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+What: /sys/bus/iio/devices/iio:deviceX/in_count_count_direction_available
+What: /sys/bus/iio/devices/iio:deviceX/in_count_count_mode_available
+What: /sys/bus/iio/devices/iio:deviceX/in_count_noise_error_available
+What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
+What: /sys/bus/iio/devices/iio:deviceX/in_index_index_polarity_available
+What: /sys/bus/iio/devices/iio:deviceX/in_index_synchronous_mode_available
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Discrete set of available values for the respective counter
+ configuration are listed in this file.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_countY_count_direction
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates whether the counter for
+ channel Y is counting up or down.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_countY_count_mode
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Count mode for channel Y. Four count modes are available:
+ normal, range limit, non-recycle, and modulo-n. The preset value
+ for channel Y is used by the count mode where required.
+
+ Normal:
+ Counting is continuous in either direction.
+
+ Range Limit:
+ An upper or lower limit is set, mimicking limit switches
+ in the mechanical counterpart. The upper limit is set to
+ the preset value, while the lower limit is set to 0. The
+ counter freezes at count = preset when counting up, and
+ at count = 0 when counting down. At either of these
+ limits, the counting is resumed only when the count
+ direction is reversed.
+
+ Non-recycle:
+ Counter is disabled whenever a 24-bit count overflow or
+ underflow takes place. The counter is re-enabled when a
+ new count value is loaded to the counter via a preset
+ operation or write to raw.
+
+ Modulo-N:
+ A count boundary is set between 0 and the preset value.
+ The counter is reset to 0 at count = preset when
+ counting up, while the counter is set to the preset
+ value at count = 0 when counting down; the counter does
+ not freeze at the bundary points, but counts
+ continuously throughout.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_countY_noise_error
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Read-only attribute that indicates whether excessive noise is
+ present at the channel Y count inputs in quadrature clock mode;
+ irrelevant in non-quadrature clock mode.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_countY_preset
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ If the counter device supports preset registers, the preset
+ count for channel Y is provided by this attribute.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_countY_quadrature_mode
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Configure channel Y counter for non-quadrature or quadrature
+ clock mode. Selecting non-quadrature clock mode will disable
+ synchronous load mode. In quadrature clock mode, the channel Y
+ scale attribute selects the encoder phase division (scale of 1
+ selects full-cycle, scale of 0.5 selects half-cycle, scale of
+ 0.25 selects quarter-cycle) processed by the channel Y counter.
+
+ Non-quadrature:
+ The filter and decoder circuit are bypassed. Encoder A
+ input serves as the count input and B as the UP/DOWN
+ direction control input, with B = 1 selecting UP Count
+ mode and B = 0 selecting Down Count mode.
+
+ Quadrature:
+ Encoder A and B inputs are digitally filtered and
+ decoded for UP/DN clock.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_countY_set_to_preset_on_index
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Whether to set channel Y counter with channel Y preset value
+ when channel Y index input is active, or continuously count.
+ Valid attribute values are boolean.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_indexY_index_polarity
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Active level of channel Y index input; irrelevant in
+ non-synchronous load mode.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_indexY_synchronous_mode
+KernelVersion: 4.9
+Contact: linux-iio@vger.kernel.org
+Description:
+ Configure channel Y counter for non-synchronous or synchronous
+ load mode. Synchronous load mode cannot be selected in
+ non-quadrature clock mode.
+
+ Non-synchronous:
+ A logic low level is the active level at this index
+ input. The index function (as enabled via
+ set_to_preset_on_index) is performed directly on the
+ active level of the index input.
+
+ Synchronous:
+ Intended for interfacing with encoder Index output in
+ quadrature clock mode. The active level is configured
+ via index_polarity. The index function (as enabled via
+ set_to_preset_on_index) is performed synchronously with
+ the quadrature clock on the active level of the index
+ input.