STRUCT I3C_CCC_MRL(9)

💖 struct i3c_ccc_mrl(9) — the Kernel API Manual, but make it cute 💖

okay so bestie, you're in the Kernel API Manual and we're about to talk about struct i3c_ccc_mrl — the payload that gets passed to SETMRL/GETMRL CCC. lowkey iconic, ngl. ✨

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✨ NAME ✨

struct i3c_ccc_mrl — the payload passed to SETMRL/GETMRL CCC. 🎀

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🌸 SYNOPSIS 🌸

struct i3c_ccc_mrl {
    __be16 read_len;
    u8 ibi_len;
};

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🦋 Members 🦋

• ibi_len — the maximum IBI payload length. that's the vibe check for how big your IBI can be, fr fr 💅

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🧚 Description 🧚

okay so listen up: the maximum read length is only applicable to SDR private messages or extended Read CCCs (like GETXTIME, iykyk). and the IBI length? that one's only valid if the I3C slave is IBI capable — meaning I3C_BCR_IBI_REQ_CAP is set. no cap, that's the whole rule. 💀

bestie pls don't forget: if I3C_BCR_IBI_REQ_CAP isn't set, the IBI length is giving nothing. it's not valid. periodt. 🙈

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👑 SEE ALSO 👑

• Kernel file ./include/linux/i3c/ccc.h 🍓
• struct i3c_ccc_events(9)
• struct i3c_ccc_mwl(9)
• struct i3c_ccc_dev_desc(9)
• struct i3c_ccc_defslvs(9)
• enum i3c_ccc_test_mode(9)
• struct i3c_ccc_enttm(9)
• struct i3c_ccc_setda(9)
• struct i3c_ccc_getpid(9)
• struct i3c_ccc_getbcr(9)
• struct i3c_ccc_getdcr(9)
• struct i3c_ccc_getstatus(9)
• struct i3c_ccc_getaccmst(9)
• struct i3c_ccc_bridged_slave_desc(9)
• struct i3c_ccc_setbrgtgt(9)
• enum i3c_sdr_max_data_rate(9)
• enum i3c_tsco(9)
• struct i3c_ccc_getmxds(9)
• struct i3c_ccc_gethdrcap(9)
• enum i3c_ccc_setxtime_subcmd(9)
• struct i3c_ccc_setxtime(9)
• struct i3c_ccc_getxtime(9)
• struct i3c_ccc_cmd_payload(9)
• struct i3c_ccc_cmd_dest(9)
• struct i3c_ccc_cmd(9)

like that's a whole friend group of structs and enums, and they're all invited to the function call party. 💜

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and that's the whole page bestie, you ate that. 🫶 this cutie lives at ./include/linux/i3c and the version is October 2026, under the very official title struct i3c_ccc_mrl(9). slay, go read some kernel headers, mwah 💋🌈