-import spidev
-import time
+"""Generic Linux SPI class using PureIO's SPI class"""
+import Adafruit_PureIO.spi as spi
from adafruit_blinka.agnostic import detector
+
class SPI:
+ """SPI Class"""
+
MSB = 0
LSB = 1
CPHA = 1
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:
- 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):
+ """Write data from the buffer to SPI"""
if not buf:
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):
+ """Read data from SPI and into the buffer"""
if not buf:
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):
+ # 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 not buffer_out or not buffer_in:
return
if out_end is None:
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