/*
 * ImgTec IR Hardware Decoder found in PowerDown Controller.
 *
 * Copyright 2010-2014 Imagination Technologies Ltd.
 *
 * 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.
 */

#ifndef _IMG_IR_HW_H_
#define _IMG_IR_HW_H_

#include <linux/kernel.h>
#include <media/rc-core.h>

/* constants */

#define IMG_IR_CODETYPE_PULSELEN        0x0     /* Sony */
#define IMG_IR_CODETYPE_PULSEDIST       0x1     /* NEC, Toshiba, Micom, Sharp */
#define IMG_IR_CODETYPE_BIPHASE         0x2     /* RC-5/6 */
#define IMG_IR_CODETYPE_2BITPULSEPOS    0x3     /* RC-MM */


/* Timing information */

/**
 * struct img_ir_control - Decoder control settings
 * @decoden:    Primary decoder enable
 * @code_type:  Decode type (see IMG_IR_CODETYPE_*)
 * @hdrtog:     Detect header toggle symbol after leader symbol
 * @ldrdec:     Don't discard leader if maximum width reached
 * @decodinpol: Decoder input polarity (1=active high)
 * @bitorien:   Bit orientation (1=MSB first)
 * @d1validsel: Decoder 2 takes over if it detects valid data
 * @bitinv:     Bit inversion switch (1=don't invert)
 * @decodend2:  Secondary decoder enable (no leader symbol)
 * @bitoriend2: Bit orientation (1=MSB first)
 * @bitinvd2:   Secondary decoder bit inversion switch (1=don't invert)
 */
struct img_ir_control {
        unsigned decoden:1;
        unsigned code_type:2;
        unsigned hdrtog:1;
        unsigned ldrdec:1;
        unsigned decodinpol:1;
        unsigned bitorien:1;
        unsigned d1validsel:1;
        unsigned bitinv:1;
        unsigned decodend2:1;
        unsigned bitoriend2:1;
        unsigned bitinvd2:1;
};

/**
 * struct img_ir_timing_range - range of timing values
 * @min:        Minimum timing value
 * @max:        Maximum timing value (if < @min, this will be set to @min during
 *              preprocessing step, so it is normally not explicitly initialised
 *              and is taken care of by the tolerance)
 */
struct img_ir_timing_range {
        u16 min;
        u16 max;
};

/**
 * struct img_ir_symbol_timing - timing data for a symbol
 * @pulse:      Timing range for the length of the pulse in this symbol
 * @space:      Timing range for the length of the space in this symbol
 */
struct img_ir_symbol_timing {
        struct img_ir_timing_range pulse;
        struct img_ir_timing_range space;
};

/**
 * struct img_ir_free_timing - timing data for free time symbol
 * @minlen:     Minimum number of bits of data
 * @maxlen:     Maximum number of bits of data
 * @ft_min:     Minimum free time after message
 */
struct img_ir_free_timing {
        /* measured in bits */
        u8 minlen;
        u8 maxlen;
        u16 ft_min;
};

/**
 * struct img_ir_timings - Timing values.
 * @ldr:        Leader symbol timing data
 * @s00:        Zero symbol timing data for primary decoder
 * @s01:        One symbol timing data for primary decoder
 * @s10:        Zero symbol timing data for secondary (no leader symbol) decoder
 * @s11:        One symbol timing data for secondary (no leader symbol) decoder
 * @ft:         Free time symbol timing data
 */
struct img_ir_timings {
        struct img_ir_symbol_timing ldr, s00, s01, s10, s11;
        struct img_ir_free_timing ft;
};

/**
 * struct img_ir_filter - Filter IR events.
 * @data:       Data to match.
 * @mask:       Mask of bits to compare.
 * @minlen:     Additional minimum number of bits.
 * @maxlen:     Additional maximum number of bits.
 */
struct img_ir_filter {
        u64 data;
        u64 mask;
        u8 minlen;
        u8 maxlen;
};

/**
 * struct img_ir_timing_regvals - Calculated timing register values.
 * @ldr:        Leader symbol timing register value
 * @s00:        Zero symbol timing register value for primary decoder
 * @s01:        One symbol timing register value for primary decoder
 * @s10:        Zero symbol timing register value for secondary decoder
 * @s11:        One symbol timing register value for secondary decoder
 * @ft:         Free time symbol timing register value
 */
struct img_ir_timing_regvals {
        u32 ldr, s00, s01, s10, s11, ft;
};

#define IMG_IR_SCANCODE         0       /* new scancode */
#define IMG_IR_REPEATCODE       1       /* repeat the previous code */

/**
 * struct img_ir_scancode_req - Scancode request data.
 * @protocol:   Protocol code of received message (defaults to
 *              RC_PROTO_UNKNOWN).
 * @scancode:   Scan code of received message (must be written by
 *              handler if IMG_IR_SCANCODE is returned).
 * @toggle:     Toggle bit (defaults to 0).
 */
struct img_ir_scancode_req {
        enum rc_proto protocol;
        u32 scancode;
        u8 toggle;
};

/**
 * struct img_ir_decoder - Decoder settings for an IR protocol.
 * @type:       Protocol types bitmap.
 * @tolerance:  Timing tolerance as a percentage (default 10%).
 * @unit:       Unit of timings in nanoseconds (default 1 us).
 * @timings:    Primary timings
 * @rtimings:   Additional override timings while waiting for repeats.
 * @repeat:     Maximum repeat interval (always in milliseconds).
 * @control:    Control flags.
 *
 * @scancode:   Pointer to function to convert the IR data into a scancode (it
 *              must be safe to execute in interrupt context).
 *              Returns IMG_IR_SCANCODE to emit new scancode.
 *              Returns IMG_IR_REPEATCODE to repeat previous code.
 *              Returns -errno (e.g. -EINVAL) on error.
 * @filter:     Pointer to function to convert scancode filter to raw hardware
 *              filter. The minlen and maxlen fields will have been initialised
 *              to the maximum range.
 */
struct img_ir_decoder {
        /* core description */
        u64                             type;
        unsigned int                    tolerance;
        unsigned int                    unit;
        struct img_ir_timings           timings;
        struct img_ir_timings           rtimings;
        unsigned int                    repeat;
        struct img_ir_control           control;

        /* scancode logic */
        int (*scancode)(int len, u64 raw, u64 enabled_protocols,
                        struct img_ir_scancode_req *request);
        int (*filter)(const struct rc_scancode_filter *in,
                      struct img_ir_filter *out, u64 protocols);
};

extern struct img_ir_decoder img_ir_nec;
extern struct img_ir_decoder img_ir_jvc;
extern struct img_ir_decoder img_ir_sony;
extern struct img_ir_decoder img_ir_sharp;
extern struct img_ir_decoder img_ir_sanyo;
extern struct img_ir_decoder img_ir_rc5;
extern struct img_ir_decoder img_ir_rc6;

/**
 * struct img_ir_reg_timings - Reg values for decoder timings at clock rate.
 * @ctrl:       Processed control register value.
 * @timings:    Processed primary timings.
 * @rtimings:   Processed repeat timings.
 */
struct img_ir_reg_timings {
        u32                             ctrl;
        struct img_ir_timing_regvals    timings;
        struct img_ir_timing_regvals    rtimings;
};

struct img_ir_priv;

#ifdef CONFIG_IR_IMG_HW

enum img_ir_mode {
        IMG_IR_M_NORMAL,
        IMG_IR_M_REPEATING,
#ifdef CONFIG_PM_SLEEP
        IMG_IR_M_WAKE,
#endif
};

/**
 * struct img_ir_priv_hw - Private driver data for hardware decoder.
 * @ct_quirks:          Quirk bits for each code type.
 * @rdev:               Remote control device
 * @clk_nb:             Notifier block for clock notify events.
 * @end_timer:          Timer until repeat timeout.
 * @suspend_timer:      Timer to re-enable protocol.
 * @decoder:            Current decoder settings.
 * @enabled_protocols:  Currently enabled protocols.
 * @clk_hz:             Current core clock rate in Hz.
 * @reg_timings:        Timing reg values for decoder at clock rate.
 * @flags:              IMG_IR_F_*.
 * @filters:            HW filters (derived from scancode filters).
 * @mode:               Current decode mode.
 * @stopping:           Indicates that decoder is being taken down and timers
 *                      should not be restarted.
 * @suspend_irqen:      Saved IRQ enable mask over suspend.
 * @quirk_suspend_irq:  Saved IRQ enable mask over quirk suspend timer.
 */
struct img_ir_priv_hw {
        unsigned int                    ct_quirks[4];
        struct rc_dev                   *rdev;
        struct notifier_block           clk_nb;
        struct timer_list               end_timer;
        struct timer_list               suspend_timer;
        const struct img_ir_decoder     *decoder;
        u64                             enabled_protocols;
        unsigned long                   clk_hz;
        struct img_ir_reg_timings       reg_timings;
        unsigned int                    flags;
        struct img_ir_filter            filters[RC_FILTER_MAX];

        enum img_ir_mode                mode;
        bool                            stopping;
        u32                             suspend_irqen;
        u32                             quirk_suspend_irq;
};

static inline bool img_ir_hw_enabled(struct img_ir_priv_hw *hw)
{
        return hw->rdev;
};

void img_ir_isr_hw(struct img_ir_priv *priv, u32 irq_status);
void img_ir_setup_hw(struct img_ir_priv *priv);
int img_ir_probe_hw(struct img_ir_priv *priv);
void img_ir_remove_hw(struct img_ir_priv *priv);

#ifdef CONFIG_PM_SLEEP
int img_ir_suspend(struct device *dev);
int img_ir_resume(struct device *dev);
#else
#define img_ir_suspend NULL
#define img_ir_resume NULL
#endif

#else

struct img_ir_priv_hw {
};

static inline bool img_ir_hw_enabled(struct img_ir_priv_hw *hw)
{
        return false;
};
static inline void img_ir_isr_hw(struct img_ir_priv *priv, u32 irq_status)
{
}
static inline void img_ir_setup_hw(struct img_ir_priv *priv)
{
}
static inline int img_ir_probe_hw(struct img_ir_priv *priv)
{
        return -ENODEV;
}
static inline void img_ir_remove_hw(struct img_ir_priv *priv)
{
}

#define img_ir_suspend NULL
#define img_ir_resume NULL

#endif /* CONFIG_IR_IMG_HW */

#endif /* _IMG_IR_HW_H_ */