fix #4367 make USB power detection work correctly on seeed trackers

[geeksville]

for wio tracker 1110 and 1000-E and possibly other nrf52 boards. The problem was that nrf52 power stuff wasn't generating regular powerstatus notifications (because that code was guarded by a batteryLevel check which was null for those boards). So I've cleaned up the battery status stuff a bit and we now have fewer special cases.
Tested on a 1000-E, tracker 1110 and a rak4631 board.

(fix #4367)

[thebentern]

Legend!
I be willing to bet that's a regression from some of the recent work on using INA sensors for device battery level voltage.

[fifieldt]

nice! Care to add to the wio-sdk-wm1110 too?

[geeksville]

nice! Care to add to the wio-sdk-wm1110 too?

hmm - I'm not sure if it will work there because on that board the USB isn't really going to the nrf52840, instead it is going to a little USB serial chip (oops). I'll check the schematic though.

[geeksville]

@fifieldt just checked schematic. Alas, this approach won't work for that board.

Btw is a bummer they forgot to include (at-least) a voltage-divider circuit to let the CPU sense the battery voltage (as far as I can tell - haven't checked super carefully).

I hope they included battery level sensing in the 1000-E board because if they didn't: ouch.

[geeksville]

oh they did for the 1000-E. good!

#define BATTERY_PIN 2
#define ADC_MULTIPLIER (2.0F)

#define ADC_RESOLUTION 14
#define BATTERY_SENSE_RESOLUTION_BITS 12

[fifieldt]

ah! I forgot about that. Thank you very much for investigating.