dm_mst_test_...around_match(9)

💅 dm_mst_test_needs_dsc_aux_workaround_match — Kernel API Manual, bestie edition ✨

okay so real talk, this is a page from the Kernel API Manual (the 9 section, kernel internals, very demure, very mindful) and it's all about one tiny KUnit test that goes by the name dm_mst_test_needs_dsc_aux_workaround_match. she's niche. she's specific. she slays. let's get into it 🎀

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✨ NAME ✨

dm_mst_test_needs_dsc_aux_workaround_match — literally just vibes-checking that the workaround triggers for the matching device 💖

like fr, that's the whole job. "test workaround triggers for matching device." no notes. iconic.

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🌸 SYNOPSIS 🌸

void dm_mst_test_needs_dsc_aux_workaround_match (struct kunit *test );

that's it. that's the whole signature. she takes one thing and returns void (she gives nothing back, main character energy honestly 💅).

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🦋 ARGUMENTS 🦋

• test — the KUnit test context 💜 this is the little test-world she lives inside, like her own personal group chat

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🎀 DESCRIPTION 🎀

okay so here's the tea, bestie ☕ this test verifies that needs_dsc_aux_workaround returns true when the link has:

• the specific branch device ID 👑
• DPCD rev 1.4 ✨
• sink count >= 2 🌈

all three at once, and the function should pop off and say "yes, true, workaround needed." and this test is the one that confirms it actually does that. no cap. it's giving "everything lines up exactly right and we check it." periodt 🫶

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🌟 SEE ALSO 🌟

• Kernel file — ./drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_mst_types_test.c (go read it, iykyk 🧚)

and the whole extended friend group of sibling tests, because they all roll together:

• 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_no_aux(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)

that's a LOT of siblings 😭 but every single one of them matters, don't skip a single name okay? they're all family 💖

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okay that's the whole page, bestie 🫶 this one comes from ./drivers/gpu/drm/amd/display/... — that's the source/version stamp — and it's dated October 2026 ⭐ so yeah, future-coded, we love that for us. and the header up top was dm_mst_test_...around_match(9) from the Kernel API Manual, now you know the full picture 💜 go forth and test your workarounds, mwah 💋✨