regmap_write(9)

💅 regmap_write(9) — from the Kernel API Manual, bestie 🎀

okay so this is the page for regmap_write(9). yes the title and the manual name are the same thing, we love a self-titled icon 👑 — it's a section 9 (kernel API) page, and it's about writing exactly one value to exactly one register. tiny scope, huge slay ✨

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🌸 NAME 🌸

regmap_write — write a value to a single register 💖

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✨ SYNOPSIS ✨

int regmap_write (struct regmap *map , unsigned int reg , unsigned int
       val );

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🫶 ARGUMENTS 🫶

• map — the register map you're writing into. this is the whole vibe, it's the thing that knows where all the registers live 🗺️
• reg — the one specific register you're writing to. just the one. single-target energy 💅
• val — the value that's going in there. that's it, that's the payload 🎁

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💜 DESCRIPTION 💜

so here's the whole deal: you call this, and on success you get a value of zero back 🎉 zero is the good number, zero means we ate and left no crumbs.

if something goes wrong, you get a negative errno back 😭 so like, negative = not good, check it, handle it, don't just ignore it bestie fr fr.

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🦋 SEE ALSO 🦋

the kernel file lives at ./drivers/base/regmap/regmap.c, and here's the whole friend group, in the order the page gives them 👯‍♀️

• devm_regmap_field_alloc(9), regmap_field_bulk_alloc(9), devm_regmap_field_bulk_alloc(9), regmap_field_bulk_free(9), devm_regmap_field_bulk_free(9), devm_regmap_field_free(9)
• regmap_field_alloc(9), regmap_field_free(9), regmap_reinit_cache(9), regmap_exit(9), dev_get_regmap(9), regmap_get_device(9)
• regmap_can_raw_write(9), regmap_get_raw_read_max(9), regmap_get_raw_write_max(9), regmap_write_async(9), regmap_raw_write(9), regmap_noinc_write(9)
• regmap_field_update_bits_base(9), regmap_field_test_bits(9), regmap_fields_update_bits_base(9), regmap_bulk_write(9), regmap_multi_reg_write(9), regmap_multi_reg_write_bypassed(9), regmap_raw_write_async(9)
• regmap_read(9), regmap_read_bypassed(9), regmap_raw_read(9), regmap_noinc_read(9), regmap_field_read(9), regmap_fields_read(9), regmap_bulk_read(9), regmap_multi_reg_read(9)
• regmap_update_bits_base(9), regmap_test_bits(9), regmap_async_complete(9), regmap_register_patch(9)
• regmap_get_val_bytes(9), regmap_get_max_register(9), regmap_get_reg_stride(9), regmap_might_sleep(9)

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ngl the entire read/write/free/alloc cinematic universe is right there in SEE ALSO, so if you ever feel like you're writing to the wrong granularity, that's your sign to go browse 🧚

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and that's the page!! 🌈 this one's sourced from ./drivers/base/regmap and dated October 2026 — so like, future-dated queen 👑💀 go write some registers, i'm obsessed with you, byeee 🍓💖