sys/event/timeout: remove alternative xtimer implementation

The old event_timeout API is no soley implemented on top of ztimer_usec.

sys/Makefile.dep

@@ -539,13 +539,8 @@ ifneq (,$(filter event_timeout_ztimer,$(USEMODULE)))
 endif
 
 ifneq (,$(filter event_timeout,$(USEMODULE)))
-  ifneq (,$(filter event_timeout_ztimer,$(USEMODULE)))
+  USEMODULE += event_timeout_ztimer
-    USEMODULE += ztimer_usec
+  USEMODULE += ztimer_usec
-  else
-    ifeq (,$(filter ztimer_usec,$(USEMODULE)))
-      USEMODULE += xtimer
-    endif
-  endif
 endif
 
 ifneq (,$(filter event_periodic,$(USEMODULE)))

sys/event/Kconfig

@@ -49,24 +49,7 @@ config MODULE_EVENT_TIMEOUT_ZTIMER
 
 config MODULE_EVENT_TIMEOUT
     bool "Legacy API, support for triggering events after timeout"
-
-if MODULE_EVENT_TIMEOUT
-
-choice EVENT_TIMEOUT_IMPLEMENTATION
-    bool "Event Timeout Implementation"
-    default EVENT_TIMEOUT_ON_XTIMER
-
-config EVENT_TIMEOUT_ON_ZTIMER
-    bool "Use ztimer as backend"
     select MODULE_EVENT_TIMEOUT_ZTIMER
     select ZTIMER_USEC
 
-config EVENT_TIMEOUT_ON_XTIMER
-    bool "Use xtimer as backend"
-    select MODULE_XTIMER if !ZTIMER_USEC
-
-endchoice # EVENT_TIMEOUT_IMPLEMENTATION
-
-endif # MODULE_EVENT_TIMEOUT
-
 endif # MODULE_EVENT

sys/event/Makefile

@@ -2,10 +2,4 @@ SRC := event.c
 
 SUBMODULES := 1
 
-ifneq (,$(filter event_timeout_ztimer,$(USEMODULE)))
-  ifneq (,$(filter ztimer_usec,$(USEMODULE)))
-    SUBMODULES_NO_SRC += timeout.c
-  endif
-endif
-
 include $(RIOTBASE)/Makefile.base

sys/event/timeout.c

@@ -1,42 +0,0 @@
-/*
- * Copyright (C) 2017 Inria
- *               2017 Freie Universität Berlin
- *               2017 Kaspar Schleiser <kaspar@schleiser.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.
- */
-
-#include "kernel_defines.h"
-#include "event/timeout.h"
-#if IS_USED(MODULE_ZTIMER_USEC)
-#include "ztimer/xtimer_compat.h"
-#else
-#include "xtimer.h"
-#endif
-
-static void _event_timeout_callback(void *arg)
-{
-    event_timeout_t *event_timeout = (event_timeout_t *)arg;
-
-    event_post(event_timeout->queue, event_timeout->event);
-}
-
-void event_timeout_init(event_timeout_t *event_timeout, event_queue_t *queue, event_t *event)
-{
-    event_timeout->timer.callback = _event_timeout_callback;
-    event_timeout->timer.arg = event_timeout;
-    event_timeout->queue = queue;
-    event_timeout->event = event;
-}
-
-void event_timeout_set(event_timeout_t *event_timeout, uint32_t timeout)
-{
-    xtimer_set(&event_timeout->timer, timeout);
-}
-
-void event_timeout_clear(event_timeout_t *event_timeout)
-{
-    xtimer_remove(&event_timeout->timer);
-}

sys/include/event/timeout.h

@@ -38,11 +38,7 @@
 #define EVENT_TIMEOUT_H
 
 #include "event.h"
-#if IS_USED(MODULE_EVENT_TIMEOUT_ZTIMER) || IS_USED(MODULE_ZTIMER_USEC)
 #include "ztimer.h"
-#else
-#include "xtimer.h"
-#endif
 
 #ifdef __cplusplus
 extern "C" {
@@ -52,19 +48,12 @@ extern "C" {
  * @brief   Timeout Event structure
  */
 typedef struct {
-#if IS_USED(MODULE_EVENT_TIMEOUT_ZTIMER)
     ztimer_clock_t *clock;  /**< ztimer clock to use */
-#endif
-#if IS_USED(MODULE_EVENT_TIMEOUT_ZTIMER) || IS_USED(MODULE_ZTIMER_USEC)
     ztimer_t timer;         /**< ztimer object used for timeout */
-#else
-    xtimer_t timer;         /**< ztimer object used for timeout */
-#endif
     event_queue_t *queue;   /**< event queue to post event to   */
     event_t *event;         /**< event to post after timeout    */
 } event_timeout_t;
 
-#if IS_USED(MODULE_EVENT_TIMEOUT_ZTIMER) || DOXYGEN
 /**
  * @brief   Initialize timeout event object
  *
@@ -75,7 +64,6 @@ typedef struct {
  */
 void event_timeout_ztimer_init(event_timeout_t *event_timeout, ztimer_clock_t *clock,
                                event_queue_t *queue, event_t *event);
-#endif
 
 #if IS_USED(MODULE_EVENT_TIMEOUT) || DOXYGEN
 /**