ENUM AUX_CHANNEL_TYPE(9)

💅 enum aux_channel_type(9) — the Kernel API Manual moment 🎀

okay so bestie, welcome to the Kernel API Manual entry for enum aux_channel_type, which is literally just the DP AUX channel type listing. that's it. that's the whole vibe. she's a little enum with two (2) moods and zero (0) descriptions, and honestly? iconic for that. ✨

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🦋 NAME 🦋

enum aux_channel_type — the DP AUX channel type listing, no cap. it exists purely to name the channel types, nothing more, and we respect her for it. 👑

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🌸 SYNOPSIS 🌸

here's the whole girl, in her full form, copied exactly so you can screenshot it:

enum aux_channel_type {
    AUX_CHANNEL_LEGACY_DDC ,
    AUX_CHANNEL_DPIA

};

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⭐ CONSTANTS ⭐

okay so this is where it gets funny. the source doc gives us the two constants and then just… leaves. both of them are marked -- undescribed --, like the documentation writer said "you're on your own bestie" and closed the laptop. 💀 i'm not gonna invent lore for them — that would be lying — so here's exactly what the source says:

• AUX_CHANNEL_LEGACY_DDC — the doc literally says -- undescribed --. that's the entire description. main character energy of a constant that refuses to introduce herself. 🙈
• AUX_CHANNEL_DPIA — also -- undescribed --. equally mysterious, equally unbothered. ✨

ngl if you need to know what these actually do, go read the header — this manpage is not gonna be the one to tell you, and i'm not about to make stuff up. 🫶

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🌈 SEE ALSO 🌈

bestie. sit down. this is the biggest friend group in the whole kernel. the source is the Kernel file ./drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h, and it links out to literally everyone it has ever met. every single one, in order:

• union dmub_addr(9)
• struct dmub_cursor_offload_pipe_data_dcn30_v1(9)
• struct dmub_cursor_offload_pipe_data_dcn401_v1(9)
• struct dmub_cursor_offload_pipe_data_dcn60_v1(9)
• struct dmub_cursor_offload_pipe_data_v1(9)
• struct dmub_cursor_offload_payload_data_v1(9)
• struct dmub_cursor_offload_stream_v1(9)
• struct dmub_cursor_offload_v1(9)
• union dmub_fw_meta_feature_bits(9)
• struct dmub_fw_meta_info(9)
• union dmub_fw_meta(9)
• struct dmcub_trace_buf_entry(9)
• union dmub_fw_boot_status(9)
• enum dmub_fw_boot_status_bit(9)
• enum dmub_cursor_offload_comand_type(9)
• union dmub_fw_boot_options(9)
• enum dmub_shared_state_feature_id(9)
• struct dmub_shared_state_ips_fw(9)
• struct dmub_shared_state_ips_driver(9)
• struct dmub_shared_state_cursor_offload_v1(9)
• struct dmub_shared_state_feature_block(9)
• union dmub_gpint_data_register(9)
• enum dmub_out_cmd_type(9)
• struct dmub_cmd_header(9)
• struct dmub_rb_cmd_common(9)
• struct dmub_cmd_PLAT_54186_wa(9)
• struct dmub_rb_cmd_PLAT_54186_wa(9)
• enum dmub_cmd_mall_type(9)
• struct dmub_rb_cmd_mall(9)
• enum dmub_cmd_cab_type(9)
• struct dmub_rb_cmd_cab_for_ss(9)
• enum dmub_fams2_allow_delay_check_mode(9)
• enum dmub_cmd_idle_opt_type(9)
• struct dmub_rb_cmd_idle_opt_dcn_restore(9)
• struct dmub_dcn_notify_idle_cntl_data(9)
• struct dmub_rb_cmd_idle_opt_dcn_notify_idle(9)
• enum dmub_idle_opt_dc_power_state(9)
• struct dmub_idle_opt_set_dc_power_state_data(9)
• struct dmub_rb_cmd_idle_opt_set_dc_power_state(9)
• struct dmub_clocks(9)
• enum dmub_cmd_clk_mgr_type(9)
• struct dmub_rb_cmd_clk_mgr_notify_clocks(9)
• struct dmub_cmd_digx_encoder_control_data(9)
• struct dmub_rb_cmd_digx_encoder_control(9)
• struct dmub_cmd_set_pixel_clock_data(9)
• struct dmub_cmd_enable_disp_power_gating_data(9)
• struct dmub_rb_cmd_enable_disp_power_gating(9)
• struct dmub_dig_transmitter_control_data_v1_7(9)
• union dmub_cmd_dig1_transmitter_control_data(9)
• struct dmub_rb_cmd_dig1_transmitter_control(9)
• struct dmub_rb_cmd_domain_control_data(9)
• struct dmub_rb_cmd_domain_control(9)
• struct dmub_rb_cmd_dpphy_init(9)
• enum dp_aux_request_action(9)
• enum aux_return_code_type(9)
• struct aux_transaction_parameters(9)
• struct dmub_rb_cmd_hpd_sense_notify(9)
• enum dmub_phy_fsm_state(9)
• enum dmub_abm_ace_curve_type(9)
• enum dmub_abm_histogram_type(9)
• enum dmub_cmd_panel_cntl_type(9)
• struct dmub_cmd_panel_cntl_data(9)
• struct dmub_rb_cmd_panel_cntl(9)
• struct dmub_cmd_cable_id_input(9)
• struct dmub_cmd_cursor_offload_init_data(9)
• struct dmub_rb_cmd_cursor_offload_init(9)
• struct dmub_cmd_cursor_offload_stream_data(9)
• struct dmub_rb_cmd_cursor_offload_stream_cntl(9)
• union dmub_rb_cmd(9)
• union dmub_rb_out_cmd(9)
• struct dmub_rb_init_params(9)
• struct dmub_rb(9)

like i said. biggest friend group. iykyk. 🔥

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and that's the whole page, bestie — short, sweet, and fully honest about the -- undescribed -- situation. this cutie came out of ./drivers/gpu/drm/amd/display/... with an October 2026 date stamp, so go forth and read the header file, periodt. 💖🎀🦋