watchdog: remove manager

Watchdog can handle callbacks - VirtualManager can attach to the tick. This should simplify the logic.

Watchdog can tick on its own using tickers.
VirtualWatchdog uses attach to get a callback when Watchdog ticks - to process own
linked list of virtual watchdogs.

Author: 0xc0170

drivers/VirtualWatchdog.cpp

@@ -31,7 +31,7 @@ VirtualWatchdog::VirtualWatchdog(uint32_t timeout, const char *const str): _name
     _max_timeout = timeout;
     // start watchdog
      Watchdog& watchdog = Watchdog::get_instance();
-     watchdog.start(&VirtualWatchdog::process, WatchdogManager::elapsed_ms);
+     watchdog.start(&VirtualWatchdog::process, Watchdog::elapsed_ms);
 }
 
 VirtualWatchdog::~VirtualWatchdog()
@@ -104,7 +104,7 @@ void VirtualWatchdog::process()
         if (cur_ptr->_current_count > cur_ptr->_max_timeout) {
             system_reset();
         } else {
-            cur_ptr->_current_count += WatchdogManager::elapsed_ms;
+            cur_ptr->_current_count += Watchdog::elapsed_ms;
         }
         cur_ptr = cur_ptr->_next;
     }

drivers/VirtualWatchdog.h

@@ -25,7 +25,6 @@
 #include "platform/mbed_critical.h"
 #include "platform/mbed_power_mgmt.h"
 #include "mbed_assert.h"
-#include "WatchdogManager.h"
 
 namespace mbed {
 

drivers/Watchdog.cpp

@@ -50,7 +50,7 @@ bool Watchdog::start(Callback<void()> func, uint32_t timeout)
     core_util_critical_section_exit();
     if (_running) {
         us_timestamp_t ticker_timeout = (MS_TO_US(((timeout <= 0) ? 1 : timeout)));
-        WatchdogManager::attach(callback(this, &Watchdog::kick), ticker_timeout);
+        _ticker->attach(callback(this, &Watchdog::kick), ticker_timeout);
     }
     return _running;
 }
@@ -66,7 +66,7 @@ bool Watchdog::stop()
         if (sts != WATCHDOG_STATUS_OK) {
             msts = false;
         } else {
-            WatchdogManager::detach();
+            _ticker->detach();
             _running = false;
             _callback = NULL;
         }
@@ -83,6 +83,7 @@ void Watchdog::kick()
     core_util_critical_section_enter();
     hal_watchdog_kick();
     core_util_critical_section_exit();
+
     if (_callback) {
         _callback();
     }

drivers/Watchdog.h

@@ -50,6 +50,7 @@ namespace mbed {
  */
 class Watchdog : private NonCopyable<Watchdog>  {
 public:
+    const uint32_t watchdog_timeout = MBED_CONF_TARGET_WATCHDOG_TIMEOUT / 2;
 
     /** As Watchdog might not stop ever, there is just one instance - we use single instance.
       * This ensures we keep Watchdog alive. To operate watchdog, use start/stop methods.
@@ -70,7 +71,7 @@ class Watchdog : private NonCopyable<Watchdog>  {
      *                 successfully. assert if one of the input parameters is out of range for the current platform.
      *                 false if watchdog timer was not started
      */
-    bool start(Callback<void()> func = NULL, uint32_t timeout =  WatchdogManager::elapsed_ms);
+    bool start(Callback<void()> func = NULL, uint32_t timeout =  watchdog_timeout);
 
     /** Stops the watchdog timer
      *
@@ -106,12 +107,25 @@ class Watchdog : private NonCopyable<Watchdog>  {
     bool is_running() const;
 
     void kick();
+
+
 private:
     Watchdog();
     ~Watchdog();
 
     bool _running;
     Callback<void()> _callback;
+
+#if DEVICE_LPTICKER
+    /** Create singleton instance of LowPowerTicker for watchdog periodic call back of kick.
+     */
+    SingletonPtr<LowPowerTicker> _ticker;
+#else
+    /** Create singleton instance of Ticker for watchdog periodic call back of kick.
+     */
+    SingletonPtr<Ticker> _ticker;
+#endif
+
 };
 
 } // namespace mbed