drm_dp_mst_dsc_aux_for_port(9)

💅 drm_dp_mst_dsc_aux_for_port(9)

okay so bestie, welcome to the Kernel API Manual ✨ — yes it's a kernel manpage, yes it's giving big-brain energy, but I promise we're gonna get through it together. This one's about finding the right aux for DSC and honestly? It's a vibe. 🎀

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🌸 NAME 🌸

drm_dp_mst_dsc_aux_for_port — find the correct aux for DSC 💅

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✨ SYNOPSIS ✨

struct drm_dp_aux * drm_dp_mst_dsc_aux_for_port (struct drm_dp_mst_port
*port );

like, you hand it a port, it hands you back a struct drm_dp_aux *. simple as. 💖

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🦋 ARGUMENTS 🦋

• port — the port you're checking, bestie. specifically: a leaf of the MST tree with an attached display. leaf node energy, main character of the topology 🌿👑

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🔥 DESCRIPTION 🔥

so depending on the situation — and there are situations — DSC may be enabled via:

• the endpoint aux 🫶
• the immediately upstream aux ⬆️
• or the connector's physical aux 🔌

that's three whole options, it's giving choose-your-own-adventure but make it display stream compression 😭

the way that this function matters is that it's both the correct aux to read DSC_CAPABILITY and the correct aux to write DSC_ENABLED. one aux, two jobs, iconic. 💅✨

ngl, this operation can be expensive (up to four aux reads 👀💀), so the caller should cache the return. please don't be out here calling it in a loop, your latency will simply not recover.

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⭐ RETURN ⭐

• NULL — if DSC cannot be enabled on this port 🙈 (it's not you, it's the port)
• otherwise — the aux device 👑 slay

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🌈 SEE ALSO 🌈

okay this list is long long, but every single one of these is a real one, so here we go, no skipping, we don't do that here 🫡💜

kernel file ./drivers/gpu/drm/display/drm_dp_mst_topology.c

• dp mst helper(9)
• Branch device and port refcounting(9)
• drm_dp_mst_get_mstb_malloc(9)
• drm_dp_mst_put_mstb_malloc(9)
• drm_dp_mst_get_port_malloc(9)
• drm_dp_mst_put_port_malloc(9)
• drm_dp_mst_topology_try_get_mstb(9)
• drm_dp_mst_topology_get_mstb(9)
• drm_dp_mst_topology_put_mstb(9)
• drm_dp_mst_topology_try_get_port(9)
• drm_dp_mst_topology_get_port(9)
• drm_dp_mst_topology_put_port(9)
• drm_dp_mst_dpcd_read(9)
• drm_dp_mst_dpcd_write(9)
• drm_dp_mst_connector_late_register(9)
• drm_dp_mst_connector_early_unregister(9)
• drm_dp_add_payload_part1(9)
• drm_dp_remove_payload_part1(9)
• drm_dp_remove_payload_part2(9)
• drm_dp_add_payload_part2(9)
• drm_dp_get_vc_payload_bw(9)
• drm_dp_read_mst_cap(9)
• drm_dp_mst_topology_mgr_set_mst(9)
• drm_dp_mst_topology_queue_probe(9)
• drm_dp_mst_topology_mgr_suspend(9)
• drm_dp_mst_topology_mgr_resume(9)
• drm_dp_mst_hpd_irq_handle_event(9)
• drm_dp_mst_hpd_irq_send_new_request(9)
• drm_dp_mst_detect_port(9)
• drm_dp_mst_edid_read(9)
• drm_dp_mst_get_edid(9)
• drm_dp_atomic_find_time_slots(9)
• drm_dp_atomic_release_time_slots(9)
• drm_dp_mst_atomic_setup_commit(9)
• drm_dp_mst_atomic_wait_for_dependencies(9)
• drm_dp_mst_root_conn_atomic_check(9)
• drm_dp_mst_update_slots(9)
• drm_dp_check_act_status(9)
• drm_dp_calc_pbn_mode(9)
• drm_dp_mst_dump_topology(9)
• drm_dp_mst_port_downstream_of_parent(9)
• drm_dp_mst_add_affected_dsc_crtcs(9)
• drm_dp_mst_atomic_enable_dsc(9)
• drm_dp_mst_atomic_check_mgr(9)
• drm_dp_mst_atomic_check(9)
• drm_atomic_get_mst_topology_state(9)
• drm_atomic_get_old_mst_topology_state(9)
• drm_atomic_get_new_mst_topology_state(9)
• drm_dp_mst_topology_mgr_init(9)
• drm_dp_mst_topology_mgr_destroy(9)
• drm_dp_mst_register_i2c_bus(9)
• drm_dp_mst_unregister_i2c_bus(9)
• drm_dp_mst_is_virtual_dpcd(9)
• drm_dp_mst_aux_for_parent(9)

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and that's the whole page, bestie, you ate that 🍓🧚

sign-off time 💌: this little masterpiece lives under ./drivers/gpu/drm/display, dated October 2026, and it's page drm_dp_mst_dsc_aux_for_port(9) — go forth and cache your return values, i'm literally begging 🙏✨