__set_output_tf(9)

🎀 __set_output_tf(9) 🎀

okay so bestie, welcome to the Kernel API Manual — yes the actual Kernel API Manual, we're in the big leagues now 💅 — and today's main character is __set_output_tf, which (per its NAME, obviously) calculates the output transfer function based on expected input space. that's it, that's the whole glamorous job ✨

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✨ SYNOPSIS ✨

int __set_output_tf (struct dc_transfer_func *func , const struct
drm_color_lut *lut , uint32_t lut_size , bool has_rom );

four args, one int back, no cap 🫶

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🦋 ARGUMENTS 🦋

so like, here's the cast of characters, and every single one of them matters:

• func — the transfer function. this is the thing getting set up, the main character of the operation 👑
• lut — the lookup table that defines the color space. literally the whole palette, the vibe-definer 🌈
• lut_size — the size of the respective lut. yes, that lut, the one right above ⭐
• has_rom — if ROM can be used for hardcoded curve. a little yes/no flag, lowkey important 🙈

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💖 RETURN 💖

• 0 — in case of success. slay ✨
• -ENOMEM — if it fails 😭 (memory said no, not today)

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🌸 SEE ALSO 🌸

okay this list is long long, but we do not skip a single one, periodt 💅

The kernel file itself — ./drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c — that's the source, the origin story 🧚

and then the whole friend group:

• overview(9)
• amdgpu_dm_init_color_mod(9)
• __extract_blob_lut(9)
• __extract_blob_lut32(9)
• __is_lut_linear(9)
• __drm_lut_to_dc_gamma(9)
• __drm_lut32_to_dc_gamma(9)
• __drm_ctm_to_dc_matrix(9)
• __drm_ctm_3x4_to_dc_matrix(9)
• __set_legacy_tf(9)
• __set_output_tf_32(9)
• __set_input_tf(9)
• __set_input_tf_32(9)
• amdgpu_dm_verify_lut3d_size(9)
• amdgpu_dm_verify_lut_sizes(9)
• amdgpu_dm_check_crtc_color_mgmt(9)
• amdgpu_dm_update_crtc_color_mgmt(9)
• amdgpu_dm_update_plane_color_mgmt(9)

like. the way that's nineteen entries. obsessed, honestly 🔥

real talk though: if you're poking at colour management in amdgpu_dm, go read those — this page only covers the one function, no extra lore invented here 🫶

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mwah, that's the page 💜 this little love letter came from ./drivers/gpu/drm/amd/display/... and the manual's hanging out in October 2026 — and yes, it's still called __set_output_tf(9) at the bottom too, consistency icon 💅✨