/*
* easygpio.c
*
* Copyright (c) 2015, eadf (https://github.com/eadf)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Redis nor the names of its contributors may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

#include "easygpio.h"
#include "gpio.h"
#include "osapi.h"
#include "ets_sys.h"

#define EASYGPIO_USE_GPIO_INPUT_GET

static void ICACHE_FLASH_ATTR
gpio16_output_conf(void) {
  WRITE_PERI_REG(PAD_XPD_DCDC_CONF,
      (READ_PERI_REG(PAD_XPD_DCDC_CONF) & 0xffffffbcUL) | 0x1UL); // mux configuration for XPD_DCDC to output rtc_gpio0

  WRITE_PERI_REG(RTC_GPIO_CONF,
      (READ_PERI_REG(RTC_GPIO_CONF) & 0xfffffffeUL) | 0x0UL); //mux configuration for out enable

  WRITE_PERI_REG(RTC_GPIO_ENABLE,
      (READ_PERI_REG(RTC_GPIO_ENABLE) & 0xfffffffeUL) | 0x1UL); //out enable
}

static void ICACHE_FLASH_ATTR
gpio16_input_conf(void) {
  WRITE_PERI_REG(PAD_XPD_DCDC_CONF,
      (READ_PERI_REG(PAD_XPD_DCDC_CONF) & 0xffffffbcUL) | 0x1UL); // mux configuration for XPD_DCDC and rtc_gpio0 connection

  WRITE_PERI_REG(RTC_GPIO_CONF,
      (READ_PERI_REG(RTC_GPIO_CONF) & 0xfffffffeUL) | 0x0UL); //mux configuration for out enable

  WRITE_PERI_REG(RTC_GPIO_ENABLE,
      READ_PERI_REG(RTC_GPIO_ENABLE) & 0xfffffffeUL);  //out disable
}

/**
 * Returns the number of active pins in the gpioMask.
 */
uint8_t ICACHE_FLASH_ATTR
easygpio_countBits(uint32_t gpioMask) {

  uint8_t i=0;
  uint8_t numberOfPins=0;
  for (i=0; i<32; i++){
    numberOfPins += (gpioMask & BIT(i))?1:0;
  }
  return numberOfPins;
}

/**
 * Returns the gpio name and func for a specific pin.
 */
bool ICACHE_FLASH_ATTR
easygpio_getGPIONameFunc(uint8_t gpio_pin, uint32_t *gpio_name, uint8_t *gpio_func) {

  if (gpio_pin == 6 || gpio_pin == 7 || gpio_pin == 8 || gpio_pin == 11 || gpio_pin >= 17) {
    os_printf("easygpio_getGPIONameFunc Error: There is no GPIO%d, check your code\n", gpio_pin);
    return false;
  }
  if (gpio_pin == 16) {
    os_printf("easygpio_getGPIONameFunc Error: GPIO16 does not have gpio_name and gpio_func\n");
    return false;
  }
  switch ( gpio_pin ) {
    case 0:
      *gpio_func = FUNC_GPIO0;
      *gpio_name = PERIPHS_IO_MUX_GPIO0_U;
      return true;
    case 1:
      *gpio_func = FUNC_GPIO1;
      *gpio_name = PERIPHS_IO_MUX_U0TXD_U;
      return true;
    case 2:
      *gpio_func = FUNC_GPIO2;
      *gpio_name = PERIPHS_IO_MUX_GPIO2_U;
      return true;
    case 3:
      *gpio_func = FUNC_GPIO3;
      *gpio_name = PERIPHS_IO_MUX_U0RXD_U;
      return true;
    case 4:
      *gpio_func = FUNC_GPIO4;
      *gpio_name = PERIPHS_IO_MUX_GPIO4_U;
      return true;
    case 5:
      *gpio_func = FUNC_GPIO5;
      *gpio_name = PERIPHS_IO_MUX_GPIO5_U;
      return true;
    case 9:
      *gpio_func = FUNC_GPIO9;
      *gpio_name = PERIPHS_IO_MUX_SD_DATA2_U;
      return true;
    case 10:
      *gpio_func = FUNC_GPIO10;
      *gpio_name = PERIPHS_IO_MUX_SD_DATA3_U;
      return true;
    case 12:
      *gpio_func = FUNC_GPIO12;
      *gpio_name = PERIPHS_IO_MUX_MTDI_U;
      return true;
    case 13:
      *gpio_func = FUNC_GPIO13;
      *gpio_name = PERIPHS_IO_MUX_MTCK_U;
      return true;
    case 14:
      *gpio_func = FUNC_GPIO14;
      *gpio_name = PERIPHS_IO_MUX_MTMS_U;
      return true;
    case 15:
      *gpio_func = FUNC_GPIO15;
      *gpio_name = PERIPHS_IO_MUX_MTDO_U;
      return true;
    default:
      return false;
  }
  return true;
}

/**
 * Sets the pull up registers for a pin.
 */
static void ICACHE_FLASH_ATTR
easygpio_setupPullsByName(uint32_t gpio_name, EasyGPIO_PullStatus pullStatus) {

  if (EASYGPIO_PULLUP == pullStatus) {
    PIN_PULLUP_EN(gpio_name);
  } else {
    PIN_PULLUP_DIS(gpio_name);
  }
}

/**
 * Sets the pull registers for a pin.
 */
bool ICACHE_FLASH_ATTR
easygpio_pullMode(uint8_t gpio_pin, EasyGPIO_PullStatus pullStatus) {
  uint32_t gpio_name;
  uint8_t gpio_func;

  if (!easygpio_getGPIONameFunc(gpio_pin, &gpio_name, &gpio_func) ) {
    return false;
  }

  easygpio_setupPullsByName(gpio_name, pullStatus);
  return true;
}

/**
 * Sets the 'gpio_pin' pin as a GPIO and sets the pull register for that pin.
 * 'pullStatus' has no effect on output pins or GPIO16
 */
bool ICACHE_FLASH_ATTR
easygpio_pinMode(uint8_t gpio_pin, EasyGPIO_PullStatus pullStatus, EasyGPIO_PinMode pinMode) {
  uint32_t gpio_name;
  uint8_t gpio_func;

  if (16==gpio_pin) {
    // ignoring pull status on GPIO16 for now
    if (EASYGPIO_OUTPUT == pinMode) {
      gpio16_output_conf();
    } else {
      gpio16_input_conf();
    }
    return true;
  } else if (!easygpio_getGPIONameFunc(gpio_pin, &gpio_name, &gpio_func) ) {
    return false;
  }

  PIN_FUNC_SELECT(gpio_name, gpio_func);
  easygpio_setupPullsByName(gpio_name, pullStatus);

  if (EASYGPIO_OUTPUT != pinMode) {
    GPIO_DIS_OUTPUT(GPIO_ID_PIN(gpio_pin));
  } else {
    // must enable the pin or else the WRITE_PERI_REG won't work
    gpio_output_set(0, 0, BIT(GPIO_ID_PIN(gpio_pin)),0);
  }
  return true;
}

/**
 * Sets the 'gpio_pin' pin as a GPIO and sets the interrupt to trigger on that pin.
 * The 'interruptArg' is the function argument that will be sent to your interruptHandler
 */
bool ICACHE_FLASH_ATTR
easygpio_attachInterrupt(uint8_t gpio_pin, EasyGPIO_PullStatus pullStatus, void (*interruptHandler)(void *arg), void *interruptArg) {
  uint32_t gpio_name;
  uint8_t gpio_func;

  if (gpio_pin == 16) {
    os_printf("easygpio_setupInterrupt Error: GPIO16 does not have interrupts\n");
    return false;
  }
  if (!easygpio_getGPIONameFunc(gpio_pin, &gpio_name, &gpio_func) ) {
    return false;
  }

  ETS_GPIO_INTR_ATTACH(interruptHandler, interruptArg);
  ETS_GPIO_INTR_DISABLE();

  PIN_FUNC_SELECT(gpio_name, gpio_func);

  easygpio_setupPullsByName(gpio_name, pullStatus);

  // disable output
  GPIO_DIS_OUTPUT(gpio_pin);

  gpio_register_set(GPIO_PIN_ADDR(gpio_pin), GPIO_PIN_INT_TYPE_SET(GPIO_PIN_INTR_DISABLE)
                    | GPIO_PIN_PAD_DRIVER_SET(GPIO_PAD_DRIVER_DISABLE)
                    | GPIO_PIN_SOURCE_SET(GPIO_AS_PIN_SOURCE));

  //clear gpio14 status
  GPIO_REG_WRITE(GPIO_STATUS_W1TC_ADDRESS, BIT(gpio_pin));
  ETS_GPIO_INTR_ENABLE();

  return true;
}

/**
 * Detach the interrupt handler from the 'gpio_pin' pin.
 */
bool ICACHE_FLASH_ATTR
easygpio_detachInterrupt(uint8_t gpio_pin) {

  if (gpio_pin == 16) {
    os_printf("easygpio_setupInterrupt Error: GPIO16 does not have interrupts\n");
    return false;
  }

  // Don't know how to detach interrupt, yet.
  // Quick and dirty fix - just disable the interrupt
  gpio_pin_intr_state_set(GPIO_ID_PIN(gpio_pin), GPIO_PIN_INTR_DISABLE);
  return true;
}

/**
 * Uniform way of setting GPIO output value. Handles GPIO 0-16.
 *
 * You can not rely on that this function will switch the gpio to an output like GPIO_OUTPUT_SET does.
 * Use easygpio_outputEnable() to change an input gpio to output mode.
 */
void
easygpio_outputSet(uint8_t gpio_pin, uint8_t value) {
  if (16==gpio_pin) {
    WRITE_PERI_REG(RTC_GPIO_OUT,
                   (READ_PERI_REG(RTC_GPIO_OUT) & 0xfffffffeUL) | (0x1UL & value));
  } else {
#ifdef EASYGPIO_USE_GPIO_OUTPUT_SET
    GPIO_OUTPUT_SET(GPIO_ID_PIN(gpio_pin), value);
#else
    if (value&1){
      WRITE_PERI_REG( PERIPHS_GPIO_BASEADDR, READ_PERI_REG(PERIPHS_GPIO_BASEADDR) | BIT(gpio_pin));
    } else {
      WRITE_PERI_REG( PERIPHS_GPIO_BASEADDR, READ_PERI_REG(PERIPHS_GPIO_BASEADDR) & ~BIT(gpio_pin));
    }
#endif
  }
}

/**
 * Uniform way of getting GPIO input value. Handles GPIO 0-16.
 * The pin must be initiated with easygpio_pinMode() so that the pin mux is setup as a gpio in the first place.
 * If you know that you won't be using GPIO16 then you'd better off by just using GPIO_INPUT_GET().
 */
uint8_t
easygpio_inputGet(uint8_t gpio_pin) {
  if (16==gpio_pin) {
    return (READ_PERI_REG(RTC_GPIO_IN_DATA) & 1UL);
  } else {
#ifdef EASYGPIO_USE_GPIO_INPUT_GET
    return GPIO_INPUT_GET(GPIO_ID_PIN(gpio_pin));
#else
  // this does *not* work, maybe GPIO_IN_ADDRESS is the wrong address
  return ((GPIO_REG_READ(GPIO_IN_ADDRESS) > gpio_pin)  & 1UL);
#endif
  }
}

/**
 * Uniform way of turning an output GPIO pin into input mode. Handles GPIO 0-16.
 * The pin must be initiated with easygpio_pinMode() so that the pin mux is setup as a gpio in the first place.
 * This function does the same thing as GPIO_DIS_OUTPUT, but works on GPIO16 too.
 */
void easygpio_outputDisable(uint8_t gpio_pin) {
  if (16==gpio_pin) {
    WRITE_PERI_REG(RTC_GPIO_ENABLE,
        READ_PERI_REG(RTC_GPIO_ENABLE) & 0xfffffffeUL);  //out disable
  } else {
    GPIO_DIS_OUTPUT(GPIO_ID_PIN(gpio_pin));
  }
}

/**
 * Uniform way of turning an input GPIO pin into output mode. Handles GPIO 0-16.
 * The pin must be initiated with easygpio_pinMode() so that the pin mux is setup as a gpio in the first place.
 *
 * This function:
 *  - should only be used to convert a input pin into an output pin.
 *  - is a little bit slower than easygpio_outputSet() so you should use that
 *    function to just change output value.
 *  - does the same thing as GPIO_OUTPUT_SET, but works on GPIO16 too.
 */
void easygpio_outputEnable(uint8_t gpio_pin, uint8_t value) {
  if (16==gpio_pin) {
    // write the value before flipping to output
    // - so we don't flash previous value for a few ns.
    WRITE_PERI_REG(RTC_GPIO_OUT,
                           (READ_PERI_REG(RTC_GPIO_OUT) & 0xfffffffeUL) | (0x1UL & value));

    WRITE_PERI_REG(RTC_GPIO_ENABLE,
          (READ_PERI_REG(RTC_GPIO_ENABLE) & 0xfffffffeUL) | 0x1UL); //out enable

  } else {
    GPIO_OUTPUT_SET(GPIO_ID_PIN(gpio_pin), value);
  }
}