STRUCT V4L2_SUBDEV_SELECTION(9)

✨ struct v4l2_subdev_selection(9) ✨

okay bestie, welcome to the Kernel API Manual 💖 this one's about struct v4l2_subdev_selection(9) and it's genuinely so useful, i promise. sit down, grab a lil drink 🍓

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🌸 NAME 🌸

struct v4l2_subdev_selection — selection info. that's it. that's the whole vibe. it's a struct that holds selection info 🎀

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🦋 SYNOPSIS 🦋

struct v4l2_subdev_selection {
    __u32 which;
    __u32 pad;
    __u32 target;
    __u32 flags;
    struct v4l2_rect r;
    __u32 stream;
    __u32 reserved[7];
 };

like look at her. she's gorgeous. ten out of ten struct 💅

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💅 Members 💅

• which — either V4L2_SUBDEV_FORMAT_ACTIVE or V4L2_SUBDEV_FORMAT_TRY. yes those are the only two options, pick one, no cap 🫶
• pad — the pad number, exactly as reported by the media API. don't make one up, use the real one bestie ✨
• target — the selection target. this is what picks which of the possible rectangles you mean. it's defined in v4l2-common.h and the family is V4L2_SEL_TGT_* 🎯
• flags — the constraint flags, also defined in v4l2-common.h, and these ones are V4L2_SEL_FLAG_* 🚩
• r — the coordinates of the selection window. like, where the box lives 📐
• stream — the stream number, defined in subdev routing 🌊
• reserved — for future use, so set it to zero for now. do NOT get cute with it, i'm serious, leave it alone 🙈

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🔥 Description 🔥

so here's the tea ☕ hardware may use multiple helper windows to process a video stream — like, more than one, it's a whole thing. this structure is the one that carries those selection areas back and forth between an application and a driver. it's literally the messenger 🧚

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⭐ SEE ALSO ⭐

• Kernel file ./include/uapi/linux/v4l2-subdev.h
• enum v4l2_subdev_format_whence(9)
• 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(9)
• struct v4l2_subdev_frame_interval_enum(9)
• struct v4l2_subdev_capability(9)
• struct v4l2_subdev_route(9)
• struct v4l2_subdev_routing(9)
• struct v4l2_subdev_client_capability(9)

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okay that's the whole page, you ate that ngl 👑 go read the header file next, iykyk

and that's a wrap bestie!! 🌈 this came from ./include/uapi/linux, dated October 2026, and it's filed under struct v4l2_...ev_selection(9) — mwah, love u, bye 💜🎀