drivers/media/rc/rc-ir-raw.c - linux - Git at Google

 /* rc-ir-raw.c - handle IR pulse/space events
  *
  * Copyright (C) 2010 by Mauro Carvalho Chehab
  *
  * 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 version 2 of the License.
  *
  *  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.
  */

 #include <linux/export.h>
 #include <linux/kthread.h>
 #include <linux/mutex.h>
 #include <linux/kmod.h>
 #include <linux/sched.h>
 #include <linux/freezer.h>
 #include "rc-core-priv.h"

 /* Define the max number of pulse/space transitions to buffer */
 #define MAX_IR_EVENT_SIZE      512

 /* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */
 static LIST_HEAD(ir_raw_client_list);

 /* Used to handle IR raw handler extensions */
 static DEFINE_MUTEX(ir_raw_handler_lock);
 static LIST_HEAD(ir_raw_handler_list);
 static u64 available_protocols;
 static u64 encode_protocols;

 static int ir_raw_event_thread(void *data)
 {
 	struct ir_raw_event ev;
 	struct ir_raw_handler *handler;
 	struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data;
 	int retval;

 	while (!kthread_should_stop()) {

 		spin_lock_irq(&raw->lock);
 		retval = kfifo_len(&raw->kfifo);

 		if (retval < sizeof(ev)) {
 			set_current_state(TASK_INTERRUPTIBLE);

 			if (kthread_should_stop())
 				set_current_state(TASK_RUNNING);

 			spin_unlock_irq(&raw->lock);
 			schedule();
 			continue;
 		}

 		retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));
 		spin_unlock_irq(&raw->lock);

 		mutex_lock(&ir_raw_handler_lock);
 		list_for_each_entry(handler, &ir_raw_handler_list, list)
 			handler->decode(raw->dev, ev);
 		raw->prev_ev = ev;
 		mutex_unlock(&ir_raw_handler_lock);
 	}

 	return 0;
 }

 /**
  * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
  * @dev:	the struct rc_dev device descriptor
  * @ev:		the struct ir_raw_event descriptor of the pulse/space
  *
  * This routine (which may be called from an interrupt context) stores a
  * pulse/space duration for the raw ir decoding state machines. Pulses are
  * signalled as positive values and spaces as negative values. A zero value
  * will reset the decoding state machines.
  */
 int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev)
 {
 	if (!dev->raw)
 		return -EINVAL;

 	IR_dprintk(2, "sample: (%05dus %s)\n",
 		   TO_US(ev->duration), TO_STR(ev->pulse));

 	if (kfifo_in(&dev->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
 		return -ENOMEM;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store);

 /**
  * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
  * @dev:	the struct rc_dev device descriptor
  * @type:	the type of the event that has occurred
  *
  * This routine (which may be called from an interrupt context) is used to
  * store the beginning of an ir pulse or space (or the start/end of ir
  * reception) for the raw ir decoding state machines. This is used by
  * hardware which does not provide durations directly but only interrupts
  * (or similar events) on state change.
  */
 int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type)
 {
 	ktime_t			now;
 	s64			delta; /* ns */
 	DEFINE_IR_RAW_EVENT(ev);
 	int			rc = 0;
 	int			delay;

 	if (!dev->raw)
 		return -EINVAL;

 	now = ktime_get();
 	delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event));
 	delay = MS_TO_NS(dev->input_dev->rep[REP_DELAY]);

 	/* Check for a long duration since last event or if we're
 	 * being called for the first time, note that delta can't
 	 * possibly be negative.
 	 */
 	if (delta > delay || !dev->raw->last_type)
 		type |= IR_START_EVENT;
 	else
 		ev.duration = delta;

 	if (type & IR_START_EVENT)
 		ir_raw_event_reset(dev);
 	else if (dev->raw->last_type & IR_SPACE) {
 		ev.pulse = false;
 		rc = ir_raw_event_store(dev, &ev);
 	} else if (dev->raw->last_type & IR_PULSE) {
 		ev.pulse = true;
 		rc = ir_raw_event_store(dev, &ev);
 	} else
 		return 0;

 	dev->raw->last_event = now;
 	dev->raw->last_type = type;
 	return rc;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);

 /**
  * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing
  * @dev:	the struct rc_dev device descriptor
  * @type:	the type of the event that has occurred
  *
  * This routine (which may be called from an interrupt context) works
  * in similar manner to ir_raw_event_store_edge.
  * This routine is intended for devices with limited internal buffer
  * It automerges samples of same type, and handles timeouts. Returns non-zero
  * if the event was added, and zero if the event was ignored due to idle
  * processing.
  */
 int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev)
 {
 	if (!dev->raw)
 		return -EINVAL;

 	/* Ignore spaces in idle mode */
 	if (dev->idle && !ev->pulse)
 		return 0;
 	else if (dev->idle)
 		ir_raw_event_set_idle(dev, false);

 	if (!dev->raw->this_ev.duration)
 		dev->raw->this_ev = *ev;
 	else if (ev->pulse == dev->raw->this_ev.pulse)
 		dev->raw->this_ev.duration += ev->duration;
 	else {
 		ir_raw_event_store(dev, &dev->raw->this_ev);
 		dev->raw->this_ev = *ev;
 	}

 	/* Enter idle mode if nessesary */
 	if (!ev->pulse && dev->timeout &&
 	    dev->raw->this_ev.duration >= dev->timeout)
 		ir_raw_event_set_idle(dev, true);

 	return 1;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter);

 /**
  * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
  * @dev:	the struct rc_dev device descriptor
  * @idle:	whether the device is idle or not
  */
 void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
 {
 	if (!dev->raw)
 		return;

 	IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave");

 	if (idle) {
 		dev->raw->this_ev.timeout = true;
 		ir_raw_event_store(dev, &dev->raw->this_ev);
 		init_ir_raw_event(&dev->raw->this_ev);
 	}

 	if (dev->s_idle)
 		dev->s_idle(dev, idle);

 	dev->idle = idle;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_set_idle);

 /**
  * ir_raw_event_handle() - schedules the decoding of stored ir data
  * @dev:	the struct rc_dev device descriptor
  *
  * This routine will tell rc-core to start decoding stored ir data.
  */
 void ir_raw_event_handle(struct rc_dev *dev)
 {
 	unsigned long flags;

 	if (!dev->raw)
 		return;

 	spin_lock_irqsave(&dev->raw->lock, flags);
 	wake_up_process(dev->raw->thread);
 	spin_unlock_irqrestore(&dev->raw->lock, flags);
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_handle);

 /* used internally by the sysfs interface */
 u64
 ir_raw_get_allowed_protocols(void)
 {
 	u64 protocols;
 	mutex_lock(&ir_raw_handler_lock);
 	protocols = available_protocols;
 	mutex_unlock(&ir_raw_handler_lock);
 	return protocols;
 }

 /* used internally by the sysfs interface */
 u64
 ir_raw_get_encode_protocols(void)
 {
 	u64 protocols;

 	mutex_lock(&ir_raw_handler_lock);
 	protocols = encode_protocols;
 	mutex_unlock(&ir_raw_handler_lock);
 	return protocols;
 }

 static int change_protocol(struct rc_dev *dev, u64 *rc_type)
 {
 	/* the caller will update dev->enabled_protocols */
 	return 0;
 }

 /**
  * ir_raw_gen_manchester() - Encode data with Manchester (bi-phase) modulation.
  * @ev:		Pointer to pointer to next free event. *@ev is incremented for
  *		each raw event filled.
  * @max:	Maximum number of raw events to fill.
  * @timings:	Manchester modulation timings.
  * @n:		Number of bits of data.
  * @data:	Data bits to encode.
  *
  * Encodes the @n least significant bits of @data using Manchester (bi-phase)
  * modulation with the timing characteristics described by @timings, writing up
  * to @max raw IR events using the *@ev pointer.
  *
  * Returns:	0 on success.
  *		-ENOBUFS if there isn't enough space in the array to fit the
  *		full encoded data. In this case all @max events will have been
  *		written.
  */
 int ir_raw_gen_manchester(struct ir_raw_event **ev, unsigned int max,
 			  const struct ir_raw_timings_manchester *timings,
 			  unsigned int n, unsigned int data)
 {
 	bool need_pulse;
 	unsigned int i;
 	int ret = -ENOBUFS;

 	i = 1 << (n - 1);

 	if (timings->leader) {
 		if (!max--)
 			return ret;
 		if (timings->pulse_space_start) {
 			init_ir_raw_event_duration((*ev)++, 1, timings->leader);

 			if (!max--)
 				return ret;
 			init_ir_raw_event_duration((*ev), 0, timings->leader);
 		} else {
 			init_ir_raw_event_duration((*ev), 1, timings->leader);
 		}
 		i >>= 1;
 	} else {
 		/* continue existing signal */
 		--(*ev);
 	}
 	/* from here on *ev will point to the last event rather than the next */

 	while (n && i > 0) {
 		need_pulse = !(data & i);
 		if (timings->invert)
 			need_pulse = !need_pulse;
 		if (need_pulse == !!(*ev)->pulse) {
 			(*ev)->duration += timings->clock;
 		} else {
 			if (!max--)
 				goto nobufs;
 			init_ir_raw_event_duration(++(*ev), need_pulse,
 						   timings->clock);
 		}

 		if (!max--)
 			goto nobufs;
 		init_ir_raw_event_duration(++(*ev), !need_pulse,
 					   timings->clock);
 		i >>= 1;
 	}

 	if (timings->trailer_space) {
 		if (!(*ev)->pulse)
 			(*ev)->duration += timings->trailer_space;
 		else if (!max--)
 			goto nobufs;
 		else
 			init_ir_raw_event_duration(++(*ev), 0,
 						   timings->trailer_space);
 	}

 	ret = 0;
 nobufs:
 	/* point to the next event rather than last event before returning */
 	++(*ev);
 	return ret;
 }
 EXPORT_SYMBOL(ir_raw_gen_manchester);

 /**
  * ir_raw_encode_scancode() - Encode a scancode as raw events
  *
  * @protocols:		permitted protocols
  * @scancode:		scancode filter describing a single scancode
  * @events:		array of raw events to write into
  * @max:		max number of raw events
  *
  * Attempts to encode the scancode as raw events.
  *
  * Returns:	The number of events written.
  *		-ENOBUFS if there isn't enough space in the array to fit the
  *		encoding. In this case all @max events will have been written.
  *		-EINVAL if the scancode is ambiguous or invalid, or if no
  *		compatible encoder was found.
  */
 int ir_raw_encode_scancode(u64 protocols,
 			   const struct rc_scancode_filter *scancode,
 			   struct ir_raw_event *events, unsigned int max)
 {
 	struct ir_raw_handler *handler;
 	int ret = -EINVAL;

 	mutex_lock(&ir_raw_handler_lock);
 	list_for_each_entry(handler, &ir_raw_handler_list, list) {
 		if (handler->protocols & protocols && handler->encode) {
 			ret = handler->encode(protocols, scancode, events, max);
 			if (ret >= 0 || ret == -ENOBUFS)
 				break;
 		}
 	}
 	mutex_unlock(&ir_raw_handler_lock);

 	return ret;
 }
 EXPORT_SYMBOL(ir_raw_encode_scancode);

 /*
  * Used to (un)register raw event clients
  */
 int ir_raw_event_register(struct rc_dev *dev)
 {
 	int rc;
 	struct ir_raw_handler *handler;

 	if (!dev)
 		return -EINVAL;

 	dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL);
 	if (!dev->raw)
 		return -ENOMEM;

 	dev->raw->dev = dev;
 	dev->change_protocol = change_protocol;
 	rc = kfifo_alloc(&dev->raw->kfifo,
 			 sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE,
 			 GFP_KERNEL);
 	if (rc < 0)
 		goto out;

 	spin_lock_init(&dev->raw->lock);
 	dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw,
 				       "rc%ld", dev->devno);

 	if (IS_ERR(dev->raw->thread)) {
 		rc = PTR_ERR(dev->raw->thread);
 		goto out;
 	}

 	mutex_lock(&ir_raw_handler_lock);
 	list_add_tail(&dev->raw->list, &ir_raw_client_list);
 	list_for_each_entry(handler, &ir_raw_handler_list, list)
 		if (handler->raw_register)
 			handler->raw_register(dev);
 	mutex_unlock(&ir_raw_handler_lock);

 	return 0;

 out:
 	kfree(dev->raw);
 	dev->raw = NULL;
 	return rc;
 }

 void ir_raw_event_unregister(struct rc_dev *dev)
 {
 	struct ir_raw_handler *handler;

 	if (!dev || !dev->raw)
 		return;

 	kthread_stop(dev->raw->thread);

 	mutex_lock(&ir_raw_handler_lock);
 	list_del(&dev->raw->list);
 	list_for_each_entry(handler, &ir_raw_handler_list, list)
 		if (handler->raw_unregister)
 			handler->raw_unregister(dev);
 	mutex_unlock(&ir_raw_handler_lock);

 	kfifo_free(&dev->raw->kfifo);
 	kfree(dev->raw);
 	dev->raw = NULL;
 }

 /*
  * Extension interface - used to register the IR decoders
  */

 int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
 {
 	struct ir_raw_event_ctrl *raw;

 	mutex_lock(&ir_raw_handler_lock);
 	list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
 	if (ir_raw_handler->raw_register)
 		list_for_each_entry(raw, &ir_raw_client_list, list)
 			ir_raw_handler->raw_register(raw->dev);
 	available_protocols |= ir_raw_handler->protocols;
 	if (ir_raw_handler->encode)
 		encode_protocols |= ir_raw_handler->protocols;
 	mutex_unlock(&ir_raw_handler_lock);

 	return 0;
 }
 EXPORT_SYMBOL(ir_raw_handler_register);

 void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
 {
 	struct ir_raw_event_ctrl *raw;

 	mutex_lock(&ir_raw_handler_lock);
 	list_del(&ir_raw_handler->list);
 	if (ir_raw_handler->raw_unregister)
 		list_for_each_entry(raw, &ir_raw_client_list, list)
 			ir_raw_handler->raw_unregister(raw->dev);
 	available_protocols &= ~ir_raw_handler->protocols;
 	if (ir_raw_handler->encode)
 		encode_protocols &= ~ir_raw_handler->protocols;
 	mutex_unlock(&ir_raw_handler_lock);
 }
 EXPORT_SYMBOL(ir_raw_handler_unregister);

 void ir_raw_init(void)
 {
 	/* Load the decoder modules */

 	load_nec_decode();
 	load_rc5_decode();
 	load_rc6_decode();
 	load_jvc_decode();
 	load_sony_decode();
 	load_sanyo_decode();
 	load_sharp_decode();
 	load_mce_kbd_decode();
 	load_lirc_codec();
 	load_xmp_decode();

 	/* If needed, we may later add some init code. In this case,
 	   it is needed to change the CONFIG_MODULE test at rc-core.h
 	 */
 }
	/* rc-ir-raw.c - handle IR pulse/space events
	*
	* Copyright (C) 2010 by Mauro Carvalho Chehab
	*
	* 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 version 2 of the License.
	*
	* 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.
	*/

	#include <linux/export.h>
	#include <linux/kthread.h>
	#include <linux/mutex.h>
	#include <linux/kmod.h>
	#include <linux/sched.h>
	#include <linux/freezer.h>
	#include "rc-core-priv.h"

	/* Define the max number of pulse/space transitions to buffer */
	#define MAX_IR_EVENT_SIZE 512

	/* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */
	static LIST_HEAD(ir_raw_client_list);

	/* Used to handle IR raw handler extensions */
	static DEFINE_MUTEX(ir_raw_handler_lock);
	static LIST_HEAD(ir_raw_handler_list);
	static u64 available_protocols;
	static u64 encode_protocols;

	static int ir_raw_event_thread(void *data)
	{
	struct ir_raw_event ev;
	struct ir_raw_handler *handler;
	struct ir_raw_event_ctrl raw = (struct ir_raw_event_ctrl )data;
	int retval;

	while (!kthread_should_stop()) {

	spin_lock_irq(&raw->lock);
	retval = kfifo_len(&raw->kfifo);

	if (retval < sizeof(ev)) {
	set_current_state(TASK_INTERRUPTIBLE);

	if (kthread_should_stop())
	set_current_state(TASK_RUNNING);

	spin_unlock_irq(&raw->lock);
	schedule();
	continue;
	}

	retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));
	spin_unlock_irq(&raw->lock);

	mutex_lock(&ir_raw_handler_lock);
	list_for_each_entry(handler, &ir_raw_handler_list, list)
	handler->decode(raw->dev, ev);
	raw->prev_ev = ev;
	mutex_unlock(&ir_raw_handler_lock);
	}

	return 0;
	}

	/**
	* ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
	* @dev: the struct rc_dev device descriptor
	* @ev: the struct ir_raw_event descriptor of the pulse/space
	*
	* This routine (which may be called from an interrupt context) stores a
	* pulse/space duration for the raw ir decoding state machines. Pulses are
	* signalled as positive values and spaces as negative values. A zero value
	* will reset the decoding state machines.
	*/
	int ir_raw_event_store(struct rc_dev dev, struct ir_raw_event ev)
	{
	if (!dev->raw)
	return -EINVAL;

	IR_dprintk(2, "sample: (%05dus %s)\n",
	TO_US(ev->duration), TO_STR(ev->pulse));

	if (kfifo_in(&dev->raw->kfifo, ev, sizeof(ev)) != sizeof(ev))
	return -ENOMEM;

	return 0;
	}
	EXPORT_SYMBOL_GPL(ir_raw_event_store);

	/**
	* ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
	* @dev: the struct rc_dev device descriptor
	* @type: the type of the event that has occurred
	*
	* This routine (which may be called from an interrupt context) is used to
	* store the beginning of an ir pulse or space (or the start/end of ir
	* reception) for the raw ir decoding state machines. This is used by
	* hardware which does not provide durations directly but only interrupts
	* (or similar events) on state change.
	*/
	int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type)
	{
	ktime_t now;
	s64 delta; /* ns */
	DEFINE_IR_RAW_EVENT(ev);
	int rc = 0;
	int delay;

	if (!dev->raw)
	return -EINVAL;

	now = ktime_get();
	delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event));
	delay = MS_TO_NS(dev->input_dev->rep[REP_DELAY]);

	/* Check for a long duration since last event or if we're
	* being called for the first time, note that delta can't
	* possibly be negative.
	*/
	if (delta > delay \|\| !dev->raw->last_type)
	type \|= IR_START_EVENT;
	else
	ev.duration = delta;

	if (type & IR_START_EVENT)
	ir_raw_event_reset(dev);
	else if (dev->raw->last_type & IR_SPACE) {
	ev.pulse = false;
	rc = ir_raw_event_store(dev, &ev);
	} else if (dev->raw->last_type & IR_PULSE) {
	ev.pulse = true;
	rc = ir_raw_event_store(dev, &ev);
	} else
	return 0;

	dev->raw->last_event = now;
	dev->raw->last_type = type;
	return rc;
	}
	EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);

	/**
	* ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing
	* @dev: the struct rc_dev device descriptor
	* @type: the type of the event that has occurred
	*
	* This routine (which may be called from an interrupt context) works
	* in similar manner to ir_raw_event_store_edge.
	* This routine is intended for devices with limited internal buffer
	* It automerges samples of same type, and handles timeouts. Returns non-zero
	* if the event was added, and zero if the event was ignored due to idle
	* processing.
	*/
	int ir_raw_event_store_with_filter(struct rc_dev dev, struct ir_raw_event ev)
	{
	if (!dev->raw)
	return -EINVAL;

	/* Ignore spaces in idle mode */
	if (dev->idle && !ev->pulse)
	return 0;
	else if (dev->idle)
	ir_raw_event_set_idle(dev, false);

	if (!dev->raw->this_ev.duration)
	dev->raw->this_ev = *ev;
	else if (ev->pulse == dev->raw->this_ev.pulse)
	dev->raw->this_ev.duration += ev->duration;
	else {
	ir_raw_event_store(dev, &dev->raw->this_ev);
	dev->raw->this_ev = *ev;
	}

	/* Enter idle mode if nessesary */
	if (!ev->pulse && dev->timeout &&
	dev->raw->this_ev.duration >= dev->timeout)
	ir_raw_event_set_idle(dev, true);

	return 1;
	}
	EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter);

	/**
	* ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
	* @dev: the struct rc_dev device descriptor
	* @idle: whether the device is idle or not
	*/
	void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
	{
	if (!dev->raw)
	return;

	IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave");

	if (idle) {
	dev->raw->this_ev.timeout = true;
	ir_raw_event_store(dev, &dev->raw->this_ev);
	init_ir_raw_event(&dev->raw->this_ev);
	}

	if (dev->s_idle)
	dev->s_idle(dev, idle);

	dev->idle = idle;
	}
	EXPORT_SYMBOL_GPL(ir_raw_event_set_idle);

	/**
	* ir_raw_event_handle() - schedules the decoding of stored ir data
	* @dev: the struct rc_dev device descriptor
	*
	* This routine will tell rc-core to start decoding stored ir data.
	*/
	void ir_raw_event_handle(struct rc_dev *dev)
	{
	unsigned long flags;

	if (!dev->raw)
	return;

	spin_lock_irqsave(&dev->raw->lock, flags);
	wake_up_process(dev->raw->thread);
	spin_unlock_irqrestore(&dev->raw->lock, flags);
	}
	EXPORT_SYMBOL_GPL(ir_raw_event_handle);

	/* used internally by the sysfs interface */
	u64
	ir_raw_get_allowed_protocols(void)
	{
	u64 protocols;
	mutex_lock(&ir_raw_handler_lock);
	protocols = available_protocols;
	mutex_unlock(&ir_raw_handler_lock);
	return protocols;
	}

	/* used internally by the sysfs interface */
	u64
	ir_raw_get_encode_protocols(void)
	{
	u64 protocols;

	mutex_lock(&ir_raw_handler_lock);
	protocols = encode_protocols;
	mutex_unlock(&ir_raw_handler_lock);
	return protocols;
	}

	static int change_protocol(struct rc_dev dev, u64 rc_type)
	{
	/* the caller will update dev->enabled_protocols */
	return 0;
	}

	/**
	* ir_raw_gen_manchester() - Encode data with Manchester (bi-phase) modulation.
	* @ev: Pointer to pointer to next free event. *@ev is incremented for
	* each raw event filled.
	* @max: Maximum number of raw events to fill.
	* @timings: Manchester modulation timings.
	* @n: Number of bits of data.
	* @data: Data bits to encode.
	*
	* Encodes the @n least significant bits of @data using Manchester (bi-phase)
	* modulation with the timing characteristics described by @timings, writing up
	* to @max raw IR events using the *@ev pointer.
	*
	* Returns: 0 on success.
	* -ENOBUFS if there isn't enough space in the array to fit the
	* full encoded data. In this case all @max events will have been
	* written.
	*/
	int ir_raw_gen_manchester(struct ir_raw_event **ev, unsigned int max,
	const struct ir_raw_timings_manchester *timings,
	unsigned int n, unsigned int data)
	{
	bool need_pulse;
	unsigned int i;
	int ret = -ENOBUFS;

	i = 1 << (n - 1);

	if (timings->leader) {
	if (!max--)
	return ret;
	if (timings->pulse_space_start) {
	init_ir_raw_event_duration((*ev)++, 1, timings->leader);

	if (!max--)
	return ret;
	init_ir_raw_event_duration((*ev), 0, timings->leader);
	} else {
	init_ir_raw_event_duration((*ev), 1, timings->leader);
	}
	i >>= 1;
	} else {
	/* continue existing signal */
	--(*ev);
	}
	/* from here on ev will point to the last event rather than the next /

	while (n && i > 0) {
	need_pulse = !(data & i);
	if (timings->invert)
	need_pulse = !need_pulse;
	if (need_pulse == !!(*ev)->pulse) {
	(*ev)->duration += timings->clock;
	} else {
	if (!max--)
	goto nobufs;
	init_ir_raw_event_duration(++(*ev), need_pulse,
	timings->clock);
	}

	if (!max--)
	goto nobufs;
	init_ir_raw_event_duration(++(*ev), !need_pulse,
	timings->clock);
	i >>= 1;
	}

	if (timings->trailer_space) {
	if (!(*ev)->pulse)
	(*ev)->duration += timings->trailer_space;
	else if (!max--)
	goto nobufs;
	else
	init_ir_raw_event_duration(++(*ev), 0,
	timings->trailer_space);
	}

	ret = 0;
	nobufs:
	/* point to the next event rather than last event before returning */
	++(*ev);
	return ret;
	}
	EXPORT_SYMBOL(ir_raw_gen_manchester);

	/**
	* ir_raw_encode_scancode() - Encode a scancode as raw events
	*
	* @protocols: permitted protocols
	* @scancode: scancode filter describing a single scancode
	* @events: array of raw events to write into
	* @max: max number of raw events
	*
	* Attempts to encode the scancode as raw events.
	*
	* Returns: The number of events written.
	* -ENOBUFS if there isn't enough space in the array to fit the
	* encoding. In this case all @max events will have been written.
	* -EINVAL if the scancode is ambiguous or invalid, or if no
	* compatible encoder was found.
	*/
	int ir_raw_encode_scancode(u64 protocols,
	const struct rc_scancode_filter *scancode,
	struct ir_raw_event *events, unsigned int max)
	{
	struct ir_raw_handler *handler;
	int ret = -EINVAL;

	mutex_lock(&ir_raw_handler_lock);
	list_for_each_entry(handler, &ir_raw_handler_list, list) {
	if (handler->protocols & protocols && handler->encode) {
	ret = handler->encode(protocols, scancode, events, max);
	if (ret >= 0 \|\| ret == -ENOBUFS)
	break;
	}
	}
	mutex_unlock(&ir_raw_handler_lock);

	return ret;
	}
	EXPORT_SYMBOL(ir_raw_encode_scancode);

	/*
	* Used to (un)register raw event clients
	*/
	int ir_raw_event_register(struct rc_dev *dev)
	{
	int rc;
	struct ir_raw_handler *handler;

	if (!dev)
	return -EINVAL;

	dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL);
	if (!dev->raw)
	return -ENOMEM;

	dev->raw->dev = dev;
	dev->change_protocol = change_protocol;
	rc = kfifo_alloc(&dev->raw->kfifo,
	sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE,
	GFP_KERNEL);
	if (rc < 0)
	goto out;

	spin_lock_init(&dev->raw->lock);
	dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw,
	"rc%ld", dev->devno);

	if (IS_ERR(dev->raw->thread)) {
	rc = PTR_ERR(dev->raw->thread);
	goto out;
	}

	mutex_lock(&ir_raw_handler_lock);
	list_add_tail(&dev->raw->list, &ir_raw_client_list);
	list_for_each_entry(handler, &ir_raw_handler_list, list)
	if (handler->raw_register)
	handler->raw_register(dev);
	mutex_unlock(&ir_raw_handler_lock);

	return 0;

	out:
	kfree(dev->raw);
	dev->raw = NULL;
	return rc;
	}

	void ir_raw_event_unregister(struct rc_dev *dev)
	{
	struct ir_raw_handler *handler;

	if (!dev \|\| !dev->raw)
	return;

	kthread_stop(dev->raw->thread);

	mutex_lock(&ir_raw_handler_lock);
	list_del(&dev->raw->list);
	list_for_each_entry(handler, &ir_raw_handler_list, list)
	if (handler->raw_unregister)
	handler->raw_unregister(dev);
	mutex_unlock(&ir_raw_handler_lock);

	kfifo_free(&dev->raw->kfifo);
	kfree(dev->raw);
	dev->raw = NULL;
	}

	/*
	* Extension interface - used to register the IR decoders
	*/

	int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
	{
	struct ir_raw_event_ctrl *raw;

	mutex_lock(&ir_raw_handler_lock);
	list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
	if (ir_raw_handler->raw_register)
	list_for_each_entry(raw, &ir_raw_client_list, list)
	ir_raw_handler->raw_register(raw->dev);
	available_protocols \|= ir_raw_handler->protocols;
	if (ir_raw_handler->encode)
	encode_protocols \|= ir_raw_handler->protocols;
	mutex_unlock(&ir_raw_handler_lock);

	return 0;
	}
	EXPORT_SYMBOL(ir_raw_handler_register);

	void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
	{
	struct ir_raw_event_ctrl *raw;

	mutex_lock(&ir_raw_handler_lock);
	list_del(&ir_raw_handler->list);
	if (ir_raw_handler->raw_unregister)
	list_for_each_entry(raw, &ir_raw_client_list, list)
	ir_raw_handler->raw_unregister(raw->dev);
	available_protocols &= ~ir_raw_handler->protocols;
	if (ir_raw_handler->encode)
	encode_protocols &= ~ir_raw_handler->protocols;
	mutex_unlock(&ir_raw_handler_lock);
	}
	EXPORT_SYMBOL(ir_raw_handler_unregister);

	void ir_raw_init(void)
	{
	/* Load the decoder modules */

	load_nec_decode();
	load_rc5_decode();
	load_rc6_decode();
	load_jvc_decode();
	load_sony_decode();
	load_sanyo_decode();
	load_sharp_decode();
	load_mce_kbd_decode();
	load_lirc_codec();
	load_xmp_decode();

	/* If needed, we may later add some init code. In this case,
	it is needed to change the CONFIG_MODULE test at rc-core.h
	*/
	}