diff mbox

[1/2,media] serial_ir: port lirc_serial to rc-core

Message ID 1478108285-12046-1-git-send-email-sean@mess.org (mailing list archive)
State New, archived
Headers show

Commit Message

Sean Young Nov. 2, 2016, 5:38 p.m. UTC
Tested with a homebrew serial ir.

Signed-off-by: Sean Young <sean@mess.org>
---
 MAINTAINERS                  |    6 +
 drivers/media/rc/Kconfig     |   17 +
 drivers/media/rc/Makefile    |    1 +
 drivers/media/rc/serial_ir.c | 1020 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 1044 insertions(+)
 create mode 100644 drivers/media/rc/serial_ir.c

Comments

kernel test robot Nov. 2, 2016, 7:39 p.m. UTC | #1
Hi Sean,

[auto build test WARNING on linuxtv-media/master]
[also build test WARNING on v4.9-rc3 next-20161028]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
[Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
[Check https://git-scm.com/docs/git-format-patch for more information]

url:    https://github.com/0day-ci/linux/commits/Sean-Young/serial_ir-port-lirc_serial-to-rc-core/20161103-014155
base:   git://linuxtv.org/media_tree.git master
config: parisc-allyesconfig (attached as .config)
compiler: hppa-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=parisc 

All warnings (new ones prefixed by >>):

   drivers/media/rc/serial_ir.c: In function 'serial_ir_irq_handler':
>> drivers/media/rc/serial_ir.c:592:1: warning: the frame size of 1196 bytes is larger than 1024 bytes [-Wframe-larger-than=]
    }
    ^

vim +592 drivers/media/rc/serial_ir.c

   576							ktime_to_us(lastkt));
   577						/*
   578						 * detecting pulse while this
   579						 * MUST be a space!
   580						 */
   581						sense = sense ? 0 : 1;
   582					}
   583				} else
   584					data = (unsigned int)ktime_to_ns(delkt);
   585				frbwrite(data, !(dcd^sense));
   586				lastkt = kt;
   587				last_dcd = dcd;
   588				ir_raw_event_handle(rcdev);
   589			}
   590		} while (!(sinp(UART_IIR) & UART_IIR_NO_INT)); /* still pending ? */
   591		return IRQ_HANDLED;
 > 592	}
   593	
   594	
   595	static int hardware_init_port(void)
   596	{
   597		u8 scratch, scratch2, scratch3;
   598	
   599		/*
   600		 * This is a simple port existence test, borrowed from the autoconfig

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Sean Young Nov. 10, 2016, 2:24 p.m. UTC | #2
On Thu, Nov 03, 2016 at 03:39:31AM +0800, kbuild test robot wrote:
> Hi Sean,
> 
> [auto build test WARNING on linuxtv-media/master]
> [also build test WARNING on v4.9-rc3 next-20161028]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> [Suggest to use git(>=2.9.0) format-patch --base=<commit> (or --base=auto for convenience) to record what (public, well-known) commit your patch series was built on]
> [Check https://git-scm.com/docs/git-format-patch for more information]
> 
> url:    https://github.com/0day-ci/linux/commits/Sean-Young/serial_ir-port-lirc_serial-to-rc-core/20161103-014155
> base:   git://linuxtv.org/media_tree.git master
> config: parisc-allyesconfig (attached as .config)
> compiler: hppa-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
> reproduce:
>         wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         make.cross ARCH=parisc 
> 
> All warnings (new ones prefixed by >>):
> 
>    drivers/media/rc/serial_ir.c: In function 'serial_ir_irq_handler':
> >> drivers/media/rc/serial_ir.c:592:1: warning: the frame size of 1196 bytes is larger than 1024 bytes [-Wframe-larger-than=]

Since ktime_t is in nanoseconds, ktime_to_us() does a 64 bit division by 1000
which quite some instructions/stack space on 32 bit parisc. Since the 
ktime_to_us() is just for a printk() it can simply report in nanoseconds
(so use ktime_to_ns() instead). The resulting machine code on parisc 32 bit
is much shorter and the warning goes away.

I'll send out a new version of this patch shortly. Please ignore this
version.

Thanks,

Sean
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diff mbox

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 93e9f42..cd8fd50 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10604,6 +10604,12 @@  S:	Maintained
 F:	Documentation/devicetree/bindings/serial/
 F:	drivers/tty/serial/
 
+SERIAL IR RECEIVER
+M:	Sean Young <sean@mess.org>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+F:	drivers/media/rc/serial_ir.c
+
 STI CEC DRIVER
 M:	Benjamin Gaignard <benjamin.gaignard@linaro.org>
 L:	kernel@stlinux.com
diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
index 370e16e..629e8ca 100644
--- a/drivers/media/rc/Kconfig
+++ b/drivers/media/rc/Kconfig
@@ -389,4 +389,21 @@  config IR_SUNXI
 	   To compile this driver as a module, choose M here: the module will
 	   be called sunxi-ir.
 
+config IR_SERIAL
+	tristate "Homebrew Serial Port Receiver"
+	depends on RC_CORE
+	---help---
+	   Say Y if you want to use Homebrew Serial Port Receivers and
+	   Transceivers.
+
+	   To compile this driver as a module, choose M here: the module will
+	   be called serial-ir.
+
+config IR_SERIAL_TRANSMITTER
+	bool "Serial Port Transmitter"
+	default y
+	depends on IR_SERIAL
+	---help---
+	   Serial Port Transmitter support
+
 endif #RC_DEVICES
diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
index 379a5c0..3a984ee 100644
--- a/drivers/media/rc/Makefile
+++ b/drivers/media/rc/Makefile
@@ -37,3 +37,4 @@  obj-$(CONFIG_IR_TTUSBIR) += ttusbir.o
 obj-$(CONFIG_RC_ST) += st_rc.o
 obj-$(CONFIG_IR_SUNXI) += sunxi-cir.o
 obj-$(CONFIG_IR_IMG) += img-ir/
+obj-$(CONFIG_IR_SERIAL) += serial_ir.o
diff --git a/drivers/media/rc/serial_ir.c b/drivers/media/rc/serial_ir.c
new file mode 100644
index 0000000..77193c3
--- /dev/null
+++ b/drivers/media/rc/serial_ir.c
@@ -0,0 +1,1020 @@ 
+/*
+ * serial-ir.c
+ *
+ * serial-ir - 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)
+ * Copyright (C) 2016 Sean Young <sean@mess.org> (port to rc-core)
+ *  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.
+ */
+
+/*
+ * 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 IR_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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/serial_reg.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <media/rc-core.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 */
+
+#define DRIVER_NAME "serial_ir"
+
+struct serial_ir {
+	int signal_pin;
+	int signal_pin_change;
+	u8 on;
+	u8 off;
+	long (*send_pulse)(unsigned long length);
+	void (*send_space)(long length);
+	bool set_send_carrier;
+	bool set_duty_cycle;
+	spinlock_t lock;
+};
+
+#define IR_HOMEBREW	0
+#define IR_IRDEO	1
+#define IR_IRDEO_REMOTE	2
+#define IR_ANIMAX	3
+#define IR_IGOR		4
+#define IR_NSLU2	5
+
+/*** module parameters ***/
+static int type;
+static int io;
+static int irq;
+static bool iommap;
+static int ioshift;
+static bool softcarrier = true;
+static bool share_irq;
+static int sense = -1;	/* -1 = auto, 0 = active high, 1 = active low */
+static bool txsense;	/* 0 = active high, 1 = active low */
+
+/* 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 serial_ir hardware[] = {
+	[IR_HOMEBREW] = {
+		.lock = __SPIN_LOCK_UNLOCKED(hardware[IR_HOMEBREW].lock),
+		.signal_pin	   = UART_MSR_DCD,
+		.signal_pin_change = UART_MSR_DDCD,
+		.on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
+		.off = (UART_MCR_RTS | UART_MCR_OUT2),
+		.send_pulse = send_pulse_homebrew,
+		.send_space = send_space_homebrew,
+#ifdef CONFIG_IR_SERIAL_TRANSMITTER
+		.set_send_carrier = true,
+		.set_duty_cycle = true,
+#endif
+	},
+
+	[IR_IRDEO] = {
+		.lock = __SPIN_LOCK_UNLOCKED(hardware[IR_IRDEO].lock),
+		.signal_pin	   = UART_MSR_DSR,
+		.signal_pin_change = UART_MSR_DDSR,
+		.on  = UART_MCR_OUT2,
+		.off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
+		.send_pulse  = send_pulse_irdeo,
+		.send_space  = send_space_irdeo,
+		.set_duty_cycle = true,
+	},
+
+	[IR_IRDEO_REMOTE] = {
+		.lock = __SPIN_LOCK_UNLOCKED(hardware[IR_IRDEO_REMOTE].lock),
+		.signal_pin	   = UART_MSR_DSR,
+		.signal_pin_change = UART_MSR_DDSR,
+		.on  = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
+		.off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
+		.send_pulse  = send_pulse_irdeo,
+		.send_space  = send_space_irdeo,
+		.set_duty_cycle = true,
+	},
+
+	[IR_ANIMAX] = {
+		.lock = __SPIN_LOCK_UNLOCKED(hardware[IR_ANIMAX].lock),
+		.signal_pin	   = UART_MSR_DCD,
+		.signal_pin_change = UART_MSR_DDCD,
+		.on  = 0,
+		.off = (UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2),
+		.send_pulse = NULL,
+		.send_space = NULL,
+	},
+
+	[IR_IGOR] = {
+		.lock = __SPIN_LOCK_UNLOCKED(hardware[IR_IGOR].lock),
+		.signal_pin	   = UART_MSR_DSR,
+		.signal_pin_change = UART_MSR_DDSR,
+		.on  = (UART_MCR_RTS | UART_MCR_OUT2 | UART_MCR_DTR),
+		.off = (UART_MCR_RTS | UART_MCR_OUT2),
+		.send_pulse = send_pulse_homebrew,
+		.send_space = send_space_homebrew,
+#ifdef CONFIG_IR_SERIAL_TRANSMITTER
+		.set_send_carrier = true,
+		.set_duty_cycle = true,
+#endif
+	},
+};
+
+#define RS_ISR_PASS_LIMIT 256
+
+/*
+ * A long pulse code from a remote might take up to 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. */
+
+static ktime_t lastkt;
+
+static struct rc_dev *rcdev;
+
+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 IR_SERIAL_TRANSMITTER_LATENCY 450
+
+#else
+
+/* does anybody have information on other platforms ? */
+/* 256 = 1<<8 */
+#define IR_SERIAL_TRANSMITTER_LATENCY 256
+
+#endif	/* __i386__ */
+/*
+ * FIXME: should we be using hrtimers instead of this
+ * IR_SERIAL_TRANSMITTER_LATENCY nonsense?
+ */
+
+/* fetch serial input packet (1 byte) from register offset */
+static u8 sinp(int offset)
+{
+	if (iommap)
+		/* the register is memory-mapped */
+		offset <<= ioshift;
+
+	return inb(io + offset);
+}
+
+/* write serial output packet (1 byte) of value to register offset */
+static void soutp(int offset, u8 value)
+{
+	if (iommap)
+		/* the register is memory-mapped */
+		offset <<= ioshift;
+
+	outb(value, io + offset);
+}
+
+static void on(void)
+{
+	if (txsense)
+		soutp(UART_MCR, hardware[type].off);
+	else
+		soutp(UART_MCR, hardware[type].on);
+}
+
+static void off(void)
+{
+	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 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
+ */
+
+static int init_timing_params(unsigned int new_duty_cycle,
+		unsigned int new_freq)
+{
+	__u64 loops_per_sec, work;
+
+	duty_cycle = new_duty_cycle;
+	freq = new_freq;
+
+	loops_per_sec = __this_cpu_read(cpu.info.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 */
+
+	/*
+	 * 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;
+	pr_debug("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, __this_cpu_read(cpu_info.loops_per_jiffy),
+		 pulse_width, space_width, conv_us_to_clocks);
+	return 0;
+}
+#else /* ! USE_RDTSC */
+static 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 <=
+	    IR_SERIAL_TRANSMITTER_LATENCY)
+		return -EINVAL;
+	if (256 * 1000000L / new_freq * (100 - new_duty_cycle) / 100 <=
+	    IR_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;
+	pr_debug("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, ret;
+	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)
+		ret = (-rawbits) * 10000 / 1152;
+	else
+		ret = (3 - i) * 3 * 10000 / 1152 + (-rawbits) * 10000 / 1152;
+
+	return ret;
+}
+
+/* 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
+ *
+ * This should use ndelay instead.
+ */
+
+/* To match 8 fractional bits used for pulse/space length */
+
+static 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 -
+		     IR_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) + IR_SERIAL_TRANSMITTER_LATENCY;
+		flag = !flag;
+	}
+	return (actual-length) >> 8;
+}
+
+static long send_pulse_homebrew(unsigned long length)
+{
+	if (length <= 0)
+		return 0;
+
+	if (softcarrier)
+		return send_pulse_homebrew_softcarrier(length);
+
+	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 void frbwrite(unsigned int l, bool is_pulse)
+{
+	/* simple noise filter */
+	static unsigned int ptr, pulse, space;
+	DEFINE_IR_RAW_EVENT(ev);
+
+	if (ptr > 0 && is_pulse) {
+		pulse += l;
+		if (pulse > 250000) {
+			ev.duration = space;
+			ev.pulse = false;
+			ir_raw_event_store_with_filter(rcdev, &ev);
+			ev.duration = pulse;
+			ev.pulse = true;
+			ir_raw_event_store_with_filter(rcdev, &ev);
+			ptr = 0;
+			pulse = 0;
+		}
+		return;
+	}
+	if (!is_pulse) {
+		if (ptr == 0) {
+			if (l > 20000000) {
+				space = l;
+				ptr++;
+				return;
+			}
+		} else {
+			if (l > 20000000) {
+				space += pulse;
+				if (space > IR_MAX_DURATION)
+					space = IR_MAX_DURATION;
+				space += l;
+				if (space > IR_MAX_DURATION)
+					space = IR_MAX_DURATION;
+				pulse = 0;
+				return;
+			}
+
+			ev.duration = space;
+			ev.pulse = false;
+			ir_raw_event_store_with_filter(rcdev, &ev);
+			ev.duration = pulse;
+			ev.pulse = true;
+			ir_raw_event_store_with_filter(rcdev, &ev);
+			ptr = 0;
+			pulse = 0;
+		}
+	}
+
+	ev.duration = l;
+	ev.pulse = is_pulse;
+	ir_raw_event_store_with_filter(rcdev, &ev);
+}
+
+static irqreturn_t serial_ir_irq_handler(int i, void *blah)
+{
+	ktime_t kt;
+	int counter, dcd;
+	u8 status;
+	ktime_t delkt;
+	unsigned int data;
+	static int last_dcd = -1;
+
+	if ((sinp(UART_IIR) & UART_IIR_NO_INT)) {
+		/* not our interrupt */
+		return IRQ_NONE;
+	}
+
+	counter = 0;
+	do {
+		counter++;
+		status = sinp(UART_MSR);
+		if (counter > RS_ISR_PASS_LIMIT) {
+			pr_warn("AIEEEE: We're caught!\n");
+			break;
+		}
+		if ((status & hardware[type].signal_pin_change)
+		    && sense != -1) {
+			/* get current time */
+			kt = ktime_get();
+
+			/*
+			 * 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.
+			 */
+
+			/* calc time since last interrupt in microseconds */
+			dcd = (status & hardware[type].signal_pin) ? 1 : 0;
+
+			if (dcd == last_dcd) {
+				pr_warn("ignoring spike: %d %d %llx %llx\n",
+					dcd, sense, ktime_to_us(kt),
+					ktime_to_us(lastkt));
+				continue;
+			}
+
+			delkt = ktime_sub(kt, lastkt);
+			if (ktime_compare(delkt, ktime_set(15, 0)) > 0) {
+				data = IR_MAX_DURATION; /* really long time */
+				if (!(dcd^sense)) {
+					/* sanity check */
+					pr_warn("AIEEEE: %d %d %llx %llx\n",
+						dcd, sense, ktime_to_us(kt),
+						ktime_to_us(lastkt));
+					/*
+					 * detecting pulse while this
+					 * MUST be a space!
+					 */
+					sense = sense ? 0 : 1;
+				}
+			} else
+				data = (unsigned int)ktime_to_ns(delkt);
+			frbwrite(data, !(dcd^sense));
+			lastkt = kt;
+			last_dcd = dcd;
+			ir_raw_event_handle(rcdev);
+		}
+	} while (!(sinp(UART_IIR) & UART_IIR_NO_INT)); /* still pending ? */
+	return IRQ_HANDLED;
+}
+
+
+static int hardware_init_port(void)
+{
+	u8 scratch, scratch2, scratch3;
+
+	/*
+	 * This is a simple port existence test, borrowed from the autoconfig
+	 * function in drivers/serial/8250.c
+	 */
+	scratch = sinp(UART_IER);
+	soutp(UART_IER, 0);
+#ifdef __i386__
+	outb(0xff, 0x080);
+#endif
+	scratch2 = sinp(UART_IER) & 0x0f;
+	soutp(UART_IER, 0x0f);
+#ifdef __i386__
+	outb(0x00, 0x080);
+#endif
+	scratch3 = sinp(UART_IER) & 0x0f;
+	soutp(UART_IER, scratch);
+	if (scratch2 != 0 || scratch3 != 0x0f) {
+		/* we fail, there's nothing here */
+		pr_err("port existence test failed, cannot continue\n");
+		return -ENODEV;
+	}
+
+	/* 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);
+
+	/* 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 IR_IRDEO:
+	case IR_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;
+	}
+
+	return 0;
+}
+
+static int serial_ir_probe(struct platform_device *dev)
+{
+	int i, nlow, nhigh, result;
+
+	result = devm_request_irq(&dev->dev, irq, serial_ir_irq_handler,
+			     (share_irq ? IRQF_SHARED : 0),
+			     DRIVER_NAME, &hardware);
+	if (result < 0) {
+		if (result == -EBUSY)
+			dev_err(&dev->dev, "IRQ %d busy\n", irq);
+		else if (result == -EINVAL)
+			dev_err(&dev->dev, "Bad irq number or handler\n");
+		return result;
+	}
+
+	/* Reserve io region. */
+	/*
+	 * 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)
+	     && (devm_request_mem_region(&dev->dev, iommap, 8 << ioshift,
+					 DRIVER_NAME) == NULL))
+	   || ((!iommap)
+	       && (devm_request_region(&dev->dev, io, 8,
+				       DRIVER_NAME) == NULL))) {
+		dev_err(&dev->dev, "port %04x already in use\n", io);
+		dev_warn(&dev->dev, "use 'setserial /dev/ttySX uart none'\n");
+		dev_warn(&dev->dev,
+			 "or compile the serial port driver as module and\n");
+		dev_warn(&dev->dev, "make sure this module is loaded first\n");
+		return -EBUSY;
+	}
+
+	result = hardware_init_port();
+	if (result < 0)
+		return result;
+
+	/* 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 */
+		msleep(500);
+
+		/*
+		 * 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++;
+			msleep(40);
+		}
+		sense = nlow >= nhigh ? 1 : 0;
+		dev_info(&dev->dev, "auto-detected active %s receiver\n",
+			 sense ? "low" : "high");
+	} else
+		dev_info(&dev->dev, "Manually using active %s receiver\n",
+			 sense ? "low" : "high");
+
+	dev_dbg(&dev->dev, "Interrupt %d, port %04x obtained\n", irq, io);
+	return 0;
+}
+
+static int serial_ir_open(struct rc_dev *rcdev)
+{
+	unsigned long flags;
+
+	/* initialize timestamp */
+	lastkt = ktime_get();
+
+	spin_lock_irqsave(&hardware[type].lock, flags);
+
+	/* Set DLAB 0. */
+	soutp(UART_LCR, sinp(UART_LCR) & (~UART_LCR_DLAB));
+
+	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
+
+	spin_unlock_irqrestore(&hardware[type].lock, flags);
+
+	return 0;
+}
+
+static void serial_ir_close(struct rc_dev *rcdev)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&hardware[type].lock, 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)));
+	spin_unlock_irqrestore(&hardware[type].lock, flags);
+}
+
+static int serial_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
+							unsigned int count)
+{
+	unsigned long flags;
+	long delta = 0;
+	int i;
+
+	spin_lock_irqsave(&hardware[type].lock, flags);
+	if (type == IR_IRDEO) {
+		/* DTR, RTS down */
+		on();
+	}
+	for (i = 0; i < count; i++) {
+		if (i%2)
+			hardware[type].send_space(txbuf[i] - delta);
+		else
+			delta = hardware[type].send_pulse(txbuf[i]);
+	}
+	off();
+	spin_unlock_irqrestore(&hardware[type].lock, flags);
+	return count;
+}
+
+static int serial_ir_tx_duty_cycle(struct rc_dev *dev, u32 cycle)
+{
+	return init_timing_params(cycle, freq);
+}
+
+static int serial_ir_tx_carrier(struct rc_dev *dev, u32 carrier)
+{
+	if (carrier > 500000 || carrier < 20000)
+		return -EINVAL;
+
+	return init_timing_params(duty_cycle, carrier);
+}
+
+static struct platform_device *serial_ir_dev;
+
+static int serial_ir_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 serial_ir_resume(struct platform_device *dev)
+{
+	unsigned long flags;
+	int result;
+
+	result = hardware_init_port();
+	if (result < 0)
+		return result;
+
+	spin_lock_irqsave(&hardware[type].lock, flags);
+	/* Enable Interrupt */
+	lastkt = ktime_get();
+	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
+	off();
+
+	spin_unlock_irqrestore(&hardware[type].lock, flags);
+
+	return 0;
+}
+
+static struct platform_driver serial_ir_driver = {
+	.probe		= serial_ir_probe,
+	.suspend	= serial_ir_suspend,
+	.resume		= serial_ir_resume,
+	.driver		= {
+		.name	= "serial_ir",
+	},
+};
+
+static int __init serial_ir_init(void)
+{
+	int result;
+
+	result = platform_driver_register(&serial_ir_driver);
+	if (result)
+		return result;
+
+	serial_ir_dev = platform_device_alloc("serial_ir", 0);
+	if (!serial_ir_dev) {
+		result = -ENOMEM;
+		goto exit_driver_unregister;
+	}
+
+	result = platform_device_add(serial_ir_dev);
+	if (result)
+		goto exit_device_put;
+
+	return 0;
+
+exit_device_put:
+	platform_device_put(serial_ir_dev);
+exit_driver_unregister:
+	platform_driver_unregister(&serial_ir_driver);
+	return result;
+}
+
+static void serial_ir_exit(void)
+{
+	platform_device_unregister(serial_ir_dev);
+	platform_driver_unregister(&serial_ir_driver);
+}
+
+static int __init serial_ir_init_module(void)
+{
+	int result;
+
+	switch (type) {
+	case IR_HOMEBREW:
+	case IR_IRDEO:
+	case IR_IRDEO_REMOTE:
+	case IR_ANIMAX:
+	case IR_IGOR:
+	case IR_NSLU2:
+		/* if nothing specified, use ttyS0/com1 and irq 4 */
+		io = io ? io : 0x3f8;
+		irq = irq ? irq : 4;
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (!softcarrier) {
+		switch (type) {
+		case IR_HOMEBREW:
+		case IR_IGOR:
+			hardware[type].set_send_carrier = false;
+			hardware[type].set_duty_cycle = false;
+			break;
+		}
+	}
+
+	/* make sure sense is either -1, 0, or 1 */
+	if (sense != -1)
+		sense = !!sense;
+
+	result = serial_ir_init();
+	if (result)
+		return result;
+
+	rcdev = devm_rc_allocate_device(&serial_ir_dev->dev);
+
+	if (hardware[type].send_pulse && hardware[type].send_space)
+		rcdev->tx_ir = serial_ir_tx;
+	if (hardware[type].set_send_carrier)
+		rcdev->s_tx_carrier = serial_ir_tx_carrier;
+	if (hardware[type].set_duty_cycle)
+		rcdev->s_tx_duty_cycle = serial_ir_tx_duty_cycle;
+
+	switch (type) {
+	case IR_HOMEBREW:
+		rcdev->input_name = "Serial IR type home-brew";
+		break;
+	case IR_IRDEO:
+		rcdev->input_name = "Serial IR type IRdeo";
+		break;
+	case IR_IRDEO_REMOTE:
+		rcdev->input_name = "Serial IR type IRdeo remote";
+		break;
+	case IR_ANIMAX:
+		rcdev->input_name = "Serial IR type AnimaX";
+		break;
+	case IR_IGOR:
+		rcdev->input_name = "Serial IR type IgorPlug";
+		break;
+	case IR_NSLU2:
+		rcdev->input_name = "Serial IR type NSLU2 RX:CTS2/TX:GreenLED)";
+		break;
+	}
+
+	rcdev->input_phys = DRIVER_NAME "/input0";
+	rcdev->input_id.bustype = BUS_HOST;
+	rcdev->input_id.vendor = 0x0001;
+	rcdev->input_id.product = 0x0001;
+	rcdev->input_id.version = 0x0100;
+	rcdev->open = serial_ir_open;
+	rcdev->close = serial_ir_close;
+	rcdev->dev.parent = &serial_ir_dev->dev;
+	rcdev->driver_type = RC_DRIVER_IR_RAW;
+	rcdev->allowed_protocols = RC_BIT_ALL;
+	rcdev->driver_name = DRIVER_NAME;
+	rcdev->map_name = RC_MAP_RC6_MCE;
+	rcdev->timeout = IR_DEFAULT_TIMEOUT;
+	rcdev->rx_resolution = 250000;
+
+	return rc_register_device(rcdev);
+}
+
+static void __exit serial_ir_exit_module(void)
+{
+	rc_unregister_device(rcdev);
+	serial_ir_exit();
+}
+
+
+module_init(serial_ir_init_module);
+module_exit(serial_ir_exit_module);
+
+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);
+MODULE_PARM_DESC(type, "Hardware type (0 = home-brew, 1 = IRdeo, 2 = IRdeo Remote, 3 = AnimaX, 4 = IgorPlug, 5 = NSLU2 RX:CTS2/TX:GreenLED)");
+
+module_param(io, int, 0444);
+MODULE_PARM_DESC(io, "I/O address base (0x3f8 or 0x2f8)");
+
+/* 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/drivers/tty/serial/8250/8250.c serial_in()/out()
+ */
+module_param(ioshift, int, 0444);
+MODULE_PARM_DESC(ioshift, "shift I/O register offset (0 = no shift)");
+
+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, int, 0444);
+MODULE_PARM_DESC(sense, "Override autodetection of IR receiver circuit (0 = active high, 1 = active low )");
+
+#ifdef CONFIG_IR_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, default on)");