drivers: video: csi: Change sensor dev to source dev

[ngphibang]

The CSI can connect to either a camera sensor (as on i.MX RT10xx) or a MIPI CSI-2 receiver (as on i.MX RT11xx). To be generic, change the naming from sensor dev to source dev.

This PR is splitted from #69810 to ease the review process and from #72420 to avoid mutual dependency with #71859

[ngphibang]

Hi,
Could we merge this one in priority as the PR is rather trivial (just a renaming) and it is a dependency for several PRs ?

[josuah]

sensor is also causing confusion with the sensor driver API. Good to rename it.

sdev could be thought as stream-dev, or source-dev, or sink-dev or subdev (which conveniently mimicks Linux subdev API, which is kind of the purpose here...)

A sink could also be an associated device, such as the HDMI to MIPI bridges chips 1, 2, or HDMI CEC controllers 1.

An alternative is to use remote-endpoint for this, so that for instance, some source with many ports/endpoint, and different resolution per ports can get controls specific to every port declare. Probably not going to happen before one of such complex video device becomes supported by Zephyr though...

P.S.: There is a chat channel #pr-help dedicated to catching attention onto a PR.
There is currently no maintainer for the video subsystem, which means lower guarantee of response time.

[decsny]

this name is not descriptive, also is this worth breaking backward compatibility

[ngphibang]

@decsny : I can change to "source_dev" (?) to be more descriptive. But the old name "sensor" is definitely not ok for the new support in RT11xx. As explained in the commit message, "sensor" is chosen because at that time, the CSI driver supports only RT10xx where it connects to a sensor. But in RT11xx, it connects to MIPI CSI2 instead.

[decsny]

ok

[ngphibang]

ok, done

[loicpoulain]

Can we simply name it 'source'

[ngphibang]

Yes, done. But now, I need @danieldegrasse and @decsny approve the PR again ...