STRUCT SBTSI_DATA(9)

✨ struct sbtsi_data(9) ✨

okay so bestie, picture this: it's struct sbtsi_data(9) from the Kernel API Manual, and it's literally the driver's private little diary for an AMD SB-TSI device 💖 this whole page is just us going through every single field in that struct, no skips, no cap 🫶

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🌸 NAME 🌸

struct sbtsi_data — driver private data for an AMD SB-TSI device

like, it's the driver's personal stash of state. main character energy fr 💅

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✨ SYNOPSIS ✨

struct sbtsi_data {
    union {
      struct i2c_client *client;
      struct i3c_device *i3cdev;
    };
    struct miscdevice sbtsi_misc_dev;
    struct mutex lock;
    struct kref kref;
    u8 dev_addr;
    bool ext_range_mode;
    bool read_order;
    bool is_i3c;
    bool detached;
 };

copy it exactly like that, don't be out here editing structs, that's not the vibe 🙈

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🎀 Members 🎀

• {unnamed_union} — anonymous 👑 it's the unnamed one, she has no name, she simply exists.
• client — the underlying I2C client ngl, this is who we're actually talking to.
• i3cdev — the underlying I3C device (when using I3C bus) — so like, the I3C-era version of the above 🦋
• sbtsi_misc_dev — miscdevice exposing ioctl interface at /dev/sbtsi-<addr> — yup, that's a real path, that's where the ioctl interface lives, slay ✨
• lock — mutex protecting concurrent access to the device — literally the bouncer at the club, keeps everybody from crashing into each other 😭
• kref — reference count; keeps sbtsi_data alive while misc fds are open — she stays alive until the last fd leaves the group chat 💀
• dev_addr — I2C/I3C device address, used as the auxiliary device instance id and name the misc device node — so it's doing double duty and honestly? iconic 🌟
• ext_range_mode — sensor uses extended temperature range 🔥 (no, that's not a metaphor, that's the actual flag)
• read_order — if set, decimal part must be read before integer part ⚠️ okay so this one matters, order is not a suggestion, decimal FIRST, then integer, don't get cute with it
• is_i3c — true when the device is accessed over I3C ✅
• detached — set on driver unbind; open/ioctl return -ENODEV afterward — so once she's detached, open/ioctl are gonna hit you with -ENODEV, periodt 💅

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🔥 SEE ALSO 🔥

• Kernel file ./include/linux/misc/tsi.h
• sbtsi_xfer(9)

go read those too, iykyk 🧚

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and that's the whole page bestie, no crumbs left 🍓 this little gem came from the kernel file path ./include/linux/misc and it's dated October 2026 — so yeah, mark your calendar, she's from the future 💜 bye babes, go read your structs 💖