tp->t_line].l_modem)(tp, ISSET(sc->sc_msr, MSR_DCD)); #ifdef COM_DEBUG if (com_debug) comstatus(sc, "comparam "); #endif /* Block or unblock as needed. */ if (!ISSET(t->c_cflag, CHWFLOW)) { if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) { CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED); com_schedrx(sc); } if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED)) { CLR(sc->sc_rx_flags, RX_TTY_BLOCKED|RX_IBUF_BLOCKED); com_hwiflow(sc); } if (sc->sc_tx_stopped) { sc->sc_tx_stopped = 0; comstart(tp); } } else { /* XXXXX FIX ME */ #if 0 commsrint(sc, tp); #endif } return (0); } void com_iflush(sc) struct com_softc *sc; { bus_space_tag_t iot = sc->sc_iot; bus_space_handle_t ioh = sc->sc_ioh; /* flush any pending I/O */ while (ISSET(bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)) (void) bus_space_read_1(iot, ioh, com_data); } void com_loadchannelregs(sc) struct com_softc *sc; { bus_space_tag_t iot = sc->sc_iot; bus_space_handle_t ioh = sc->sc_ioh; /* XXXXX necessary? */ com_iflush(sc); bus_space_write_1(iot, ioh, com_ier, 0); bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr | LCR_DLAB); bus_space_write_1(iot, ioh, com_dlbl, sc->sc_dlbl); bus_space_write_1(iot, ioh, com_dlbh, sc->sc_dlbh); bus_space_write_1(iot, ioh, com_lcr, sc->sc_lcr); bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active = sc->sc_mcr); bus_space_write_1(iot, ioh, com_fifo, sc->sc_fifo); bus_space_write_1(iot, ioh, com_ier, sc->sc_ier); } int comhwiflow(tp, block) struct tty *tp; int block; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)]; int s; if (sc->sc_mcr_rts == 0) return (0); s = splserial(); if (block) { if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) { SET(sc->sc_rx_flags, RX_TTY_BLOCKED); com_hwiflow(sc); } } else { if (ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) { CLR(sc->sc_rx_flags, RX_TTY_OVERFLOWED); com_schedrx(sc); } if (ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) { CLR(sc->sc_rx_flags, RX_TTY_BLOCKED); com_hwiflow(sc); } } splx(s); return (1); } /* * (un)block input via hw flowcontrol */ void com_hwiflow(sc) struct com_softc *sc; { bus_space_tag_t iot = sc->sc_iot; bus_space_handle_t ioh = sc->sc_ioh; if (sc->sc_mcr_rts == 0) return; if (ISSET(sc->sc_rx_flags, RX_ANY_BLOCK)) { CLR(sc->sc_mcr, sc->sc_mcr_rts); CLR(sc->sc_mcr_active, sc->sc_mcr_rts); } else { SET(sc->sc_mcr, sc->sc_mcr_rts); SET(sc->sc_mcr_active, sc->sc_mcr_rts); } bus_space_write_1(iot, ioh, com_mcr, sc->sc_mcr_active); } void comstart(tp) struct tty *tp; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)]; bus_space_tag_t iot = sc->sc_iot; bus_space_handle_t ioh = sc->sc_ioh; int s; s = spltty(); if (ISSET(tp->t_state, TS_BUSY)) goto out; if (ISSET(tp->t_state, TS_TIMEOUT | TS_TTSTOP)) goto stopped; if (sc->sc_tx_stopped) goto stopped; if (tp->t_outq.c_cc <= tp->t_lowat) { if (ISSET(tp->t_state, TS_ASLEEP)) { CLR(tp->t_state, TS_ASLEEP); wakeup(&tp->t_outq); } selwakeup(&tp->t_wsel); if (tp->t_outq.c_cc == 0) goto stopped; } /* Grab the first contiguous region of buffer space. */ { u_char *tba; int tbc; tba = tp->t_outq.c_cf; tbc = ndqb(&tp->t_outq, 0); (void)splserial(); sc->sc_tba = tba; sc->sc_tbc = tbc; } SET(tp->t_state, TS_BUSY); sc->sc_tx_busy = 1; /* Enable transmit completion interrupts if necessary. */ if (!ISSET(sc->sc_ier, IER_ETXRDY)) { SET(sc->sc_ier, IER_ETXRDY); bus_space_write_1(iot, ioh, com_ier, sc->sc_ier); } /* Output the first chunk of the contiguous buffer. */ { int n; n = sc->sc_fifolen; if (n > sc->sc_tbc) n = sc->sc_tbc; bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n); sc->sc_tbc -= n; sc->sc_tba += n; } splx(s); return; stopped: /* Disable transmit completion interrupts if necessary. */ if (ISSET(sc->sc_ier, IER_ETXRDY)) { CLR(sc->sc_ier, IER_ETXRDY); bus_space_write_1(iot, ioh, com_ier, sc->sc_ier); } out: splx(s); return; } /* * Stop output on a line. */ void comstop(tp, flag) struct tty *tp; int flag; { struct com_softc *sc = com_cd.cd_devs[COMUNIT(tp->t_dev)]; int s; s = splserial(); if (ISSET(tp->t_state, TS_BUSY)) { /* Stop transmitting at the next chunk. */ sc->sc_tbc = 0; sc->sc_heldtbc = 0; if (!ISSET(tp->t_state, TS_TTSTOP)) SET(tp->t_state, TS_FLUSH); } splx(s); } void comdiag(arg) void *arg; { struct com_softc *sc = arg; int overflows, floods; int s; s = splserial(); overflows = sc->sc_overflows; sc->sc_overflows = 0; floods = sc->sc_floods; sc->sc_floods = 0; sc->sc_errors = 0; splx(s); log(LOG_WARNING, "%s: %d silo overflow%s, %d ibuf flood%s\n", sc->sc_dev.dv_xname, overflows, overflows == 1 ? "" : "s", floods, floods == 1 ? "" : "s"); } integrate void comrxint(sc, tp) struct com_softc *sc; struct tty *tp; { u_int get, cc, scc; int code; u_char lsr; int s; static int lsrmap[8] = { 0, TTY_PE, TTY_FE, TTY_PE|TTY_FE, TTY_FE, TTY_PE|TTY_FE, TTY_FE, TTY_PE|TTY_FE }; get = sc->sc_rbget; scc = cc = RXBUFSIZE - sc->sc_rbavail; if (cc == RXBUFSIZE) { sc->sc_floods++; if (sc->sc_errors++ == 0) timeout(comdiag, sc, 60 * hz); } while (cc) { lsr = sc->sc_lbuf[get]; if (ISSET(lsr, LSR_OE)) { sc->sc_overflows++; if (sc->sc_errors++ == 0) timeout(comdiag, sc, 60 * hz); } code = sc->sc_rbuf[get] | lsrmap[(lsr & (LSR_BI|LSR_FE|LSR_PE)) >> 2]; if ((*linesw[tp->t_line].l_rint)(code, tp) == -1) { /* * The line discipline's buffer is out of space. */ if (!ISSET(sc->sc_rx_flags, RX_TTY_BLOCKED)) { /* * We're either not using flow control, or the * line discipline didn't tell us to block for * some reason. Either way, we have no way to * know when there's more space available, so * just drop the rest of the data. */ get = (get + cc) & RXBUFMASK; cc = 0; } else { /* * Don't schedule any more receive processing * until the line discipline tells us there's * space available (through comhwiflow()). * Leave the rest of the data in the input * buffer. */ SET(sc->sc_rx_flags, RX_TTY_OVERFLOWED); } break; } get = (get + 1) & RXBUFMASK; cc--; } if (cc != scc) { sc->sc_rbget = get; s = splserial(); cc = sc->sc_rbavail += scc - cc; /* Buffers should be ok again, release possible block. */ if (cc >= sc->sc_r_lowat) { if (ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) { CLR(sc->sc_rx_flags, RX_IBUF_OVERFLOWED); SET(sc->sc_ier, IER_ERXRDY); bus_space_write_1(sc->sc_iot, sc->sc_ioh, com_ier, sc->sc_ier); } if (ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED)) { CLR(sc->sc_rx_flags, RX_IBUF_BLOCKED); com_hwiflow(sc); } } splx(s); } } integrate void comtxint(sc, tp) struct com_softc *sc; struct tty *tp; { CLR(tp->t_state, TS_BUSY); if (ISSET(tp->t_state, TS_FLUSH)) CLR(tp->t_state, TS_FLUSH); else ndflush(&tp->t_outq, (int)(sc->sc_tba - tp->t_outq.c_cf)); (*linesw[tp->t_line].l_start)(tp); } integrate void commsrint(sc, tp) struct com_softc *sc; struct tty *tp; { u_char msr, delta; int s; s = splserial(); msr = sc->sc_msr; delta = sc->sc_msr_delta; sc->sc_msr_delta = 0; splx(s); if (ISSET(delta, sc->sc_msr_dcd)) { /* * Inform the tty layer that carrier detect changed. */ (void) (*linesw[tp->t_line].l_modem)(tp, ISSET(msr, MSR_DCD)); } if (ISSET(delta, sc->sc_msr_cts)) { /* Block or unblock output according to flow control. */ if (ISSET(msr, sc->sc_msr_cts)) { sc->sc_tx_stopped = 0; (*linesw[tp->t_line].l_start)(tp); } else { sc->sc_tx_stopped = 1; } } #ifdef COM_DEBUG if (com_debug) comstatus(sc, "commsrint"); #endif } #ifdef __GENERIC_SOFT_INTERRUPTS void comsoft(arg) void *arg; { struct com_softc *sc = arg; struct tty *tp; { #else void #ifndef alpha comsoft() #else comsoft(arg) void *arg; #endif { struct com_softc *sc; struct tty *tp; int unit; #ifdef alpha int s; s = splsoftserial(); com_softintr_scheduled = 0; #endif for (unit = 0; unit < com_cd.cd_ndevs; unit++) { sc = com_cd.cd_devs[unit]; if (sc == NULL) continue; tp = sc->sc_tty; if (tp == NULL || !ISSET(tp->t_state, TS_ISOPEN | TS_WOPEN)) continue; #endif tp = sc->sc_tty; if (sc->sc_rx_ready) { sc->sc_rx_ready = 0; comrxint(sc, tp); } if (sc->sc_st_check) { sc->sc_st_check = 0; commsrint(sc, tp); } if (sc->sc_tx_done) { sc->sc_tx_done = 0; comtxint(sc, tp); } } #ifndef __GENERIC_SOFT_INTERRUPTS #ifdef alpha splx(s); #endif #endif } int comintr(arg) void *arg; { struct com_softc *sc = arg; bus_space_tag_t iot = sc->sc_iot; bus_space_handle_t ioh = sc->sc_ioh; u_char lsr, iir; u_int put, cc; iir = bus_space_read_1(iot, ioh, com_iir); if (ISSET(iir, IIR_NOPEND)) return (0); put = sc->sc_rbput; cc = sc->sc_rbavail; do { u_char msr, delta; lsr = bus_space_read_1(iot, ioh, com_lsr); #if defined(DDB) || defined(KGDB) if (ISSET(lsr, LSR_BI)) { #ifdef DDB if (ISSET(sc->sc_hwflags, COM_HW_CONSOLE)) { Debugger(); continue; } #endif #ifdef KGDB if (ISSET(sc->sc_hwflags, COM_HW_KGDB)) { kgdb_connect(1); continue; } #endif } #endif /* DDB || KGDB */ if (ISSET(lsr, LSR_RCV_MASK) && !ISSET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED)) { for (; ISSET(lsr, LSR_RCV_MASK) && cc > 0; cc--) { sc->sc_rbuf[put] = bus_space_read_1(iot, ioh, com_data); sc->sc_lbuf[put] = lsr; put = (put + 1) & RXBUFMASK; lsr = bus_space_read_1(iot, ioh, com_lsr); } /* * Current string of incoming characters ended because * no more data was available. Schedule a receive event * if any data was received. Drop any characters that * we couldn't handle. */ sc->sc_rbput = put; sc->sc_rbavail = cc; if (!ISSET(sc->sc_rx_flags, RX_TTY_OVERFLOWED)) sc->sc_rx_ready = 1; /* * See if we are in danger of overflowing a buffer. If * so, use hardware flow control to ease the pressure. */ if (!ISSET(sc->sc_rx_flags, RX_IBUF_BLOCKED) && cc < sc->sc_r_hiwat) { SET(sc->sc_rx_flags, RX_IBUF_BLOCKED); com_hwiflow(sc); } /* * If we're out of space, disable receive interrupts * until the queue has drained a bit. */ if (!cc) { SET(sc->sc_rx_flags, RX_IBUF_OVERFLOWED); CLR(sc->sc_ier, IER_ERXRDY); bus_space_write_1(iot, ioh, com_ier, sc->sc_ier); } } else { if ((iir & IIR_IMASK) == IIR_RXRDY) { bus_space_write_1(iot, ioh, com_ier, 0); delay(10); bus_space_write_1(iot, ioh, com_ier,sc->sc_ier); iir = IIR_NOPEND; continue; } } msr = bus_space_read_1(iot, ioh, com_msr); delta = msr ^ sc->sc_msr; sc->sc_msr = msr; if (ISSET(delta, sc->sc_msr_mask)) { sc->sc_msr_delta |= delta; /* * Stop output immediately if we lose the output * flow control signal or carrier detect. */ if (ISSET(~msr, sc->sc_msr_mask)) { sc->sc_tbc = 0; sc->sc_heldtbc = 0; #ifdef COM_DEBUG if (com_debug) comstatus(sc, "comintr "); #endif } sc->sc_st_check = 1; } } while (!ISSET((iir = bus_space_read_1(iot, ioh, com_iir)), IIR_NOPEND)); /* * Done handling any receive interrupts. See if data can be * transmitted as well. Schedule tx done event if no data left * and tty was marked busy. */ if (ISSET(lsr, LSR_TXRDY)) { /* * If we've delayed a parameter change, do it now, and restart * output. */ if (sc->sc_heldchange) { com_loadchannelregs(sc); sc->sc_heldchange = 0; sc->sc_tbc = sc->sc_heldtbc; sc->sc_heldtbc = 0; } /* Output the next chunk of the contiguous buffer, if any. */ if (sc->sc_tbc > 0) { int n; n = sc->sc_fifolen; if (n > sc->sc_tbc) n = sc->sc_tbc; bus_space_write_multi_1(iot, ioh, com_data, sc->sc_tba, n); sc->sc_tbc -= n; sc->sc_tba += n; } else if (sc->sc_tx_busy) { sc->sc_tx_busy = 0; sc->sc_tx_done = 1; } } /* Wake up the poller. */ #ifdef __GENERIC_SOFT_INTERRUPTS softintr_schedule(sc->sc_si); #else #ifndef alpha setsoftserial(); #else if (!com_softintr_scheduled) { com_softintr_scheduled = 1; timeout(comsoft, NULL, 1); } #endif #endif return (1); } /* * The following functions are polled getc and putc routines, shared * by the console and kgdb glue. */ int com_common_getc(iot, ioh) bus_space_tag_t iot; bus_space_handle_t ioh; { int s = splserial(); u_char stat, c; while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_RXRDY)) ; c = bus_space_read_1(iot, ioh, com_data); stat = bus_space_read_1(iot, ioh, com_iir); splx(s); return (c); } void com_common_putc(iot, ioh, c) bus_space_tag_t iot; bus_space_handle_t ioh; int c; { int s = splserial(); u_char stat; register int timo; /* wait for any pending transmission to finish */ timo = 50000; while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo) ; bus_space_write_1(iot, ioh, com_data, c); /* wait for this transmission to complete */ timo = 1500000; while (!ISSET(stat = bus_space_read_1(iot, ioh, com_lsr), LSR_TXRDY) && --timo) ; /* clear any interrupts generated by this transmission */ stat = bus_space_read_1(iot, ioh, com_iir); splx(s); } /* * Initialize UART to known state. */ int cominit(iot, iobase, rate, cflag, iohp) bus_space_tag_t iot; int iobase; int rate; tcflag_t cflag; bus_space_handle_t *iohp; { bus_space_handle_t ioh; if (bus_space_map(iot, iobase, COM_NPORTS, 0, &ioh)) return(ENOMEM); /* ??? */ bus_space_write_1(iot, ioh, com_lcr, LCR_DLAB); rate = comspeed(rate); bus_space_write_1(iot, ioh, com_dlbl, rate); bus_space_write_1(iot, ioh, com_dlbh, rate >> 8); bus_space_write_1(iot, ioh, com_lcr, cflag2lcr(cflag)); bus_space_write_1(iot, ioh, com_mcr, 0); bus_space_write_1(iot, ioh, com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST | FIFO_TRIGGER_1); bus_space_write_1(iot, ioh, com_ier, 0); *iohp = ioh; return(0); } /* * Following are all routines needed for COM to act as console */ int comcnattach(iot, iobase, rate, cflag) bus_space_tag_t iot; int iobase; int rate; tcflag_t cflag; { int res; static struct consdev comcons = { NULL, NULL, comcngetc, comcnputc, comcnpollc, NODEV, CN_NORMAL}; res = cominit(iot, iobase, rate, cflag, &comconsioh); if(res) return(res); cn_tab = &comcons; comconstag = iot; comconsaddr = iobase; comconsrate = rate; comconscflag = cflag; return(0); } int comcngetc(dev) dev_t dev; { return (com_common_getc(comconstag, comconsioh)); } /* * Console kernel output character routine. */ void comcnputc(dev, c) dev_t dev; int c; { com_common_putc(comconstag, comconsioh, c); } void comcnpollc(dev, on) dev_t dev; int on; { } #ifdef KGDB int com_kgdb_attach(iot, iobase, rate, cflag) bus_space_tag_t iot; int iobase; int rate; tcflag_t cflag; { int res; if (iot == comconstag && iobase == comconsaddr) return(EBUSY); /* cannot share with console */ res = cominit(iot, iobase, rate, cflag, &com_kgdb_ioh); if(res) return(res); kgdb_attach(com_kgdb_getc, com_kgdb_putc, NULL); kgdb_dev = 123; /* unneeded, only to satisfy some tests */ com_kgdb_iot = iot; com_kgdb_addr = iobase; return(0); } /* ARGSUSED */ int com_kgdb_getc(arg) void *arg; { return (com_common_getc(com_kgdb_iot, com_kgdb_ioh)); } /* ARGSUSED */ void com_kgdb_putc(arg, c) void *arg; int c; { return (com_common_putc(com_kgdb_iot, com_kgdb_ioh, c)); } #endif /* KGDB */ /* helper function to identify the com ports used by console or KGDB (and not yet autoconf attached) */ int com_is_console(iot, iobase, ioh) bus_space_tag_t iot; int iobase; bus_space_handle_t *ioh; { bus_space_handle_t help; if (!comconsattached && iot == comconstag && iobase == comconsaddr) help = comconsioh; #ifdef KGDB else if (!com_kgdb_attached && iot == com_kgdb_iot && iobase == com_kgdb_addr) help = com_kgdb_ioh; #endif else return(0); if(ioh) *ioh = help; return(1); }