/*
 * Copyright (C) 2020 Inria
 *
 * This file is subject to the terms and conditions of the GNU Lesser
 * General Public License v2.1. See the file LICENSE in the top level
 * directory for more details.
 */

/**
 * @ingroup     cpu_nrf52
 * @{
 *
 * @file
 * @brief       Shared IRQ handling between SPI and TWI peripherals on the nRF52
 *              devices
 *
 *              I2C is called TWI (Two Wire Interface) in the datasheets from Nordic
 *
 * @author      Koen Zandberg <koen@bergzand.net>
 *
 * @}
 */

#include <assert.h>

#include "cpu.h"
#include "mutex.h"
#include "periph_cpu.h"

#if NRF_SPIM0_BASE != NRF_TWIM0_BASE
#define ISR_SPIM0   isr_spi0

#if defined(NRF_SPIM1)
#define ISR_SPIM1   isr_spi1_twi0
#else
#define ISR_SPIM1   isr_twi0
#endif

/* nRF52832 and nRF52840 ISR names */
#else

#define ISR_SPIM0   isr_spi0_twi0
#define ISR_SPIM1   isr_spi1_twi1

#endif

/**
 * The vendor file is weird here. nRF52805 is the only other MCU
 * that has only 1 SPI and separate 1 TWI interface, but define
 * SPIM_COUNT = 2, which is in line with how it is used here.
 * nRF52810 has the same set of SPI/TWI peripherals, but defines
 * SPIM_COUNT = 1 which is more logical.
 * Just re-define it to work around this inconsistency.
 */
#ifdef CPU_MODEL_NRF52810XXAA
#undef SPIM_COUNT
#define SPIM_COUNT 2
#endif

static shared_irq_cb_t _irq[SPIM_COUNT];
static void *_irq_arg[SPIM_COUNT];

static mutex_t _locks[SPIM_COUNT];

/* I2C and SPI share peripheral addresses */
static size_t _spi_dev2num(void *dev)
{
    if (dev == NRF_SPIM0) {
        return 0;
    }
#ifdef NRF_SPIM1
    else if (dev == NRF_SPIM1) {
        return 1;
    }
#endif
#ifdef NRF_SPIM2
    else if (dev == NRF_SPIM2) {
        return 2;
    }
#endif /* NRF_SPIM2 */
#ifdef NRF_SPIM3
    else if (dev == NRF_SPIM3) {
        return 3;
    }
#endif /* NRF_SPIM3 */
    else {
        assert(false);
        return 0;
    }
}

static inline size_t _i2c_dev2num(void *dev)
{
    if (NRF_SPIM0_BASE == NRF_TWIM0_BASE) {
        return _spi_dev2num(dev);
    } else {
        assert(!IS_ACTIVE(NRF_TWIM1_BASE));
        /* if they are not equal (nrf528105/10/11)
           TWI0 is mapped to SPI1 */
        return 1;
    }
}

static const IRQn_Type _isr[] = {

#if NRF_SPIM0_BASE == NRF_TWIM0_BASE
    SPIM0_SPIS0_TWIM0_TWIS0_SPI0_TWI0_IRQn,
    SPIM1_SPIS1_TWIM1_TWIS1_SPI1_TWI1_IRQn,
#else
    SPIM0_SPIS0_SPI0_IRQn,
#if defined(NRF_SPIM1)
    TWIM0_TWIS0_TWI0_SPIM1_SPIS1_SPI1_IRQn,
#else
    TWIM0_TWIS0_TWI0_IRQn,
#endif
#endif

#ifdef NRF_SPIM2
    SPIM2_SPIS2_SPI2_IRQn,
#endif
#ifdef NRF_SPIM3
    SPIM3_IRQn,
#endif /* CPU_MODEL_NRF52840XXAA */
};

void shared_irq_register_spi(NRF_SPIM_Type *bus,
                              shared_irq_cb_t cb, void *arg)
{
    size_t num = _spi_dev2num(bus);

    _irq[num] = cb;
    _irq_arg[num] = arg;
    NVIC_EnableIRQ(_isr[num]);
}

void shared_irq_register_i2c(NRF_TWIM_Type *bus,
                              shared_irq_cb_t cb, void *arg)
{
    size_t num = _i2c_dev2num(bus);

    _irq[num] = cb;
    _irq_arg[num] = arg;

    NVIC_EnableIRQ(_isr[num]);
}

void nrf5x_i2c_acquire(NRF_TWIM_Type *bus,
                       shared_irq_cb_t cb, void *arg)
{
    size_t num = _i2c_dev2num(bus);
    mutex_lock(&_locks[num]);
    _irq[num] = cb;
    _irq_arg[num] = arg;
}

void nrf5x_spi_acquire(NRF_SPIM_Type *bus,
                       shared_irq_cb_t cb, void *arg)
{
    size_t num = _spi_dev2num(bus);
    mutex_lock(&_locks[num]);
    _irq[num] = cb;
    _irq_arg[num] = arg;
}

void nrf5x_i2c_release(NRF_TWIM_Type *bus)
{
    size_t num = _i2c_dev2num(bus);
    mutex_unlock(&_locks[num]);
}

void nrf5x_spi_release(NRF_SPIM_Type *bus)
{
    size_t num = _spi_dev2num(bus);
    mutex_unlock(&_locks[num]);
}

void ISR_SPIM0(void)
{
    _irq[0](_irq_arg[0]);
    cortexm_isr_end();
}

void ISR_SPIM1(void)
{
    _irq[1](_irq_arg[1]);
    cortexm_isr_end();
}

#ifdef NRF_SPIM2
void isr_spi2(void)
{
    _irq[2](_irq_arg[2]);
    cortexm_isr_end();
}
#endif

#ifdef NRF_SPIM3
void isr_spi3(void)
{
    _irq[3](_irq_arg[3]);
    cortexm_isr_end();
}
#endif /* NRF_SPIM3 */