/**************************************************************************** * arch/arm/src/samv7/sam_oneshot.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_SAMV7_SAM_ONESHOT_H #define __ARCH_ARM_SRC_SAMV7_SAM_ONESHOT_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include "sam_tc.h" #ifdef CONFIG_SAMV7_ONESHOT /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define ONESHOT_INITIALIZED(s) (((s)->tch) != NULL) /**************************************************************************** * Public Types ****************************************************************************/ /* 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 * sam_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 sam_oneshot_s { uint8_t chan; /* The timer/counter in use */ volatile bool running; /* True: the timer is running */ TC_HANDLE tch; /* Handle returned by * sam_tc_initialize() */ volatile oneshot_handler_t handler; /* Oneshot expiration callback */ volatile void *arg; /* The argument that will accompany * the callback */ #ifdef CONFIG_SAMV7_FREERUN volatile uint16_t start_count; /* Stores the value of the freerun counter, * at each start of the oneshot timer. Is necessary * to find out if the oneshot counter was updated * correctly at the time of the call to * sam_oneshot_cancel or not. */ #endif }; /**************************************************************************** * Public Data ****************************************************************************/ #undef EXTERN #if defined(__cplusplus) #define EXTERN extern "C" extern "C" { #else #define EXTERN extern #endif /**************************************************************************** * Public Function Prototypes ****************************************************************************/ /**************************************************************************** * Name: sam_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. See the TC_CHAN* * definitions in arch/arm/src/samv7/sam_tc.h. * 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 sam_oneshot_initialize(struct sam_oneshot_s *oneshot, int chan, uint16_t resolution); /**************************************************************************** * Name: sam_oneshot_max_delay * * Description: * Return the maximum delay supported by the one shot timer (in * microseconds). * * Input Parameters: * oneshot Caller allocated instance of the oneshot state structure. This * structure must have been previously initialized via a call to * sam_oneshot_initialize(); * usec The location in which to return the maximum delay. * * Returned Value: * Zero (OK) is returned on success; a negated errno value is returned * on failure. * ****************************************************************************/ int sam_oneshot_max_delay(struct sam_oneshot_s *oneshot, uint64_t *usec); /**************************************************************************** * Name: sam_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 * sam_oneshot_initialize(); * freerun Caller allocated instance of the freerun state structure. This * structure must have been previously initialized via a call to * sam_freerun_initialize(). May be NULL if there is no matching * free-running timer. * 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. * ****************************************************************************/ struct sam_freerun_s; int sam_oneshot_start(struct sam_oneshot_s *oneshot, struct sam_freerun_s *freerun, oneshot_handler_t handler, void *arg, const struct timespec *ts); /**************************************************************************** * Name: sam_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 * sam_oneshot_initialize(); * freerun Caller allocated instance of the freerun state structure. This * structure must have been previously initialized via a call to * sam_freerun_initialize(). May be NULL if there is no matching * free-running timer. * 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. * ****************************************************************************/ struct sam_freerun_s; int sam_oneshot_cancel(struct sam_oneshot_s *oneshot, struct sam_freerun_s *freerun, struct timespec *ts); #undef EXTERN #ifdef __cplusplus } #endif #endif /* CONFIG_SAMV7_ONESHOT */ #endif /* __ARCH_ARM_SRC_SAMV7_SAM_ONESHOT_H */