dm_test_shou...klight_index(9)

✨ NAME ✨

dm_test_should_create_sysfs_no_backlight_index — okay so this is a KUnit test that checks whether an eDP (that's embedded DisplayPort, for the uninitiated 💅) with no backlight index actually enables sysfs. Like, does the sysfs entry show up when there's no backlight index in the picture? That's the whole vibe check this test is running. 🦋

Also hey bestie, this page lives in the Kernel API Manual, section 9. Periodt.

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🌸 SYNOPSIS 🌸

void dm_test_should_create_sysfs_no_backlight_index(struct kunit *test);

Returns nothing (void), takes exactly one thing, and yes we're gonna talk about that one thing right now 👇

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🎀 ARGUMENTS 🎀

• test — the KUnit test context. That's it, that's the whole argument list. It's giving "minimalist icon" energy. 🫶

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🦋 SEE ALSO 🦋

💖 The kernel file

• Kernel file: ./drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c — go read the source if you want the full lore, iykyk.

⭐ The whole friend group (all section 9, all linked)

• dm_test_find_stream_with_link_returns_match(9)
• dm_test_find_stream_with_link_missing(9)
• dm_test_backlight_set_level_connector_off(9)
• dm_test_backlight_set_level_no_stream(9)
• dm_test_backlight_set_level_aux_programs_power_module(9)
• dm_test_backlight_set_level_pwm_programs_power_module(9)
• dm_test_backlight_set_level_reallows_idle(9)
• dm_test_backlight_update_status_no_stream(9)
• dm_test_backlight_get_level_pwm_success(9)
• dm_test_backlight_get_level_pwm_error(9)
• dm_test_backlight_get_level_aux_success(9)
• dm_test_backlight_get_level_aux_error(9)
• dm_test_backlight_get_brightness_uses_device_index(9)
• dm_test_register_backlight_device_negative_index(9)
• dm_test_register_backlight_device_success(9)
• dm_test_panel_power_savings_show_maps_disable_to_zero(9)
• dm_test_panel_power_savings_show_reports_level(9)
• dm_test_panel_power_savings_store_sets_disable(9)
• dm_test_panel_power_savings_store_forbidden(9)
• dm_test_panel_power_savings_store_rejects_invalid_text(9)
• dm_test_panel_power_savings_store_rejects_out_of_range(9)
• dm_test_backlight_device_index_matches_second(9)
• dm_test_backlight_device_index_missing_fallback(9)
• dm_test_backlight_caps_valid_short_circuit(9)
• dm_test_backlight_caps_aux_support_noop(9)
• dm_test_backlight_caps_non_aux_sets_defaults(9)
• dm_test_brightness_range_null_caps(9)
• dm_test_brightness_range_pwm(9)
• dm_test_brightness_range_aux(9)
• dm_test_brightness_to_user_null_caps(9)
• dm_test_brightness_to_user_below_min(9)
• dm_test_brightness_to_user_at_max(9)
• dm_test_brightness_to_user_at_min(9)
• dm_test_brightness_to_user_midpoint_pwm(9)
• dm_test_brightness_from_user_null_caps(9)
• dm_test_brightness_from_user_zero(9)
• dm_test_brightness_from_user_max(9)
• dm_test_brightness_from_user_aux(9)
• dm_test_custom_brightness_no_data_points(9)
• dm_test_custom_brightness_debug_mask_disables(9)
• dm_test_custom_brightness_exact_match(9)
• dm_test_custom_brightness_below_first(9)
• dm_test_custom_brightness_interpolation(9)
• dm_test_custom_brightness_above_last(9)
• dm_test_custom_brightness_single_data_point(9)
• dm_test_custom_brightness_lower_lum_zero(9)
• dm_test_brightness_to_user_above_max(9)
• dm_test_brightness_from_user_midrange(9)
• dm_test_brightness_from_user_with_curve(9)
• dm_test_brightness_range_zero_signals(9)
• dm_test_backlight_fill_props_ac_linear(9)
• dm_test_backlight_fill_props_dc_nonlinear(9)
• dm_test_backlight_fill_props_default_range(9)
• dm_test_update_connector_ext_caps_negative_bl_idx(9)
• dm_test_update_connector_ext_caps_non_edp(9)
• dm_test_update_connector_ext_caps_oled_defaults(9)
• dm_test_update_connector_ext_caps_luminance_values(9)
• dm_test_update_connector_ext_caps_force_aux(9)
• dm_test_update_connector_ext_caps_force_pwm(9)
• dm_test_should_create_sysfs_abm_forced(9)
• dm_test_should_create_sysfs_non_edp(9)
• dm_test_should_create_sysfs_oled_no_cacp(9)
• dm_test_should_create_sysfs_oled_cacp(9)
• dm_test_should_create_sysfs_lcd_panel(9)
• dm_test_setup_backlight_device_non_edp(9)
• dm_test_setup_backlight_device_connection_none(9)
• dm_test_setup_backlight_device_max_edps(9)
• dm_test_setup_backlight_device_oled_success(9)
• dm_test_setup_backlight_device_attaches_abm_property(9)

ngl that's a lot of tests and every single one of them made the list, no skips, no cuts. We support the whole squad. 👑

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okay that's the whole page bestie, ily, go run your KUnit tests 💜

sign-off era: this was dm_test_shou...klight_index(9) from the Kernel API Manual, sourced from ./drivers/gpu/drm/amd/display/..., dated October 2026. Slay. 🎀✨