TMC SPI Endstops and Improved Sensorless Homing (#14044)

Marlin/src/module/endstops.h

@@ -161,6 +161,18 @@ class Endstops {
       static void monitor();
       static void run_monitor();
     #endif
+
+    #if ENABLED(SPI_ENDSTOPS)
+      typedef struct {
+        union {
+          bool any;
+          struct { bool x:1, y:1, z:1; };
+        };
+      } tmc_spi_homing_t;
+      static tmc_spi_homing_t tmc_spi_homing;
+      static void clear_endstop_state();
+      static bool tmc_spi_homing_check();
+    #endif
 };
 
 extern Endstops endstops;