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Diffstat (limited to 'Documentation/iio/ad7606.rst')
| -rw-r--r-- | Documentation/iio/ad7606.rst | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/Documentation/iio/ad7606.rst b/Documentation/iio/ad7606.rst index 930199e03c67..5e02516bab40 100644 --- a/Documentation/iio/ad7606.rst +++ b/Documentation/iio/ad7606.rst @@ -26,6 +26,35 @@ SPI wiring modes These ADCs can output data on several SDO lines (1/2/4/8). The driver currently supports only 1 SDO line. +SPI offload wiring +------------------ +When used with a SPI offload, the supported wiring configuration is: + +.. code-block:: + + +-------------+ +-------------+ + | BUSY |-------->| TRIGGER | + | CS |<--------| CS | + | | | | + | ADC | | SPI | + | | | | + | SDI |<--------| SDO | + | DOUTA |-------->| SDI | + | SCLK |<--------| SCLK | + | | | | + | | +-------------+ + | CONVST |<--------| PWM | + +-------------+ +-------------+ + +In this case, the ``pwms`` property is required. +The ``#trigger-source-cells = <1>`` property is also required to connect back +to the SPI offload. The SPI offload will have ``trigger-sources`` property +with a cell to indicate the busy signal: +``<&ad7606 AD4695_TRIGGER_EVENT_BUSY>``. + +.. seealso:: `SPI offload support`_ + + Parallel wiring mode -------------------- @@ -123,6 +152,22 @@ Unimplemented features - CRC indication - Calibration +SPI offload support +=================== + +To be able to achieve the maximum sample rate, the driver can be used with the +`AXI SPI Engine`_ to provide SPI offload support. + +.. _AXI SPI Engine: https://analogdevicesinc.github.io/hdl/library/spi_engine/index.html + +When SPI offload is being used, some attributes will be different. + +* ``trigger`` directory is removed. +* ``sampling_frequency`` attribute is added for setting the sample rate. +* ``timestamp`` channel is removed. +* Buffer data format may be different compared to when offload is not used, + e.g. the ``in_voltage0_type`` attribute. + Device buffers ============== |