/* Copyright 2018 Canaan 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 "fpioa.h"
#include "gpiohs.h"
#include "sysctl.h"
#include "utils.h"
#define GPIOHS_MAX_PINNO 32

volatile gpiohs_t *const gpiohs = (volatile gpiohs_t *)GPIOHS_BASE_ADDR;

typedef struct _gpiohs_pin_instance
{
    size_t pin;
    gpio_pin_edge_t edge;
    void (*callback)();
    plic_irq_callback_t gpiohs_callback;
    void *context;
} gpiohs_pin_instance_t;

static gpiohs_pin_instance_t pin_instance[32];

void gpiohs_set_drive_mode(uint8_t pin, gpio_drive_mode_t mode)
{
    configASSERT(pin < GPIOHS_MAX_PINNO);
    int io_number = fpioa_get_io_by_function(FUNC_GPIOHS0 + pin);
    configASSERT(io_number >= 0);

    fpioa_pull_t pull;
    uint32_t dir;

    switch(mode)
    {
        case GPIO_DM_INPUT:
            pull = FPIOA_PULL_NONE;
            dir = 0;
            break;
        case GPIO_DM_INPUT_PULL_DOWN:
            pull = FPIOA_PULL_DOWN;
            dir = 0;
            break;
        case GPIO_DM_INPUT_PULL_UP:
            pull = FPIOA_PULL_UP;
            dir = 0;
            break;
        case GPIO_DM_OUTPUT:
            pull = FPIOA_PULL_DOWN;
            dir = 1;
            break;
        default:
            configASSERT(!"GPIO drive mode is not supported.") break;
    }

    fpioa_set_io_pull(io_number, pull);
    volatile uint32_t *reg = dir ? gpiohs->output_en.u32 : gpiohs->input_en.u32;
    volatile uint32_t *reg_d = !dir ? gpiohs->output_en.u32 : gpiohs->input_en.u32;
    set_gpio_bit(reg_d, pin, 0);
    set_gpio_bit(reg, pin, 1);
}

gpio_pin_value_t gpiohs_get_pin(uint8_t pin)
{
    configASSERT(pin < GPIOHS_MAX_PINNO);
    return get_gpio_bit(gpiohs->input_val.u32, pin);
}

void gpiohs_set_pin(uint8_t pin, gpio_pin_value_t value)
{
    configASSERT(pin < GPIOHS_MAX_PINNO);
    set_gpio_bit(gpiohs->output_val.u32, pin, value);
}

void gpiohs_set_pin_edge(uint8_t pin, gpio_pin_edge_t edge)
{
    set_gpio_bit(gpiohs->rise_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->rise_ip.u32, pin, 1);

    set_gpio_bit(gpiohs->fall_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->fall_ip.u32, pin, 1);

    set_gpio_bit(gpiohs->low_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->low_ip.u32, pin, 1);

    set_gpio_bit(gpiohs->high_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->high_ip.u32, pin, 1);

    if(edge & GPIO_PE_FALLING)
    {
        set_gpio_bit(gpiohs->fall_ie.u32, pin, 1);
    } else
    {
        set_gpio_bit(gpiohs->fall_ie.u32, pin, 0);
    }

    if(edge & GPIO_PE_RISING)
    {
        set_gpio_bit(gpiohs->rise_ie.u32, pin, 1);
    } else
    {
        set_gpio_bit(gpiohs->rise_ie.u32, pin, 0);
    }

    if(edge & GPIO_PE_LOW)
    {
        set_gpio_bit(gpiohs->low_ie.u32, pin, 1);
    } else
    {
        set_gpio_bit(gpiohs->low_ie.u32, pin, 0);
    }

    if(edge & GPIO_PE_HIGH)
    {
        set_gpio_bit(gpiohs->high_ie.u32, pin, 1);
    } else
    {
        set_gpio_bit(gpiohs->high_ie.u32, pin, 0);
    }

    pin_instance[pin].edge = edge;
}

int gpiohs_pin_onchange_isr(void *userdata)
{
    gpiohs_pin_instance_t *ctx = (gpiohs_pin_instance_t *)userdata;
    size_t pin = ctx->pin;

    if(ctx->edge & GPIO_PE_FALLING)
    {
        set_gpio_bit(gpiohs->fall_ie.u32, pin, 0);
        set_gpio_bit(gpiohs->fall_ip.u32, pin, 1);
        set_gpio_bit(gpiohs->fall_ie.u32, pin, 1);
    }

    if(ctx->edge & GPIO_PE_RISING)
    {
        set_gpio_bit(gpiohs->rise_ie.u32, pin, 0);
        set_gpio_bit(gpiohs->rise_ip.u32, pin, 1);
        set_gpio_bit(gpiohs->rise_ie.u32, pin, 1);
    }

    if(ctx->edge & GPIO_PE_LOW)
    {
        set_gpio_bit(gpiohs->low_ie.u32, pin, 0);
        set_gpio_bit(gpiohs->low_ip.u32, pin, 1);
        set_gpio_bit(gpiohs->low_ie.u32, pin, 1);
    }

    if(ctx->edge & GPIO_PE_HIGH)
    {
        set_gpio_bit(gpiohs->high_ie.u32, pin, 0);
        set_gpio_bit(gpiohs->high_ip.u32, pin, 1);
        set_gpio_bit(gpiohs->high_ie.u32, pin, 1);
    }

    if(ctx->callback)
        ctx->callback();
    if(ctx->gpiohs_callback)
        ctx->gpiohs_callback(ctx->context);

    return 0;
}

void gpiohs_set_irq(uint8_t pin, uint32_t priority, void (*func)())
{

    pin_instance[pin].pin = pin;
    pin_instance[pin].callback = func;

    plic_set_priority(IRQN_GPIOHS0_INTERRUPT + pin, priority);
    plic_irq_register(IRQN_GPIOHS0_INTERRUPT + pin, gpiohs_pin_onchange_isr, &(pin_instance[pin]));
    plic_irq_enable(IRQN_GPIOHS0_INTERRUPT + pin);
}

void gpiohs_irq_register(uint8_t pin, uint32_t priority, plic_irq_callback_t callback, void *ctx)
{
    pin_instance[pin].pin = pin;
    pin_instance[pin].gpiohs_callback = callback;
    pin_instance[pin].context = ctx;

    plic_set_priority(IRQN_GPIOHS0_INTERRUPT + pin, priority);
    plic_irq_register(IRQN_GPIOHS0_INTERRUPT + pin, gpiohs_pin_onchange_isr, &(pin_instance[pin]));
    plic_irq_enable(IRQN_GPIOHS0_INTERRUPT + pin);
}

void gpiohs_irq_unregister(uint8_t pin)
{
    pin_instance[pin] = (gpiohs_pin_instance_t){
        .callback = NULL,
        .gpiohs_callback = NULL,
        .context = NULL,
    };
    set_gpio_bit(gpiohs->rise_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->fall_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->low_ie.u32, pin, 0);
    set_gpio_bit(gpiohs->high_ie.u32, pin, 0);
    plic_irq_unregister(IRQN_GPIOHS0_INTERRUPT + pin);
}

void gpiohs_irq_disable(size_t pin)
{
    plic_irq_disable(IRQN_GPIOHS0_INTERRUPT + pin);
}