2 * Copyright (c) 1992, 1993, 1995 Eugene W. Stark
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Eugene W. Stark.
16 * 4. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY EUGENE W. STARK (THE AUTHOR) ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * $FreeBSD: src/sys/i386/isa/tw.c,v 1.38 2000/01/29 16:00:32 peter Exp $
32 * $DragonFly: src/sys/dev/misc/tw/tw.c,v 1.8 2003/08/07 21:16:59 dillon Exp $
39 * Driver configuration parameters
43 * Time for 1/2 of a power line cycle, in microseconds.
44 * Change this to 10000 for 50Hz power. Phil Sampson
45 * (vk2jnt@gw.vk2jnt.ampr.org OR sampson@gidday.enet.dec.com)
46 * reports that this works (at least in Australia) using a
47 * TW7223 module (a local version of the TW523).
49 #define HALFCYCLE 8333 /* 1/2 cycle = 8333us at 60Hz */
52 * Undefine the following if you don't have the high-resolution "microtime"
53 * routines (leave defined for FreeBSD, which has them).
58 * End of driver configuration parameters
62 * FreeBSD Device Driver for X-10 POWERHOUSE (tm)
63 * Two-Way Power Line Interface, Model #TW523
65 * written by Eugene W. Stark (stark@cs.sunysb.edu)
70 * The TW523 is a carrier-current modem for home control/automation purposes.
77 * (201) 784-9700 or 1-800-526-0027
79 * X-10 Home Controls Inc.
80 * 1200 Aerowood Drive, Unit 20
81 * Mississauga, Ontario
82 * (416) 624-4446 or 1-800-387-3346
84 * The TW523 is designed for communications using the X-10 protocol,
85 * which is compatible with a number of home control systems, including
86 * Radio Shack "Plug 'n Power(tm)" and Stanley "Lightmaker(tm)."
87 * I bought my TW523 from:
89 * Home Control Concepts
90 * 9353-C Activity Road
94 * They supplied me with the TW523 (which has an RJ-11 four-wire modular
95 * telephone connector), a modular cable, an RJ-11 to DB-25 connector with
96 * internal wiring, documentation from X-10 on the TW523 (very good),
97 * an instruction manual by Home Control Concepts (not very informative),
98 * and a floppy disk containing binary object code of some demonstration/test
99 * programs and of a C function library suitable for controlling the TW523
100 * by an IBM PC under MS-DOS (not useful to me other than to verify that
101 * the unit worked). I suggest saving money and buying the bare TW523
102 * rather than the TW523 development kit (what I bought), because if you
103 * are running FreeBSD you don't really care about the DOS binaries.
105 * The interface to the TW-523 consists of four wires on the RJ-11 connector,
106 * which are jumpered to somewhat more wires on the DB-25 connector, which
107 * in turn is intended to plug into the PC parallel printer port. I dismantled
108 * the DB-25 connector to find out what they had done:
110 * Signal RJ-11 pin DB-25 pin(s) Parallel Port
111 * Transmit TX 4 (Y) 2, 4, 6, 8 Data out
112 * Receive RX 3 (G) 10, 14 -ACK, -AutoFeed
113 * Common 2 (R) 25 Common
114 * Zero crossing 1 (B) 17 or 12 -Select or +PaperEnd
116 * NOTE: In the original cable I have (which I am still using, May, 1997)
117 * the Zero crossing signal goes to pin 17 (-Select) on the parallel port.
118 * In retrospect, this doesn't make a whole lot of sense, given that the
119 * -Select signal propagates the other direction. Indeed, some people have
120 * reported problems with this, and have had success using pin 12 (+PaperEnd)
121 * instead. This driver searches for the zero crossing signal on either
122 * pin 17 or pin 12, so it should work with either cable configuration.
123 * My suggestion would be to start by making the cable so that the zero
124 * crossing signal goes to pin 12 on the parallel port.
126 * The zero crossing signal is used to synchronize transmission to the
127 * zero crossings of the AC line, as detailed in the X-10 documentation.
128 * It would be nice if one could generate interrupts with this signal,
129 * however one needs interrupts on both the rising and falling edges,
130 * and the -ACK signal to the parallel port interrupts only on the falling
131 * edge, so it can't be done without additional hardware.
133 * In this driver, the transmit function is performed in a non-interrupt-driven
134 * fashion, by polling the zero crossing signal to determine when a transition
135 * has occurred. This wastes CPU time during transmission, but it seems like
136 * the best that can be done without additional hardware. One problem with
137 * the scheme is that preemption of the CPU during transmission can cause loss
138 * of sync. The driver tries to catch this, by noticing that a long delay
139 * loop has somehow become foreshortened, and the transmission is aborted with
140 * an error return. It is up to the user level software to handle this
141 * situation (most likely by retrying the transmission).
144 #include <sys/param.h>
145 #include <sys/systm.h>
146 #include <sys/conf.h>
147 #include <sys/kernel.h>
149 #include <sys/syslog.h>
150 #include <sys/select.h>
151 #include <sys/poll.h>
154 #include <sys/time.h>
155 #endif /* HIRESTIME */
157 #include <bus/isa/i386/isa_device.h>
160 * Transmission is done by calling write() to send three byte packets of data.
161 * The first byte contains a four bit house code (0=A to 15=P).
162 * The second byte contains five bit unit/key code (0=unit 1 to 15=unit 16,
163 * 16=All Units Off to 31 = Status Request). The third byte specifies
164 * the number of times the packet is to be transmitted without any
165 * gaps between successive transmissions. Normally this is 2, as per
166 * the X-10 documentation, but sometimes (e.g. for bright and dim codes)
167 * it can be another value. Each call to write can specify an arbitrary
168 * number of data bytes. An incomplete packet is buffered until a subsequent
169 * call to write() provides data to complete it. At most one packet will
170 * actually be processed in any call to write(). Successive calls to write()
171 * leave a three-cycle gap between transmissions, per the X-10 documentation.
173 * Reception is done using read().
174 * The driver produces a series of three-character packets.
175 * In each packet, the first character consists of flags,
176 * the second character is a four bit house code (0-15),
177 * and the third character is a five bit key/function code (0-31).
178 * The flags are the following:
181 #define TW_RCV_LOCAL 1 /* The packet arrived during a local transmission */
182 #define TW_RCV_ERROR 2 /* An invalid/corrupted packet was received */
185 * IBM PC parallel port definitions relevant to TW523
188 #define tw_data 0 /* Data to tw523 (R/W) */
190 #define tw_status 1 /* Status of tw523 (R) */
191 #define TWS_RDATA 0x40 /* tw523 receive data */
192 #define TWS_OUT 0x20 /* pin 12, out of paper */
194 #define tw_control 2 /* Control tw523 (R/W) */
195 #define TWC_SYNC 0x08 /* tw523 sync (pin 17) */
196 #define TWC_ENA 0x10 /* tw523 interrupt enable */
199 * Miscellaneous defines
202 #define TWUNIT(dev) (minor(dev)) /* Extract unit number from device */
204 static int twprobe(struct isa_device *idp);
205 static int twattach(struct isa_device *idp);
207 struct isa_driver twdriver = {
208 twprobe, twattach, "tw"
211 static d_open_t twopen;
212 static d_close_t twclose;
213 static d_read_t twread;
214 static d_write_t twwrite;
215 static d_poll_t twpoll;
217 #define CDEV_MAJOR 19
218 static struct cdevsw tw_cdevsw = {
220 /* maj */ CDEV_MAJOR,
232 /* strategy */ nostrategy,
238 * Software control structure for TW523
241 #define TWS_XMITTING 1 /* Transmission in progress */
242 #define TWS_RCVING 2 /* Reception in progress */
243 #define TWS_WANT 4 /* A process wants received data */
244 #define TWS_OPEN 8 /* Is it currently open? */
246 #define TW_SIZE 3*60 /* Enough for about 10 sec. of input */
247 #define TW_MIN_DELAY 1500 /* Ignore interrupts of lesser latency */
249 static struct tw_sc {
250 u_int sc_port; /* I/O Port */
251 u_int sc_state; /* Current software control state */
252 struct selinfo sc_selp; /* Information for select() */
253 u_char sc_xphase; /* Current state of sync (for transmitter) */
254 u_char sc_rphase; /* Current state of sync (for receiver) */
255 u_char sc_flags; /* Flags for current reception */
256 short sc_rcount; /* Number of bits received so far */
257 int sc_bits; /* Bits received so far */
258 u_char sc_pkt[3]; /* Packet not yet transmitted */
259 short sc_pktsize; /* How many bytes in the packet? */
260 u_char sc_buf[TW_SIZE]; /* We buffer our own input */
261 int sc_nextin; /* Next free slot in circular buffer */
262 int sc_nextout; /* First used slot in circular buffer */
263 /* Callout for canceling our abortrcv timeout */
264 struct callout_handle abortrcv_ch;
266 int sc_xtimes[22]; /* Times for bits in current xmit packet */
267 int sc_rtimes[22]; /* Times for bits in current rcv packet */
268 int sc_no_rcv; /* number of interrupts received */
269 #define SC_RCV_TIME_LEN 128
270 int sc_rcv_time[SC_RCV_TIME_LEN]; /* usec time stamp on interrupt */
271 #endif /* HIRESTIME */
274 static int tw_zcport; /* offset of port for zero crossing signal */
275 static int tw_zcmask; /* mask for the zero crossing signal */
277 static void twdelay25(void);
278 static void twdelayn(int n);
279 static void twsetuptimes(int *a);
280 static int wait_for_zero(struct tw_sc *sc);
281 static int twputpkt(struct tw_sc *sc, u_char *p);
282 static ointhand2_t twintr;
283 static int twgetbytes(struct tw_sc *sc, u_char *p, int cnt);
284 static timeout_t twabortrcv;
285 static int twsend(struct tw_sc *sc, int h, int k, int cnt);
286 static int next_zero(struct tw_sc *sc);
287 static int twchecktime(int target, int tol);
288 static void twdebugtimes(struct tw_sc *sc);
291 * Counter value for delay loop.
292 * It is adjusted by twprobe so that the delay loop takes about 25us.
295 #define TWDELAYCOUNT 161 /* Works on my 486DX/33 */
296 static int twdelaycount;
299 * Twdelay25 is used for very short delays of about 25us.
300 * It is implemented with a calibrated delay loop, and should be
301 * fairly accurate ... unless we are preempted by an interrupt.
303 * We use this to wait for zero crossings because the X-10 specs say we
304 * are supposed to assert carrier within 25us when one happens.
305 * I don't really believe we can do this, but the X-10 devices seem to be
309 static void twdelay25(void)
312 for(cnt = twdelaycount; cnt; cnt--); /* Should take about 25us */
316 * Twdelayn is used to time the length of the 1ms carrier pulse.
317 * This is not very critical, but if we have high-resolution time-of-day
318 * we check it every apparent 200us to make sure we don't get too far off
319 * if we happen to be interrupted during the delay.
322 static void twdelayn(int n)
330 #endif /* HIRESTIME */
338 if(d >= 0 && d < 1000000) return;
340 #endif /* HIRESTIME */
344 static int twprobe(idp)
345 struct isa_device *idp;
353 cdevsw_add(&tw_cdevsw);
354 sc.sc_port = idp->id_iobase;
355 /* Search for the zero crossing signal at ports, bit combinations. */
356 tw_zcport = tw_control;
357 tw_zcmask = TWC_SYNC;
358 sc.sc_xphase = inb(idp->id_iobase + tw_zcport) & tw_zcmask;
359 if(wait_for_zero(&sc) < 0) {
360 tw_zcport = tw_status;
362 sc.sc_xphase = inb(idp->id_iobase + tw_zcport) & tw_zcmask;
364 if(wait_for_zero(&sc) < 0)
367 * Iteratively check the timing of a few sync transitions, and adjust
368 * the loop delay counter, if necessary, to bring the timing reported
369 * by wait_for_zero() close to HALFCYCLE. Give up if anything
370 * ridiculous happens.
372 if(twdelaycount == 0) { /* Only adjust timing for first unit */
373 twdelaycount = TWDELAYCOUNT;
374 for(tries = 0; tries < 10; tries++) {
375 sc.sc_xphase = inb(idp->id_iobase + tw_zcport) & tw_zcmask;
376 if(wait_for_zero(&sc) >= 0) {
377 d = wait_for_zero(&sc);
378 if(d <= HALFCYCLE/100 || d >= HALFCYCLE*100) {
382 twdelaycount = (twdelaycount * d)/HALFCYCLE;
387 * Now do a final check, just to make sure
389 sc.sc_xphase = inb(idp->id_iobase + tw_zcport) & tw_zcmask;
390 if(wait_for_zero(&sc) >= 0) {
391 d = wait_for_zero(&sc);
392 if(d <= (HALFCYCLE * 110)/100 && d >= (HALFCYCLE * 90)/100) return(8);
397 static int twattach(idp)
398 struct isa_device *idp;
403 idp->id_ointr = twintr;
404 sc = &tw_sc[unit = idp->id_unit];
405 sc->sc_port = idp->id_iobase;
408 callout_handle_init(&sc->abortrcv_ch);
409 make_dev(&tw_cdevsw, unit, 0, 0, 0600, "tw%d", unit);
413 int twopen(dev, flag, mode, td)
419 struct tw_sc *sc = &tw_sc[TWUNIT(dev)];
423 if(sc->sc_state == 0) {
424 sc->sc_state = TWS_OPEN;
425 sc->sc_nextin = sc->sc_nextout = 0;
427 outb(sc->sc_port+tw_control, TWC_ENA);
433 int twclose(dev, flag, mode, td)
439 struct tw_sc *sc = &tw_sc[TWUNIT(dev)];
444 outb(sc->sc_port+tw_control, 0);
449 int twread(dev, uio, ioflag)
455 struct tw_sc *sc = &tw_sc[TWUNIT(dev)];
459 cnt = MIN(uio->uio_resid, 3);
460 if((error = twgetbytes(sc, buf, cnt)) == 0) {
461 error = uiomove(buf, cnt, uio);
467 int twwrite(dev, uio, ioflag)
473 int house, key, reps;
477 sc = &tw_sc[TWUNIT(dev)];
479 * Note: Although I had intended to allow concurrent transmitters,
480 * there is a potential problem here if two processes both write
481 * into the sc_pkt buffer at the same time. The following code
482 * is an additional critical section that needs to be synchronized.
485 cnt = MIN(3 - sc->sc_pktsize, uio->uio_resid);
486 error = uiomove(&(sc->sc_pkt[sc->sc_pktsize]), cnt, uio);
491 sc->sc_pktsize += cnt;
492 if(sc->sc_pktsize < 3) { /* Only transmit 3-byte packets */
498 * Collect house code, key code, and rep count, and check for sanity.
500 house = sc->sc_pkt[0];
502 reps = sc->sc_pkt[2];
503 if(house >= 16 || key >= 32) {
508 * Synchronize with the receiver operating in the bottom half, and
509 * also with concurrent transmitters.
510 * We don't want to interfere with a packet currently being received,
511 * and we would like the receiver to recognize when a packet has
512 * originated locally.
514 while(sc->sc_state & (TWS_RCVING | TWS_XMITTING)) {
515 error = tsleep((caddr_t)sc, PCATCH, "twwrite", 0);
521 sc->sc_state |= TWS_XMITTING;
523 * Everything looks OK, let's do the transmission.
525 splx(s); /* Enable interrupts because this takes a LONG time */
526 error = twsend(sc, house, key, reps);
528 sc->sc_state &= ~TWS_XMITTING;
531 if(error) return(EIO);
536 * Determine if there is data available for reading
539 int twpoll(dev, events, td)
548 sc = &tw_sc[TWUNIT(dev)];
550 /* XXX is this correct? the original code didn't test select rw mode!! */
551 if (events & (POLLIN | POLLRDNORM)) {
552 if(sc->sc_nextin != sc->sc_nextout)
553 revents |= events & (POLLIN | POLLRDNORM);
555 selrecord(td, &sc->sc_selp);
565 #define X10_START_LENGTH 4
566 static char X10_START[] = { 1, 1, 1, 0 };
569 * Each bit of the 4-bit house code and 5-bit key code
570 * is transmitted twice, once in true form, and then in
571 * complemented form. This is already taken into account
572 * in the following tables.
575 #define X10_HOUSE_LENGTH 8
576 static char X10_HOUSE[16][8] = {
577 { 0, 1, 1, 0, 1, 0, 0, 1 }, /* A = 0110 */
578 { 1, 0, 1, 0, 1, 0, 0, 1 }, /* B = 1110 */
579 { 0, 1, 0, 1, 1, 0, 0, 1 }, /* C = 0010 */
580 { 1, 0, 0, 1, 1, 0, 0, 1 }, /* D = 1010 */
581 { 0, 1, 0, 1, 0, 1, 1, 0 }, /* E = 0001 */
582 { 1, 0, 0, 1, 0, 1, 1, 0 }, /* F = 1001 */
583 { 0, 1, 1, 0, 0, 1, 1, 0 }, /* G = 0101 */
584 { 1, 0, 1, 0, 0, 1, 1, 0 }, /* H = 1101 */
585 { 0, 1, 1, 0, 1, 0, 1, 0 }, /* I = 0111 */
586 { 1, 0, 1, 0, 1, 0, 1, 0 }, /* J = 1111 */
587 { 0, 1, 0, 1, 1, 0, 1, 0 }, /* K = 0011 */
588 { 1, 0, 0, 1, 1, 0, 1, 0 }, /* L = 1011 */
589 { 0, 1, 0, 1, 0, 1, 0, 1 }, /* M = 0000 */
590 { 1, 0, 0, 1, 0, 1, 0, 1 }, /* N = 1000 */
591 { 0, 1, 1, 0, 0, 1, 0, 1 }, /* O = 0100 */
592 { 1, 0, 1, 0, 0, 1, 0, 1 } /* P = 1100 */
595 #define X10_KEY_LENGTH 10
596 static char X10_KEY[32][10] = {
597 { 0, 1, 1, 0, 1, 0, 0, 1, 0, 1 }, /* 01100 => 1 */
598 { 1, 0, 1, 0, 1, 0, 0, 1, 0, 1 }, /* 11100 => 2 */
599 { 0, 1, 0, 1, 1, 0, 0, 1, 0, 1 }, /* 00100 => 3 */
600 { 1, 0, 0, 1, 1, 0, 0, 1, 0, 1 }, /* 10100 => 4 */
601 { 0, 1, 0, 1, 0, 1, 1, 0, 0, 1 }, /* 00010 => 5 */
602 { 1, 0, 0, 1, 0, 1, 1, 0, 0, 1 }, /* 10010 => 6 */
603 { 0, 1, 1, 0, 0, 1, 1, 0, 0, 1 }, /* 01010 => 7 */
604 { 1, 0, 1, 0, 0, 1, 1, 0, 0, 1 }, /* 11010 => 8 */
605 { 0, 1, 1, 0, 1, 0, 1, 0, 0, 1 }, /* 01110 => 9 */
606 { 1, 0, 1, 0, 1, 0, 1, 0, 0, 1 }, /* 11110 => 10 */
607 { 0, 1, 0, 1, 1, 0, 1, 0, 0, 1 }, /* 00110 => 11 */
608 { 1, 0, 0, 1, 1, 0, 1, 0, 0, 1 }, /* 10110 => 12 */
609 { 0, 1, 0, 1, 0, 1, 0, 1, 0, 1 }, /* 00000 => 13 */
610 { 1, 0, 0, 1, 0, 1, 0, 1, 0, 1 }, /* 10000 => 14 */
611 { 0, 1, 1, 0, 0, 1, 0, 1, 0, 1 }, /* 01000 => 15 */
612 { 1, 0, 1, 0, 0, 1, 0, 1, 0, 1 }, /* 11000 => 16 */
613 { 0, 1, 0, 1, 0, 1, 0, 1, 1, 0 }, /* 00001 => All Units Off */
614 { 0, 1, 0, 1, 0, 1, 1, 0, 1, 0 }, /* 00011 => All Units On */
615 { 0, 1, 0, 1, 1, 0, 0, 1, 1, 0 }, /* 00101 => On */
616 { 0, 1, 0, 1, 1, 0, 1, 0, 1, 0 }, /* 00111 => Off */
617 { 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 }, /* 01001 => Dim */
618 { 0, 1, 1, 0, 0, 1, 1, 0, 1, 0 }, /* 01011 => Bright */
619 { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0 }, /* 01101 => All LIGHTS Off */
620 { 0, 1, 1, 0, 1, 0, 1, 0, 1, 0 }, /* 01111 => Extended Code */
621 { 1, 0, 0, 1, 0, 1, 0, 1, 1, 0 }, /* 10001 => Hail Request */
622 { 1, 0, 0, 1, 0, 1, 1, 0, 1, 0 }, /* 10011 => Hail Acknowledge */
623 { 1, 0, 0, 1, 1, 0, 0, 1, 1, 0 }, /* 10101 => Preset Dim 0 */
624 { 1, 0, 0, 1, 1, 0, 1, 0, 1, 0 }, /* 10111 => Preset Dim 1 */
625 { 1, 0, 1, 0, 0, 1, 0, 1, 0, 1 }, /* 11000 => Extended Data (analog) */
626 { 1, 0, 1, 0, 0, 1, 1, 0, 1, 0 }, /* 11011 => Status = on */
627 { 1, 0, 1, 0, 1, 0, 0, 1, 1, 0 }, /* 11101 => Status = off */
628 { 1, 0, 1, 0, 1, 0, 1, 0, 1, 0 } /* 11111 => Status request */
632 * Tables for mapping received X-10 code back to house/key number.
635 static short X10_HOUSE_INV[16] = {
636 12, 4, 2, 10, 14, 6, 0, 8,
637 13, 5, 3, 11, 15, 7, 1, 9
640 static short X10_KEY_INV[32] = {
641 12, 16, 4, 17, 2, 18, 10, 19,
642 14, 20, 6, 21, 0, 22, 8, 23,
643 13, 24, 5, 25, 3, 26, 11, 27,
644 15, 28, 7, 29, 1, 30, 9, 31
647 static char *X10_KEY_LABEL[32] = {
676 "Extended Data (analog)",
682 * Transmit a packet containing house code h and key code k
685 #define TWRETRY 10 /* Try 10 times to sync with AC line */
687 static int twsend(sc, h, k, cnt)
692 int port = sc->sc_port;
695 * Make sure we get a reliable sync with a power line zero crossing
697 for(i = 0; i < TWRETRY; i++) {
698 if(wait_for_zero(sc) > 100) goto insync;
700 log(LOG_ERR, "TWXMIT: failed to sync.\n");
705 * Be sure to leave 3 cycles space between transmissions
707 for(i = 6; i > 0; i--)
708 if(next_zero(sc) < 0) return(-1);
710 * The packet is transmitted cnt times, with no gaps.
714 * Transmit the start code
716 for(i = 0; i < X10_START_LENGTH; i++) {
717 outb(port+tw_data, X10_START[i] ? 0xff : 0x00); /* Waste no time! */
719 if(i == 0) twsetuptimes(sc->sc_xtimes);
720 if(twchecktime(sc->sc_xtimes[i], HALFCYCLE/20) == 0) {
721 outb(port+tw_data, 0);
724 #endif /* HIRESTIME */
725 twdelayn(1000); /* 1ms pulse width */
726 outb(port+tw_data, 0);
727 if(next_zero(sc) < 0) return(-1);
730 * Transmit the house code
732 for(i = 0; i < X10_HOUSE_LENGTH; i++) {
733 outb(port+tw_data, X10_HOUSE[h][i] ? 0xff : 0x00); /* Waste no time! */
735 if(twchecktime(sc->sc_xtimes[i+X10_START_LENGTH], HALFCYCLE/20) == 0) {
736 outb(port+tw_data, 0);
739 #endif /* HIRESTIME */
740 twdelayn(1000); /* 1ms pulse width */
741 outb(port+tw_data, 0);
742 if(next_zero(sc) < 0) return(-1);
745 * Transmit the unit/key code
747 for(i = 0; i < X10_KEY_LENGTH; i++) {
748 outb(port+tw_data, X10_KEY[k][i] ? 0xff : 0x00);
750 if(twchecktime(sc->sc_xtimes[i+X10_START_LENGTH+X10_HOUSE_LENGTH],
751 HALFCYCLE/20) == 0) {
752 outb(port+tw_data, 0);
755 #endif /* HIRESTIME */
756 twdelayn(1000); /* 1ms pulse width */
757 outb(port+tw_data, 0);
758 if(next_zero(sc) < 0) return(-1);
765 * Waste CPU cycles to get in sync with a power line zero crossing.
766 * The value returned is roughly how many microseconds we wasted before
767 * seeing the transition. To avoid wasting time forever, we give up after
768 * waiting patiently for 1/4 sec (15 power line cycles at 60 Hz),
769 * which is more than the 11 cycles it takes to transmit a full
773 static int wait_for_zero(sc)
776 int i, old, new, max;
777 int port = sc->sc_port + tw_zcport;
780 max = 10000; /* 10000 * 25us = 0.25 sec */
783 new = inb(port) & tw_zcmask;
795 * Wait for the next zero crossing transition, and if we don't have
796 * high-resolution time-of-day, check to see that the zero crossing
797 * appears to be arriving on schedule.
798 * We expect to be waiting almost a full half-cycle (8.333ms-1ms = 7.333ms).
799 * If we don't seem to wait very long, something is wrong (like we got
800 * preempted!) and we should abort the transmission because
801 * there's no telling how long it's really been since the
802 * last bit was transmitted.
805 static int next_zero(sc)
810 if((d = wait_for_zero(sc)) < 0) {
812 if((d = wait_for_zero(sc)) < 6000 || d > 8500) {
813 /* No less than 6.0ms, no more than 8.5ms */
814 #endif /* HIRESTIME */
815 log(LOG_ERR, "TWXMIT framing error: %d\n", d);
822 * Put a three-byte packet into the circular buffer
823 * Should be called at priority spltty()
826 static int twputpkt(sc, p)
832 for(i = 0; i < 3; i++) {
833 next = sc->sc_nextin+1;
834 if(next >= TW_SIZE) next = 0;
835 if(next == sc->sc_nextout) { /* Buffer full */
837 log(LOG_ERR, "TWRCV: Buffer overrun\n");
841 sc->sc_buf[sc->sc_nextin] = *p++;
842 sc->sc_nextin = next;
844 if(sc->sc_state & TWS_WANT) {
845 sc->sc_state &= ~TWS_WANT;
846 wakeup((caddr_t)(&sc->sc_buf));
848 selwakeup(&sc->sc_selp);
853 * Get bytes from the circular buffer
854 * Should be called at priority spltty()
857 static int twgetbytes(sc, p, cnt)
865 while(sc->sc_nextin == sc->sc_nextout) { /* Buffer empty */
866 sc->sc_state |= TWS_WANT;
867 error = tsleep((caddr_t)(&sc->sc_buf), PCATCH, "twread", 0);
872 *p++ = sc->sc_buf[sc->sc_nextout++];
873 if(sc->sc_nextout >= TW_SIZE) sc->sc_nextout = 0;
879 * Abort reception that has failed to complete in the required time.
886 struct tw_sc *sc = arg;
891 sc->sc_state &= ~TWS_RCVING;
892 /* simply ignore single isolated interrupts. */
893 if (sc->sc_no_rcv > 1) {
894 sc->sc_flags |= TW_RCV_ERROR;
895 pkt[0] = sc->sc_flags;
898 log(LOG_ERR, "TWRCV: aborting (%x, %d)\n", sc->sc_bits, sc->sc_rcount);
906 tw_is_within(int value, int expected, int tolerance)
909 diff = value - expected;
912 if (diff < tolerance)
918 * This routine handles interrupts that occur when there is a falling
919 * transition on the RX input. There isn't going to be a transition
920 * on every bit (some are zero), but if we are smart and keep track of
921 * how long it's been since the last interrupt (via the zero crossing
922 * detect line and/or high-resolution time-of-day routine), we can
923 * reconstruct the transmission without having to poll.
926 static void twintr(unit)
929 struct tw_sc *sc = &tw_sc[unit];
938 * Ignore any interrupts that occur if the device is not open.
940 if(sc->sc_state == 0) return;
941 newphase = inb(port + tw_zcport) & tw_zcmask;
946 * If we aren't currently receiving a packet, set up a new packet
947 * and put in the first "1" bit that has just arrived.
948 * Arrange for the reception to be aborted if too much time goes by.
950 if((sc->sc_state & TWS_RCVING) == 0) {
952 twsetuptimes(sc->sc_rtimes);
953 #endif /* HIRESTIME */
954 sc->sc_state |= TWS_RCVING;
956 if(sc->sc_state & TWS_XMITTING) sc->sc_flags = TW_RCV_LOCAL;
957 else sc->sc_flags = 0;
959 sc->sc_rphase = newphase;
960 /* 3 cycles of silence = 3/60 = 1/20 = 50 msec */
961 sc->abortrcv_ch = timeout(twabortrcv, (caddr_t)sc, hz/20);
962 sc->sc_rcv_time[0] = tv.tv_usec;
966 untimeout(twabortrcv, (caddr_t)sc, sc->abortrcv_ch);
967 sc->abortrcv_ch = timeout(twabortrcv, (caddr_t)sc, hz/20);
968 newphase = inb(port + tw_zcport) & tw_zcmask;
970 /* enforce a minimum delay since the last interrupt */
971 delay = tv.tv_usec - sc->sc_rcv_time[sc->sc_no_rcv - 1];
974 if (delay < TW_MIN_DELAY)
977 sc->sc_rcv_time[sc->sc_no_rcv] = tv.tv_usec;
978 if (sc->sc_rcv_time[sc->sc_no_rcv] < sc->sc_rcv_time[0])
979 sc->sc_rcv_time[sc->sc_no_rcv] += 1000000;
984 * The second and third bits are a special case.
986 if (sc->sc_rcount < 3) {
989 tw_is_within(delay, HALFCYCLE, HALFCYCLE / 6)
991 newphase != sc->sc_rphase
997 * Invalid start code -- abort reception.
999 sc->sc_state &= ~TWS_RCVING;
1000 sc->sc_flags |= TW_RCV_ERROR;
1001 untimeout(twabortrcv, (caddr_t)sc, sc->abortrcv_ch);
1002 log(LOG_ERR, "TWRCV: Invalid start code\n");
1007 if(sc->sc_rcount == 3) {
1009 * We've gotten three "1" bits in a row. The start code
1010 * is really 1110, but this might be followed by a zero
1011 * bit from the house code, so if we wait any longer we
1012 * might be confused about the first house code bit.
1013 * So, we guess that the start code is correct and insert
1014 * the trailing zero without actually having seen it.
1015 * We don't change sc_rphase in this case, because two
1016 * bit arrivals in a row preserve parity.
1022 * Update sc_rphase to the current phase before returning.
1024 sc->sc_rphase = newphase;
1029 * Now figure out what the current bit is that just arrived.
1030 * The X-10 protocol transmits each data bit twice: once in
1031 * true form and once in complemented form on the next half
1032 * cycle. So, there will be at least one interrupt per bit.
1033 * By comparing the phase we see at the time of the interrupt
1034 * with the saved sc_rphase, we can tell on which half cycle
1035 * the interrupt occrred. This assumes, of course, that the
1036 * packet is well-formed. We do the best we can at trying to
1037 * catch errors by aborting if too much time has gone by, and
1038 * by tossing out a packet if too many bits arrive, but the
1039 * whole scheme is probably not as robust as if we had a nice
1040 * interrupt on every half cycle of the power line.
1041 * If we have high-resolution time-of-day routines, then we
1042 * can do a bit more sanity checking.
1046 * A complete packet is 22 half cycles.
1048 if(sc->sc_rcount <= 20) {
1050 int bit = 0, last_bit;
1051 if (sc->sc_rcount == 4)
1052 last_bit = 1; /* Start (1110) ends in 10, a 'one' code. */
1054 last_bit = sc->sc_bits & 0x1;
1055 if ( ( (last_bit == 1)
1056 && (tw_is_within(delay, HALFCYCLE * 2, HALFCYCLE / 6)))
1057 || ( (last_bit == 0)
1058 && (tw_is_within(delay, HALFCYCLE * 1, HALFCYCLE / 6))))
1060 else if ( ( (last_bit == 1)
1061 && (tw_is_within(delay, HALFCYCLE * 3, HALFCYCLE / 6)))
1062 || ( (last_bit == 0)
1063 && (tw_is_within(delay, HALFCYCLE * 2, HALFCYCLE / 6))))
1066 sc->sc_flags |= TW_RCV_ERROR;
1067 log(LOG_ERR, "TWRCV: %d cycle after %d bit, delay %d%%\n",
1068 sc->sc_rcount, last_bit, 100 * delay / HALFCYCLE);
1070 sc->sc_bits = (sc->sc_bits << 1) | bit;
1072 sc->sc_bits = (sc->sc_bits << 1)
1073 | ((newphase == sc->sc_rphase) ? 0x0 : 0x1);
1074 #endif /* HIRESTIME */
1077 if(sc->sc_rcount >= 22 || sc->sc_flags & TW_RCV_ERROR) {
1078 if(sc->sc_rcount != 22) {
1079 sc->sc_flags |= TW_RCV_ERROR;
1080 pkt[0] = sc->sc_flags;
1081 pkt[1] = pkt[2] = 0;
1083 pkt[0] = sc->sc_flags;
1084 pkt[1] = X10_HOUSE_INV[(sc->sc_bits & 0x1e0) >> 5];
1085 pkt[2] = X10_KEY_INV[sc->sc_bits & 0x1f];
1087 sc->sc_state &= ~TWS_RCVING;
1089 untimeout(twabortrcv, (caddr_t)sc, sc->abortrcv_ch);
1090 if(sc->sc_flags & TW_RCV_ERROR) {
1091 log(LOG_ERR, "TWRCV: invalid packet: (%d, %x) %c %s\n",
1092 sc->sc_rcount, sc->sc_bits, 'A' + pkt[1], X10_KEY_LABEL[pkt[2]]);
1095 /* log(LOG_ERR, "TWRCV: valid packet: (%d, %x) %c %s\n",
1096 sc->sc_rcount, sc->sc_bits, 'A' + pkt[1], X10_KEY_LABEL[pkt[2]]); */
1099 wakeup((caddr_t)sc);
1103 static void twdebugtimes(struct tw_sc *sc)
1106 for (i = 0; (i < sc->sc_no_rcv) && (i < SC_RCV_TIME_LEN); i++)
1107 log(LOG_ERR, "TWRCV: interrupt %2d: %d\t%d%%\n", i, sc->sc_rcv_time[i],
1108 (sc->sc_rcv_time[i] - sc->sc_rcv_time[(i?i-1:0)])*100/HALFCYCLE);
1113 * Initialize an array of 22 times, starting from the current
1114 * microtime and continuing for the next 21 half cycles.
1115 * We use the times as a reference to make sure transmission
1116 * or reception is on schedule.
1119 static void twsetuptimes(int *a)
1126 for(i = 0; i < 22; i++) {
1129 if(t >= 1000000) t -= 1000000;
1134 * Check the current time against a slot in a previously set up
1135 * timing array, and make sure that it looks like we are still
1139 static int twchecktime(int target, int tol)
1146 d = (target - t) >= 0 ? (target - t) : (t - target);
1147 if(d > 500000) d = 1000000-d;
1148 if(d <= tol && d >= -tol) {
1154 #endif /* HIRESTIME */