espressif: correct ESP32-P4 ADC2 channel mapping

[ladyada-eagleclaw]

AI-assisted with Codex during Metro ESP32-P4 bring-up; the results below come from local builds and serial captures.

GPIO49–54 map to ADC2 channels 0–5, but the P4 pin table used channels 2–7. Correct the six entries. Before this change, A4 and A5 failed with IDFError('Invalid argument') and IDFError('Requested resource not found').

Tested on Adafruit Metro ESP32-P4 Rev A, silicon v0.1, running the 10.3.0-alpha.4 development tree:

import analogio, board
for name in ('A0', 'A1', 'A2', 'A3', 'A4', 'A5'):
    with analogio.AnalogIn(getattr(board, name)) as pin:
        print(name, pin.value)

All six inputs constructed and read successfully. Recorded values were 49210, 59656, 60629, 61305, 61205, and 61046. These were floating inputs, so this verifies channel access, not voltage accuracy.

The combined bring-up tree built for Metro, P4 GPIO, both Espressif P4 function EV variants, M5Stack Tab5, and Solder Party P4 Stamp XL using make -C ports/espressif BOARD=<board> -j6. Hardware testing used the combined tree; this PR isolates the mapping correction on current main. Changed-file pre-commit and git diff --check pass. Other boards were compile-tested only.

[Copilot]

Copilot review overview

🟢 Approval recommended

The focused mapping correction is consistent, complete, and supported by hardware and compile testing.

Review effort: Balanced
Findings: None

What changed in this PR

Corrects ESP32-P4 ADC2 pin metadata to match the GPIO49–54 hardware channel mapping.

Changes:

• Remaps GPIO49–54 from ADC2 channels 2–7 to channels 0–5.
• Restores analog input access for affected ESP32-P4 boards.

File	Description
ports/​espressif/​peripherals/​esp32p4/​pins.c	Corrects six ADC2 channel assignments.

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[mikeysklar]

Reviewed, looks good to me.

[dhalbert]

👍