iio_read_acpi_mount_matrix(9)

💖 iio_read_acpi_mount_matrix(9) 💖

okay so bestie, welcome to the Kernel API Manual ✨ — today's main character is iio_read_acpi_mount_matrix, and no cap, it's lowkey iconic: it goes digging through ACPI firmware to find out which way your accelerometer is literally facing. 🧭🦋

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✨ NAME ✨

iio_read_acpi_mount_matrix — read accelerometer mount matrix info from ACPI 🎀

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🌸 SYNOPSIS 🌸

bool iio_read_acpi_mount_matrix (struct device *dev , struct
iio_mount_matrix *orientation , char *acpi_method );

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💅 ARGUMENTS 💅

• dev — the device structure, obvs. the thing we're asking about 🫶
• orientation — an iio_mount_matrix struct that this function fills in for you. it's giving "empty cup, hand me the facts" ☕✨
• acpi_method — the ACPI method name we read the matrix from, usually "ROTM" 👑

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🔥 DESCRIPTION 🔥

So the whole vibe: this function tries to read the mount-matrix by calling the method you named on the device's ACPI firmware-node. That's it, that's the mission. 🚀

Now the dramatic part 😭 — if the device has no ACPI firmware-node, or the method doesn't exist, then this will fail silently. no error, no drama, just vibes and a quiet false. not me finding out the hard way 💀

It expects the method to hand back data in the ACPI "ROTM" format defined by Microsoft: https://learn.microsoft.com/en-us/windows-hardware/drivers/sensors/sensors-acpi-entries

⚠️ heads up bestie: this is a Microsoft extension and it is not part of the official ACPI spec. so like, it's real, it works, but it's not canon. 🙈

And why is acpi_method a parameter instead of just hardcoding it, you ask? because some dual-accel setups define 2 mount matrices inside a single ACPI device, using separate "ROMK" and "ROMS" methods. so yeah, configurable on purpose. slay for flexibility 💐

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⭐ RETURN ⭐

true if the matrix was read successfully, false otherwise. that's the whole tea 🍵

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🦋 SEE ALSO 🦋

• Kernel file ./drivers/iio/industrialio-acpi.c
• iio_get_acpi_device_name_and_data(9)

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🌈 okay that's the page!! this one lives under ./drivers/iio, dated October 2026, and it's part of the Kernel API Manual — ty for reading bestie, you ate that, periodt 💖🎀🧚‍♀️