host1x_syncp..._reservation(9)

💖 host1x_syncp..._reservation(9) — Kernel API Manual 💖

ok so bestie, you found the page for host1x_syncpt_release_vblank_reservation and honestly? it's a little one-trick pony but the trick is important. it lives in the Kernel API Manual, so grab a snack 🍓 and let's get into it.

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✨ NAME ✨

host1x_syncpt_release_vblank_reservation — make a VBLANK syncpoint available for allocation 🎀

like, you're freeing it back to the pool. giving it back to the people. main character energy for a syncpoint, honestly.

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🌸 SYNOPSIS 🌸

void host1x_syncpt_release_vblank_reservation (struct host1x_client *client , u32 syncpt_id );

it returns void, so no "did it work" situation — it just does the thing. no cap.

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🦋 ARGUMENTS 🦋

• client — the host1x bus client. your entry ticket, your credentials, the whole vibe check 🪪
• syncpt_id — the syncpoint ID you want to make available 👑 literally the number of the syncpoint you're setting free

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💅 DESCRIPTION 💅

okay so here's the tea ☕: this function makes the VBLANK<i> syncpoint available for allocation if it happened to get reserved back at initialization time. so somebody called dibs on it early, and now you're undoing that dibs. iconic.

the way that you're supposed to use this: the display driver should call it after it has made sure that any VBLANK increment programming configured by the boot chain has been disabled. 🫶

⚠️ read that again bestie — after. the order is not optional. get the boot chain's VBLANK increment programming disabled first, then release the reservation. don't be out here releasing early, that's not the vibe 😭

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🔥 SEE ALSO 🔥

kernel file: ./drivers/gpu/host1x/syncpt.c — that's where the whole syncpoint saga lives 📁

and the full friend group of syncpoint functions, all of them, no skipping:

• host1x_syncpt_alloc(9)
• host1x_syncpt_id(9)
• host1x_syncpt_incr_max(9)
• host1x_syncpt_incr(9)
• host1x_syncpt_wait(9)
• host1x_syncpt_request(9)
• host1x_syncpt_put(9)
• host1x_syncpt_read_max(9)
• host1x_syncpt_read_min(9)
• host1x_syncpt_read(9)
• host1x_syncpt_get_by_id(9)
• host1x_syncpt_get_by_id_noref(9)
• host1x_syncpt_get(9)
• host1x_syncpt_get_base(9)
• host1x_syncpt_base_id(9)

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and that's the whole page, bestie — go release that reservation 💜

source path: ./drivers/gpu/host1x · date: October 2026 · page: host1x_syncp..._reservation(9)

mwah 💋 stan the kernel, drink water, and remember: disable the boot chain's VBLANK increment programming before you call this. periodt. 🌈⭐