Merge pull request #3982 from mjrgh/patch-3

Ticker - kl25z bugfix for handling events in the past

Author: sg-

hal/mbed_ticker_api.c

@@ -74,15 +74,17 @@ void ticker_insert_event(const ticker_data_t *const data, ticker_event_t *obj, t
         prev = p;
         p = p->next;
     }
+    
+    /* if we're at the end p will be NULL, which is correct */
+    obj->next = p;
+
     /* if prev is NULL we're at the head */
     if (prev == NULL) {
         data->queue->head = obj;
         data->interface->set_interrupt(timestamp);
     } else {
         prev->next = obj;
     }
-    /* if we're at the end p will be NULL, which is correct */
-    obj->next = p;
 
     core_util_critical_section_exit();
 }

targets/TARGET_Freescale/TARGET_KLXX/us_ticker.c

@@ -187,11 +187,11 @@ static void lptmr_isr(void) {
 void us_ticker_set_interrupt(timestamp_t timestamp) {
     int delta = (int)((uint32_t)timestamp - us_ticker_read());
     if (delta <= 0) {
-        // This event was in the past:
-        us_ticker_irq_handler();
-        return;
-    }
-    
+        // This event was in the past.  Force it into the very near
+	// future instead.
+	delta = 1;
+    } 
+	
     us_ticker_int_counter   = (uint32_t)(delta >> 16);
     us_ticker_int_remainder = (uint16_t)(0xFFFF & delta);
     if (us_ticker_int_counter > 0) {