/**
 ******************************************************************************
 *
 * @addtogroup PIOS PIOS Core hardware abstraction layer
 * @{
 * @addtogroup PIOS_EXTI External Interrupt Handlers
 * @brief External interrupt handler functions
 * @{
 *
 * @file       pios_exti.c
 * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
 * @brief      External Interrupt Handlers
 * @see        The GNU Public License (GPL) Version 3
 *
 *****************************************************************************/
/*
 * 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 3 of the License, or
 * (at your option) any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "pios.h"

#ifdef PIOS_INCLUDE_EXTI

/* Map EXTI line to full config */
#define EXTI_MAX_LINES    16
#define PIOS_EXTI_INVALID 0xFF
static uint8_t pios_exti_line_to_cfg_map[EXTI_MAX_LINES] = {
    [0 ... EXTI_MAX_LINES - 1] = PIOS_EXTI_INVALID,
};

/* Table of exti configs registered at compile time */
extern struct pios_exti_cfg __start__exti __attribute__((weak));
extern struct pios_exti_cfg __stop__exti  __attribute__((weak));

static uint8_t PIOS_EXTI_line_to_index(uint32_t line)
{
    switch (line) {
    case EXTI_Line0: return 0;

    case EXTI_Line1: return 1;

    case EXTI_Line2: return 2;

    case EXTI_Line3: return 3;

    case EXTI_Line4: return 4;

    case EXTI_Line5: return 5;

    case EXTI_Line6: return 6;

    case EXTI_Line7: return 7;

    case EXTI_Line8: return 8;

    case EXTI_Line9: return 9;

    case EXTI_Line10: return 10;

    case EXTI_Line11: return 11;

    case EXTI_Line12: return 12;

    case EXTI_Line13: return 13;

    case EXTI_Line14: return 14;

    case EXTI_Line15: return 15;
    }

    PIOS_Assert(0);
    return 0xFF;
}

uint8_t PIOS_EXTI_gpio_port_to_exti_source_port(GPIO_TypeDef *gpio_port)
{
    switch ((uint32_t)gpio_port) {
    case (uint32_t)GPIOA: return EXTI_PortSourceGPIOA;

    case (uint32_t)GPIOB: return EXTI_PortSourceGPIOB;

    case (uint32_t)GPIOC: return EXTI_PortSourceGPIOC;

    case (uint32_t)GPIOD: return EXTI_PortSourceGPIOD;

    case (uint32_t)GPIOE: return EXTI_PortSourceGPIOE;

    case (uint32_t)GPIOF: return EXTI_PortSourceGPIOF;
    }

    PIOS_Assert(0);
    return 0xFF;
}

uint8_t PIOS_EXTI_gpio_pin_to_exti_source_pin(uint32_t gpio_pin)
{
    switch ((uint32_t)gpio_pin) {
    case GPIO_Pin_0: return GPIO_PinSource0;

    case GPIO_Pin_1: return GPIO_PinSource1;

    case GPIO_Pin_2: return GPIO_PinSource2;

    case GPIO_Pin_3: return GPIO_PinSource3;

    case GPIO_Pin_4: return GPIO_PinSource4;

    case GPIO_Pin_5: return GPIO_PinSource5;

    case GPIO_Pin_6: return GPIO_PinSource6;

    case GPIO_Pin_7: return GPIO_PinSource7;

    case GPIO_Pin_8: return GPIO_PinSource8;

    case GPIO_Pin_9: return GPIO_PinSource9;

    case GPIO_Pin_10: return GPIO_PinSource10;

    case GPIO_Pin_11: return GPIO_PinSource11;

    case GPIO_Pin_12: return GPIO_PinSource12;

    case GPIO_Pin_13: return GPIO_PinSource13;

    case GPIO_Pin_14: return GPIO_PinSource14;

    case GPIO_Pin_15: return GPIO_PinSource15;
    }

    PIOS_Assert(0);
    return 0xFF;
}

int32_t PIOS_EXTI_Init(const struct pios_exti_cfg *cfg)
{
    PIOS_Assert(cfg);
    PIOS_Assert(&__start__exti);
    PIOS_Assert(cfg >= &__start__exti);
    PIOS_Assert(cfg < &__stop__exti);

    uint8_t cfg_index  = cfg - &__start__exti;

    /* Connect this config to the requested vector */
    uint8_t line_index = PIOS_EXTI_line_to_index(cfg->line);

    if (pios_exti_line_to_cfg_map[line_index] != PIOS_EXTI_INVALID) {
        /* Someone else already has this mapped */
        goto out_fail;
    }

    /* Bind the config to the exti line */
    pios_exti_line_to_cfg_map[line_index] = cfg_index;

    /* Initialize the GPIO pin */
    GPIO_Init(cfg->pin.gpio, (GPIO_InitTypeDef *)&cfg->pin.init);

    /* Set up the EXTI interrupt source */
    uint8_t exti_source_port = PIOS_EXTI_gpio_port_to_exti_source_port(cfg->pin.gpio);
    uint8_t exti_source_pin  = PIOS_EXTI_gpio_pin_to_exti_source_pin(cfg->pin.init.GPIO_Pin);
    SYSCFG_EXTILineConfig(exti_source_port, exti_source_pin);
    EXTI_Init((EXTI_InitTypeDef *)&cfg->exti.init);

    /* Enable the interrupt channel */
    NVIC_Init((NVIC_InitTypeDef *)&cfg->irq.init);

    return 0;

out_fail:
    return -1;
}

static bool PIOS_EXTI_generic_irq_handler(uint8_t line_index)
{
    uint8_t cfg_index = pios_exti_line_to_cfg_map[line_index];

    PIOS_Assert(&__start__exti);

    if (cfg_index > NELEMENTS(pios_exti_line_to_cfg_map) ||
        cfg_index == PIOS_EXTI_INVALID) {
        /* Unconfigured interrupt just fired! */
        return false;
    }

    struct pios_exti_cfg *cfg = &__start__exti + cfg_index;
    return cfg->vector();
}

/* Bind Interrupt Handlers */

#ifdef PIOS_INCLUDE_FREERTOS
#define PIOS_EXTI_HANDLE_LINE(line, woken)                      \
    if (EXTI_GetITStatus(EXTI_Line##line) != RESET) {       \
        EXTI_ClearITPendingBit(EXTI_Line##line);        \
        woken = PIOS_EXTI_generic_irq_handler(line) ? pdTRUE : woken; \
    }
#else
#define PIOS_EXTI_HANDLE_LINE(line, woken)                      \
    if (EXTI_GetITStatus(EXTI_Line##line) != RESET) {       \
        EXTI_ClearITPendingBit(EXTI_Line##line);        \
        PIOS_EXTI_generic_irq_handler(line);            \
    }
#endif

static void PIOS_EXTI_0_1_irq_handler(void)
{
#ifdef PIOS_INCLUDE_FREERTOS
    portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
#else
    bool xHigherPriorityTaskWoken;
#endif
    PIOS_EXTI_HANDLE_LINE(0, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(1, xHigherPriorityTaskWoken);
#ifdef PIOS_INCLUDE_FREERTOS
    portEND_SWITCHING_ISR(xHigherPriorityTaskWoken);
#endif
}
void EXTI0_1_IRQHandler(void) __attribute__((alias("PIOS_EXTI_0_1_irq_handler")));


static void PIOS_EXTI_2_3_irq_handler(void)
{
#ifdef PIOS_INCLUDE_FREERTOS
    portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
#else
    bool xHigherPriorityTaskWoken;
#endif
    PIOS_EXTI_HANDLE_LINE(2, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(3, xHigherPriorityTaskWoken);
#ifdef PIOS_INCLUDE_FREERTOS
    portEND_SWITCHING_ISR(xHigherPriorityTaskWoken);
#endif
}
void EXTI2_3_IRQHandler(void) __attribute__((alias("PIOS_EXTI_2_3_irq_handler")));


static void PIOS_EXTI4_15_irq_handler(void)
{
#ifdef PIOS_INCLUDE_FREERTOS
    portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
#else
    bool xHigherPriorityTaskWoken;
#endif
    PIOS_EXTI_HANDLE_LINE(4, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(5, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(6, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(7, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(8, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(9, xHigherPriorityTaskWoken);

    PIOS_EXTI_HANDLE_LINE(10, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(11, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(12, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(13, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(14, xHigherPriorityTaskWoken);
    PIOS_EXTI_HANDLE_LINE(15, xHigherPriorityTaskWoken);
#ifdef PIOS_INCLUDE_FREERTOS
    portEND_SWITCHING_ISR(xHigherPriorityTaskWoken);
#endif
}
void EXTI4_15_IRQHandler(void) __attribute__((alias("PIOS_EXTI4_15_irq_handler")));

#endif /* PIOS_INCLUDE_EXTI */

/**
 * @}
 * @}
 */