# oled ext pwr: Apply ddudek OLED ext pwr patch

This commit properly reinitializes the OLED display after ext power is re-enabled.

It requires a patch pn zephyr itself.

Until the patch is implemented in zephyr, it can be applied in your zmk-config’s github build action.

More info here:
zmkfirmware#674

Original code by ddudek can also be found in the above issue.

These changes are based on infused-kim zmk repo

.gitignore

@@ -7,4 +7,5 @@
 /build
 *.DS_Store
 __pycache__
-.idea
+.idea
+.vscode

app/src/ext_power_generic.c

@@ -15,6 +15,9 @@
 #include <zephyr/drivers/gpio.h>
 
 #include <drivers/ext_power.h>
+#include <drivers/display.h>
+
+#define ZMK_DISPLAY_NAME CONFIG_LVGL_DISPLAY_DEV_NAME
 
 #if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
 
@@ -55,6 +58,16 @@ int ext_power_save_state() {
 #endif
 }
 
+static void drivers_update_power_state(bool power) {
+    LOG_DBG("drivers_update_power_state: %s", power ? "true" : "false");
+    static const struct device *display;
+    display = device_get_binding(ZMK_DISPLAY_NAME);
+
+    if (display != NULL) {
+        display_update_ext_power(display, power);
+    }
+}
+
 static int ext_power_generic_enable(const struct device *dev) {
     struct ext_power_generic_data *data = dev->data;
     const struct ext_power_generic_config *config = dev->config;
@@ -64,6 +77,7 @@ static int ext_power_generic_enable(const struct device *dev) {
         return -EIO;
     }
     data->status = true;
+    drivers_update_power_state(true);
     return ext_power_save_state();
 }
 
@@ -77,6 +91,7 @@ static int ext_power_generic_disable(const struct device *dev) {
         return -EIO;
     }
     data->status = false;
+    drivers_update_power_state(false);
     return ext_power_save_state();
 }