isst_if_cdev_register(9)

💅 isst_if_cdev_register — Kernel API Manual

okay so bestie, welcome to the isst_if_cdev_register(9) page ✨ this is a Kernel API Manual entry, and it's lowkey about registering a callback for IOCTL. let's get into it 🫶

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✨ NAME ✨

isst_if_cdev_register — Register callback for IOCTL 🎀

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🌸 SYNOPSIS 🌸

int isst_if_cdev_register (int device_type , struct isst_if_cmd_cb *cb );

like, that's the whole signature, no cap 💅

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🦋 ARGUMENTS 🦋

• device_type — the device type this callback handling. that's the one it's for, periodt.
• cb — Callback structure. the vibes container, basically.

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👑 DESCRIPTION 👑

okay so here's the tea ☕ this function registers a callback to device_type. main character behavior incoming:

• On the very first call it will register a misc device, which is used for user kernel interface. iconic ✨
• Other calls simply increment ref count. no drama, just counting 🔥
• Registry will fail if the user already opened the misc device for operation. like, read the room 😭
• Also if the misc device creation failed, then it will not try again and all callers will get failure code. ngl that's a permanent vibe check fail 💀

bestie pls note: that last bit is fr fr — no retry, no second chances, everybody gets the failure code. 🙈

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💖 RETURN 💖

Return the return value from the misc creation device or -EINVAL for unsupported device type. slay, simple 🎀

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/platform/x86/intel/speed_select_if/isst_if_common.c 🦋
• isst_store_cmd(9)
• isst_resume_common(9)
• isst_if_mbox_cmd_invalid(9)
• isst_if_mbox_cmd_set_req(9)
• isst_if_get_pci_dev(9)
• isst_if_cdev_unregister(9)

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and that's the page, bestie!! 🫶 this little number lives at ./drivers/platform/x86/intel/s... and it's dated October 2026 — yes, from the future, we love that for us ⭐ go read the source, ily, bye 💜