periph_driver: introduce a RTT interface

drivers/include/periph/rtt.h

@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2014 Thomas Eichinger <thomas.eichinger@fu-berlin.de>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser General
+ * Public License v2.1. See the file LICENSE in the top level directory for more
+ * details.
+ */
+/**
+ * @ingroup     driver_periph
+ * @{
+ *
+ * @file        rtt.h
+ * @brief       Low-level RTT (Real Time Timer) peripheral driver interface
+ *              definitions
+ *
+ * @author      Thomas Eichinger <thomas.eichinger@fu-berlin.de>
+ */
+
+#ifndef __RTT_H
+#define __RTT_H
+
+#include "periph_conf.h"
+
+/* guard file in case no RTC device was specified */
+#if RTT_NUMOF
+
+/**
+ * @brief Signature for alarm Callback
+ *
+ * @param[in] arg           optional argument to put the callback in the right context
+ */
+typedef void(*rtt_alarm_cb_t)(void *arg);
+
+/**
+ * @brief Initialize RTT module
+ */
+void rtt_init(void);
+
+/**
+ * @brief Get the current RTT counter.
+ *
+ * @return Current value of the RTT counter.
+ */
+uint32_t rtt_get_counter(void);
+
+/**
+ * @brief Set the RTT counter to a specified value.
+ *
+ * @param[in] counter       The value to set the RTT to.
+ */
+void rtt_set_counter(uint32_t counter);
+
+/**
+ * @brief Set an alarm for RTT to the specified value.
+ *
+ * @param[in] alarm         The value to trigger an alarm when hit.
+ * @param[in] cb            Callback executed when alarm is hit.
+ * @param[in] arg           Argument passed to callback when alarm is hit.
+ */
+void rtt_set_alarm(uint32_t alarm, rtt_alarm_cb_t cb, void *arg);
+
+/**
+ * @brief Get the value of a set alarm.
+ *
+ * If no alarm is set the return value is arbitrary.
+ *
+ * @return                  value the alarm is set to
+ */
+uint32_t rtt_get_alarm(void);
+
+/**
+ * @brief Clear any set alarm, do nothing if nothing set
+ */
+void rtt_clear_alarm(void);
+
+/**
+ * @brief Turns the RTC hardware module on
+ */
+void rtt_poweron(void);
+
+/**
+ * @brief Turns the RTC hardware module off
+ */
+void rtt_poweroff(void);
+
+#endif /* RTT_NUMOF */
+#endif /* __RTT_H */
+/** @} */