bq257xx_exte...ower_changed(9)

📦 version 7.3.1, in nixpkgs unstable

💅 bq257xx_external_power_changed(9) — like, the Kernel API Manual page you actually wanna read

okay so bestie, you're in the Kernel API Manual and this is the page for bq257xx_external_power_changed(9). it's a handler. for external power changes. the whole vibe is "something got plugged in or unplugged, time to freak out (professionally)". let's go ✨

🌸 NAME 🌸

bq257xx_external_power_changed — Handler for external power change 🫶

🎀 SYNOPSIS 🎀

void bq257xx_external_power_changed (struct power_supply *psy );

like literally that's it. void return, one argument, no drama (well, a little drama, see below) 💅

🦋 ARGUMENTS 🦋

  • psy — Power supply data. that's the whole description, she's succinct, we respect it 👑

🌈 DESCRIPTION 🌈

okay so here's the tea, and it's actually important tea, not gossip tea ☕

When the external power going into the charger changes, this handler checks the USB type so it can be, y'know, reported. that's step one, that's the vibe check. 🔌

Then it updates the max input current and the max charging current to the value that got reported — but only if the thing is a USB PD charger. If it's not? default value, no cap, we move on. ✨

⚠️ and now the part you CANNOT skip, bestie, because this one bites: every single time a charger is removed, the max charge current register is erased. gone. wiped. 😭 so it must be set again each time the input changes — otherwise the device will not charge. not "might not". will not. set the register, or your battery stays at zero and you're stuck at 1% looking like a clown 💀

🔥 SEE ALSO 🔥

the whole friend group shows up for this one, so let's give them their moment 🫶

Kernel file ./drivers/power/supply/bq257xx_charger.c — that's the home base, the main character file:

and that's the page!! 🎀 written from ./drivers/power/supply, dated October 2026, and yeah, the header really does abbreviate it to bq257xx_exte...ower_changed(9) — she got cut off in the middle of her own name and honestly? iconic. slay, truncated queen 👑✨💖

📦 where this page comes from