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+What: /sys/bus/iio/devices/iio:deviceX/in_count0_preset
+KernelVersion: 4.13
+Contact: fabrice.gasnier@st.com
+Description:
+ Reading returns the current preset value. Writing sets the
+ preset value. Encoder counts continuously from 0 to preset
+ value, depending on direction (up/down).
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
+KernelVersion: 4.13
+Contact: fabrice.gasnier@st.com
+Description:
+ Reading returns the list possible quadrature modes.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count0_quadrature_mode
+KernelVersion: 4.13
+Contact: fabrice.gasnier@st.com
+Description:
+ Configure the device counter quadrature modes:
+ - non-quadrature:
+ Encoder IN1 input servers as the count input (up
+ direction).
+ - quadrature:
+ Encoder IN1 and IN2 inputs are mixed to get direction
+ and count.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count_polarity_available
+KernelVersion: 4.13
+Contact: fabrice.gasnier@st.com
+Description:
+ Reading returns the list possible active edges.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count0_polarity
+KernelVersion: 4.13
+Contact: fabrice.gasnier@st.com
+Description:
+ Configure the device encoder/counter active edge:
+ - rising-edge
+ - falling-edge
+ - both-edges
+
+ In non-quadrature mode, device counts up on active edge.
+ In quadrature mode, encoder counting scenarios are as follows:
+ ----------------------------------------------------------------
+ | Active | Level on | IN1 signal | IN2 signal |
+ | edge | opposite |------------------------------------------
+ | | signal | Rising | Falling | Rising | Falling |
+ ----------------------------------------------------------------
+ | Rising | High -> | Down | - | Up | - |
+ | edge | Low -> | Up | - | Down | - |
+ ----------------------------------------------------------------
+ | Falling | High -> | - | Up | - | Down |
+ | edge | Low -> | - | Down | - | Up |
+ ----------------------------------------------------------------
+ | Both | High -> | Down | Up | Up | Down |
+ | edges | Low -> | Up | Down | Down | Up |
+ ----------------------------------------------------------------