X-Git-Url: https://git.ayoreis.com/Adafruit_Blinka-hackapet.git/blobdiff_plain/cbaee77564e37047937a9c642d13f20b53821845..60fa43167c45c1ab162292dcf26d6dce9e001851:/src/adafruit_blinka/microcontroller/generic_linux/spi.py diff --git a/src/adafruit_blinka/microcontroller/generic_linux/spi.py b/src/adafruit_blinka/microcontroller/generic_linux/spi.py index a93c46b..6cce037 100755 --- a/src/adafruit_blinka/microcontroller/generic_linux/spi.py +++ b/src/adafruit_blinka/microcontroller/generic_linux/spi.py @@ -1,8 +1,14 @@ -import spidev -import time +# SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries +# +# SPDX-License-Identifier: MIT +"""Generic Linux SPI class using PureIO's SPI class""" +from Adafruit_PureIO import spi from adafruit_blinka.agnostic import detector + class SPI: + """SPI Class""" + MSB = 0 LSB = 1 CPHA = 1 @@ -13,96 +19,125 @@ class SPI: bits = 8 def __init__(self, portid): - self._port = portid - self._spi = spidev.SpiDev() + if isinstance(portid, tuple): + self._spi = spi.SPI(device=portid) + else: + self._spi = spi.SPI(device=(portid, 0)) + self.clock_pin = None + self.mosi_pin = None + self.miso_pin = None + self.chip = None - def init(self, baudrate=100000, polarity=0, phase=0, bits=8, - firstbit=MSB, sck=None, mosi=None, miso=None): + # pylint: disable=too-many-arguments,unused-argument + def init( + self, + baudrate=100000, + polarity=0, + phase=0, + bits=8, + firstbit=MSB, + sck=None, + mosi=None, + miso=None, + ): + """Initialize SPI""" mode = 0 if polarity: mode |= self.CPOL if phase: mode |= self.CPHA - - self.clock_pin = sck - self.mosi_pin = mosi - self.miso_pin = miso self.baudrate = baudrate self.mode = mode self.bits = bits self.chip = detector.chip + # Pins are not used + self.clock_pin = sck + self.mosi_pin = mosi + self.miso_pin = miso + + # pylint: enable=too-many-arguments,unused-argument + + # pylint: disable=unnecessary-pass def set_no_cs(self): - # Linux SPI driver for AM33XX chip in BeagleBone and PocketBeagle - # does not support setting SPI_NO_CS mode bit (issue #104) - if not self.chip.AM33XX and not self.chip.IMX8MX and not self.chip.SAMA5 \ - and not self.chip.APQ8016 and not self.chip.T210 and not self.chip.T186 \ - and not self.chip.T194 and not self.chip.SUN8I: - try: - self._spi.no_cs = True # this doesn't work but try anyways - except AttributeError: - pass + """Setting so that SPI doesn't automatically set the CS pin""" + # No kernel seems to support this, so we're just going to pass + pass + + # pylint: enable=unnecessary-pass @property def frequency(self): + """Return the current baudrate""" return self.baudrate def write(self, buf, start=0, end=None): - if not buf: + """Write data from the buffer to SPI""" + if buf is None or len(buf) < 1: return if end is None: end = len(buf) try: - self._spi.open(self._port, 0) + # self._spi.open(self._port, 0) self.set_no_cs() self._spi.max_speed_hz = self.baudrate self._spi.mode = self.mode self._spi.bits_per_word = self.bits - self._spi.writebytes2(buf[start:end]) - self._spi.close() - except FileNotFoundError as not_found: + self._spi.writebytes(buf[start:end]) + # self._spi.close() + except FileNotFoundError: print("Could not open SPI device - check if SPI is enabled in kernel!") raise def readinto(self, buf, start=0, end=None, write_value=0): - if not buf: + """Read data from SPI and into the buffer""" + if buf is None or len(buf) < 1: return if end is None: end = len(buf) try: - self._spi.open(self._port, 0) - self.set_no_cs() + # self._spi.open(self._port, 0) + # self.set_no_cs() self._spi.max_speed_hz = self.baudrate self._spi.mode = self.mode self._spi.bits_per_word = self.bits - data = self._spi.xfer([write_value]*(end-start)) - for i in range(end-start): # 'readinto' the given buffer - buf[start+i] = data[i] - self._spi.close() - except FileNotFoundError as not_found: + data = self._spi.transfer([write_value] * (end - start)) + for i in range(end - start): # 'readinto' the given buffer + buf[start + i] = data[i] + # self._spi.close() + except FileNotFoundError: print("Could not open SPI device - check if SPI is enabled in kernel!") raise - def write_readinto(self, buffer_out, buffer_in, out_start=0, - out_end=None, in_start=0, in_end=None): - if not buffer_out or not buffer_in: + # pylint: disable=too-many-arguments + def write_readinto( + self, buffer_out, buffer_in, out_start=0, out_end=None, in_start=0, in_end=None + ): + """Perform a half-duplex write from buffer_out and then + read data into buffer_in + """ + if buffer_out is None or buffer_in is None: + return + if len(buffer_out) < 1 or len(buffer_in) < 1: return if out_end is None: out_end = len(buffer_out) if in_end is None: in_end = len(buffer_in) if out_end - out_start != in_end - in_start: - raise RuntimeError('Buffer slices must be of equal length.') + raise RuntimeError("Buffer slices must be of equal length.") try: - self._spi.open(self._port, 0) - self.set_no_cs() + # self._spi.open(self._port, 0) + # self.set_no_cs() self._spi.max_speed_hz = self.baudrate self._spi.mode = self.mode self._spi.bits_per_word = self.bits - data = self._spi.xfer(list(buffer_out[out_start:out_end+1])) + data = self._spi.transfer(list(buffer_out[out_start : out_end + 1])) for i in range((in_end - in_start)): - buffer_in[i+in_start] = data[i] - self._spi.close() - except FileNotFoundError as not_found: + buffer_in[i + in_start] = data[i] + # self._spi.close() + except FileNotFoundError: print("Could not open SPI device - check if SPI is enabled in kernel!") raise + + # pylint: enable=too-many-arguments