nordic: hardware pulse counting

[jodzik]

Is your feature request related to a problem? Please describe.
I need several simple pulse counter, but signals has a high frequency(up to 1Mhz), therefore interrupt-based implementation may be too demanding on CPU.
nRF52832(in may case) and similar hardware are capable of hardware pulse counting, implementation of this can solve the problem.

Describe the solution you'd like
A sensor driver like /drivers/sensor/espressif/pcnt_esp32/
DTS may look like:

&pulse_counter {
    compatible = "nordic,pcnt"
    status = "okay";
    gpios = <&gpio0 26 GPIO_ACTIVE_LOW>;
    timer = <&timer4>;
    mode = "...";
}

OR

&timer4 {
    status = "okay";
    pulse_counter0: pulse_counter0 {
        compatible = "nordic,pcnt"
        status = "okay";
        mode = "...";
        gpios = <&gpio0 26 GPIO_ACTIVE_LOW>;
    }
}

Maybe it's better to use pinctl node to select GPIOTE/pin.

Describe alternatives you've considered
Use nrfx directly or use external driver(e.g.).

[github-actions]

Hi @jodzik! We appreciate you submitting your first issue for our open-source project. 🌟

Even though I'm a bot, I can assure you that the whole community is genuinely grateful for your time and effort. 🤖💙

[sayooj-aerlync]

Would it not be better to add a generic implementation so that all supported platforms can make use of it?
A fall back mechanism to software (with its limitations) can also be added if needed.

[jodzik]

Would it not be better to add a generic implementation so that all supported platforms can make use of it? A fall back mechanism to software (with its limitations) can also be added if needed.

I think this solution would be perfect.