mbed w/ spi bug fig
Fork of mbed-src by
capi/us_ticker_api.c
- Committer:
- emilmont
- Date:
- 2013-03-13
- Revision:
- 4:c4bfb462ca53
- Child:
- 6:6dfdb79ccc45
File content as of revision 4:c4bfb462ca53:
/* mbed Microcontroller Library * Copyright (c) 2006-2013 ARM Limited * * 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. */ #include <stddef.h> #include "us_ticker_api.h" static ticker_event_handler event_handler; static ticker_event_t *head = NULL; void us_ticker_set_handler(ticker_event_handler handler) { us_ticker_init(); event_handler = handler; } void us_ticker_irq_handler(void) { us_ticker_clear_interrupt(); /* Go through all the pending TimerEvents */ while (1) { if (head == NULL) { // There are no more TimerEvents left, so disable matches. us_ticker_disable_interrupt(); return; } if ((int)(head->timestamp - us_ticker_read()) <= 0) { // This event was in the past: // point to the following one and execute its handler ticker_event_t *p = head; head = head->next; if (event_handler != NULL) { event_handler(p->id); // NOTE: the handler can set new events } } else { // This event and the following ones in the list are in the future: // set it as next interrupt and return us_ticker_set_interrupt(head->timestamp); return; } } } void us_ticker_insert_event(ticker_event_t *obj, unsigned int timestamp, uint32_t id) { /* disable interrupts for the duration of the function */ __disable_irq(); // initialise our data obj->timestamp = timestamp; obj->id = id; /* Go through the list until we either reach the end, or find an element this should come before (which is possibly the head). */ ticker_event_t *prev = NULL, *p = head; while (p != NULL) { /* check if we come before p */ if ((int)(timestamp - p->timestamp) <= 0) { break; } /* go to the next element */ prev = p; p = p->next; } /* if prev is NULL we're at the head */ if (prev == NULL) { head = obj; us_ticker_set_interrupt(timestamp); } else { prev->next = obj; } /* if we're at the end p will be NULL, which is correct */ obj->next = p; __enable_irq(); } void us_ticker_remove_event(ticker_event_t *obj) { __disable_irq(); // remove this object from the list if (head == obj) { // first in the list, so just drop me head = obj->next; if (obj->next != NULL) { us_ticker_set_interrupt(head->timestamp); } } else { // find the object before me, then drop me ticker_event_t* p = head; while (p != NULL) { if (p->next == obj) { p->next = obj->next; break; } p = p->next; } } __enable_irq(); }