boards: shields: Add Adafruit DS2484 1-wire shield

[pyhys]

Product photo from https://learn.adafruit.com/assets/130701 with license CC BY-SA 3.0

Tested with command mentioned in the index.rst page.

[Copilot]

Pull Request Overview

This PR adds support for the Adafruit DS2484 I2C to 1-Wire Bus Adapter as a Zephyr shield, enabling 1-wire device communication through I2C connectivity.

• Introduces a new shield configuration for the Adafruit DS2484 adapter
• Refactors test harness configuration to move from common to individual test level
• Adds shield-specific test case with appropriate platform configuration

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
boards/shields/adafruit_ds2484/shield.yml	Shield metadata defining name, vendor, and supported features
boards/shields/adafruit_ds2484/doc/index.rst	Complete documentation with overview, requirements, pin assignments, and usage examples
boards/shields/adafruit_ds2484/adafruit_ds2484.overlay	Device tree overlay configuring the DS2484 I2C device and w1 node aliases
boards/shields/adafruit_ds2484/Kconfig.shield	Kconfig shield selection configuration
samples/drivers/w1/scanner/sample.yaml	Test harness refactoring and addition of shield-specific test case

---

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[kartben]

what is the issue with the console harness and your shield?

[pyhys]

Maybe I have misunderstood how this works. Ideally I would like to test on hardware (an actual shield). However now I at least would like to have a build-only test. Will that give any output on a console? Any help is appreciated.

It seems to work locally if I change back to the original "common" setting and add

  sample.drivers.w1.scanner.shields:
    platform_allow:
      - adafruit_qt_py_rp2040/rp2040
    extra_args:
      - platform:adafruit_qt_py_rp2040/rp2040:SHIELD="adafruit_ds2484"
    harness_config:
      type: one_line

Is that a better way?

[str4t0m]

Two minor notes.

[pyhys]

@str4t0m I modified the sample.yaml to

  sample.drivers.w1.scanner.shields:
    platform_allow:
      - adafruit_qt_py_rp2040/rp2040
    integration_platforms:
      - adafruit_qt_py_rp2040/rp2040
    extra_args:
      - platform:adafruit_qt_py_rp2040/rp2040:SHIELD="adafruit_ds2484"
    harness_config:
      type: one_line
      regex:
        - "Number of devices found on bus: .*"

Then I can compile-test the overlay file locally with:

scripts/twister -T samples/drivers/w1/scanner -v -v --platform adafruit_qt_py_rp2040

and the resulting twister.json contains:

{
    "environment":{
        "os":"posix",
        "zephyr_version":"v4.2.0-2542-g04c885d95a85",
        "toolchain":"zephyr",
        "commit_date":"2025-09-21T13:38:57+02:00",
        "run_date":"2025-09-21T11:45:22+00:00",
        "options":{
            "testsuite_root":[
                "samples/drivers/w1/scanner"
            ],
            "platform":[
                "adafruit_qt_py_rp2040"
            ],
            "verbose":2
        }
    },
    "testsuites":[
        {
            "name":"sample.drivers.w1.scanner.shields",
            "arch":"arm",
            "platform":"adafruit_qt_py_rp2040/rp2040",
            "path":"samples/drivers/w1/scanner",
            "run_id":"62b42d4b391360108177f6360ec147af",
            "runnable":false,
            "retries":0,
            "toolchain":"zephyr",
            "status":"not run",
            "reason":"Unknown",
            "execution_time":"0.00",
            "build_time":"23.39",
            "testcases":[
                {
                    "identifier":"sample.drivers.w1.scanner.shields",
                    "execution_time":"0.00",
                    "status":"not run",
                    "reason":"Test was built only"
                }
            ]
        }
    ]
}

[pyhys]

When I connect the shield to an adafruit_qt_py_rp2040, manually set the board to bootloader mode, and run:

scripts/twister -T samples/drivers/w1/scanner -v -v --platform adafruit_qt_py_rp2040  --device-testing --device-serial /dev/ttyUSB0

the result is a passing device test:

{
    "environment":{
        "os":"posix",
        "zephyr_version":"v4.2.0-2542-g04c885d95a85",
        "toolchain":"zephyr",
        "commit_date":"2025-09-21T13:38:57+02:00",
        "run_date":"2025-09-21T17:13:50+00:00",
        "options":{
            "testsuite_root":[
                "samples/drivers/w1/scanner"
            ],
            "device_testing":true,
            "device_serial":"/dev/ttyUSB0",
            "platform":[
                "adafruit_qt_py_rp2040"
            ],
            "verbose":2
        }
    },
    "testsuites":[
        {
            "name":"sample.drivers.w1.scanner.shields",
            "arch":"arm",
            "platform":"adafruit_qt_py_rp2040/rp2040",
            "path":"samples/drivers/w1/scanner",
            "run_id":"a3831980448e8ef45b7970b2573d90ce",
            "runnable":true,
            "retries":0,
            "toolchain":"zephyr",
            "status":"passed",
            "execution_time":"2.82",
            "build_time":"24.60",
            "testcases":[
                {
                    "identifier":"sample.drivers.w1.scanner.shields",
                    "execution_time":"2.82",
                    "status":"passed"
                }
            ]
        }
    ]
}

[pyhys]

So what is the consensus @str4t0m @JarmouniA @kartben ?
Should I do any more changes to this PR?

[JarmouniA]

So what is the consensus @str4t0m @JarmouniA @kartben ? Should I do any more changes to this PR?

In my opinion, no, the problem of testing with shields is general, not specific to this PR.

[str4t0m]

If you have a chance could you please add the fixture as discussed on weekend above.

Good, @JarmouniA would it be fine for you if we add the fixture line for now, since we don't have anything better yet, and you propose an RFC issue or a PR introducing the shield filter. And after the shield filter has landed I'll convert the 1-Wire tests to use the shield filter where applicable?

[pyhys]

Rebased on main to fix CI issues.

[pyhys]

@JarmouniA and @str4t0m How do we proceed with this PR? Can it be merged now and the fixture be added later?

[str4t0m]

@pyhys It guess you have seen my proposal in comment? I would still prefer if you could add it here, as it would be just adding a single line. But if not, I can approve the PR and open a PR on the weekend to fix the issue.

[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

[pyhys]

@str4t0m OK, I did not understand what to do previously. Now I added the fixture line. Can you please have a look to see that it is correct?

[str4t0m]

Great, thanks! Yes that what I meant.