Nordic stack and drivers for the mbed BLE API
Dependents: BLE_ANCS_SDAPI BLE_temperature BLE_HeartRate writable_gatt ... more
Diff: TARGET_MCU_NRF51822/sdk/source/libraries/scheduler/app_scheduler.c
- Revision:
- 638:c90ae1400bf2
diff -r f7faad332abc -r c90ae1400bf2 TARGET_MCU_NRF51822/sdk/source/libraries/scheduler/app_scheduler.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/TARGET_MCU_NRF51822/sdk/source/libraries/scheduler/app_scheduler.c Wed Sep 14 14:39:43 2016 +0100 @@ -0,0 +1,212 @@ +/* + * Copyright (c) Nordic Semiconductor ASA + * 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 Nordic Semiconductor ASA nor the names of other + * contributors to this software 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 "app_scheduler.h" +#include <stdlib.h> +#include <stdint.h> +#include <string.h> +#include "nrf_soc.h" +#include "nrf_assert.h" +#include "app_util.h" +#include "app_util_platform.h" + +/**@brief Structure for holding a scheduled event header. */ +typedef struct +{ + app_sched_event_handler_t handler; /**< Pointer to event handler to receive the event. */ + uint16_t event_data_size; /**< Size of event data. */ +} event_header_t; + +STATIC_ASSERT(sizeof(event_header_t) <= APP_SCHED_EVENT_HEADER_SIZE); + +static event_header_t * m_queue_event_headers; /**< Array for holding the queue event headers. */ +static uint8_t * m_queue_event_data; /**< Array for holding the queue event data. */ +static volatile uint8_t m_queue_start_index; /**< Index of queue entry at the start of the queue. */ +static volatile uint8_t m_queue_end_index; /**< Index of queue entry at the end of the queue. */ +static uint16_t m_queue_event_size; /**< Maximum event size in queue. */ +static uint16_t m_queue_size; /**< Number of queue entries. */ + +/**@brief Function for incrementing a queue index, and handle wrap-around. + * + * @param[in] index Old index. + * + * @return New (incremented) index. + */ +static __INLINE uint8_t next_index(uint8_t index) +{ + return (index < m_queue_size) ? (index + 1) : 0; +} + + +static __INLINE uint8_t app_sched_queue_full() +{ + uint8_t tmp = m_queue_start_index; + return next_index(m_queue_end_index) == tmp; +} + +/**@brief Macro for checking if a queue is full. */ +#define APP_SCHED_QUEUE_FULL() app_sched_queue_full() + + +static __INLINE uint8_t app_sched_queue_empty() +{ + uint8_t tmp = m_queue_start_index; + return m_queue_end_index == tmp; +} + +/**@brief Macro for checking if a queue is empty. */ +#define APP_SCHED_QUEUE_EMPTY() app_sched_queue_empty() + + +uint32_t app_sched_init(uint16_t event_size, uint16_t queue_size, void * p_event_buffer) +{ + uint16_t data_start_index = (queue_size + 1) * sizeof(event_header_t); + + // Check that buffer is correctly aligned + if (!is_word_aligned(p_event_buffer)) + { + return NRF_ERROR_INVALID_PARAM; + } + + // Initialize event scheduler + m_queue_event_headers = p_event_buffer; + m_queue_event_data = &((uint8_t *)p_event_buffer)[data_start_index]; + m_queue_end_index = 0; + m_queue_start_index = 0; + m_queue_event_size = event_size; + m_queue_size = queue_size; + + return NRF_SUCCESS; +} + + +uint32_t app_sched_event_put(void * p_event_data, + uint16_t event_data_size, + app_sched_event_handler_t handler) +{ + uint32_t err_code; + + if (event_data_size <= m_queue_event_size) + { + uint16_t event_index = 0xFFFF; + + CRITICAL_REGION_ENTER(); + + if (!APP_SCHED_QUEUE_FULL()) + { + event_index = m_queue_end_index; + m_queue_end_index = next_index(m_queue_end_index); + } + + CRITICAL_REGION_EXIT(); + + if (event_index != 0xFFFF) + { + // NOTE: This can be done outside the critical region since the event consumer will + // always be called from the main loop, and will thus never interrupt this code. + m_queue_event_headers[event_index].handler = handler; + if ((p_event_data != NULL) && (event_data_size > 0)) + { + memcpy(&m_queue_event_data[event_index * m_queue_event_size], + p_event_data, + event_data_size); + m_queue_event_headers[event_index].event_data_size = event_data_size; + } + else + { + m_queue_event_headers[event_index].event_data_size = 0; + } + + err_code = NRF_SUCCESS; + } + else + { + err_code = NRF_ERROR_NO_MEM; + } + } + else + { + err_code = NRF_ERROR_INVALID_LENGTH; + } + + return err_code; +} + + +/**@brief Function for reading the next event from specified event queue. + * + * @param[out] pp_event_data Pointer to pointer to event data. + * @param[out] p_event_data_size Pointer to size of event data. + * @param[out] p_event_handler Pointer to event handler function pointer. + * + * @return NRF_SUCCESS if new event, NRF_ERROR_NOT_FOUND if event queue is empty. + */ +static uint32_t app_sched_event_get(void ** pp_event_data, + uint16_t * p_event_data_size, + app_sched_event_handler_t * p_event_handler) +{ + uint32_t err_code = NRF_ERROR_NOT_FOUND; + + if (!APP_SCHED_QUEUE_EMPTY()) + { + uint16_t event_index; + + // NOTE: There is no need for a critical region here, as this function will only be called + // from app_sched_execute() from inside the main loop, so it will never interrupt + // app_sched_event_put(). Also, updating of (i.e. writing to) the start index will be + // an atomic operation. + event_index = m_queue_start_index; + m_queue_start_index = next_index(m_queue_start_index); + + *pp_event_data = &m_queue_event_data[event_index * m_queue_event_size]; + *p_event_data_size = m_queue_event_headers[event_index].event_data_size; + *p_event_handler = m_queue_event_headers[event_index].handler; + + err_code = NRF_SUCCESS; + } + + return err_code; +} + + +void app_sched_execute(void) +{ + void * p_event_data; + uint16_t event_data_size; + app_sched_event_handler_t event_handler; + + // Get next event (if any), and execute handler + while ((app_sched_event_get(&p_event_data, &event_data_size, &event_handler) == NRF_SUCCESS)) + { + event_handler(p_event_data, event_data_size); + } +}