STRUCT UIO_INFO(9)

🦋 struct uio_info(9) — like, the whole vibe of a UIO device, bestie 🦋

okay so this is from the Kernel API Manual, and it's literally the cheat sheet for struct uio_info — the thing that tells the kernel everything your UIO device can do ✨ no cap, this is the main character struct.

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💖 NAME 💖

struct uio_info — UIO device capabilities 🫶

like… it's the capabilities list. for a UIO device. that's the whole assignment 💅

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🌸 SYNOPSIS 🌸

here's the struct in all its glory, typed out exactly, don't @ me:

struct uio_info {
    struct uio_device       *uio_dev;
    const char              *name;
    const char              *version;
    struct uio_mem          mem[MAX_UIO_MAPS];
    struct uio_port         port[MAX_UIO_PORT_REGIONS];
    long irq;
    unsigned long           irq_flags;
    void *priv;
    irqreturn_t (*handler)(int irq, struct uio_info *dev_info);
    int (*mmap_prepare)(struct uio_info *info, struct vm_area_desc *desc);
    int (*open)(struct uio_info *info, struct inode *inode);
    int (*release)(struct uio_info *info, struct inode *inode);
    int (*irqcontrol)(struct uio_info *info, s32 irq_on);
 };

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🎀 Members 🎀

bestie, let's go field by field, one by one, no skipping (I would never) 💜

• uio_dev — the UIO device this info belongs to 👑 like, whose info even is this
• name — device name ✨ give it a cute one
• version — device driver version 🔥
• mem — list of mappable memory regions, and size==0 means end of list 🧚 (the list just… stops, iconic)
• port — list of port regions, size==0 for end of list 🙈 same deal
• irq — interrupt number, or UIO_IRQ_CUSTOM ⭐
• irq_flags — flags for request_irq 💫
• priv — optional private data 🍓 optional!! it's giving low-maintenance
• handler — the device's irq handler 💀 the one actually doing the work
• mmap_prepare — mmap_prepare operation for this uio device 🌈
• open — open operation for this uio device 💖
• release — release operation for this uio device 🦋
• irqcontrol — disable/enable irqs when 0/1 is written to /dev/uioX 🎯 (yes, that's the whole trigger, 0 or 1, periodt)

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🌟 SEE ALSO 🌟

go read these next, iykyk 📚

Kernel file ./include/linux/uio_driver.h, plus struct uio_mem(9), struct uio_port(9), uio_register_device(9), devm_uio_register_device(9) 💅

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okay that's the whole page, bestie 💖 huge slay. this one lives in ./include/linux, stamped October 2026, and it goes by struct uio_info(9) — go forth and register your devices 🫶✨🎀