gpiod support - Githubissues

to make python version portable want to move to gpiod, but there are MANY python libs.

They both have different APIs.

Others;

https://wiki.loliot.net/docs/lang/python/libraries/gpiod/python-gpiod-about/
le potato - uses command line tools? https://github.com/c0t088/libregpio
- https://libregpio.readthedocs.io/en/latest/
https://github.com/tnyeanderson/anygpio no support yet but worth considering
https://github.com/gustavsl/pygpiod
https://pypi.org/project/gpiodcxx/
- https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git
https://circuitpython.org/blinka
- https://docs.circuitpython.org/en/latest/shared-bindings/digitalio/index.html

problem with current ones tried is conflict with SPI pin:

(py3venv) pi@pizero:~/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python $ cat cs_issue.py

import gpiod  # expected to be sudo apt install python3-libgpiod  # https://www.acmesystems.it/libgpiod#:~:text=Manage%20GPIO%20lines%20in%20Python3%20and%20C%20with,calls%20and%20data%20structures%20behind%20a%20straightforward%20API.

print(dir(gpiod))
print(gpiod.__file__)
print(gpiod.version_string())

CS_PIN = 8
chip = gpiod.Chip('gpiochip0')
"""
$ gpioinfo |grep 8
        line   8:      unnamed   "spi0 CS0"  output   active-low [used]

"""
_CS_PIN = chip.get_line(CS_PIN)
_CS_PIN.request(consumer=__file__, type=gpiod.LINE_REQ_DIR_OUT)

(py3venv) pi@pizero:~/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python $ cat alt_cs_issue.py

import gpiod  # expected to be https://github.com/hhk7734/python3-gpiod
print(dir(gpiod))
print(gpiod.__file__)

CS_PIN = 8
chip = gpiod.chip('gpiochip0')
"""
$ gpioinfo |grep 8
        line   8:      unnamed   "spi0 CS0"  output   active-low [used]

"""
_CS_PIN = chip.get_line(CS_PIN)
config = gpiod.line_request()
config.consumer = __file__
config.request_type = gpiod.line_request.DIRECTION_OUTPUT

_CS_PIN.request(config=config)

errors:

(py3venv) pi@pizero:~/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python $ python alt_cs_issue.py
['__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__path__', '__spec__', 'chip', 'chip_iter', 'find_line', 'kernel', 'libgpiod', 'libgpiodcxx', 'line', 'line_bulk', 'line_event', 'line_iter', 'line_request', 'make_chip_iter']
/home/pi/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python/py3venv/lib/python3.7/site-packages/gpiod/__init__.py
Traceback (most recent call last):
  File "alt_cs_issue.py", line 17, in <module>
    _CS_PIN.request(config=config)
  File "/home/pi/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python/py3venv/lib/python3.7/site-packages/gpiod/libgpiodcxx/__init__.py", line 572, in request
    rv = libgpiod.gpiod_line_request(_m_line, conf, default_val)
  File "/home/pi/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python/py3venv/lib/python3.7/site-packages/gpiod/libgpiod/__init__.py", line 499, in gpiod_line_request
    return gpiod_line_request_bulk(bulk, config, [default_val])
  File "/home/pi/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python/py3venv/lib/python3.7/site-packages/gpiod/libgpiod/__init__.py", line 542, in gpiod_line_request_bulk
    return _line_request_values(bulk, config, default_vals)
  File "/home/pi/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python/py3venv/lib/python3.7/site-packages/gpiod/libgpiod/__init__.py", line 403, in _line_request_values
    status = ioctl(fd, GPIO_GET_LINEHANDLE_IOCTL, req)
OSError: [Errno 16] Device or resource busy

pi@pizero:~/c/eink_ssd1619_er-epm042-1/ER-EPM042-1_Raspberry_Pi/ER-EPM042A1-1R/python $ python3 cs_issue.py
['Chip', 'ChipIter', 'LINE_REQ_DIR_AS_IS', 'LINE_REQ_DIR_IN', 'LINE_REQ_DIR_OUT', 'LINE_REQ_EV_BOTH_EDGES', 'LINE_REQ_EV_FALLING_EDGE', 'LINE_REQ_EV_RISING_EDGE', 'LINE_REQ_FLAG_ACTIVE_LOW', 'LINE_REQ_FLAG_OPEN_DRAIN', 'LINE_REQ_FLAG_OPEN_SOURCE', 'Line', 'LineBulk', 'LineEvent', 'LineIter', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', 'find_line', 'version_string']
/usr/lib/python3/dist-packages/gpiod.cpython-37m-arm-linux-gnueabihf.so
1.2
Traceback (most recent call last):
  File "cs_issue.py", line 15, in <module>
    _CS_PIN.request(consumer=__file__, type=gpiod.LINE_REQ_DIR_OUT)
OSError: [Errno 16] Device or resource busy

clach04 / eink_ssd1619_er-epm042-1

gpiod support #1