/*
 * Remote Controller core header
 *
 * Copyright (C) 2009-2010 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.
 */

#ifndef _RC_CORE
#define _RC_CORE

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

extern int rc_core_debug;
#define IR_dprintk(level, fmt, ...)                             \
do {                                                            \
        if (rc_core_debug >= level)                             \
                printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__);  \
} while (0)

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 */
};

/**
 * struct rc_scancode_filter - Filter scan codes.
 * @data:       Scancode data to match.
 * @mask:       Mask of bits of scancode to compare.
 */
struct rc_scancode_filter {
        u32 data;
        u32 mask;
};

/**
 * enum rc_filter_type - Filter type constants.
 * @RC_FILTER_NORMAL:   Filter for normal operation.
 * @RC_FILTER_WAKEUP:   Filter for waking from suspend.
 * @RC_FILTER_MAX:      Number of filter types.
 */
enum rc_filter_type {
        RC_FILTER_NORMAL = 0,
        RC_FILTER_WAKEUP,

        RC_FILTER_MAX
};

/**
 * struct rc_dev - represents a remote control device
 * @dev: driver model's view of this device
 * @initialized: 1 if the device init has completed, 0 otherwise
 * @sysfs_groups: sysfs attribute groups
 * @input_name: name of the input child device
 * @input_phys: physical path to the input child device
 * @input_id: id of the input child device (struct input_id)
 * @driver_name: name of the hardware driver which registered this device
 * @map_name: name of the default keymap
 * @rc_map: current scan/key table
 * @lock: used to ensure we've filled in all protocol details before
 *      anyone can call show_protocols or store_protocols
 * @minor: unique minor remote control device number
 * @raw: additional data for raw pulse/space devices
 * @input_dev: the input child device used to communicate events to userspace
 * @driver_type: specifies if protocol decoding is done in hardware or software
 * @idle: used to keep track of RX state
 * @allowed_protocols: bitmask with the supported RC_BIT_* protocols
 * @enabled_protocols: bitmask with the enabled RC_BIT_* protocols
 * @allowed_wakeup_protocols: bitmask with the supported RC_BIT_* wakeup protocols
 * @enabled_wakeup_protocols: bitmask with the enabled RC_BIT_* wakeup protocols
 * @scancode_filter: scancode filter
 * @scancode_wakeup_filter: scancode wakeup filters
 * @scancode_mask: 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
 * @users: number of current users of the device
 * @priv: driver-specific data
 * @keylock: protects the remaining members of the struct
 * @keypressed: whether a key is currently pressed
 * @keyup_jiffies: time (in jiffies) when the current keypress should be released
 * @timer_keyup: timer for releasing a keypress
 * @last_keycode: keycode of last keypress
 * @last_protocol: protocol of last keypress
 * @last_scancode: scancode of last keypress
 * @last_toggle: toggle value of last command
 * @timeout: optional time after which device stops sending data
 * @min_timeout: minimum timeout supported by device
 * @max_timeout: maximum timeout supported by device
 * @rx_resolution : resolution (in ns) of input sampler
 * @tx_resolution: resolution (in ns) of output sampler
 * @change_protocol: allow changing the protocol used on hardware decoders
 * @change_wakeup_protocol: allow changing the protocol used for wakeup
 *      filtering
 * @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.
 * @s_tx_mask: set transmitter mask (for devices with multiple tx outputs)
 * @s_tx_carrier: set transmit carrier frequency
 * @s_tx_duty_cycle: set transmit duty cycle (0% - 100%)
 * @s_rx_carrier_range: inform driver about carrier it is expected to handle
 * @tx_ir: transmit IR
 * @s_idle: enable/disable hardware idle mode, upon which,
 *      device doesn't interrupt host until it sees IR pulses
 * @s_learning_mode: enable wide band receiver used for learning
 * @s_carrier_report: enable carrier reports
 * @s_filter: set the scancode filter
 * @s_wakeup_filter: set the wakeup scancode filter
 */
struct rc_dev {
        struct device                   dev;
        atomic_t                        initialized;
        const struct attribute_group    *sysfs_groups[5];
        const char                      *input_name;
        const char                      *input_phys;
        struct input_id                 input_id;
        char                            *driver_name;
        const char                      *map_name;
        struct rc_map                   rc_map;
        struct mutex                    lock;
        unsigned int                    minor;
        struct ir_raw_event_ctrl        *raw;
        struct input_dev                *input_dev;
        enum rc_driver_type             driver_type;
        bool                            idle;
        u64                             allowed_protocols;
        u64                             enabled_protocols;
        u64                             allowed_wakeup_protocols;
        u64                             enabled_wakeup_protocols;
        struct rc_scancode_filter       scancode_filter;
        struct rc_scancode_filter       scancode_wakeup_filter;
        u32                             scancode_mask;
        u32                             users;
        void                            *priv;
        spinlock_t                      keylock;
        bool                            keypressed;
        unsigned long                   keyup_jiffies;
        struct timer_list               timer_keyup;
        u32                             last_keycode;
        enum rc_type                    last_protocol;
        u32                             last_scancode;
        u8                              last_toggle;
        u32                             timeout;
        u32                             min_timeout;
        u32                             max_timeout;
        u32                             rx_resolution;
        u32                             tx_resolution;
        int                             (*change_protocol)(struct rc_dev *dev, u64 *rc_type);
        int                             (*change_wakeup_protocol)(struct rc_dev *dev, u64 *rc_type);
        int                             (*open)(struct rc_dev *dev);
        void                            (*close)(struct rc_dev *dev);
        int                             (*s_tx_mask)(struct rc_dev *dev, u32 mask);
        int                             (*s_tx_carrier)(struct rc_dev *dev, u32 carrier);
        int                             (*s_tx_duty_cycle)(struct rc_dev *dev, u32 duty_cycle);
        int                             (*s_rx_carrier_range)(struct rc_dev *dev, u32 min, u32 max);
        int                             (*tx_ir)(struct rc_dev *dev, unsigned *txbuf, unsigned n);
        void                            (*s_idle)(struct rc_dev *dev, bool enable);
        int                             (*s_learning_mode)(struct rc_dev *dev, int enable);
        int                             (*s_carrier_report) (struct rc_dev *dev, int enable);
        int                             (*s_filter)(struct rc_dev *dev,
                                                    struct rc_scancode_filter *filter);
        int                             (*s_wakeup_filter)(struct rc_dev *dev,
                                                           struct rc_scancode_filter *filter);
};

#define to_rc_dev(d) container_of(d, struct rc_dev, dev)

/*
 * From rc-main.c
 * Those functions can be used on any type of Remote Controller. They
 * basically creates an input_dev and properly reports the device as a
 * Remote Controller, at sys/class/rc.
 */

struct rc_dev *rc_allocate_device(void);
void rc_free_device(struct rc_dev *dev);
int rc_register_device(struct rc_dev *dev);
void rc_unregister_device(struct rc_dev *dev);

int rc_open(struct rc_dev *rdev);
void rc_close(struct rc_dev *rdev);

void rc_repeat(struct rc_dev *dev);
void rc_keydown(struct rc_dev *dev, enum rc_type protocol, u32 scancode, u8 toggle);
void rc_keydown_notimeout(struct rc_dev *dev, enum rc_type protocol, u32 scancode, u8 toggle);
void rc_keyup(struct rc_dev *dev);
u32 rc_g_keycode_from_table(struct rc_dev *dev, u32 scancode);

/*
 * From rc-raw.c
 * The Raw interface is specific to InfraRed. It may be a good idea to
 * split it later into a separate header.
 */

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

struct ir_raw_event {
        union {
                u32             duration;
                u32             carrier;
        };
        u8                      duty_cycle;

        unsigned                pulse:1;
        unsigned                reset:1;
        unsigned                timeout:1;
        unsigned                carrier_report:1;
};

#define DEFINE_IR_RAW_EVENT(event) struct ir_raw_event event = {}

static inline void init_ir_raw_event(struct ir_raw_event *ev)
{
        memset(ev, 0, sizeof(*ev));
}

#define IR_DEFAULT_TIMEOUT      MS_TO_NS(125)
#define IR_MAX_DURATION         500000000       /* 500 ms */
#define US_TO_NS(usec)          ((usec) * 1000)
#define MS_TO_US(msec)          ((msec) * 1000)
#define MS_TO_NS(msec)          ((msec) * 1000 * 1000)

void ir_raw_event_handle(struct rc_dev *dev);
int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev);
int ir_raw_event_store_edge(struct rc_dev *dev, enum raw_event_type type);
int ir_raw_event_store_with_filter(struct rc_dev *dev,
                                struct ir_raw_event *ev);
void ir_raw_event_set_idle(struct rc_dev *dev, bool idle);

static inline void ir_raw_event_reset(struct rc_dev *dev)
{
        struct ir_raw_event ev = { .reset = true };

        ir_raw_event_store(dev, &ev);
        ir_raw_event_handle(dev);
}

/* extract mask bits out of data and pack them into the result */
static inline u32 ir_extract_bits(u32 data, u32 mask)
{
        u32 vbit = 1, value = 0;

        do {
                if (mask & 1) {
                        if (data & 1)
                                value |= vbit;
                        vbit <<= 1;
                }
                data >>= 1;
        } while (mask >>= 1);

        return value;
}

#endif /* _RC_CORE */