dm_mst_test_...tream_no_aux(9)

💅 dm_mst_test_retrieve_downstream_no_aux — Kernel API Manual ✨

okay so bestie, welcome to the manual page for dm_mst_test_retrieve_downstream_no_aux(9) — yes that's the real full name, the page header had to abbreviate it as dm_mst_test_...tream_no_aux(9) because it's giving "long title energy" and honestly? iconic of it. this is the Kernel API Manual, and we're about to get into it 🎀

✨ NAME ✨

dm_mst_test_retrieve_downstream_no_aux — literally just a test that checks retrieval bails out without AUX 💅

🌸 SYNOPSIS 🌸

void dm_mst_test_retrieve_downstream_no_aux (struct kunit *test );

🦋 ARGUMENTS 🦋

• test — the KUnit test context, bestie. that's it, that's the whole argument 🫶

💖 DESCRIPTION 💖

so here's the vibe check: this test verifies that retrieve_downstream_port_device returns false when the connector has no DSC AUX channel and therefore cannot read DPCD. no AUX channel, no DPCD read, and the function bails out — that's the whole point, no cap. it's a "the function says nope when it can't do the thing" test and we love a clean boundary case 🔥

👑 SEE ALSO 👑

the kernel file this lives in, in all its glory:

./drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_mst_types_test.c

and now the whole test squad, assembling like it's a group chat roll call 💀:

• dm_mst_test_needs_dsc_aux_workaround_match(9)
• dm_mst_test_needs_dsc_aux_workaround_rev12(9)
• dm_mst_test_needs_dsc_aux_workaround_wrong_dev_id(9)
• dm_mst_test_needs_dsc_aux_workaround_wrong_rev(9)
• dm_mst_test_needs_dsc_aux_workaround_low_sink_count(9)
• dm_mst_test_needs_dsc_aux_workaround_zero_sink_count(9)
• dm_mst_test_pbn_divider_null_link(9)
• dm_mst_test_pbn_divider_uses_link_bandwidth(9)
• dm_mst_test_reset_connector_setting(9)
• dm_mst_test_retrieve_downstream_present(9)
• dm_mst_test_retrieve_downstream_aux_error(9)
• dm_mst_test_retrieve_branch_no_parent(9)
• dm_mst_test_retrieve_branch_reads_oui(9)
• dm_mst_test_aux_result_success(9), dm_mst_test_aux_result_eio(9), dm_mst_test_aux_result_ebusy(9), dm_mst_test_aux_result_timeout(9)
• dm_mst_test_aux_transfer_native_read(9)
• dm_mst_test_aux_transfer_native_write(9)
• dm_mst_test_aux_transfer_partial_write(9)
• dm_mst_test_aux_transfer_error_result(9)
• dm_mst_test_aux_transfer_hpd_discon_quirk(9)
• dm_mst_test_aux_transfer_non_ack_reply(9)
• dm_mst_test_fill_payload_flags_native_write(9)
• dm_mst_test_fill_payload_flags_native_read(9)
• dm_mst_test_fill_payload_flags_i2c_read_mot(9)
• dm_mst_test_fill_payload_flags_write_status(9)
• dm_mst_test_msg_ready_mask(9), dm_mst_test_select_esi_dpcd_legacy(9), dm_mst_test_select_esi_dpcd_esi(9)
• dm_mst_test_sideband_msg_ready_no_ready_bits(9)
• dm_mst_test_sideband_msg_ready_read_error(9)
• dm_mst_test_sideband_msg_ready_without_mst_state(9)
• dm_mst_test_down_rep_msg_ready_wrapper(9)
• dm_mst_test_initialize_dp_connector_edp(9)
• dm_mst_test_initialize_dp_connector_mst(9)
• dm_mst_test_atomic_best_encoder(9)
• dm_mst_test_create_fake_mst_encoders(9)
• dm_mst_test_atomic_check_no_old_crtc(9)
• dm_mst_test_detect_unregistered(9)
• dm_mst_test_fp_guarded_public_stubs(9)

and that's the page!! 🧚 before you go: this one came from ./drivers/gpu/drm/amd/display/..., dated October 2026, and it's the dm_mst_test_...tream_no_aux(9) page, slay. go read the other tests, they're all linked above, iykyk 💜🎀