ata_down_xfermask_limit(9)

💅 ata_down_xfermask_limit(9) — Kernel API Manual, section 9

okay bestie, welcome to the group chat 💖 this is a page from the Kernel API Manual, section 9, and it's all about nudging a device's transfer masks downward. no cap.

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✨ NAME ✨

ata_down_xfermask_limit — adjust dev xfer masks downward 🦋

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🌸 SYNOPSIS 🌸

int ata_down_xfermask_limit (struct ata_device *dev , unsigned int sel );

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🎀 ARGUMENTS 🎀

• dev — the device whose xfer masks you're adjusting, bestie 💅
• sel — the ATA_DNXFER_* selector, pick your vibe

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👑 DESCRIPTION 👑

So here's the tea: this function adjusts the xfer masks of dev downward. That's the whole assignment. 🫶

okay but listen — this function does not apply the change. it just sets the limit. 😭 you literally have to invoke ata_set_mode afterwards to actually apply it. don't skip that step, i'm begging.

LOCKING: inherited from caller. not us, not our problem, it's yours 💀

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⭐ RETURN ⭐

• 0 on success, slay 🎉
• negative errno on failure, tragic 🙈

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🌈 SEE ALSO 🌈

Kernel file ./drivers/ata/libata-core.c — plus literally the entire extended universe of ATA functions, iykyk. here's the full rundown, no skips 🧚:

• ata_link_next(9)
• ata_dev_next(9)
• ata_dev_phys_link(9)
• ata_force_cbl(9)
• ata_force_pflags(9)
• ata_force_link_limits(9)
• ata_force_xfermask(9)
• ata_force_quirks(9)
• atapi_cmd_type(9)
• ata_set_rwcmd_protocol(9)
• ata_tf_read_block(9)
• ata_build_rw_tf(9)
• ata_pack_xfermask(9)
• ata_unpack_xfermask(9)
• ata_xfer_mask2mode(9)
• ata_xfer_mode2mask(9)
• ata_xfer_mode2shift(9)
• ata_mode_string(9)
• ata_dev_classify(9)
• ata_id_string(9)
• ata_id_c_string(9)
• ata_read_native_max_address(9)
• ata_set_max_sectors(9)
• ata_hpa_resize(9)
• ata_dump_id(9)
• ata_id_xfermask(9)
• ata_exec_internal(9)
• ata_pio_need_iordy(9)
• ata_pio_mask_no_iordy(9)
• ata_do_dev_read_id(9)
• ata_dev_read_id(9)
• ata_dev_power_set_standby(9)
• ata_dev_power_set_active(9)
• ata_read_log_page(9)
• ata_dev_configure(9)
• ata_cable_40wire(9)
• ata_cable_80wire(9)
• ata_cable_unknown(9)
• ata_cable_ignore(9)
• ata_cable_sata(9)
• sata_print_link_status(9)
• ata_dev_pair(9)
• ata_timing_cycle2mode(9)
• ata_set_mode(9)
• ata_wait_ready(9)
• ata_wait_after_reset(9)
• ata_std_prereset(9)
• ata_std_postreset(9)
• ata_dev_same_device(9)
• ata_dev_reread_id(9)
• ata_dev_revalidate(9)
• ata_is_40wire(9)
• cable_is_40wire(9)
• ata_dev_xfermask(9)
• ata_dev_set_xfermode(9)
• ata_dev_set_feature(9)
• ata_dev_init_params(9)
• atapi_check_dma(9)
• ata_std_qc_defer(9)
• ata_sg_init(9)
• ata_sg_clean(9)
• ata_sg_setup(9)
• swap_buf_le16(9)
• ata_qc_free(9)
• ata_qc_complete(9)
• ata_qc_get_active(9)
• ata_qc_issue(9)
• ata_phys_link_online(9)
• ata_phys_link_offline(9)
• ata_link_online(9)
• ata_link_offline(9)
• ata_host_suspend(9)
• ata_host_resume(9)
• ata_dev_init(9)
• ata_link_init(9)
• sata_link_init_spd(9)
• ata_port_alloc(9)
• ata_host_alloc(9)
• ata_host_alloc_pinfo(9)
• ata_finalize_port_ops(9)
• ata_host_start(9)
• ata_host_init(9)
• ata_host_register(9)
• ata_host_activate(9)
• ata_dev_free_resources(9)
• ata_port_detach(9)
• ata_host_detach(9)
• ata_pci_remove_one(9)
• ata_platform_remove_one(9)
• ata_msleep(9)
• ata_wait_register(9)

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okay that's the whole page, you ate that 🍓 mwah 💜

sign-off time: this lil masterpiece lives in the source tree at ./drivers/ata, dated October 2026, shipped under the Kernel API Manual banner as ata_down_xfermask_limit(9) — iconic, no notes ✨👑