manual_stepper: Implement "drip moves" for manual stepper STOP_ON_ENDSTOP

Currently, `MANUAL_STEPPER STOP_ON_ENDSTOP=1` type commands will move
until hitting the endstop, but it will still always consume the total
amount of move time.  That is, following moves can't be started until
the total possible time of the homing move is completed.

Implement "drip moves" so that the code only schedules the movement in
small segments.  This allows following movements to be scheduled
without a significant delay.

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

3 files changed, 27 insertions, 6 deletions

diff --git a/docs/Config_Changes.md b/docs/Config_Changes.md
index 47fa4cce..3059eec5 100644
--- a/docs/Config_Changes.md
+++ b/docs/Config_Changes.md
@@ -8,6 +8,11 @@ All dates in this document are approximate.
 
 ## Changes
 
+20250418: The manual_stepper `STOP_ON_ENDSTOP` feature may now take
+less time to complete. Previously, the command would wait the entire
+time the move could possibly take even if the endstop triggered
+earlier. Now, the command finishes shortly after the endstop trigger.
+
 20250417: SPI devices using "software SPI" are now rate limited.
 Previously, the `spi_speed` in the config was ignored and the
 transmission speed was only limited by the processing speed of the
diff --git a/klippy/extras/manual_stepper.py b/klippy/extras/manual_stepper.py
index 9f21cc8d..1465590d 100644
--- a/klippy/extras/manual_stepper.py
+++ b/klippy/extras/manual_stepper.py
@@ -55,17 +55,20 @@ class ManualStepper:
         self.sync_print_time()
     def do_set_position(self, setpos):
         self.rail.set_position([setpos, 0., 0.])
-    def do_move(self, movepos, speed, accel, sync=True):
-        self.sync_print_time()
+    def _submit_move(self, movetime, movepos, speed, accel):
         cp = self.rail.get_commanded_position()
         dist = movepos - cp
         axis_r, accel_t, cruise_t, cruise_v = force_move.calc_move_time(
             dist, speed, accel)
-        self.trapq_append(self.trapq, self.next_cmd_time,
+        self.trapq_append(self.trapq, movetime,
                           accel_t, cruise_t, accel_t,
                           cp, 0., 0., axis_r, 0., 0.,
                           0., cruise_v, accel)
-        self.next_cmd_time = self.next_cmd_time + accel_t + cruise_t + accel_t
+        return movetime + accel_t + cruise_t + accel_t
+    def do_move(self, movepos, speed, accel, sync=True):
+        self.sync_print_time()
+        self.next_cmd_time = self._submit_move(self.next_cmd_time, movepos,
+                                               speed, accel)
         self.rail.generate_steps(self.next_cmd_time)
         self.trapq_finalize_moves(self.trapq, self.next_cmd_time + 99999.9,
                                   self.next_cmd_time + 99999.9)
@@ -117,7 +120,18 @@ class ManualStepper:
     def dwell(self, delay):
         self.next_cmd_time += max(0., delay)
     def drip_move(self, newpos, speed, drip_completion):
-        self.do_move(newpos[0], speed, self.homing_accel)
+        # Submit move to trapq
+        self.sync_print_time()
+        maxtime = self._submit_move(self.next_cmd_time, newpos[0],
+                                    speed, self.homing_accel)
+        # Drip updates to motors
+        toolhead = self.printer.lookup_object('toolhead')
+        toolhead.drip_update_time(maxtime, drip_completion, self.steppers)
+        # Clear trapq of any remaining parts of movement
+        reactor = self.printer.get_reactor()
+        self.trapq_finalize_moves(self.trapq, reactor.NEVER, 0)
+        self.rail.set_position([newpos[0], 0., 0.])
+        self.sync_print_time()
     def get_kinematics(self):
         return self
     def get_steppers(self):
diff --git a/klippy/toolhead.py b/klippy/toolhead.py
index f7d7ef7e..806da7bf 100644
--- a/klippy/toolhead.py
+++ b/klippy/toolhead.py
@@ -503,7 +503,7 @@ class ToolHead:
     def get_extruder(self):
         return self.extruder
     # Homing "drip move" handling
-    def drip_update_time(self, next_print_time, drip_completion):
+    def drip_update_time(self, next_print_time, drip_completion, addstepper=()):
         # Transition from "NeedPrime"/"Priming"/main state to "Drip" state
         self.special_queuing_state = "Drip"
         self.need_check_pause = self.reactor.NEVER
@@ -526,6 +526,8 @@ class ToolHead:
             npt = min(self.print_time + DRIP_SEGMENT_TIME, next_print_time)
             self.note_mcu_movequeue_activity(npt + self.kin_flush_delay,
                                              set_step_gen_time=True)
+            for stepper in addstepper:
+                stepper.generate_steps(npt)
             self._advance_move_time(npt)
         # Exit "Drip" state
         self.reactor.update_timer(self.flush_timer, self.reactor.NOW)