linux-imx

// SPDX-License-Identifier: GPL-2.0-only

/* ir-sony-decoder.c - handle Sony IR Pulse/Space protocol

 *

 * Copyright (C) 2010 by David Härdeman <david@hardeman.nu>

 */

​

#include <linux/bitrev.h>

#include <linux/module.h>

#include "rc-core-priv.h"

​

#define SONY_UNIT       600000 /* ns */

#define SONY_HEADER_PULSE   (4 * SONY_UNIT)

#define SONY_HEADER_SPACE   (1 * SONY_UNIT)

#define SONY_BIT_0_PULSE    (1 * SONY_UNIT)

#define SONY_BIT_1_PULSE    (2 * SONY_UNIT)

#define SONY_BIT_SPACE      (1 * SONY_UNIT)

#define SONY_TRAILER_SPACE  (10 * SONY_UNIT) /* minimum */

​

enum sony_state {

    STATE_INACTIVE,

    STATE_HEADER_SPACE,

    STATE_BIT_PULSE,

    STATE_BIT_SPACE,

    STATE_FINISHED,

};

​

/**

 * ir_sony_decode() - Decode one Sony pulse or space

 * @dev:    the struct rc_dev descriptor of the device

 * @ev:         the struct ir_raw_event descriptor of the pulse/space

 *

 * This function returns -EINVAL if the pulse violates the state machine

 */

static int ir_sony_decode(struct rc_dev *dev, struct ir_raw_event ev)

{

    struct sony_dec *data = &dev->raw->sony;

    enum rc_proto protocol;

    u32 scancode;

    u8 device, subdevice, function;

​

    if (!is_timing_event(ev)) {

        if (ev.reset)

            data->state = STATE_INACTIVE;

        return 0;

    }

​

    if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2))

        goto out;

​

    dev_dbg(&dev->dev, "Sony decode started at state %d (%uus %s)\n",

        data->state, TO_US(ev.duration), TO_STR(ev.pulse));

​

    switch (data->state) {

​

    case STATE_INACTIVE:

        if (!ev.pulse)

            break;

​

        if (!eq_margin(ev.duration, SONY_HEADER_PULSE, SONY_UNIT / 2))

            break;

​

        data->count = 0;

        data->state = STATE_HEADER_SPACE;

        return 0;

​

    case STATE_HEADER_SPACE:

        if (ev.pulse)

            break;

​

        if (!eq_margin(ev.duration, SONY_HEADER_SPACE, SONY_UNIT / 2))

            break;

​

        data->state = STATE_BIT_PULSE;

        return 0;

​

    case STATE_BIT_PULSE:

        if (!ev.pulse)

            break;

​

        data->bits <<= 1;

        if (eq_margin(ev.duration, SONY_BIT_1_PULSE, SONY_UNIT / 2))

            data->bits |= 1;

        else if (!eq_margin(ev.duration, SONY_BIT_0_PULSE, SONY_UNIT / 2))

            break;

​

        data->count++;

        data->state = STATE_BIT_SPACE;

        return 0;

​

    case STATE_BIT_SPACE:

        if (ev.pulse)

            break;