STRUCT RSMU_DDATA(9)

💜 struct rsmu_ddata(9) — the kernel API manual, but make it make sense

okay so bestie, welcome to struct rsmu_ddata(9) 🦋 — yes that's the actual man page name, it lives in the Kernel API Manual section 9, and it's literally the device data structure for sub devices. that's the whole NAME. short, sweet, iconic. periodt 💅

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✨ NAME ✨

struct rsmu_ddata — device data structure for sub devices. that's it, that's the vibe 🎀

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🌸 SYNOPSIS 🌸

here's the whole struct, copied exactly, don't touch a single character bestie:

struct rsmu_ddata {
    struct device *dev;
    struct regmap *regmap;
    struct mutex lock;
    enum rsmu_type type;
    u32 page;
 };

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👑 Members 👑

• dev — the i2c/spi device. like, the actual hardware friend we're talking to 🫶
• regmap — the i2c/spi bus access. this is the little doorway the kernel uses to poke the registers 💫
• lock — a mutex that sub devices grab so that a whole series of bus access requests doesn't get interrupted mid-way. no cutting in line, no cap 😤🔒
• type — the RSMU device type. the enum rsmu_type situation, iykyk ✨
• page — i2c/spi bus driver internal use only. bestie this one is not for you, hands off 🙈 (genuinely, it's internal use only, don't go poking it)

ngl that lock field is doing a lot of heavy lifting — it's the difference between a clean burst of bus accesses and absolute chaos 💀

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🦋 SEE ALSO 🦋

• Kernel file ./include/linux/mfd/rsmu.h — go read it, it's right there 👀

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and that's the whole page, bestie, you ate that 🍓

sign-off time: this lil masterpiece comes from ./include/linux/mfd, dated October 2026, and it's filed under struct rsmu_ddata(9). slay 💖✨