Add synchronous timer scheduler.

[bertos.git] / bertos / drv / timer.h

diff --git a/bertos/drv/timer.h b/bertos/drv/timer.h
index 0063ff4d606880ed69ccd3f2d124c1a30ba25c43..de2680093243d1b47d0ec5884b3c56c94cea13db 100644 (file)
--- a/bertos/drv/timer.h
+++ b/bertos/drv/timer.h
@@ -32,12 +32,22 @@
  *
  * \brief Hardware independent timer driver.
  *
+ * All timer related functions are implemented in this module. You have several options to use timers:
+ * \li simple delay: just use timer_delay() if you want to wait for a few milliseconds;
+ * \li delay with callback: create a timer structure and use timer_setDelay() and timer_setSoftint() to set the callback;
+ * \li delay with signal: same as above but use timer_setSignal() to set specify which signal to send.
+ * \li simple synchronous timer based scheduler: use synctimer_add() to schedule an event in a user provided queue.
+ *
+ * Whenever a timer expires you need to explicitly arm it again with timer_add(). If you want to abort a timer, use timer_abort().
+ * You can use conversion macros when using msecs to specify the delay.
+ *
  * \version $Id$
  * \author Bernie Innocenti <bernie@codewiz.org>
  *
  * $WIZ$ module_name = "timer"
  * $WIZ$ module_configuration = "bertos/cfg/cfg_timer.h"
- * $WIZ$ module_supports = "not atmega103"
+ * $WIZ$ module_depends = "event", "sysirq"
+ * $WIZ$ module_supports = "not atmega103 and not atmega8"
  */
 
 #ifndef DRV_TIMER_H
@@ -61,6 +71,8 @@
        #include CPU_HEADER(timer)
 #endif
 
+STATIC_ASSERT(sizeof(hptime_t) == SIZEOF_HPTIME_T);
+
 #include "cfg/cfg_timer.h"
 #include <cfg/debug.h>
 #include <cfg/compiler.h>
@@ -111,6 +123,7 @@ extern volatile ticks_t _clock;
  * \note This function must disable interrupts on 8/16bit CPUs because the
  * clock variable is larger than the processor word size and can't
  * be copied atomically.
+ * \sa timer_delay()
  */
 INLINE ticks_t timer_clock(void)
 {
@@ -202,6 +215,12 @@ INLINE utime_t hptime_to_us(hptime_t hpticks)
 }
 
 void timer_delayTicks(ticks_t delay);
+/**
+ * Wait some time [ms].
+ *
+ * \note CPU is released while waiting so you don't have to call cpu_relax() explicitly.
+ * \param delay Time to wait [ms].
+ */
 INLINE void timer_delay(mtime_t delay)
 {
        timer_delayTicks(ms_to_ticks(delay));
@@ -243,14 +262,23 @@ typedef struct Timer
        DB(uint16_t magic;)
 } Timer;
 
-/** Timer is active when Timer.magic contains this value (for debugging purposes). */
+/* Timer is active when Timer.magic contains this value (for debugging purposes). */
 #define TIMER_MAGIC_ACTIVE    0xABBA
 #define TIMER_MAGIC_INACTIVE  0xBAAB
 
 void timer_add(Timer *timer);
 Timer *timer_abort(Timer *timer);
 
-/** Set the timer so that it calls an user hook when it expires */
+/**
+ * Set the timer so that it calls an user hook when it expires
+ *
+ * Sometimes you may want to use the same callback for different events, so you must have
+ * different data to operate on. The user_data parameter is such data.
+ *
+ * \param timer Timer struct to set the callback to
+ * \param func  Function that will be called when the timer expires
+ * \param user_data Additional data you may want to pass to the callback
+ */
 INLINE void timer_setSoftint(Timer *timer, Hook func, iptr_t user_data)
 {
        event_initSoftint(&timer->expire, func, user_data);
@@ -262,6 +290,15 @@ INLINE void timer_setDelay(Timer *timer, ticks_t delay)
        timer->_delay = delay;
 }
 
+
+void synctimer_add(Timer *timer, List* q);
+
+/** \sa timer_abort */
+#define synctimer_abort(t) timer_abort(t)
+
+void synctimer_poll(List* q);
+
+
 #endif /* CONFIG_TIMER_EVENTS */
 
 #if defined(CONFIG_KERN_SIGNALS) && CONFIG_KERN_SIGNALS