regmap_field...poll_timeout(9)

💅 regmap_field_read_poll_timeout — Kernel API Manual ✨

okay so bestie, this is a kernel API page, and the function we're obsessing over is literally regmap_field_read_poll_timeout. Yeah that's a mouthful, she ate though. 🎀

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✨ NAME ✨

regmap_field_read_poll_timeout — poll until a condition is met or timeout. that's it, that's the vibe check 🦋

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🌸 SYNOPSIS 🌸

regmap_field_read_poll_timeout (field , val , cond , sleep_us , timeout_us );

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💖 ARGUMENTS 💖

• field — the regmap field you're reading from. your main character. 👑
• val — an unsigned integer variable, and the value gets read into it. she's the destination, no cap.
• cond — the break condition, and yeah it usually involves val. like, that's the whole point bestie 😭
• sleep_us — maximum time to sleep between reads, in us. 0 means tight-loops, which, ok, no rest for the wicked 💀. ngl please go read the usleep_range function description for the details and limitations — fr fr, don't skip it.
• timeout_us — timeout in us. 0 means never timeout, she waits forever 🫶

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🌈 DESCRIPTION 🌈

This one is modelled after the readx_poll_timeout macros over in linux/iopoll.h. that's the lore 🧚

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⭐ RETURN ⭐

• 0 on success — slay 💅
• -ETIMEDOUT upon a timeout
• or the regmap_field_read error return value in case of an error read 🙈

and in the two former cases (timeout and error read), the last read value at addr is stored in val. iconic behaviour honestly.

⚠️ must not be called from atomic context if sleep_us or timeout_us are used. like seriously, do not, that's the danger zone 💀🔥

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🦋 SEE ALSO 🦋

Kernel file ./include/linux/regmap.h — and the whole friend group:

• struct reg_default(9)
• struct reg_sequence(9)
• regmap_read_poll_timeout(9)
• regmap_read_poll_timeout_atomic(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_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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okay that's the whole page, you're welcome 💖✨

signed off with love from ./include/linux, dated October 2026 — iykyk 🎀🦋