Update lp ticker wrapper

Create a dedicated header file for mbed_lp_ticker_wrapper along
with adding the function lp_ticker_get_timeout_pending to tell if
the a Timeout object is used by the lp ticker.

Author: c1728p9

hal/mbed_lp_ticker_api.c

@@ -14,11 +14,10 @@
  * limitations under the License.
  */
 #include "hal/lp_ticker_api.h"
+#include "hal/mbed_lp_ticker_wrapper.h"
 
 #if DEVICE_LPTICKER
 
-void lp_ticker_set_interrupt_wrapper(timestamp_t timestamp);
-
 static ticker_event_queue_t events = { 0 };
 
 static ticker_irq_handler_type irq_handler = ticker_irq_handler;

hal/mbed_lp_ticker_wrapper.cpp

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-#include "hal/lp_ticker_api.h"
+#include "hal/mbed_lp_ticker_wrapper.h"
 
 #if DEVICE_LPTICKER && (LPTICKER_DELAY_TICKS > 0)
 
@@ -104,22 +104,7 @@ static void set_interrupt_later()
     core_util_critical_section_exit();
 }
 
-/**
- * Wrapper around lp_ticker_set_interrupt to prevent blocking
- *
- * Problems this function is solving:
- * 1. Interrupt may not fire if set earlier than LPTICKER_DELAY_TICKS low power clock cycles
- * 2. Setting the interrupt back-to-back will block
- *
- * This wrapper function prevents lp_ticker_set_interrupt from being called
- * back-to-back and blocking while the first write is in progress. This function
- * avoids that problem by scheduling a timeout event if the lp ticker is in the
- * middle of a write operation.
- *
- * @param timestamp Time to call ticker irq
- * @note this is a utility function and it's not required part of HAL implementation
- */
-extern "C" void lp_ticker_set_interrupt_wrapper(timestamp_t timestamp)
+void lp_ticker_set_interrupt_wrapper(timestamp_t timestamp)
 {
     core_util_critical_section_enter();
 
@@ -153,4 +138,15 @@ extern "C" void lp_ticker_set_interrupt_wrapper(timestamp_t timestamp)
     core_util_critical_section_exit();
 }
 
+bool lp_ticker_get_timeout_pending()
+{
+    core_util_critical_section_enter();
+
+    bool pending = timeout_pending;
+
+    core_util_critical_section_exit();
+
+    return pending;
+}
+
 #endif

hal/mbed_lp_ticker_wrapper.h

@@ -0,0 +1,67 @@
+
+/** \addtogroup hal */
+/** @{*/
+/* mbed Microcontroller Library
+ * Copyright (c) 2018 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef MBED_LP_TICKER_WRAPPER_H
+#define MBED_LP_TICKER_WRAPPER_H
+
+#include "device.h"
+
+#if DEVICE_LPTICKER && (LPTICKER_DELAY_TICKS > 0)
+
+#include "hal/ticker_api.h"
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Wrapper around lp_ticker_set_interrupt to prevent blocking
+ *
+ * Problems this function is solving:
+ * 1. Interrupt may not fire if set earlier than LPTICKER_DELAY_TICKS low power clock cycles
+ * 2. Setting the interrupt back-to-back will block
+ *
+ * This wrapper function prevents lp_ticker_set_interrupt from being called
+ * back-to-back and blocking while the first write is in progress. This function
+ * avoids that problem by scheduling a timeout event if the lp ticker is in the
+ * middle of a write operation.
+ *
+ * @param timestamp Time to call ticker irq
+ * @note this is a utility function and it's not required part of HAL implementation
+ */
+void lp_ticker_set_interrupt_wrapper(timestamp_t timestamp);
+
+/**
+ * Check if the Timer object used by the wrapper is active
+ *
+ * @return true if the Timer object is scheduled, false otherwise
+ */
+bool lp_ticker_get_timeout_pending();
+
+/**@}*/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+#endif
+
+/** @}*/