devm_therma...ice_register(9)

💅 devm_therma...ice_register(9) — Kernel API Manual, but make it make sense 💅

okay bestie, so we're in the kernel API manual today (yes, that one), and the star of the show is devm_thermal_fwnode_cooling_device_register ✨ she's got a long name, she's got main character energy, and she's literally here to register a thermal cooling device. no cap.

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✨ NAME ✨

devm_thermal_fwnode_cooling_device_register — register a thermal cooling device 🧊🔥

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🎀 SYNOPSIS 🎀

struct thermal_cooling_device *
devm_thermal_fwnode_cooling_device_register (struct device *dev , int
fwn_index , const char *type , void *devdata , const struct
thermal_cooling_device_ops *ops );

like, five arguments. she's high maintenance but she's worth it 🫶

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💖 ARGUMENTS 💖

• dev — a valid struct device pointer of a sensor device. valid, babes. valid. don't be out here passing garbage 🙈
• fwn_index — literally marked -- undescribed -- in the docs 💀 so yeah, that's all we know. iconic of her honestly.
• type — the thermal cooling device type.
• devdata — device private data. your stuff. your vibe. 🎀
• ops — standard thermal cooling devices callbacks.

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🌸 DESCRIPTION 🌸

so what does she actually do? this function will register a cooling device with a firmware node reference ✨ periodt.

this interface function adds a new thermal cooling device (fan/processor/...) to the /sys/class/thermal/ folder as cooling_device[0-*] 🌈 and then — the way that she does the absolute most — it tries to bind itself to all the thermal zone devices registered at the same time. multitasking queen 👑 lowkey obsessed.

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⭐ RETURN ⭐

she returns a pointer to the created struct thermal_cooling_device, or an ERR_PTR 😭

bestie listen to me: caller must check the return value with the IS_ERR*() helpers. this is not optional, this is not a drill, this is the whole vibe check 💀

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🦋 SEE ALSO 🦋

• Kernel file ./drivers/thermal/thermal_fw.c
• thermal_fwnode_cooling_device_register(9)

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and that's the page, bestie!! 🍓 dropped from ./drivers/thermal, dated October 2026, headed to you straight from the devm_therma...ice_register(9) era 💜 go forth and check your IS_ERR*() helpers, iykyk 🧚✨