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moved a bunch of garbage (things that have nothing to do in root) to _trash

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# SPDX-FileCopyrightText: 2020 Melissa LeBlanc-Williams for Adafruit Industries
#
# SPDX-License-Identifier: MIT

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# SPDX-FileCopyrightText: 2016 Tony DiCola for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""
`Adafruit_PureIO.smbus`
================================================================================
Pure python (i.e. no native extensions) access to Linux IO I2C interface that mimics the
Python SMBus API.
* Author(s): Tony DiCola, Lady Ada, Melissa LeBlanc-Williams
Implementation Notes
--------------------
**Software and Dependencies:**
* Linux and Python 3.5 or Higher
"""
from ctypes import c_uint8, c_uint16, c_uint32, cast, pointer, POINTER
from ctypes import create_string_buffer, Structure
from fcntl import ioctl
import struct
# pylint: disable=fixme
# I2C C API constants (from linux kernel headers)
I2C_M_TEN = 0x0010 # this is a ten bit chip address
I2C_M_RD = 0x0001 # read data, from slave to master
I2C_M_STOP = 0x8000 # if I2C_FUNC_PROTOCOL_MANGLING
I2C_M_NOSTART = 0x4000 # if I2C_FUNC_NOSTART
I2C_M_REV_DIR_ADDR = 0x2000 # if I2C_FUNC_PROTOCOL_MANGLING
I2C_M_IGNORE_NAK = 0x1000 # if I2C_FUNC_PROTOCOL_MANGLING
I2C_M_NO_RD_ACK = 0x0800 # if I2C_FUNC_PROTOCOL_MANGLING
I2C_M_RECV_LEN = 0x0400 # length will be first received byte
I2C_SLAVE = 0x0703 # Use this slave address
I2C_SLAVE_FORCE = 0x0706 # Use this slave address, even if
# is already in use by a driver!
I2C_TENBIT = 0x0704 # 0 for 7 bit addrs, != 0 for 10 bit
I2C_FUNCS = 0x0705 # Get the adapter functionality mask
I2C_RDWR = 0x0707 # Combined R/W transfer (one STOP only)
I2C_PEC = 0x0708 # != 0 to use PEC with SMBus
I2C_SMBUS = 0x0720 # SMBus transfer
# ctypes versions of I2C structs defined by kernel.
# Tone down pylint for the Python classes that mirror C structs.
# pylint: disable=invalid-name,too-few-public-methods
class i2c_msg(Structure):
"""Linux i2c_msg struct."""
_fields_ = [
("addr", c_uint16),
("flags", c_uint16),
("len", c_uint16),
("buf", POINTER(c_uint8)),
]
class i2c_rdwr_ioctl_data(Structure): # pylint: disable=invalid-name
"""Linux i2c data struct."""
_fields_ = [("msgs", POINTER(i2c_msg)), ("nmsgs", c_uint32)]
# pylint: enable=invalid-name,too-few-public-methods
# pylint: disable=attribute-defined-outside-init
def make_i2c_rdwr_data(messages):
"""Utility function to create and return an i2c_rdwr_ioctl_data structure
populated with a list of specified I2C messages. The messages parameter
should be a list of tuples which represent the individual I2C messages to
send in this transaction. Tuples should contain 4 elements: address value,
flags value, buffer length, ctypes c_uint8 pointer to buffer.
"""
# Create message array and populate with provided data.
msg_data_type = i2c_msg * len(messages)
msg_data = msg_data_type()
for i, message in enumerate(messages):
msg_data[i].addr = message[0] & 0x7F
msg_data[i].flags = message[1]
msg_data[i].len = message[2]
msg_data[i].buf = message[3]
# Now build the data structure.
data = i2c_rdwr_ioctl_data()
data.msgs = msg_data
data.nmsgs = len(messages)
return data
# pylint: enable=attribute-defined-outside-init
# Create an interface that mimics the Python SMBus API.
class SMBus:
"""I2C interface that mimics the Python SMBus API but is implemented with
pure Python calls to ioctl and direct /dev/i2c device access.
"""
def __init__(self, bus=None):
"""Create a new smbus instance. Bus is an optional parameter that
specifies the I2C bus number to use, for example 1 would use device
/dev/i2c-1. If bus is not specified then the open function should be
called to open the bus.
"""
self._device = None
if bus is not None:
self.open(bus)
def __del__(self):
"""Clean up any resources used by the SMBus instance."""
self.close()
def __enter__(self):
"""Context manager enter function."""
# Just return this object so it can be used in a with statement, like
# with SMBus(1) as bus:
# # do stuff!
return self
def __exit__(self, exc_type, exc_val, exc_tb):
"""Context manager exit function, ensures resources are cleaned up."""
self.close()
return False # Don't suppress exceptions.
def open(self, bus):
"""Open the smbus interface on the specified bus."""
# Close the device if it's already open.
if self._device is not None:
self.close()
# Try to open the file for the specified bus. Must turn off buffering
# or else Python 3 fails (see: https://bugs.python.org/issue20074)
# pylint: disable=consider-using-with
self._device = open(f"/dev/i2c-{bus}", "r+b", buffering=0)
# pylint: enable=consider-using-with
# TODO: Catch IOError and throw a better error message that describes
# what's wrong (i.e. I2C may not be enabled or the bus doesn't exist).
def close(self):
"""Close the smbus connection. You cannot make any other function
calls on the bus unless open is called!"""
if self._device is not None:
self._device.close()
self._device = None
def _select_device(self, addr):
"""Set the address of the device to communicate with on the I2C bus."""
ioctl(self._device.fileno(), I2C_SLAVE, addr & 0x7F)
def read_byte(self, addr):
"""Read a single byte from the specified device."""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
self._select_device(addr)
return ord(self._device.read(1))
def read_bytes(self, addr, number):
"""Read many bytes from the specified device."""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
self._select_device(addr)
return self._device.read(number)
def read_byte_data(self, addr, cmd):
"""Read a single byte from the specified cmd register of the device."""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Build ctypes values to marshall between ioctl and Python.
reg = c_uint8(cmd)
result = c_uint8()
# Build ioctl request.
request = make_i2c_rdwr_data(
[
(addr, 0, 1, pointer(reg)), # Write cmd register.
(addr, I2C_M_RD, 1, pointer(result)), # Read 1 byte as result.
]
)
# Make ioctl call and return result data.
ioctl(self._device.fileno(), I2C_RDWR, request)
return result.value
def read_word_data(self, addr, cmd):
"""Read a word (2 bytes) from the specified cmd register of the device.
Note that this will interpret data using the endianness of the processor
running Python (typically little endian)!
"""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Build ctypes values to marshall between ioctl and Python.
reg = c_uint8(cmd)
result = c_uint16()
# Build ioctl request.
request = make_i2c_rdwr_data(
[
(addr, 0, 1, pointer(reg)), # Write cmd register.
(
addr,
I2C_M_RD,
2,
cast(pointer(result), POINTER(c_uint8)),
), # Read word (2 bytes).
]
)
# Make ioctl call and return result data.
ioctl(self._device.fileno(), I2C_RDWR, request)
return result.value
def read_block_data(self, addr, cmd):
"""Perform a block read from the specified cmd register of the device.
The amount of data read is determined by the first byte send back by
the device. Data is returned as a bytearray.
"""
# TODO: Unfortunately this will require calling the low level I2C
# access ioctl to trigger a proper read_block_data. The amount of data
# returned isn't known until the device starts responding so an I2C_RDWR
# ioctl won't work.
raise NotImplementedError()
def read_i2c_block_data(self, addr, cmd, length=32):
"""Perform a read from the specified cmd register of device. Length number
of bytes (default of 32) will be read and returned as a bytearray.
"""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Build ctypes values to marshall between ioctl and Python.
# convert register into bytearray
if not isinstance(cmd, (bytes, bytearray)):
reg = cmd # backup
cmd = bytearray(1)
cmd[0] = reg
cmdstring = create_string_buffer(len(cmd))
for i, val in enumerate(cmd):
cmdstring[i] = val
result = create_string_buffer(length)
# Build ioctl request.
request = make_i2c_rdwr_data(
[
(
addr,
0,
len(cmd),
cast(cmdstring, POINTER(c_uint8)),
), # Write cmd register.
(addr, I2C_M_RD, length, cast(result, POINTER(c_uint8))), # Read data.
]
)
# Make ioctl call and return result data.
ioctl(self._device.fileno(), I2C_RDWR, request)
return bytearray(
result.raw
) # Use .raw instead of .value which will stop at a null byte!
def write_quick(self, addr):
"""Write a single byte to the specified device."""
# What a strange function, from the python-smbus source this appears to
# just write a single byte that initiates a write to the specified device
# address (but writes no data!). The functionality is duplicated below
# but the actual use case for this is unknown.
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Build ioctl request.
request = make_i2c_rdwr_data(
[
(addr, 0, 0, None),
]
) # Write with no data.
# Make ioctl call and return result data.
ioctl(self._device.fileno(), I2C_RDWR, request)
def write_byte(self, addr, val):
"""Write a single byte to the specified device."""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
self._select_device(addr)
data = bytearray(1)
data[0] = val & 0xFF
self._device.write(data)
def write_bytes(self, addr, buf):
"""Write many bytes to the specified device. buf is a bytearray"""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
self._select_device(addr)
self._device.write(buf)
def write_byte_data(self, addr, cmd, val):
"""Write a byte of data to the specified cmd register of the device."""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Construct a string of data to send with the command register and byte value.
data = bytearray(2)
data[0] = cmd & 0xFF
data[1] = val & 0xFF
# Send the data to the device.
self._select_device(addr)
self._device.write(data)
def write_word_data(self, addr, cmd, val):
"""Write a word (2 bytes) of data to the specified cmd register of the
device. Note that this will write the data in the endianness of the
processor running Python (typically little endian)!
"""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Construct a string of data to send with the command register and word value.
data = struct.pack("=BH", cmd & 0xFF, val & 0xFFFF)
# Send the data to the device.
self._select_device(addr)
self._device.write(data)
def write_block_data(self, addr, cmd, vals):
"""Write a block of data to the specified cmd register of the device.
The amount of data to write should be the first byte inside the vals
string/bytearray and that count of bytes of data to write should follow
it.
"""
# Just use the I2C block data write to write the provided values and
# their length as the first byte.
data = bytearray(len(vals) + 1)
data[0] = len(vals) & 0xFF
data[1:] = vals[0:]
self.write_i2c_block_data(addr, cmd, data)
def write_i2c_block_data(self, addr, cmd, vals):
"""Write a buffer of data to the specified cmd register of the device."""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Construct a string of data to send, including room for the command register.
data = bytearray(len(vals) + 1)
data[0] = cmd & 0xFF # Command register at the start.
data[1:] = vals[0:] # Copy in the block data (ugly but necessary to ensure
# the entire write happens in one transaction).
# Send the data to the device.
self._select_device(addr)
self._device.write(data)
def process_call(self, addr, cmd, val):
"""Perform a smbus process call by writing a word (2 byte) value to
the specified register of the device, and then reading a word of response
data (which is returned).
"""
assert (
self._device is not None
), "Bus must be opened before operations are made against it!"
# Build ctypes values to marshall between ioctl and Python.
data = create_string_buffer(struct.pack("=BH", cmd, val))
result = c_uint16()
# Build ioctl request.
request = make_i2c_rdwr_data(
[
(addr, 0, 3, cast(pointer(data), POINTER(c_uint8))), # Write data.
(
addr,
I2C_M_RD,
2,
cast(pointer(result), POINTER(c_uint8)),
), # Read word (2 bytes).
]
)
# Make ioctl call and return result data.
ioctl(self._device.fileno(), I2C_RDWR, request)
# Note the python-smbus code appears to have a rather serious bug and
# does not return the result value! This is fixed below by returning it.
return result.value

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# SPDX-FileCopyrightText: 2020 Melissa LeBlanc-Williams for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""
`Adafruit_PureIO.spi`
================================================================================
Pure python (i.e. no native extensions) access to Linux IO SPI interface that is
similar to the SpiDev API. Based heavily on https://github.com/tomstokes/python-spi/.
* Author(s): Tom Stokes, Melissa LeBlanc-Williams
Implementation Notes
--------------------
**Software and Dependencies:**
* Linux and Python 3.5 or Higher
"""
# imports
from ctypes import create_string_buffer, string_at, addressof
from fcntl import ioctl
import struct
import platform
import os.path
from os import environ
import array
__version__ = "1.1.11"
__repo__ = "https://github.com/adafruit/Adafruit_Python_PureIO.git"
# SPI C API constants (from linux kernel headers)
SPI_CPHA = 0x01
SPI_CPOL = 0x02
SPI_CS_HIGH = 0x04
SPI_LSB_FIRST = 0x08
SPI_THREE_WIRE = 0x10
SPI_LOOP = 0x20
SPI_NO_CS = 0x40
SPI_READY = 0x80
SPI_TX_DUAL = 0x100
SPI_TX_QUAD = 0x200
SPI_RX_DUAL = 0x400
SPI_RX_QUAD = 0x800
SPI_MODE_0 = 0
SPI_MODE_1 = SPI_CPHA
SPI_MODE_2 = SPI_CPOL
SPI_MODE_3 = SPI_CPHA | SPI_CPOL
SPI_DEFAULT_CHUNK_SIZE = 4096
def _ioc_encode(direction, number, structure):
"""
ioctl command encoding helper function
Calculates the appropriate spidev ioctl op argument given the direction,
command number, and argument structure in python's struct.pack format.
Returns a tuple of the calculated op and the struct.pack format
See Linux kernel source file /include/uapi/asm/ioctl.h
"""
ioc_magic = ord("k")
ioc_nrbits = 8
ioc_typebits = 8
if platform.machine() == "mips":
ioc_sizebits = 13
else:
ioc_sizebits = 14
ioc_nrshift = 0
ioc_typeshift = ioc_nrshift + ioc_nrbits
ioc_sizeshift = ioc_typeshift + ioc_typebits
ioc_dirshift = ioc_sizeshift + ioc_sizebits
size = struct.calcsize(structure)
operation = (
(direction << ioc_dirshift)
| (ioc_magic << ioc_typeshift)
| (number << ioc_nrshift)
| (size << ioc_sizeshift)
)
return direction, operation, structure
# pylint: disable=too-many-instance-attributes, too-many-branches
class SPI:
"""
This class is similar to SpiDev, but instead of opening and closing
for each call, it is set up on initialization making it fast.
"""
_IOC_TRANSFER_FORMAT = "QQIIHBBBBH"
if platform.machine() == "mips":
# Direction is 3 bits
_IOC_READ = 2
_IOC_WRITE = 4
else:
# Direction is 2 bits
_IOC_WRITE = 1
_IOC_READ = 2
# _IOC_MESSAGE is a special case, so we ony need the ioctl operation
_IOC_MESSAGE = _ioc_encode(_IOC_WRITE, 0, _IOC_TRANSFER_FORMAT)[1]
_IOC_RD_MODE = _ioc_encode(_IOC_READ, 1, "B")
_IOC_WR_MODE = _ioc_encode(_IOC_WRITE, 1, "B")
_IOC_RD_LSB_FIRST = _ioc_encode(_IOC_READ, 2, "B")
_IOC_WR_LSB_FIRST = _ioc_encode(_IOC_WRITE, 2, "B")
_IOC_RD_BITS_PER_WORD = _ioc_encode(_IOC_READ, 3, "B")
_IOC_WR_BITS_PER_WORD = _ioc_encode(_IOC_WRITE, 3, "B")
_IOC_RD_MAX_SPEED_HZ = _ioc_encode(_IOC_READ, 4, "I")
_IOC_WR_MAX_SPEED_HZ = _ioc_encode(_IOC_WRITE, 4, "I")
_IOC_RD_MODE32 = _ioc_encode(_IOC_READ, 5, "I")
_IOC_WR_MODE32 = _ioc_encode(_IOC_WRITE, 5, "I")
# pylint: disable=too-many-arguments
def __init__(
self,
device,
max_speed_hz=None,
bits_per_word=None,
phase=None,
polarity=None,
cs_high=None,
lsb_first=None,
three_wire=None,
loop=None,
no_cs=None,
ready=None,
):
"""
Create spidev interface object.
"""
if isinstance(device, tuple):
(bus, dev) = device
device = f"/dev/spidev{bus:d}.{dev:d}"
if not os.path.exists(device):
raise IOError(f"{device} does not exist")
self.handle = os.open(device, os.O_RDWR)
self.chunk_size = SPI_DEFAULT_CHUNK_SIZE
if environ.get("SPI_BUFSIZE") is not None:
try:
self.chunk_size = int(os.environ.get("SPI_BUFSIZE"))
except ValueError:
self.chunk_size = SPI_DEFAULT_CHUNK_SIZE
if max_speed_hz is not None:
self.max_speed_hz = max_speed_hz
if bits_per_word is not None:
self.bits_per_word = bits_per_word
if phase is not None:
self.phase = phase
if polarity is not None:
self.polarity = polarity
if cs_high is not None:
self.cs_high = cs_high
if lsb_first is not None:
self.lsb_first = lsb_first
if three_wire is not None:
self.three_wire = three_wire
if loop is not None:
self.loop = loop
if no_cs is not None:
self.no_cs = no_cs
if ready is not None:
self.ready = ready
# pylint: enable=too-many-arguments
def _ioctl(self, ioctl_data, data=None):
"""
ioctl helper function.
Performs an ioctl on self.handle. If the ioctl is an SPI read type
ioctl, returns the result value.
"""
(direction, ioctl_bytes, structure) = ioctl_data
if direction == SPI._IOC_READ:
arg = array.array(structure, [0])
ioctl(self.handle, ioctl_bytes, arg, True)
return arg[0]
arg = struct.pack("=" + structure, data)
ioctl(self.handle, ioctl_bytes, arg)
return None
def _get_mode_field(self, field):
"""Helper function to get specific spidev mode bits"""
return bool(self._ioctl(SPI._IOC_RD_MODE) & field)
def _set_mode_field(self, field, value):
"""Helper function to set a spidev mode bit"""
mode = self._ioctl(SPI._IOC_RD_MODE)
if value:
mode |= field
else:
mode &= ~field
self._ioctl(SPI._IOC_WR_MODE, mode)
@property
def phase(self):
"""SPI clock phase bit"""
return self._get_mode_field(SPI_CPHA)
@phase.setter
def phase(self, phase):
self._set_mode_field(SPI_CPHA, phase)
@property
def polarity(self):
"""SPI polarity bit"""
return self._get_mode_field(SPI_CPOL)
@polarity.setter
def polarity(self, polarity):
self._set_mode_field(SPI_CPOL, polarity)
@property
def cs_high(self):
"""SPI chip select active level"""
return self._get_mode_field(SPI_CS_HIGH)
@cs_high.setter
def cs_high(self, cs_high):
self._set_mode_field(SPI_CS_HIGH, cs_high)
@property
def lsb_first(self):
"""Bit order of SPI word transfers"""
return self._get_mode_field(SPI_LSB_FIRST)
@lsb_first.setter
def lsb_first(self, lsb_first):
self._set_mode_field(SPI_LSB_FIRST, lsb_first)
@property
def three_wire(self):
"""SPI 3-wire mode"""
return self._get_mode_field(SPI_THREE_WIRE)
@three_wire.setter
def three_wire(self, three_wire):
self._set_mode_field(SPI_THREE_WIRE, three_wire)
@property
def loop(self):
"""SPI loopback mode"""
return self._get_mode_field(SPI_LOOP)
@loop.setter
def loop(self, loop):
self._set_mode_field(SPI_LOOP, loop)
@property
def no_cs(self):
"""No chipselect. Single device on bus."""
return self._get_mode_field(SPI_NO_CS)
@no_cs.setter
def no_cs(self, no_cs):
self._set_mode_field(SPI_NO_CS, no_cs)
@property
def ready(self):
"""Slave pulls low to pause"""
return self._get_mode_field(SPI_READY)
@ready.setter
def ready(self, ready):
self._set_mode_field(SPI_READY, ready)
@property
def max_speed_hz(self):
"""Maximum SPI transfer speed in Hz.
Note that the controller cannot necessarily assign the requested
speed.
"""
return self._ioctl(SPI._IOC_RD_MAX_SPEED_HZ)
@max_speed_hz.setter
def max_speed_hz(self, max_speed_hz):
self._ioctl(SPI._IOC_WR_MAX_SPEED_HZ, max_speed_hz)
@property
def bits_per_word(self):
"""Number of bits per word of SPI transfer.
A value of 0 is equivalent to 8 bits per word
"""
return self._ioctl(SPI._IOC_RD_BITS_PER_WORD)
@bits_per_word.setter
def bits_per_word(self, bits_per_word):
self._ioctl(SPI._IOC_WR_BITS_PER_WORD, bits_per_word)
@property
def mode(self):
"""Mode that SPI is currently running in"""
return self._ioctl(SPI._IOC_RD_MODE)
@mode.setter
def mode(self, mode):
self._ioctl(SPI._IOC_WR_MODE, mode)
def writebytes(self, data, max_speed_hz=0, bits_per_word=0, delay=0):
"""Perform half-duplex SPI write."""
data = array.array("B", data).tobytes()
# length = len(data)
chunks = [
data[i : i + self.chunk_size] for i in range(0, len(data), self.chunk_size)
]
for chunk in chunks:
length = len(chunk)
transmit_buffer = create_string_buffer(chunk)
spi_ioc_transfer = struct.pack(
SPI._IOC_TRANSFER_FORMAT,
addressof(transmit_buffer),
0,
length,
max_speed_hz,
delay,
bits_per_word,
0,
0,
0,
0,
)
try:
ioctl(self.handle, SPI._IOC_MESSAGE, spi_ioc_transfer)
except TimeoutError as err:
raise Exception( # pylint: disable=broad-exception-raised
"ioctl timeout. Please try a different SPI frequency or less data."
) from err
def readbytes(self, length, max_speed_hz=0, bits_per_word=0, delay=0):
"""Perform half-duplex SPI read as a binary string"""
receive_buffer = create_string_buffer(length)
spi_ioc_transfer = struct.pack(
SPI._IOC_TRANSFER_FORMAT,
0,
addressof(receive_buffer),
length,
max_speed_hz,
delay,
bits_per_word,
0,
0,
0,
0,
)
ioctl(self.handle, SPI._IOC_MESSAGE, spi_ioc_transfer)
return string_at(receive_buffer, length)
def transfer(self, data, max_speed_hz=0, bits_per_word=0, delay=0):
"""Perform full-duplex SPI transfer"""
data = array.array("B", data).tobytes()
receive_data = []
chunks = [
data[i : i + self.chunk_size] for i in range(0, len(data), self.chunk_size)
]
for chunk in chunks:
length = len(chunk)
receive_buffer = create_string_buffer(length)
transmit_buffer = create_string_buffer(chunk)
spi_ioc_transfer = struct.pack(
SPI._IOC_TRANSFER_FORMAT,
addressof(transmit_buffer),
addressof(receive_buffer),
length,
max_speed_hz,
delay,
bits_per_word,
0,
0,
0,
0,
)
ioctl(self.handle, SPI._IOC_MESSAGE, spi_ioc_transfer)
receive_data += string_at(receive_buffer, length)
return receive_data