ecl_timer.c

00001 /******************************************************************************
00002 The MIT License(MIT)
00003 
00004 Embedded Template Library.
00005 https://github.com/ETLCPP/etl
00006 https://www.etlcpp.com
00007 
00008 Copyright(c) 2017 jwellbelove
00009 
00010 Permission is hereby granted, free of charge, to any person obtaining a copy
00011 of this software and associated documentation files(the "Software"), to deal
00012 in the Software without restriction, including without limitation the rights
00013 to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
00014 copies of the Software, and to permit persons to whom the Software is
00015 furnished to do so, subject to the following conditions :
00016 
00017 The above copyright notice and this permission notice shall be included in all
00018 copies or substantial portions of the Software.
00019 
00020 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00021 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00022 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
00023 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00024 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00025 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00026 SOFTWARE.
00027 ******************************************************************************/
00028 
00029 #include <stdint.h>
00030 #include <assert.h>
00031 
00032 #include "ecl_timer.h"
00033 
00034 //*****************************************************************************
00035 // Internal timer list
00036 //*****************************************************************************
00037 
00038 static ecl_timer_id_t head;
00039 static ecl_timer_id_t tail;
00040 static ecl_timer_id_t current;
00041 
00042 static struct ecl_timer_config* ptimers;
00043 
00044 static void ecl_timer_list_init(struct ecl_timer_config* const ptimers_)
00045 {
00046   ptimers = ptimers_;
00047   head    = ECL_TIMER_NO_TIMER;
00048   tail    = ECL_TIMER_NO_TIMER;
00049   current = ECL_TIMER_NO_TIMER;
00050 }
00051 
00052 //*******************************
00053 static struct ecl_timer_config* ecl_timer_list_front()
00054 {
00055   return &ptimers[head];
00056 }
00057 
00058 //*******************************
00059 static ecl_timer_id_t ecl_timer_list_begin()
00060 {
00061   current = head;
00062   return current;
00063 }
00064 
00065 //*******************************
00066 static ecl_timer_id_t ecl_timer_list_next(ecl_timer_id_t last)
00067 {
00068   current = ptimers[last].next;
00069   return current;
00070 }
00071 
00072 //*******************************
00073 static int ecl_timer_list_empty()
00074 {
00075   return head == ECL_TIMER_NO_TIMER;
00076 }
00077 
00078 //*******************************
00079 // Inserts the timer at the correct delta position
00080 //*******************************
00081 static void ecl_timer_list_insert(ecl_timer_id_t id_)
00082 {
00083   struct ecl_timer_config* ptimer = &ptimers[id_];
00084 
00085   if (head == ECL_TIMER_NO_TIMER)
00086   {
00087     // No entries yet.
00088     head = id_;
00089     tail = id_;
00090     ptimer->previous = ECL_TIMER_NO_TIMER;
00091     ptimer->next     = ECL_TIMER_NO_TIMER;
00092   }
00093   else
00094   {
00095     // We already have entries.
00096     ecl_timer_id_t test_id = ecl_timer_list_begin();
00097 
00098     while (test_id != ECL_TIMER_NO_TIMER)
00099     {
00100       struct ecl_timer_config* ptest = &ptimers[test_id];
00101 
00102       // Find the correct place to insert.
00103       if (ptimer->delta <= ptest->delta)
00104       {
00105         if (ptest->id == head)
00106         {
00107           head = ptimer->id;
00108         }
00109 
00110         // Insert before ptest->
00111         ptimer->previous = ptest->previous;
00112         ptest->previous = ptimer->id;
00113         ptimer->next = ptest->id;
00114 
00115         // Adjust the next delta to compensate.
00116         ptest->delta -= ptimer->delta;
00117 
00118         if (ptimer->previous != ECL_TIMER_NO_TIMER)
00119         {
00120           ptimers[ptimer->previous].next = ptimer->id;
00121         }
00122         break;
00123       }
00124       else
00125       {
00126         ptimer->delta -= ptest->delta;
00127       }
00128 
00129       test_id = ecl_timer_list_next(test_id);
00130     }
00131 
00132     // Reached the end?
00133     if (test_id == ECL_TIMER_NO_TIMER)
00134     {
00135       // Tag on to the tail.
00136       ptimers[tail].next = ptimer->id;
00137       ptimer->previous   = tail;
00138       ptimer->next       = ECL_TIMER_NO_TIMER;
00139       tail               = ptimer->id;
00140     }
00141   }
00142 }
00143 
00144 //*******************************
00145 static void ecl_timer_list_remove(ecl_timer_id_t id_, int has_expired)
00146 {
00147   struct ecl_timer_config* ptimer = &ptimers[id_];
00148 
00149   if (head == id_)
00150   {
00151     head = ptimer->next;
00152   }
00153   else
00154   {
00155     ptimers[ptimer->previous].next = ptimer->next;
00156   }
00157 
00158   if (tail == id_)
00159   {
00160     tail = ptimer->previous;
00161   }
00162   else
00163   {
00164     ptimers[ptimer->next].previous = ptimer->previous;
00165   }
00166 
00167   if (!has_expired)
00168   {
00169     // Adjust the next delta.
00170     if (ptimer->next != ECL_TIMER_NO_TIMER)
00171     {
00172       ptimers[ptimer->next].delta += ptimer->delta;
00173     }
00174   }
00175 
00176   ptimer->previous = ECL_TIMER_NO_TIMER;
00177   ptimer->next     = ECL_TIMER_NO_TIMER;
00178   ptimer->delta    = ECL_TIMER_INACTIVE;
00179 }
00180 
00181 //*******************************
00182 static void ecl_timer_list_clear()
00183 {
00184   ecl_timer_id_t id = ecl_timer_list_begin();
00185 
00186   while (id != ECL_TIMER_NO_TIMER)
00187   {
00188     struct ecl_timer_config* ptimer = &ptimers[id];
00189     id = ecl_timer_list_next(id);
00190     ptimer->next = ECL_TIMER_NO_TIMER;
00191   }
00192 
00193   head = ECL_TIMER_NO_TIMER;
00194   tail = ECL_TIMER_NO_TIMER;
00195   current = ECL_TIMER_NO_TIMER;
00196 }
00197 
00198 //*****************************************************************************
00199 // Timer Framework
00200 //*****************************************************************************
00201 
00202 //*******************************************
00203 /// Default initialisation.
00204 //*******************************************
00205 void ecl_timer_data_init_default(struct ecl_timer_config* ptimer_data_)
00206 {
00207   assert(ptimer_data_ != 0);
00208 
00209   ptimer_data_->pcallback = 0;
00210   ptimer_data_->period    = 0;
00211   ptimer_data_->delta     = ECL_TIMER_INACTIVE;
00212   ptimer_data_->id        = ECL_TIMER_NO_TIMER;
00213   ptimer_data_->previous  = ECL_TIMER_NO_TIMER;
00214   ptimer_data_->next      = ECL_TIMER_NO_TIMER;
00215   ptimer_data_->repeating = ECL_TIMER_REPEATING;
00216 }
00217 
00218 //*******************************************
00219 /// Parameterised initialisation.
00220 //*******************************************
00221 void ecl_timer_data_init(struct ecl_timer_config* ptimer_data_,
00222                          ecl_timer_id_t               id_,
00223                          void                   (*pcallback_)(),
00224                          ecl_timer_time_t             period_,
00225                          ecl_timer_mode_t             repeating_)
00226 {
00227   assert(ptimer_data_ != 0);
00228   assert(pcallback_   != 0);
00229 
00230   ptimer_data_->pcallback = pcallback_;
00231   ptimer_data_->period    = period_;
00232   ptimer_data_->delta     = ECL_TIMER_INACTIVE;
00233   ptimer_data_->id        = id_;
00234   ptimer_data_->previous  = ECL_TIMER_NO_TIMER;
00235   ptimer_data_->next      = ECL_TIMER_NO_TIMER;
00236   ptimer_data_->repeating = repeating_;
00237 }
00238 
00239 //*******************************************
00240 /// Returns true if the timer is active.
00241 //*******************************************
00242 ecl_timer_result_t ecl_timer_is_active(struct ecl_timer_config* ptimer_data_)
00243 {
00244   assert(ptimer_data_ != 0);
00245 
00246   return (ptimer_data_->delta != ECL_TIMER_INACTIVE) ? ECL_TIMER_PASS : ECL_TIMER_FAIL;
00247 }
00248 
00249 //*******************************************
00250 /// Sets the timer to the inactive state.
00251 //*******************************************
00252 void ecl_set_timer_inactive(struct ecl_timer_config* ptimer_data_)
00253 {
00254   assert(ptimer_data_ != 0);
00255 
00256   ptimer_data_->delta = ECL_TIMER_INACTIVE;
00257 }
00258 
00259 struct ecl_time_config
00260 {
00261   struct ecl_timer_config* ptimers;
00262   uint_least8_t max_timers;
00263   volatile ecl_timer_enable_t enabled;
00264   ECL_TIMER_TIMER_SEMAPHORE process_semaphore;
00265   volatile uint_least8_t registered_timers;
00266 };
00267 
00268 static struct ecl_time_config ecl;
00269 
00270 void ecl_timer_init(struct ecl_timer_config* ptimers_, uint_least8_t max_timers_)
00271 {
00272   assert(ptimers_ != 0);
00273 
00274   ecl.ptimers           = ptimers_;
00275   ecl.max_timers        = max_timers_;
00276   ecl.enabled           = 0;
00277   ecl.process_semaphore = 0;
00278   ecl.registered_timers = 0;
00279 
00280   int i;
00281   for (i = 0; i < max_timers_; ++i)
00282   {
00283     ecl_timer_data_init_default(&ecl.ptimers[i]);
00284   }
00285 
00286   ecl_timer_list_init(ecl.ptimers);
00287 }
00288 
00289 //*******************************************
00290 /// Register a ptimer->
00291 //*******************************************
00292 ecl_timer_id_t ecl_timer_register(void             (*pcallback_)(),
00293                                   ecl_timer_time_t period_,
00294                                   ecl_timer_mode_t repeating_)
00295 {
00296   assert(pcallback_ != 0);
00297   assert(ecl.ptimers != 0);
00298 
00299   ecl_timer_id_t id = ECL_TIMER_NO_TIMER;
00300 
00301   ECL_TIMER_DISABLE_PROCESSING(ecl.process_semaphore);
00302 
00303   int is_space = (ecl.registered_timers < ecl.max_timers);
00304 
00305   if (is_space)
00306   {
00307     // Search for the free space.
00308     uint_least8_t i;
00309     for (i = 0; i < ecl.max_timers; ++i)
00310     {
00311       struct ecl_timer_config* ptimer = &ecl.ptimers[i];
00312 
00313       if (ptimer->id == ECL_TIMER_NO_TIMER)
00314       {
00315         // Create in-place.
00316         ecl_timer_data_init(ptimer, i, pcallback_, period_, repeating_);
00317         ++ecl.registered_timers;
00318         id = i;
00319         break;
00320       }
00321     }
00322   }
00323 
00324   ECL_TIMER_ENABLE_PROCESSING(ecl.process_semaphore);
00325 
00326   return id;
00327 }
00328 
00329 //*******************************************
00330 /// Unregister a ptimer->
00331 //*******************************************
00332 ecl_timer_result_t ecl_timer_unregister(ecl_timer_id_t id_)
00333 {
00334   assert(ecl.ptimers != 0);
00335   
00336   ecl_timer_result_t result = ECL_TIMER_FAIL;
00337 
00338   if (id_ != ECL_TIMER_NO_TIMER)
00339   {
00340     ECL_TIMER_DISABLE_PROCESSING(ecl.process_semaphore);
00341 
00342     struct ecl_timer_config* ptimer = &ecl.ptimers[id_];
00343 
00344     if (ptimer->id != ECL_TIMER_NO_TIMER)
00345     {
00346       if (ecl_timer_is_active(ptimer))
00347       {
00348         ecl_timer_list_remove(ptimer->id, 0);
00349 
00350         // Reset in-place.
00351         ecl_timer_data_init_default(ptimer);
00352         --ecl.registered_timers;
00353 
00354         result = ECL_TIMER_PASS;
00355       }
00356     }
00357 
00358     ECL_TIMER_ENABLE_PROCESSING(ecl.process_semaphore);
00359   }
00360 
00361   return result;
00362 }
00363 
00364 //*******************************************
00365 /// Enable/disable the ptimer->
00366 //*******************************************
00367 void ecl_timer_enable(ecl_timer_enable_t state_)
00368 {
00369   assert(ecl.ptimers != 0);
00370   assert((state_ == ECL_TIMER_ENABLED) || (state_ == ECL_TIMER_DISABLED));
00371 
00372   ecl.enabled = state_;
00373 }
00374 
00375 //*******************************************
00376 /// Get the enable/disable state.
00377 //*******************************************
00378 ecl_timer_result_t ecl_timer_is_running()
00379 {
00380   return ecl.enabled;
00381 }
00382 
00383 //*******************************************
00384 /// Clears the timer of data.
00385 //*******************************************
00386 void ecl_timer_clear()
00387 { 
00388   ECL_TIMER_DISABLE_PROCESSING(ecl.process_semaphore);
00389 
00390   ecl_timer_list_clear();
00391 
00392   int i;
00393   for (i = 0; i < ecl.max_timers; ++i)
00394   {
00395     ecl_timer_data_init_default(&ecl.ptimers[i]);
00396   }
00397 
00398   ecl.registered_timers = 0;
00399 
00400   ECL_TIMER_ENABLE_PROCESSING(ecl.process_semaphore);
00401 }
00402 
00403 //*******************************************
00404 // Called by the timer service to indicate the
00405 // amount of time that has elapsed since the last successful call to 'tick'.
00406 // Returns true if the tick was processed, false if not.
00407 //*******************************************
00408 ecl_timer_result_t ecl_timer_tick(uint32_t count)
00409 {
00410   assert(ecl.ptimers != 0);
00411   
00412   if (ecl.enabled)
00413   {
00414     if (ECL_TIMER_PROCESSING_ENABLED(ecl.process_semaphore))
00415     {
00416       // We have something to do?
00417       int has_active = !ecl_timer_list_empty();
00418 
00419       if (has_active)
00420       {
00421         while (has_active && (count >= ecl_timer_list_front()->delta))
00422         {
00423           struct ecl_timer_config* ptimer = ecl_timer_list_front();
00424 
00425           count -= ptimer->delta;
00426 
00427           ecl_timer_list_remove(ptimer->id, 1);
00428 
00429           if (ptimer->repeating)
00430           {
00431             // Reinsert the ptimer->
00432             ptimer->delta = ptimer->period;
00433             ecl_timer_list_insert(ptimer->id);
00434           }
00435 
00436           if (ptimer->pcallback != 0)
00437           {
00438             // Call the C callback.
00439             (ptimer->pcallback)();
00440           }
00441 
00442           has_active = !ecl_timer_list_empty();
00443         }
00444 
00445         if (has_active)
00446         {
00447           // Subtract any remainder from the next due timeout.
00448           ecl_timer_list_front()->delta -= count;
00449         }
00450       }
00451 
00452       return ECL_TIMER_PASS;
00453     }
00454   }
00455 
00456   return ECL_TIMER_FAIL;
00457 }
00458 
00459 //*******************************************
00460 /// Starts a timer
00461 //*******************************************
00462 ecl_timer_result_t ecl_timer_start(ecl_timer_id_t id_, ecl_timer_start_t immediate_)
00463 {
00464   assert(ecl.ptimers != 0);
00465   
00466   ECL_TIMER_DISABLE_PROCESSING(ecl.process_semaphore);
00467 
00468   ecl_timer_result_t result = ECL_TIMER_FAIL;
00469 
00470   // Valid timer id?
00471   if (id_ != ECL_TIMER_NO_TIMER)
00472   {
00473     struct ecl_timer_config* ptimer = &ecl.ptimers[id_];
00474 
00475     // Registered timer?
00476     if (ptimer->id != ECL_TIMER_NO_TIMER)
00477     {
00478       // Has a valid period.
00479       if (ptimer->period != ECL_TIMER_INACTIVE)
00480       {
00481         if (ecl_timer_is_active(ptimer))
00482         {
00483           ecl_timer_list_remove(ptimer->id, 0);
00484         }
00485 
00486         ptimer->delta = immediate_ ? 0 : ptimer->period;
00487         ecl_timer_list_insert(ptimer->id);
00488 
00489         result = ECL_TIMER_PASS;
00490       }
00491     }
00492   }
00493 
00494   ECL_TIMER_ENABLE_PROCESSING(ecl.process_semaphore);
00495 
00496   return result;
00497 }
00498 
00499 //*******************************************
00500 /// Stops a timer
00501 //*******************************************
00502 ecl_timer_result_t ecl_timer_stop(ecl_timer_id_t id_)
00503 {
00504   assert(ecl.ptimers != 0);
00505   
00506   ECL_TIMER_DISABLE_PROCESSING(ecl.process_semaphore);
00507 
00508   ecl_timer_result_t result = ECL_TIMER_FAIL;
00509 
00510   // Valid timer id?
00511   if (id_ != ECL_TIMER_NO_TIMER)
00512   {
00513     struct ecl_timer_config* ptimer = &ecl.ptimers[id_];
00514 
00515     // Registered timer?
00516     if (ptimer->id != ECL_TIMER_NO_TIMER)
00517     {
00518       if (ecl_timer_is_active(ptimer))
00519       {
00520         ecl_timer_list_remove(ptimer->id, 0);
00521         result = ECL_TIMER_PASS;
00522       }
00523     }
00524   }
00525 
00526   ECL_TIMER_ENABLE_PROCESSING(ecl.process_semaphore);
00527 
00528   return result;
00529 }
00530 
00531 //*******************************************
00532 /// Sets a timer's period.
00533 //*******************************************
00534 ecl_timer_result_t ecl_timer_set_period(ecl_timer_id_t id_, ecl_timer_time_t period_)
00535 {
00536   assert(ecl.ptimers != 0);
00537   
00538   if (ecl_timer_stop(id_))
00539   {
00540     ecl.ptimers[id_].period = period_;
00541     return ecl_timer_start(id_, 0);
00542   }
00543 
00544   return ECL_TIMER_FAIL;
00545 }
00546 
00547 //*******************************************
00548 /// Sets a timer's mode.
00549 //*******************************************
00550 ecl_timer_result_t ecl_timer_set_mode(ecl_timer_id_t id_, ecl_timer_mode_t repeating_)
00551 {
00552   assert(ecl.ptimers != 0);
00553   
00554   if (ecl_timer_stop(id_))
00555   {
00556     ecl.ptimers[id_].repeating = repeating_;
00557     return ecl_timer_start(id_, 0);
00558   }
00559 
00560   return ECL_TIMER_FAIL;
00561 }
00562 
00563 
00564 
00565 
00566