STRUCT V4L2_SUBDEV_FRAME_INTERVAL(9)

💅 struct v4l2_subdev_frame_interval(9) 💅

okay so bestie, welcome to the Kernel API Manual ✨ — yes, the actual kernel API, and yes, this page is about a lil struct called v4l2_subdev_frame_interval. It's giving pad-level frame rate realness 🎀 and honestly? she's iconic.

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🌸 NAME 🌸

struct v4l2_subdev_frame_interval — Pad-level frame rate 💫

Like, literally just that. Pad-level frame rate. That's the whole vibe check 🦋

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✨ SYNOPSIS ✨

struct v4l2_subdev_frame_interval {
    __u32 pad;
    struct v4l2_fract interval;
    __u32 stream;
    __u32 which;
    __u32 reserved[7];
 };

copy this exactly, no cap, do not touch the semicolons, do not "fix" the spacing 🙈

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🫶 Members 🫶

hh okay let's go through every single one of these, no skipping, we don't do that here 💖

• pad — the pad number, as reported by the media API 👑 (yes, that media API, you know the one)
• interval — the frame interval, in seconds ⏱️ (lowkey the whole point of this struct ngl)
• stream — the stream number, defined in subdev routing 🌈
• which — the interval type, straight from enum v4l2_subdev_format_whence 🧚
• reserved — drivers and applications must zero this array 💀

🚨 okay this one matters, bestie — reserved genuinely has to be zeroed by drivers and applications. Both. Everybody. Zero it. That's not a suggestion, that's the rules, fr fr 🫡

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👑 SEE ALSO 👑

Kernel file ./include/uapi/linux/v4l2-subdev.h — plus enum v4l2_subdev_format_whence(9) 🌟 and the whole bestie squad:

• struct v4l2_subdev_format(9)
• struct v4l2_subdev_crop(9)
• struct v4l2_subdev_mbus_code_enum(9)
• struct v4l2_subdev_frame_size_enum(9)
• struct v4l2_subdev_frame_interval_enum(9)
• struct v4l2_subdev_selection(9)
• struct v4l2_subdev_capability(9)
• struct v4l2_subdev_route(9)
• struct v4l2_subdev_routing(9)
• struct v4l2_subdev_client_capability(9)

like, the full group chat 😭💕 read them all, iykyk

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aaaand that's the page!! 🎀 source lives at ./include/uapi/linux, dated October 2026 ⭐ — mwah, sending you the biggest kiss, go forth and set your frame intervals responsibly 💜🦋🌸