From 0c5fd55c166a78cd7ee4f0e68f2ec8ca89fc182b Mon Sep 17 00:00:00 2001
From: Jeff Epler <jepler@gmail.com>
Date: Thu, 13 Oct 2022 20:09:48 -0500
Subject: [PATCH] picow: Turn off wifi co-processor regulator when entering
 deep sleep

This reduces power consumption during true deep sleep.

In my measurements with ppk2 and a program that _irrevocably_ entered
deep sleep (no time alarm or pin alarm), power usage as measured on a
ppk2 decreased from ~10mA to ~1mA.
---
 ports/raspberrypi/bindings/cyw43/__init__.c   | 6 ++++++
 ports/raspberrypi/bindings/cyw43/__init__.h   | 1 +
 ports/raspberrypi/common-hal/alarm/__init__.c | 8 ++++++++
 3 files changed, 15 insertions(+)

diff --git a/ports/raspberrypi/bindings/cyw43/__init__.c b/ports/raspberrypi/bindings/cyw43/__init__.c
index 66cc5fa1c4..bf0cbc2e67 100644
--- a/ports/raspberrypi/bindings/cyw43/__init__.c
+++ b/ports/raspberrypi/bindings/cyw43/__init__.c
@@ -35,6 +35,12 @@
 
 static int power_management_value = PM_DISABLED;
 
+void cyw43_enter_deep_sleep(void) {
+#define WL_REG_ON 23
+    gpio_set_dir(WL_REG_ON, GPIO_OUT);
+    gpio_put(WL_REG_ON, false);
+}
+
 void bindings_cyw43_wifi_enforce_pm() {
     cyw43_wifi_pm(&cyw43_state, power_management_value);
 }
diff --git a/ports/raspberrypi/bindings/cyw43/__init__.h b/ports/raspberrypi/bindings/cyw43/__init__.h
index c543f7b9e1..2520c6c2d1 100644
--- a/ports/raspberrypi/bindings/cyw43/__init__.h
+++ b/ports/raspberrypi/bindings/cyw43/__init__.h
@@ -51,3 +51,4 @@ const mcu_pin_obj_t *validate_obj_is_pin_including_cyw43(mp_obj_t obj);
 #define PM_DISABLED CONSTANT_CYW43_PM_VALUE(CYW43_NO_POWERSAVE_MODE, 200, 1, 1, 10)
 
 extern void bindings_cyw43_wifi_enforce_pm(void);
+void cyw43_enter_deep_sleep(void);
diff --git a/ports/raspberrypi/common-hal/alarm/__init__.c b/ports/raspberrypi/common-hal/alarm/__init__.c
index 31fa58aab3..9cfa390116 100644
--- a/ports/raspberrypi/common-hal/alarm/__init__.c
+++ b/ports/raspberrypi/common-hal/alarm/__init__.c
@@ -38,6 +38,10 @@
 
 #include "shared-bindings/microcontroller/__init__.h"
 
+#if CIRCUITPY_CYW43
+#include "bindings/cyw43/__init__.h"
+#endif
+
 #include "supervisor/port.h"
 #include "supervisor/shared/workflow.h"
 
@@ -204,6 +208,10 @@ void common_hal_alarm_set_deep_sleep_alarms(size_t n_alarms, const mp_obj_t *ala
 void NORETURN common_hal_alarm_enter_deep_sleep(void) {
     bool timealarm_set = alarm_time_timealarm_is_set();
 
+    #if CIRCUITPY_CYW43
+    cyw43_enter_deep_sleep();
+    #endif
+
     // If there's a timealarm, just enter a very deep light sleep
     if (timealarm_set) {
         // Prune the clock for sleep