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lf-6.6.y
linux-imx/Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector
Mauro Carvalho Chehab 3443333284 docs: ABI: testing: make the files compatible with ReST output 
Some files over there won't parse well by Sphinx.

Fix them.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for IIO
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/58cf3c2d611e0197fb215652719ebd82ca2658db.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-30 13:07:01 +01:00

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What: /sys/bus/iio/devices/iio:deviceX/in_altvoltageY_invert Date: October 2016 KernelVersion: 4.9 Contact: Peter Rosin peda@axentia.se Description: The DAC is used to find the peak level of an alternating voltage input signal by a binary search using the output of a comparator wired to an interrupt pin. Like so::

	                           _
	                          | \
	     input +------>-------|+ \
	                          |   \
	            .-------.     |    }---.
	            |       |     |   /    |
	            |    dac|-->--|- /     |
	            |       |     |_/      |
	            |       |              |
	            |       |              |
	            |    irq|------<-------'
	            |       |
	            '-------'

	The boolean invert attribute (0/1) should be set when the
	input signal is centered around the maximum value of the
	dac instead of zero. The envelope detector will search
	from below in this case and will also invert the result.

	The edge/level of the interrupt is also switched to its
	opposite value.

What: /sys/bus/iio/devices/iio:deviceX/in_altvoltageY_compare_interval Date: October 2016 KernelVersion: 4.9 Contact: Peter Rosin peda@axentia.se Description: Number of milliseconds to wait for the comparator in each step of the binary search for the input peak level. Needs to relate to the frequency of the input signal.