Here are a couple of responses from my side:
Thank you very much for confirming this! The only reasonable explanation is that plugging a charger into the official dock causes the dock to provide 5 V prior to any negotiation with the upstream USB port (i.e. the phone), which in turn causes the PMIC to enter the power-on procedure. This is probably a bug in the official dock.
As already noted, this is simply part of the behavior of the AXP803; if it detects valid input voltage, it automatically starts the power-on procedure. Here are a couple of quotations from page 25 of the AXP803 datasheet that describe this:
It could very well be that I'm missing something, but the AXP803 datasheet describes no means to change this behavior of the AXP803.
(03-14-2021, 08:29 PM)bokomaru Wrote: Phone -> convergence dock -> USB C to a cable -> old "dumb" power brick -> AC wall outlet: Connecting the first time causes the phone to power on. After powering off the phone from software, the phone powers back on; won't stay "off".
Thank you very much for confirming this! The only reasonable explanation is that plugging a charger into the official dock causes the dock to provide 5 V prior to any negotiation with the upstream USB port (i.e. the phone), which in turn causes the PMIC to enter the power-on procedure. This is probably a bug in the official dock.
(03-14-2021, 08:29 PM)bokomaru Wrote:(03-14-2021, 07:42 AM)megous Wrote: anx7688 doesn't do anything unless the pinephone is powered on, so there's some fun to be had when charging via USB-PD chargers when the phone is off.
Maybe that's related to this, i.e., maybe the phone powers on by design, so that USB-PD can be negotiated if applicable.
I also remember reading that, for similar reasons, while charging, Android phones tend to be booted up. At least into the bootloader, and then the bootloader maybe knows to enter a different "charging indication" mode or to "stop here" until X or Y event happens.
As already noted, this is simply part of the behavior of the AXP803; if it detects valid input voltage, it automatically starts the power-on procedure. Here are a couple of quotations from page 25 of the AXP803 datasheet that describe this:
Quote:Power on source
Below are the 2 power up sources supported by AXP803 in mechanical off state:
1. Charger insertion (including ACIN and VBUS insertion);
2. Power on key pressed
Quote:Power on from charger insertion
The PMIC will start the power on sequence by a charger insertion. A charger insertion is detected from a rising voltage on the ACIN/VBUS node. If 4.1 V < ACIN/VBUS < 7.0 V, the charger will start charging immediately and autonomously. The existence of ACIN/VBUS is stored in REG 00H[7/5 ].
It could very well be that I'm missing something, but the AXP803 datasheet describes no means to change this behavior of the AXP803.
