STRUCT IRQ_DOMAIN_INFO(9)

🌸 NAME 🌸

okay so bestie, welcome to the struct irq_domain_info(9) page in the Kernel API Manual — and it's literally the blueprint for spinning up an interrupt domain 💖

struct irq_domain_info — Domain information structure. that's the whole assignment. this struct is where you tell the kernel everything it needs to know about the irq domain you're about to create 🎀

✨ SYNOPSIS ✨

here's the whole thing verbatim, no cap — every field, every type, every #ifdef, exactly as written:

struct irq_domain_info {
    struct fwnode_handle                    *fwnode;
    unsigned int                            domain_flags;
    unsigned int                            size;
    irq_hw_number_t hwirq_max;
    int direct_max;
    unsigned int                            hwirq_base;
    unsigned int                            virq_base;
    enum irq_domain_bus_token               bus_token;
    const char                              *name_suffix;
    const struct irq_domain_ops             *ops;
    void *host_data;
    struct device                           *dev;
  #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY;
    struct irq_domain                       *parent;
  #endif;
    struct irq_domain_chip_generic_info     *dgc_info;
    int (*init)(struct irq_domain *d);
    void (*exit)(struct irq_domain *d);
 };

not the #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY; gate on parent bestie — that field only exists when hierarchy support is compiled in 🙈 the rest are always there.

🦋 Members 🦋

time for the vibe check on every single field 💅

• fwnode — the firmware node for the interrupt controller. this is where the domain learns who it belongs to 🧚
• domain_flags — extra flags you want to add on top of the domain flags. sprinkle responsibly ✨
• size — size of the linear map; 0 means radix mapping only, nothing linear about it 💀
• hwirq_max — the maximum number of interrupts the controller supports. the ceiling, the limit, the moment 🫶
• direct_max — the maximum value of direct maps. use ~0 for no limit, and 0 for no direct mapping at all. choose your fighter 👑
• hwirq_base — the first hardware interrupt number — legacy domains only, so if you're not doing legacy this isn't your moment 🌈
• virq_base — the first Linux interrupt number, for legacy domains that want to immediately associate the interrupts right after domain creation. instant association, iconic behavior ⭐
• bus_token — the domain bus token 🔥
• name_suffix — optional name suffix, and lowkey it's there to avoid collisions when multiple domains get added using the same fwnode. two domains, one fwnode, chaos averted 💖
• ops — the domain operation callbacks. the actual behavior lives here 🎀
• host_data — controller private data pointer. your own little pocket of stuff 🍓
• dev — the device which creates the domain 🦋
• parent — pointer to the parent irq domain, used in a hierarchy domain. only around when CONFIG_IRQ_DOMAIN_HIERARCHY is set, per the synopsis above 💜
• dgc_info — Geneneric chip information structure pointer, used to create generic chips for the domain if not NULL 🧚
• init — function called when the domain is created. lets you do some additional domain initialisation, a little pre-game ritual ✨
• exit — function called when the domain is destroyed. lets you do some additional cleanup operation — the goodbye routine, the tidy-up, the "leaving the group chat" 🌸

🔍 SEE ALSO 🔍

go read these next, bestie, they're all in the Kernel file ./include/linux/irqdomain.h:

• struct irq_fwspec(9)
• struct irq_fwspec_info(9)
• struct irq_domain_ops(9)
• struct irq_domain(9)
• irq_domain_create_linear(9)
• irq_create_mapping(9)
• irq_resolve_mapping(9)
• irq_find_mapping(9)
• irq_domain_create_hierarchy(9)
• irq_domain_alloc_irqs(9)

and that's the whole page, periodt 💅 this one came out of ./include/linux, dated October 2026 — so if you're ever wondering where it lives, that's the spot, mwah 🫶💖