iio: magnetometer: ak8975: ensure device is awake for buffered capture

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Currently, the ak8975_start_read_axis() can be called while the device
is autosuspended, causing two issues:

1. I2C transfers in the aforementioned function will fail or timeout
because ak8975_runtime_suspend() disables the device regulators.
2. Since ak8975_fill_buffer() does not hold runtime references,
ak8975_runtime_suspend() can run concurrently, and since PM callbacks
do not use a locking mechanism, it may cause a race accessing the
control register via the I2C bus.

Fix this issue by adding struct iio_buffer_setup_ops that contains
preenable and postdisable functions to ensure correct that device is
powered on when running a buffered capture.

Fixes: bc11ca4a0b ("iio:magnetometer:ak8975: triggered buffer support")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260511-magnetometer-fixes-post-pickup-v7-0-9d910faa28b6%40gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

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Joshua Crofts 2026-05-13 16:35:52 +02:00 • committed by Jonathan Cameron

parent 8bf3e7a9de

commit eaead586b3

1 changed files with 23 additions and 1 deletions

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drivers/iio/magnetometer/ak8975.c

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