/*- * Copyright (c) 1992, 1993, 1995 Eugene W. Stark * 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 Eugene W. Stark. * 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 EUGENE W. STARK (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. */ #include "tw.h" #if NTW > 0 /* * Driver configuration parameters */ /* * Time for 1/2 of a power line cycle, in microseconds. * Change this to 10000 for 50Hz power. Phil Sampson * (vk2jnt@gw.vk2jnt.ampr.org OR sampson@gidday.enet.dec.com) * reports that this works (at least in Australia) using a * TW7223 module (a local version of the TW523). */ #define HALFCYCLE 8333 /* 1/2 cycle = 8333us at 60Hz */ /* * Undefine the following if you don't have the high-resolution "microtime" * routines (leave defined for FreeBSD, which has them). */ #define HIRESTIME /* * End of driver configuration parameters */ /* * FreeBSD Device Driver for X-10 POWERHOUSE (tm) * Two-Way Power Line Interface, Model #TW523 * * written by Eugene W. Stark (stark@cs.sunysb.edu) * December 2, 1992 * * NOTES: * * The TW523 is a carrier-current modem for home control/automation purposes. * It is made by: * * X-10 Inc. * 185A LeGrand Ave. * Northvale, NJ 07647 * USA * (201) 784-9700 or 1-800-526-0027 * * X-10 Home Controls Inc. * 1200 Aerowood Drive, Unit 20 * Mississauga, Ontario * (416) 624-4446 or 1-800-387-3346 * * The TW523 is designed for communications using the X-10 protocol, * which is compatible with a number of home control systems, including * Radio Shack "Plug 'n Power(tm)" and Stanley "Lightmaker(tm)." * I bought my TW523 from: * * Home Control Concepts * 9353-C Activity Road * San Diego, CA 92126 * (619) 693-8887 * * They supplied me with the TW523 (which has an RJ-11 four-wire modular * telephone connector), a modular cable, an RJ-11 to DB-25 connector with * internal wiring, documentation from X-10 on the TW523 (very good), * an instruction manual by Home Control Concepts (not very informative), * and a floppy disk containing binary object code of some demonstration/test * programs and of a C function library suitable for controlling the TW523 * by an IBM PC under MS-DOS (not useful to me other than to verify that * the unit worked). I suggest saving money and buying the bare TW523 * rather than the TW523 development kit (what I bought), because if you * are running FreeBSD you don't really care about the DOS binaries. * * The interface to the TW-523 consists of four wires on the RJ-11 connector, * which are jumpered to somewhat more wires on the DB-25 connector, which * in turn is intended to plug into the PC parallel printer port. I dismantled * the DB-25 connector to find out what they had done: * * Signal RJ-11 pin DB-25 pin(s) Parallel Port * Transmit TX 4 (Y) 2, 4, 6, 8 Data out * Receive RX 3 (G) 10, 14 -ACK, -AutoFeed * Common 2 (R) 25 Common * Zero crossing 1 (B) 17 -Select Input * * The zero crossing signal is used to synchronize transmission to the * zero crossings of the AC line, as detailed in the X-10 documentation. * It would be nice if one could generate interrupts with this signal, * however one needs interrupts on both the rising and falling edges, * and the -ACK signal to the parallel port interrupts only on the falling * edge, so it can't be done without additional hardware. * * In this driver, the transmit function is performed in a non-interrupt-driven * fashion, by polling the zero crossing signal to determine when a transition * has occurred. This wastes CPU time during transmission, but it seems like * the best that can be done without additional hardware. One problem with * the scheme is that preemption of the CPU during transmission can cause loss * of sync. The driver tries to catch this, by noticing that a long delay * loop has somehow become foreshortened, and the transmission is aborted with * an error return. It is up to the user level software to handle this * situation (most likely by retrying the transmission). */ #include #include #include #include #include #include #include #include #include #ifdef DEVFS #include #endif /*DEVFS*/ #define MIN(a,b) ((a)<(b)?(a):(b)) #ifdef HIRESTIME #include #endif /* HIRESTIME */ #include /* * Transmission is done by calling write() to send three byte packets of data. * The first byte contains a four bit house code (0=A to 15=P). * The second byte contains five bit unit/key code (0=unit 1 to 15=unit 16, * 16=All Units Off to 31 = Status Request). The third byte specifies * the number of times the packet is to be transmitted without any * gaps between successive transmissions. Normally this is 2, as per * the X-10 documentation, but sometimes (e.g. for bright and dim codes) * it can be another value. Each call to write can specify an arbitrary * number of data bytes. An incomplete packet is buffered until a subsequent * call to write() provides data to complete it. At most one packet will * actually be processed in any call to write(). Successive calls to write() * leave a three-cycle gap between transmissions, per the X-10 documentation. * * Reception is done using read(). * The driver produces a series of three-character packets. * In each packet, the first character consists of flags, * the second character is a four bit house code (0-15), * and the third character is a five bit key/function code (0-31). * The flags are the following: */ #define TW_RCV_LOCAL 1 /* The packet arrived during a local transmission */ #define TW_RCV_ERROR 2 /* An invalid/corrupted packet was received */ /* * IBM PC parallel port definitions relevant to TW523 */ #define tw_data 0 /* Data to tw523 (R/W) */ #define tw_status 1 /* Status of tw523 (R) */ #define TWS_RDATA 0x40 /* tw523 receive data */ #define tw_control 2 /* Control tw523 (R/W) */ #define TWC_SYNC 0x08 /* tw523 sync (pin 17) */ #define TWC_ENA 0x10 /* tw523 interrupt enable */ /* * Miscellaneous defines */ #define TWUNIT(dev) (minor(dev)) /* Extract unit number from device */ #define TWPRI (PZERO+8) /* I don't know any better, so let's */ /* use the same as the line printer */ static int twprobe(struct isa_device *idp); static int twattach(struct isa_device *idp); struct isa_driver twdriver = { twprobe, twattach, "tw" }; static d_open_t twopen; static d_close_t twclose; static d_read_t twread; static d_write_t twwrite; static d_select_t twselect; #define CDEV_MAJOR 19 static struct cdevsw tw_cdevsw = { twopen, twclose, twread, twwrite, /*19*/ noioc, nullstop, nullreset, nodevtotty, /* tw */ twselect, nommap, nostrat, "tw", NULL, -1 }; /* * Software control structure for TW523 */ #define TWS_XMITTING 1 /* Transmission in progress */ #define TWS_RCVING 2 /* Reception in progress */ #define TWS_WANT 4 /* A process wants received data */ #define TWS_OPEN 8 /* Is it currently open? */ #define TW_SIZE 3*60 /* Enough for about 10 sec. of input */ static struct tw_sc { u_int sc_port; /* I/O Port */ u_int sc_state; /* Current software control state */ struct selinfo sc_selp; /* Information for select() */ u_char sc_xphase; /* Current state of sync (for transmitter) */ u_char sc_rphase; /* Current state of sync (for receiver) */ u_char sc_flags; /* Flags for current reception */ short sc_rcount; /* Number of bits received so far */ int sc_bits; /* Bits received so far */ u_char sc_pkt[3]; /* Packet not yet transmitted */ short sc_pktsize; /* How many bytes in the packet? */ u_char sc_buf[TW_SIZE]; /* We buffer our own input */ int sc_nextin; /* Next free slot in circular buffer */ int sc_nextout; /* First used slot in circular buffer */ #ifdef HIRESTIME int sc_xtimes[22]; /* Times for bits in current xmit packet */ int sc_rtimes[22]; /* Times for bits in current rcv packet */ #endif /* HIRESTIME */ #ifdef DEVFS void *devfs_token; /* store the devfs handle */ #endif } tw_sc[NTW]; static void twdelay25(void); static void twdelayn(int n); static void twsetuptimes(int *a); static int wait_for_zero(struct tw_sc *sc); static int twgetbytes(struct tw_sc *sc, u_char *p, int cnt); static void twabortrcv(struct tw_sc *sc); static int twsend(struct tw_sc *sc, int h, int k, int cnt); static int next_zero(struct tw_sc *sc); static int twputpkt(struct tw_sc *sc, u_char *p); static int twchecktime(int target, int tol); /* * Counter value for delay loop. * It is adjusted by twprobe so that the delay loop takes about 25us. */ #define TWDELAYCOUNT 161 /* Works on my 486DX/33 */ static int twdelaycount; /* * Twdelay25 is used for very short delays of about 25us. * It is implemented with a calibrated delay loop, and should be * fairly accurate ... unless we are preempted by an interrupt. * * We use this to wait for zero crossings because the X-10 specs say we * are supposed to assert carrier within 25us when one happens. * I don't really believe we can do this, but the X-10 devices seem to be * fairly forgiving. */ static void twdelay25() { int cnt; for(cnt = twdelaycount; cnt; cnt--); /* Should take about 25us */ } /* * Twdelayn is used to time the length of the 1ms carrier pulse. * This is not very critical, but if we have high-resolution time-of-day * we check it every apparent 200us to make sure we don't get too far off * if we happen to be interrupted during the delay. */ static void twdelayn(int n) { #ifdef HIRESTIME int t, d; struct timeval tv; microtime(&tv); t = tv.tv_usec; t += n; #endif /* HIRESTIME */ while(n > 0) { twdelay25(); n -= 25; #ifdef HIRESTIME if((n & 0x7) == 0) { microtime(&tv); d = tv.tv_usec - t; if(d >= 0 && d < 1000000) return; } #endif /* HIRESTIME */ } } static int twprobe(idp) struct isa_device *idp; { struct tw_sc sc; int d; int tries; sc.sc_port = idp->id_iobase; /* * Iteratively check the timing of a few sync transitions, and adjust * the loop delay counter, if necessary, to bring the timing reported * by wait_for_zero() close to HALFCYCLE. Give up if anything * ridiculous happens. */ if(twdelaycount == 0) { /* Only adjust timing for first unit */ twdelaycount = TWDELAYCOUNT; for(tries = 0; tries < 10; tries++) { sc.sc_xphase = inb(idp->id_iobase + tw_control) & TWC_SYNC; if(wait_for_zero(&sc) >= 0) { d = wait_for_zero(&sc); if(d <= HALFCYCLE/100 || d >= HALFCYCLE*100) { twdelaycount = 0; return(0); } twdelaycount = (twdelaycount * d)/HALFCYCLE; } } } /* * Now do a final check, just to make sure */ sc.sc_xphase = inb(idp->id_iobase + tw_control) & TWC_SYNC; if(wait_for_zero(&sc) >= 0) { d = wait_for_zero(&sc); if(d <= (HALFCYCLE * 110)/100 && d >= (HALFCYCLE * 90)/100) return(1); } return(0); } static int twattach(idp) struct isa_device *idp; { struct tw_sc *sc; int unit; sc = &tw_sc[unit = idp->id_unit]; sc->sc_port = idp->id_iobase; sc->sc_state = 0; #ifdef DEVFS sc->devfs_token = devfs_add_devswf(&tw_cdevsw, unit, DV_CHR, 0, 0, 0600, "tw%d", unit); #endif return (1); } int twopen(dev, flag, mode, p) dev_t dev; int flag; int mode; struct proc *p; { struct tw_sc *sc = &tw_sc[TWUNIT(dev)]; int s; s = spltty(); if(sc->sc_state == 0) { sc->sc_state = TWS_OPEN; sc->sc_nextin = sc->sc_nextout = 0; sc->sc_pktsize = 0; outb(sc->sc_port+tw_control, TWC_ENA); } splx(s); return(0); } int twclose(dev, flag, mode, p) dev_t dev; int flag; int mode; struct proc *p; { struct tw_sc *sc = &tw_sc[TWUNIT(dev)]; int s; s = spltty(); sc->sc_state = 0; outb(sc->sc_port+tw_control, 0); splx(s); return(0); } int twread(dev, uio, ioflag) dev_t dev; struct uio *uio; int ioflag; { u_char buf[3]; struct tw_sc *sc = &tw_sc[TWUNIT(dev)]; int error, cnt, s; s = spltty(); cnt = MIN(uio->uio_resid, 3); if((error = twgetbytes(sc, buf, cnt)) == 0) { error = uiomove(buf, cnt, uio); } splx(s); return(error); } int twwrite(dev, uio, ioflag) dev_t dev; struct uio *uio; int ioflag; { struct tw_sc *sc; int house, key, reps; int s, error; int cnt; sc = &tw_sc[TWUNIT(dev)]; /* * Note: Although I had intended to allow concurrent transmitters, * there is a potential problem here if two processes both write * into the sc_pkt buffer at the same time. The following code * is an additional critical section that needs to be synchronized. */ s = spltty(); cnt = MIN(3 - sc->sc_pktsize, uio->uio_resid); if(error = uiomove(&(sc->sc_pkt[sc->sc_pktsize]), cnt, uio)) { splx(s); return(error); } sc->sc_pktsize += cnt; if(sc->sc_pktsize < 3) { /* Only transmit 3-byte packets */ splx(s); return(0); } sc->sc_pktsize = 0; /* * Collect house code, key code, and rep count, and check for sanity. */ house = sc->sc_pkt[0]; key = sc->sc_pkt[1]; reps = sc->sc_pkt[2]; if(house >= 16 || key >= 32) { splx(s); return(ENODEV); } /* * Synchronize with the receiver operating in the bottom half, and * also with concurrent transmitters. * We don't want to interfere with a packet currently being received, * and we would like the receiver to recognize when a packet has * originated locally. */ while(sc->sc_state & (TWS_RCVING | TWS_XMITTING)) { if(error = tsleep((caddr_t)sc, TWPRI|PCATCH, "twwrite", 0)) { splx(s); return(error); } } sc->sc_state |= TWS_XMITTING; /* * Everything looks OK, let's do the transmission. */ splx(s); /* Enable interrupts because this takes a LONG time */ error = twsend(sc, house, key, reps); s = spltty(); sc->sc_state &= ~TWS_XMITTING; wakeup((caddr_t)sc); splx(s); if(error) return(EIO); else return(0); } /* * Determine if there is data available for reading */ int twselect(dev, rw, p) dev_t dev; int rw; struct proc *p; { struct tw_sc *sc; int s; sc = &tw_sc[TWUNIT(dev)]; s = spltty(); if(sc->sc_nextin != sc->sc_nextout) { splx(s); return(1); } selrecord(p, &sc->sc_selp); splx(s); return(0); } /* * X-10 Protocol */ #define X10_START_LENGTH 4 static char X10_START[] = { 1, 1, 1, 0 }; /* * Each bit of the 4-bit house code and 5-bit key code * is transmitted twice, once in true form, and then in * complemented form. This is already taken into account * in the following tables. */ #define X10_HOUSE_LENGTH 8 static char X10_HOUSE[16][8] = { 0, 1, 1, 0, 1, 0, 0, 1, /* A = 0110 */ 1, 0, 1, 0, 1, 0, 0, 1, /* B = 1110 */ 0, 1, 0, 1, 1, 0, 0, 1, /* C = 0010 */ 1, 0, 0, 1, 1, 0, 0, 1, /* D = 1010 */ 0, 1, 0, 1, 0, 1, 1, 0, /* E = 0001 */ 1, 0, 0, 1, 0, 1, 1, 0, /* F = 1001 */ 0, 1, 1, 0, 0, 1, 1, 0, /* G = 0101 */ 1, 0, 1, 0, 0, 1, 1, 0, /* H = 1101 */ 0, 1, 1, 0, 1, 0, 1, 0, /* I = 0111 */ 1, 0, 1, 0, 1, 0, 1, 0, /* J = 1111 */ 0, 1, 0, 1, 1, 0, 1, 0, /* K = 0011 */ 1, 0, 0, 1, 1, 0, 1, 0, /* L = 1011 */ 0, 1, 0, 1, 0, 1, 0, 1, /* M = 0000 */ 1, 0, 0, 1, 0, 1, 0, 1, /* N = 1000 */ 0, 1, 1, 0, 0, 1, 0, 1, /* O = 0100 */ 1, 0, 1, 0, 0, 1, 0, 1 /* P = 1100 */ }; #define X10_KEY_LENGTH 10 static char X10_KEY[32][10] = { 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, /* 01100 => 1 */ 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, /* 11100 => 2 */ 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, /* 00100 => 3 */ 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, /* 10100 => 4 */ 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, /* 00010 => 5 */ 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, /* 10010 => 6 */ 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, /* 01010 => 7 */ 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, /* 11010 => 8 */ 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, /* 01110 => 9 */ 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, /* 11110 => 10 */ 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, /* 00110 => 11 */ 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, /* 10110 => 12 */ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, /* 00000 => 13 */ 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, /* 10000 => 14 */ 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, /* 01000 => 15 */ 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, /* 11000 => 16 */ 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, /* 00001 => All Units Off */ 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, /* 00011 => All Units On */ 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, /* 00101 => On */ 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, /* 00111 => Off */ 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, /* 01001 => Dim */ 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, /* 01011 => Bright */ 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, /* 01101 => All LIGHTS Off */ 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, /* 01111 => Extended Code */ 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, /* 10001 => Hail Request */ 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, /* 10011 => Hail Acknowledge */ 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, /* 10101 => Preset Dim 0 */ 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, /* 10111 => Preset Dim 1 */ 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, /* 11000 => Extended Data (analog) */ 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, /* 11011 => Status = on */ 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, /* 11101 => Status = off */ 1, 0, 1, 0, 1, 0, 1, 0, 1, 0 /* 11111 => Status request */ }; /* * Tables for mapping received X-10 code back to house/key number. */ static short X10_HOUSE_INV[16] = { 12, 4, 2, 10, 14, 6, 0, 8, 13, 5, 3, 11, 15, 7, 1, 9 }; static short X10_KEY_INV[32] = { 12, 16, 4, 17, 2, 18, 10, 19, 14, 20, 6, 21, 0, 22, 8, 23, 13, 24, 5, 25, 3, 26, 11, 27, 15, 28, 7, 29, 1, 30, 9, 31 }; /* * Transmit a packet containing house code h and key code k */ #define TWRETRY 10 /* Try 10 times to sync with AC line */ static int twsend(sc, h, k, cnt) struct tw_sc *sc; int h, k, cnt; { int i; int port = sc->sc_port; /* * Make sure we get a reliable sync with a power line zero crossing */ for(i = 0; i < TWRETRY; i++) { if(wait_for_zero(sc) > 100) goto insync; } log(LOG_ERR, "TWXMIT: failed to sync.\n"); return(-1); insync: /* * Be sure to leave 3 cycles space between transmissions */ for(i = 6; i > 0; i--) if(next_zero(sc) < 0) return(-1); /* * The packet is transmitted cnt times, with no gaps. */ while(cnt--) { /* * Transmit the start code */ for(i = 0; i < X10_START_LENGTH; i++) { outb(port+tw_data, X10_START[i] ? 0xff : 0x00); /* Waste no time! */ #ifdef HIRESTIME if(i == 0) twsetuptimes(sc->sc_xtimes); if(twchecktime(sc->sc_xtimes[i], HALFCYCLE/20) == 0) { outb(port+tw_data, 0); return(-1); } #endif /* HIRESTIME */ twdelayn(1000); /* 1ms pulse width */ outb(port+tw_data, 0); if(next_zero(sc) < 0) return(-1); } /* * Transmit the house code */ for(i = 0; i < X10_HOUSE_LENGTH; i++) { outb(port+tw_data, X10_HOUSE[h][i] ? 0xff : 0x00); /* Waste no time! */ #ifdef HIRESTIME if(twchecktime(sc->sc_xtimes[i+X10_START_LENGTH], HALFCYCLE/20) == 0) { outb(port+tw_data, 0); return(-1); } #endif /* HIRESTIME */ twdelayn(1000); /* 1ms pulse width */ outb(port+tw_data, 0); if(next_zero(sc) < 0) return(-1); } /* * Transmit the unit/key code */ for(i = 0; i < X10_KEY_LENGTH; i++) { outb(port+tw_data, X10_KEY[k][i] ? 0xff : 0x00); #ifdef HIRESTIME if(twchecktime(sc->sc_xtimes[i+X10_START_LENGTH+X10_HOUSE_LENGTH], HALFCYCLE/20) == 0) { outb(port+tw_data, 0); return(-1); } #endif /* HIRESTIME */ twdelayn(1000); /* 1ms pulse width */ outb(port+tw_data, 0); if(next_zero(sc) < 0) return(-1); } } return(0); } /* * Waste CPU cycles to get in sync with a power line zero crossing. * The value returned is roughly how many microseconds we wasted before * seeing the transition. To avoid wasting time forever, we give up after * waiting patiently for 1/4 sec (15 power line cycles at 60 Hz), * which is more than the 11 cycles it takes to transmit a full * X-10 packet. */ static int wait_for_zero(sc) struct tw_sc *sc; { int i, old, new, max; int port = sc->sc_port + tw_control; old = sc->sc_xphase; max = 10000; /* 10000 * 25us = 0.25 sec */ i = 0; while(max--) { new = inb(port) & TWC_SYNC; if(new != old) { sc->sc_xphase = new; return(i*25); } i++; twdelay25(); } return(-1); } /* * Wait for the next zero crossing transition, and if we don't have * high-resolution time-of-day, check to see that the zero crossing * appears to be arriving on schedule. * We expect to be waiting almost a full half-cycle (8.333ms-1ms = 7.333ms). * If we don't seem to wait very long, something is wrong (like we got * preempted!) and we should abort the transmission because * there's no telling how long it's really been since the * last bit was transmitted. */ static int next_zero(sc) struct tw_sc *sc; { int d; #ifdef HIRESTIME if((d = wait_for_zero(sc)) < 0) { #else if((d = wait_for_zero(sc)) < 6000 || d > 8500) { /* No less than 6.0ms, no more than 8.5ms */ #endif /* HIRESTIME */ log(LOG_ERR, "TWXMIT framing error: %d\n", d); return(-1); } return(0); } /* * Put a three-byte packet into the circular buffer * Should be called at priority spltty() */ static int twputpkt(sc, p) struct tw_sc *sc; u_char *p; { int i, next; for(i = 0; i < 3; i++) { next = sc->sc_nextin+1; if(next >= TW_SIZE) next = 0; if(next == sc->sc_nextout) { /* Buffer full */ /* log(LOG_ERR, "TWRCV: Buffer overrun\n"); */ return(1); } sc->sc_buf[sc->sc_nextin] = *p++; sc->sc_nextin = next; } if(sc->sc_state & TWS_WANT) { sc->sc_state &= ~TWS_WANT; wakeup((caddr_t)(&sc->sc_buf)); } selwakeup(&sc->sc_selp); return(0); } /* * Get bytes from the circular buffer * Should be called at priority spltty() */ static int twgetbytes(sc, p, cnt) struct tw_sc *sc; u_char *p; int cnt; { int error; while(cnt--) { while(sc->sc_nextin == sc->sc_nextout) { /* Buffer empty */ sc->sc_state |= TWS_WANT; if(error = tsleep((caddr_t)(&sc->sc_buf), TWPRI|PCATCH, "twread", 0)) { return(error); } } *p++ = sc->sc_buf[sc->sc_nextout++]; if(sc->sc_nextout >= TW_SIZE) sc->sc_nextout = 0; } return(0); } /* * Abort reception that has failed to complete in the required time. */ static void twabortrcv(sc) struct tw_sc *sc; { int s; u_char pkt[3]; s = spltty(); sc->sc_state &= ~TWS_RCVING; sc->sc_flags |= TW_RCV_ERROR; pkt[0] = sc->sc_flags; pkt[1] = pkt[2] = 0; twputpkt(sc, pkt); log(LOG_ERR, "TWRCV: aborting (%x, %d)\n", sc->sc_bits, sc->sc_rcount); wakeup((caddr_t)sc); splx(s); } /* * This routine handles interrupts that occur when there is a falling * transition on the RX input. There isn't going to be a transition * on every bit (some are zero), but if we are smart and keep track of * how long it's been since the last interrupt (via the zero crossing * detect line and/or high-resolution time-of-day routine), we can * reconstruct the transmission without having to poll. */ void twintr(unit) int unit; { struct tw_sc *sc = &tw_sc[unit]; int port; int newphase; u_char pkt[3]; port = sc->sc_port; /* * Ignore any interrupts that occur if the device is not open. */ if(sc->sc_state == 0) return; newphase = inb(port + tw_control) & TWC_SYNC; /* * NEW PACKET: * If we aren't currently receiving a packet, set up a new packet * and put in the first "1" bit that has just arrived. * Arrange for the reception to be aborted if too much time goes by. */ if((sc->sc_state & TWS_RCVING) == 0) { #ifdef HIRESTIME twsetuptimes(sc->sc_rtimes); #endif /* HIRESTIME */ sc->sc_state |= TWS_RCVING; sc->sc_rcount = 1; if(sc->sc_state & TWS_XMITTING) sc->sc_flags = TW_RCV_LOCAL; else sc->sc_flags = 0; sc->sc_bits = 0; sc->sc_rphase = newphase; timeout((timeout_func_t)twabortrcv, (caddr_t)sc, hz/4); return; } /* * START CODE: * The second and third bits are a special case. */ if(sc->sc_rcount < 3) { #ifdef HIRESTIME if(twchecktime(sc->sc_rtimes[sc->sc_rcount], HALFCYCLE/3) && newphase != sc->sc_rphase) { #else if(newphase != sc->sc_rphase) { #endif sc->sc_rcount++; } else { /* * Invalid start code -- abort reception. */ sc->sc_state &= ~TWS_RCVING; sc->sc_flags |= TW_RCV_ERROR; /* pkt[0] = sc->sc_flags; pkt[1] = pkt[2] = 0; twputpkt(sc, pkt); wakeup((caddr_t)sc); */ untimeout((timeout_func_t)twabortrcv, (caddr_t)sc); log(LOG_ERR, "TWRCV: Invalid start code\n"); return; } if(sc->sc_rcount == 3) { /* * We've gotten three "1" bits in a row. The start code * is really 1110, but this might be followed by a zero * bit from the house code, so if we wait any longer we * might be confused about the first house code bit. * So, we guess that the start code is correct and insert * the trailing zero without actually having seen it. * We don't change sc_rphase in this case, because two * bit arrivals in a row preserve parity. */ sc->sc_rcount++; return; } /* * Update sc_rphase to the current phase before returning. */ sc->sc_rphase = newphase; return; } /* * GENERAL CASE: * Now figure out what the current bit is that just arrived. * The X-10 protocol transmits each data bit twice: once in * true form and once in complemented form on the next half * cycle. So, there will be at least one interrupt per bit. * By comparing the phase we see at the time of the interrupt * with the saved sc_rphase, we can tell on which half cycle * the interrupt occrred. This assumes, of course, that the * packet is well-formed. We do the best we can at trying to * catch errors by aborting if too much time has gone by, and * by tossing out a packet if too many bits arrive, but the * whole scheme is probably not as robust as if we had a nice * interrupt on every half cycle of the power line. * If we have high-resolution time-of-day routines, then we * can do a bit more sanity checking. */ /* * A complete packet is 22 half cycles. */ if(sc->sc_rcount <= 20) { #ifdef HIRESTIME if((newphase == sc->sc_rphase && twchecktime(sc->sc_rtimes[sc->sc_rcount+1], HALFCYCLE/3) == 0) || (newphase != sc->sc_rphase && twchecktime(sc->sc_rtimes[sc->sc_rcount], HALFCYCLE/3) == 0)) { sc->sc_flags |= TW_RCV_ERROR; } else { #endif /* HIRESTIME */ sc->sc_bits = (sc->sc_bits << 1) | ((newphase == sc->sc_rphase) ? 0x0 : 0x1); sc->sc_rcount += 2; #ifdef HIRESTIME } #endif /* HIRESTIME */ } if(sc->sc_rcount >= 22 || sc->sc_flags & TW_RCV_ERROR) { if(sc->sc_rcount != 22) { sc->sc_flags |= TW_RCV_ERROR; pkt[0] = sc->sc_flags; pkt[1] = pkt[2] = 0; } else { pkt[0] = sc->sc_flags; pkt[1] = X10_HOUSE_INV[(sc->sc_bits & 0x1e0) >> 5]; pkt[2] = X10_KEY_INV[sc->sc_bits & 0x1f]; } sc->sc_state &= ~TWS_RCVING; twputpkt(sc, pkt); untimeout((timeout_func_t)twabortrcv, (caddr_t)sc); if(sc->sc_flags & TW_RCV_ERROR) log(LOG_ERR, "TWRCV: invalid packet: (%d, %x)\n", sc->sc_rcount, sc->sc_bits); wakeup((caddr_t)sc); } } #ifdef HIRESTIME /* * Initialize an array of 22 times, starting from the current * microtime and continuing for the next 21 half cycles. * We use the times as a reference to make sure transmission * or reception is on schedule. */ static void twsetuptimes(int *a) { struct timeval tv; int i, t; microtime(&tv); t = tv.tv_usec; for(i = 0; i < 22; i++) { *a++ = t; t += HALFCYCLE; if(t >= 1000000) t -= 1000000; } } /* * Check the current time against a slot in a previously set up * timing array, and make sure that it looks like we are still * on schedule. */ static int twchecktime(int target, int tol) { struct timeval tv; int t, d; microtime(&tv); t = tv.tv_usec; d = (target - t) >= 0 ? (target - t) : (t - target); if(d > 500000) d = 1000000-d; if(d <= tol && d >= -tol) { return(1); } else { log(LOG_ERR, "TWCHK: timing off by %dus (>= %dus)\n", d, tol); return(0); } } #endif /* HIRESTIME */ static tw_devsw_installed = 0; static void tw_drvinit(void *unused) { dev_t dev; if( ! tw_devsw_installed ) { dev = makedev(CDEV_MAJOR, 0); cdevsw_add(&dev,&tw_cdevsw, NULL); tw_devsw_installed = 1; } } SYSINIT(twdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,tw_drvinit,NULL) #endif NTW