dts: stepper: move m0/m1-gpios property in stepper-controller

[jilaypandya]

m0-gpios and m1-gpios are common in step-dir stepper drivers and hence placing them in common stepper-controller.yaml along with step-gpios and dir-gpios

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[dipakgmx]

This solution does not seem extensible. Drivers like A4988, DRV8825 support 3 pins for setting micro-stepping which would not work (or, say extend), in this case. A possible solution, would be to revert to the phandle logic for the microstepping pins, like earlier:

microstep-mode-gpios:
    type: phandle-array
    description: GPIO specifiers for microstepping pins.

& use the existing

  micro-step-res:
    type: int
    default: 1
    enum:
      - 1
      - 2
      - 4
      - 8
      - 16
      - 32
      - 64
      - 128
      - 256
    description: |
      micro-step resolution to be set while initializing the device driver.
      Use this only if the MS pins are hardwired to VCC/GND.

to determine the microstepping resolution in the case of hardwired pins.

Also, we can then enforce this exclusivity in the driver level (eiither set via gpio's or hardwired(static)).

[jilaypandya]

One could hardwire one pin, while still toggling the others via gpio. In this scenario, the idx of the pin getting toggled via gpio is important to know.The available micro-step resolutions would be reduced, but the application would still have the possibility to select.

We can extend the list as soon as one of the aforementioned drivers gets upstreamed.