usb_cache_string(9)

💖 usb_cache_string(9) 💖

okay so bestie, welcome to the Kernel API Manual — yes we're literally in the kernel today, it's giving main character energy and you're gonna slay this 🫶

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✨ NAME ✨

usb_cache_string — reads a string descriptor and caches it so you can use it later, no cap 💅

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🌸 SYNOPSIS 🌸

char * usb_cache_string (struct usb_device *udev , int index );

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🎀 ARGUMENTS 🎀

• udev — the device whose string descriptor is being read, like that's the whole vibe of this argument 💖
• index — the descriptor index. which one you want, bestie ✨

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🦋 RETURN 🦋

A pointer to a kmalloc'ed buffer that's holding the descriptor string — so yes, it's kmalloc'ed, keep that in mind 👑

Or NULL if the index is 0, or if the string could not be read. Lowkey the saddest outcome but it happens 😭

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⭐ SEE ALSO ⭐

Kernel file ./drivers/usb/core/message.c, plus the whole friend group:

• usb_control_msg(9)
• usb_control_msg_send(9)
• usb_control_msg_recv(9)
• usb_interrupt_msg(9)
• usb_bulk_msg(9)
• usb_bulk_msg_killable(9)
• usb_sg_init(9)
• usb_sg_wait(9)
• usb_sg_cancel(9)
• usb_get_descriptor(9)
• usb_get_string(9)
• usb_string(9)
• usb_get_status(9)
• usb_clear_halt(9)
• usb_disable_endpoint(9)
• usb_reset_endpoint(9)
• usb_disable_interface(9)
• usb_disable_device(9)
• usb_enable_endpoint(9)
• usb_enable_interface(9)
• usb_set_interface(9)
• usb_reset_configuration(9)
• usb_set_wireless_status(9)
• usb_driver_set_configuration(9)
• cdc_parse_cdc_header(9)

like okay that's the entire contact list, go say hi 🧚💜

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fr fr read the string, cache the string, return the pointer. that's the whole plot 🙈

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signed, sealed, delivered with love from ./drivers/usb/core 🌈 — October 2026, this page's version era, date and all, mwah 🍓💜