STRUCT FF_HAPTIC_EFFECT(9)

🎀 struct ff_haptic_effect(9) 🎀

okay so this is from the Kernel API Manual, bestie, and the whole page is about struct ff_haptic_effect(9) — literally the haptic-effect struct itself. no cap, it’s giving “small but mighty kernel paperwork” ✨

💅 NAME 💅

struct ff_haptic_effect — that’s it, that’s the NAME entry. just the struct name plus the lil dash. minimal, mysterious, iconic 🫶

✨ SYNOPSIS ✨

here’s the exact shape of the struct:

       struct ff_haptic_effect {
           __u16 hid_usage;
           __u16 vendor_id;
           __u8 vendor_waveform_page;
           __u16 intensity;
           __u16 repeat_count;
           __u16 retrigger_period;
        };

🌸 Members 🌸

okay so each member is doing its own little job, and here’s the rundown:

• hid_usage — hid_usage according to Haptics page (WAVEFORM_CLICK, etc.)
• vendor_id — the waveform vendor ID if hid_usage is in the vendor-defined range
• vendor_waveform_page — the vendor waveform page if hid_usage is in the vendor-defined range
• intensity — strength of the effect as percentage
• repeat_count — number of times to retrigger effect
• retrigger_period — time before effect is retriggered (in ms)

🦋 SEE ALSO 🦋

Kernel file ./include/uapi/linux/input.h is the one to peek at, and the whole squad is:

• 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_constant_effect(9)
• struct ff_ramp_effect(9)
• struct ff_condition_effect(9)
• struct ff_periodic_effect(9)
• struct ff_rumble_effect(9)
• struct ff_effect(9)

mwah 💋 source/version: ./include/uapi/linux · date: October 2026 · page: struct ff_haptic_effect(9). bye bestie, go read those kernel files 🎀