typec_plug_set_num_altmodes(9)

💅 typec_plug_set_num_altmodes(9) — the Kernel API Manual glow-up 🎀

okay so bestie, welcome to the typec_plug_set_num_altmodes page from the Kernel API Manual ✨ grab a boba, because we're about to tell the kernel how many alternate modes a plug has, and honestly? it's giving "small function, big responsibility" 💖

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✨ NAME ✨

typec_plug_set_num_altmodes — literally just sets the number of available plug altmodes 🦋

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🌸 SYNOPSIS 🌸

int typec_plug_set_num_altmodes (struct typec_plug *plug , int
       num_altmodes );

bestie it returns an int, it takes a struct typec_plug * and an int, and it's exactly as iconic as it looks 💅

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🫶 ARGUMENTS 🫶

• plug — the plug we're updating. the main character plug, if you will 👑
• num_altmodes — the number of altmodes we want to specify as available. yes, we choose the number. we hold the power 🔥

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💜 DESCRIPTION 💜

so this routine is what you use to report the number of alternate modes supported by the plug. lowkey important detail though: this value is *not* enforced in alternate mode registration routines. like, it's a report, not a bouncer at the club 💀 read that asterisk-star emphasis again, because the original is doing the most to make sure you noticed.

plug.num_altmodes is set to -1 on plug registration, denoting that a valid value has not been set for it yet. so if you see a -1 sitting there, that's the "no thoughts, head empty, value not set yet" state 🙈

Returns 0 on success or negative error number on failure. classic. slay when it's 0, sad girl hours when it's negative 😭

no cap: the -1 at plug registration is a denoting situation, meaning "not set yet" — it's not a real altmode count. don't be out here counting it as one 🎀

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🦋 SEE ALSO 🦋

the whole friend group showed up for this one, so here's everybody — same names, same (9), no substitutions 💖

• typec_altmode_update_active(9)
• typec_altmode2port(9)
• typec_altmode_set_ops(9)
• typec_unregister_altmode(9)
• typec_partner_set_usb_mode(9)
• typec_partner_set_identity(9)
• typec_partner_set_pd_revision(9)
• typec_partner_set_usb_power_delivery(9)
• typec_partner_set_num_altmodes(9)
• typec_partner_register_altmode(9)
• typec_partner_set_svdm_version(9)
• typec_partner_usb_power_delivery_register(9)
• typec_register_partner(9)
• typec_unregister_partner(9)
• typec_plug_register_altmode(9)
• typec_register_plug(9)
• typec_unregister_plug(9)
• typec_cable_get(9)
• typec_cable_put(9)
• typec_cable_is_active(9)
• typec_cable_altmode_unsupported(9)
• typec_cable_set_identity(9)
• typec_register_cable(9)
• typec_unregister_cable(9)
• typec_port_set_usb_mode(9)
• typec_port_set_usb_power_delivery(9)
• typec_set_data_role(9)
• typec_get_data_role(9)
• typec_set_pwr_role(9)
• typec_set_vconn_role(9)
• typec_set_pwr_opmode(9)
• typec_find_pwr_opmode(9)
• typec_find_orientation(9)
• typec_find_port_power_role(9)
• typec_find_power_role(9)
• typec_find_port_data_role(9)
• typec_set_orientation(9)
• typec_get_orientation(9)
• typec_set_mode(9)
• typec_get_negotiated_svdm_version(9)
• typec_get_cable_svdm_version(9)
• typec_cable_set_svdm_version(9)
• typec_get_drvdata(9)
• typec_port_register_altmode(9)
• typec_port_register_cable_ops(9)
• typec_register_port(9)
• typec_unregister_port(9)

also hanging out in the Kernel file ./drivers/usb/typec/class.c 🧚

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🌈 sign-off 🌈

that's the whole page, bestie, and you ate it up 👑 this little gem lives in ./drivers/usb/typec, dated October 2026, and it's giving "kernel docs but make it cute" 💖✨🎀 go forth and set those altmode numbers, periodt 🦋