Re: [PATCH v2] iio: accel: adxl372: Add timestamp to FIFO data

[Md Shofiqul Islam <shofiqtest@gmail.com>]

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Hi Stepan,

Thank you for the careful analysis. You are correct -- iio_push_to_buffers_with_ts()
writes the s64 timestamp into the source buffer at offset ALIGN(data_sz - 8, 8),
which in the FIFO drain loop means the write lands in data that has not been
consumed by the next iteration yet. This is indeed a data corruption bug.

v3 switches to iio_push_to_buffers_with_ts_unaligned() which copies the sample
into an internal bounce buffer before adding the timestamp, leaving fifo_buf[]
untouched across iterations. The size argument stays as
st->fifo_set_size * sizeof(__be16) -- the actual per-sample data size -- which
_unaligned() clamps internally to min(scan_bytes, data_sz).

The fix and the explanation of why _unaligned() is needed are in the commit
message of v3:
  [PATCH v3] iio: accel: adxl372: Add timestamp to FIFO data
  Message-ID: <20260517091735.135610-1-shofiqtest@gmail.com>

Thanks again for catching this.

Md Shofiqul Islam