/******************************************************************************
 *
 * Copyright (C) 2022-2023 Maxim Integrated Products, Inc. (now owned by 
 * Analog Devices, Inc.),
 * Copyright (C) 2023-2024 Analog Devices, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 ******************************************************************************/

#include <stddef.h>
#include <string.h>
#include "mxc_assert.h"
#include "mxc_pins.h"
#include "mxc_lock.h"
#include "mxc_delay.h"
#include "mxc_device.h"
#include "mxc_errors.h"
#include "nvic_table.h"
#include "skbd.h"
#include "skbd_reva.h"

/* ***** SKBD context info ***** */
static mxc_skbd_reva_req_t mxc_skbd_req;

#ifndef __riscv
static void SKBD_RevA_IRQHandler(void)
{
    if (mxc_skbd_req.irq_handler) {
        mxc_skbd_req.irq_handler();
    }

    /* Acknowledge interrupt at platform level */
    NVIC_ClearPendingIRQ(SKB_IRQn);
}
#endif

int MXC_SKBD_RevA_PreInit(void)
{
    mxc_skbd_req.first_init = 0;

#ifndef __riscv
    NVIC_ClearPendingIRQ(SKB_IRQn);
    /* Attach vector */
    MXC_NVIC_SetVector(SKB_IRQn, SKBD_RevA_IRQHandler);
#endif

    return E_NO_ERROR;
}

int MXC_SKBD_RevA_Init(mxc_skbd_reva_regs_t *skbd, mxc_skbd_config_t config)
{
    int result = E_NO_ERROR;

    if (!mxc_skbd_req.first_init) {
        unsigned int temp;
        /* Number of output pins */
        unsigned int outputs = 0;

        /* Check for the I/O pin overlaps */
        if (config.outputs & config.inputs) {
            return MXC_SKBD_REVA_ERR_INVALID_PIN_CONFIGURATION;
        }

        /* I/O pin direction selection for the SKBD pins */
        /* Configure SKBD output pins */
        skbd->ctrl0 |= config.outputs;
        /* Configure SKBD input pins */
        skbd->ctrl0 &= ~(config.inputs);
        /* Memset like procedure */
        memset((unsigned char *)&mxc_skbd_req, 0x00, sizeof(mxc_skbd_req));
        /* Count the number of output SKBD lines */
        temp = config.outputs;

        while (temp) {
            temp &= (temp - 1);
            outputs++;
        }

        /* Configure the SKBD  */
        skbd->ctrl1 = (config.reg_erase << MXC_F_SKBD_REVA_CTRL1_CLEAR_POS) |
                      MXC_F_SKBD_REVA_CTRL1_AUTOEN // ->ctrl1[0]
                      | MXC_F_SKBD_REVA_CTRL1_CLEAR // ->ctrl1[1]
                      | MXC_F_SKBD_REVA_CTRL1_OUTNB //ctrl1[11:8]
                      | ((config.debounce << MXC_F_SKBD_REVA_CTRL1_DBTM_POS) &
                         MXC_F_SKBD_REVA_CTRL1_DBTM); //ctrl1[15:13]

        while (!(skbd->sr & MXC_F_SKBD_REVA_SR_BUSY)) {}

        /* Setup IRQ */
        if (config.irq_handler) {
            mxc_skbd_req.irq_handler = config.irq_handler;
        }

        /* To be done once only */
        mxc_skbd_req.first_init = 1;
        mxc_skbd_req.state = MXC_SKBD_REVA_STATE_INITIALIZED;
    } else {
        result = MXC_SKBD_REVA_ERR_ALREAD_INITIALIZED;
    }

    return result;
}

int MXC_SKBD_RevA_EnableInterruptEvents(mxc_skbd_reva_regs_t *skbd, unsigned int events)
{
    int result = E_NO_ERROR;

    if (MXC_SKBD_REVA_STATE_INITIALIZED != mxc_skbd_req.state) {
        result = MXC_SKBD_REVA_ERR_NOT_INITIALIZED;
    } else {
        events &=
            (MXC_SKBD_REVA_EVENT_PUSH | MXC_SKBD_REVA_EVENT_RELEASE | MXC_SKBD_REVA_EVENT_OVERRUN);
        skbd->ier |= events;
    }

    return result;
}

extern inline int MXC_SKBD_RevA_DisableInterruptEvents(mxc_skbd_reva_regs_t *skbd,
                                                       unsigned int events)
{
    events &=
        (MXC_SKBD_REVA_EVENT_PUSH | MXC_SKBD_REVA_EVENT_RELEASE | MXC_SKBD_REVA_EVENT_OVERRUN);
    skbd->ier &= ~events;
    return E_NO_ERROR;
}

extern inline int MXC_SKBD_RevA_ClearInterruptStatus(mxc_skbd_reva_regs_t *skbd,
                                                     unsigned int status)
{
    status &= (MXC_SKBD_REVA_INTERRUPT_STATUS_PUSHIS | MXC_SKBD_REVA_INTERRUPT_STATUS_RELEASEIS |
               MXC_SKBD_REVA_INTERRUPT_STATUS_OVERIS);
    skbd->isr &= ~status;
    return E_NO_ERROR;
}

extern inline int MXC_SKBD_RevA_InterruptStatus(mxc_skbd_reva_regs_t *skbd, unsigned int *status)
{
    if (status == NULL) {
        return E_NULL_PTR;
    }

    *status = skbd->isr;
    return E_NO_ERROR;
}

int MXC_SKBD_RevA_ReadKeys(mxc_skbd_reva_regs_t *skbd, mxc_skbd_reva_keys_t *keys)
{
    volatile uint16_t *key;
    volatile unsigned int i = 0;
    volatile unsigned int temp;
    volatile unsigned int *key_reg;

    if (keys == NULL) {
        return E_NULL_PTR;
    }

    key = (uint16_t *)&keys->key0_reva;
    key_reg = (unsigned int *)&skbd->evt[0];

    for (i = 0; i < MXC_SKBD_REVA_TOTAL_KEY_REGS; i++) {
        if (!(skbd->ctrl1 & MXC_F_SKBD_REVA_CTRL1_CLEAR) &&
            (skbd->ier & MXC_F_SKBD_REVA_IER_PUSHIE)) {
            if (!(*key_reg & (MXC_F_SKBD_REVA_EVT_PUSH | MXC_F_SKBD_REVA_EVT_READ))) {
                *key++ = ((*key_reg & MXC_F_SKBD_REVA_EVT_IOIN) |
                          ((*key_reg & MXC_F_SKBD_REVA_EVT_IOOUT) >> 1));
            }
        } else if (!(skbd->ctrl1 & MXC_F_SKBD_REVA_CTRL1_CLEAR) &&
                   (skbd->ier & MXC_F_SKBD_REVA_IER_RELEASEIE)) {
            temp = *key_reg;

            if ((temp & MXC_F_SKBD_REVA_EVT_PUSH) && !(temp & MXC_F_SKBD_REVA_EVT_READ)) {
                *key++ = ((*key_reg & MXC_F_SKBD_REVA_EVT_IOIN) |
                          ((*key_reg & MXC_F_SKBD_REVA_EVT_IOOUT) >> 1));
            }
        } else {
            temp = *key_reg;

            if (!(temp & MXC_F_SKBD_REVA_EVT_READ)) {
                *key++ =
                    ((temp & MXC_F_SKBD_REVA_EVT_IOIN) | ((temp & MXC_F_SKBD_REVA_EVT_IOOUT) >> 1));
            }
        }

        key_reg++;
    }

    return E_NO_ERROR;
}

int MXC_SKBD_RevA_Close(void)
{
#ifndef __riscv
    NVIC_DisableIRQ(SKB_IRQn);
#endif

    mxc_skbd_req.state = MXC_SKBD_REVA_STATE_CLOSED;
    mxc_skbd_req.first_init = 0;
    return E_NO_ERROR;
}