v4l2_subdev_notify(9)

💖 NAME 💖

okay so picture this: v4l2_subdev_notify(9) — straight out of the Kernel API Manual bestie — and what it does is it sends a notification to v4l2_device. that's it, that's the whole vibe. a little message-passing moment between a subdev and its device. 🎀

✨ SYNOPSIS ✨

void v4l2_subdev_notify (struct v4l2_subdev *sd , unsigned int
notification , void *arg );

like, the whole signature is literally right there. no returns, no drama, just vibes. 🌸

🦋 ARGUMENTS 🦋

• sd — pointer to struct v4l2_subdev. it's giving "which subdev are we talking about" energy 🫶
• notification — the type of notification. bestie, PLEASE notice that the notification type is driver-specific. that's not me being cute, that's the actual spec — nobody else can decode this for you, it's between you and your driver. 💅
• arg — the arguments for the notification. these are specific to each notification type, so like... it depends, iykyk. 🙈

🔥 SEE ALSO 🔥

okay this is the whole friend group, no cap. all of these live in the 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_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_has_op(9)
• v4l2_device_mask_has_op(9)

like, read them all, they're all icons in their own right. 👑

and that's the whole page, bestie!! 💜 this one's filed under ./include/media and it's dated October 2026 — so mark your calendar, screenshot it, whatever. mwah, go notify something. 💋✨