/*
 * Copyright (C) 2022 Gunar Schorcht
 *
 * 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_esp32
 * @ingroup     drivers_periph_gpio
 * @{
 *
 * @file
 * @brief       Low-level GPIO driver implementation for ESP32
 *
 * @author      Gunar Schorcht <gunar@schorcht.net>
 * @}
 */

#include <assert.h>
#include <stdbool.h>

#include "log.h"
#include "periph/gpio.h"    /* RIOT gpio.h */

#include "hal/gpio_hal.h"
#include "hal/gpio_types.h"
#include "hal/rtc_io_types.h"
#include "esp/common_macros.h"
#include "esp_intr_alloc.h"
#include "rom/ets_sys.h"
#include "soc/gpio_reg.h"
#include "soc/gpio_sig_map.h"
#include "soc/gpio_struct.h"
#include "soc/io_mux_reg.h"
#include "soc/rtc_cntl_reg.h"
#include "soc/rtc_io_periph.h"

#if __xtensa__
#include "xtensa/xtensa_api.h"
#endif

#include "esp_idf_api/gpio.h"

#include "adc_arch.h"
#include "bitfield.h"
#include "esp_common.h"
#include "esp_sleep.h"
#include "gpio_arch.h"
#include "irq_arch.h"
#include "syscalls.h"

#define ENABLE_DEBUG 0
#include "debug.h"

#define ESP_PM_WUP_PINS_ANY_HIGH    ESP_EXT1_WAKEUP_ANY_HIGH
#define ESP_PM_WUP_PINS_ALL_LOW     ESP_EXT1_WAKEUP_ALL_LOW

#ifndef ESP_PM_WUP_LEVEL
#define ESP_PM_WUP_LEVEL            ESP_PM_WUP_PINS_ANY_HIGH
#endif

#define GPIO_PRO_CPU_INTR_ENA       (BIT(2))

/* architecture specific tables */
extern gpio_pin_usage_t _gpio_pin_usage [GPIO_PIN_NUMOF];
#if !IS_USED(MODULE_ESP_IDF_GPIO_HAL)
extern const uint32_t _gpio_to_iomux_reg[GPIO_PIN_NUMOF];
#endif

/* String representation of usage types */
const char* _gpio_pin_usage_str[] =
{
    "GPIO", "ADC", "CAN", "DAC", "EMAC", "I2C", "PWM", "SPI", "SPI Flash", "UART", "N/A"
};

#ifdef ESP_PM_WUP_PINS
/* for saving the pullup/pulldown settings of wakeup pins in deep sleep mode */
static bool _gpio_pin_pu[GPIO_PIN_NUMOF] = { };
static bool _gpio_pin_pd[GPIO_PIN_NUMOF] = { };
#endif

#if defined(CPU_FAM_ESP32)

#define GPIO_IN_GET(b)  (b < 32) ? GPIO.in & BIT(b) : GPIO.in1.val & BIT(b-32)
#define GPIO_OUT_SET(b) if (b < 32) { GPIO.out_w1ts = BIT(b); } else { GPIO.out1_w1ts.val = BIT(b-32); }
#define GPIO_OUT_CLR(b) if (b < 32) { GPIO.out_w1tc = BIT(b); } else { GPIO.out1_w1tc.val = BIT(b-32); }
#define GPIO_OUT_XOR(b) if (b < 32) { GPIO.out ^=  BIT(b); } else { GPIO.out1.val ^=  BIT(b-32); }
#define GPIO_OUT_GET(b) (b < 32) ? (GPIO.out >> b) & 1 : (GPIO.out1.val >> (b-32)) & 1

#else
#error "Platform implementation is missing"
#endif

#ifndef NDEBUG
int _gpio_init_mode_check(gpio_t pin, gpio_mode_t mode)
{
    assert(pin < GPIO_PIN_NUMOF);

    /* check if the pin can be used as GPIO or if it is used for something else */
    if (_gpio_pin_usage[pin] != _GPIO) {
        LOG_TAG_ERROR("gpio", "GPIO%d is already used as %s signal\n", pin,
                      _gpio_pin_usage_str[_gpio_pin_usage[pin]]);
        return -1;
    }
    return 0;
}
#endif

int gpio_init(gpio_t pin, gpio_mode_t mode)
{
    DEBUG("%s: gpio=%d mode=%d\n", __func__, pin, mode);
    assert(_gpio_init_mode_check(pin, mode) == 0);
    assert(pin < GPIO_PIN_NUMOF);

    gpio_config_t cfg = { };

#if SOC_RTCIO_INPUT_OUTPUT_SUPPORTED
    /* if we come from deep sleep, the GPIO is configured as RTC IO */
    esp_idf_rtc_gpio_deinit(pin);
#endif

    cfg.pin_bit_mask = (1ULL << pin);

    switch (mode) {
    case GPIO_IN:
    case GPIO_IN_PD:
    case GPIO_IN_PU:
        cfg.mode = GPIO_MODE_DEF_INPUT;
        break;
    case GPIO_IN_OD:
    case GPIO_IN_OD_PU:
        cfg.mode = (GPIO_MODE_DEF_INPUT) | (GPIO_MODE_DEF_OUTPUT) | (GPIO_MODE_DEF_OD);
        break;
    case GPIO_IN_OUT:
        cfg.mode = (GPIO_MODE_DEF_INPUT) | (GPIO_MODE_DEF_OUTPUT);
        break;
    case GPIO_OUT:
        cfg.mode = GPIO_MODE_DEF_OUTPUT;
        break;
    case GPIO_OD:
    case GPIO_OD_PU:
        cfg.mode = (GPIO_MODE_DEF_OUTPUT) | (GPIO_MODE_DEF_OD);
        break;
    }

    /* digital GPIO configuration */
    cfg.pull_up_en = ((mode == GPIO_IN_PU) ||
                      (mode == GPIO_OD_PU) ||
                      (mode == GPIO_IN_OD_PU)) ? GPIO_PULLUP_ENABLE
                                               : GPIO_PULLUP_DISABLE;
    cfg.pull_down_en = (mode == GPIO_IN_PD) ? GPIO_PULLUP_ENABLE
                                            : GPIO_PULLUP_DISABLE;
    cfg.intr_type = GPIO_INTR_DISABLE;

#ifdef ESP_PM_WUP_PINS
/* for saving the pullup/pulldown settings of wakeup pins in deep sleep mode */
    _gpio_pin_pu[pin] = cfg.pull_up_en;
    _gpio_pin_pd[pin] = cfg.pull_down_en;
#endif

    return (esp_idf_gpio_config(&cfg) == ESP_OK) ? 0 : -1;
}

#if MODULE_PERIPH_GPIO_IRQ

/* interrupt enabled state is required for sleep modes */
static bool gpio_int_enabled_table[GPIO_PIN_NUMOF] = { };

static bool _isr_installed = false;

int gpio_init_int(gpio_t pin, gpio_mode_t mode, gpio_flank_t flank,
                  gpio_cb_t cb, void *arg)
{
    DEBUG("%s: gpio=%d mode=%d flank=%d\n", __func__, pin, mode, flank);
    assert(_gpio_init_mode_check(pin, mode) == 0);

    if (gpio_init(pin, mode) != 0) {
        return -1;
    }

    gpio_int_type_t type = GPIO_INTR_DISABLE;

    switch (flank) {
    case GPIO_NONE:
        type = GPIO_INTR_DISABLE;
        break;
    case GPIO_RISING:
        type = GPIO_INTR_POSEDGE;
        break;
    case GPIO_FALLING:
        type = GPIO_INTR_NEGEDGE;
        break;
    case GPIO_BOTH:
        type = GPIO_INTR_ANYEDGE;
        break;
    case GPIO_LOW:
        type = GPIO_INTR_LOW_LEVEL;
        break;
    case GPIO_HIGH:
        type = GPIO_INTR_HIGH_LEVEL;
        break;
    }

    if (esp_idf_gpio_set_intr_type(pin, type) != ESP_OK) {
        return -1;
    }

    if (!_isr_installed &&
        esp_idf_gpio_install_isr_service(ESP_INTR_FLAG_LEVEL1) != ESP_OK) {
        return -1;
    }
    _isr_installed = true;

    if (esp_idf_gpio_isr_handler_add(pin, cb, arg) != ESP_OK) {
        return -1;
    }

    gpio_irq_enable(pin);

    return (gpio_int_enabled_table[pin]) ? 0 : -1;
}

void gpio_irq_enable(gpio_t pin)
{
    DEBUG("%s: gpio=%d\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);

    if (esp_idf_gpio_intr_enable(pin) == ESP_OK) {
        gpio_int_enabled_table[pin] = true;
    }
}

void gpio_irq_disable(gpio_t pin)
{
    DEBUG("%s: gpio=%d\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);

    if (esp_idf_gpio_intr_disable(pin) == ESP_OK) {
        gpio_int_enabled_table[pin] = false;
    }
}

#endif /* MODULE_PERIPH_GPIO_IRQ */

#if IS_USED(MODULE_ESP_IDF_GPIO_HAL)

static gpio_hal_context_t _gpio_hal_ctx = {
    .dev = GPIO_HAL_GET_HW(GPIO_PORT_0)
};

/*
 * Since `gpio_hal_get_level` returns the current pin level and not the value
 * last written to the output, we have to handle the state of each pin in a
 * separate static variable.
 */
static BITFIELD(_output, GPIO_PIN_NUMOF);

int gpio_read(gpio_t pin)
{
    assert(pin < GPIO_PIN_NUMOF);

    /* if the pin is not an input, it alsways returns 0 */
    /* TODO: not really clear whether it should return the last written value
     *       in this case. */
    int value = gpio_hal_get_level(&_gpio_hal_ctx, pin);

    DEBUG("%s gpio=%u val=%d\n", __func__, pin, value);
    return value;
}

void gpio_write(gpio_t pin, int value)
{
    DEBUG("%s gpio=%u val=%d\n", __func__, pin, value);
    assert(pin < GPIO_PIN_NUMOF);

    if (value) {
        bf_set(_output, pin);
    }
    else {
        bf_unset(_output, pin);
    }
    gpio_hal_set_level(&_gpio_hal_ctx, pin, value);
}

void gpio_set(gpio_t pin)
{
    DEBUG("%s gpio=%u\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);

    bf_set(_output, pin);
    gpio_hal_set_level(&_gpio_hal_ctx, pin, 1);
}

void gpio_clear(gpio_t pin)
{
    DEBUG("%s gpio=%u\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);

    bf_unset(_output, pin);
    gpio_hal_set_level(&_gpio_hal_ctx, pin, 0);
}

void gpio_toggle(gpio_t pin)
{
    DEBUG("%s gpio=%u\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);

    bf_toggle(_output, pin);
    gpio_hal_set_level(&_gpio_hal_ctx, pin, bf_isset(_output, pin) ? 1 : 0);
}

#else /* IS_USED(MODULE_ESP_IDF_GPIO_HAL) */

int gpio_read(gpio_t pin)
{
    assert(pin < GPIO_PIN_NUMOF);

    int value;

    if (REG_GET_BIT(_gpio_to_iomux_reg[pin], FUN_IE)) {
        /* in case the pin is any kind of input, read from input register */
        value = (GPIO_IN_GET(pin)) ? 1 : 0;
    }
    else {
        /* otherwise read the last value written to the output register */
        value = GPIO_OUT_GET(pin);
    }
    DEBUG("%s gpio=%u val=%d\n", __func__, pin, value);
    return value;
}

void gpio_write(gpio_t pin, int value)
{
    DEBUG("%s gpio=%u val=%d\n", __func__, pin, value);
    assert(pin < GPIO_PIN_NUMOF);
    if (value) {
        GPIO_OUT_SET(pin);
    }
    else {
        GPIO_OUT_CLR(pin);
    }
}

void gpio_set(gpio_t pin)
{
    DEBUG("%s gpio=%u\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);
    GPIO_OUT_SET(pin);
}

void gpio_clear(gpio_t pin)
{
    DEBUG("%s gpio=%u\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);
    GPIO_OUT_CLR(pin);

}

void gpio_toggle(gpio_t pin)
{
    DEBUG("%s gpio=%u\n", __func__, pin);
    assert(pin < GPIO_PIN_NUMOF);
    GPIO_OUT_XOR(pin);
}

#endif /* IS_USED(MODULE_ESP_IDF_GPIO_HAL) */

int gpio_set_pin_usage(gpio_t pin, gpio_pin_usage_t usage)
{
    assert(pin < GPIO_PIN_NUMOF);
    _gpio_pin_usage[pin] = usage;
    return 0;
}

gpio_pin_usage_t gpio_get_pin_usage (gpio_t pin)
{
    return (pin < GPIO_PIN_NUMOF) ? _gpio_pin_usage[pin] : _NOT_EXIST;
}

const char* gpio_get_pin_usage_str(gpio_t pin)
{
    return _gpio_pin_usage_str[_gpio_pin_usage[((pin < GPIO_PIN_NUMOF) ? pin : _NOT_EXIST)]];
}

#if MODULE_PERIPH_GPIO_IRQ
static uint32_t gpio_int_saved_type[GPIO_PIN_NUMOF];
#endif

void gpio_pm_sleep_enter(unsigned mode)
{
    if (mode == ESP_PM_DEEP_SLEEP) {
#ifdef ESP_PM_GPIO_HOLD
        /*
         * Activate the power domain for RTC peripherals when
         * ESP_PM_GPIO_HOLD is defined for deep sleep mode.
         */
        esp_idf_gpio_deep_sleep_hold();
        esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_ON);
#endif

#ifdef ESP_PM_WUP_PINS
        static const gpio_t wup_pins[] = { ESP_PM_WUP_PINS };
        /*
         * Prepare the wake-up pins if a single pin or a comma-separated list of
         * pins is defined for wake-up.
         */
        uint64_t wup_pin_mask = 0;
        for (unsigned i = 0; i < ARRAY_SIZE(wup_pins); i++) {
            wup_pin_mask |= 1ULL << wup_pins[i];

#if SOC_RTCIO_INPUT_OUTPUT_SUPPORTED
            /* If internal pullups/pulldowns are used, they have to be
               activated also in deep sleep mode in RTC power domain */
            bool pu_pd_used = false;

            assert(rtc_io_num_map[wup_pins[i]] >= 0);
            if (_gpio_pin_pu[wup_pins[i]]) {
                pu_pd_used = true;
                esp_idf_rtc_gpio_pullup_en(wup_pins[i]);
            }
            else {
                esp_idf_rtc_gpio_pullup_dis(wup_pins[i]);
            }
            if (_gpio_pin_pd[wup_pins[i]]) {
                pu_pd_used = true;
                esp_idf_rtc_gpio_pulldown_en(wup_pins[i]);
            }
            else {
                esp_idf_rtc_gpio_pulldown_dis(wup_pins[i]);
            }
            if (pu_pd_used) {
                /* If internal pullups/pulldowns are used, the RTC power domain
                 * must remain active in deep sleep mode */
                esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_ON);
            }
#endif /* SOC_RTCIO_INPUT_OUTPUT_SUPPORTED */
        }
        esp_sleep_enable_ext1_wakeup(wup_pin_mask, ESP_PM_WUP_LEVEL);
#endif /* ESP_PM_WUP_PINS */
    }
    else {
#if MODULE_PERIPH_GPIO_IRQ
        for (unsigned i = 0; i < GPIO_PIN_NUMOF; i++) {
            if (gpio_int_enabled_table[i] && GPIO.pin[i].int_type) {
                gpio_int_saved_type[i] = GPIO.pin[i].int_type;
                switch (gpio_int_saved_type[i]) {
                    case GPIO_LOW:
                    case GPIO_FALLING:
                        esp_idf_gpio_wakeup_enable(i, GPIO_INTR_LOW_LEVEL);
                        DEBUG("%s gpio=%u GPIO_LOW\n", __func__, i);
                        break;
                    case GPIO_HIGH:
                    case GPIO_RISING:
                        esp_idf_gpio_wakeup_enable(i, GPIO_INTR_HIGH_LEVEL);
                        DEBUG("%s gpio=%u GPIO_HIGH\n", __func__, i);
                        break;
                    case GPIO_BOTH:
                        DEBUG("%s gpio=%u GPIO_BOTH not supported\n",
                               __func__, i);
                        break;
                    default:
                        break;
                }
            }
        }
        esp_sleep_enable_gpio_wakeup();
#endif
    }
}

void gpio_pm_sleep_exit(uint32_t cause)
{
    (void)cause;
#if MODULE_PERIPH_GPIO_IRQ
    DEBUG("%s\n", __func__);
    for (unsigned i = 0; i < GPIO_PIN_NUMOF; i++) {
        if (gpio_int_enabled_table[i]) {
            GPIO.pin[i].int_type = gpio_int_saved_type[i];
        }
    }
#endif
}