Gan likun
00
Diff: hal/ticker_api.h
- Revision:
- 0:13413ea9a877
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hal/ticker_api.h Sun Jun 12 14:02:44 2022 +0000
@@ -0,0 +1,182 @@
+
+/** \addtogroup hal */
+/** @{*/
+/* mbed Microcontroller Library
+ * Copyright (c) 2015 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_TICKER_API_H
+#define MBED_TICKER_API_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "device.h"
+
+/**
+ * Maximum delta (in us) between too interrupts.
+ */
+#define MBED_TICKER_INTERRUPT_TIMESTAMP_MAX_DELTA 0x70000000ULL
+
+/**
+ * Legacy format representing a timestamp in us.
+ * Given it is modeled as a 32 bit integer, this type can represent timestamp
+ * up to 4294 seconds (71 minutes).
+ * Prefer using us_timestamp_t which store timestamp as 64 bits integer.
+ */
+typedef uint32_t timestamp_t;
+
+/**
+ * A us timestamp stored in a 64 bit integer.
+ * Can store timestamp up to 584810 years.
+ */
+typedef uint64_t us_timestamp_t;
+
+/** Ticker's event structure
+ */
+typedef struct ticker_event_s {
+ us_timestamp_t timestamp; /**< Event's timestamp */
+ uint32_t id; /**< TimerEvent object */
+ struct ticker_event_s *next; /**< Next event in the queue */
+} ticker_event_t;
+
+typedef void (*ticker_event_handler)(uint32_t id);
+
+/** Ticker's interface structure - required API for a ticker
+ */
+typedef struct {
+ void (*init)(void); /**< Init function */
+ uint32_t (*read)(void); /**< Read function */
+ void (*disable_interrupt)(void); /**< Disable interrupt function */
+ void (*clear_interrupt)(void); /**< Clear interrupt function */
+ void (*set_interrupt)(timestamp_t timestamp); /**< Set interrupt function */
+ void (*fire_interrupt)(void); /**< Fire interrupt right-away */
+} ticker_interface_t;
+
+/** Ticker's event queue structure
+ */
+typedef struct {
+ ticker_event_handler event_handler; /**< Event handler */
+ ticker_event_t *head; /**< A pointer to head */
+ us_timestamp_t present_time; /**< Store the timestamp used for present time */
+ bool initialized; /**< Indicate if the instance is initialized */
+} ticker_event_queue_t;
+
+/** Ticker's data structure
+ */
+typedef struct {
+ const ticker_interface_t *interface; /**< Ticker's interface */
+ ticker_event_queue_t *queue; /**< Ticker's event queue */
+} ticker_data_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \defgroup hal_ticker Ticker HAL functions
+ * @{
+ */
+
+/** Initialize a ticker and set the event handler
+ *
+ * @param ticker The ticker object.
+ * @param handler A handler to be set
+ */
+void ticker_set_handler(const ticker_data_t *const ticker, ticker_event_handler handler);
+
+/** IRQ handler that goes through the events to trigger overdue events.
+ *
+ * @param ticker The ticker object.
+ */
+void ticker_irq_handler(const ticker_data_t *const ticker);
+
+/** Remove an event from the queue
+ *
+ * @param ticker The ticker object.
+ * @param obj The event object to be removed from the queue
+ */
+void ticker_remove_event(const ticker_data_t *const ticker, ticker_event_t *obj);
+
+/** Insert an event to the queue
+ *
+ * The event will be executed in timestamp - ticker_read().
+ *
+ * @warning This function does not consider timestamp in the past. If an event
+ * is inserted with a timestamp less than the current timestamp then the event
+ * will be executed in timestamp - ticker_read() us.
+ * The internal counter wrap very quickly it is hard to decide weither an
+ * event is in the past or in 1 hour.
+ *
+ * @note prefer the use of ticker_insert_event_us which allows registration of
+ * absolute timestamp.
+ *
+ * @param ticker The ticker object.
+ * @param obj The event object to be inserted to the queue
+ * @param timestamp The event's timestamp
+ * @param id The event object
+ */
+void ticker_insert_event(const ticker_data_t *const ticker, ticker_event_t *obj, timestamp_t timestamp, uint32_t id);
+
+/** Insert an event to the queue
+ *
+ * The event will be executed in timestamp - ticker_read_us() us.
+ *
+ * @warning If an event is inserted with a timestamp less than the current
+ * timestamp then the event will **not** be inserted.
+ *
+ * @param ticker The ticker object.
+ * @param obj The event object to be inserted to the queue
+ * @param timestamp The event's timestamp
+ * @param id The event object
+ */
+void ticker_insert_event_us(const ticker_data_t *const ticker, ticker_event_t *obj, us_timestamp_t timestamp, uint32_t id);
+
+/** Read the current (relative) ticker's timestamp
+ *
+ * @warning Return a relative timestamp because the counter wrap every 4294
+ * seconds.
+ *
+ * @param ticker The ticker object.
+ * @return The current timestamp
+ */
+timestamp_t ticker_read(const ticker_data_t *const ticker);
+
+/** Read the current (absolute) ticker's timestamp
+ *
+ * @warning Return an absolute timestamp counting from the initialization of the
+ * ticker.
+ *
+ * @param ticker The ticker object.
+ * @return The current timestamp
+ */
+us_timestamp_t ticker_read_us(const ticker_data_t *const ticker);
+
+/** Read the next event's timestamp
+ *
+ * @param ticker The ticker object.
+ * @param timestamp The timestamp object.
+ * @return 1 if timestamp is pending event, 0 if there's no event pending
+ */
+int ticker_get_next_timestamp(const ticker_data_t *const ticker, timestamp_t *timestamp);
+
+/**@}*/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+/** @}*/
+