Watchdog: refactor timeout handling

Enable kicking directly by kick() and handle timeout by using private handler.

Author: 0xc0170

drivers/Watchdog.cpp

@@ -54,7 +54,7 @@ bool Watchdog::start(Callback<void(uint32_t)> func, uint32_t timeout)
         if (_ticker_timeout == 0) {
             _ticker_timeout = 1;
         }
-        _ticker->attach_us(callback(this, &Watchdog::kick), _ticker_timeout);
+        _ticker->attach_us(callback(this, &Watchdog::timeout_handler), _ticker_timeout);
     }
     return _running;
 }
@@ -87,13 +87,16 @@ void Watchdog::kick()
     core_util_critical_section_enter();
     hal_watchdog_kick();
     core_util_critical_section_exit();
+}
 
+void Watchdog::timeout_handler()
+{
+    kick();
     if (_callback) {
         _callback(_ticker_timeout);
     }
 }
 
-
 bool Watchdog::is_running() const
 {
     return _running;

drivers/Watchdog.h

@@ -121,6 +121,10 @@ class Watchdog : private NonCopyable<Watchdog>  {
     Watchdog();
     ~Watchdog();
 
+    /** Ticker invokes this handler when it timeouts - kicking watchdog periodically 
+     */
+    void timeout_handler();
+
     bool _running;
     Callback<void(uint32_t)> _callback;
     us_timestamp_t _ticker_timeout;