Add a section for alert support, explaining how user can use iio events attributes to enable alert and set thresholds. Reviewed-by: David Lechner <dlechner@xxxxxxxxxxxx> Signed-off-by: Julien Stephan <jstephan@xxxxxxxxxxxx> --- Documentation/iio/ad7380.rst | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) diff --git a/Documentation/iio/ad7380.rst b/Documentation/iio/ad7380.rst index c46127700e14ca9ec3cac0bd5776b6702f2659e2..cff688bcc2d9601a9faf42d5e9c217486639ca66 100644 --- a/Documentation/iio/ad7380.rst +++ b/Documentation/iio/ad7380.rst @@ -92,6 +92,38 @@ must restart iiod using the following command: root:~# systemctl restart iiod +Alert +----- + +2 channels variants of the ad738x family, can use the SDOB line as an alert pin +when configured in 1 SDO line mode. 4 channels variants, can use SDOD as an +alert pin when configured in 1 or 2 SDO line(s) mode, although only 1 SDO line +mode is currently supported by the driver (see `SPI wiring modes`_). + +At the end of a conversion the active-low alert pin gets asserted if the +conversion result exceeds the alert high limit or falls below the alert low +limit. It is cleared, on a falling edge of CS. The alert pin is common to all +channels. + +User can enable alert using the regular iio events attribute: + +.. code-block:: bash + + events/thresh_either_en + +The high and low thresholds are common to all channels and can also be set using +regular iio events attributes: + +.. code-block:: bash + + events/in_thresh_falling_value + events/in_thresh_rising_value + +If debugfs is available, user can read the ALERT register to determine the +faulty channel and direction. + +In most use cases, user will hardwire the alert pin to trigger a shutdown. + Channel selection and sequencer (single-end chips only) ------------------------------------------------------- @@ -144,7 +176,6 @@ Unimplemented features - Rolling average oversampling - Power down mode - CRC indication -- Alert Device buffers -- 2.47.1
