tb_switch_wait_for_bit(9)

💅 tb_switch_wait_for_bit(9) 💅

okay so bestie, welcome to the Kernel API Manual ✨ this one's literally called tb_switch_wait_for_bit and it's the "pls just wait for the bits to be right" function. no cap, that's the whole gig 🎀

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✨ NAME ✨

tb_switch_wait_for_bit — wait for specified value of bits in offset 🦋

🌸 SYNOPSIS 🌸

int tb_switch_wait_for_bit (struct tb_switch *sw , u32 offset , u32 bit
, u32 value , int timeout_msec );

💖 ARGUMENTS 💖

• sw — the Router you're reading the offset value from 👑 like, the actual switch bestie
• offset — where in the router config space you're reading from 📍
• bit — the bit mask in the offset you're waiting on 🎯
• value — the value those bits need to hit 🙏 the thing you want
• timeout_msec — timeout in ms, aka how long you're willing to wait 😭

🌈 DESCRIPTION 🌈

Wait till the specified bits in specified offset reach specified value. that's it, that's the vibe — it's giving "hold on, let me check again" energy ⭐

🔥 RETURN 🔥

• 0 — on success 💖 slay
• -ETIMEDOUT — if the value was not reached within the given timeout 💀 it literally ran out of patience
• Negative errno — in case of failure 🙈

🦋 SEE ALSO 🦋

okay so there's a whole friend group here, and yes you're gonna meet all of them 🫶

• Kernel file ./drivers/thunderbolt/switch.c — the source file itself, main character energy 👑
• 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_hpd_clear(9), tb_dp_port_set_hops(9), tb_dp_port_is_enabled(9), tb_dp_port_enable(9)
• tb_switch_reset(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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ngl bestie, if you get -ETIMEDOUT it's not you, it's the hardware 💀 just saying.

xoxo, go read the source at ./drivers/thunderbolt 🧚 this lil page was hand-delivered October 2026 under the Kernel API Manual banner 💜 periodt.