Increase charge restart time
charge: Factor out sensor sampling
Move NOT_USED into util.h
charge: Export sample cache
Use button to query charge state
Fix R6 value

2.2kohm is close enough to 2.5kohm
usart: Ensure we don't call NULL
Use 56k and 10k for USB regulator
charge: Update pinning
adc: Ensure last sample get written
charge: Add debug output
charge: Add newline
Fix charge voltage to offset calculation
charge: Fix charge_en pin
charge: Reset to slightly above battery voltage