drm_dp_tunne..._required_bw(9)

💅 drm_dp_tunne..._required_bw(9) — like, the kernel API manual, section 9, bestie ✨

okay so real talk, this is a page from the kernel API manual (9), and yes the title got chopped to drm_dp_tunne..._required_bw(9) because apparently even manpage headers have a character limit and honestly? relatable. the actual star of the show is drm_dp_tunnel_atomic_get_required_bw and she is serving 🎀

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🌸 NAME 🌸

drm_dp_tunnel_atomic_get_required_bw — get the BW required by a DP tunnel. that's it, that's the whole vibe. she tells you how much bandwidth the tunnel needs, no cap 💖

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✨ SYNOPSIS ✨

int drm_dp_tunnel_atomic_get_required_bw (const struct
drm_dp_tunnel_state *tunnel_state );

like, you hand her a tunnel state and she hands you back an int with the required BW. simple. iconic. periodt 🫶

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🦋 ARGUMENTS 🦋

• tunnel_state — the atomic state of the tunnel you're querying 👀 that's the one you're asking about, bestie. const struct drm_dp_tunnel_state *, so she's just reading, not touching. respectful queen 💅

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🎀 DESCRIPTION 🎀

so what she does is calculate the BW required by a tunnel — and the way she does it is by adding up the required BW of all the streams in the tunnel. every single one. no skipping, no shortcuts, we love a thorough main character 🌈

then she returns the total BW required by the tunnel. that's the whole function. lowkey elegant, highkey useful ✨

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🔥 SEE ALSO 🔥

the kernel file lives at ./drivers/gpu/drm/display/drm_dp_tunnel.c — go say hi to her 🧚

and here's the whole friend group, fr fr, every single one:

• drm_dp_tunnel_get(9)
• drm_dp_tunnel_put(9)
• drm_dp_tunnel_set_io_error(9)
• drm_dp_tunnel_detect(9)
• drm_dp_tunnel_destroy(9)
• drm_dp_tunnel_enable_bw_alloc(9)
• drm_dp_tunnel_disable_bw_alloc(9)
• drm_dp_tunnel_bw_alloc_is_enabled(9)
• drm_dp_tunnel_pr_optimization_supported(9)
• drm_dp_tunnel_alloc_bw(9)
• drm_dp_tunnel_get_allocated_bw(9)
• drm_dp_tunnel_update_state(9)
• drm_dp_tunnel_128b132b_supported(9)
• drm_dp_tunnel_128b132b_lane0_mapping_supported(9)
• drm_dp_tunnel_128b132b_dprx_rates(9)
• drm_dp_tunnel_max_dprx_rate(9)
• drm_dp_tunnel_max_dprx_lane_count(9)
• drm_dp_tunnel_available_bw(9)
• drm_dp_tunnel_atomic_get_state(9)
• drm_dp_tunnel_atomic_get_old_state(9)
• drm_dp_tunnel_atomic_get_new_state(9)
• drm_dp_tunnel_atomic_set_stream_bw(9)
• drm_dp_tunnel_atomic_get_group_streams_in_state(9)
• drm_dp_tunnel_atomic_check_stream_bws(9)
• drm_dp_tunnel_mgr_create(9)
• drm_dp_tunnel_mgr_destroy(9)

go read all of them. i'll wait. 💜

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ngl, the header is literally abbreviated to drm_dp_tunne..._required_bw(9) — that's not a typo on my end, that's just how the page comes, and honestly it's giving "username truncated by the app" energy 😭

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okay bye bestie, this page came from ./drivers/gpu/drm/display and it's dated October 2026, part of the Kernel API Manual section 9 — slay, see you in the next manpage 💖🎀🦋