/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 <string.h>
#include <stdlib.h>
#include <assert.h>

#include "os/mynewt.h"

#include <hal/hal_i2c.h>
#include <hal/hal_gpio.h>

#include <mcu/stm32_hal.h>

#define HAL_I2C_MAX_DEVS    3

#define I2C_ADDRESS         0xae

extern HAL_StatusTypeDef HAL_I2C_Master_Transmit_Custom(I2C_HandleTypeDef *hi2c,
        uint16_t DevAddress, uint8_t *pData, uint16_t Size, uint32_t Timeout,
        uint8_t LastOp);
extern HAL_StatusTypeDef HAL_I2C_Master_Receive_Custom(I2C_HandleTypeDef *hi2c,
        uint16_t DevAddress, uint8_t *pData, uint16_t Size, uint32_t Timeout,
        uint8_t LastOp);

struct stm32_hal_i2c {
    I2C_HandleTypeDef hid_handle;
};

#if MYNEWT_VAL(I2C_0)
static struct stm32_hal_i2c i2c0;
#endif
#if MYNEWT_VAL(I2C_1)
static struct stm32_hal_i2c i2c1;
#endif
#if MYNEWT_VAL(I2C_2)
static struct stm32_hal_i2c i2c2;
#endif

static struct stm32_hal_i2c *hal_i2c_devs[HAL_I2C_MAX_DEVS] = {
#if MYNEWT_VAL(I2C_0)
    &i2c0,
#else
    NULL,
#endif
#if MYNEWT_VAL(I2C_1)
    &i2c1,
#else
    NULL,
#endif
#if MYNEWT_VAL(I2C_2)
    &i2c2,
#else
    NULL,
#endif
};

#if MYNEWT_VAL(MCU_STM32F1)
static void
i2c_reset(I2C_HandleTypeDef *hi2c)
{
    __HAL_I2C_DISABLE(hi2c);
    hi2c->Instance->CR1 |= I2C_CR1_SWRST;
    hi2c->Instance->CR1 &= ~I2C_CR1_SWRST;
    __HAL_I2C_ENABLE(hi2c);
}
#endif

int
hal_i2c_init(uint8_t i2c_num, void *usercfg)
{
    struct stm32_hal_i2c_cfg *cfg = (struct stm32_hal_i2c_cfg *)usercfg;
    struct stm32_hal_i2c *dev;
    I2C_InitTypeDef *init;
#if MYNEWT_VAL(MCU_STM32F1)
    GPIO_InitTypeDef gpio;
#endif
    int rc;

    if (i2c_num >= HAL_I2C_MAX_DEVS || !(dev = hal_i2c_devs[i2c_num])) {
        return -1;
    }

    init = &dev->hid_handle.Init;
    dev->hid_handle.Instance = cfg->hic_i2c;
#if !MYNEWT_VAL(STM32_HAL_I2C_HAS_CLOCKSPEED)
    init->Timing = cfg->hic_timingr;
#else
    init->ClockSpeed = cfg->hic_speed;
#endif
    if (cfg->hic_10bit) {
        init->AddressingMode = I2C_ADDRESSINGMODE_10BIT;
    } else {
        init->AddressingMode = I2C_ADDRESSINGMODE_7BIT;
    }
    init->OwnAddress1 = I2C_ADDRESS;
    init->OwnAddress2 = 0xFE;

    /*
     * Configure GPIO pins for I2C.
     * Enable clock routing for I2C.
     */
#if !MYNEWT_VAL(MCU_STM32F1)
    rc = hal_gpio_init_af(cfg->hic_pin_sda, cfg->hic_pin_af, HAL_GPIO_PULL_UP,
                          1);
    if (rc) {
        goto err;
    }
    rc = hal_gpio_init_af(cfg->hic_pin_scl, cfg->hic_pin_af, HAL_GPIO_PULL_UP,
                          1);
    if (rc) {
        goto err;
    }

    *cfg->hic_rcc_reg |= cfg->hic_rcc_dev;
#else
    /* For STM32F1x initialize I2C clock before GPIOs */
    *cfg->hic_rcc_reg |= cfg->hic_rcc_dev;

    if (cfg->hic_pin_remap_fn != NULL) {
        cfg->hic_pin_remap_fn();
    }

    /*
     * The block below applies a workaround described in 2.13.7
     * of the STM32F103 errata (also described on F105/107 errata).
     */
    gpio.Mode = GPIO_MODE_OUTPUT_OD;
    gpio.Speed = GPIO_SPEED_FREQ_LOW;
    gpio.Pull = GPIO_NOPULL;

    hal_gpio_init_stm(cfg->hic_pin_sda, &gpio);
    hal_gpio_write(cfg->hic_pin_sda, 1);
    hal_gpio_init_stm(cfg->hic_pin_scl, &gpio);
    hal_gpio_write(cfg->hic_pin_scl, 1);

    assert(hal_gpio_read(cfg->hic_pin_sda) == 1);
    assert(hal_gpio_read(cfg->hic_pin_scl) == 1);

    hal_gpio_write(cfg->hic_pin_sda, 0);
    assert(hal_gpio_read(cfg->hic_pin_sda) == 0);

    hal_gpio_write(cfg->hic_pin_scl, 0);
    assert(hal_gpio_read(cfg->hic_pin_scl) == 0);

    hal_gpio_write(cfg->hic_pin_scl, 1);
    assert(hal_gpio_read(cfg->hic_pin_scl) == 1);

    hal_gpio_write(cfg->hic_pin_sda, 1);
    assert(hal_gpio_read(cfg->hic_pin_sda) == 1);

    /*
     * Normal I2C PIN initialization
     */
    gpio.Mode = GPIO_MODE_AF_OD;
    gpio.Speed = GPIO_SPEED_FREQ_HIGH;
    /* NOTE: Pull is not used in AF mode */
    gpio.Pull = GPIO_NOPULL;

    hal_gpio_init_stm(cfg->hic_pin_scl, &gpio);
    hal_gpio_init_stm(cfg->hic_pin_sda, &gpio);

    /*
     * Reset I2C
     */
    dev->hid_handle.Instance->CR1 = I2C_CR1_SWRST;
    dev->hid_handle.Instance->CR1 = 0;
#endif

    rc = HAL_I2C_Init(&dev->hid_handle);
    if (rc) {
        goto err;
    }

    return 0;
err:
    *cfg->hic_rcc_reg &= ~cfg->hic_rcc_dev;
    return rc;
}

int
hal_i2c_master_write(uint8_t i2c_num, struct hal_i2c_master_data *data,
  uint32_t timo, uint8_t last_op)
{
    struct stm32_hal_i2c *dev;

    if (i2c_num >= HAL_I2C_MAX_DEVS || !(dev = hal_i2c_devs[i2c_num])) {
        return -1;
    }

    return HAL_I2C_Master_Transmit_Custom(&dev->hid_handle, data->address << 1,
            data->buffer, data->len, timo, last_op);
}

int
hal_i2c_master_read(uint8_t i2c_num, struct hal_i2c_master_data *pdata,
  uint32_t timo, uint8_t last_op)
{
    struct stm32_hal_i2c *dev;

    if (i2c_num >= HAL_I2C_MAX_DEVS || !(dev = hal_i2c_devs[i2c_num])) {
        return -1;
    }

    return HAL_I2C_Master_Receive_Custom(&dev->hid_handle, pdata->address << 1,
      pdata->buffer, pdata->len, timo, last_op);
}

int
hal_i2c_master_probe(uint8_t i2c_num, uint8_t address, uint32_t timo)
{
    struct stm32_hal_i2c *dev;
    int rc;

    if (i2c_num >= HAL_I2C_MAX_DEVS || !(dev = hal_i2c_devs[i2c_num])) {
        return -1;
    }

    rc = HAL_I2C_IsDeviceReady(&dev->hid_handle, address << 1, 1, timo);

#if MYNEWT_VAL(MCU_STM32F1)
    if (rc == HAL_BUSY) {
        i2c_reset(&dev->hid_handle);
    }
#endif

    return rc;
}