STRUCT OMAP_HWMOD_CLASS(9)

💖 struct omap_hwmod_class(9) 💖

Okay so this is from the Kernel API Manual, bestie — and it’s literally the blueprint for the type of an IP block. Let’s get into it 🫶✨

🎀 NAME 🎀

struct omap_hwmod_class — the type of an IP block 💅

✨ SYNOPSIS ✨

struct omap_hwmod_class {
    const char                              *name;
    struct omap_hwmod_class_sysconfig       *sysc;
    int (*pre_shutdown)(struct omap_hwmod *oh);
    int (*reset)(struct omap_hwmod *oh);
    void (*lock)(struct omap_hwmod *oh);
    void (*unlock)(struct omap_hwmod *oh);
};

💅 Members 💅

Here’s the cast of this struct, no cap 🎀

• name — name of the hwmod_class ✨
• sysc — device SYSCONFIG/SYSSTATUS register data 🎀
• pre_shutdown — ptr to fn to be executed immediately prior to device shutdown 🫶
• reset — ptr to fn to be executed in place of the standard hwmod reset fn 🔁
• lock — ptr to fn to be executed to lock IP registers 🔒
• unlock — ptr to fn to be executed to unlock IP registers 🔓

🌈 Description 🌈

This represents the class of an OMAP hardware “modules” situation — think timer, smartreflex, gpio, uart... 👑 It’s giving “blueprint for a whole category of hardware blocks,” periodt.

pre_shutdown is a function that will be run immediately before hwmod clocks are disabled, etc. It’s intended for use for hwmods like the MPU watchdog, which cannot be disabled with the standard omap_hwmod_shutdown. The function should return 0 upon success, or some negative error upon failure. Returning an error will cause omap_hwmod_shutdown to abort the device shutdown and return an error 💀

If reset is defined, then the function it points to will be executed in place of the standard hwmod _reset code in mach-omap2/omap_hwmod.c. This is needed for IP blocks which have unusual reset sequences — usually processor IP blocks like the IVA. So yeah, custom reset main character energy 🔁✨

👀 SEE ALSO 👀

• Kernel file ./arch/arm/mach-omap2/omap_hwmod.h
• struct omap_hwmod_rst_info(9)
• struct omap_hwmod_opt_clk(9)
• struct omap_hwmod_omap2_firewall(9)
• struct omap_hwmod_ocp_if(9)
• struct omap_hwmod_class_sysconfig(9)
• struct omap_hwmod_omap2_prcm(9)
• struct omap_hwmod_omap4_prcm(9)
• struct omap_hwmod(9)

Source check, bestie: ./arch/arm/mach-omap2 — date: October 2026 — manual page: struct omap_hwmod_class(9). That’s the whole thing, mwah 💋💖