cdx_mcdi_msi_enable(9)

💅 cdx_mcdi_msi_enable(9) — the kernel API manual, but make it make sense

okay so bestie, welcome to cdx_mcdi_msi_enable — it's a kernel API manual page and honestly it's giving "small function, big responsibilities" ✨ this one lets you turn MSIs on or off for a cdx device, and that device is identified by bus_num:dev_num 🎀

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🌸 NAME 🌸

cdx_mcdi_msi_enable — Enable/Disable MSIs for cdx device represented by bus_num:dev_num 💖

✨ SYNOPSIS ✨

int cdx_mcdi_msi_enable (struct cdx_mcdi *cdx , u8 bus_num , u8 dev_num
, bool enable );

that's the whole vibe, no cap 🫶

🦋 ARGUMENTS 🦋

• cdx — pointer to MCDI interface. literally the main character of this call 🔥
• bus_num — Bus number. yes bestie, the bus 🙈
• dev_num — Device number. and the device on it 💫
• enable — Enable msi's if set, disable otherwise. so like, true = slay, false = not slay 💅

🌈 RETURN 🌈

• 0 on success 🎉
• <0 on failure 😭 (a negative number, iykyk — it did not eat)

👑 SEE ALSO 👑

Kernel file ./drivers/cdx/controller/mcdi_functions.h — go read it, it's iconic ⭐

and the whole friend group of related calls:

• cdx_mcdi_get_num_buses(9)
• cdx_mcdi_get_num_devs(9)
• cdx_mcdi_get_dev_config(9)
• cdx_mcdi_bus_enable(9)
• cdx_mcdi_bus_disable(9)
• cdx_mcdi_write_msi(9)
• cdx_mcdi_reset_device(9)
• cdx_mcdi_bus_master_enable(9)

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bestie note: the arguments section says "Enable msi's if set, disable otherwise" — that's the original's wording, so that's exactly what we're keeping. no inventing behaviour over here, fr fr 🌸

okay and that's the page!! 💜 this one lives in ./drivers/cdx/controller, dated October 2026, and it goes by cdx_mcdi_msi_enable(9) — periodt, go enable some MSIs responsibly 🧚‍♀️🍓