1/*
2 * lirc_serial.c
3 *
4 * lirc_serial - Device driver that records pulse- and pause-lengths
5 *	       (space-lengths) between DDCD event on a serial port.
6 *
7 * Copyright (C) 1996,97 Ralph Metzler <rjkm@thp.uni-koeln.de>
8 * Copyright (C) 1998 Trent Piepho <xyzzy@u.washington.edu>
9 * Copyright (C) 1998 Ben Pfaff <blp@gnu.org>
10 * Copyright (C) 1999 Christoph Bartelmus <lirc@bartelmus.de>
11 * Copyright (C) 2007 Andrei Tanas <andrei@tanas.ca> (suspend/resume support)
12 *  This program is free software; you can redistribute it and/or modify
13 *  it under the terms of the GNU General Public License as published by
14 *  the Free Software Foundation; either version 2 of the License, or
15 *  (at your option) any later version.
16 *
17 *  This program is distributed in the hope that it will be useful,
18 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20 *  GNU General Public License for more details.
21 *
22 *  You should have received a copy of the GNU General Public License
23 *  along with this program; if not, write to the Free Software
24 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25 *
26 */
27
28/*
29 * Steve's changes to improve transmission fidelity:
30 *   - for systems with the rdtsc instruction and the clock counter, a
31 *     send_pule that times the pulses directly using the counter.
32 *     This means that the LIRC_SERIAL_TRANSMITTER_LATENCY fudge is
33 *     not needed. Measurement shows very stable waveform, even where
34 *     PCI activity slows the access to the UART, which trips up other
35 *     versions.
36 *   - For other system, non-integer-microsecond pulse/space lengths,
37 *     done using fixed point binary. So, much more accurate carrier
38 *     frequency.
39 *   - fine tuned transmitter latency, taking advantage of fractional
40 *     microseconds in previous change
41 *   - Fixed bug in the way transmitter latency was accounted for by
42 *     tuning the pulse lengths down - the send_pulse routine ignored
43 *     this overhead as it timed the overall pulse length - so the
44 *     pulse frequency was right but overall pulse length was too
45 *     long. Fixed by accounting for latency on each pulse/space
46 *     iteration.
47 *
48 * Steve Davies <steve@daviesfam.org>  July 2001
49 */
50
51#include <linux/module.h>
52#include <linux/errno.h>
53#include <linux/signal.h>
54#include <linux/sched.h>
55#include <linux/fs.h>
56#include <linux/interrupt.h>
57#include <linux/ioport.h>
58#include <linux/kernel.h>
59#include <linux/serial_reg.h>
60#include <linux/time.h>
61#include <linux/string.h>
62#include <linux/types.h>
63#include <linux/wait.h>
64#include <linux/mm.h>
65#include <linux/delay.h>
66#include <linux/poll.h>
67#include <linux/platform_device.h>
68
69#include <linux/io.h>
70#include <linux/irq.h>
71#include <linux/fcntl.h>
72#include <linux/spinlock.h>
73
74#ifdef CONFIG_LIRC_SERIAL_NSLU2
75#include <asm/hardware.h>
76#endif
77/* From Intel IXP42X Developer's Manual (#252480-005): */
78/* ftp://download.intel.com/design/network/manuals/25248005.pdf */
79#define UART_IE_IXP42X_UUE   0x40 /* IXP42X UART Unit enable */
80#define UART_IE_IXP42X_RTOIE 0x10 /* IXP42X Receiver Data Timeout int.enable */
81
82#include <media/lirc.h>
83#include <media/lirc_dev.h>
84
85#define LIRC_DRIVER_NAME "lirc_serial"
86
87struct lirc_serial {
88	int signal_pin;
89	int signal_pin_change;
90	u8 on;
91	u8 off;
92	long (*send_pulse)(unsigned long length);
93	void (*send_space)(long length);
94	int features;
95	spinlock_t lock;
96};
97
98#define LIRC_HOMEBREW		0
99#define LIRC_IRDEO		1
100#define LIRC_IRDEO_REMOTE	2
101#define LIRC_ANIMAX		3
102#define LIRC_IGOR		4
103#define LIRC_NSLU2		5
104
105/*** module parameters ***/
106static int type;
107static int io;
108static int irq;
109static bool iommap;
110static int ioshift;
111static bool softcarrier = 1;
112static bool share_irq;
113static bool debug;
114static int sense = -1;	/* -1 = auto, 0 = active high, 1 = active low */
115static bool txsense;	/* 0 = active high, 1 = active low */
116
117#define dprintk(fmt, args...)					\
118	do {							\
119		if (debug)					\
120			printk(KERN_DEBUG LIRC_DRIVER_NAME ": "	\
121			       fmt, ## args);			\
122	} while (0)
123
124/* forward declarations */
125static long send_pulse_irdeo(unsigned long length);
126static long send_pulse_homebrew(unsigned long length);
127static void send_space_irdeo(long length);
128static void send_space_homebrew(long length);
129
130static struct lirc_serial hardware[] = {
131	[LIRC_HOMEBREW] = {
132		.signal_pin        = UART_MSR_DCD,
133		.signal_pin_change = UART_MSR_DDCD,
134		.on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
135		.off = (UART_MCR_RTS | UART_MCR_OUT2),
136		.send_pulse = send_pulse_homebrew,
137		.send_space = send_space_homebrew,
138#ifdef CONFIG_LIRC_SERIAL_TRANSMITTER
139		.features    = (LIRC_CAN_SET_SEND_DUTY_CYCLE |
140				LIRC_CAN_SET_SEND_CARRIER |
141				LIRC_CAN_SEND_PULSE | LIRC_CAN_REC_MODE2)
142#else
143		.features    = LIRC_CAN_REC_MODE2
144#endif
145	},
146
147	[LIRC_IRDEO] = {
148		.signal_pin        = UART_MSR_DSR,
149		.signal_pin_change = UART_MSR_DDSR,
150		.on  = UART_MCR_OUT2,
151		.off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
152		.send_pulse  = send_pulse_irdeo,
153		.send_space  = send_space_irdeo,
154		.features    = (LIRC_CAN_SET_SEND_DUTY_CYCLE |
155				LIRC_CAN_SEND_PULSE | LIRC_CAN_REC_MODE2)
156	},
157
158	[LIRC_IRDEO_REMOTE] = {
159		.signal_pin        = UART_MSR_DSR,
160		.signal_pin_change = UART_MSR_DDSR,
161		.on  = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
162		.off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
163		.send_pulse  = send_pulse_irdeo,
164		.send_space  = send_space_irdeo,
165		.features    = (LIRC_CAN_SET_SEND_DUTY_CYCLE |
166				LIRC_CAN_SEND_PULSE | LIRC_CAN_REC_MODE2)
167	},
168
169	[LIRC_ANIMAX] = {
170		.signal_pin        = UART_MSR_DCD,
171		.signal_pin_change = UART_MSR_DDCD,
172		.on  = 0,
173		.off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
174		.send_pulse = NULL,
175		.send_space = NULL,
176		.features   = LIRC_CAN_REC_MODE2
177	},
178
179	[LIRC_IGOR] = {
180		.signal_pin        = UART_MSR_DSR,
181		.signal_pin_change = UART_MSR_DDSR,
182		.on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
183		.off = (UART_MCR_RTS | UART_MCR_OUT2),
184		.send_pulse = send_pulse_homebrew,
185		.send_space = send_space_homebrew,
186#ifdef CONFIG_LIRC_SERIAL_TRANSMITTER
187		.features    = (LIRC_CAN_SET_SEND_DUTY_CYCLE |
188				LIRC_CAN_SET_SEND_CARRIER |
189				LIRC_CAN_SEND_PULSE | LIRC_CAN_REC_MODE2)
190#else
191		.features    = LIRC_CAN_REC_MODE2
192#endif
193	},
194
195#ifdef CONFIG_LIRC_SERIAL_NSLU2
196	/*
197	 * Modified Linksys Network Storage Link USB 2.0 (NSLU2):
198	 * We receive on CTS of the 2nd serial port (R142,LHS), we
199	 * transmit with a IR diode between GPIO[1] (green status LED),
200	 * and ground (Matthias Goebl <matthias.goebl@goebl.net>).
201	 * See also http://www.nslu2-linux.org for this device
202	 */
203	[LIRC_NSLU2] = {
204		.signal_pin        = UART_MSR_CTS,
205		.signal_pin_change = UART_MSR_DCTS,
206		.on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
207		.off = (UART_MCR_RTS | UART_MCR_OUT2),
208		.send_pulse = send_pulse_homebrew,
209		.send_space = send_space_homebrew,
210#ifdef CONFIG_LIRC_SERIAL_TRANSMITTER
211		.features    = (LIRC_CAN_SET_SEND_DUTY_CYCLE |
212				LIRC_CAN_SET_SEND_CARRIER |
213				LIRC_CAN_SEND_PULSE | LIRC_CAN_REC_MODE2)
214#else
215		.features    = LIRC_CAN_REC_MODE2
216#endif
217	},
218#endif
219
220};
221
222#define RS_ISR_PASS_LIMIT 256
223
224/*
225 * A long pulse code from a remote might take up to 300 bytes.  The
226 * daemon should read the bytes as soon as they are generated, so take
227 * the number of keys you think you can push before the daemon runs
228 * and multiply by 300.  The driver will warn you if you overrun this
229 * buffer.  If you have a slow computer or non-busmastering IDE disks,
230 * maybe you will need to increase this.
231 */
232
233/* This MUST be a power of two!  It has to be larger than 1 as well. */
234
235#define RBUF_LEN 256
236
237static struct timeval lasttv = {0, 0};
238
239static struct lirc_buffer rbuf;
240
241static unsigned int freq = 38000;
242static unsigned int duty_cycle = 50;
243
244/* Initialized in init_timing_params() */
245static unsigned long period;
246static unsigned long pulse_width;
247static unsigned long space_width;
248
249#if defined(__i386__)
250/*
251 * From:
252 * Linux I/O port programming mini-HOWTO
253 * Author: Riku Saikkonen <Riku.Saikkonen@hut.fi>
254 * v, 28 December 1997
255 *
256 * [...]
257 * Actually, a port I/O instruction on most ports in the 0-0x3ff range
258 * takes almost exactly 1 microsecond, so if you're, for example, using
259 * the parallel port directly, just do additional inb()s from that port
260 * to delay.
261 * [...]
262 */
263/* transmitter latency 1.5625us 0x1.90 - this figure arrived at from
264 * comment above plus trimming to match actual measured frequency.
265 * This will be sensitive to cpu speed, though hopefully most of the 1.5us
266 * is spent in the uart access.  Still - for reference test machine was a
267 * 1.13GHz Athlon system - Steve
268 */
269
270/*
271 * changed from 400 to 450 as this works better on slower machines;
272 * faster machines will use the rdtsc code anyway
273 */
274#define LIRC_SERIAL_TRANSMITTER_LATENCY 450
275
276#else
277
278/* does anybody have information on other platforms ? */
279/* 256 = 1<<8 */
280#define LIRC_SERIAL_TRANSMITTER_LATENCY 256
281
282#endif  /* __i386__ */
283/*
284 * FIXME: should we be using hrtimers instead of this
285 * LIRC_SERIAL_TRANSMITTER_LATENCY nonsense?
286 */
287
288/* fetch serial input packet (1 byte) from register offset */
289static u8 sinp(int offset)
290{
291	if (iommap != 0)
292		/* the register is memory-mapped */
293		offset <<= ioshift;
294
295	return inb(io + offset);
296}
297
298/* write serial output packet (1 byte) of value to register offset */
299static void soutp(int offset, u8 value)
300{
301	if (iommap != 0)
302		/* the register is memory-mapped */
303		offset <<= ioshift;
304
305	outb(value, io + offset);
306}
307
308static void on(void)
309{
310#ifdef CONFIG_LIRC_SERIAL_NSLU2
311	/*
312	 * On NSLU2, we put the transmit diode between the output of the green
313	 * status LED and ground
314	 */
315	if (type == LIRC_NSLU2) {
316		gpio_line_set(NSLU2_LED_GRN, IXP4XX_GPIO_LOW);
317		return;
318	}
319#endif
320	if (txsense)
321		soutp(UART_MCR, hardware[type].off);
322	else
323		soutp(UART_MCR, hardware[type].on);
324}
325
326static void off(void)
327{
328#ifdef CONFIG_LIRC_SERIAL_NSLU2
329	if (type == LIRC_NSLU2) {
330		gpio_line_set(NSLU2_LED_GRN, IXP4XX_GPIO_HIGH);
331		return;
332	}
333#endif
334	if (txsense)
335		soutp(UART_MCR, hardware[type].on);
336	else
337		soutp(UART_MCR, hardware[type].off);
338}
339
340#ifndef MAX_UDELAY_MS
341#define MAX_UDELAY_US 5000
342#else
343#define MAX_UDELAY_US (MAX_UDELAY_MS*1000)
344#endif
345
346static void safe_udelay(unsigned long usecs)
347{
348	while (usecs > MAX_UDELAY_US) {
349		udelay(MAX_UDELAY_US);
350		usecs -= MAX_UDELAY_US;
351	}
352	udelay(usecs);
353}
354
355#ifdef USE_RDTSC
356/*
357 * This is an overflow/precision juggle, complicated in that we can't
358 * do long long divide in the kernel
359 */
360
361/*
362 * When we use the rdtsc instruction to measure clocks, we keep the
363 * pulse and space widths as clock cycles.  As this is CPU speed
364 * dependent, the widths must be calculated in init_port and ioctl
365 * time
366 */
367
368/* So send_pulse can quickly convert microseconds to clocks */
369static unsigned long conv_us_to_clocks;
370
371static int init_timing_params(unsigned int new_duty_cycle,
372		unsigned int new_freq)
373{
374	__u64 loops_per_sec, work;
375
376	duty_cycle = new_duty_cycle;
377	freq = new_freq;
378
379	loops_per_sec = __this_cpu_read(cpu.info.loops_per_jiffy);
380	loops_per_sec *= HZ;
381
382	/* How many clocks in a microsecond?, avoiding long long divide */
383	work = loops_per_sec;
384	work *= 4295;  /* 4295 = 2^32 / 1e6 */
385	conv_us_to_clocks = (work >> 32);
386
387	/*
388	 * Carrier period in clocks, approach good up to 32GHz clock,
389	 * gets carrier frequency within 8Hz
390	 */
391	period = loops_per_sec >> 3;
392	period /= (freq >> 3);
393
394	/* Derive pulse and space from the period */
395	pulse_width = period * duty_cycle / 100;
396	space_width = period - pulse_width;
397	dprintk("in init_timing_params, freq=%d, duty_cycle=%d, "
398		"clk/jiffy=%ld, pulse=%ld, space=%ld, "
399		"conv_us_to_clocks=%ld\n",
400		freq, duty_cycle, __this_cpu_read(cpu_info.loops_per_jiffy),
401		pulse_width, space_width, conv_us_to_clocks);
402	return 0;
403}
404#else /* ! USE_RDTSC */
405static int init_timing_params(unsigned int new_duty_cycle,
406		unsigned int new_freq)
407{
408/*
409 * period, pulse/space width are kept with 8 binary places -
410 * IE multiplied by 256.
411 */
412	if (256 * 1000000L / new_freq * new_duty_cycle / 100 <=
413	    LIRC_SERIAL_TRANSMITTER_LATENCY)
414		return -EINVAL;
415	if (256 * 1000000L / new_freq * (100 - new_duty_cycle) / 100 <=
416	    LIRC_SERIAL_TRANSMITTER_LATENCY)
417		return -EINVAL;
418	duty_cycle = new_duty_cycle;
419	freq = new_freq;
420	period = 256 * 1000000L / freq;
421	pulse_width = period * duty_cycle / 100;
422	space_width = period - pulse_width;
423	dprintk("in init_timing_params, freq=%d pulse=%ld, "
424		"space=%ld\n", freq, pulse_width, space_width);
425	return 0;
426}
427#endif /* USE_RDTSC */
428
429
430/* return value: space length delta */
431
432static long send_pulse_irdeo(unsigned long length)
433{
434	long rawbits, ret;
435	int i;
436	unsigned char output;
437	unsigned char chunk, shifted;
438
439	/* how many bits have to be sent ? */
440	rawbits = length * 1152 / 10000;
441	if (duty_cycle > 50)
442		chunk = 3;
443	else
444		chunk = 1;
445	for (i = 0, output = 0x7f; rawbits > 0; rawbits -= 3) {
446		shifted = chunk << (i * 3);
447		shifted >>= 1;
448		output &= (~shifted);
449		i++;
450		if (i == 3) {
451			soutp(UART_TX, output);
452			while (!(sinp(UART_LSR) & UART_LSR_THRE))
453				;
454			output = 0x7f;
455			i = 0;
456		}
457	}
458	if (i != 0) {
459		soutp(UART_TX, output);
460		while (!(sinp(UART_LSR) & UART_LSR_TEMT))
461			;
462	}
463
464	if (i == 0)
465		ret = (-rawbits) * 10000 / 1152;
466	else
467		ret = (3 - i) * 3 * 10000 / 1152 + (-rawbits) * 10000 / 1152;
468
469	return ret;
470}
471
472#ifdef USE_RDTSC
473/* Version that uses Pentium rdtsc instruction to measure clocks */
474
475/*
476 * This version does sub-microsecond timing using rdtsc instruction,
477 * and does away with the fudged LIRC_SERIAL_TRANSMITTER_LATENCY
478 * Implicitly i586 architecture...  - Steve
479 */
480
481static long send_pulse_homebrew_softcarrier(unsigned long length)
482{
483	int flag;
484	unsigned long target, start, now;
485
486	/* Get going quick as we can */
487	rdtscl(start);
488	on();
489	/* Convert length from microseconds to clocks */
490	length *= conv_us_to_clocks;
491	/* And loop till time is up - flipping at right intervals */
492	now = start;
493	target = pulse_width;
494	flag = 1;
495	/*
496	 * FIXME: This looks like a hard busy wait, without even an occasional,
497	 * polite, cpu_relax() call.  There's got to be a better way?
498	 *
499	 * The i2c code has the result of a lot of bit-banging work, I wonder if
500	 * there's something there which could be helpful here.
501	 */
502	while ((now - start) < length) {
503		/* Delay till flip time */
504		do {
505			rdtscl(now);
506		} while ((now - start) < target);
507
508		/* flip */
509		if (flag) {
510			rdtscl(now);
511			off();
512			target += space_width;
513		} else {
514			rdtscl(now); on();
515			target += pulse_width;
516		}
517		flag = !flag;
518	}
519	rdtscl(now);
520	return ((now - start) - length) / conv_us_to_clocks;
521}
522#else /* ! USE_RDTSC */
523/* Version using udelay() */
524
525/*
526 * here we use fixed point arithmetic, with 8
527 * fractional bits.  that gets us within 0.1% or so of the right average
528 * frequency, albeit with some jitter in pulse length - Steve
529 */
530
531/* To match 8 fractional bits used for pulse/space length */
532
533static long send_pulse_homebrew_softcarrier(unsigned long length)
534{
535	int flag;
536	unsigned long actual, target, d;
537	length <<= 8;
538
539	actual = 0; target = 0; flag = 0;
540	while (actual < length) {
541		if (flag) {
542			off();
543			target += space_width;
544		} else {
545			on();
546			target += pulse_width;
547		}
548		d = (target - actual -
549		     LIRC_SERIAL_TRANSMITTER_LATENCY + 128) >> 8;
550		/*
551		 * Note - we've checked in ioctl that the pulse/space
552		 * widths are big enough so that d is > 0
553		 */
554		udelay(d);
555		actual += (d << 8) + LIRC_SERIAL_TRANSMITTER_LATENCY;
556		flag = !flag;
557	}
558	return (actual-length) >> 8;
559}
560#endif /* USE_RDTSC */
561
562static long send_pulse_homebrew(unsigned long length)
563{
564	if (length <= 0)
565		return 0;
566
567	if (softcarrier)
568		return send_pulse_homebrew_softcarrier(length);
569	else {
570		on();
571		safe_udelay(length);
572		return 0;
573	}
574}
575
576static void send_space_irdeo(long length)
577{
578	if (length <= 0)
579		return;
580
581	safe_udelay(length);
582}
583
584static void send_space_homebrew(long length)
585{
586	off();
587	if (length <= 0)
588		return;
589	safe_udelay(length);
590}
591
592static void rbwrite(int l)
593{
594	if (lirc_buffer_full(&rbuf)) {
595		/* no new signals will be accepted */
596		dprintk("Buffer overrun\n");
597		return;
598	}
599	lirc_buffer_write(&rbuf, (void *)&l);
600}
601
602static void frbwrite(int l)
603{
604	/* simple noise filter */
605	static int pulse, space;
606	static unsigned int ptr;
607
608	if (ptr > 0 && (l & PULSE_BIT)) {
609		pulse += l & PULSE_MASK;
610		if (pulse > 250) {
611			rbwrite(space);
612			rbwrite(pulse | PULSE_BIT);
613			ptr = 0;
614			pulse = 0;
615		}
616		return;
617	}
618	if (!(l & PULSE_BIT)) {
619		if (ptr == 0) {
620			if (l > 20000) {
621				space = l;
622				ptr++;
623				return;
624			}
625		} else {
626			if (l > 20000) {
627				space += pulse;
628				if (space > PULSE_MASK)
629					space = PULSE_MASK;
630				space += l;
631				if (space > PULSE_MASK)
632					space = PULSE_MASK;
633				pulse = 0;
634				return;
635			}
636			rbwrite(space);
637			rbwrite(pulse | PULSE_BIT);
638			ptr = 0;
639			pulse = 0;
640		}
641	}
642	rbwrite(l);
643}
644
645static irqreturn_t irq_handler(int i, void *blah)
646{
647	struct timeval tv;
648	int counter, dcd;
649	u8 status;
650	long deltv;
651	int data;
652	static int last_dcd = -1;
653
654	if ((sinp(UART_IIR) & UART_IIR_NO_INT)) {
655		/* not our interrupt */
656		return IRQ_NONE;
657	}
658
659	counter = 0;
660	do {
661		counter++;
662		status = sinp(UART_MSR);
663		if (counter > RS_ISR_PASS_LIMIT) {
664			printk(KERN_WARNING LIRC_DRIVER_NAME ": AIEEEE: "
665			       "We're caught!\n");
666			break;
667		}
668		if ((status & hardware[type].signal_pin_change)
669		    && sense != -1) {
670			/* get current time */
671			do_gettimeofday(&tv);
672
673			/* New mode, written by Trent Piepho
674			   <xyzzy@u.washington.edu>. */
675
676			/*
677			 * The old format was not very portable.
678			 * We now use an int to pass pulses
679			 * and spaces to user space.
680			 *
681			 * If PULSE_BIT is set a pulse has been
682			 * received, otherwise a space has been
683			 * received.  The driver needs to know if your
684			 * receiver is active high or active low, or
685			 * the space/pulse sense could be
686			 * inverted. The bits denoted by PULSE_MASK are
687			 * the length in microseconds. Lengths greater
688			 * than or equal to 16 seconds are clamped to
689			 * PULSE_MASK.  All other bits are unused.
690			 * This is a much simpler interface for user
691			 * programs, as well as eliminating "out of
692			 * phase" errors with space/pulse
693			 * autodetection.
694			 */
695
696			/* calc time since last interrupt in microseconds */
697			dcd = (status & hardware[type].signal_pin) ? 1 : 0;
698
699			if (dcd == last_dcd) {
700				printk(KERN_WARNING LIRC_DRIVER_NAME
701				": ignoring spike: %d %d %lx %lx %lx %lx\n",
702				dcd, sense,
703				tv.tv_sec, lasttv.tv_sec,
704				tv.tv_usec, lasttv.tv_usec);
705				continue;
706			}
707
708			deltv = tv.tv_sec-lasttv.tv_sec;
709			if (tv.tv_sec < lasttv.tv_sec ||
710			    (tv.tv_sec == lasttv.tv_sec &&
711			     tv.tv_usec < lasttv.tv_usec)) {
712				printk(KERN_WARNING LIRC_DRIVER_NAME
713				       ": AIEEEE: your clock just jumped "
714				       "backwards\n");
715				printk(KERN_WARNING LIRC_DRIVER_NAME
716				       ": %d %d %lx %lx %lx %lx\n",
717				       dcd, sense,
718				       tv.tv_sec, lasttv.tv_sec,
719				       tv.tv_usec, lasttv.tv_usec);
720				data = PULSE_MASK;
721			} else if (deltv > 15) {
722				data = PULSE_MASK; /* really long time */
723				if (!(dcd^sense)) {
724					/* sanity check */
725					printk(KERN_WARNING LIRC_DRIVER_NAME
726					       ": AIEEEE: "
727					       "%d %d %lx %lx %lx %lx\n",
728					       dcd, sense,
729					       tv.tv_sec, lasttv.tv_sec,
730					       tv.tv_usec, lasttv.tv_usec);
731					/*
732					 * detecting pulse while this
733					 * MUST be a space!
734					 */
735					sense = sense ? 0 : 1;
736				}
737			} else
738				data = (int) (deltv*1000000 +
739					       tv.tv_usec -
740					       lasttv.tv_usec);
741			frbwrite(dcd^sense ? data : (data|PULSE_BIT));
742			lasttv = tv;
743			last_dcd = dcd;
744			wake_up_interruptible(&rbuf.wait_poll);
745		}
746	} while (!(sinp(UART_IIR) & UART_IIR_NO_INT)); /* still pending ? */
747	return IRQ_HANDLED;
748}
749
750
751static int hardware_init_port(void)
752{
753	u8 scratch, scratch2, scratch3;
754
755	/*
756	 * This is a simple port existence test, borrowed from the autoconfig
757	 * function in drivers/serial/8250.c
758	 */
759	scratch = sinp(UART_IER);
760	soutp(UART_IER, 0);
761#ifdef __i386__
762	outb(0xff, 0x080);
763#endif
764	scratch2 = sinp(UART_IER) & 0x0f;
765	soutp(UART_IER, 0x0f);
766#ifdef __i386__
767	outb(0x00, 0x080);
768#endif
769	scratch3 = sinp(UART_IER) & 0x0f;
770	soutp(UART_IER, scratch);
771	if (scratch2 != 0 || scratch3 != 0x0f) {
772		/* we fail, there's nothing here */
773		printk(KERN_ERR LIRC_DRIVER_NAME ": port existence test "
774		       "failed, cannot continue\n");
775		return -ENODEV;
776	}
777
778
779
780	/* Set DLAB 0. */
781	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
782
783	/* First of all, disable all interrupts */
784	soutp(UART_IER, sinp(UART_IER) &
785	      (~(UART_IER_MSI|UART_IER_RLSI|UART_IER_THRI|UART_IER_RDI)));
786
787	/* Clear registers. */
788	sinp(UART_LSR);
789	sinp(UART_RX);
790	sinp(UART_IIR);
791	sinp(UART_MSR);
792
793#ifdef CONFIG_LIRC_SERIAL_NSLU2
794	if (type == LIRC_NSLU2) {
795		/* Setup NSLU2 UART */
796
797		/* Enable UART */
798		soutp(UART_IER, sinp(UART_IER) | UART_IE_IXP42X_UUE);
799		/* Disable Receiver data Time out interrupt */
800		soutp(UART_IER, sinp(UART_IER) & ~UART_IE_IXP42X_RTOIE);
801		/* set out2 = interrupt unmask; off() doesn't set MCR
802		   on NSLU2 */
803		soutp(UART_MCR, UART_MCR_RTS|UART_MCR_OUT2);
804	}
805#endif
806
807	/* Set line for power source */
808	off();
809
810	/* Clear registers again to be sure. */
811	sinp(UART_LSR);
812	sinp(UART_RX);
813	sinp(UART_IIR);
814	sinp(UART_MSR);
815
816	switch (type) {
817	case LIRC_IRDEO:
818	case LIRC_IRDEO_REMOTE:
819		/* setup port to 7N1 @ 115200 Baud */
820		/* 7N1+start = 9 bits at 115200 ~ 3 bits at 38kHz */
821
822		/* Set DLAB 1. */
823		soutp(UART_LCR, sinp(UART_LCR) | UART_LCR_DLAB);
824		/* Set divisor to 1 => 115200 Baud */
825		soutp(UART_DLM, 0);
826		soutp(UART_DLL, 1);
827		/* Set DLAB 0 +  7N1 */
828		soutp(UART_LCR, UART_LCR_WLEN7);
829		/* THR interrupt already disabled at this point */
830		break;
831	default:
832		break;
833	}
834
835	return 0;
836}
837
838static int __devinit lirc_serial_probe(struct platform_device *dev)
839{
840	int i, nlow, nhigh, result;
841
842	result = request_irq(irq, irq_handler,
843			     (share_irq ? IRQF_SHARED : 0),
844			     LIRC_DRIVER_NAME, (void *)&hardware);
845	if (result < 0) {
846		if (result == -EBUSY)
847			printk(KERN_ERR LIRC_DRIVER_NAME ": IRQ %d busy\n",
848			       irq);
849		else if (result == -EINVAL)
850			printk(KERN_ERR LIRC_DRIVER_NAME
851			       ": Bad irq number or handler\n");
852		return result;
853	}
854
855	/* Reserve io region. */
856	/*
857	 * Future MMAP-Developers: Attention!
858	 * For memory mapped I/O you *might* need to use ioremap() first,
859	 * for the NSLU2 it's done in boot code.
860	 */
861	if (((iommap != 0)
862	     && (request_mem_region(iommap, 8 << ioshift,
863				    LIRC_DRIVER_NAME) == NULL))
864	   || ((iommap == 0)
865	       && (request_region(io, 8, LIRC_DRIVER_NAME) == NULL))) {
866		printk(KERN_ERR  LIRC_DRIVER_NAME
867		       ": port %04x already in use\n", io);
868		printk(KERN_WARNING LIRC_DRIVER_NAME
869		       ": use 'setserial /dev/ttySX uart none'\n");
870		printk(KERN_WARNING LIRC_DRIVER_NAME
871		       ": or compile the serial port driver as module and\n");
872		printk(KERN_WARNING LIRC_DRIVER_NAME
873		       ": make sure this module is loaded first\n");
874		result = -EBUSY;
875		goto exit_free_irq;
876	}
877
878	result = hardware_init_port();
879	if (result < 0)
880		goto exit_release_region;
881
882	/* Initialize pulse/space widths */
883	init_timing_params(duty_cycle, freq);
884
885	/* If pin is high, then this must be an active low receiver. */
886	if (sense == -1) {
887		/* wait 1/2 sec for the power supply */
888		msleep(500);
889
890		/*
891		 * probe 9 times every 0.04s, collect "votes" for
892		 * active high/low
893		 */
894		nlow = 0;
895		nhigh = 0;
896		for (i = 0; i < 9; i++) {
897			if (sinp(UART_MSR) & hardware[type].signal_pin)
898				nlow++;
899			else
900				nhigh++;
901			msleep(40);
902		}
903		sense = (nlow >= nhigh ? 1 : 0);
904		printk(KERN_INFO LIRC_DRIVER_NAME  ": auto-detected active "
905		       "%s receiver\n", sense ? "low" : "high");
906	} else
907		printk(KERN_INFO LIRC_DRIVER_NAME  ": Manually using active "
908		       "%s receiver\n", sense ? "low" : "high");
909
910	dprintk("Interrupt %d, port %04x obtained\n", irq, io);
911	return 0;
912
913exit_release_region:
914	if (iommap != 0)
915		release_mem_region(iommap, 8 << ioshift);
916	else
917		release_region(io, 8);
918exit_free_irq:
919	free_irq(irq, (void *)&hardware);
920
921	return result;
922}
923
924static int __devexit lirc_serial_remove(struct platform_device *dev)
925{
926	free_irq(irq, (void *)&hardware);
927
928	if (iommap != 0)
929		release_mem_region(iommap, 8 << ioshift);
930	else
931		release_region(io, 8);
932
933	return 0;
934}
935
936static int set_use_inc(void *data)
937{
938	unsigned long flags;
939
940	/* initialize timestamp */
941	do_gettimeofday(&lasttv);
942
943	spin_lock_irqsave(&hardware[type].lock, flags);
944
945	/* Set DLAB 0. */
946	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
947
948	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
949
950	spin_unlock_irqrestore(&hardware[type].lock, flags);
951
952	return 0;
953}
954
955static void set_use_dec(void *data)
956{	unsigned long flags;
957
958	spin_lock_irqsave(&hardware[type].lock, flags);
959
960	/* Set DLAB 0. */
961	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
962
963	/* First of all, disable all interrupts */
964	soutp(UART_IER, sinp(UART_IER) &
965	      (~(UART_IER_MSI|UART_IER_RLSI|UART_IER_THRI|UART_IER_RDI)));
966	spin_unlock_irqrestore(&hardware[type].lock, flags);
967}
968
969static ssize_t lirc_write(struct file *file, const char *buf,
970			 size_t n, loff_t *ppos)
971{
972	int i, count;
973	unsigned long flags;
974	long delta = 0;
975	int *wbuf;
976
977	if (!(hardware[type].features & LIRC_CAN_SEND_PULSE))
978		return -EPERM;
979
980	count = n / sizeof(int);
981	if (n % sizeof(int) || count % 2 == 0)
982		return -EINVAL;
983	wbuf = memdup_user(buf, n);
984	if (IS_ERR(wbuf))
985		return PTR_ERR(wbuf);
986	spin_lock_irqsave(&hardware[type].lock, flags);
987	if (type == LIRC_IRDEO) {
988		/* DTR, RTS down */
989		on();
990	}
991	for (i = 0; i < count; i++) {
992		if (i%2)
993			hardware[type].send_space(wbuf[i] - delta);
994		else
995			delta = hardware[type].send_pulse(wbuf[i]);
996	}
997	off();
998	spin_unlock_irqrestore(&hardware[type].lock, flags);
999	kfree(wbuf);
1000	return n;
1001}
1002
1003static long lirc_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
1004{
1005	int result;
1006	__u32 value;
1007
1008	switch (cmd) {
1009	case LIRC_GET_SEND_MODE:
1010		if (!(hardware[type].features&LIRC_CAN_SEND_MASK))
1011			return -ENOIOCTLCMD;
1012
1013		result = put_user(LIRC_SEND2MODE
1014				  (hardware[type].features&LIRC_CAN_SEND_MASK),
1015				  (__u32 *) arg);
1016		if (result)
1017			return result;
1018		break;
1019
1020	case LIRC_SET_SEND_MODE:
1021		if (!(hardware[type].features&LIRC_CAN_SEND_MASK))
1022			return -ENOIOCTLCMD;
1023
1024		result = get_user(value, (__u32 *) arg);
1025		if (result)
1026			return result;
1027		/* only LIRC_MODE_PULSE supported */
1028		if (value != LIRC_MODE_PULSE)
1029			return -EINVAL;
1030		break;
1031
1032	case LIRC_GET_LENGTH:
1033		return -ENOIOCTLCMD;
1034		break;
1035
1036	case LIRC_SET_SEND_DUTY_CYCLE:
1037		dprintk("SET_SEND_DUTY_CYCLE\n");
1038		if (!(hardware[type].features&LIRC_CAN_SET_SEND_DUTY_CYCLE))
1039			return -ENOIOCTLCMD;
1040
1041		result = get_user(value, (__u32 *) arg);
1042		if (result)
1043			return result;
1044		if (value <= 0 || value > 100)
1045			return -EINVAL;
1046		return init_timing_params(value, freq);
1047		break;
1048
1049	case LIRC_SET_SEND_CARRIER:
1050		dprintk("SET_SEND_CARRIER\n");
1051		if (!(hardware[type].features&LIRC_CAN_SET_SEND_CARRIER))
1052			return -ENOIOCTLCMD;
1053
1054		result = get_user(value, (__u32 *) arg);
1055		if (result)
1056			return result;
1057		if (value > 500000 || value < 20000)
1058			return -EINVAL;
1059		return init_timing_params(duty_cycle, value);
1060		break;
1061
1062	default:
1063		return lirc_dev_fop_ioctl(filep, cmd, arg);
1064	}
1065	return 0;
1066}
1067
1068static const struct file_operations lirc_fops = {
1069	.owner		= THIS_MODULE,
1070	.write		= lirc_write,
1071	.unlocked_ioctl	= lirc_ioctl,
1072#ifdef CONFIG_COMPAT
1073	.compat_ioctl	= lirc_ioctl,
1074#endif
1075	.read		= lirc_dev_fop_read,
1076	.poll		= lirc_dev_fop_poll,
1077	.open		= lirc_dev_fop_open,
1078	.release	= lirc_dev_fop_close,
1079	.llseek		= no_llseek,
1080};
1081
1082static struct lirc_driver driver = {
1083	.name		= LIRC_DRIVER_NAME,
1084	.minor		= -1,
1085	.code_length	= 1,
1086	.sample_rate	= 0,
1087	.data		= NULL,
1088	.add_to_buf	= NULL,
1089	.rbuf		= &rbuf,
1090	.set_use_inc	= set_use_inc,
1091	.set_use_dec	= set_use_dec,
1092	.fops		= &lirc_fops,
1093	.dev		= NULL,
1094	.owner		= THIS_MODULE,
1095};
1096
1097static struct platform_device *lirc_serial_dev;
1098
1099static int lirc_serial_suspend(struct platform_device *dev,
1100			       pm_message_t state)
1101{
1102	/* Set DLAB 0. */
1103	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
1104
1105	/* Disable all interrupts */
1106	soutp(UART_IER, sinp(UART_IER) &
1107	      (~(UART_IER_MSI|UART_IER_RLSI|UART_IER_THRI|UART_IER_RDI)));
1108
1109	/* Clear registers. */
1110	sinp(UART_LSR);
1111	sinp(UART_RX);
1112	sinp(UART_IIR);
1113	sinp(UART_MSR);
1114
1115	return 0;
1116}
1117
1118/* twisty maze... need a forward-declaration here... */
1119static void lirc_serial_exit(void);
1120
1121static int lirc_serial_resume(struct platform_device *dev)
1122{
1123	unsigned long flags;
1124	int result;
1125
1126	result = hardware_init_port();
1127	if (result < 0)
1128		return result;
1129
1130	spin_lock_irqsave(&hardware[type].lock, flags);
1131	/* Enable Interrupt */
1132	do_gettimeofday(&lasttv);
1133	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
1134	off();
1135
1136	lirc_buffer_clear(&rbuf);
1137
1138	spin_unlock_irqrestore(&hardware[type].lock, flags);
1139
1140	return 0;
1141}
1142
1143static struct platform_driver lirc_serial_driver = {
1144	.probe		= lirc_serial_probe,
1145	.remove		= __devexit_p(lirc_serial_remove),
1146	.suspend	= lirc_serial_suspend,
1147	.resume		= lirc_serial_resume,
1148	.driver		= {
1149		.name	= "lirc_serial",
1150		.owner	= THIS_MODULE,
1151	},
1152};
1153
1154static int __init lirc_serial_init(void)
1155{
1156	int result;
1157
1158	/* Init read buffer. */
1159	result = lirc_buffer_init(&rbuf, sizeof(int), RBUF_LEN);
1160	if (result < 0)
1161		return result;
1162
1163	result = platform_driver_register(&lirc_serial_driver);
1164	if (result) {
1165		printk("lirc register returned %d\n", result);
1166		goto exit_buffer_free;
1167	}
1168
1169	lirc_serial_dev = platform_device_alloc("lirc_serial", 0);
1170	if (!lirc_serial_dev) {
1171		result = -ENOMEM;
1172		goto exit_driver_unregister;
1173	}
1174
1175	result = platform_device_add(lirc_serial_dev);
1176	if (result)
1177		goto exit_device_put;
1178
1179	return 0;
1180
1181exit_device_put:
1182	platform_device_put(lirc_serial_dev);
1183exit_driver_unregister:
1184	platform_driver_unregister(&lirc_serial_driver);
1185exit_buffer_free:
1186	lirc_buffer_free(&rbuf);
1187	return result;
1188}
1189
1190static void lirc_serial_exit(void)
1191{
1192	platform_device_unregister(lirc_serial_dev);
1193	platform_driver_unregister(&lirc_serial_driver);
1194	lirc_buffer_free(&rbuf);
1195}
1196
1197static int __init lirc_serial_init_module(void)
1198{
1199	int result;
1200
1201	switch (type) {
1202	case LIRC_HOMEBREW:
1203	case LIRC_IRDEO:
1204	case LIRC_IRDEO_REMOTE:
1205	case LIRC_ANIMAX:
1206	case LIRC_IGOR:
1207		/* if nothing specified, use ttyS0/com1 and irq 4 */
1208		io = io ? io : 0x3f8;
1209		irq = irq ? irq : 4;
1210		break;
1211#ifdef CONFIG_LIRC_SERIAL_NSLU2
1212	case LIRC_NSLU2:
1213		io = io ? io : IRQ_IXP4XX_UART2;
1214		irq = irq ? irq : (IXP4XX_UART2_BASE_VIRT + REG_OFFSET);
1215		iommap = iommap ? iommap : IXP4XX_UART2_BASE_PHYS;
1216		ioshift = ioshift ? ioshift : 2;
1217		break;
1218#endif
1219	default:
1220		return -EINVAL;
1221	}
1222	if (!softcarrier) {
1223		switch (type) {
1224		case LIRC_HOMEBREW:
1225		case LIRC_IGOR:
1226#ifdef CONFIG_LIRC_SERIAL_NSLU2
1227		case LIRC_NSLU2:
1228#endif
1229			hardware[type].features &=
1230				~(LIRC_CAN_SET_SEND_DUTY_CYCLE|
1231				  LIRC_CAN_SET_SEND_CARRIER);
1232			break;
1233		}
1234	}
1235
1236	result = lirc_serial_init();
1237	if (result)
1238		return result;
1239
1240	driver.features = hardware[type].features;
1241	driver.dev = &lirc_serial_dev->dev;
1242	driver.minor = lirc_register_driver(&driver);
1243	if (driver.minor < 0) {
1244		printk(KERN_ERR  LIRC_DRIVER_NAME
1245		       ": register_chrdev failed!\n");
1246		lirc_serial_exit();
1247		return driver.minor;
1248	}
1249	return 0;
1250}
1251
1252static void __exit lirc_serial_exit_module(void)
1253{
1254	lirc_unregister_driver(driver.minor);
1255	lirc_serial_exit();
1256	dprintk("cleaned up module\n");
1257}
1258
1259
1260module_init(lirc_serial_init_module);
1261module_exit(lirc_serial_exit_module);
1262
1263MODULE_DESCRIPTION("Infra-red receiver driver for serial ports.");
1264MODULE_AUTHOR("Ralph Metzler, Trent Piepho, Ben Pfaff, "
1265	      "Christoph Bartelmus, Andrei Tanas");
1266MODULE_LICENSE("GPL");
1267
1268module_param(type, int, S_IRUGO);
1269MODULE_PARM_DESC(type, "Hardware type (0 = home-brew, 1 = IRdeo,"
1270		 " 2 = IRdeo Remote, 3 = AnimaX, 4 = IgorPlug,"
1271		 " 5 = NSLU2 RX:CTS2/TX:GreenLED)");
1272
1273module_param(io, int, S_IRUGO);
1274MODULE_PARM_DESC(io, "I/O address base (0x3f8 or 0x2f8)");
1275
1276/* some architectures (e.g. intel xscale) have memory mapped registers */
1277module_param(iommap, bool, S_IRUGO);
1278MODULE_PARM_DESC(iommap, "physical base for memory mapped I/O"
1279		" (0 = no memory mapped io)");
1280
1281/*
1282 * some architectures (e.g. intel xscale) align the 8bit serial registers
1283 * on 32bit word boundaries.
1284 * See linux-kernel/drivers/tty/serial/8250/8250.c serial_in()/out()
1285 */
1286module_param(ioshift, int, S_IRUGO);
1287MODULE_PARM_DESC(ioshift, "shift I/O register offset (0 = no shift)");
1288
1289module_param(irq, int, S_IRUGO);
1290MODULE_PARM_DESC(irq, "Interrupt (4 or 3)");
1291
1292module_param(share_irq, bool, S_IRUGO);
1293MODULE_PARM_DESC(share_irq, "Share interrupts (0 = off, 1 = on)");
1294
1295module_param(sense, bool, S_IRUGO);
1296MODULE_PARM_DESC(sense, "Override autodetection of IR receiver circuit"
1297		 " (0 = active high, 1 = active low )");
1298
1299#ifdef CONFIG_LIRC_SERIAL_TRANSMITTER
1300module_param(txsense, bool, S_IRUGO);
1301MODULE_PARM_DESC(txsense, "Sense of transmitter circuit"
1302		 " (0 = active high, 1 = active low )");
1303#endif
1304
1305module_param(softcarrier, bool, S_IRUGO);
1306MODULE_PARM_DESC(softcarrier, "Software carrier (0 = off, 1 = on, default on)");
1307
1308module_param(debug, bool, S_IRUGO | S_IWUSR);
1309MODULE_PARM_DESC(debug, "Enable debugging messages");
1310