regmap_init_mdio(9)

💅 regmap_init_mdio(9) — the Kernel API Manual moment

okay so first things first, bestie: this page lives in the regmap_init_mdio(9) section of the Kernel API Manual, and it's literally just about setting up a register map. short page, big main character energy ✨

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🌸 NAME 🌸

regmap_init_mdio — Initialise register map. that's it, that's the whole vibe 🎀

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✨ SYNOPSIS ✨

regmap_init_mdio (mdio_dev , config );

like, you hand it a device and a config and it does the thing. periodt 💅

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🫶 ARGUMENTS 🫶

• mdio_dev — the Device that will be interacted with 🦋 (yes, this is the one getting the whole register-map glow-up)
• config — the Configuration for register map. it's giving "here's how you should behave" 📋

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👑 DESCRIPTION 👑

okay so here's the tea: the return value will be an ERR_PTR on error — so like, check it, don't just ignore it 😭 — or a valid pointer to a struct regmap. those are your two options, no in-between, no delulu.

ngl bestie, if you're getting an ERR_PTR back and trying to deref it anyway, that's not slay, that's a crash 💀

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🌈 SEE ALSO 🌈

the whole friend group, in order, no cap:

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_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_mmio(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)

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and that's the whole page, bestie — obsessed with how short it is fr fr 🧚

this little cutie is filed under ./include/linux, dated October 2026, and it's literally the regmap_init_mdio(9) of the Kernel API Manual. go forth and init your register maps, queen 👑💖