Hibernate (deep sleep) leaves the BQ25896 charger IC powered, drawing
~30-60uA quiescent from BAT. This adds a second option on the shutdown
page -- "power off" -- that writes the BATFET_DIS bit in BQ25896 REG09
to fully disconnect the battery from VSYS. Leakage drops to ~12-23uA
(IC internal only). Wake requires USB-C plug-in.
Shutdown page now shows two options with a cursor (up/down to toggle):
> hibernate: long press/Enter (T-Deck Pro)
power off: long press/Enter
> hibernate: long press (T5S3 / other)
power off: long press
Selecting "hibernate" triggers immediately (unchanged behaviour).
Selecting "power off" shows a confirmation prompt:
power off device?
usb-c to wake
Enter:yes q:no
Power-off display suppresses the header (node name, clock, battery)
and shows only "powering off..." and "plug in USB-C to turn on".
The 's' key shortcut to settings is gated on the shutdown page so it
passes through to the hibernate/power-off selection toggle instead.
Both the TCA8418 handler (loop) and the broader handler
(handleKeyboardInput) are gated via isHomeOnShutdownPage().
PRESS_LABEL macro: removed dead UI_HAS_JOYSTICK branch (no Meck
device has a joystick), collapsed to a single #define "long press".
Joystick input polling block in loop() also removed (dead code behind
#if UI_HAS_JOYSTICK, never compiled for any Meck build).
BQ25896 I2C sequence follows TI recommendation (E2E forum, Jeff/TI):
1. Read REG09
2. Write BATFET_DLY=1 (bit 3) -- delays disconnect so I2C completes
3. Write BATFET_DIS=1 | BATFET_DLY=1 (bits 5+3) -- last I2C write
The write happens after display turnOff but before board powerOff, so
I2C pull-ups on VDD3V3 are still alive. Board enters deep sleep, then
BATFET opens after tSM_DLY (~10-15s). Skipping the delay risks leaving
the BQ25896 I2C engine in an undefined state that can prevent wake on
USB-C plug-in (device soft-brick requiring battery disconnect).
REG09 bit map (confirmed from Linux kernel bq25890_charger.c):
Bit 7: FORCE_ICO
Bit 6: TMR2X_EN
Bit 5: BATFET_DIS (0x20) -- disconnect battery
Bit 4: JEITA_VSET
Bit 3: BATFET_DLY (0x08) -- delay before disconnect
Bit 2: BATFET_RST_EN (0x04) -- QON wake (not wired on T-Deck Pro)
Bit 1: PUMPX_UP
Bit 0: PUMPX_DN
Schematic confirms QON (pin 12) has R4 10K pull-up to REGN with no
user-accessible button -- USB-C is the only wake path from ship mode.
Guarded by #ifdef I2C_ADDR_BQ25896 so it compiles on all platforms
but only activates on boards with the charger (T-Deck Pro, T5S3).
Files changed:
UITask.h -- _full_poweroff, setFullPowerOff(), isHomeOnShutdownPage()
UITask.cpp -- shutdown page UI, input handling, BATFET write,
PRESS_LABEL cleanup, joystick removal
main.cpp -- 's' key gated on shutdown page (both handlers)
pelgraine