endstop_phase: Add support for detecting phase via TMC stepper drivers

The Trinamic stepper motor drivers are capable of reporting the
stepper phase - add support for using that capability to the
enddstop_phases module.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

config/example-extras.cfg

@@ -329,9 +329,11 @@
 # of endstop switches.
 #[endstop_phase stepper_z]
 #phases:
-#   Set this to the number of phases of the given stepper motor driver
-#   (which is the number of micro-steps multiplied by four). This
-#   parameter must be provided.
+#   This specifies the number of phases of the given stepper motor
+#   driver (which is the number of micro-steps multiplied by four).
+#   This setting is automatically determined if one uses TMC2130,
+#   TMC2208, or TMC2224 drivers with run-time configuration.
+#   Otherwise, this parameter must be provided.
 #endstop_accuracy: 0.200
 #   Sets the expected accuracy (in mm) of the endstop. This represents
 #   the maximum error distance the endstop may trigger (eg, if an

klippy/extras/endstop_phase.py

@@ -6,17 +6,30 @@
 import math, logging
 import homing
 
+TRINAMIC_DRIVERS = ["tmc2130", "tmc2208"]
+
 class EndstopPhase:
     def __init__(self, config):
         self.printer = config.get_printer()
         self.name = config.get_name().split()[1]
-        stepper_config = config.getsection(self.name)
-        self.step_dist = step_dist = stepper_config.getfloat('step_distance')
+        # Determine number of stepper phases
+        for driver in TRINAMIC_DRIVERS:
+            driver_name = "%s %s" % (driver, self.name)
+            if config.has_section(driver_name):
+                module = self.printer.try_load_module(config, driver_name)
+                self.get_phase = module.get_phase
+                self.phases = module.get_microsteps() * 4
+                break
+        else:
+            self.get_phase = None
             self.phases = config.getint('phases', minval=1)
+        # Determine endstop phase position
         self.endstop_phase = config.getint('endstop_phase', None,
                                            minval=0, maxval=self.phases-1)
         self.endstop_align_zero = config.getboolean('endstop_align_zero', False)
         # Determine endstop accuracy
+        stepper_config = config.getsection(self.name)
+        self.step_dist = step_dist = stepper_config.getfloat('step_distance')
         endstop_accuracy = config.getfloat('endstop_accuracy', None, above=0.)
         if endstop_accuracy is None:
             self.endstop_accuracy = self.phases//2 - 1
@@ -44,8 +57,15 @@ class EndstopPhase:
         full_step = microsteps * self.step_dist
         return int(pos / full_step + .5) * full_step + phase_offset
     def get_homed_offset(self, stepper):
-        pos = stepper.get_mcu_position()
-        phase = pos % self.phases
+        if self.get_phase is not None:
+            try:
+                phase = self.get_phase()
+            except Exception as e:
+                msg = "Unable to get stepper %s phase: %s" % (self.name, str(e))
+                logging.exception(msg)
+                raise homing.EndstopError(msg)
+        else:
+            phase = stepper.get_mcu_position() % self.phases
         if self.endstop_phase is None:
             logging.info("Setting %s endstop phase to %d", self.name, phase)
             self.endstop_phase = phase

klippy/extras/tmc2130.py

@@ -137,6 +137,10 @@ class TMC2130:
         data = [(reg | 0x80) & 0xff, (val >> 24) & 0xff, (val >> 16) & 0xff,
                 (val >> 8) & 0xff, val & 0xff]
         self.spi_send_cmd.send([self.oid, data])
+    def get_microsteps(self):
+        return 256 >> self.mres
+    def get_phase(self):
+        return (self.get_register("MSCNT") & 0x3ff) >> self.mres
     cmd_DUMP_TMC_help = "Read and display TMC stepper driver registers"
     def cmd_DUMP_TMC(self, params):
         self.printer.lookup_object('toolhead').get_last_move_time()

klippy/extras/tmc2208.py

@@ -219,6 +219,10 @@ class TMC2208:
                 return
         raise self.printer.config_error(
             "Unable to write tmc2208 '%s' register %s" % (self.name, reg_name))
+    def get_microsteps(self):
+        return 256 >> self.mres
+    def get_phase(self):
+        return (self.get_register("MSCNT") & 0x3ff) >> self.mres
     cmd_DUMP_TMC_help = "Read and display TMC stepper driver registers"
     def cmd_DUMP_TMC(self, params):
         self.printer.lookup_object('toolhead').get_last_move_time()