otgbind pseudo-gpio plugin

kvmd/apps/__init__.py

@@ -409,9 +409,10 @@ def _get_config_scheme() -> Dict:
             "udc":        Option("",     type=valid_stripped_string),
             "init_delay": Option(3.0,    type=valid_float_f01),
 
+            "user": Option("kvmd", type=valid_user),
+
             "devices": {
                 "msd": {
-                    "user": Option("kvmd", type=valid_user),
                     "default": {
                         "stall":     Option(False, type=valid_bool),
                         "cdrom":     Option(True,  type=valid_bool),

kvmd/apps/kvmd/__init__.py

@@ -81,7 +81,7 @@ def main(argv: Optional[List[str]]=None) -> None:
         info_manager=InfoManager(global_config),
         log_reader=LogReader(),
         wol=WakeOnLan(**config.wol._unpack()),
-        user_gpio=UserGpio(config.gpio),
+        user_gpio=UserGpio(config.gpio, global_config.otg.udc),
 
         hid=hid,
         atx=get_atx_class(config.atx.type)(**config.atx._unpack(ignore=["type"])),

kvmd/apps/kvmd/ugpio.py

@@ -231,7 +231,7 @@ class _GpioOutput:  # pylint: disable=too-many-instance-attributes
 
 # =====
 class UserGpio:
-    def __init__(self, config: Section) -> None:
+    def __init__(self, config: Section, udc: str) -> None:
         self.__view = config.view
 
         self.__notifier = aiotools.AioNotifier()
@@ -241,6 +241,7 @@ class UserGpio:
                 instance_name=driver,
                 notifier=self.__notifier,
                 **drv_config._unpack(ignore=["instance_name", "notifier", "type"]),
+                **({"udc": udc} if drv_config.type == "otgbind" else {}),  # Hack
             )
             for (driver, drv_config) in tools.sorted_kvs(config.drivers)
         }

kvmd/apps/otg/__init__.py

@@ -210,7 +210,7 @@ def _cmd_start(config: Section) -> None:
 
     if config.kvmd.msd.type == "otg":
         logger.info("===== Required MSD =====")
-        _create_msd(gadget_path, config_path, 0, config.otg.devices.msd.user, **config.otg.devices.msd.default._unpack())
+        _create_msd(gadget_path, config_path, 0, config.otg.user, **config.otg.devices.msd.default._unpack())
         if config.otg.devices.drives.enabled:
             logger.info("===== Required MSD extra drives: %d =====", config.otg.devices.drives.count)
             for instance in range(config.otg.devices.drives.count):
@@ -222,6 +222,11 @@ def _cmd_start(config: Section) -> None:
     _write(join(gadget_path, "UDC"), udc)
     time.sleep(config.otg.init_delay)
 
+    logger.info("Setting DWC2 bind permissions ...")
+    driver_path = f"{env.SYSFS_PREFIX}/sys/bus/platform/drivers/dwc2"
+    _chown(join(driver_path, "bind"), config.otg.user)
+    _chown(join(driver_path, "unbind"), config.otg.user)
+
     logger.info("Ready to work")
 
 

kvmd/plugins/ugpio/otgbind.py

@@ -0,0 +1,119 @@
+# ========================================================================== #
+#                                                                            #
+#    KVMD - The main Pi-KVM daemon.                                          #
+#                                                                            #
+#    Copyright (C) 2018  Maxim Devaev <mdevaev@gmail.com>                    #
+#                                                                            #
+#    This program is free software: you can redistribute it and/or modify    #
+#    it under the terms of the GNU General Public License as published by    #
+#    the Free Software Foundation, either version 3 of the License, or       #
+#    (at your option) any later version.                                     #
+#                                                                            #
+#    This program is distributed in the hope that it will be useful,         #
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of          #
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           #
+#    GNU General Public License for more details.                            #
+#                                                                            #
+#    You should have received a copy of the GNU General Public License       #
+#    along with this program.  If not, see <https://www.gnu.org/licenses/>.  #
+#                                                                            #
+# ========================================================================== #
+
+
+import os
+import asyncio
+
+from typing import Optional
+
+from ...logging import get_logger
+
+from ...inotify import InotifyMask
+from ...inotify import Inotify
+
+from ... import env
+from ... import aiotools
+
+from . import BaseUserGpioDriver
+
+
+# =====
+class Plugin(BaseUserGpioDriver):
+    def __init__(
+        self,
+        instance_name: str,
+        notifier: aiotools.AioNotifier,
+
+        udc: str,  # XXX: Not from options, see /kvmd/apps/kvmd/__init__.py for details
+    ) -> None:
+
+        super().__init__(instance_name, notifier)
+
+        self.__udc = udc
+
+    def register_input(self, pin: int, debounce: float) -> None:
+        _ = pin
+        _ = debounce
+
+    def register_output(self, pin: int, initial: Optional[bool]) -> None:
+        _ = pin
+        _ = initial
+
+    def prepare(self) -> None:
+        candidates = sorted(os.listdir(f"{env.SYSFS_PREFIX}/sys/class/udc"))
+        if not self.__udc:
+            if len(candidates) == 0:
+                raise RuntimeError("Can't find any UDC")
+            self.__udc = candidates[0]
+        elif self.__udc not in candidates:
+            raise RuntimeError(f"Can't find selected UDC: {self.__udc}")
+        get_logger().info("Using UDC %s", self.__udc)
+
+    async def run(self) -> None:
+        logger = get_logger(0)
+        while True:
+            try:
+                while True:
+                    await self._notifier.notify()
+                    if os.path.isdir(self.__get_driver_path()):
+                        break
+                    await asyncio.sleep(5)
+
+                with Inotify() as inotify:
+                    inotify.watch(self.__get_driver_path(), InotifyMask.ALL_MODIFY_EVENTS)
+                    await self._notifier.notify()
+                    while True:
+                        need_restart = False
+                        need_notify = False
+                        for event in (await inotify.get_series(timeout=1)):
+                            need_notify = True
+                            if event.mask & (InotifyMask.DELETE_SELF | InotifyMask.MOVE_SELF | InotifyMask.UNMOUNT):
+                                logger.warning("Got fatal inotify event: %s; reinitializing OTG-bind ...", event)
+                                need_restart = True
+                                break
+                        if need_restart:
+                            break
+                        if need_notify:
+                            await self._notifier.notify()
+            except Exception:
+                logger.exception("Unexpected OTG-bind watcher error")
+
+    def cleanup(self) -> None:
+        pass
+
+    def read(self, pin: int) -> bool:
+        _ = pin
+        return os.path.islink(self.__get_driver_path(self.__udc))
+
+    def write(self, pin: int, state: bool) -> None:
+        _ = pin
+        with open(self.__get_driver_path("bind" if state else "unbind"), "w") as ctl_file:
+            ctl_file.write(f"{self.__udc}\n")
+
+    def __get_driver_path(self, name: str="") -> str:
+        path = f"{env.SYSFS_PREFIX}/sys/bus/platform/drivers/dwc2"
+        return (os.path.join(path, name) if name else path)
+
+    def __str__(self) -> str:
+        return f"GPIO({self._instance_name})"
+
+    __repr__ = __str__