dm_mst_test...wrong_dev_id(9)

💅 dm_mst_test...wrong_dev_id — Kernel API Manual, but make it make sense

okay so bestie, you found a KUnit test in the dm_mst test family and you want the tea ☕ — welcome, you're in the right doc. This is dm_mst_test...wrong_dev_id, straight out of the Kernel API Manual, and it's honestly a little icon of a test. Let's go 🫶

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✨ NAME ✨

dm_mst_test_needs_dsc_aux_workaround_wrong_dev_id — literally just testing that a workaround gets skipped when the device is the wrong device. no cap, that's the whole vibe check 💅

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🌸 SYNOPSIS 🌸

void dm_mst_test_needs_dsc_aux_workaround_wrong_dev_id (struct kunit *test );

like, it takes a KUnit test context and returns nothing. void. empty. giving minimalist main character energy ✨

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🎀 ARGUMENTS 🎀

• test — the KUnit test context 💖 it's the little scaffold KUnit hands you so the test can run and report back. love that for us.

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🦋 DESCRIPTION 🦋

okay so here's the plot: this test verifies that needs_dsc_aux_workaround returns false when the branch device ID does not match DP_BRANCH_DEVICE_ID_90CC24. 🚫🔥

that's it. that's the test. wrong dev id in → false out. the workaround stays home, the DSC AUX workaround does not get applied, and honestly? slay. correct behavior. periodt 💅

think of it as the negative case of the whole workaround saga — you're checking the code knows when to not do the thing, which is arguably harder than knowing when to do the thing. iykyk 🧚

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👑 SEE ALSO 👑

💜 The Kernel file itself

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

that's where the magic lives, go read it, it's giving source code realness ⭐

🌈 The rest of the dm_mst test fam (yes, all of them, i'm not skipping a single one)

• 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_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)

like, go read them all. or don't. i'm not your mom. but they're right there 🍓

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okay that's the whole page bestie, you're officially educated 💖 this cutie came from ./drivers/gpu/drm/amd/display/..., October 2026 edition, and it lives under the name dm_mst_test...wrong_dev_id(9) — go forth and run your KUnit tests, mwah 🎀💅✨