pch_udc_pcd_vbus_draw(9)

📦 version 7.3.1, in nixpkgs unstable

💅 pch_udc_pcd_vbus_draw(9) — like, the whole vibe

okay bestie, so this page is from the Kernel API Manual, and it's literally all about pch_udc_pcd_vbus_draw. she's a little function with a big job and honestly? she ate. let's get into it 🫶

✨ NAME ✨

pch_udc_pcd_vbus_draw — so this API is used by gadget drivers during SET_CONFIGURATION calls to specify how much power the device can consume. that's it, that's the whole point of her existence, and she's serving 💖

🌸 SYNOPSIS 🌸

int pch_udc_pcd_vbus_draw (struct usb_gadget *gadget , unsigned int mA );

she takes two things and gives you back an int, no cap.

🎀 ARGUMENTS 🎀

  • gadget — Reference to the gadget driver. this is the main character she's talking to, lowkey important, don't forget her 🦋
  • mA — specifies the current limit in 2mA unit. read that again bestie, 2mA unit, not 1mA, not milliamp-per-milliamp. do the math accordingly ✨

🔥 DESCRIPTION 🔥

so this is the part where we talk about what she gives back, and it's giving return codes:

  • -EINVAL — If the gadget passed is NULL. yes, if you hand her nothing she's gonna be like "girl, no" and return this 🙈
  • -EOPNOTSUPP —

and that's… genuinely where the original page ends. like, mid-sentence, mid-thought, the manpage just stops. no notes, no further explanation, just -EOPNOTSUPP: and then vibes 💀 i'm not making anything up here, i'm reporting exactly what's on the page. the docs said "and for my next trick" and then clocked out. iconic behavior honestly.

👑 SEE ALSO 👑

okay this section is a whole friend group, it's giving "and here's everyone she knows." the kernel file is ./drivers/usb/gadget/udc/pch_udc.c and the extended fam is huge, buckle up 🎀

like i said. huge friend group. she knows everyone at this point, iykyk 💅

ngl the takeaway is: pass her a real gadget, pass mA in 2mA units, and if you pass NULL she WILL hit you with -EINVAL. and -EOPNOTSUPP is out here too, existing, unexplained, mysterious, main character energy 👑

and that's the page bestie!! 🌈 this was the pch_udc_pcd_vbus_draw(9) situation, straight outta ./drivers/usb/gadget/udc, dated October 2026. go forth, draw some vbus, and stay slay 💖✨🎀

📦 where this page comes from