include/media/ir-core.h

/*
 * Remote Controller core header
 *
 * Copyright (C) 2009-2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
 *
 * 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.
 */

#ifndef _IR_CORE
#define _IR_CORE

#include <linux/spinlock.h>
#include <linux/kfifo.h>
#include <linux/time.h>
#include <linux/timer.h>
#include <media/rc-map.h>

extern int ir_core_debug;
#define IR_dprintk(level, fmt, arg...)	if (ir_core_debug >= level) \
	printk(KERN_DEBUG "%s: " fmt , __func__, ## arg)

enum rc_driver_type {
	RC_DRIVER_SCANCODE = 0,	/* Driver or hardware generates a scancode */
	RC_DRIVER_IR_RAW,	/* Needs a Infra-Red pulse/space decoder */
};

enum raw_event_type {
	IR_SPACE	= (1 << 0),
	IR_PULSE	= (1 << 1),
	IR_START_EVENT	= (1 << 2),
	IR_STOP_EVENT	= (1 << 3),
};

/**
 * struct ir_dev_props - Allow caller drivers to set special properties
 * @driver_type: specifies if the driver or hardware have already a decoder,
 *	or if it needs to use the IR raw event decoders to produce a scancode
 * @allowed_protos: bitmask with the supported IR_TYPE_* protocols
 * @scanmask: some hardware decoders are not capable of providing the full
 *	scancode to the application. As this is a hardware limit, we can't do
 *	anything with it. Yet, as the same keycode table can be used with other
 *	devices, a mask is provided to allow its usage. Drivers should generally
 *	leave this field in blank
 * @priv: driver-specific data, to be used on the callbacks
 * @change_protocol: allow changing the protocol used on hardware decoders
 * @open: callback to allow drivers to enable polling/irq when IR input device
 *	is opened.
 * @close: callback to allow drivers to disable polling/irq when IR input device
 *	is opened.
 */
struct ir_dev_props {
	enum rc_driver_type	driver_type;
	unsigned long		allowed_protos;
	u32			scanmask;
	void 			*priv;
	int			(*change_protocol)(void *priv, u64 ir_type);
	int			(*open)(void *priv);
	void			(*close)(void *priv);
};

struct ir_raw_event_ctrl {
	struct work_struct		rx_work;	/* for the rx decoding workqueue */
	struct kfifo			kfifo;		/* fifo for the pulse/space durations */
	ktime_t				last_event;	/* when last event occurred */
	enum raw_event_type		last_type;	/* last event type */
	struct input_dev		*input_dev;	/* pointer to the parent input_dev */
};

struct ir_input_dev {
	struct device			dev;		/* device */
	char				*driver_name;	/* Name of the driver module */
	struct ir_scancode_table	rc_tab;		/* scan/key table */
	unsigned long			devno;		/* device number */
	const struct ir_dev_props	*props;		/* Device properties */
	struct ir_raw_event_ctrl	*raw;		/* for raw pulse/space events */
	struct input_dev		*input_dev;	/* the input device associated with this device */

	/* key info - needed by IR keycode handlers */
	spinlock_t			keylock;	/* protects the below members */
	bool				keypressed;	/* current state */
	unsigned long			keyup_jiffies;	/* when should the current keypress be released? */
	struct timer_list		timer_keyup;	/* timer for releasing a keypress */
	u32				last_keycode;	/* keycode of last command */
	u32				last_scancode;	/* scancode of last command */
	u8				last_toggle;	/* toggle of last command */
};

struct ir_raw_handler {
	struct list_head list;

	int (*decode)(struct input_dev *input_dev, s64 duration);
	int (*raw_register)(struct input_dev *input_dev);
	int (*raw_unregister)(struct input_dev *input_dev);
};

#define to_ir_input_dev(_attr) container_of(_attr, struct ir_input_dev, attr)

/* Routines from ir-keytable.c */

u32 ir_g_keycode_from_table(struct input_dev *input_dev,
			    u32 scancode);
void ir_repeat(struct input_dev *dev);
void ir_keydown(struct input_dev *dev, int scancode, u8 toggle);
int __ir_input_register(struct input_dev *dev,
		      const struct ir_scancode_table *ir_codes,
		      const struct ir_dev_props *props,
		      const char *driver_name);

static inline int ir_input_register(struct input_dev *dev,
		      const char *map_name,
		      const struct ir_dev_props *props,
		      const char *driver_name) {
	struct ir_scancode_table *ir_codes;
	struct ir_input_dev *ir_dev;
	int rc;

	if (!map_name)
		return -EINVAL;

	ir_codes = get_rc_map(map_name);
	if (!ir_codes)
		return -EINVAL;

	rc = __ir_input_register(dev, ir_codes, props, driver_name);
	if (rc < 0)
		return -EINVAL;

	ir_dev = input_get_drvdata(dev);

	if (!rc && ir_dev->props && ir_dev->props->change_protocol)
		rc = ir_dev->props->change_protocol(ir_dev->props->priv,
						    ir_codes->ir_type);

	return rc;
}

void ir_input_unregister(struct input_dev *input_dev);

/* Routines from ir-sysfs.c */

int ir_register_class(struct input_dev *input_dev);
void ir_unregister_class(struct input_dev *input_dev);

/* Routines from ir-raw-event.c */
int ir_raw_event_register(struct input_dev *input_dev);
void ir_raw_event_unregister(struct input_dev *input_dev);
void ir_raw_event_handle(struct input_dev *input_dev);
int ir_raw_event_store(struct input_dev *input_dev, s64 duration);
int ir_raw_event_store_edge(struct input_dev *input_dev, enum raw_event_type type);
static inline void ir_raw_event_reset(struct input_dev *input_dev)
{
	ir_raw_event_store(input_dev, 0);
	ir_raw_event_handle(input_dev);
}
int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler);
void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler);
void ir_raw_init(void);

/* from ir-nec-decoder.c */
#ifdef CONFIG_IR_NEC_DECODER_MODULE
#define load_nec_decode()	request_module("ir-nec-decoder")
#else
#define load_nec_decode()	0
#endif

/* from ir-rc5-decoder.c */
#ifdef CONFIG_IR_RC5_DECODER_MODULE
#define load_rc5_decode()	request_module("ir-rc5-decoder")
#else
#define load_rc5_decode()	0
#endif

/* macros for ir decoders */
#define PULSE(units)				((units))
#define SPACE(units)				(-(units))
#define IS_RESET(duration)			((duration) == 0)
#define IS_PULSE(duration)			((duration) > 0)
#define IS_SPACE(duration)			((duration) < 0)
#define DURATION(duration)			(abs((duration)))
#define IS_TRANSITION(x, y)			((x) * (y) < 0)
#define DECREASE_DURATION(duration, amount)			\
	do {							\
		if (IS_SPACE(duration))				\
			duration += (amount);			\
		else if (IS_PULSE(duration))			\
			duration -= (amount);			\
	} while (0)

#define TO_UNITS(duration, unit_len)				\
	((int)((duration) > 0 ?					\
		DIV_ROUND_CLOSEST(abs((duration)), (unit_len)) :\
		-DIV_ROUND_CLOSEST(abs((duration)), (unit_len))))
#define TO_US(duration)		((int)TO_UNITS(duration, 1000))

#endif /* _IR_CORE */