From 6f0274f4b95770d64eed8e7a22c5d54d9171d1f3 Mon Sep 17 00:00:00 2001
From: thisiskeithb <13375512+thisiskeithb@users.noreply.github.com>
Date: Wed, 8 Feb 2023 23:23:46 -0800
Subject: [PATCH] Fix TOUCH_SCREEN_CALIBRATION Invalid First Point

Avoid registering first touch point as top-left corner when initiating touch calibration since user is touching TFT
---
 Marlin/src/lcd/tft_io/touch_calibration.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Marlin/src/lcd/tft_io/touch_calibration.cpp b/Marlin/src/lcd/tft_io/touch_calibration.cpp
index 44ebc73d71a26..5f45a9506df2c 100644
--- a/Marlin/src/lcd/tft_io/touch_calibration.cpp
+++ b/Marlin/src/lcd/tft_io/touch_calibration.cpp
@@ -92,6 +92,13 @@ void TouchCalibration::validate_calibration() {
 bool TouchCalibration::handleTouch(uint16_t x, uint16_t y) {
   static millis_t next_button_update_ms = 0;
   const millis_t now = millis();
+
+  // Avoid registering first touch point as top-left corner when initiating touch calibration since user is touching TFT
+  if (next_button_update_ms == 0) {
+    next_button_update_ms = now + BUTTON_DELAY_MENU;
+    return true;
+  }
+
   if (PENDING(now, next_button_update_ms)) return false;
   next_button_update_ms = now + BUTTON_DELAY_MENU;