From 7eeea869ac36a65502e785a821bb334ac8a84d98 Mon Sep 17 00:00:00 2001
From: Lucian Copeland <hierophect@gmail.com>
Date: Tue, 13 Apr 2021 18:31:57 -0400
Subject: [PATCH 1/3] Fix light sleep global alarms, API revisions

---
 main.c                                        |  2 +-
 ports/esp32s2/common-hal/alarm/__init__.c     | 67 ++++++++++++-------
 ports/esp32s2/common-hal/alarm/pin/PinAlarm.c | 13 +++-
 ports/esp32s2/common-hal/alarm/pin/PinAlarm.h |  8 ++-
 .../esp32s2/common-hal/alarm/time/TimeAlarm.c |  9 ++-
 .../esp32s2/common-hal/alarm/time/TimeAlarm.h | 10 +--
 .../common-hal/alarm/touch/TouchAlarm.c       |  8 ++-
 .../common-hal/alarm/touch/TouchAlarm.h       | 10 +--
 shared-bindings/alarm/__init__.c              |  4 +-
 shared-bindings/alarm/__init__.h              | 21 ++++--
 10 files changed, 94 insertions(+), 58 deletions(-)

diff --git a/main.c b/main.c
index 1e828a1aa7..12801a535e 100755
--- a/main.c
+++ b/main.c
@@ -161,7 +161,7 @@ STATIC void start_mp(supervisor_allocation* heap) {
 
     #if CIRCUITPY_ALARM
     // Record which alarm woke us up, if any. An object may be created so the heap must be functional.
-    shared_alarm_save_wake_alarm();
+    shared_alarm_save_wake_alarm(common_hal_alarm_create_wake_alarm());
     // Reset alarm module only after we retrieved the wakeup alarm.
     alarm_reset();
     #endif
diff --git a/ports/esp32s2/common-hal/alarm/__init__.c b/ports/esp32s2/common-hal/alarm/__init__.c
index 63a19ab948..f1d4bb36f5 100644
--- a/ports/esp32s2/common-hal/alarm/__init__.c
+++ b/ports/esp32s2/common-hal/alarm/__init__.c
@@ -63,15 +63,18 @@ void alarm_reset(void) {
 }
 
 STATIC esp_sleep_wakeup_cause_t _get_wakeup_cause(void) {
-    if (alarm_pin_pinalarm_woke_us_up()) {
+    // First check if the modules remember what last woke up
+    if (alarm_pin_pinalarm_woke_this_cycle()) {
         return ESP_SLEEP_WAKEUP_GPIO;
     }
-    if (alarm_time_timealarm_woke_us_up()) {
+    if (alarm_time_timealarm_woke_this_cycle()) {
         return ESP_SLEEP_WAKEUP_TIMER;
     }
-    if (alarm_touch_touchalarm_woke_us_up()) {
+    if (alarm_touch_touchalarm_woke_this_cycle()) {
         return ESP_SLEEP_WAKEUP_TOUCHPAD;
     }
+    // If waking from true deep sleep, modules will have lost their state,
+    // so check the deep wakeup cause manually
     return esp_sleep_get_wakeup_cause();
 }
 
@@ -79,21 +82,23 @@ bool common_hal_alarm_woken_from_sleep(void) {
     return _get_wakeup_cause() != ESP_SLEEP_WAKEUP_UNDEFINED;
 }
 
-STATIC mp_obj_t _get_wake_alarm(size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t common_hal_alarm_create_wake_alarm(void) {
+    // If woken from deep sleep, create a copy alarm similar to what would have
+    // been passed in originally. Otherwise, just return none
     esp_sleep_wakeup_cause_t cause = _get_wakeup_cause();
     switch (cause) {
         case ESP_SLEEP_WAKEUP_TIMER: {
-            return alarm_time_timealarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_time_timealarm_create_wakeup_alarm();
         }
 
         case ESP_SLEEP_WAKEUP_GPIO:
         case ESP_SLEEP_WAKEUP_EXT0:
         case ESP_SLEEP_WAKEUP_EXT1: {
-            return alarm_pin_pinalarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_pin_pinalarm_create_wakeup_alarm();
         }
 
         case ESP_SLEEP_WAKEUP_TOUCHPAD: {
-            return alarm_touch_touchalarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_touch_touchalarm_create_wakeup_alarm();
         }
 
         case ESP_SLEEP_WAKEUP_UNDEFINED:
@@ -104,10 +109,6 @@ STATIC mp_obj_t _get_wake_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     return mp_const_none;
 }
 
-mp_obj_t common_hal_alarm_get_wake_alarm(void) {
-    return _get_wake_alarm(0, NULL);
-}
-
 // Set up light sleep or deep sleep alarms.
 STATIC void _setup_sleep_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms) {
     alarm_pin_pinalarm_set_alarms(deep_sleep, n_alarms, alarms);
@@ -115,30 +116,44 @@ STATIC void _setup_sleep_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t
     alarm_touch_touchalarm_set_alarm(deep_sleep, n_alarms, alarms);
 }
 
-STATIC void _idle_until_alarm(void) {
-    // Poll for alarms.
-    while (!mp_hal_is_interrupted()) {
-        RUN_BACKGROUND_TASKS;
-        // Allow ctrl-C interrupt.
-        if (common_hal_alarm_woken_from_sleep()) {
-            shared_alarm_save_wake_alarm();
-            return;
-        }
-        port_idle_until_interrupt();
-    }
-}
-
 mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const mp_obj_t *alarms) {
     _setup_sleep_alarms(false, n_alarms, alarms);
 
+    mp_obj_t wake_alarm = mp_const_none;
+
     // We cannot esp_light_sleep_start() here because it shuts down all non-RTC peripherals.
-    _idle_until_alarm();
+    while (!mp_hal_is_interrupted()) {
+        RUN_BACKGROUND_TASKS;
+        // Detect if interrupt was alarm or ctrl-C interrupt.
+        if (common_hal_alarm_woken_from_sleep()) {
+            esp_sleep_wakeup_cause_t cause = _get_wakeup_cause();
+            switch (cause) {
+                case ESP_SLEEP_WAKEUP_TIMER: {
+                    wake_alarm = alarm_time_timealarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                case ESP_SLEEP_WAKEUP_GPIO: {
+                    wake_alarm = alarm_pin_pinalarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                case ESP_SLEEP_WAKEUP_TOUCHPAD: {
+                    wake_alarm = alarm_touch_touchalarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                default:
+                    // Should not reach this, if all light sleep types are covered correctly
+                    break;
+            }
+            shared_alarm_save_wake_alarm(wake_alarm);
+            break;
+        }
+        port_idle_until_interrupt();
+    }
 
     if (mp_hal_is_interrupted()) {
         return mp_const_none; // Shouldn't be given to python code because exception handling should kick in.
     }
 
-    mp_obj_t wake_alarm = _get_wake_alarm(n_alarms, alarms);
     alarm_reset();
     return wake_alarm;
 }
diff --git a/ports/esp32s2/common-hal/alarm/pin/PinAlarm.c b/ports/esp32s2/common-hal/alarm/pin/PinAlarm.c
index 9ccb5700cb..34b4a2f918 100644
--- a/ports/esp32s2/common-hal/alarm/pin/PinAlarm.c
+++ b/ports/esp32s2/common-hal/alarm/pin/PinAlarm.c
@@ -96,12 +96,11 @@ void gpio_interrupt(void *arg) {
     }
 }
 
-bool alarm_pin_pinalarm_woke_us_up(void) {
+bool alarm_pin_pinalarm_woke_this_cycle(void) {
     return pin_31_0_status != 0 || pin_63_32_status != 0;
 }
 
-mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms) {
-    // First, check to see if we match any given alarms.
+mp_obj_t alarm_pin_pinalarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     uint64_t pin_status = ((uint64_t)pin_63_32_status) << 32 | pin_31_0_status;
     for (size_t i = 0; i < n_alarms; i++) {
         if (!MP_OBJ_IS_TYPE(alarms[i], &alarm_pin_pinalarm_type)) {
@@ -112,8 +111,16 @@ mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *al
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
+
+mp_obj_t alarm_pin_pinalarm_create_wakeup_alarm(void) {
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
+
+    // Pin status will persist into a fake deep sleep
+    uint64_t pin_status = ((uint64_t)pin_63_32_status) << 32 | pin_31_0_status;
     size_t pin_number = 64;
+
     if (cause == ESP_SLEEP_WAKEUP_EXT0) {
         pin_number = REG_GET_FIELD(RTC_IO_EXT_WAKEUP0_REG, RTC_IO_EXT_WAKEUP0_SEL);
     } else {
diff --git a/ports/esp32s2/common-hal/alarm/pin/PinAlarm.h b/ports/esp32s2/common-hal/alarm/pin/PinAlarm.h
index 93672c1f2d..b2326ed0d3 100644
--- a/ports/esp32s2/common-hal/alarm/pin/PinAlarm.h
+++ b/ports/esp32s2/common-hal/alarm/pin/PinAlarm.h
@@ -34,8 +34,10 @@ typedef struct {
     bool pull;
 } alarm_pin_pinalarm_obj_t;
 
+mp_obj_t alarm_pin_pinalarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_pin_pinalarm_create_wakeup_alarm(void);
+
+void alarm_pin_pinalarm_prepare_for_deep_sleep(void);
 void alarm_pin_pinalarm_reset(void);
 void alarm_pin_pinalarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
-void alarm_pin_pinalarm_prepare_for_deep_sleep(void);
-mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms);
-bool alarm_pin_pinalarm_woke_us_up(void);
+bool alarm_pin_pinalarm_woke_this_cycle(void);
diff --git a/ports/esp32s2/common-hal/alarm/time/TimeAlarm.c b/ports/esp32s2/common-hal/alarm/time/TimeAlarm.c
index 93e4f18091..24cc254032 100644
--- a/ports/esp32s2/common-hal/alarm/time/TimeAlarm.c
+++ b/ports/esp32s2/common-hal/alarm/time/TimeAlarm.c
@@ -42,13 +42,16 @@ mp_float_t common_hal_alarm_time_timealarm_get_monotonic_time(alarm_time_timeala
     return self->monotonic_time;
 }
 
-mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms) {
-    // First, check to see if we match
+mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     for (size_t i = 0; i < n_alarms; i++) {
         if (MP_OBJ_IS_TYPE(alarms[i], &alarm_time_timealarm_type)) {
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
+
+mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void) {
     alarm_time_timealarm_obj_t *timer = m_new_obj(alarm_time_timealarm_obj_t);
     timer->base.type = &alarm_time_timealarm_type;
     // TODO: Set monotonic_time based on the RTC state.
@@ -66,7 +69,7 @@ void timer_callback(void *arg) {
     xTaskNotifyGive(circuitpython_task);
 }
 
-bool alarm_time_timealarm_woke_us_up(void) {
+bool alarm_time_timealarm_woke_this_cycle(void) {
     return woke_up;
 }
 
diff --git a/ports/esp32s2/common-hal/alarm/time/TimeAlarm.h b/ports/esp32s2/common-hal/alarm/time/TimeAlarm.h
index dfd75524fd..36986e06b2 100644
--- a/ports/esp32s2/common-hal/alarm/time/TimeAlarm.h
+++ b/ports/esp32s2/common-hal/alarm/time/TimeAlarm.h
@@ -32,9 +32,9 @@ typedef struct {
     mp_float_t monotonic_time;      // values compatible with time.monotonic_time()
 } alarm_time_timealarm_obj_t;
 
-// Find the alarm object that caused us to wake up or create an equivalent one.
-mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms);
-// Check for the wake up alarm from pretend deep sleep.
-bool alarm_time_timealarm_woke_us_up(void);
-void alarm_time_timealarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void);
+
 void alarm_time_timealarm_reset(void);
+void alarm_time_timealarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
+bool alarm_time_timealarm_woke_this_cycle(void);
diff --git a/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.c b/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.c
index 8c139afaf3..12c835b73c 100644
--- a/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.c
+++ b/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.c
@@ -42,14 +42,16 @@ void common_hal_alarm_touch_touchalarm_construct(alarm_touch_touchalarm_obj_t *s
     self->pin = pin;
 }
 
-mp_obj_t alarm_touch_touchalarm_get_wakeup_alarm(const size_t n_alarms, const mp_obj_t *alarms) {
-    // First, check to see if we match any given alarms.
+mp_obj_t alarm_touch_touchalarm_find_triggered_alarm(const size_t n_alarms, const mp_obj_t *alarms) {
     for (size_t i = 0; i < n_alarms; i++) {
         if (MP_OBJ_IS_TYPE(alarms[i], &alarm_touch_touchalarm_type)) {
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
 
+mp_obj_t alarm_touch_touchalarm_create_wakeup_alarm(void) {
     // Create TouchAlarm object.
     alarm_touch_touchalarm_obj_t *alarm = m_new_obj(alarm_touch_touchalarm_obj_t);
     alarm->base.type = &alarm_touch_touchalarm_type;
@@ -168,7 +170,7 @@ void alarm_touch_touchalarm_prepare_for_deep_sleep(void) {
     esp_sleep_pd_config(ESP_PD_DOMAIN_RTC_PERIPH, ESP_PD_OPTION_ON);
 }
 
-bool alarm_touch_touchalarm_woke_us_up(void) {
+bool alarm_touch_touchalarm_woke_this_cycle(void) {
     return woke_up;
 }
 
diff --git a/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.h b/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.h
index 755a3977ad..df2521c12a 100644
--- a/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.h
+++ b/ports/esp32s2/common-hal/alarm/touch/TouchAlarm.h
@@ -35,12 +35,12 @@ typedef struct {
     const mcu_pin_obj_t *pin;
 } alarm_touch_touchalarm_obj_t;
 
-// Find the alarm object that caused us to wake up or create an equivalent one.
-mp_obj_t alarm_touch_touchalarm_get_wakeup_alarm(const size_t n_alarms, const mp_obj_t *alarms);
-// Check for the wake up alarm from pretend deep sleep.
-void alarm_touch_touchalarm_set_alarm(const bool deep_sleep, const size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_touch_touchalarm_find_triggered_alarm(const size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_touch_touchalarm_create_wakeup_alarm(void);
+
 void alarm_touch_touchalarm_prepare_for_deep_sleep(void);
-bool alarm_touch_touchalarm_woke_us_up(void);
 void alarm_touch_touchalarm_reset(void);
+void alarm_touch_touchalarm_set_alarm(const bool deep_sleep, const size_t n_alarms, const mp_obj_t *alarms);
+bool alarm_touch_touchalarm_woke_this_cycle(void);
 
 #endif  // MICROPY_INCLUDED_COMMON_HAL_ALARM_TOUCH_TOUCHALARM_H
diff --git a/shared-bindings/alarm/__init__.c b/shared-bindings/alarm/__init__.c
index 11b96ff240..58b67bc8d6 100644
--- a/shared-bindings/alarm/__init__.c
+++ b/shared-bindings/alarm/__init__.c
@@ -228,13 +228,13 @@ mp_obj_t shared_alarm_get_wake_alarm(void) {
 }
 
 // Initialize .wake_alarm value.
-void shared_alarm_save_wake_alarm(void) {
+void shared_alarm_save_wake_alarm(mp_obj_t alarm) {
     // Equivalent of:
     // alarm.wake_alarm = alarm
     mp_map_elem_t *elem =
         mp_map_lookup(&alarm_module_globals.map, MP_ROM_QSTR(MP_QSTR_wake_alarm), MP_MAP_LOOKUP);
     if (elem) {
-        elem->value = common_hal_alarm_get_wake_alarm();
+        elem->value = alarm;
     }
 }
 
diff --git a/shared-bindings/alarm/__init__.h b/shared-bindings/alarm/__init__.h
index 9c85b2e212..b1fc3ed05f 100644
--- a/shared-bindings/alarm/__init__.h
+++ b/shared-bindings/alarm/__init__.h
@@ -31,6 +31,9 @@
 
 #include "common-hal/alarm/__init__.h"
 
+// Light sleep fully self-contained and does not exit user code. It will return
+// the same alarm object that was orignally passed in, unlike deep sleep, which
+// must create an identical copy due to the VM reset
 extern mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const mp_obj_t *alarms);
 
 // Deep sleep is a two step process. Alarms are set when the VM is valid but
@@ -38,22 +41,26 @@ extern mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const
 // not actually happen if the user is connected to the device. In this case, the
 // supervisor will idle using `port_wait_for_interrupt`. After each call, it will
 // call alarm_woken_from_sleep to see if we've been woken by an alarm and if so,
-// it will exit idle as if deep sleep was exited.
+// it will exit idle as if deep sleep was exited
 extern void common_hal_alarm_set_deep_sleep_alarms(size_t n_alarms, const mp_obj_t *alarms);
-
 extern NORETURN void common_hal_alarm_enter_deep_sleep(void);
+
+// May be used to re-initialize peripherals like GPIO, if the VM reset returned
+// them to a default state
 extern void common_hal_alarm_pretending_deep_sleep(void);
 
 // Fetches value from module dict.
 extern mp_obj_t shared_alarm_get_wake_alarm(void);
 
-extern void common_hal_alarm_gc_collect(void);
-extern mp_obj_t common_hal_alarm_get_wake_alarm(void);
+// Creates a new alarm object after exiting deep sleep (real or fake)
+extern mp_obj_t common_hal_alarm_create_wake_alarm(void);
 
-// Used by wake-up code.
-void shared_alarm_save_wake_alarm(void);
+// Saves alarm to global array
+void shared_alarm_save_wake_alarm(mp_obj_t alarm);
 
-// True if an alarm is alerting. This is most useful for pretend deep sleep.
+// True if an alarm is alerting. Used in light sleep/fake deep sleep
 extern bool common_hal_alarm_woken_from_sleep(void);
 
+extern void common_hal_alarm_gc_collect(void);
+
 #endif  // MICROPY_INCLUDED_SHARED_BINDINGS_ALARM___INIT___H

From 715f7ee49022f39e7d988e4eeb4a1cb68a5525a8 Mon Sep 17 00:00:00 2001
From: Lucian Copeland <hierophect@gmail.com>
Date: Fri, 14 May 2021 14:34:35 -0400
Subject: [PATCH 2/3] Add STM32 and NRF52 compatibility

---
 ports/nrf/common-hal/alarm/__init__.c         | 44 ++++++++----
 ports/nrf/common-hal/alarm/pin/PinAlarm.c     |  8 ++-
 ports/nrf/common-hal/alarm/pin/PinAlarm.h     |  6 +-
 ports/nrf/common-hal/alarm/time/TimeAlarm.c   |  9 ++-
 ports/nrf/common-hal/alarm/time/TimeAlarm.h   |  7 +-
 ports/nrf/common-hal/alarm/touch/TouchAlarm.c |  8 ++-
 ports/nrf/common-hal/alarm/touch/TouchAlarm.h |  5 +-
 ports/stm/common-hal/alarm/__init__.c         | 71 +++++++++----------
 ports/stm/common-hal/alarm/pin/PinAlarm.c     |  8 ++-
 ports/stm/common-hal/alarm/pin/PinAlarm.h     |  6 +-
 ports/stm/common-hal/alarm/time/TimeAlarm.c   |  8 ++-
 ports/stm/common-hal/alarm/time/TimeAlarm.h   |  7 +-
 12 files changed, 110 insertions(+), 77 deletions(-)

diff --git a/ports/nrf/common-hal/alarm/__init__.c b/ports/nrf/common-hal/alarm/__init__.c
index 4a0fdeb8a0..a601e8768e 100644
--- a/ports/nrf/common-hal/alarm/__init__.c
+++ b/ports/nrf/common-hal/alarm/__init__.c
@@ -69,15 +69,18 @@ void alarm_reset(void) {
 
 extern uint32_t reset_reason_saved;
 STATIC nrf_sleep_source_t _get_wakeup_cause(void) {
-    if (alarm_pin_pinalarm_woke_us_up()) {
+    // First check if the modules remember what last woke up
+    if (alarm_pin_pinalarm_woke_this_cycle()) {
         return NRF_SLEEP_WAKEUP_GPIO;
     }
-    if (alarm_time_timealarm_woke_us_up()) {
+    if (alarm_time_timealarm_woke_this_cycle()) {
         return NRF_SLEEP_WAKEUP_TIMER;
     }
-    if (alarm_touch_touchalarm_woke_us_up()) {
+    if (alarm_touch_touchalarm_woke_this_cycle()) {
         return NRF_SLEEP_WAKEUP_TOUCHPAD;
     }
+    // If waking from true deep sleep, modules will have lost their state,
+    // so check the deep wakeup cause manually
     if (reset_reason_saved & NRF_POWER_RESETREAS_RESETPIN_MASK) {
         return NRF_SLEEP_WAKEUP_RESETPIN;
     } else if (reset_reason_saved & NRF_POWER_RESETREAS_OFF_MASK) {
@@ -116,17 +119,19 @@ bool common_hal_alarm_woken_from_sleep(void) {
            || cause == NRF_SLEEP_WAKEUP_TOUCHPAD;
 }
 
-STATIC mp_obj_t _get_wake_alarm(size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t common_hal_alarm_create_wake_alarm(void) {
+    // If woken from deep sleep, create a copy alarm similar to what would have
+    // been passed in originally. Otherwise, just return none
     nrf_sleep_source_t cause = _get_wakeup_cause();
     switch (cause) {
         case NRF_SLEEP_WAKEUP_TIMER: {
-            return alarm_time_timealarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_time_timealarm_create_wakeup_alarm();
         }
         case NRF_SLEEP_WAKEUP_TOUCHPAD: {
-            return alarm_touch_touchalarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_touch_touchalarm_create_wakeup_alarm();
         }
         case NRF_SLEEP_WAKEUP_GPIO: {
-            return alarm_pin_pinalarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_pin_pinalarm_create_wakeup_alarm();
         }
         default:
             break;
@@ -134,11 +139,6 @@ STATIC mp_obj_t _get_wake_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     return mp_const_none;
 }
 
-mp_obj_t common_hal_alarm_get_wake_alarm(void) {
-    mp_obj_t obj = _get_wake_alarm(0, NULL);
-    return obj;
-}
-
 // Set up light sleep or deep sleep alarms.
 STATIC void _setup_sleep_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms) {
     alarm_pin_pinalarm_set_alarms(deep_sleep, n_alarms, alarms);
@@ -257,7 +257,7 @@ void system_on_idle_until_alarm(int64_t timediff_ms, uint32_t prescaler) {
 }
 
 mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const mp_obj_t *alarms) {
-    mp_obj_t wake_alarm;
+    mp_obj_t wake_alarm = mp_const_none;
     alarm_time_timealarm_clear_wakeup_time();
     _setup_sleep_alarms(false, n_alarms, alarms);
 
@@ -271,7 +271,23 @@ mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const mp_obj
     if (mp_hal_is_interrupted()) {
         wake_alarm = mp_const_none;
     } else {
-        wake_alarm = _get_wake_alarm(n_alarms, alarms);
+        if (common_hal_alarm_woken_from_sleep()) {
+            nrf_sleep_source_t cause = _get_wakeup_cause();
+            switch (cause) {
+                case NRF_SLEEP_WAKEUP_TIMER: {
+                    wake_alarm = alarm_time_timealarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                case NRF_SLEEP_WAKEUP_GPIO: {
+                    wake_alarm = alarm_pin_pinalarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                default:
+                    // Should not reach this, if all light sleep types are covered correctly
+                    break;
+            }
+            shared_alarm_save_wake_alarm(wake_alarm);
+        }
     }
     alarm_reset();
     return wake_alarm;
diff --git a/ports/nrf/common-hal/alarm/pin/PinAlarm.c b/ports/nrf/common-hal/alarm/pin/PinAlarm.c
index be4df66172..b09e217c22 100644
--- a/ports/nrf/common-hal/alarm/pin/PinAlarm.c
+++ b/ports/nrf/common-hal/alarm/pin/PinAlarm.c
@@ -85,12 +85,12 @@ static void pinalarm_gpiote_handler(nrfx_gpiote_pin_t pin, nrf_gpiote_polarity_t
     sleepmem_wakeup_pin = pin & 0xFF;
 }
 
-bool alarm_pin_pinalarm_woke_us_up(void) {
+bool alarm_pin_pinalarm_woke_this_cycle(void) {
     return sleepmem_wakeup_event == SLEEPMEM_WAKEUP_BY_PIN &&
            sleepmem_wakeup_pin != WAKEUP_PIN_UNDEF;
 }
 
-mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t alarm_pin_pinalarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     // First, check to see if we match any given alarms.
     for (size_t i = 0; i < n_alarms; i++) {
         if (!mp_obj_is_type(alarms[i], &alarm_pin_pinalarm_type)) {
@@ -101,6 +101,10 @@ mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *al
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
+
+mp_obj_t alarm_pin_pinalarm_create_wakeup_alarm(void) {
     alarm_pin_pinalarm_obj_t *alarm = m_new_obj(alarm_pin_pinalarm_obj_t);
     alarm->base.type = &alarm_pin_pinalarm_type;
     alarm->pin = NULL;
diff --git a/ports/nrf/common-hal/alarm/pin/PinAlarm.h b/ports/nrf/common-hal/alarm/pin/PinAlarm.h
index 42f9f115c8..87b7b9833c 100644
--- a/ports/nrf/common-hal/alarm/pin/PinAlarm.h
+++ b/ports/nrf/common-hal/alarm/pin/PinAlarm.h
@@ -34,8 +34,10 @@ typedef struct {
     bool pull;
 } alarm_pin_pinalarm_obj_t;
 
+mp_obj_t alarm_pin_pinalarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_pin_pinalarm_create_wakeup_alarm(void);
+
 void alarm_pin_pinalarm_reset(void);
 void alarm_pin_pinalarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
 void alarm_pin_pinalarm_prepare_for_deep_sleep(void);
-mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms);
-bool alarm_pin_pinalarm_woke_us_up(void);
+bool alarm_pin_pinalarm_woke_this_cycle(void);
diff --git a/ports/nrf/common-hal/alarm/time/TimeAlarm.c b/ports/nrf/common-hal/alarm/time/TimeAlarm.c
index 1d30065529..54d9a8921f 100644
--- a/ports/nrf/common-hal/alarm/time/TimeAlarm.c
+++ b/ports/nrf/common-hal/alarm/time/TimeAlarm.c
@@ -40,13 +40,16 @@ mp_float_t common_hal_alarm_time_timealarm_get_monotonic_time(alarm_time_timeala
     return self->monotonic_time;
 }
 
-mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms) {
-    // First, check to see if we match
+mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     for (size_t i = 0; i < n_alarms; i++) {
         if (mp_obj_is_type(alarms[i], &alarm_time_timealarm_type)) {
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
+
+mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void) {
     alarm_time_timealarm_obj_t *timer = m_new_obj(alarm_time_timealarm_obj_t);
     timer->base.type = &alarm_time_timealarm_type;
     // TODO: Set monotonic_time based on the RTC state.
@@ -54,7 +57,7 @@ mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *
     return timer;
 }
 
-bool alarm_time_timealarm_woke_us_up(void) {
+bool alarm_time_timealarm_woke_this_cycle(void) {
     return sleepmem_wakeup_event == SLEEPMEM_WAKEUP_BY_TIMER;
 }
 
diff --git a/ports/nrf/common-hal/alarm/time/TimeAlarm.h b/ports/nrf/common-hal/alarm/time/TimeAlarm.h
index 2f65764e19..a2c33be6fb 100644
--- a/ports/nrf/common-hal/alarm/time/TimeAlarm.h
+++ b/ports/nrf/common-hal/alarm/time/TimeAlarm.h
@@ -36,10 +36,11 @@ extern volatile int rtc_woke_up_counter;
 extern void port_disable_interrupt_after_ticks_ch(uint32_t channel);
 extern void port_interrupt_after_ticks_ch(uint32_t channel, uint32_t ticks);
 
-// Find the alarm object that caused us to wake up or create an equivalent one.
-mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void);
+
 // Check for the wake up alarm from pretend deep sleep.
-bool alarm_time_timealarm_woke_us_up(void);
+bool alarm_time_timealarm_woke_this_cycle(void);
 void alarm_time_timealarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
 void alarm_time_timealarm_reset(void);
 
diff --git a/ports/nrf/common-hal/alarm/touch/TouchAlarm.c b/ports/nrf/common-hal/alarm/touch/TouchAlarm.c
index 2d7ee89bd3..f8daf50f54 100644
--- a/ports/nrf/common-hal/alarm/touch/TouchAlarm.c
+++ b/ports/nrf/common-hal/alarm/touch/TouchAlarm.c
@@ -35,7 +35,11 @@ void common_hal_alarm_touch_touchalarm_construct(alarm_touch_touchalarm_obj_t *s
     (void)pin;
 }
 
-mp_obj_t alarm_touch_touchalarm_get_wakeup_alarm(const size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t alarm_touch_touchalarm_find_triggered_alarm(const size_t n_alarms, const mp_obj_t *alarms) {
+    return mp_const_none;
+}
+
+mp_obj_t alarm_touch_touchalarm_create_wakeup_alarm(void) {
     return mp_const_none;
 }
 
@@ -45,7 +49,7 @@ void alarm_touch_touchalarm_set_alarm(const bool deep_sleep, const size_t n_alar
 void alarm_touch_touchalarm_prepare_for_deep_sleep(void) {
 }
 
-bool alarm_touch_touchalarm_woke_us_up(void) {
+bool alarm_touch_touchalarm_woke_this_cycle(void) {
     return false;
 }
 
diff --git a/ports/nrf/common-hal/alarm/touch/TouchAlarm.h b/ports/nrf/common-hal/alarm/touch/TouchAlarm.h
index 755a3977ad..58ad8c20fe 100644
--- a/ports/nrf/common-hal/alarm/touch/TouchAlarm.h
+++ b/ports/nrf/common-hal/alarm/touch/TouchAlarm.h
@@ -36,11 +36,12 @@ typedef struct {
 } alarm_touch_touchalarm_obj_t;
 
 // Find the alarm object that caused us to wake up or create an equivalent one.
-mp_obj_t alarm_touch_touchalarm_get_wakeup_alarm(const size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_touch_touchalarm_find_triggered_alarm(const size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_touch_touchalarm_create_wakeup_alarm(void);
 // Check for the wake up alarm from pretend deep sleep.
 void alarm_touch_touchalarm_set_alarm(const bool deep_sleep, const size_t n_alarms, const mp_obj_t *alarms);
 void alarm_touch_touchalarm_prepare_for_deep_sleep(void);
-bool alarm_touch_touchalarm_woke_us_up(void);
+bool alarm_touch_touchalarm_woke_this_cycle(void);
 void alarm_touch_touchalarm_reset(void);
 
 #endif  // MICROPY_INCLUDED_COMMON_HAL_ALARM_TOUCH_TOUCHALARM_H
diff --git a/ports/stm/common-hal/alarm/__init__.c b/ports/stm/common-hal/alarm/__init__.c
index e0b900bbfc..70a2c63e56 100644
--- a/ports/stm/common-hal/alarm/__init__.c
+++ b/ports/stm/common-hal/alarm/__init__.c
@@ -48,10 +48,8 @@ const alarm_sleep_memory_obj_t alarm_sleep_memory_obj = {
 };
 
 STATIC stm_sleep_source_t true_deep_wake_reason;
-STATIC mp_obj_t most_recent_alarm;
 
 void alarm_reset(void) {
-    most_recent_alarm = NULL;
     // Reset the alarm flag
     STM_ALARM_FLAG = 0x00;
     alarm_pin_pinalarm_reset();
@@ -66,10 +64,10 @@ void alarm_set_wakeup_reason(stm_sleep_source_t reason) {
 
 STATIC stm_sleep_source_t _get_wakeup_cause(void) {
     // If in light/fake sleep, check modules
-    if (alarm_pin_pinalarm_woke_us_up()) {
+    if (alarm_pin_pinalarm_woke_this_cycle()) {
         return STM_WAKEUP_GPIO;
     }
-    if (alarm_time_timealarm_woke_us_up()) {
+    if (alarm_time_timealarm_woke_this_cycle()) {
         return STM_WAKEUP_RTC;
     }
     // Check to see if we woke from deep sleep (reason set in port_init)
@@ -83,14 +81,16 @@ bool common_hal_alarm_woken_from_sleep(void) {
     return _get_wakeup_cause() != STM_WAKEUP_UNDEF;
 }
 
-STATIC mp_obj_t _get_wake_alarm(size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t common_hal_alarm_create_wake_alarm(void) {
+    // If woken from deep sleep, create a copy alarm similar to what would have
+    // been passed in originally. Otherwise, just return none
     stm_sleep_source_t cause = _get_wakeup_cause();
     switch (cause) {
         case STM_WAKEUP_RTC: {
-            return alarm_time_timealarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_time_timealarm_create_wakeup_alarm();
         }
         case STM_WAKEUP_GPIO: {
-            return alarm_pin_pinalarm_get_wakeup_alarm(n_alarms, alarms);
+            return alarm_pin_pinalarm_create_wakeup_alarm();
         }
         case STM_WAKEUP_UNDEF:
         default:
@@ -100,58 +100,51 @@ STATIC mp_obj_t _get_wake_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     return mp_const_none;
 }
 
-mp_obj_t common_hal_alarm_get_wake_alarm(void) {
-    // If we woke from light sleep, override with that alarm
-    if (most_recent_alarm != NULL) {
-        return most_recent_alarm;
-    }
-    return _get_wake_alarm(0, NULL);
-}
-
 // Set up light sleep or deep sleep alarms.
 STATIC void _setup_sleep_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms) {
     alarm_pin_pinalarm_set_alarms(deep_sleep, n_alarms, alarms);
     alarm_time_timealarm_set_alarms(deep_sleep, n_alarms, alarms);
 }
 
-STATIC void _idle_until_alarm(void) {
-    // Poll for alarms.
+mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const mp_obj_t *alarms) {
+    _setup_sleep_alarms(false, n_alarms, alarms);
+    mp_obj_t wake_alarm = mp_const_none;
+
+    // TODO: add more dynamic clock shutdown/restart logic
     while (!mp_hal_is_interrupted()) {
         RUN_BACKGROUND_TASKS;
         // Detect if interrupt was alarm or ctrl-C interrupt.
         if (common_hal_alarm_woken_from_sleep()) {
-            return;
+            stm_sleep_source_t cause = _get_wakeup_cause();
+            switch (cause) {
+                case STM_WAKEUP_RTC: {
+                    wake_alarm = alarm_time_timealarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                case STM_WAKEUP_GPIO: {
+                    wake_alarm = alarm_pin_pinalarm_find_triggered_alarm(n_alarms,alarms);
+                    break;
+                }
+                default:
+                    // Should not reach this, if all light sleep types are covered correctly
+                    break;
+            }
+            shared_alarm_save_wake_alarm(wake_alarm);
+            break;
         }
+        // HAL_PWR_EnterSLEEPMode is just a WFI anyway so don't bother
         port_idle_until_interrupt();
     }
-}
 
-mp_obj_t common_hal_alarm_light_sleep_until_alarms(size_t n_alarms, const mp_obj_t *alarms) {
-    // If USB is active, only pretend to sleep. Otherwise, light sleep
-    if (supervisor_workflow_active()) {
-        _setup_sleep_alarms(false, n_alarms, alarms);
-        _idle_until_alarm();
-    } else {
-        _setup_sleep_alarms(false, n_alarms, alarms);
-        port_disable_tick();
-        HAL_PWR_EnterSLEEPMode(PWR_MAINREGULATOR_ON, PWR_SLEEPENTRY_WFI);
-        port_enable_tick();
+    if (mp_hal_is_interrupted()) {
+        return mp_const_none; // Shouldn't be given to python code because exception handling should kick in.
     }
 
-    mp_obj_t wake_alarm = _get_wake_alarm(n_alarms, alarms);
-
-    // TODO: make assignment to global array less roundabout
-    most_recent_alarm = wake_alarm;
-    shared_alarm_save_wake_alarm();
-
-    // Can't use alarm_reset since it resets most_recent_alarm
-    alarm_pin_pinalarm_reset();
-    alarm_time_timealarm_reset();
+    alarm_reset();
     return wake_alarm;
 }
 
 void common_hal_alarm_set_deep_sleep_alarms(size_t n_alarms, const mp_obj_t *alarms) {
-    most_recent_alarm = NULL;
     _setup_sleep_alarms(true, n_alarms, alarms);
 }
 
diff --git a/ports/stm/common-hal/alarm/pin/PinAlarm.c b/ports/stm/common-hal/alarm/pin/PinAlarm.c
index 381a13b220..799922ae8f 100644
--- a/ports/stm/common-hal/alarm/pin/PinAlarm.c
+++ b/ports/stm/common-hal/alarm/pin/PinAlarm.c
@@ -85,11 +85,11 @@ bool common_hal_alarm_pin_pinalarm_get_pull(alarm_pin_pinalarm_obj_t *self) {
     return self->pull;
 }
 
-bool alarm_pin_pinalarm_woke_us_up(void) {
+bool alarm_pin_pinalarm_woke_this_cycle(void) {
     return woke_up;
 }
 
-mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t alarm_pin_pinalarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     for (size_t i = 0; i < n_alarms; i++) {
         if (!mp_obj_is_type(alarms[i], &alarm_pin_pinalarm_type)) {
             continue;
@@ -99,8 +99,10 @@ mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *al
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
 
-    // If the above isn't true, we woke from deep sleep, so create a new alarm
+mp_obj_t alarm_pin_pinalarm_create_wakeup_alarm(void) {
     alarm_pin_pinalarm_obj_t *alarm = m_new_obj(alarm_pin_pinalarm_obj_t);
     alarm->base.type = &alarm_pin_pinalarm_type;
     // TODO: replace this if/when other WKUP pins are supported
diff --git a/ports/stm/common-hal/alarm/pin/PinAlarm.h b/ports/stm/common-hal/alarm/pin/PinAlarm.h
index bd18c840ff..bc52849a53 100644
--- a/ports/stm/common-hal/alarm/pin/PinAlarm.h
+++ b/ports/stm/common-hal/alarm/pin/PinAlarm.h
@@ -37,10 +37,12 @@ typedef struct {
     bool pull;
 } alarm_pin_pinalarm_obj_t;
 
+mp_obj_t alarm_pin_pinalarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_pin_pinalarm_create_wakeup_alarm(void);
+
 void alarm_pin_pinalarm_reset(void);
 void alarm_pin_pinalarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
 void alarm_pin_pinalarm_prepare_for_deep_sleep(void);
-mp_obj_t alarm_pin_pinalarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms);
-bool alarm_pin_pinalarm_woke_us_up(void);
+bool alarm_pin_pinalarm_woke_this_cycle(void);
 
 #endif  // MICROPY_INCLUDED_STM32_COMMON_HAL_ALARM_PINALARM_H
diff --git a/ports/stm/common-hal/alarm/time/TimeAlarm.c b/ports/stm/common-hal/alarm/time/TimeAlarm.c
index 2c38066d3a..6fb1fc629d 100644
--- a/ports/stm/common-hal/alarm/time/TimeAlarm.c
+++ b/ports/stm/common-hal/alarm/time/TimeAlarm.c
@@ -44,13 +44,17 @@ mp_float_t common_hal_alarm_time_timealarm_get_monotonic_time(alarm_time_timeala
     return self->monotonic_time;
 }
 
-mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms) {
+mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms) {
     // First, check to see if we match
     for (size_t i = 0; i < n_alarms; i++) {
         if (mp_obj_is_type(alarms[i], &alarm_time_timealarm_type)) {
             return alarms[i];
         }
     }
+    return mp_const_none;
+}
+
+mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void) {
     alarm_time_timealarm_obj_t *timer = m_new_obj(alarm_time_timealarm_obj_t);
     timer->base.type = &alarm_time_timealarm_type;
     // TODO: Set monotonic_time based on the RTC state.
@@ -63,7 +67,7 @@ STATIC void timer_callback(void) {
     woke_up = true;
 }
 
-bool alarm_time_timealarm_woke_us_up(void) {
+bool alarm_time_timealarm_woke_this_cycle(void) {
     return woke_up;
 }
 
diff --git a/ports/stm/common-hal/alarm/time/TimeAlarm.h b/ports/stm/common-hal/alarm/time/TimeAlarm.h
index 0d0c25deae..1dd217edd6 100644
--- a/ports/stm/common-hal/alarm/time/TimeAlarm.h
+++ b/ports/stm/common-hal/alarm/time/TimeAlarm.h
@@ -34,10 +34,11 @@ typedef struct {
     mp_float_t monotonic_time;      // values compatible with time.monotonic_time()
 } alarm_time_timealarm_obj_t;
 
-// Find the alarm object that caused us to wake up or create an equivalent one.
-mp_obj_t alarm_time_timealarm_get_wakeup_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
+mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void);
+
 // Check for the wake up alarm from pretend deep sleep.
-bool alarm_time_timealarm_woke_us_up(void);
+bool alarm_time_timealarm_woke_this_cycle(void);
 void alarm_time_timealarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
 void alarm_time_timealarm_reset(void);
 

From bce541dcc5a3c95902780de697c51818bd2cbaa3 Mon Sep 17 00:00:00 2001
From: Lucian Copeland <hierophect@gmail.com>
Date: Tue, 18 May 2021 15:16:25 -0400
Subject: [PATCH 3/3] Minor text fixes

---
 ports/nrf/common-hal/alarm/time/TimeAlarm.h | 1 -
 ports/stm/common-hal/alarm/time/TimeAlarm.h | 1 -
 2 files changed, 2 deletions(-)

diff --git a/ports/nrf/common-hal/alarm/time/TimeAlarm.h b/ports/nrf/common-hal/alarm/time/TimeAlarm.h
index a2c33be6fb..734feb1c87 100644
--- a/ports/nrf/common-hal/alarm/time/TimeAlarm.h
+++ b/ports/nrf/common-hal/alarm/time/TimeAlarm.h
@@ -39,7 +39,6 @@ extern void port_interrupt_after_ticks_ch(uint32_t channel, uint32_t ticks);
 mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
 mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void);
 
-// Check for the wake up alarm from pretend deep sleep.
 bool alarm_time_timealarm_woke_this_cycle(void);
 void alarm_time_timealarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
 void alarm_time_timealarm_reset(void);
diff --git a/ports/stm/common-hal/alarm/time/TimeAlarm.h b/ports/stm/common-hal/alarm/time/TimeAlarm.h
index 1dd217edd6..48531ebdf6 100644
--- a/ports/stm/common-hal/alarm/time/TimeAlarm.h
+++ b/ports/stm/common-hal/alarm/time/TimeAlarm.h
@@ -37,7 +37,6 @@ typedef struct {
 mp_obj_t alarm_time_timealarm_find_triggered_alarm(size_t n_alarms, const mp_obj_t *alarms);
 mp_obj_t alarm_time_timealarm_create_wakeup_alarm(void);
 
-// Check for the wake up alarm from pretend deep sleep.
 bool alarm_time_timealarm_woke_this_cycle(void);
 void alarm_time_timealarm_set_alarms(bool deep_sleep, size_t n_alarms, const mp_obj_t *alarms);
 void alarm_time_timealarm_reset(void);