iio_backend_ext_info_set(9)

🌸 NAME 🌸

okay so bestie, welcome to the Kernel API Manual page for iio_backend_ext_info_set — it's the IIO ext_info write callback and honestly it's giving "quiet helper that does the important thing." 💅

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✨ SYNOPSIS ✨

ssize_t iio_backend_ext_info_set (struct iio_dev *indio_dev , uintptr_t
       private , const struct iio_chan_spec *chan , const char *buf , size_t
       len );

copy that signature exactly bestie, no creative editing, I'm begging 🙈

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🫶 ARGUMENTS 🫶

• indio_dev — the IIO device. the main character, lowkey.
• private — data that's private to the driver. not for sharing, it's on a need-to-know basis 💜
• chan — the IIO channel. the lil lane your data travels on.
• buf — the buffer holding the sysfs attribute. this is where the text actually lives 🎀
• len — the length of that buffer. numbers matter, periodt.

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🦋 DESCRIPTION 🦋

so here's the vibe: this helper is intended to be used by backends that extend an IIO channel — you do that through iio_backend_extend_chan_spec — and add extended info while you're at it. ✨

in that situation, backends are not supposed to give their own callbacks. why? because they would not have a way to get the backend from indio_dev. like, no path home. no cap. 😭

and this one? this is the setter. the one that writes. the queen of the pair, iykyk 👑

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💀 RETURN 💀

• Buffer length on success 🎉
• a negative error number on failure 😭

that's it, that's the whole mood. no in-between, no "it depends."

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🔥 SEE ALSO 🔥

first up, the actual kernel file, go read it:

• ./drivers/iio/industrialio-backend.c

and now the whole squad, everybody say hi 👋:

• iio_backend_debugfs_add(9)
• iio_backend_debugfs_print_chan_status(9)
• iio_backend_chan_enable(9)
• iio_backend_chan_disable(9)
• iio_backend_disable(9)
• iio_backend_enable(9)
• devm_iio_backend_enable(9)
• iio_backend_data_format_set(9)
• iio_backend_data_source_set(9)
• iio_backend_data_source_get(9)
• iio_backend_set_sampling_freq(9)
• iio_backend_test_pattern_set(9)
• iio_backend_chan_status(9)
• iio_backend_iodelay_set(9)
• iio_backend_data_sample_trigger(9)
• devm_iio_backend_request_buffer(9)
• iio_backend_read_raw(9)
• iio_backend_ext_info_get(9)
• iio_backend_interface_type_get(9)
• iio_backend_data_size_set(9)
• iio_backend_oversampling_ratio_set(9)
• iio_backend_extend_chan_spec(9)
• iio_backend_has_caps(9)
• iio_backend_filter_type_set(9)
• iio_backend_interface_data_align(9)
• iio_backend_num_lanes_set(9)
• iio_backend_ddr_enable(9)
• iio_backend_ddr_disable(9)
• iio_backend_data_stream_enable(9)
• iio_backend_data_stream_disable(9)
• iio_backend_data_transfer_addr(9)
• devm_iio_backend_get(9)
• devm_iio_backend_get_by_index(9)
• devm_iio_backend_fwnode_get(9)
• __devm_iio_backend_get_from_fwnode_lookup(9)
• iio_backend_get_priv(9)
• devm_iio_backend_register(9)

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okay that's the page!! 🎀 this lovely thing lives down in ./drivers/iio and it's dated October 2026 — so go forth, write your ext_info, and slay. mwah 💖💅✨