STRUCT FF_CONSTANT_EFFECT(9)

💅 struct ff_constant_effect(9) — like, the whole glow-up ✨

okay bestie, welcome to the Kernel API Manual page for struct ff_constant_effect 🎀 this is the little struct that defines parameters of a constant force-feedback effect — yes, the "just hold it steady, babe" of the force-feedback world. no cap, she's simple and she serves. 🦋

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🌸 NAME 🌸

struct ff_constant_effect — literally the struct that defines parameters of a constant force-feedback effect. that's the whole vibe. periodt. 💅

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✨ SYNOPSIS ✨

struct ff_constant_effect {
    __s16 level;
    struct ff_envelope envelope;
};

look at her. two members. zero drama. main character energy fr fr 🔥

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🫶 Members 🫶

• level — the strength of the effect; and yes, it may be negative 😭 she can push either way, icon behaviour. __s16, so signed, so spicy both directions. 💜
• envelope — the envelope data, bestie 🎀 it's a struct ff_envelope, and it's doing the whole "how does this effect shape itself over time" thing. iykyk. 🌸

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👑 SEE ALSO 👑

like, go read these next, you'll be obsessed ⭐

Kernel file ./include/uapi/linux/input.h, plus:

• struct input_absinfo(9)
• struct input_keymap_entry(9)
• EVIOCGMTSLOTS(9)
• EVIOCGMASK(9)
• EVIOCSMASK(9)
• struct ff_replay(9)
• struct ff_trigger(9)
• struct ff_envelope(9)
• struct ff_ramp_effect(9)
• struct ff_condition_effect(9)
• struct ff_periodic_effect(9)
• struct ff_rumble_effect(9)
• struct ff_haptic_effect(9)
• struct ff_effect(9)

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no warnings here bestie, this one's a clean little struct — just remember level is actually signed, so negative values are valid, not a glitch 🙈

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and that's the page!! 🧚 from ./include/uapi/linux, dated October 2026, mwah 💖 bye bestie, go make some haptics slay 💅✨