typec_cable_altmode_vdm(9)

💅 typec_cable_altmode_vdm(9) 💅

okay bestie, welcome to the typec_cable_altmode_vdm page from the Kernel API Manual — yes it's a kernel function, no it's not scary, i promise 🫶

🌸 NAME 🌸

typec_cable_altmode_vdm — the glow-up function that sends Vendor Defined Messages (VDM) between the cable plug and the port ✨

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🔥 SYNOPSIS 🔥

int typec_cable_altmode_vdm (struct typec_altmode *adev , enum
typec_plug_index sop , const u32 header , const u32 *vdo , int count );

like literally that's the whole signature, no cap 💀

🎀 ARGUMENTS 🎀

• adev — the Alternate mode handle 💖 your main character pointer
• sop — Cable plug target for VDM 🦋 (type is enum typec_plug_index, slay)
• header — the VDM Header 👑
• vdo — Array of Vendor Defined Data Objects ⭐ (it's a const u32 *, so it's giving read-only energy)
• count — Number of Data Objects 🍓

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✨ DESCRIPTION ✨

so here's the vibe: the alternate mode drivers use this function for SVID specific communication with the cable plugs 💅 yeah, SVID specific, that's the whole point.

and the port drivers? they use it to deliver the Structured VDMs received from the cable plugs to the alternate mode drivers 📬 like a lil delivery service but for structured vendor defined messages, iykyk.

ngl that's it — two jobs, one function, iconic behavior 🧚

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🌈 SEE ALSO 🌈

• the kernel file ./drivers/usb/typec/bus.c 📁 (yes, that exact path, go look)
• typec_altmode_notify(9)
• typec_altmode_enter(9)
• typec_altmode_exit(9)
• typec_altmode_attention(9)
• typec_altmode_vdm(9)
• typec_cable_altmode_enter(9)
• typec_cable_altmode_exit(9)
• typec_altmode_get_plug(9)
• typec_altmode_put_plug(9)
• typec_match_altmode(9)

all the siblings fr fr, go read them too 🔥

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and that's the page bestie!! 💜 brought to you by ./drivers/usb/typec, dated October 2026 — periodt, go forth and send those VDMs 🌸🎀