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521dbebf70
Move counting direction documentation for 104-quad-8 to sysfs-bus-iio to avoid duplicated for other incoming drivers Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
118 lines
4.5 KiB
Plaintext
118 lines
4.5 KiB
Plaintext
What: /sys/bus/iio/devices/iio:deviceX/in_count_count_mode_available
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What: /sys/bus/iio/devices/iio:deviceX/in_count_noise_error_available
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What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
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What: /sys/bus/iio/devices/iio:deviceX/in_index_index_polarity_available
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What: /sys/bus/iio/devices/iio:deviceX/in_index_synchronous_mode_available
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Discrete set of available values for the respective counter
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configuration are listed in this file.
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What: /sys/bus/iio/devices/iio:deviceX/in_countY_count_mode
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Count mode for channel Y. Four count modes are available:
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normal, range limit, non-recycle, and modulo-n. The preset value
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for channel Y is used by the count mode where required.
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Normal:
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Counting is continuous in either direction.
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Range Limit:
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An upper or lower limit is set, mimicking limit switches
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in the mechanical counterpart. The upper limit is set to
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the preset value, while the lower limit is set to 0. The
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counter freezes at count = preset when counting up, and
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at count = 0 when counting down. At either of these
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limits, the counting is resumed only when the count
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direction is reversed.
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Non-recycle:
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Counter is disabled whenever a 24-bit count overflow or
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underflow takes place. The counter is re-enabled when a
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new count value is loaded to the counter via a preset
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operation or write to raw.
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Modulo-N:
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A count boundary is set between 0 and the preset value.
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The counter is reset to 0 at count = preset when
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counting up, while the counter is set to the preset
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value at count = 0 when counting down; the counter does
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not freeze at the bundary points, but counts
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continuously throughout.
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What: /sys/bus/iio/devices/iio:deviceX/in_countY_noise_error
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Read-only attribute that indicates whether excessive noise is
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present at the channel Y count inputs in quadrature clock mode;
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irrelevant in non-quadrature clock mode.
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What: /sys/bus/iio/devices/iio:deviceX/in_countY_preset
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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If the counter device supports preset registers, the preset
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count for channel Y is provided by this attribute.
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What: /sys/bus/iio/devices/iio:deviceX/in_countY_quadrature_mode
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Configure channel Y counter for non-quadrature or quadrature
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clock mode. Selecting non-quadrature clock mode will disable
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synchronous load mode. In quadrature clock mode, the channel Y
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scale attribute selects the encoder phase division (scale of 1
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selects full-cycle, scale of 0.5 selects half-cycle, scale of
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0.25 selects quarter-cycle) processed by the channel Y counter.
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Non-quadrature:
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The filter and decoder circuit are bypassed. Encoder A
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input serves as the count input and B as the UP/DOWN
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direction control input, with B = 1 selecting UP Count
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mode and B = 0 selecting Down Count mode.
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Quadrature:
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Encoder A and B inputs are digitally filtered and
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decoded for UP/DN clock.
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What: /sys/bus/iio/devices/iio:deviceX/in_countY_set_to_preset_on_index
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Whether to set channel Y counter with channel Y preset value
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when channel Y index input is active, or continuously count.
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Valid attribute values are boolean.
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What: /sys/bus/iio/devices/iio:deviceX/in_indexY_index_polarity
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Active level of channel Y index input; irrelevant in
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non-synchronous load mode.
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What: /sys/bus/iio/devices/iio:deviceX/in_indexY_synchronous_mode
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KernelVersion: 4.10
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Contact: linux-iio@vger.kernel.org
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Description:
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Configure channel Y counter for non-synchronous or synchronous
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load mode. Synchronous load mode cannot be selected in
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non-quadrature clock mode.
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Non-synchronous:
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A logic low level is the active level at this index
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input. The index function (as enabled via
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set_to_preset_on_index) is performed directly on the
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active level of the index input.
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Synchronous:
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Intended for interfacing with encoder Index output in
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quadrature clock mode. The active level is configured
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via index_polarity. The index function (as enabled via
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set_to_preset_on_index) is performed synchronously with
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the quadrature clock on the active level of the index
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input.
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