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venv/lib/python3.11/site-packages/gpiozero/pins/local.py

@@ -0,0 +1,214 @@
+# vim: set fileencoding=utf-8:
+#
+# GPIO Zero: a library for controlling the Raspberry Pi's GPIO pins
+#
+# Copyright (c) 2016-2023 Dave Jones <dave@waveform.org.uk>
+# Copyright (c) 2020 Fangchen Li <fangchen.li@outlook.com>
+# Copyright (c) 2016 Andrew Scheller <github@loowis.durge.org>
+#
+# SPDX-License-Identifier: BSD-3-Clause
+
+import io
+import errno
+import struct
+from collections import defaultdict
+from threading import Lock
+from time import monotonic
+
+try:
+    from spidev import SpiDev
+except ImportError:
+    SpiDev = None
+
+from . import SPI
+from .pi import PiFactory, PiPin, SPI_HARDWARE_PINS, spi_port_device
+from .spi import SPISoftware
+from ..devices import Device
+from ..mixins import SharedMixin
+from ..output_devices import OutputDevice
+from ..exc import DeviceClosed, PinUnknownPi, SPIInvalidClockMode
+
+
+def get_pi_revision():
+    revision = None
+    try:
+        with io.open('/proc/device-tree/system/linux,revision', 'rb') as f:
+            revision = hex(struct.unpack('>L', f.read(4))[0])[2:]
+    except IOError as e:
+        if e.errno != errno.ENOENT:
+            raise e
+        with io.open('/proc/cpuinfo', 'r') as f:
+            for line in f:
+                if line.startswith('Revision'):
+                    revision = line.split(':')[1].strip().lower()
+    if revision is not None:
+        overvolted = revision.startswith('100')
+        if overvolted:
+            revision = revision[-4:]
+        return int(revision, base=16)
+    raise PinUnknownPi(
+        'unable to locate Pi revision in /proc/device-tree or /proc/cpuinfo')
+
+
+class LocalPiFactory(PiFactory):
+    """
+    Extends :class:`~gpiozero.pins.pi.PiFactory`. Abstract base class
+    representing pins attached locally to a Pi. This forms the base class for
+    local-only pin interfaces (:class:`~gpiozero.pins.rpigpio.RPiGPIOPin`,
+    :class:`~gpiozero.pins.lgpio.LGPIOPin`, and
+    :class:`~gpiozero.pins.native.NativePin`).
+    """
+    pins = {}
+    _reservations = defaultdict(list)
+    _res_lock = Lock()
+
+    def __init__(self):
+        super().__init__()
+        # Override the reservations and pins dict to be this class' attributes.
+        # This is a bit of a dirty hack, but ensures that anyone evil enough to
+        # mix pin implementations doesn't try and control the same pin with
+        # different backends
+        self.pins = LocalPiFactory.pins
+        self._reservations = LocalPiFactory._reservations
+        self._res_lock = LocalPiFactory._res_lock
+
+    def _get_revision(self):
+        return get_pi_revision()
+
+    def _get_spi_class(self, shared, hardware):
+        return {
+            (False, True):  LocalPiHardwareSPI,
+            (True,  True):  LocalPiHardwareSPIShared,
+            (False, False): LocalPiSoftwareSPI,
+            (True,  False): LocalPiSoftwareSPIShared,
+            }[shared, hardware]
+
+    @staticmethod
+    def ticks():
+        return monotonic()
+
+    @staticmethod
+    def ticks_diff(later, earlier):
+        return later - earlier
+
+
+class LocalPiPin(PiPin):
+    """
+    Extends :class:`~gpiozero.pins.pi.PiPin`. Abstract base class representing
+    a multi-function GPIO pin attached to the local Raspberry Pi.
+    """
+    def _call_when_changed(self, ticks=None, state=None):
+        """
+        Overridden to provide default ticks from the local Pi factory.
+
+        .. warning::
+
+            The local pin factory uses a seconds-based monotonic value for
+            its ticks but you *must not* rely upon this behaviour. Ticks are
+            an opaque value that should only be compared with the associated
+            :meth:`Factory.ticks_diff` method.
+        """
+        super()._call_when_changed(
+            self._factory.ticks() if ticks is None else ticks,
+            self.state if state is None else state)
+
+
+class LocalPiHardwareSPI(SPI):
+    def __init__(self, clock_pin, mosi_pin, miso_pin, select_pin, pin_factory):
+        self._port, self._device = spi_port_device(
+            clock_pin, mosi_pin, miso_pin, select_pin)
+        self._bus = None
+        if SpiDev is None:
+            raise ImportError('failed to import spidev')
+        super().__init__(pin_factory=pin_factory)
+        to_reserve = {clock_pin, select_pin}
+        if mosi_pin is not None:
+            to_reserve.add(mosi_pin)
+        if miso_pin is not None:
+            to_reserve.add(miso_pin)
+        self.pin_factory.reserve_pins(self, *to_reserve)
+        self._bus = SpiDev()
+        self._bus.open(self._port, self._device)
+        self._bus.max_speed_hz = 500000
+
+    def _conflicts_with(self, other):
+        if isinstance(other, LocalPiHardwareSPI):
+            return (
+                (self._port == other._port) and
+                (self._device == other._device))
+        else:
+            return True
+
+    def close(self):
+        if self._bus is not None:
+            self._bus.close()
+        self._bus = None
+        self.pin_factory.release_all(self)
+        super().close()
+
+    @property
+    def closed(self):
+        return self._bus is None
+
+    def __repr__(self):
+        try:
+            self._check_open()
+            return 'SPI(port=%d, device=%d)' % (self._port, self._device)
+        except DeviceClosed:
+            return 'SPI(closed)'
+
+    def transfer(self, data):
+        """
+        Writes data (a list of integer words where each word is assumed to have
+        :attr:`bits_per_word` bits or less) to the SPI interface, and reads an
+        equivalent number of words, returning them as a list of integers.
+        """
+        return self._bus.xfer2(data)
+
+    def _get_clock_mode(self):
+        return self._bus.mode
+
+    def _set_clock_mode(self, value):
+        self._bus.mode = value
+
+    def _get_lsb_first(self):
+        return self._bus.lsbfirst
+
+    def _set_lsb_first(self, value):
+        self._bus.lsbfirst = bool(value)
+
+    def _get_select_high(self):
+        return self._bus.cshigh
+
+    def _set_select_high(self, value):
+        self._bus.cshigh = bool(value)
+
+    def _get_bits_per_word(self):
+        return self._bus.bits_per_word
+
+    def _set_bits_per_word(self, value):
+        self._bus.bits_per_word = value
+
+    def _get_rate(self):
+        return self._bus.max_speed_hz
+
+    def _set_rate(self, value):
+        self._bus.max_speed_hz = int(value)
+
+
+class LocalPiSoftwareSPI(SPISoftware):
+    pass
+
+
+class LocalPiHardwareSPIShared(SharedMixin, LocalPiHardwareSPI):
+    @classmethod
+    def _shared_key(cls, clock_pin, mosi_pin, miso_pin, select_pin,
+                    pin_factory):
+        return (clock_pin, select_pin)
+
+
+class LocalPiSoftwareSPIShared(SharedMixin, LocalPiSoftwareSPI):
+    @classmethod
+    def _shared_key(cls, clock_pin, mosi_pin, miso_pin, select_pin,
+                    pin_factory):
+        return (clock_pin, select_pin)