Remove interrupts_enabled from Timers and Gpio

[rrbutani]

what

The Input and Output traits have this method because whether or not interrupts are enabled is truly orthogonal to the current state of the peripheral: it's possible for the peripheral to be ready (i.e. to have data (Input) or to be ready to accept data (Output)) regardless of whether interrupts are enabled or disabled (#182).

This is not the case for Gpio and Timers.

Gpio

core/traits/src/peripherals/gpio.rs

Lines 269 to 272 in 5e0f0eb

	#[inline]
	fn interrupts_enabled(&self, pin: GpioPin) -> bool {
	matches!(self.get_state(pin), GpioState::Interrupt)
	}

For Gpio, it's only valid for the peripheral to produce interrupts when a pin is in Interrupt mode. This makes Gpio::interrupts_enabled entirely redundant: you'd never want anything but the default interrupts_enabled impl.

Timers

core/traits/src/peripherals/timers.rs

Lines 260 to 264 in 5e0f0eb

	#[inline]
	fn interrupts_enabled(&self, timer: TimerId) -> bool {
	matches!(self.get_state(timer), TimerState::WithPeriod(_)) ||
	(self.get_state(timer) == TimerState::Disabled && self.interrupt_occurred(timer))
	}

For Timers there isn't an enable/disable for interrupts because there is no other mode of use for Timers other than interrupts.

When a timer has fired there is an interrupt pending. Clearing that interrupt flag means there is no longer an interrupt pending and there are no additional states.

steps

• remove the interrupts_enabled functions from Timers and Gpio
• adjust mem_mapped in baseline-sim to match
• update the docs on the Timers and Gpio traits

where

branch: imp/remove-interrupts-enables-function

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