2020-11-11 22:24:25 +03:00

156 lines
5.2 KiB
Python

# ========================================================================== #
# #
# 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 contextlib
import time
from typing import List
from typing import Dict
from typing import Generator
from typing import Any
import spidev
from ...logging import get_logger
from ...yamlconf import Option
from ...validators.basic import valid_int_f0
from ...validators.basic import valid_int_f1
from ...validators.basic import valid_float_f0
from ...validators.basic import valid_float_f01
from ._mcu import BasePhyConnection
from ._mcu import BasePhy
from ._mcu import BaseMcuHid
# =====
class _SpiPhyConnection(BasePhyConnection):
def __init__(
self,
spi: spidev.SpiDev,
read_timeout: float,
read_delay: float,
) -> None:
self.__spi = spi
self.__read_timeout = read_timeout
self.__read_delay = read_delay
self.__empty8 = b"\x00" * 8
self.__empty4 = b"\x00" * 4
def send(self, request: bytes) -> bytes:
assert len(request) == 8
deadline_ts = time.time() + self.__read_timeout
while time.time() < deadline_ts:
garbage = bytes(self.__spi.xfer(self.__empty8))
if garbage == self.__empty8:
break
else:
get_logger(0).error("SPI timeout reached while reading the a garbage")
return b""
self.__spi.xfer(request)
response: List[int] = []
deadline_ts = time.time() + self.__read_timeout
found = False
while time.time() < deadline_ts:
if not found:
time.sleep(self.__read_delay)
for byte in self.__spi.xfer(self.__empty4):
if not found:
if byte == 0:
continue
found = True
response.append(byte)
if len(response) >= 4:
break
if len(response) >= 4:
break
else:
get_logger(0).error("SPI timeout reached while responce waiting")
return b""
assert len(response) == 4
return bytes(response)
class _SpiPhy(BasePhy):
def __init__(
self,
bus: int,
chip: int,
max_freq: int,
read_timeout: float,
read_delay: float,
) -> None:
self.__bus = bus
self.__chip = chip
self.__max_freq = max_freq
self.__read_timeout = read_timeout
self.__read_delay = read_delay
def has_device(self) -> bool:
return os.path.exists(f"/dev/spidev{self.__bus}.{self.__chip}")
@contextlib.contextmanager
def connected(self) -> Generator[_SpiPhyConnection, None, None]: # type: ignore
with contextlib.closing(spidev.SpiDev(self.__bus, self.__chip)) as spi:
spi.mode = 0
spi.max_speed_hz = self.__max_freq
yield _SpiPhyConnection(spi, self.__read_timeout, self.__read_delay)
# =====
class Plugin(BaseMcuHid):
def __init__(
self,
bus: int,
chip: int,
max_freq: int,
read_timeout: float,
read_delay: float,
**kwargs: Any,
) -> None:
super().__init__(
phy=_SpiPhy(bus, chip, max_freq, read_timeout, read_delay),
**kwargs,
)
@classmethod
def get_plugin_options(cls) -> Dict:
return {
"bus": Option(0, type=valid_int_f0),
"chip": Option(0, type=valid_int_f0),
"max_freq": Option(1000000, type=valid_int_f1),
"read_timeout": Option(2.0, type=valid_float_f01),
"read_delay": Option(0.001, type=valid_float_f0),
**BaseMcuHid.get_plugin_options(),
}