regmap_init_mmio(9)

💅 regmap_init_mmio(9) — Kernel API Manual 🎀

okay so bestie, welcome to the Kernel API Manual, and today's main character is regmap_init_mmio — literally the glow-up ritual that turns your tiny baby register map into a fully functioning icon ✨

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🌸 NAME 🌸

regmap_init_mmio — Initialise register map

like, it's giving "wake up babe, new regmap just dropped" 💜

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🦋 SYNOPSIS 🦋

regmap_init_mmio (dev , regs , config );

no cap, that's the whole invocation. three lil arguments and you're off 🫶

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✨ ARGUMENTS ✨

• dev — the Device that will be interacted with. this is the whole entire point of the operation, she's the one actually being interacted with 💖
• regs — Pointer to memory-mapped IO region. yes. mmio. it's in the name, iykyk 🧚
• config — Configuration for register map. your settings, your vibes, your rules 👑

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🔥 DESCRIPTION 🔥

So here's the tea ☕ — the return value will be an ERR_PTR on error, or a valid pointer to a struct regmap if everything slayed. That's it. That's the deal. 💀

Also lowkey important: it implies 'fast_io'. Like, it just does that. periodt. ⭐

bestie please check your return value 🙈 — an ERR_PTR is literally the function telling you it did not eat. use your IS_ERR() checks, i'm begging 🥺

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👑 SEE ALSO 👑

okay this list is LONG and we're gonna get through all of it because every single one of these is iconic in her own right 🌈

Kernel file ./include/linux/regmap.h 💫

• struct reg_default(9)
• struct reg_sequence(9)
• regmap_read_poll_timeout(9)
• regmap_read_poll_timeout_atomic(9)
• regmap_field_read_poll_timeout(9)
• struct regmap_range(9)
• struct regmap_access_table(9)
• struct regmap_config(9)
• struct regmap_range_cfg(9)
• struct regmap_sdw_mbq_cfg(9)
• struct regmap_bus(9)
• regmap_init(9)
• regmap_init_i2c(9)
• regmap_init_mdio(9)
• regmap_init_sccb(9)
• regmap_init_slimbus(9)
• regmap_init_spi(9)
• regmap_init_spmi_base(9)
• regmap_init_spmi_ext(9)
• regmap_init_w1(9)
• regmap_init_mmio_clk(9)
• regmap_init_ac97(9)
• regmap_init_sdw(9)
• regmap_init_sdw_mbq(9)
• regmap_init_sdw_mbq_cfg(9)
• regmap_init_i3c(9)
• regmap_init_spi_avmm(9)
• regmap_init_fsi(9)
• devm_regmap_init(9)
• devm_regmap_init_i2c(9)
• devm_regmap_init_mdio(9)
• devm_regmap_init_sccb(9)
• devm_regmap_init_spi(9)
• devm_regmap_init_spmi_base(9)
• devm_regmap_init_spmi_ext(9)
• devm_regmap_init_w1(9)
• devm_regmap_init_mmio_clk(9)
• devm_regmap_init_mmio(9)
• devm_regmap_init_ac97(9)
• devm_regmap_init_sdw(9)
• devm_regmap_init_sdw_mbq(9)
• devm_regmap_init_sdw_mbq_cfg(9)
• devm_regmap_init_slimbus(9)
• devm_regmap_init_i3c(9)
• devm_regmap_init_spi_avmm(9)
• devm_regmap_init_fsi(9)
• struct reg_field(9)
• struct regmap_irq_type(9)
• struct regmap_irq(9)
• struct regmap_irq_chip(9)

not me listing all fifty-ish of these 😭 but like, they're all family, we don't leave anyone out 💅

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<div align="center">🌸 🦋 🎀 🦋 🌸</div>

k bye bestie, this page lives in ./include/linux and the version/date stamp on it is October 2026 — so mark your calendar, the regmap init is eternal ⭐👑💜