spi_unregister_controller(9)

🌸 NAME 🌸

spi_unregister_controller — bestie, this is the one that unregisters an SPI host or target controller 💅

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✨ SYNOPSIS ✨

void spi_unregister_controller (struct spi_controller *ctlr );

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🎀 ARGUMENTS 🎀

• ctlr — literally the controller being unregistered, that's the whole vibe 🦋

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💜 CONTEXT 💜

can sleep 😴 — yes queen, take your nap, this one's allowed to block.

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🔥 DESCRIPTION 🔥

okay so listen 👑: this call is used only by SPI controller drivers, which are the only ones directly touching chip registers. iykyk — if you're not a controller driver, this is not your moment, hands off the registers fr fr.

and this must be called from context that can sleep. not optional, not a suggestion, not "eh it'll probably be fine" — it has to be sleepable context, periodt 😭

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🌈 SEE ALSO 🌈

Kernel file ./drivers/spi/spi.c — plus the whole friend group right here 🫶

• __spi_register_driver(9)
• spi_alloc_device(9)
• spi_add_device(9)
• spi_new_device(9)
• spi_unregister_device(9)
• spi_register_board_info(9)
• spi_res_alloc(9)
• spi_res_free(9)
• spi_res_add(9)
• spi_res_release(9)
• spi_finalize_current_transfer(9)
• __spi_pump_messages(9)
• spi_pump_messages(9)
• spi_take_timestamp_pre(9)
• spi_take_timestamp_post(9)
• spi_set_thread_rt(9)
• spi_get_next_queued_message(9)
• spi_finalize_current_message(9)
• spi_queued_transfer(9)
• spi_flush_queue(9)
• of_register_spi_devices(9)
• spi_new_ancillary_device(9)
• devm_spi_new_ancillary_device(9)
• acpi_spi_count_resources(9)
• acpi_spi_device_alloc(9)
• spi_target_abort(9)
• __spi_alloc_controller(9)
• __devm_spi_alloc_controller(9)
• spi_get_gpio_descs(9)
• spi_register_controller(9)
• devm_spi_register_controller(9)
• spi_replace_transfers(9)
• spi_split_transfers_maxsize(9)
• spi_split_transfers_maxwords(9)
• spi_set_cs_timing(9)
• spi_setup(9)
• spi_optimize_message(9)
• spi_unoptimize_message(9)
• devm_spi_optimize_message(9)
• spi_async(9)
• spi_sync(9)
• spi_sync_locked(9)
• spi_bus_lock(9)
• spi_bus_unlock(9)
• spi_write_then_read(9)

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and that's the whole page bestie, no crumbs left 💖 this one came from ./drivers/spi, it's part of the Kernel API Manual, and it's dated October 2026 ⭐ mwah, go unregister something responsibly 🧚