tb_dp_port_hpd_clear(9)

💅 tb_dp_port_hpd_clear — the kernel API manual, but make it make sense

okay so bestie, welcome to the tb_dp_port_hpd_clear(9) page from the Kernel API Manual ✨ this is the little helper that goes "hpd? not on my watch" for a DP IN port. let's get into it 🫶

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🌸 NAME 🌸

tb_dp_port_hpd_clear — Clear HPD from DP IN port

bestie it does exactly what it says on the tin, no cap 💅

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✨ SYNOPSIS ✨

int tb_dp_port_hpd_clear (struct tb_port *port );

that's the whole vibe check: takes a pointer to a struct tb_port, hands you back an int 🎀

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🦋 ARGUMENTS 🦋

• port — Port to clear HPD

like, the port. the one you're clearing HPD on. that's her 👑

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🔥 DESCRIPTION 🔥

so here's the tea ☕ if the DP IN port has HPD set, this function can be used to clear it.

that's it. that's the whole lore. if it's set, you clear it. iconic behavior, honestly 💜

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⭐ RETURN ⭐

• 0 on success 🎉
• negative errno otherwise 😭

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🌈 SEE ALSO 🌈

the friend group is HUGE and we love every single one of them, fr fr 💖 also worth peeking at the kernel file ./drivers/thunderbolt/switch.c if you wanna see the source of truth 👀

• tb_switch_nvm_read(9), tb_port_state(9), tb_wait_for_port(9), tb_port_add_nfc_credits(9), tb_port_clear_counter(9), tb_port_unlock(9)
• tb_port_enable(9), tb_port_disable(9), tb_port_reset(9), tb_port_alloc_in_hopid(9), tb_port_alloc_out_hopid(9), tb_port_release_in_hopid(9)
• tb_port_release_out_hopid(9), tb_next_port_on_path(9), tb_port_get_link_speed(9), tb_port_get_link_generation(9), tb_port_get_link_width(9), tb_port_width_supported(9)
• tb_port_set_link_width(9), tb_port_set_lane_bonding(9), tb_port_lane_bonding_enable(9), tb_port_lane_bonding_disable(9), tb_port_wait_for_link_width(9), tb_port_update_credits(9)
• tb_port_is_enabled(9), tb_usb3_port_is_enabled(9), tb_usb3_port_enable(9), tb_pci_port_is_enabled(9), tb_pci_port_enable(9)
• tb_dp_port_hpd_is_active(9), tb_dp_port_set_hops(9), tb_dp_port_is_enabled(9), tb_dp_port_enable(9)
• tb_switch_reset(9), tb_switch_wait_for_bit(9), tb_switch_alloc(9), tb_switch_alloc_safe_mode(9), tb_switch_configure(9), tb_switch_configuration_valid(9)
• tb_switch_lane_bonding_enable(9), tb_switch_lane_bonding_disable(9), tb_switch_set_link_width(9), tb_switch_configure_link(9), tb_switch_unconfigure_link(9)
• tb_switch_add(9), tb_switch_remove(9), tb_sw_set_unplugged(9), tb_switch_resume(9), tb_switch_suspend(9)
• tb_switch_query_dp_resource(9), tb_switch_alloc_dp_resource(9), tb_switch_dealloc_dp_resource(9), tb_switch_find_by_link_depth(9), tb_switch_find_by_uuid(9), tb_switch_find_by_route(9), tb_switch_find_port(9)
• tb_switch_pcie_l1_enable(9), tb_switch_xhci_connect(9), tb_switch_xhci_disconnect(9)

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🫶 quick reminder bestie: 0 means slay, negative errno means we're in our flop era and you should check what went wrong. no guessing, just read the return value 💀

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and that's the page!! brought to you by ./drivers/thunderbolt, dated October 2026, living in the Kernel API Manual 💖 bye bestie, go clear some HPD ✨🎀