text: /************************************************************************************
   *
   * Copyright 2016 Samsung Electronics All Rights Reserved.
   *
   * 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.
   *
   ************************************************************************************/
  /************************************************************************************
   * arch/arm/src/stm32l4/stm32l4_qencoder.h
   *
   *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
   *   Author: Gregory Nutt <gnutt@nuttx.org>
   *
   * 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 NuttX 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.
   *
   ************************************************************************************/
  
  #ifndef __ARCH_ARM_SRC_STM32L4_STM32L4_QENCODER_H
  #define __ARCH_ARM_SRC_STM32L4_STM32L4_QENCODER_H
  
  /************************************************************************************
   * Included Files
   ************************************************************************************/
  
  #include <tinyara/config.h>
  
  #include "chip.h"
  
  #ifdef CONFIG_SENSORS_QENCODER
  
  /************************************************************************************
   * Included Files
   ************************************************************************************/
  /* Timer devices may be used for different purposes.  One special purpose is as
   * a quadrature encoder input device.  If CONFIG_STM32L4_TIMn is defined then the
   * CONFIG_STM32L4_TIMn_QE must also be defined to indicate that timer "n" is intended
   * to be used for as a quadrature encoder.
   */
  
  #ifndef CONFIG_STM32L4_TIM1
  #  undef CONFIG_STM32L4_TIM1_QE
  #endif
  #ifndef CONFIG_STM32L4_TIM2
  #  undef CONFIG_STM32L4_TIM2_QE
  #endif
  #ifndef CONFIG_STM32L4_TIM3
  #  undef CONFIG_STM32L4_TIM3_QE
  #endif
  #ifndef CONFIG_STM32L4_TIM4
  #  undef CONFIG_STM32L4_TIM4_QE
  #endif
  #ifndef CONFIG_STM32L4_TIM5
  #  undef CONFIG_STM32L4_TIM5_QE
  #endif
  #ifndef CONFIG_STM32L4_TIM8
  #  undef CONFIG_STM32L4_TIM8_QE
  #endif
  
  /* Only timers 2-5, and 1 & 8 can be used as a quadrature encoder
   */
  
  #undef CONFIG_STM32L4_TIM6_QE
  #undef CONFIG_STM32L4_TIM7_QE
  #undef CONFIG_STM32L4_TIM9_QE
  #undef CONFIG_STM32L4_TIM10_QE
  #undef CONFIG_STM32L4_TIM11_QE
  #undef CONFIG_STM32L4_TIM12_QE
  #undef CONFIG_STM32L4_TIM13_QE
  #undef CONFIG_STM32L4_TIM14_QE
  
  /* Clock out frequency.  This value is used to calculation the timer CLKIN in
   * prescaler value.
   */
  
  #ifndef CONFIG_STM32L4_TIM1_QECLKOUT
  #  define CONFIG_STM32L4_TIM1_QECLKOUT 28000000
  #endif
  
  #ifndef CONFIG_STM32L4_TIM2_QECLKOUT
  #  define CONFIG_STM32L4_TIM2_QECLKOUT 28000000
  #endif
  
  #ifndef CONFIG_STM32L4_TIM3_QECLKOUT
  #  define CONFIG_STM32L4_TIM3_QECLKOUT 28000000
  #endif
  
  #ifndef CONFIG_STM32L4_TIM4_QECLKOUT
  #  define CONFIG_STM32L4_TIM4_QECLKOUT 28000000
  #endif
  
  #ifndef CONFIG_STM32L4_TIM5_QECLKOUT
  #  define CONFIG_STM32L4_TIM5_QECLKOUT 28000000
  #endif
  
  #ifndef CONFIG_STM32L4_TIM8_QECLKOUT
  #  define CONFIG_STM32L4_TIM8_QECLKOUT 28000000
  #endif
  
  /************************************************************************************
   * Included Files
   ************************************************************************************/
  
  /************************************************************************************
   * Name: stm32l4_qeinitialize
   *
   * Description:
   *   Initialize a quadrature encoder interface.  This function must be called from
   *   board-specific logic..
   *
   * Input Parameters:
   *   devpath - The full path to the driver to register. E.g., "/dev/qe0"
   *   tim     - The timer number to used.  'tim' must be an element of {1,2,3,4,5,8}
   *
   * Returned Value:
   *   Zero on success; A negated errno value is returned on failure.
   *
   ************************************************************************************/
  
  int stm32l4_qeinitialize(FAR const char *devpath, int tim);
  
  #endif /* CONFIG_SENSORS_QENCODER */
  #endif /* __ARCH_ARM_SRC_STM32L4_STM32L4_QENCODER_H */
  
  