__v4l2_device_call_subdevs(9)

📦 version 7.3.1, in nixpkgs unstable

💅 __v4l2_device_call_subdevs (9) — Kernel API Manual, bestie edition 🎀

okay so real talk, bestie: this one lives in the Kernel API Manual, and it's genuinely one of those "the name is scary but the vibe is simple" situations. Let me put you on. 🫶

✨ NAME ✨

__v4l2_device_call_subdevs — calls the specified operation for all subdevs matching the condition. That's it, that's the whole thing. It's giving "group text blast, but only to the people who match the filter." 📣

🌸 SYNOPSIS 🌸

__v4l2_device_call_subdevs (v4l2_dev , cond , o , f , args... );

yes, that's the signature. five-ish slots and then a little ... at the end doing the most. 💅

💖 ARGUMENTS 💖

  • v4l2_dev — the struct v4l2_device that owns the sub-devices you're about to iterate over. like, it's the group chat admin. the subdevs belong to it. 🫡
  • cond — the condition to be match(ed). this is your vibe check: only subdevs that pass it get the call. ⭐
  • o — the name of the element in struct v4l2_subdev_ops that contains f. lowkey important: each element in there groups a whole set of operation functions, so you're pointing at the drawer, and f is the thing in that drawer. 🗂️
  • f — the operation function that will actually be called when cond matches. ngl, these operation functions are all defined in groups, sorted according to each element of struct v4l2_subdev_ops. so yes, the grouping is real and it matters. 😌
  • args — the arguments for f. the little ... snack pack. 🍓

🦋 DESCRIPTION 🦋

Ignore any errors. literally just — ignore them. not me, not you, the code. errors? don't know her. 🙈

bestie, that's not a vibe suggestion, that's the documented behaviour: any errors get ignored. no cap. 🫶

🌈 NOTE 🌈

subdevs cannot be added or deleted while walking the subdevs list. like, do NOT rearrange the group chat while the broadcast is running. that's the whole warning. respect the list. 💀

👑 SEE ALSO 👑

Kernel file ./include/media/v4l2-device.h, and honestly? the whole extended family. icons only:

anyway that's the whole page, you ate that 💅✨

sign-off time, bestie: this little masterpiece is filed under ./include/media 🎀 dated October 2026 🗓️ and answers to the name __v4l2_device_call_subdevs(9) 💜 mwah 🫶🌸

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