[PATCH 02/18] lirc serial port receiver/transmitter device driver

[Jarod Wilson <jwilson@redhat.com>]

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Janne Grunau <j@jannau.net>
CC: Christoph Bartelmus <lirc@bartelmus.de>
---
 drivers/input/lirc/Kconfig       |    7 +
 drivers/input/lirc/Makefile      |    1 +
 drivers/input/lirc/lirc_serial.c | 1312 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 1320 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/lirc/lirc_serial.c

diff --git a/drivers/input/lirc/Kconfig b/drivers/input/lirc/Kconfig
index 2a04d9b..73403b9 100644
--- a/drivers/input/lirc/Kconfig
+++ b/drivers/input/lirc/Kconfig
@@ -18,4 +18,11 @@ config LIRC_DEV
 	help
 	  LIRC device loadable module support, required for most LIRC drivers
 
+config LIRC_SERIAL
+	tristate "Homebrew Serial Port Receiver"
+	default n
+	depends on LIRC_DEV
+	help
+	  Driver for Homebrew Serial Port Receivers
+
 endif
diff --git a/drivers/input/lirc/Makefile b/drivers/input/lirc/Makefile
index cdb4c45..7d76128 100644
--- a/drivers/input/lirc/Makefile
+++ b/drivers/input/lirc/Makefile
@@ -6,3 +6,4 @@
 EXTRA_CFLAGS =-DIRCTL_DEV_MAJOR=61 -DLIRC_SERIAL_TRANSMITTER -I$(src)
 
 obj-$(CONFIG_LIRC_DEV)		+= lirc_dev.o
+obj-$(CONFIG_LIRC_SERIAL)	+= lirc_serial.o
diff --git a/drivers/input/lirc/lirc_serial.c b/drivers/input/lirc/lirc_serial.c
new file mode 100644
index 0000000..465edd9
--- /dev/null
+++ b/drivers/input/lirc/lirc_serial.c
@@ -0,0 +1,1312 @@
+/****************************************************************************
+ ** lirc_serial.c ***********************************************************
+ ****************************************************************************
+ *
+ * lirc_serial - Device driver that records pulse- and pause-lengths
+ *	       (space-lengths) between DDCD event on a serial port.
+ *
+ * Copyright (C) 1996,97 Ralph Metzler <rjkm@thp.uni-koeln.de>
+ * Copyright (C) 1998 Trent Piepho <xyzzy@u.washington.edu>
+ * Copyright (C) 1998 Ben Pfaff <blp@gnu.org>
+ * Copyright (C) 1999 Christoph Bartelmus <lirc@bartelmus.de>
+ * Copyright (C) 2007 Andrei Tanas <andrei@tanas.ca> (suspend/resume support)
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+/* Steve's changes to improve transmission fidelity:
+     - for systems with the rdtsc instruction and the clock counter, a
+       send_pule that times the pulses directly using the counter.
+       This means that the LIRC_SERIAL_TRANSMITTER_LATENCY fudge is
+       not needed. Measurement shows very stable waveform, even where
+       PCI activity slows the access to the UART, which trips up other
+       versions.
+     - For other system, non-integer-microsecond pulse/space lengths,
+       done using fixed point binary. So, much more accurate carrier
+       frequency.
+     - fine tuned transmitter latency, taking advantage of fractional
+       microseconds in previous change
+     - Fixed bug in the way transmitter latency was accounted for by
+       tuning the pulse lengths down - the send_pulse routine ignored
+       this overhead as it timed the overall pulse length - so the
+       pulse frequency was right but overall pulse length was too
+       long. Fixed by accounting for latency on each pulse/space
+       iteration.
+
+   Steve Davies <steve@daviesfam.org>  July 2001
+*/
+
+#include <linux/version.h>
+
+#include <linux/autoconf.h>
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/serial_reg.h>
+#include <linux/time.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/poll.h>
+#include <linux/platform_device.h>
+
+#include <asm/system.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/fcntl.h>
+
+#if defined(LIRC_SERIAL_NSLU2)
+#include <asm/hardware.h>
+/* From Intel IXP42X Developer's Manual (#252480-005): */
+/* ftp://download.intel.com/design/network/manuals/25248005.pdf */
+#define UART_IE_IXP42X_UUE   0x40 /* IXP42X UART Unit enable */
+#define UART_IE_IXP42X_RTOIE 0x10 /* IXP42X Receiver Data Timeout int.enable */
+#ifndef NSLU2_LED_GRN_GPIO
+/* added in 2.6.22 */
+#define NSLU2_LED_GRN_GPIO NSLU2_LED_GRN
+#endif
+#endif
+
+#include "lirc.h"
+#include "lirc_dev.h"
+
+#define LIRC_DRIVER_NAME "lirc_serial"
+
+struct lirc_serial {
+	int signal_pin;
+	int signal_pin_change;
+	int on;
+	int off;
+	long (*send_pulse)(unsigned long length);
+	void (*send_space)(long length);
+	int features;
+};
+
+#define LIRC_HOMEBREW	0
+#define LIRC_IRDEO	   1
+#define LIRC_IRDEO_REMOTE    2
+#define LIRC_ANIMAX	  3
+#define LIRC_IGOR	    4
+#define LIRC_NSLU2	   5
+
+#ifdef LIRC_SERIAL_IRDEO
+static int type = LIRC_IRDEO;
+#elif defined(LIRC_SERIAL_IRDEO_REMOTE)
+static int type = LIRC_IRDEO_REMOTE;
+#elif defined(LIRC_SERIAL_ANIMAX)
+static int type = LIRC_ANIMAX;
+#elif defined(LIRC_SERIAL_IGOR)
+static int type = LIRC_IGOR;
+#elif defined(LIRC_SERIAL_NSLU2)
+static int type = LIRC_NSLU2;
+#else
+static int type = LIRC_HOMEBREW;
+#endif
+
+/* Set defaults for NSLU2 */
+#if defined(LIRC_SERIAL_NSLU2)
+#ifndef LIRC_IRQ
+#define LIRC_IRQ IRQ_IXP4XX_UART2
+#endif
+#ifndef LIRC_PORT
+#define LIRC_PORT (IXP4XX_UART2_BASE_VIRT + REG_OFFSET)
+#endif
+#ifndef LIRC_IOMMAP
+#define LIRC_IOMMAP IXP4XX_UART2_BASE_PHYS
+#endif
+#ifndef LIRC_IOSHIFT
+#define LIRC_IOSHIFT 2
+#endif
+#ifndef LIRC_ALLOW_MMAPPED_IO
+#define LIRC_ALLOW_MMAPPED_IO
+#endif
+#endif
+
+#if defined(LIRC_ALLOW_MMAPPED_IO)
+#ifndef LIRC_IOMMAP
+#define LIRC_IOMMAP 0
+#endif
+#ifndef LIRC_IOSHIFT
+#define LIRC_IOSHIFT 0
+#endif
+static int iommap = LIRC_IOMMAP;
+static int ioshift = LIRC_IOSHIFT;
+#endif
+
+#ifdef LIRC_SERIAL_SOFTCARRIER
+static int softcarrier = 1;
+#else
+static int softcarrier;
+#endif
+
+static int share_irq;
+static int debug;
+
+#define dprintk(fmt, args...)					\
+	do {							\
+		if (debug)					\
+			printk(KERN_DEBUG LIRC_DRIVER_NAME ": "	\
+			       fmt, ## args);			\
+	} while (0)
+
+/* forward declarations */
+static long send_pulse_irdeo(unsigned long length);
+static long send_pulse_homebrew(unsigned long length);
+static void send_space_irdeo(long length);
+static void send_space_homebrew(long length);
+
+static struct lirc_serial hardware[] = {
+	/* home-brew receiver/transmitter */
+	{
+		UART_MSR_DCD,
+		UART_MSR_DDCD,
+		UART_MCR_RTS|UART_MCR_OUT2|UART_MCR_DTR,
+		UART_MCR_RTS|UART_MCR_OUT2,
+		send_pulse_homebrew,
+		send_space_homebrew,
+		(
+#ifdef LIRC_SERIAL_TRANSMITTER
+		 LIRC_CAN_SET_SEND_DUTY_CYCLE|
+		 LIRC_CAN_SET_SEND_CARRIER|
+		 LIRC_CAN_SEND_PULSE|
+#endif
+		 LIRC_CAN_REC_MODE2)
+	},
+
+	/* IRdeo classic */
+	{
+		UART_MSR_DSR,
+		UART_MSR_DDSR,
+		UART_MCR_OUT2,
+		UART_MCR_RTS|UART_MCR_DTR|UART_MCR_OUT2,
+		send_pulse_irdeo,
+		send_space_irdeo,
+		(LIRC_CAN_SET_SEND_DUTY_CYCLE|
+		 LIRC_CAN_SEND_PULSE|
+		 LIRC_CAN_REC_MODE2)
+	},
+
+	/* IRdeo remote */
+	{
+		UART_MSR_DSR,
+		UART_MSR_DDSR,
+		UART_MCR_RTS|UART_MCR_DTR|UART_MCR_OUT2,
+		UART_MCR_RTS|UART_MCR_DTR|UART_MCR_OUT2,
+		send_pulse_irdeo,
+		send_space_irdeo,
+		(LIRC_CAN_SET_SEND_DUTY_CYCLE|
+		 LIRC_CAN_SEND_PULSE|
+		 LIRC_CAN_REC_MODE2)
+	},
+
+	/* AnimaX */
+	{
+		UART_MSR_DCD,
+		UART_MSR_DDCD,
+		0,
+		UART_MCR_RTS|UART_MCR_DTR|UART_MCR_OUT2,
+		NULL,
+		NULL,
+		LIRC_CAN_REC_MODE2
+	},
+
+	/* home-brew receiver/transmitter (Igor Cesko's variation) */
+	{
+		UART_MSR_DSR,
+		UART_MSR_DDSR,
+		UART_MCR_RTS|UART_MCR_OUT2|UART_MCR_DTR,
+		UART_MCR_RTS|UART_MCR_OUT2,
+		send_pulse_homebrew,
+		send_space_homebrew,
+		(
+#ifdef LIRC_SERIAL_TRANSMITTER
+		 LIRC_CAN_SET_SEND_DUTY_CYCLE|
+		 LIRC_CAN_SET_SEND_CARRIER|
+		 LIRC_CAN_SEND_PULSE|
+#endif
+		 LIRC_CAN_REC_MODE2)
+	},
+
+#if defined(LIRC_SERIAL_NSLU2)
+	/* Modified Linksys Network Storage Link USB 2.0 (NSLU2):
+	   We receive on CTS of the 2nd serial port (R142,LHS), we
+	   transmit with a IR diode between GPIO[1] (green status LED),
+	   and ground (Matthias Goebl <matthias.goebl@goebl.net>).
+	   See also http://www.nslu2-linux.org for this device */
+	{
+		UART_MSR_CTS,
+		UART_MSR_DCTS,
+		UART_MCR_RTS|UART_MCR_OUT2|UART_MCR_DTR,
+		UART_MCR_RTS|UART_MCR_OUT2,
+		send_pulse_homebrew,
+		send_space_homebrew,
+		(
+#ifdef LIRC_SERIAL_TRANSMITTER
+		 LIRC_CAN_SET_SEND_DUTY_CYCLE|
+		 LIRC_CAN_SET_SEND_CARRIER|
+		 LIRC_CAN_SEND_PULSE|
+#endif
+		 LIRC_CAN_REC_MODE2)
+	},
+#endif
+
+};
+
+#define RS_ISR_PASS_LIMIT 256
+
+/* A long pulse code from a remote might take upto 300 bytes.  The
+   daemon should read the bytes as soon as they are generated, so take
+   the number of keys you think you can push before the daemon runs
+   and multiply by 300.  The driver will warn you if you overrun this
+   buffer.  If you have a slow computer or non-busmastering IDE disks,
+   maybe you will need to increase this.  */
+
+/* This MUST be a power of two!  It has to be larger than 1 as well. */
+
+#define RBUF_LEN 256
+#define WBUF_LEN 256
+
+static int sense = -1;	/* -1 = auto, 0 = active high, 1 = active low */
+static int txsense;     /* 0 = active high, 1 = active low */
+
+#ifndef LIRC_IRQ
+#define LIRC_IRQ 4
+#endif
+#ifndef LIRC_PORT
+#define LIRC_PORT 0x3f8
+#endif
+
+static int io = LIRC_PORT;
+static int irq = LIRC_IRQ;
+
+static struct timeval lasttv = {0, 0};
+
+static struct lirc_buffer rbuf;
+
+static int wbuf[WBUF_LEN];
+
+static unsigned int freq = 38000;
+static unsigned int duty_cycle = 50;
+
+/* Initialized in init_timing_params() */
+static unsigned long period;
+static unsigned long pulse_width;
+static unsigned long space_width;
+
+#if defined(__i386__)
+/*
+  From:
+  Linux I/O port programming mini-HOWTO
+  Author: Riku Saikkonen <Riku.Saikkonen@hut.fi>
+  v, 28 December 1997
+
+  [...]
+  Actually, a port I/O instruction on most ports in the 0-0x3ff range
+  takes almost exactly 1 microsecond, so if you're, for example, using
+  the parallel port directly, just do additional inb()s from that port
+  to delay.
+  [...]
+*/
+/* transmitter latency 1.5625us 0x1.90 - this figure arrived at from
+ * comment above plus trimming to match actual measured frequency.
+ * This will be sensitive to cpu speed, though hopefully most of the 1.5us
+ * is spent in the uart access.  Still - for reference test machine was a
+ * 1.13GHz Athlon system - Steve
+ */
+
+/* changed from 400 to 450 as this works better on slower machines;
+   faster machines will use the rdtsc code anyway */
+
+#define LIRC_SERIAL_TRANSMITTER_LATENCY 450
+
+#else
+
+/* does anybody have information on other platforms ? */
+/* 256 = 1<<8 */
+#define LIRC_SERIAL_TRANSMITTER_LATENCY 256
+
+#endif  /* __i386__ */
+
+static inline unsigned int sinp(int offset)
+{
+#if defined(LIRC_ALLOW_MMAPPED_IO)
+	if (iommap != 0) {
+		/* the register is memory-mapped */
+		offset <<= ioshift;
+		return readb(io + offset);
+	}
+#endif
+	return inb(io + offset);
+}
+
+static inline void soutp(int offset, int value)
+{
+#if defined(LIRC_ALLOW_MMAPPED_IO)
+	if (iommap != 0) {
+		/* the register is memory-mapped */
+		offset <<= ioshift;
+		writeb(value, io + offset);
+	}
+#endif
+	outb(value, io + offset);
+}
+
+static inline void on(void)
+{
+#if defined(LIRC_SERIAL_NSLU2)
+	/* On NSLU2, we put the transmit diode between the output of the green
+	   status LED and ground */
+	if (type == LIRC_NSLU2) {
+		gpio_line_set(NSLU2_LED_GRN_GPIO, IXP4XX_GPIO_LOW);
+		return;
+	}
+#endif
+	if (txsense)
+		soutp(UART_MCR, hardware[type].off);
+	else
+		soutp(UART_MCR, hardware[type].on);
+}
+
+static inline void off(void)
+{
+#if defined(LIRC_SERIAL_NSLU2)
+	if (type == LIRC_NSLU2) {
+		gpio_line_set(NSLU2_LED_GRN_GPIO, IXP4XX_GPIO_HIGH);
+		return;
+	}
+#endif
+	if (txsense)
+		soutp(UART_MCR, hardware[type].on);
+	else
+		soutp(UART_MCR, hardware[type].off);
+}
+
+#ifndef MAX_UDELAY_MS
+#define MAX_UDELAY_US 5000
+#else
+#define MAX_UDELAY_US (MAX_UDELAY_MS*1000)
+#endif
+
+static inline void safe_udelay(unsigned long usecs)
+{
+	while (usecs > MAX_UDELAY_US) {
+		udelay(MAX_UDELAY_US);
+		usecs -= MAX_UDELAY_US;
+	}
+	udelay(usecs);
+}
+
+#ifdef USE_RDTSC
+/* This is an overflow/precision juggle, complicated in that we can't
+   do long long divide in the kernel */
+
+/* When we use the rdtsc instruction to measure clocks, we keep the
+ * pulse and space widths as clock cycles.  As this is CPU speed
+ * dependent, the widths must be calculated in init_port and ioctl
+ * time
+ */
+
+/* So send_pulse can quickly convert microseconds to clocks */
+static unsigned long conv_us_to_clocks;
+
+static inline int init_timing_params(unsigned int new_duty_cycle,
+		unsigned int new_freq)
+{
+	unsigned long long loops_per_sec, work;
+
+	duty_cycle = new_duty_cycle;
+	freq = new_freq;
+
+	loops_per_sec = current_cpu_data.loops_per_jiffy;
+	loops_per_sec *= HZ;
+
+	/* How many clocks in a microsecond?, avoiding long long divide */
+	work = loops_per_sec;
+	work *= 4295;  /* 4295 = 2^32 / 1e6 */
+	conv_us_to_clocks = (work>>32);
+
+	/* Carrier period in clocks, approach good up to 32GHz clock,
+	   gets carrier frequency within 8Hz */
+	period = loops_per_sec>>3;
+	period /= (freq>>3);
+
+	/* Derive pulse and space from the period */
+
+	pulse_width = period*duty_cycle/100;
+	space_width = period - pulse_width;
+	dprintk("in init_timing_params, freq=%d, duty_cycle=%d, "
+		"clk/jiffy=%ld, pulse=%ld, space=%ld, "
+		"conv_us_to_clocks=%ld\n",
+		freq, duty_cycle, current_cpu_data.loops_per_jiffy,
+		pulse_width, space_width, conv_us_to_clocks);
+	return 0;
+}
+#else /* ! USE_RDTSC */
+static inline int init_timing_params(unsigned int new_duty_cycle,
+		unsigned int new_freq)
+{
+/* period, pulse/space width are kept with 8 binary places -
+ * IE multiplied by 256. */
+	if (256*1000000L/new_freq*new_duty_cycle/100 <=
+	    LIRC_SERIAL_TRANSMITTER_LATENCY)
+		return -EINVAL;
+	if (256*1000000L/new_freq*(100-new_duty_cycle)/100 <=
+	    LIRC_SERIAL_TRANSMITTER_LATENCY)
+		return -EINVAL;
+	duty_cycle = new_duty_cycle;
+	freq = new_freq;
+	period = 256*1000000L/freq;
+	pulse_width = period*duty_cycle/100;
+	space_width = period-pulse_width;
+	dprintk("in init_timing_params, freq=%d pulse=%ld, "
+		"space=%ld\n", freq, pulse_width, space_width);
+	return 0;
+}
+#endif /* USE_RDTSC */
+
+
+/* return value: space length delta */
+
+static long send_pulse_irdeo(unsigned long length)
+{
+	long rawbits;
+	int i;
+	unsigned char output;
+	unsigned char chunk, shifted;
+
+	/* how many bits have to be sent ? */
+	rawbits = length*1152/10000;
+	if (duty_cycle > 50)
+		chunk = 3;
+	else
+		chunk = 1;
+	for (i = 0, output = 0x7f; rawbits > 0; rawbits -= 3) {
+		shifted = chunk<<(i*3);
+		shifted >>= 1;
+		output &= (~shifted);
+		i++;
+		if (i == 3) {
+			soutp(UART_TX, output);
+			while (!(sinp(UART_LSR) & UART_LSR_THRE))
+				;
+			output = 0x7f;
+			i = 0;
+		}
+	}
+	if (i != 0) {
+		soutp(UART_TX, output);
+		while (!(sinp(UART_LSR) & UART_LSR_TEMT))
+			;
+	}
+
+	if (i == 0)
+		return (-rawbits)*10000/1152;
+	else
+		return (3-i)*3*10000/1152 + (-rawbits)*10000/1152;
+}
+
+#ifdef USE_RDTSC
+/* Version that uses Pentium rdtsc instruction to measure clocks */
+
+/* This version does sub-microsecond timing using rdtsc instruction,
+ * and does away with the fudged LIRC_SERIAL_TRANSMITTER_LATENCY
+ * Implicitly i586 architecture...  - Steve
+ */
+
+static inline long send_pulse_homebrew_softcarrier(unsigned long length)
+{
+	int flag;
+	unsigned long target, start, now;
+
+	/* Get going quick as we can */
+	rdtscl(start); on();
+	/* Convert length from microseconds to clocks */
+	length *= conv_us_to_clocks;
+	/* And loop till time is up - flipping at right intervals */
+	now = start;
+	target = pulse_width;
+	flag = 1;
+	while ((now-start) < length) {
+		/* Delay till flip time */
+		do {
+			rdtscl(now);
+		} while ((now-start) < target);
+
+		/* flip */
+		if (flag) {
+			rdtscl(now); off();
+			target += space_width;
+		} else {
+			rdtscl(now); on();
+			target += pulse_width;
+		}
+		flag = !flag;
+	}
+	rdtscl(now);
+	return ((now-start)-length) / conv_us_to_clocks;
+}
+#else /* ! USE_RDTSC */
+/* Version using udelay() */
+
+/* here we use fixed point arithmetic, with 8
+   fractional bits.  that gets us within 0.1% or so of the right average
+   frequency, albeit with some jitter in pulse length - Steve */
+
+/* To match 8 fractional bits used for pulse/space length */
+
+static inline long send_pulse_homebrew_softcarrier(unsigned long length)
+{
+	int flag;
+	unsigned long actual, target, d;
+	length <<= 8;
+
+	actual = 0; target = 0; flag = 0;
+	while (actual < length) {
+		if (flag) {
+			off();
+			target += space_width;
+		} else {
+			on();
+			target += pulse_width;
+		}
+		d = (target-actual-LIRC_SERIAL_TRANSMITTER_LATENCY+128)>>8;
+		/* Note - we've checked in ioctl that the pulse/space
+		   widths are big enough so that d is > 0 */
+		udelay(d);
+		actual += (d<<8)+LIRC_SERIAL_TRANSMITTER_LATENCY;
+		flag = !flag;
+	}
+	return (actual-length)>>8;
+}
+#endif /* USE_RDTSC */
+
+static long send_pulse_homebrew(unsigned long length)
+{
+	if (length <= 0)
+		return 0;
+
+	if (softcarrier)
+		return send_pulse_homebrew_softcarrier(length);
+	else {
+		on();
+		safe_udelay(length);
+		return 0;
+	}
+}
+
+static void send_space_irdeo(long length)
+{
+	if (length <= 0)
+		return;
+
+	safe_udelay(length);
+}
+
+static void send_space_homebrew(long length)
+{
+	off();
+	if (length <= 0)
+		return;
+	safe_udelay(length);
+}
+
+static inline void rbwrite(int l)
+{
+	if (lirc_buffer_full(&rbuf)) {
+		/* no new signals will be accepted */
+		dprintk("Buffer overrun\n");
+		return;
+	}
+	_lirc_buffer_write_1(&rbuf, (void *)&l);
+}
+
+static inline void frbwrite(int l)
+{
+	/* simple noise filter */
+	static int pulse, space;
+	static unsigned int ptr;
+
+	if (ptr > 0 && (l & PULSE_BIT)) {
+		pulse += l & PULSE_MASK;
+		if (pulse > 250) {
+			rbwrite(space);
+			rbwrite(pulse | PULSE_BIT);
+			ptr = 0;
+			pulse = 0;
+		}
+		return;
+	}
+	if (!(l & PULSE_BIT)) {
+		if (ptr == 0) {
+			if (l > 20000) {
+				space = l;
+				ptr++;
+				return;
+			}
+		} else {
+			if (l > 20000) {
+				space += pulse;
+				if (space > PULSE_MASK)
+					space = PULSE_MASK;
+				space += l;
+				if (space > PULSE_MASK)
+					space = PULSE_MASK;
+				pulse = 0;
+				return;
+			}
+			rbwrite(space);
+			rbwrite(pulse | PULSE_BIT);
+			ptr = 0;
+			pulse = 0;
+		}
+	}
+	rbwrite(l);
+}
+
+static irqreturn_t irq_handler(int i, void *blah)
+{
+	struct timeval tv;
+	int status, counter, dcd;
+	long deltv;
+	int data;
+	static int last_dcd = -1;
+
+	if ((sinp(UART_IIR) & UART_IIR_NO_INT)) {
+		/* not our interrupt */
+		return IRQ_RETVAL(IRQ_NONE);
+	}
+
+	counter = 0;
+	do {
+		counter++;
+		status = sinp(UART_MSR);
+		if (counter > RS_ISR_PASS_LIMIT) {
+			printk(KERN_WARNING LIRC_DRIVER_NAME ": AIEEEE: "
+			       "We're caught!\n");
+			break;
+		}
+		if ((status&hardware[type].signal_pin_change) && sense != -1) {
+			/* get current time */
+			do_gettimeofday(&tv);
+
+			/* New mode, written by Trent Piepho
+			   <xyzzy@u.washington.edu>. */
+
+			/* The old format was not very portable.
+			   We now use an int to pass pulses
+			   and spaces to user space.
+
+			   If PULSE_BIT is set a pulse has been
+			   received, otherwise a space has been
+			   received.  The driver needs to know if your
+			   receiver is active high or active low, or
+			   the space/pulse sense could be
+			   inverted. The bits denoted by PULSE_MASK are
+			   the length in microseconds. Lengths greater
+			   than or equal to 16 seconds are clamped to
+			   PULSE_MASK.  All other bits are unused.
+			   This is a much simpler interface for user
+			   programs, as well as eliminating "out of
+			   phase" errors with space/pulse
+			   autodetection. */
+
+			/* calculate time since last interrupt in
+			   microseconds */
+			dcd = (status & hardware[type].signal_pin) ? 1 : 0;
+
+			if (dcd == last_dcd) {
+				printk(KERN_WARNING LIRC_DRIVER_NAME
+				": ignoring spike: %d %d %lx %lx %lx %lx\n",
+				dcd, sense,
+				tv.tv_sec, lasttv.tv_sec,
+				tv.tv_usec, lasttv.tv_usec);
+				continue;
+			}
+
+			deltv = tv.tv_sec-lasttv.tv_sec;
+			if (tv.tv_sec < lasttv.tv_sec ||
+			    (tv.tv_sec == lasttv.tv_sec &&
+			     tv.tv_usec < lasttv.tv_usec)) {
+				printk(KERN_WARNING LIRC_DRIVER_NAME
+				       ": AIEEEE: your clock just jumped "
+				       "backwards\n");
+				printk(KERN_WARNING LIRC_DRIVER_NAME
+				       ": %d %d %lx %lx %lx %lx\n",
+				       dcd, sense,
+				       tv.tv_sec, lasttv.tv_sec,
+				       tv.tv_usec, lasttv.tv_usec);
+				data = PULSE_MASK;
+			} else if (deltv > 15) {
+				data = PULSE_MASK; /* really long time */
+				if (!(dcd^sense)) {
+					/* sanity check */
+					printk(KERN_WARNING LIRC_DRIVER_NAME
+					       ": AIEEEE: "
+					       "%d %d %lx %lx %lx %lx\n",
+					       dcd, sense,
+					       tv.tv_sec, lasttv.tv_sec,
+					       tv.tv_usec, lasttv.tv_usec);
+					/* detecting pulse while this
+					   MUST be a space! */
+					sense = sense ? 0 : 1;
+				}
+			} else
+				data = (int) (deltv*1000000 +
+					       tv.tv_usec -
+					       lasttv.tv_usec);
+			frbwrite(dcd^sense ? data : (data|PULSE_BIT));
+			lasttv = tv;
+			last_dcd = dcd;
+			wake_up_interruptible(&rbuf.wait_poll);
+		}
+	} while (!(sinp(UART_IIR) & UART_IIR_NO_INT)); /* still pending ? */
+	return IRQ_RETVAL(IRQ_HANDLED);
+}
+
+static void hardware_init_port(void)
+{
+	unsigned long flags;
+	local_irq_save(flags);
+
+	/* Set DLAB 0. */
+	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
+
+	/* First of all, disable all interrupts */
+	soutp(UART_IER, sinp(UART_IER) &
+	      (~(UART_IER_MSI|UART_IER_RLSI|UART_IER_THRI|UART_IER_RDI)));
+
+	/* Clear registers. */
+	sinp(UART_LSR);
+	sinp(UART_RX);
+	sinp(UART_IIR);
+	sinp(UART_MSR);
+
+#if defined(LIRC_SERIAL_NSLU2)
+	if (type == LIRC_NSLU2) {
+		/* Setup NSLU2 UART */
+
+		/* Enable UART */
+		soutp(UART_IER, sinp(UART_IER) | UART_IE_IXP42X_UUE);
+		/* Disable Receiver data Time out interrupt */
+		soutp(UART_IER, sinp(UART_IER) & ~UART_IE_IXP42X_RTOIE);
+		/* set out2 = interupt unmask; off() doesn't set MCR
+		   on NSLU2 */
+		soutp(UART_MCR, UART_MCR_RTS|UART_MCR_OUT2);
+	}
+#endif
+
+	/* Set line for power source */
+	off();
+
+	/* Clear registers again to be sure. */
+	sinp(UART_LSR);
+	sinp(UART_RX);
+	sinp(UART_IIR);
+	sinp(UART_MSR);
+
+	switch (type) {
+	case LIRC_IRDEO:
+	case LIRC_IRDEO_REMOTE:
+		/* setup port to 7N1 @ 115200 Baud */
+		/* 7N1+start = 9 bits at 115200 ~ 3 bits at 38kHz */
+
+		/* Set DLAB 1. */
+		soutp(UART_LCR, sinp(UART_LCR) | UART_LCR_DLAB);
+		/* Set divisor to 1 => 115200 Baud */
+		soutp(UART_DLM, 0);
+		soutp(UART_DLL, 1);
+		/* Set DLAB 0 +  7N1 */
+		soutp(UART_LCR, UART_LCR_WLEN7);
+		/* THR interrupt already disabled at this point */
+		break;
+	default:
+		break;
+	}
+
+	local_irq_restore(flags);
+}
+
+static int init_port(void)
+{
+	int i, nlow, nhigh;
+
+	/* Reserve io region. */
+#if defined(LIRC_ALLOW_MMAPPED_IO)
+	/* Future MMAP-Developers: Attention!
+	   For memory mapped I/O you *might* need to use ioremap() first,
+	   for the NSLU2 it's done in boot code. */
+	if (((iommap != 0)
+	     && (request_mem_region(iommap, 8<<ioshift,
+				    LIRC_DRIVER_NAME) == NULL))
+	   || ((iommap == 0)
+	       && (request_region(io, 8, LIRC_DRIVER_NAME) == NULL))) {
+#else
+	if (request_region(io, 8, LIRC_DRIVER_NAME) == NULL) {
+#endif
+		printk(KERN_ERR  LIRC_DRIVER_NAME
+		       ": port %04x already in use\n", io);
+		printk(KERN_WARNING LIRC_DRIVER_NAME
+		       ": use 'setserial /dev/ttySX uart none'\n");
+		printk(KERN_WARNING LIRC_DRIVER_NAME
+		       ": or compile the serial port driver as module and\n");
+		printk(KERN_WARNING LIRC_DRIVER_NAME
+		       ": make sure this module is loaded first\n");
+		return -EBUSY;
+	}
+
+	hardware_init_port();
+
+	/* Initialize pulse/space widths */
+	init_timing_params(duty_cycle, freq);
+
+	/* If pin is high, then this must be an active low receiver. */
+	if (sense == -1) {
+		/* wait 1/2 sec for the power supply */
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		schedule_timeout(HZ/2);
+
+		/* probe 9 times every 0.04s, collect "votes" for
+		   active high/low */
+		nlow = 0;
+		nhigh = 0;
+		for (i = 0; i < 9; i++) {
+			if (sinp(UART_MSR) & hardware[type].signal_pin)
+				nlow++;
+			else
+				nhigh++;
+			schedule_timeout(HZ/25);
+		}
+		sense = (nlow >= nhigh ? 1 : 0);
+		printk(KERN_INFO  LIRC_DRIVER_NAME  ": auto-detected active "
+		       "%s receiver\n", sense ? "low" : "high");
+	} else
+		printk(KERN_INFO  LIRC_DRIVER_NAME  ": Manually using active "
+		       "%s receiver\n", sense ? "low" : "high");
+
+	return 0;
+}
+
+static int set_use_inc(void *data)
+{
+	int result;
+	unsigned long flags;
+
+	/* Init read buffer. */
+	if (lirc_buffer_init(&rbuf, sizeof(int), RBUF_LEN) < 0)
+		return -ENOMEM;
+
+	/* initialize timestamp */
+	do_gettimeofday(&lasttv);
+
+	result = request_irq(irq, irq_handler,
+			   IRQF_DISABLED | (share_irq ? IRQF_SHARED : 0),
+			   LIRC_DRIVER_NAME, (void *)&hardware);
+
+	switch (result) {
+	case -EBUSY:
+		printk(KERN_ERR LIRC_DRIVER_NAME ": IRQ %d busy\n", irq);
+		lirc_buffer_free(&rbuf);
+		return -EBUSY;
+	case -EINVAL:
+		printk(KERN_ERR LIRC_DRIVER_NAME
+		       ": Bad irq number or handler\n");
+		lirc_buffer_free(&rbuf);
+		return -EINVAL;
+	default:
+		dprintk("Interrupt %d, port %04x obtained\n", irq, io);
+		break;
+	};
+
+	local_irq_save(flags);
+
+	/* Set DLAB 0. */
+	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
+
+	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
+
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+static void set_use_dec(void *data)
+{	unsigned long flags;
+
+	local_irq_save(flags);
+
+	/* Set DLAB 0. */
+	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
+
+	/* First of all, disable all interrupts */
+	soutp(UART_IER, sinp(UART_IER) &
+	      (~(UART_IER_MSI|UART_IER_RLSI|UART_IER_THRI|UART_IER_RDI)));
+	local_irq_restore(flags);
+
+	free_irq(irq, (void *)&hardware);
+
+	dprintk("freed IRQ %d\n", irq);
+	lirc_buffer_free(&rbuf);
+}
+
+static ssize_t lirc_write(struct file *file, const char *buf,
+			 size_t n, loff_t *ppos)
+{
+	int i, count;
+	unsigned long flags;
+	long delta = 0;
+
+	if (!(hardware[type].features&LIRC_CAN_SEND_PULSE))
+		return -EBADF;
+
+	if (n % sizeof(int))
+		return -EINVAL;
+	count = n / sizeof(int);
+	if (count > WBUF_LEN || count % 2 == 0)
+		return -EINVAL;
+	if (copy_from_user(wbuf, buf, n))
+		return -EFAULT;
+	local_irq_save(flags);
+	if (type == LIRC_IRDEO) {
+		/* DTR, RTS down */
+		on();
+	}
+	for (i = 0; i < count; i++) {
+		if (i%2)
+			hardware[type].send_space(wbuf[i]-delta);
+		else
+			delta = hardware[type].send_pulse(wbuf[i]);
+	}
+	off();
+	local_irq_restore(flags);
+	return n;
+}
+
+static int lirc_ioctl(struct inode *node, struct file *filep, unsigned int cmd,
+		      unsigned long arg)
+{
+	int result;
+	unsigned long value;
+	unsigned int ivalue;
+
+	switch (cmd) {
+	case LIRC_GET_SEND_MODE:
+		if (!(hardware[type].features&LIRC_CAN_SEND_MASK))
+			return -ENOIOCTLCMD;
+
+		result = put_user(LIRC_SEND2MODE
+				  (hardware[type].features&LIRC_CAN_SEND_MASK),
+				  (unsigned long *) arg);
+		if (result)
+			return result;
+		break;
+
+	case LIRC_SET_SEND_MODE:
+		if (!(hardware[type].features&LIRC_CAN_SEND_MASK))
+			return -ENOIOCTLCMD;
+
+		result = get_user(value, (unsigned long *) arg);
+		if (result)
+			return result;
+		/* only LIRC_MODE_PULSE supported */
+		if (value != LIRC_MODE_PULSE)
+			return -ENOSYS;
+		break;
+
+	case LIRC_GET_LENGTH:
+		return -ENOSYS;
+		break;
+
+	case LIRC_SET_SEND_DUTY_CYCLE:
+		dprintk("SET_SEND_DUTY_CYCLE\n");
+		if (!(hardware[type].features&LIRC_CAN_SET_SEND_DUTY_CYCLE))
+			return -ENOIOCTLCMD;
+
+		result = get_user(ivalue, (unsigned int *) arg);
+		if (result)
+			return result;
+		if (ivalue <= 0 || ivalue > 100)
+			return -EINVAL;
+		return init_timing_params(ivalue, freq);
+		break;
+
+	case LIRC_SET_SEND_CARRIER:
+		dprintk("SET_SEND_CARRIER\n");
+		if (!(hardware[type].features&LIRC_CAN_SET_SEND_CARRIER))
+			return -ENOIOCTLCMD;
+
+		result = get_user(ivalue, (unsigned int *) arg);
+		if (result)
+			return result;
+		if (ivalue > 500000 || ivalue < 20000)
+			return -EINVAL;
+		return init_timing_params(duty_cycle, ivalue);
+		break;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static struct file_operations lirc_fops = {
+	.write	= lirc_write,
+};
+
+static struct lirc_plugin plugin = {
+	.name		= LIRC_DRIVER_NAME,
+	.minor		= -1,
+	.code_length	= 1,
+	.sample_rate	= 0,
+	.data		= NULL,
+	.add_to_buf	= NULL,
+	.get_queue	= NULL,
+	.rbuf		= &rbuf,
+	.set_use_inc	= set_use_inc,
+	.set_use_dec	= set_use_dec,
+	.ioctl		= lirc_ioctl,
+	.fops		= &lirc_fops,
+	.dev		= NULL,
+	.owner		= THIS_MODULE,
+};
+
+#ifdef MODULE
+
+static struct platform_device *lirc_serial_dev;
+
+static int __devinit lirc_serial_probe(struct platform_device *dev)
+{
+	return 0;
+}
+
+static int __devexit lirc_serial_remove(struct platform_device *dev)
+{
+	return 0;
+}
+
+static int lirc_serial_suspend(struct platform_device *dev,
+			       pm_message_t state)
+{
+	/* Set DLAB 0. */
+	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
+
+	/* Disable all interrupts */
+	soutp(UART_IER, sinp(UART_IER) &
+	      (~(UART_IER_MSI|UART_IER_RLSI|UART_IER_THRI|UART_IER_RDI)));
+
+	/* Clear registers. */
+	sinp(UART_LSR);
+	sinp(UART_RX);
+	sinp(UART_IIR);
+	sinp(UART_MSR);
+
+	return 0;
+}
+
+static int lirc_serial_resume(struct platform_device *dev)
+{
+	unsigned long flags;
+
+	hardware_init_port();
+
+	local_irq_save(flags);
+	/* Enable Interrupt */
+	do_gettimeofday(&lasttv);
+	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
+	off();
+
+	lirc_buffer_clear(&rbuf);
+
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+static struct platform_driver lirc_serial_driver = {
+	.probe		= lirc_serial_probe,
+	.remove		= __devexit_p(lirc_serial_remove),
+	.suspend	= lirc_serial_suspend,
+	.resume		= lirc_serial_resume,
+	.driver		= {
+		.name	= "lirc_serial",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init lirc_serial_init(void)
+{
+	int result;
+
+	result = platform_driver_register(&lirc_serial_driver);
+	if (result) {
+		printk("lirc register returned %d\n", result);
+		return result;
+	}
+
+	lirc_serial_dev = platform_device_alloc("lirc_serial", 0);
+	if (!lirc_serial_dev) {
+		result = -ENOMEM;
+		goto exit_driver_unregister;
+	}
+
+	result = platform_device_add(lirc_serial_dev);
+	if (result)
+		goto exit_device_put;
+
+	return 0;
+
+exit_device_put:
+	platform_device_put(lirc_serial_dev);
+exit_driver_unregister:
+	platform_driver_unregister(&lirc_serial_driver);
+	return result;
+}
+
+static void __exit lirc_serial_exit(void)
+{
+	platform_device_unregister(lirc_serial_dev);
+	platform_driver_unregister(&lirc_serial_driver);
+}
+
+int __init init_module(void)
+{
+	int result;
+
+	result = lirc_serial_init();
+	if (result)
+		return result;
+	switch (type) {
+	case LIRC_HOMEBREW:
+	case LIRC_IRDEO:
+	case LIRC_IRDEO_REMOTE:
+	case LIRC_ANIMAX:
+	case LIRC_IGOR:
+#if defined(LIRC_SERIAL_NSLU2)
+	case LIRC_NSLU2:
+#endif
+		break;
+	default:
+		result = -EINVAL;
+		goto exit_serial_exit;
+	}
+	if (!softcarrier) {
+		switch (type) {
+		case LIRC_HOMEBREW:
+		case LIRC_IGOR:
+		case LIRC_NSLU2:
+			hardware[type].features &=
+				~(LIRC_CAN_SET_SEND_DUTY_CYCLE|
+				  LIRC_CAN_SET_SEND_CARRIER);
+			break;
+		}
+	}
+	result = init_port();
+	if (result < 0)
+		goto exit_serial_exit;
+	plugin.features = hardware[type].features;
+	plugin.minor = lirc_register_plugin(&plugin);
+	if (plugin.minor < 0) {
+		printk(KERN_ERR  LIRC_DRIVER_NAME
+		       ": register_chrdev failed!\n");
+		result = -EIO;
+		goto exit_release;
+	}
+	return 0;
+exit_release:
+	release_region(io, 8);
+exit_serial_exit:
+	lirc_serial_exit();
+	return result;
+}
+
+void __exit cleanup_module(void)
+{
+	lirc_serial_exit();
+#if defined(LIRC_ALLOW_MMAPPED_IO)
+	if (iommap != 0)
+		release_mem_region(iommap, 8<<ioshift);
+	else
+		release_region(io, 8);
+#else
+	release_region(io, 8);
+#endif
+	lirc_unregister_plugin(plugin.minor);
+	dprintk("cleaned up module\n");
+}
+
+MODULE_DESCRIPTION("Infra-red receiver driver for serial ports.");
+MODULE_AUTHOR("Ralph Metzler, Trent Piepho, Ben Pfaff, "
+	      "Christoph Bartelmus, Andrei Tanas");
+MODULE_LICENSE("GPL");
+
+module_param(type, int, 0444);
+#if defined(LIRC_SERIAL_NSLU2)
+MODULE_PARM_DESC(type, "Hardware type (0 = home-brew, 1 = IRdeo,"
+		 " 2 = IRdeo Remote, 3 = AnimaX, 4 = IgorPlug,"
+		 " 5 = NSLU2 RX:CTS2/TX:GreenLED)");
+#else
+MODULE_PARM_DESC(type, "Hardware type (0 = home-brew, 1 = IRdeo,"
+		 " 2 = IRdeo Remote, 3 = AnimaX, 4 = IgorPlug)");
+#endif
+
+module_param(io, int, 0444);
+MODULE_PARM_DESC(io, "I/O address base (0x3f8 or 0x2f8)");
+
+#if defined(LIRC_ALLOW_MMAPPED_IO)
+/* some architectures (e.g. intel xscale) have memory mapped registers */
+module_param(iommap, bool, 0444);
+MODULE_PARM_DESC(iommap, "physical base for memory mapped I/O"
+		" (0 = no memory mapped io)");
+
+/* some architectures (e.g. intel xscale) align the 8bit serial registers
+   on 32bit word boundaries.
+   See linux-kernel/serial/8250.c serial_in()/out() */
+module_param(ioshift, int, 0444);
+MODULE_PARM_DESC(ioshift, "shift I/O register offset (0 = no shift)");
+#endif
+
+module_param(irq, int, 0444);
+MODULE_PARM_DESC(irq, "Interrupt (4 or 3)");
+
+module_param(share_irq, bool, 0444);
+MODULE_PARM_DESC(share_irq, "Share interrupts (0 = off, 1 = on)");
+
+module_param(sense, bool, 0444);
+MODULE_PARM_DESC(sense, "Override autodetection of IR receiver circuit"
+		 " (0 = active high, 1 = active low )");
+
+#ifdef LIRC_SERIAL_TRANSMITTER
+module_param(txsense, bool, 0444);
+MODULE_PARM_DESC(txsense, "Sense of transmitter circuit"
+		 " (0 = active high, 1 = active low )");
+#endif
+
+module_param(softcarrier, bool, 0444);
+MODULE_PARM_DESC(softcarrier, "Software carrier (0 = off, 1 = on)");
+
+module_param(debug, bool, 0644);
+MODULE_PARM_DESC(debug, "Enable debugging messages");
+
+#endif /* MODULE */
-- 
1.6.0.1