From 01ea0e44bda63e9a3f21b6ce8bdfb7b0461f4676 Mon Sep 17 00:00:00 2001
From: Peter Johanson <peter@peterjohanson.com>
Date: Sun, 23 Apr 2023 07:10:48 +0000
Subject: [PATCH] refactor(underglow): Add runtime device PM support

* Properly get/put the LED strip instance when actively using
  the LEDs, to allow automatic power domain handling to cut
  power when the LEDs are not in use.
---
 app/Kconfig             |  2 +-
 app/src/rgb_underglow.c | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/app/Kconfig b/app/Kconfig
index a45f2dc2..86ff0461 100644
--- a/app/Kconfig
+++ b/app/Kconfig
@@ -275,7 +275,7 @@ config SPI
 
 config ZMK_RGB_UNDERGLOW_EXT_POWER
     bool "RGB underglow toggling also controls external power"
-    default y
+    default y if !POWER_DOMAIN
 
 config ZMK_RGB_UNDERGLOW_BRT_MIN
     int "RGB underglow minimum brightness in percent"
diff --git a/app/src/rgb_underglow.c b/app/src/rgb_underglow.c
index 3453fb44..7f5bdc54 100644
--- a/app/src/rgb_underglow.c
+++ b/app/src/rgb_underglow.c
@@ -7,6 +7,7 @@
 #include <zephyr/device.h>
 #include <zephyr/init.h>
 #include <zephyr/kernel.h>
+#include <zephyr/pm/device_runtime.h>
 #include <zephyr/settings/settings.h>
 
 #include <math.h>
@@ -274,6 +275,7 @@ static int zmk_rgb_underglow_init(void) {
 #endif
 
     if (state.on) {
+        pm_device_runtime_get(led_strip);
         k_timer_start(&underglow_tick, K_NO_WAIT, K_MSEC(50));
     }
 
@@ -300,6 +302,14 @@ int zmk_rgb_underglow_get_state(bool *on_off) {
 int zmk_rgb_underglow_on(void) {
     if (!led_strip)
         return -ENODEV;
+    }
+
+    // Newer PM device approach to ensuring powered on when used.
+    const int rc = pm_device_runtime_get(led_strip);
+    if (rc < 0) {
+        LOG_ERR("Failed to enable/get the PM device (%d)", rc);
+        return rc;
+    }
 
 #if IS_ENABLED(CONFIG_ZMK_RGB_UNDERGLOW_EXT_POWER)
     if (ext_power != NULL) {
@@ -345,6 +355,8 @@ int zmk_rgb_underglow_off(void) {
     k_timer_stop(&underglow_tick);
     state.on = false;
 
+    pm_device_runtime_put(led_strip);
+
     return zmk_rgb_underglow_save_state();
 }