mcu: Restart mcu by running executable on host

docs/Config_Reference.md

@@ -56,6 +56,14 @@ serial:
 #   sending a Klipper command to the micro-controller so that it can
 #   reset itself. The default is 'arduino' if the micro-controller
 #   communicates over a serial port, 'command' otherwise.
+#restart_command:
+#   This option takes path to executable or script that will be executed
+#   as firmware reset. If restart command is defined for given MCU,
+#   it will be sent prior to closing port and executing script.
+#   use this to poke some GPIO that leads to mcu reset pin
+#   or to force reload kernel drivers.
+#   Note that content and results of execution of such script are beyond
+#   scope of klipper software.
 ```
 
 ## [mcu my_extra_mcu]

klippy/mcu.py

@@ -3,7 +3,7 @@
 # Copyright (C) 2016-2021  Kevin O'Connor <[email protected]>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import sys, os, zlib, logging, math
+import sys, os, zlib, logging, math, subprocess
 import serialhdl, pins, chelper, clocksync
 
 class error(Exception):
@@ -436,6 +436,9 @@ def __init__(self, config, clocksync):
             rmethods = {m: m for m in restart_methods}
             self._restart_method = config.getchoice('restart_method',
                                                     rmethods, None)
+        self._restart_command= config.get('restart_command',None)
+        if self._restart_command!=None:
+            self._restart_method = 'host_command'
         self._reset_cmd = self._config_reset_cmd = None
         self._emergency_stop_cmd = None
         self._is_shutdown = self._is_timeout = False
@@ -585,7 +588,7 @@ def _log_info(self):
     def _connect(self):
         config_params = self._send_get_config()
         if not config_params['is_config']:
-            if self._restart_method == 'rpi_usb':
+            if self._restart_method in ['rpi_usb','host_command']:
                 # Only configure mcu after usb power reset
                 self._check_restart("full reset before config")
             # Not configured - send config and issue get_config again
@@ -621,7 +624,8 @@ def _mcu_identify(self):
             self._connect_file()
         else:
             resmeth = self._restart_method
-            if resmeth == 'rpi_usb' and not os.path.exists(self._serialport):
+            if resmeth in ['rpi_usb','host_command']
+                    and not os.path.exists(self._serialport):
                 # Try toggling usb power
                 self._check_restart("enable power")
             try:
@@ -774,9 +778,20 @@ def _restart_rpi_usb(self):
         chelper.run_hub_ctrl(0)
         self._reactor.pause(self._reactor.monotonic() + 2.)
         chelper.run_hub_ctrl(1)
+    def _restart_via_host_command(self):
+        logging.info("Attempting MCU '%s' reset via host command", self._name)
+        if self._reset_cmd is not None: #let mcu cleanup themself first
+            self._reset_cmd.send()
+            self._reactor.pause(self._reactor.monotonic() + 0.015)
+        self._disconnect()
+        logging.info(
+            subprocess.check_output([self._restart_command],
+                                    shell=True))
     def microcontroller_restart(self):
         if self._restart_method == 'rpi_usb':
             self._restart_rpi_usb()
+        elif self._restart_method == 'host_command':
+            self._restart_via_host_command()
         elif self._restart_method == 'command':
             self._restart_via_command()
         elif self._restart_method == 'cheetah':