Input Enable now turned off on ADC capable GPIOs (Errata RP2040-E6) about rp-hal HOT 2 CLOSED

We have a function to manually set the Input Enable bit: https://docs.rs/rp2040-hal/latest/rp2040_hal/gpio/struct.Pin.html#method.set_input_enable

However, should it be set automatically when configuring a pin to some other function mode?

Also, on stepping B0 and B1, the IE bit gets disabled by the SDK "as early as possible after startup".
Perhaps we should do the same? I assume this is a precautionary measure to avoid metastabilities due to undefined digital values.

from rp-hal.

Yes, we should probably do the same. If the user asks for DynFunction::SioXXX, or DynFunction::I2C, or DynFunction::SPI or whatever, we should set the Input Enable on and Output Disable off for the pad . At startup (which is DynFunction::Null) and if they ask for DynFunction::ADC, we should set Input Enable off and Output Disable on.

If they want to fiddle with the settings after picking the function, we can let them do that. But selecting a function should be sufficient, for any RP2040 GPIO.

I assume this is a precautionary measure to avoid metastabilities due to undefined digital values.

If you hold the ADC input mid-rail (not unreasonable) but the digital input is enabled, I think it draws a ton of current.

from rp-hal.