# SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries # # SPDX-License-Identifier: MIT """A Pin class for use with libgpiod.""" try: import gpiod except ImportError: raise ImportError( "libgpiod Python bindings not found, please install and try again! See " "https://github.com/adafruit/Raspberry-Pi-Installer-Scripts/blob/master/libgpiod.sh" ) from ImportError # pylint: disable=too-many-branches,too-many-statements class Pin: """Pins dont exist in CPython so...lets make our own!""" IN = 0 OUT = 1 LOW = 0 HIGH = 1 PULL_NONE = 0 PULL_UP = 1 PULL_DOWN = 2 _CONSUMER = "adafruit_blinka" id = None _value = LOW _mode = IN def __init__(self, pin_id): self.id = pin_id if isinstance(pin_id, tuple): self._num = int(pin_id[1]) if hasattr(gpiod, "Chip"): self._chip = gpiod.Chip(str(pin_id[0]), gpiod.Chip.OPEN_BY_NUMBER) else: self._chip = gpiod.chip(str(pin_id[0]), gpiod.chip.OPEN_BY_NUMBER) else: self._num = int(pin_id) if hasattr(gpiod, "Chip"): self._chip = gpiod.Chip("gpiochip0", gpiod.Chip.OPEN_BY_NAME) else: self._chip = gpiod.chip("gpiochip0", gpiod.chip.OPEN_BY_NAME) self._line = None def __repr__(self): return str(self.id) def __eq__(self, other): return self.id == other def init(self, mode=IN, pull=None): """Initialize the Pin""" if not self._line: self._line = self._chip.get_line(int(self._num)) # print("init line: ", self.id, self._line) if mode is not None: if mode == self.IN: flags = 0 self._line.release() if pull is not None: if pull == self.PULL_UP: if hasattr(gpiod, "line") and hasattr( gpiod.line, "BIAS_PULL_UP" ): config = gpiod.line_request() config.consumer = self._CONSUMER config.request_type = gpiod.line.BIAS_PULL_UP self._line.request(config) else: self._line.request( consumer=self._CONSUMER, type=gpiod.LINE_REQ_DIR_IN, flags=flags, ) raise NotImplementedError( "Internal pullups not supported in this version of libgpiod, " "use physical resistor instead!" ) elif pull == self.PULL_DOWN: if hasattr(gpiod, "line") and hasattr( gpiod.line, "BIAS_PULL_DOWN" ): config = gpiod.line_request() config.consumer = self._CONSUMER config.request_type = gpiod.line.BIAS_PULL_DOWN self._line.request(config) else: raise NotImplementedError( "Internal pulldowns not supported in this version of libgpiod, " "use physical resistor instead!" ) elif pull == self.PULL_NONE: if hasattr(gpiod, "line") and hasattr( gpiod.line, "BIAS_DISABLE" ): config = gpiod.line_request() config.consumer = self._CONSUMER config.request_type = gpiod.line.BIAS_DISABLE self._line.request(config) else: raise RuntimeError(f"Invalid pull for pin: {self.id}") self._mode = self.IN self._line.release() if hasattr(gpiod, "LINE_REQ_DIR_IN"): self._line.request( consumer=self._CONSUMER, type=gpiod.LINE_REQ_DIR_IN, flags=flags ) else: config = gpiod.line_request() config.consumer = self._CONSUMER config.request_type = gpiod.line_request.DIRECTION_INPUT self._line.request(config) elif mode == self.OUT: if pull is not None: raise RuntimeError("Cannot set pull resistor on output") self._mode = self.OUT self._line.release() if hasattr(gpiod, "LINE_REQ_DIR_OUT"): self._line.request( consumer=self._CONSUMER, type=gpiod.LINE_REQ_DIR_OUT ) else: config = gpiod.line_request() config.consumer = self._CONSUMER config.request_type = gpiod.line_request.DIRECTION_OUTPUT self._line.request(config) else: raise RuntimeError("Invalid mode for pin: %s" % self.id) def value(self, val=None): """Set or return the Pin Value""" if val is None: return self._line.get_value() if val in (self.LOW, self.HIGH): self._value = val self._line.set_value(val) return None raise RuntimeError("Invalid value for pin")