File content as of revision 70:c1fbde68b492:

/* mbed Microcontroller Library
 *******************************************************************************
 * Copyright (c) 2014, STMicroelectronics
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of STMicroelectronics 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 HOLDER 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 "pinmap.h"
#include "error.h"

// Alternate-function mapping
static const uint32_t AF_mapping[] = {
  0,                      // 0 = No AF
  GPIO_Remap_SPI1,        // 1
  GPIO_Remap_I2C1,        // 2
  GPIO_Remap_USART1,      // 3
  GPIO_Remap_USART2,      // 4
  GPIO_FullRemap_TIM2,    // 5
  GPIO_FullRemap_TIM3,    // 6
  GPIO_PartialRemap_TIM3, // 7
  GPIO_Remap_I2C1         // 8
};

/**
 * Set the pin function (input, output, alternate function or analog) + output speed + AF
 */
void pin_function(PinName pin, int data) {
    if (pin == NC) return;

    // Get the pin mode and alternate-function number
    uint32_t mode  = STM_PIN_MODE(data);
    uint32_t afnum = STM_PIN_AFNUM(data);

    // Get GPIO structure base address
    uint32_t pin_number = (uint32_t)pin;
    uint32_t pin_index  = (pin_number & 0xF);
    uint32_t port_index = (pin_number >> 4);
    GPIO_TypeDef *gpio  = ((GPIO_TypeDef *)(GPIOA_BASE + (port_index << 10)));

    // Enable GPIO and AFIO clocks
    RCC_APB2PeriphClockCmd((uint32_t)(RCC_APB2Periph_GPIOA << port_index), ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
  
    // Configure GPIO
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Pin   = (uint16_t)(1 << pin_index);
    GPIO_InitStructure.GPIO_Mode  = (GPIOMode_TypeDef)mode;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(gpio, &GPIO_InitStructure);

    // Configure Alternate Function
    if (afnum > 0) {
        GPIO_PinRemapConfig(AF_mapping[afnum], ENABLE);
    }
    
    // Disconnect JTAG-DP + SW-DP signals.
    // Warning: Need to reconnect under reset
    if ((pin == PA_13) || (pin == PA_14)) {
        GPIO_PinRemapConfig(GPIO_Remap_SWJ_Disable, ENABLE);
    }
    if ((pin == PA_15) || (pin == PB_3) || (pin == PB_4)) {
        GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);
    }    
}

/**
 * Set the pin mode (open-drain/push-pull + pull-up/pull-down)
 */
void pin_mode(PinName pin, PinMode mode) {
    if (pin == NC) return;

    GPIO_InitTypeDef GPIO_InitStructure;
  
    // Get GPIO structure base address
    uint32_t pin_number = (uint32_t)pin;
    uint32_t pin_index  = (pin_number & 0xF);
    uint32_t port_index = (pin_number >> 4);
    GPIO_TypeDef *gpio  = ((GPIO_TypeDef *)(GPIOA_BASE + (port_index << 10)));

    // Enable GPIO clock
    RCC_APB2PeriphClockCmd((uint32_t)(RCC_APB2Periph_GPIOA << port_index), ENABLE);
  
    // Configure open-drain and pull-up/down
    switch (mode) {
      case PullNone:       
        return;
      case PullUp:
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
      break;
      case PullDown:
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD;
      break;
      case OpenDrain:
        if (pin_index < 8) {
            if ((gpio->CRL & (0x03 << (pin_index * 4))) > 0) { // MODE bits = Output mode
                gpio->CRL |= (0x04 << (pin_index * 4)); // Set open-drain
            }
        }
        else {
            if ((gpio->CRH & (0x03 << ((pin_index % 8) * 4))) > 0) { // MODE bits = Output mode          
                gpio->CRH |= (0x04 << ((pin_index % 8) * 4)); // Set open-drain
            }
        }
        return;
      default:
      break;
    }
    
    // Configure GPIO
    GPIO_InitStructure.GPIO_Pin   = (uint16_t)(1 << pin_index);
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(gpio, &GPIO_InitStructure);    
}