STRUCT HDAC_EXT2_LINK(9)

💖 struct hdac_ext2_link(9) 💖

okay so bestie, welcome to the struct hdac_ext2_link(9) page — this is straight out of the Kernel API Manual and it's literally the HDAudio extended+alternate link. yes that's a lot of adjectives. it ate. let's get into it 🫶

✨ NAME ✨

struct hdac_ext2_link — HDAudio extended+alternate link. that's it, that's the whole name, and it's iconic 💅

🌸 SYNOPSIS 🌸

here's the whole struct, typed out exactly, no cap:

struct hdac_ext2_link {
    struct hdac_ext_link hext_link;
    bool alt;
    bool intc;
    bool ofls;
    bool lss;
    int slcount;
    int elid;
    int elver;
    u32 leptr;
    struct mutex eml_lock;
    int sublink_ref_count[HDAML_MAX_SUBLINKS];
    void __iomem *base_ptr;
    u32 instance_offset;
    u32 shim_offset;
    u32 ip_offset;
    u32 shim_vs_offset;
    unsigned long mic_privacy_mask;
};

🎀 Members 🎀

okay now the member-by-member vibe check, one by one, nobody gets left out:

• hext_link — a struct hdac_ext_link. it's the ext link inside the ext2 link, like a little link inception moment 🌀
• alt — flag set for alternate extended links. alternate as in✨different era✨
• intc — boolean for interrupt capable. it can get interrupted, and honestly same 😭
• ofls — boolean for offload support. it's giving delegation 👑
• lss — boolean for link synchronization capabilities. keeping everybody in sync, main character energy fr fr
• slcount — sublink count. how many sublinks we're dealing with here 🔢
• elid — extended link ID (the AZX_REG_ML_LEPTR_ID_ defines). it's the ID bestie, it has one 🪪
• elver — extended link version. which version? this one. no cap 💫
• leptr — extended link pointer. it points at stuff. that's the job 🫡
• eml_lock — mutual exclusion to access shared registers, e.g. the CPA/SPA bits in the LCTL register. do NOT touch the shared registers without holding this, that's the whole point 💀
• sublink_ref_count — array of refcounts, required to power-manage sublinks independently. HDAML_MAX_SUBLINKS of them, one per sublink, so each one can be power-managed on its own little journey 🌈
• base_ptr — pointer to shim/ip/shim_vs space. a void __iomem *, very mysterious, very "don't ask" 🙈
• instance_offset — offset between each of the slcount instances managed by link. the spacing between the instances, literally 📏
• shim_offset — offset to the SHIM register base. shim base located ✅
• ip_offset — offset to the IP register base. ip base located ✅
• shim_vs_offset — offset to the vendor-specific (VS) SHIM base. the VS shim, very exclusive 💅
• mic_privacy_mask — bitmask of sublinks where mic privacy is applied. an unsigned long, and yes it's protecting your mic, say thank you 🎤

🦋 SEE ALSO 🦋

• Kernel file ./sound/soc/sof/intel/hda-mlink.c — go read the source, iykyk 📖

and that's the page!! signing off from ./sound/soc/sof/intel, dated October 2026, struct hdac_ext2_link(9) — mwah, slay, go power-manage those sublinks independently 💖✨🎀