mmc_regulator_set_vqmmc(9)

📦 version 7.3.1, in nixpkgs unstable

💅 mmc_regulator_set_vqmmc(9) 💅

okay bestie, welcome to the Kernel API Manual ✨ this is the page for mmc_regulator_set_vqmmc(9) and we're gonna get you so comfy with it, no cap 🫶

🌸 NAME 🌸

mmc_regulator_set_vqmmc — set VQMMC as per the ios 👑 literally what it says on the tin

⭐ SYNOPSIS ⭐

int mmc_regulator_set_vqmmc (struct mmc_host *mmc , struct mmc_ios *ios
);

it's giving "two pointers in, one int out" 💖

🎀 ARGUMENTS 🎀

  • mmc — the host to regulate 💅 this is the card host we're out here voltage-matching for
  • ios — io bus settings 🦋 the settings we're reading the vibe (and the volts) from

🔥 DESCRIPTION 🔥

okay so for 3.3V signaling, we try to match VQMMC to VMMC as closely as possible. that's on purpose — it matches the behavior of old boards where VQMMC and VMMC were supplied by the same supply 🫶 and the Bus Operating conditions for 3.3V signaling in the SD card spec also define VQMMC in terms of VMMC, so like… we're just following the lore 📜 if this is not possible we'll try the full 2.7-3.6V of the spec. slay 💅

for 1.2V and 1.8V signaling we'll try to get as close as possible to the requested voltage 🎯 this is definitely a good idea for UHS, where there's a separate regulator on the card that's trying to make 1.8V and it's best if we match. like, bestie, matching is the move. periodt ✨

this function is expected to be used by a controller's start_signal_voltage_switch function 👑 main character energy fr fr

🦋 SEE ALSO 🦋

Kernel file ./drivers/mmc/core/regulator.c and its whole friend group 💜:

ngl that's the whole page, go forth and regulate 💀🧚

and that's a wrap, bestie 🌈 this lil drop came from ./drivers/mmc/core, dated October 2026 — mwah, love u, bye 💖🎀🌸

📦 where this page comes from