device_online(9)

🎀 device_online(9) 🎀

okay bestie come closer — this is a page from the Kernel API Manual, and it's device_online(9), which is genuinely the "you can come back in, the party's still going" function of the device world. no cap. 💅

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✨ NAME ✨

device_online — puts the device back online after device_offline() actually succeeded. that's it. that's the whole vibe. 🫶

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🌸 SYNOPSIS 🌸

int device_online (struct device *dev );

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🦋 ARGUMENTS 🦋

• dev — the device you're putting back online. literally her. the main character of this call. 👑

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💖 DESCRIPTION 💖

okay so picture this: device_offline has already been successfully executed for dev, and the device has not been removed since then. if that's the sitch, then device_online runs its bus type's .online callback, which is basically the kernel's way of announcing "yeah she's usable again, we're so back." ✨

🚨 and bestie, listen — call it under device_hotplug_lock. that's not a suggestion, that's the assignment. lock first, then vibe. 🔐

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🌈 SEE ALSO 🌈

this list is iconic and also lowkey a whole crowd, so buckle up. the kernel file ./drivers/base/core.c plus everyone in the group chat:

the fwnode link girlies 🧚

• __fwnode_link_add(9)
• __fwnode_link_del(9)
• __fwnode_link_cycle(9)
• fwnode_links_purge_suppliers(9)
• fwnode_links_purge_consumers(9)
• fwnode_links_purge(9)
• __fwnode_links_move_consumers(9)
• __fw_devlink_pickup_dangling_consumers(9)
• fw_devlink_refresh_fwnode(9)
• fwnode_is_ancestor_of(9)
• fwnode_get_next_parent_dev(9)
• __fw_devlink_relax_cycles(9)
• fw_devlink_create_devlink(9)
• __fw_devlink_link_to_consumers(9)
• __fw_devlink_link_to_suppliers(9)
• get_dev_from_fwnode(9)

the device link crew 🔗

• device_is_dependent(9)
• device_pm_move_to_tail(9)
• device_link_wait_removal(9)
• device_link_add(9)
• device_link_del(9)
• device_link_remove(9)
• device_links_check_suppliers(9)
• __device_links_queue_sync_state(9)
• device_links_flush_sync_list(9)
• device_links_force_bind(9)
• device_links_driver_bound(9)
• __device_links_no_driver(9)
• device_links_no_driver(9)
• device_links_driver_cleanup(9)
• device_links_busy(9)
• device_links_unbind_consumers(9)
• device_links_purge(9)
• wait_for_init_devices_probe(9)

the device lifecycle squad 🐛

• dev_driver_string(9)
• device_release(9)
• devm_device_add_group(9)
• devices_kset_move_before(9)
• devices_kset_move_after(9)
• devices_kset_move_last(9)
• device_create_file(9)
• device_remove_file(9)
• device_remove_file_self(9)
• device_create_bin_file(9)
• device_remove_bin_file(9)
• device_initialize(9)
• kobject_has_children(9)
• dev_set_name(9)
• device_add(9)
• device_register(9)
• get_device(9)
• put_device(9)
• device_del(9)
• device_unregister(9)
• device_get_devnode(9)

the "walk the children" gang 🚶‍♀️

• device_for_each_child(9)
• device_for_each_child_reverse(9)
• device_for_each_child_reverse_from(9)
• device_find_child(9)

the sibling page (her other half) 💫

• device_offline(9)

the root device crew 🌱

• __root_device_register(9)
• root_device_unregister(9)

the create / destroy / rename committee 🎀

• device_create(9)
• device_create_with_groups(9)
• device_destroy(9)
• device_rename(9)
• device_move(9)
• device_change_owner(9)
• device_shutdown(9)
• dev_err_probe(9)
• dev_warn_probe(9)

the of_node & fwnode setters 🍓

• set_primary_fwnode(9)
• set_secondary_fwnode(9)
• device_remove_of_node(9)
• device_add_of_node(9)
• device_set_of_node_from_dev(9)

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okay that's the whole page, you ate that ngl 💅 go forth and bring your devices back online responsibly. and remember: this gem is filed under ./drivers/base, dated October 2026 — screenshot it, cite it, slay. 🌈⭐👑