From 796961acecdd450a868f86c9bea370be0ceb17df Mon Sep 17 00:00:00 2001
From: mitchellcairns <mitchellcairns@gmail.com>
Date: Sun, 22 Jun 2025 20:59:15 -0700
Subject: [PATCH] Resolve bug for calibration Nintendo Switch Pro Controller
 (#13260)

Resolves a bug which prevents the stored calibration data from loading, only allowing loading of factory-installed calibration data
---
 src/joystick/hidapi/SDL_hidapi_switch.c | 58 +++++++++++++++----------
 1 file changed, 36 insertions(+), 22 deletions(-)

diff --git a/src/joystick/hidapi/SDL_hidapi_switch.c b/src/joystick/hidapi/SDL_hidapi_switch.c
index e44cf25dd5..36865508b4 100644
--- a/src/joystick/hidapi/SDL_hidapi_switch.c
+++ b/src/joystick/hidapi/SDL_hidapi_switch.c
@@ -928,13 +928,14 @@ static bool SetIMUEnabled(SDL_DriverSwitch_Context *ctx, bool enabled)
 
 static bool LoadStickCalibration(SDL_DriverSwitch_Context *ctx)
 {
-    Uint8 *pLeftStickCal;
-    Uint8 *pRightStickCal;
+    Uint8 *pLeftStickCal = NULL;
+    Uint8 *pRightStickCal = NULL;
     size_t stick, axis;
     SwitchSubcommandInputPacket_t *user_reply = NULL;
     SwitchSubcommandInputPacket_t *factory_reply = NULL;
     SwitchSPIOpData_t readUserParams;
     SwitchSPIOpData_t readFactoryParams;
+    Uint8 userParamsReadSuccessCount = 0;
 
     // Read User Calibration Info
     readUserParams.unAddress = k_unSPIStickUserCalibrationStartOffset;
@@ -947,33 +948,46 @@ static bool LoadStickCalibration(SDL_DriverSwitch_Context *ctx)
     readFactoryParams.unAddress = k_unSPIStickFactoryCalibrationStartOffset;
     readFactoryParams.ucLength = k_unSPIStickFactoryCalibrationLength;
 
-    const int MAX_ATTEMPTS = 3;
-    for (int attempt = 0; ; ++attempt) {
-        if (!WriteSubcommand(ctx, k_eSwitchSubcommandIDs_SPIFlashRead, (uint8_t *)&readFactoryParams, sizeof(readFactoryParams), &factory_reply)) {
-            return false;
-        }
-
-        if (factory_reply->stickFactoryCalibration.opData.unAddress == k_unSPIStickFactoryCalibrationStartOffset) {
-            // We successfully read the calibration data
-            break;
-        }
-
-        if (attempt == MAX_ATTEMPTS) {
-            return false;
-        }
-    }
-
     // Automatically select the user calibration if magic bytes are set
     if (user_reply && user_reply->stickUserCalibration.rgucLeftMagic[0] == 0xB2 && user_reply->stickUserCalibration.rgucLeftMagic[1] == 0xA1) {
+        userParamsReadSuccessCount += 1;
         pLeftStickCal = user_reply->stickUserCalibration.rgucLeftCalibration;
-    } else {
-        pLeftStickCal = factory_reply->stickFactoryCalibration.rgucLeftCalibration;
     }
 
     if (user_reply && user_reply->stickUserCalibration.rgucRightMagic[0] == 0xB2 && user_reply->stickUserCalibration.rgucRightMagic[1] == 0xA1) {
+        userParamsReadSuccessCount += 1;
         pRightStickCal = user_reply->stickUserCalibration.rgucRightCalibration;
-    } else {
-        pRightStickCal = factory_reply->stickFactoryCalibration.rgucRightCalibration;
+    } 
+
+    // Only read the factory calibration info if we failed to receive the correct magic bytes
+    if (userParamsReadSuccessCount < 2) {
+        // Read Factory Calibration Info
+        readFactoryParams.unAddress = k_unSPIStickFactoryCalibrationStartOffset;
+        readFactoryParams.ucLength = k_unSPIStickFactoryCalibrationLength;
+
+        const int MAX_ATTEMPTS = 3;
+        for (int attempt = 0;; ++attempt) {
+            if (!WriteSubcommand(ctx, k_eSwitchSubcommandIDs_SPIFlashRead, (uint8_t *)&readFactoryParams, sizeof(readFactoryParams), &factory_reply)) {
+                return false;
+            }
+
+            if (factory_reply->stickFactoryCalibration.opData.unAddress == k_unSPIStickFactoryCalibrationStartOffset) {
+                // We successfully read the calibration data
+                pLeftStickCal = factory_reply->stickFactoryCalibration.rgucLeftCalibration;
+                pRightStickCal = factory_reply->stickFactoryCalibration.rgucRightCalibration;
+                break;
+            }
+
+            if (attempt == MAX_ATTEMPTS) {
+                return false;
+            }
+        }
+    }
+
+    // If we still don't have calibration data, return false
+    if (pLeftStickCal == NULL || pRightStickCal == NULL)
+    {
+        return false;
     }
 
     /* Stick calibration values are 12-bits each and are packed by bit