PWAY 16-port SH1601A Driver (#67)

* pway 16-port SH1601A driver

Minimum viable driver.

* Update to pWay 16-port driver

* Rename kvmd/pway.py to plugins/ugpio/pway.py

Fixed file mods

* Delete pway.py

* Update pway.py

Fixed file changes to only one...

* fixed spaces on line 181

1 files changed, 200 insertions, 0 deletions

diff --git a/kvmd/plugins/ugpio/pway.py b/kvmd/plugins/ugpio/pway.py
new file mode 100644
index 00000000..1c5a71da
--- /dev/null
+++ b/kvmd/plugins/ugpio/pway.py
@@ -0,0 +1,200 @@
+# ========================================================================== #
+#                                                                            #
+#    KVMD - The main Pi-KVM daemon.                                          #
+#                                                                            #
+#                                                                            #
+#    Copyright (C) 2018-2021  Maxim Devaev <[email protected]>               #
+#                                                                            #
+#    Modified by SppokHCK September 2021 <Find me on Discord spook#8911>     #
+#                                                                            #
+#    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 re
+import multiprocessing
+import functools
+import errno
+import time
+
+from typing import Tuple
+from typing import Dict
+from typing import Optional
+
+import serial
+
+from ...logging import get_logger
+
+from ... import aiotools
+from ... import aiomulti
+from ... import aioproc
+
+from ...yamlconf import Option
+
+from ...validators.basic import valid_number
+from ...validators.basic import valid_float_f01
+from ...validators.os import valid_abs_path
+from ...validators.hw import valid_tty_speed
+
+from . import GpioDriverOfflineError
+from . import BaseUserGpioDriver
+
+
+# =====
+class Plugin(BaseUserGpioDriver):  # pylint: disable=too-many-instance-attributes
+    def __init__(
+        self,
+        instance_name: str,
+        notifier: aiotools.AioNotifier,
+
+        device_path: str,
+        speed: int,
+        read_timeout: float,
+        protocol: int,
+    ) -> None:
+
+        super().__init__(instance_name, notifier)
+
+        self.__device_path = device_path
+        self.__speed = speed
+        self.__read_timeout = read_timeout
+        self.__protocol = protocol
+
+        self.__ctl_queue: "multiprocessing.Queue[int]" = multiprocessing.Queue()
+        self.__channel_queue: "multiprocessing.Queue[Optional[int]]" = multiprocessing.Queue()
+        self.__channel: Optional[int] = -1
+
+        self.__proc: Optional[multiprocessing.Process] = None
+        self.__stop_event = multiprocessing.Event()
+
+    @classmethod
+    def get_plugin_options(cls) -> Dict:
+        return {
+            "device":       Option("",     type=valid_abs_path, unpack_as="device_path"),
+            "speed":        Option(19200, type=valid_tty_speed),
+            # speed for pWAY 16-Port 19200 8n1.
+            "read_timeout": Option(2.0,    type=valid_float_f01),
+            "protocol":     Option(1,      type=functools.partial(valid_number, min=1, max=2)),
+        }
+
+    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:
+        assert self.__proc is None
+        self.__proc = multiprocessing.Process(target=self.__serial_worker, daemon=True)
+        self.__proc.start()
+
+    async def run(self) -> None:
+        while True:
+            (got, channel) = await aiomulti.queue_get_last(self.__channel_queue, 1)
+            if got and self.__channel != channel:
+                self.__channel = channel
+                await self._notifier.notify()
+
+    async def cleanup(self) -> None:
+        if self.__proc is not None:
+            if self.__proc.is_alive():
+                get_logger(0).info("Stopping %s daemon ...", self)
+                self.__stop_event.set()
+            if self.__proc.exitcode is not None:
+                self.__proc.join()
+
+    async def read(self, pin: int) -> bool:
+        if not self.__is_online():
+            raise GpioDriverOfflineError(self)
+        return (self.__channel == pin)
+
+    async def write(self, pin: int, state: bool) -> None:
+        if not self.__is_online():
+            raise GpioDriverOfflineError(self)
+        if state and (0 <= pin <= 16):
+            self.__ctl_queue.put_nowait(pin)
+
+    # =====
+
+    def __is_online(self) -> bool:
+        return (
+            self.__proc is not None
+            and self.__proc.is_alive()
+            and self.__channel is not None
+        )
+
+    def __serial_worker(self) -> None:
+        logger = aioproc.settle(str(self), f"gpio-pway-{self._instance_name}")
+        while not self.__stop_event.is_set():
+            try:
+                with self.__get_serial() as tty:
+                    data = b""
+                    self.__channel_queue.put_nowait(-1)
+
+                    # Switch and then recieve the state.
+                    # FIXME: Get actual state without modifying the current.
+                    # I'm lazy and like the idea of the KVM resetting to port 1 on reboot of the PiKVM.
+                    self.__send_channel(tty, 0)
+
+                    while not self.__stop_event.is_set():
+                        (channel, data) = self.__recv_channel(tty, data)
+                        if channel is not None:
+                            self.__channel_queue.put_nowait(channel)
+
+                        (got, channel) = aiomulti.queue_get_last_sync(self.__ctl_queue, 0.1)  # type: ignore
+                        if got:
+                            assert channel is not None
+                            self.__send_channel(tty, channel)
+
+            except Exception as err:
+                self.__channel_queue.put_nowait(None)
+                if isinstance(err, serial.SerialException) and err.errno == errno.ENOENT:  # pylint: disable=no-member
+                    logger.error("Missing %s serial device: %s", self, self.__device_path)
+                else:
+                    logger.exception("Unexpected %s error", self)
+                time.sleep(1)
+
+    def __get_serial(self) -> serial.Serial:
+        return serial.Serial(self.__device_path, self.__speed, timeout=self.__read_timeout)
+
+    def __recv_channel(self, tty: serial.Serial, data: bytes) -> Tuple[Optional[int], bytes]:
+        channel: Optional[int] = None
+        if tty.in_waiting:
+            data += tty.read_all()
+            # When you switch ports you see something like "VGA_SWITCH_CONTROL=[0-15]" for ports 1-16
+            found = re.findall(b"VGA_SWITCH_CONTROL=[0-9]*", data)
+            if found:
+            	   channel = int(found[0].decode().split('=')[1]) + 1
+            data = data[-8:]
+        return (channel, data)
+
+    def __send_channel(self, tty: serial.Serial, channel: int) -> None:
+        # Set a channel by sending PS [1-16]
+        cmd = (b"PS")
+        if channel == 0:
+            # when it initializes this will push us to port 1 and set us back to defaults.
+            tty.write(b"%s\r" % (cmd))
+            tty.flush()
+        else:
+        	# Basically send `PS [1-16]` that switches the port
+            tty.write(b"%s %d\r" % (cmd, channel))
+            tty.flush()
+
+    def __str__(self) -> str:
+        return f"pway({self._instance_name})"
+
+    __repr__ = __str__