v4l2_device_has_op(9)

💅 v4l2_device_has_op — straight outta the Kernel API Manual ✨

okay so bestie, picture this: you've got a whole squad of sub-devices and you just wanna know if any of them has a specific ops. that's it. that's the function. it checks if any subdev with matching grpid has a given ops. lowkey iconic, highkey useful 🫶

🌸 SYNOPSIS 🌸

v4l2_device_has_op (v4l2_dev , grpid , o , f );

literally just those four, no cap 💅

🎀 ARGUMENTS 🎀

• v4l2_dev — the struct v4l2_device that owns the sub-devices we're gonna iterate over. it's giving main character energy, it holds the whole squad 👑
• grpid — the struct v4l2_subdev->grp_id group ID we're matching against. and listen — pass 0 and it matches them all. periodt. 🌈
• o — the name of the element at struct v4l2_subdev_ops that contains f. each element over there groups together a set of operation functions, so think of it as picking which lil drawer the function lives in 🎀
• f — the operation function that will be called if cond matches. the operation functions are defined in groups, according to each element at struct v4l2_subdev_ops — so yeah, o and f are besties fr fr 💖

heads up bestie: keep o and f in sync — o is the name of the struct v4l2_subdev_ops element that actually contains f, and the ops are grouped up according to those elements. no mixing and matching 🙈

🦋 SEE ALSO 🦋

the whole friend group, in the order the manpage lists them — not me being thorough, it's just how it is 💀

• Kernel file ./include/media/v4l2-device.h struct v4l2_device(9)
• v4l2_device_get(9)
• v4l2_device_put(9)
• v4l2_device_register(9)
• v4l2_device_set_name(9)
• v4l2_device_disconnect(9)
• v4l2_device_unregister(9)
• v4l2_device_register_subdev(9)
• v4l2_device_unregister_subdev(9)
• __v4l2_device_register_subdev_nodes(9)
• v4l2_device_register_subdev_nodes(9)
• v4l2_device_register_ro_subdev_nodes(9)
• v4l2_subdev_notify(9)
• v4l2_device_supports_requests(9)
• v4l2_device_for_each_subdev(9)
• __v4l2_device_call_subdevs_p(9)
• __v4l2_device_call_subdevs(9)
• __v4l2_device_call_subdevs_until_err_p(9)
• __v4l2_device_call_subdevs_until_err(9)
• v4l2_device_call_all(9)
• v4l2_device_call_until_err(9)
• v4l2_device_mask_call_all(9)
• v4l2_device_mask_call_until_err(9)
• v4l2_device_mask_has_op(9)

and that's the whole page, bestie 🌈 this little gem lives in the ./include/media directory, and it's stamped October 2026 — that's the version-and-date situation, mwah 💜 go check if your subdev has the ops, slay, and drink some water. 🍓✨