text: /****************************************************************************
   * arch/risc-v/src/bl602/bl602_oneshot_lowerhalf.h
   *
   * 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.
   *
   ****************************************************************************/
  
  #ifndef __ARCH_ARM_SRC_BL602_ONESHOT_H
  #define __ARCH_ARM_SRC_BL602_ONESHOT_H
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <stdint.h>
  #include <time.h>
  
  #include <nuttx/irq.h>
  
  #include "bl602_tim_lowerhalf.h"
  
  #ifdef CONFIG_BL602_ONESHOT
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  #if !defined(CONFIG_BL602_ONESHOT_MAXTIMERS) || \
    CONFIG_BL602_ONESHOT_MAXTIMERS < 1
  #undef CONFIG_BL602_ONESHOT_MAXTIMERS
  #define CONFIG_BL602_ONESHOT_MAXTIMERS 1
  #endif
  
  #if CONFIG_BL602_ONESHOT_MAXTIMERS > 8
  #warning Additional logic required to handle more than 8 timers
  #undef CONFIG_BL602_ONESHOT_MAXTIMERS
  #define CONFIG_BL602_ONESHOT_MAXTIMERS 8
  #endif
  
  /****************************************************************************
   * Public Types
   ****************************************************************************/
  
  #ifndef __ASSEMBLY__
  /* This describes the callback function that will be invoked when the oneshot
   * timer expires.  The oneshot fires, the client will receive:
   *
   *   arg - The opaque argument provided when the interrupt was registered
   */
  
  typedef void (*oneshot_handler_t)(void *arg);
  
  /* The oneshot client must allocate an instance of this structure and called
   * bl602_oneshot_initialize() before using the oneshot facilities.  The
   * client should not access the contents of this structure directly since
   * the contents are subject to change.
   */
  
  struct bl602_oneshot_s
  {
    uint8_t chan; /* The timer/counter in use */
  #if CONFIG_BL602_ONESHOT_MAXTIMERS > 1
    uint8_t cbndx; /* Timer callback handler index */
  #endif
    volatile bool               running; /* True: the timer is running */
    FAR struct bl602_tim_dev_s *tch;     /* Pointer returned by
                                          * bl602_tim_init() */
    volatile oneshot_handler_t handler;  /* Oneshot expiration callback */
    volatile void *            arg;      /* The argument that will accompany
                                          * the callback */
    uint32_t frequency;
    uint32_t period;
  };
  
  /****************************************************************************
   * Public Data
   ****************************************************************************/
  
  #undef EXTERN
  #if defined(__cplusplus)
  #define EXTERN extern "C"
  extern "C"
  {
  #else
  #define EXTERN extern
  #endif
  
  /****************************************************************************
   * Public Function Prototypes
   ****************************************************************************/
  
  /****************************************************************************
   * Name: bl602_oneshot_initialize
   *
   * Description:
   *   Initialize the oneshot timer wrapper
   *
   * Input Parameters:
   *   oneshot    Caller allocated instance of the oneshot state structure
   *   chan       Timer counter channel to be used.
   *   resolution The required resolution of the timer in units of
   *              microseconds.  NOTE that the range is restricted to the
   *              range of uint16_t (excluding zero).
   *
   * Returned Value:
   *   Zero (OK) is returned on success; a negated errno value is returned
   *   on failure.
   *
   ****************************************************************************/
  
  int bl602_oneshot_initialize(struct bl602_oneshot_s *oneshot,
                               int                     chan,
                               uint16_t                resolution);
  
  /****************************************************************************
   * Name: bl602_oneshot_max_delay
   *
   * Description:
   *   Determine the maximum delay of the one-shot timer (in microseconds)
   *
   ****************************************************************************/
  
  int bl602_oneshot_max_delay(struct bl602_oneshot_s *oneshot, uint64_t *usec);
  
  /****************************************************************************
   * Name: bl602_oneshot_start
   *
   * Description:
   *   Start the oneshot timer
   *
   * Input Parameters:
   *   oneshot Caller allocated instance of the oneshot state structure.  This
   *           structure must have been previously initialized via a call to
   *           bl602_oneshot_initialize();
   *   handler The function to call when when the oneshot timer expires.
   *   arg     An opaque argument that will accompany the callback.
   *   ts      Provides the duration of the one shot timer.
   *
   * Returned Value:
   *   Zero (OK) is returned on success; a negated errno value is returned
   *   on failure.
   *
   ****************************************************************************/
  
  int bl602_oneshot_start(struct bl602_oneshot_s *oneshot,
                          oneshot_handler_t       handler,
                          void *                  arg,
                          const struct timespec * ts);
  
  /****************************************************************************
   * Name: bl602_oneshot_cancel
   *
   * Description:
   *   Cancel the oneshot timer and return the time remaining on the timer.
   *
   *   NOTE: This function may execute at a high rate with no timer running (as
   *   when pre-emption is enabled and disabled).
   *
   * Input Parameters:
   *   oneshot Caller allocated instance of the oneshot state structure.  This
   *           structure must have been previously initialized via a call to
   *           bl602_oneshot_initialize();
   *   ts      The location in which to return the time remaining on the
   *           oneshot timer.  A time of zero is returned if the timer is
   *           not running.
   *
   * Returned Value:
   *   Zero (OK) is returned on success.  A call to up_timer_cancel() when
   *   the timer is not active should also return success; a negated errno
   *   value is returned on any failure.
   *
   ****************************************************************************/
  
  int bl602_oneshot_cancel(struct bl602_oneshot_s *oneshot,
                           struct timespec *       ts);
  
  #undef EXTERN
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* __ASSEMBLY__ */
  #endif /* CONFIG_BL602_ONESHOT */
  #endif /* __ARCH_ARM_SRC_BL602_ONESHOT_H */
  