While testing with the dev sample I tried 3 different USB-C chargers. Asking the PMIC using
sensors tcpm_source_psy_4_0022-i2c-4-22 I got the following:
With a ‘dumb’ 15W RPi USB-C power brick (not USB PD compliant) obviously we’re ending up with 15W:
in0: 5.00 V (min = +5.00 V, max = +5.00 V) curr1: 3.00 A (max = +3.00 A)
With some 24W USB-C charger 18W get negotiated:
in0: 12.00 V (min = +12.00 V, max = +12.00 V) curr1: 1.50 A (max = +1.50 A)
And with an Apple ‘96W USB-C Power Adapter’ we’re at 27W:
in0: 9.00 V (min = +9.00 V, max = +9.00 V) curr1: 3.00 A (max = +3.00 A)
Is there already an advice how we can convince PMIC or USB PD chip to negotiate different settings?
And any chance to power the board differently e.g. 5V via GPIO header?