i2c is not unlocked with soft reset on 6.2.0

[kevinjwalters]

On 6.2.0 on a Feather nRF52840 Express using the singleton from board.I2C():

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Adafruit CircuitPython 6.2.0 on 2021-04-05; Adafruit Feather nRF52840 Express with nRF52840
>>> import board
>>> i2c = board.I2C()
>>> i2c.try_lock()
True
>>> ["{:2x}".format(x) for x in i2c.scan()]
[' 8', '23', '76']
>>> ["{:02x}".format(x) for x in i2c.scan()]
['23', '76']
>>> ["{:02x}".format(x) for x in i2c.scan()]
['23', '76']
>>>  ### Control-D here then Control-C after that to interrupt
soft reboot

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code.py output:
Traceback (most recent call last):
  File "code.py", line 40, in <module>
  File "/lib/pimoroni_pms5003/__init__.py", line 167, in <module>
  File "/lib/pimoroni_pms5003/__init__.py", line 189, in PMS5003
KeyboardInterrupt:

Code done running.

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Adafruit CircuitPython 6.2.0 on 2021-04-05; Adafruit Feather nRF52840 Express with nRF52840
>>> import board
>>> i2c = board.I2C()
>>> i2c.try_lock()
False
>>> i2c.try_lock()
False
>>> i2c.try_lock()
False
>>> i2c.unlock()
>>> i2c.try_lock()
True
>>> ["{:02x}".format(x) for x in i2c.scan()]
['23', '76']
>>> i2c.unlock()

Similar theme to #3266

[dhalbert]

TThanks! This is a very old bug. It has been true since 5.0.0, probably ever since we started supporting I2C displays. shared-module/busio/__init__.c needs to unlock the board.I2C() object, as it already does to to the board.SPI() object.

[kevinjwalters]

Did I dupe an existing issue? I had a quick look and couldn't find anything obvious.

[dhalbert]

Did I dupe an existing issue? I had a quick look and couldn't find anything obvious.

No, I just mean it has lain undiscovered for quite a while.

[kevinjwalters]

Unrelated to the issue here, there's a strange address 0x08 (device?) in there which appears on first query and not afterwards. I've got it attached to a Pimoroni Enviro+ FeatherWing which has an LTR-559 (0x23) and BME280 (0x76) and nothing else AFAIK...

[dhalbert]

Unrelated to the issue here, there's a strange address 0x08 (device?) in there which appears on first query and not afterwards. I've got it attached to a Pimoroni Enviro+ FeatherWing which has an LTR-559 (0x23) and BME280 (0x76) and nothing else AFAIK...

Bring this up in another issue if you think it's a CircuitPython issue. But it might be some I2C device issue.