diff --git a/Marlin/src/Marlin.cpp b/Marlin/src/Marlin.cpp
index c248e4814b..d1f5fe53b6 100644
--- a/Marlin/src/Marlin.cpp
+++ b/Marlin/src/Marlin.cpp
@@ -687,9 +687,12 @@ void idle(
 
   #if ENABLED(I2C_POSITION_ENCODERS)
     static millis_t i2cpem_next_update_ms;
-    if (planner.has_blocks_queued() && ELAPSED(millis(), i2cpem_next_update_ms)) {
-      I2CPEM.update();
-      i2cpem_next_update_ms = millis() + I2CPE_MIN_UPD_TIME_MS;
+    if (planner.has_blocks_queued()) {
+      const millis_t ms = millis();
+      if (ELAPSED(ms, i2cpem_next_update_ms)) {
+        I2CPEM.update();
+        i2cpem_next_update_ms = ms + I2CPE_MIN_UPD_TIME_MS;
+      }
     }
   #endif
 
diff --git a/Marlin/src/feature/tmc_util.h b/Marlin/src/feature/tmc_util.h
index 1df9a1a3b3..a3eb49a1e0 100644
--- a/Marlin/src/feature/tmc_util.h
+++ b/Marlin/src/feature/tmc_util.h
@@ -348,17 +348,15 @@ void test_tmc_connection(const bool test_x, const bool test_y, const bool test_z
 #endif
 
 /**
- * TMC2130 specific sensorless homing using stallGuard2.
+ * TMC2130-specific sensorless homing using stallGuard2.
  * stallGuard2 only works when in spreadCycle mode.
- * spreadCycle and stealthChop are mutually exclusive.
+ * spreadCycle and stealthChop are mutually-exclusive.
  *
  * Defined here because of limitations with templates and headers.
  */
 #if USE_SENSORLESS
   // Track enabled status of stealthChop and only re-enable where applicable
-  struct sensorless_t {
-    bool x, y, z, x2, y2, z2, z3;
-  };
+  struct sensorless_t { bool x, y, z, x2, y2, z2, z3; };
 
   bool tmc_enable_stallguard(TMC2130Stepper &st);
   void tmc_disable_stallguard(TMC2130Stepper &st, const bool restore_stealth);
diff --git a/Marlin/src/gcode/calibrate/G28.cpp b/Marlin/src/gcode/calibrate/G28.cpp
index 8e12f4b06a..f39d3bae10 100644
--- a/Marlin/src/gcode/calibrate/G28.cpp
+++ b/Marlin/src/gcode/calibrate/G28.cpp
@@ -78,7 +78,7 @@
                 fr_mm_s = _MIN(homing_feedrate(X_AXIS), homing_feedrate(Y_AXIS)) * SQRT(sq(mlratio) + 1.0);
 
     #if ENABLED(SENSORLESS_HOMING)
-      sensorless_t stealth_states { false, false, false, false, false, false, false };
+      sensorless_t stealth_states { false };
       stealth_states.x = tmc_enable_stallguard(stepperX);
       stealth_states.y = tmc_enable_stallguard(stepperY);
       #if AXIS_HAS_STALLGUARD(X2)
diff --git a/Marlin/src/gcode/config/M200-M205.cpp b/Marlin/src/gcode/config/M200-M205.cpp
index 3e96641474..c43b889244 100644
--- a/Marlin/src/gcode/config/M200-M205.cpp
+++ b/Marlin/src/gcode/config/M200-M205.cpp
@@ -65,7 +65,7 @@ void GcodeSuite::M201() {
       planner.settings.max_acceleration_mm_per_s2[a] = parser.value_axis_units((AxisEnum)a);
     }
   }
-  // steps per sq second need to be updated to agree with the units per sq second (as they are what is used in the planner)
+
   planner.reset_acceleration_rates();
 }
 
diff --git a/Marlin/src/inc/SanityCheck.h b/Marlin/src/inc/SanityCheck.h
index d4c7467c67..f362ba8730 100644
--- a/Marlin/src/inc/SanityCheck.h
+++ b/Marlin/src/inc/SanityCheck.h
@@ -2060,22 +2060,24 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
 
   #if ENABLED(DELTA) && !BOTH(STEALTHCHOP_XY, STEALTHCHOP_Z)
     #error "SENSORLESS_HOMING on DELTA currently requires STEALTHCHOP_XY and STEALTHCHOP_Z."
-  #elif X_SENSORLESS && X_HOME_DIR == -1 && (X_MIN_ENDSTOP_INVERTING != X_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_XMIN))
-    #error "SENSORLESS_HOMING requires X_MIN_ENDSTOP_INVERTING and ENDSTOPPULLUP_XMIN when homing to X_MIN."
-  #elif X_SENSORLESS && X_HOME_DIR ==  1 && (X_MAX_ENDSTOP_INVERTING != X_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_XMAX))
-    #error "SENSORLESS_HOMING requires X_MAX_ENDSTOP_INVERTING and ENDSTOPPULLUP_XMAX when homing to X_MAX."
-  #elif Y_SENSORLESS && Y_HOME_DIR == -1 && (Y_MIN_ENDSTOP_INVERTING != Y_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_YMIN))
-    #error "SENSORLESS_HOMING requires Y_MIN_ENDSTOP_INVERTING and ENDSTOPPULLUP_YMIN when homing to Y_MIN."
-  #elif Y_SENSORLESS && Y_HOME_DIR ==  1 && (Y_MAX_ENDSTOP_INVERTING != Y_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_YMAX))
-    #error "SENSORLESS_HOMING requires Y_MAX_ENDSTOP_INVERTING and ENDSTOPPULLUP_YMAX when homing to Y_MAX."
-  #elif Z_SENSORLESS && Z_HOME_DIR == -1 && (Z_MIN_ENDSTOP_INVERTING != Z_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_ZMIN))
-    #error "SENSORLESS_HOMING requires Z_MIN_ENDSTOP_INVERTING and ENDSTOPPULLUP_ZMIN when homing to Z_MIN."
-  #elif Z_SENSORLESS && Z_HOME_DIR ==  1 && (Z_MAX_ENDSTOP_INVERTING != Z_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_ZMAX))
-    #error "SENSORLESS_HOMING requires Z_MAX_ENDSTOP_INVERTING and ENDSTOPPULLUP_ZMAX when homing to Z_MAX."
   #elif ENDSTOP_NOISE_THRESHOLD
     #error "SENSORLESS_HOMING is incompatible with ENDSTOP_NOISE_THRESHOLD."
   #elif !(X_SENSORLESS || Y_SENSORLESS || Z_SENSORLESS)
     #error "SENSORLESS_HOMING requires a TMC stepper driver with StallGuard on X, Y, or Z axes."
+  #elif DISABLED(SPI_ENDSTOPS)
+    #if   X_SENSORLESS && X_HOME_DIR < 0 && (X_MIN_ENDSTOP_INVERTING != X_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_XMIN))
+      #error "SENSORLESS_HOMING requires X_MIN_ENDSTOP_INVERTING and ENDSTOPPULLUP_XMIN when homing to X_MIN."
+    #elif X_SENSORLESS && X_HOME_DIR > 0 && (X_MAX_ENDSTOP_INVERTING != X_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_XMAX))
+      #error "SENSORLESS_HOMING requires X_MAX_ENDSTOP_INVERTING and ENDSTOPPULLUP_XMAX when homing to X_MAX."
+    #elif Y_SENSORLESS && Y_HOME_DIR < 0 && (Y_MIN_ENDSTOP_INVERTING != Y_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_YMIN))
+      #error "SENSORLESS_HOMING requires Y_MIN_ENDSTOP_INVERTING and ENDSTOPPULLUP_YMIN when homing to Y_MIN."
+    #elif Y_SENSORLESS && Y_HOME_DIR > 0 && (Y_MAX_ENDSTOP_INVERTING != Y_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_YMAX))
+      #error "SENSORLESS_HOMING requires Y_MAX_ENDSTOP_INVERTING and ENDSTOPPULLUP_YMAX when homing to Y_MAX."
+    #elif Z_SENSORLESS && Z_HOME_DIR < 0 && (Z_MIN_ENDSTOP_INVERTING != Z_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_ZMIN))
+      #error "SENSORLESS_HOMING requires Z_MIN_ENDSTOP_INVERTING and ENDSTOPPULLUP_ZMIN when homing to Z_MIN."
+    #elif Z_SENSORLESS && Z_HOME_DIR > 0 && (Z_MAX_ENDSTOP_INVERTING != Z_ENDSTOP_INVERTING || DISABLED(ENDSTOPPULLUP_ZMAX))
+      #error "SENSORLESS_HOMING requires Z_MAX_ENDSTOP_INVERTING and ENDSTOPPULLUP_ZMAX when homing to Z_MAX."
+    #endif
   #endif
 
   #undef X_ENDSTOP_INVERTING
diff --git a/Marlin/src/module/delta.cpp b/Marlin/src/module/delta.cpp
index 466f552274..51f20b2519 100644
--- a/Marlin/src/module/delta.cpp
+++ b/Marlin/src/module/delta.cpp
@@ -227,7 +227,7 @@ void home_delta() {
 
   // Disable stealthChop if used. Enable diag1 pin on driver.
   #if ENABLED(SENSORLESS_HOMING)
-    sensorless_t stealth_states { false, false, false, false, false, false, false };
+    sensorless_t stealth_states { false };
     stealth_states.x = tmc_enable_stallguard(stepperX);
     stealth_states.y = tmc_enable_stallguard(stepperY);
     stealth_states.z = tmc_enable_stallguard(stepperZ);
diff --git a/Marlin/src/module/endstops.cpp b/Marlin/src/module/endstops.cpp
index 7234bf4769..abc93e9f1d 100644
--- a/Marlin/src/module/endstops.cpp
+++ b/Marlin/src/module/endstops.cpp
@@ -783,14 +783,13 @@ void Endstops::update() {
   bool Endstops::monitor_flag = false;
 
   /**
-   * monitors endstops & Z probe for changes
+   * Monitor Endstops and Z Probe for changes
    *
    * If a change is detected then the LED is toggled and
-   * a message is sent out the serial port
+   * a message is sent out the serial port.
    *
    * Yes, we could miss a rapid back & forth change but
    * that won't matter because this is all manual.
-   *
    */
   void Endstops::monitor() {
 
diff --git a/Marlin/src/module/endstops.h b/Marlin/src/module/endstops.h
index d20e61f702..604befdbb9 100644
--- a/Marlin/src/module/endstops.h
+++ b/Marlin/src/module/endstops.h
@@ -29,27 +29,16 @@
 #include <stdint.h>
 
 enum EndstopEnum : char {
-  X_MIN,
-  Y_MIN,
-  Z_MIN,
-  Z_MIN_PROBE,
-  X_MAX,
-  Y_MAX,
-  Z_MAX,
-  X2_MIN,
-  X2_MAX,
-  Y2_MIN,
-  Y2_MAX,
-  Z2_MIN,
-  Z2_MAX,
-  Z3_MIN,
-  Z3_MAX
+  X_MIN,  Y_MIN,  Z_MIN,  Z_MIN_PROBE,
+  X_MAX,  Y_MAX,  Z_MAX,
+  X2_MIN, X2_MAX,
+  Y2_MIN, Y2_MAX,
+  Z2_MIN, Z2_MAX,
+  Z3_MIN, Z3_MAX
 };
 
 class Endstops {
-
   public:
-
     #if HAS_EXTRA_ENDSTOPS
       typedef uint16_t esbits_t;
       #if ENABLED(X_DUAL_ENDSTOPS)
diff --git a/Marlin/src/module/motion.cpp b/Marlin/src/module/motion.cpp
index ee46fc3f99..69b5905b20 100644
--- a/Marlin/src/module/motion.cpp
+++ b/Marlin/src/module/motion.cpp
@@ -1071,7 +1071,7 @@ float get_homing_bump_feedrate(const AxisEnum axis) {
    * Set sensorless homing if the axis has it, accounting for Core Kinematics.
    */
   sensorless_t start_sensorless_homing_per_axis(const AxisEnum axis) {
-    sensorless_t stealth_states { false, false, false, false, false, false, false };
+    sensorless_t stealth_states { false };
 
     switch (axis) {
       default: break;
diff --git a/Marlin/src/module/probe.cpp b/Marlin/src/module/probe.cpp
index dbd14ed5b5..2d29084367 100644
--- a/Marlin/src/module/probe.cpp
+++ b/Marlin/src/module/probe.cpp
@@ -540,7 +540,7 @@ static bool do_probe_move(const float z, const float fr_mm_s) {
 
   // Disable stealthChop if used. Enable diag1 pin on driver.
   #if ENABLED(SENSORLESS_PROBING)
-    sensorless_t stealth_states { false, false, false, false, false, false, false };
+    sensorless_t stealth_states { false };
     #if ENABLED(DELTA)
       stealth_states.x = tmc_enable_stallguard(stepperX);
       stealth_states.y = tmc_enable_stallguard(stepperY);