InterruptManager.cpp

00001 #include "cmsis.h"
00002 #if defined(NVIC_NUM_VECTORS)
00003 
00004 #include "InterruptManager.h"
00005 #include <string.h>
00006 
00007 #define CHAIN_INITIAL_SIZE    4
00008 
00009 namespace mbed {
00010 
00011 typedef void (*pvoidf)(void);
00012 
00013 InterruptManager* InterruptManager::_instance = (InterruptManager*)NULL;
00014 
00015 InterruptManager* InterruptManager::get() {
00016     if (NULL == _instance)
00017         _instance = new InterruptManager();
00018     return _instance;
00019 }
00020 
00021 InterruptManager::InterruptManager() {
00022     memset(_chains, 0, NVIC_NUM_VECTORS * sizeof(CallChain*));
00023 }
00024 
00025 void InterruptManager::destroy() {
00026     // Not a good idea to call this unless NO interrupt at all
00027     // is under the control of the handler; otherwise, a system crash
00028     // is very likely to occur
00029     if (NULL != _instance) {
00030         delete _instance;
00031         _instance = (InterruptManager*)NULL;
00032     }
00033 }
00034 
00035 InterruptManager::~InterruptManager() {
00036     for(int i = 0; i < NVIC_NUM_VECTORS; i++)
00037         if (NULL != _chains[i])
00038             delete _chains[i];
00039 }
00040 
00041 bool InterruptManager::must_replace_vector(IRQn_Type irq) {
00042     int irq_pos = get_irq_index(irq);
00043 
00044     if (NULL == _chains[irq_pos]) {
00045         _chains[irq_pos] = new CallChain(CHAIN_INITIAL_SIZE);
00046         _chains[irq_pos]->add((pvoidf)NVIC_GetVector(irq));
00047         return true;
00048     }
00049     return false;
00050 }
00051 
00052 pFunctionPointer_t InterruptManager::add_common(void (*function)(void), IRQn_Type irq, bool front) {
00053     int irq_pos = get_irq_index(irq);
00054     bool change = must_replace_vector(irq);
00055 
00056     pFunctionPointer_t pf = front ? _chains[irq_pos]->add_front(function) : _chains[irq_pos]->add(function);
00057     if (change)
00058         NVIC_SetVector(irq, (uint32_t)&InterruptManager::static_irq_helper);
00059     return pf;
00060 }
00061 
00062 bool InterruptManager::remove_handler(pFunctionPointer_t  handler, IRQn_Type irq) {
00063     int irq_pos = get_irq_index(irq);
00064 
00065     if (NULL == _chains[irq_pos])
00066         return false;
00067     if (!_chains[irq_pos]->remove(handler))
00068         return false;
00069     // If there's a single function left in the chain, swith the interrupt vector
00070     // to call that function directly. This way we save both time and space.
00071     if (_chains[irq_pos]->size() == 1 && NULL != _chains[irq_pos]->get(0)->get_function()) {
00072         NVIC_SetVector(irq, (uint32_t)_chains[irq_pos]->get(0)->get_function());
00073         delete _chains[irq_pos];
00074         _chains[irq_pos] = (CallChain*) NULL;
00075     }
00076     return true;
00077 }
00078 
00079 void InterruptManager::irq_helper() {
00080     _chains[__get_IPSR()]->call();
00081 }
00082 
00083 int InterruptManager::get_irq_index(IRQn_Type irq) {
00084     return (int)irq + NVIC_USER_IRQ_OFFSET;
00085 }
00086 
00087 void InterruptManager::static_irq_helper() {
00088     InterruptManager::get()->irq_helper();
00089 }
00090 
00091 } // namespace mbed
00092 
00093 #endif