class MTSMBus(I2CBus):
""" Multi-thread compatible SMBus bus.
This is just a wrapper of SMBus, serializing I/O on the bus for use
in multi-threaded context and adding _i2c_ variants of block transfers.
"""
def __init__(self, bus_id=1, **kwargs):
"""
:param int bus_id: the SMBus id (see Raspberry Pi documentation)
:param kwargs: parameters transmitted to :py:class:`smbus.SMBus` initializer
"""
I2CBus.__init__(self, **kwargs)
self._bus = SMBus(bus_id)
# I/O serialization lock
self._lock = threading.Lock()
def read_byte(self, addr):
with self._lock:
return self._bus.read_byte(addr)
def write_byte(self, addr, data):
with self._lock:
self._bus.write_byte(addr, data)
def read_byte_data(self, addr, reg):
with self._lock:
return self._bus.read_byte_data(addr, reg)
def write_byte_data(self, addr, reg, data):
with self._lock:
self._bus.write_byte_data(addr, reg, data)
def read_word_data(self, addr, reg):
with self._lock:
return self._bus.read_word_data(addr, reg)
def write_word_data(self, addr, reg, data):
with self._lock:
self._bus.write_word_data(addr, reg, data)
def read_block_data(self, addr, reg):
with self._lock:
return self._bus.read_block_data(addr, reg)
def write_block_data(self, addr, reg, data):
with self._lock:
self._bus.write_block_data(addr, reg, data)
def read_i2c_block_data(self, addr, reg, count):
with self._lock:
return self._bus.read_i2c_block_data(addr, reg, count)
def write_i2c_block_data(self, addr, reg, data):
with self._lock:
self._bus.write_i2c_block_data(addr, reg, data)
class I2c(object):
def __init__(self):
self.bus_id = 0
self.smbus = SMBus(self.bus_id)
sda_pin = I2C_MAPPINGS['I2C_SDA']
scl_pin = I2C_MAPPINGS['I2C_SCL']
sda_pin.select()
scl_pin.select()
def value(self):
vals = self.smbus.read_block_data(0x02, 0x42)
print vals
class LocalhostSMBusSlave(SMBusSlave):
def __init__(self, bus, address):
SMBusSlave.__init__(self, bus, address)
self.bus = SMBus(bus)
self.address = address
#return: one byte hex string without '0x': '12'
def get_byte(self, offset):
# print "%s %s" % (datetime.datetime.utcnow().strftime("%H:%M:%S.%f")[:-4], sys._getframe().f_code.co_name)
ret = self.bus.read_byte_data(self.address, offset)
time.sleep(self.interval)
data = hex(ret)
return data[2:].zfill(2)
#input: offset:str, data:int
def set_byte(self, offset, data):
# print "%s %s" % (datetime.datetime.utcnow().strftime("%H:%M:%S.%f")[:-4], sys._getframe().f_code.co_name)
self.bus.write_byte_data(self.address, offset, data)
time.sleep(self.interval)
#return: two byte hex string without '0x': '1234'
def get_word(self, offset):
# print "%s %s" % (datetime.datetime.utcnow().strftime("%H:%M:%S.%f")[:-4], sys._getframe().f_code.co_name)
ret = self.bus.read_word_data(self.address, offset)
data = hex(ret)
time.sleep(self.interval)
return data[2:].zfill(4)
def set_word(self, offset, data):
# print "%s %s" % (datetime.datetime.utcnow().strftime("%H:%M:%S.%f")[:-4], sys._getframe().f_code.co_name)
if sys.byteorder == "big":
data = ((data & 0xff00) >> 8) + ((data & 0x00ff) << 8)
self.bus.write_word_data(self.address, offset, data)
time.sleep(self.interval)
#return: hex string list per byte,without '0x' :['12', '0a']
def get_block(self, offset, length="32"):
# print "%s %s" % (datetime.datetime.utcnow().strftime("%H:%M:%S.%f")[:-4], sys._getframe().f_code.co_name)
ret = self.bus.read_block_data(self.address, offset)
time.sleep(self.interval)
hex_ret = [hex(i)[2:].zfill(2) for i in ret]
return hex_ret
def set_block(self, offset, data):
# print "%s %s" % (datetime.datetime.utcnow().strftime("%H:%M:%S.%f")[:-4], sys._getframe().f_code.co_name)
data_arr = [(data & 0x00ff), ((data & 0xff00) >> 8)]
#self.bus.write_i2c_block_data(self.address, offset, data_arr)
self.bus.write_block_data(self.address, offset, data_arr)
time.sleep(self.interval)
class I2CDevice:
def __init__(self, addr=None, addr_default=None, bus=BUS_NUMBER):
if not addr:
# try autodetect address, else use default if provided
try:
self.addr = int('0x{}'.format(
findall("[0-9a-z]{2}(?!:)", check_output(['/usr/sbin/i2cdetect', '-y', str(BUS_NUMBER)]).decode())[0]), base=16) \
if exists('/usr/sbin/i2cdetect') else addr_default
except:
self.addr = addr_default
else:
self.addr = addr
self.bus = SMBus(bus)
# write a single command
def write_cmd(self, cmd):
self.bus.write_byte(self.addr, cmd)
sleep(0.0001)
# write a command and argument
def write_cmd_arg(self, cmd, data):
self.bus.write_byte_data(self.addr, cmd, data)
sleep(0.0001)
# write a block of data
def write_block_data(self, cmd, data):
self.bus.write_block_data(self.addr, cmd, data)
sleep(0.0001)
# read a single byte
def read(self):
return self.bus.read_byte(self.addr)
# read
def read_data(self, cmd):
return self.bus.read_byte_data(self.addr, cmd)
# read a block of data
def read_block_data(self, cmd):
return self.bus.read_block_data(self.addr, cmd)
class LinuxI2cBus:
"""A Linux I²C device, which is itself an I²C bus.
Should not be instantiated directly; use `LinuxI2c.find_devices`
instead.
This type mimics the `smbus.SMBus` read/write/close APIs. However,
`open` does not take any parameters, and not all APIs are available.
"""
# note: this is not a liquidctl BaseBus, as that would cause
# find_liquidctl_devices to try to directly instantiate it
def __init__(self, i2c_dev):
self._i2c_dev = i2c_dev
self._smbus = None
try:
assert i2c_dev.name.startswith('i2c-')
self._number = int(i2c_dev.name[4:])
except:
raise ValueError(f'cannot infer bus number')
def find_devices(self, drivers, **kwargs):
"""Probe drivers and find compatible devices in this bus."""
for drv in drivers:
yield from drv.probe(self, **kwargs)
def open(self):
"""Open the I²C bus."""
if not self._smbus:
try:
self._smbus = SMBus(self._number)
except FileNotFoundError:
if Path('/sys/class/i2c-dev').exists():
raise
raise OSError('kernel module i2c-dev not loaded') from None
def read_byte(self, address):
"""Read a single byte from a device."""
value = self._smbus.read_byte(address)
_LOGGER.debug('read byte @ 0x%02x: 0x%02x', address, value)
return value
def read_byte_data(self, address, register):
"""Read a single byte from a designated register."""
value = self._smbus.read_byte_data(address, register)
_LOGGER.debug('read byte data @ 0x%02x:0x%02x: 0x%02x', address,
register, value)
return value
def read_word_data(self, address, register):
"""Read a single 2-byte word from a given register."""
value = self._smbus.read_word_data(address, register)
_LOGGER.debug('read word data @ 0x%02x:0x%02x: 0x%04x', address,
register, value)
return value
def read_block_data(self, address, register):
"""Read a block of up to 32 bytes from a given register."""
data = self._smbus.read_block_data(address, register)
_LOGGER.debug('read block data @ 0x%02x:0x%02x: %r', address,
register, LazyHexRepr(data))
return data
def write_byte(self, address, value):
"""Write a single byte to a device."""
_LOGGER.debug('writing byte @ 0x%02x: 0x%02x', address, value)
return self._smbus.write_byte(address, value)
def write_byte_data(self, address, register, value):
"""Write a single byte to a designated register."""
_LOGGER.debug('writing byte data @ 0x%02x:0x%02x: 0x%02x', address,
register, value)
return self._smbus.write_byte_data(address, register, value)
def write_word_data(self, address, register, value):
"""Write a single 2-byte word to a designated register."""
_LOGGER.debug('writing word data @ 0x%02x:0x%02x: 0x%04x', address,
register, value)
return self._smbus.write_word_data(address, register, value)
def write_block_data(self, address, register, data):
"""Write a block of byte data to a given register."""
_LOGGER.debug('writing block data @ 0x%02x:0x%02x: %r', address,
register, LazyHexRepr(data))
return self._smbus.write_block_data(address, register, data)
def close(self):
"""Close the I²C connection."""
if self._smbus:
self._smbus.close()
self._smbus = None
def load_eeprom(self, address):
"""Return EEPROM name and data in `address`, or None if N/A."""
# uses kernel facilities to avoid directly reading from the EEPROM
# or managing its pages, also avoiding the need for unsafe=smbus
dev = f'{self._number}-{address:04x}'
try:
name = self._i2c_dev.joinpath(dev, 'name').read_text().strip()
eeprom = self._i2c_dev.joinpath(dev, 'eeprom').read_bytes()
return LinuxEeprom(name, eeprom)
except Exception as err:
return None
@property
def name(self):
return self._i2c_dev.name
@property
def description(self):
return self._try_sysfs_read('name')
@property
def parent_vendor(self):
return self._try_sysfs_read_hex('device/vendor')
@property
def parent_device(self):
return self._try_sysfs_read_hex('device/device')
@property
def parent_subsystem_vendor(self):
return self._try_sysfs_read_hex('device/subsystem_vendor')
@property
def parent_subsystem_device(self):
return self._try_sysfs_read_hex('device/subsystem_device')
@property
def parent_driver(self):
try:
return Path(
os.readlink(self._i2c_dev.joinpath('device/driver'))).name
except FileNotFoundError:
return None
def __str__(self):
if self.description:
return f'{self.name}: {self.description}'
return self.name
def __repr__(self):
def hexid(maybe):
if maybe is not None:
return f'{maybe:#06x}'
return 'None'
return f'{self.__class__.__name__}: name: {self.name!r}, ' \
f'description: {self.description!r}, ' \
f'parent_vendor: {hexid(self.parent_vendor)}, ' \
f'parent_device: {hexid(self.parent_device)}, ' \
f'parent_subsystem_vendor: {hexid(self.parent_subsystem_vendor)}, ' \
f'parent_subsystem_device: {hexid(self.parent_subsystem_device)}, ' \
f'parent_driver: {self.parent_driver!r}'
def _try_sysfs_read(self, *sub, default=None):
try:
return self._i2c_dev.joinpath(*sub).read_text().rstrip()
except FileNotFoundError:
return default
def _try_sysfs_read_hex(self, *sub, default=None):
try:
return int(self._i2c_dev.joinpath(*sub).read_text(), base=16)
except FileNotFoundError:
return default
class LinuxI2cBus:
"""A Linux I²C device, which is itself an I²C bus.
Should not be instantiated directly; use `LinuxI2c.find_devices`
instead.
This type mimics the `smbus.SMBus` read/write/close APIs. However,
`open` does not take any parameters, and not all APIs are available.
"""
# note: this is not a liquidctl BaseBus, as that would cause
# find_liquidctl_devices to try to directly instantiate it
def __init__(self, i2c_dev):
if not i2c_dev.name.startswith('i2c-'):
raise ValueError('not a bus or unsupported adapter')
self._i2c_dev = i2c_dev
self._smbus = None
self._number = int(i2c_dev.name[4:])
def find_devices(self, drivers, **kwargs):
"""Probe drivers and find compatible devices in this bus."""
for drv in drivers:
yield from drv.probe(self, **kwargs)
def open(self):
"""Open the I²C bus."""
if not self._smbus:
try:
self._smbus = SMBus(self._number)
except FileNotFoundError:
if Path('/sys/class/i2c-dev').exists():
raise
raise OSError('kernel module i2c-dev not loaded') from None
def read_byte(self, address):
"""Read a single byte from a device."""
value = self._smbus.read_byte(address)
_LOGGER.debug('read byte @ 0x%02x:0x%02x', address, value)
return value
def read_byte_data(self, address, register):
"""Read a single byte from a designated register."""
value = self._smbus.read_byte_data(address, register)
_LOGGER.debug('read byte data @ 0x%02x:0x%02x 0x%02x',
address, register, value)
return value
def read_word_data(self, address, register):
"""Read a single 2-byte word from a given register."""
value = self._smbus.read_word_data(address, register)
_LOGGER.debug('read word data @ 0x%02x:0x%02x 0x%02x',
address, register, value)
return value
def read_block_data(self, address, register):
"""Read a block of up to 32 bytes from a given register."""
data = self._smbus.read_block_data(address, register)
_LOGGER.debug('read block data @ 0x%02x:0x%02x: %r',
address, register, LazyHexRepr(data))
return data
def write_byte(self, address, value):
"""Write a single byte to a device."""
_LOGGER.debug('writing byte @ 0x%02x: 0x%02x', address, value)
return self._smbus.write_byte(address, value)
def write_byte_data(self, address, register, value):
"""Write a single byte to a designated register."""
_LOGGER.debug('writing byte data @ 0x%02x:0x%02x 0x%02x',
address, register, value)
return self._smbus.write_byte_data(address, register, value)
def write_word_data(self, address, register, value):
"""Write a single 2-byte word to a designated register."""
_LOGGER.debug('writing word data @ 0x%02x:0x%02x 0x%02x',
address, register, value)
return self._smbus.write_word_data(address, register, value)
def write_block_data(self, address, register, data):
"""Write a block of byte data to a given register."""
_LOGGER.debug('writing block data @ 0x%02x:0x%02x %r',
address, register, LazyHexRepr(data))
return self._smbus.write_block_data(address, register, data)
def close(self):
"""Close the I²C connection."""
if self._smbus:
self._smbus.close()
self._smbus = None
def load_eeprom(self, address):
"""Return EEPROM name and data in `address`, or None if N/A."""
# uses kernel facilities to avoid directly reading from the EEPROM
# or managing its pages, also avoiding the need for unsafe=smbus
dev = f'{self._number}-{address:04x}'
try:
name = self._i2c_dev.joinpath(dev, 'name').read_text().strip()
# work around a bug in the kernel by reading the ee1004 eeprom
# in small enough chunks
# related: #416 ("DDR4 support broken on Linux 5.16.3")
# related: https://lore.kernel.org/lkml/[email protected]/
eeprom_path = self._i2c_dev.joinpath(dev, 'eeprom')
eeprom_size = eeprom_path.stat().st_size
_LOGGER.debug('path=%s, size=%s', eeprom_path, eeprom_size)
with eeprom_path.open(mode='rb', buffering=0) as f:
eeprom = bytearray()
while len(eeprom) < eeprom_size:
b = f.read(128)
if not b:
break
eeprom.extend(b)
return LinuxEeprom(name, eeprom)
except FileNotFoundError:
return None
@property
def name(self):
return self._i2c_dev.name
@property
def description(self):
return self._try_sysfs_read('name')
@property
def parent_vendor(self):
return self._try_sysfs_read_hex('device/vendor')
@property
def parent_device(self):
return self._try_sysfs_read_hex('device/device')
@property
def parent_subsystem_vendor(self):
return self._try_sysfs_read_hex('device/subsystem_vendor')
@property
def parent_subsystem_device(self):
return self._try_sysfs_read_hex('device/subsystem_device')
@property
def parent_driver(self):
try:
return Path(os.readlink(self._i2c_dev.joinpath('device/driver'))).name
except FileNotFoundError:
return None
def __str__(self):
if self.description:
return f'{self.name}: {self.description}'
return self.name
def __repr__(self):
def hexid(maybe):
if maybe is not None:
return f'{maybe:#06x}'
return 'None'
return f'{self.__class__.__name__}: name: {self.name!r}, description:' \
f' {self.description!r}, parent_vendor: {hexid(self.parent_vendor)},' \
f' parent_device: {hexid(self.parent_device)}, parent_subsystem_vendor:' \
f' {hexid(self.parent_subsystem_vendor)},' \
f' parent_subsystem_device: {hexid(self.parent_subsystem_device)},' \
f' parent_driver: {self.parent_driver!r}'
def _try_sysfs_read(self, *sub, default=None):
try:
return self._i2c_dev.joinpath(*sub).read_text().rstrip()
except FileNotFoundError:
return default
def _try_sysfs_read_hex(self, *sub, default=None):
try:
return int(self._i2c_dev.joinpath(*sub).read_text(), base=16)
except FileNotFoundError:
return default
