[PATCH 1/1] docs: iio: add documentation for adis16475 driver
From: Ramona Gradinariu
Date: Tue Jan 23 2024 - 05:47:48 EST
Add documentation for adis16475 driver which describes
the driver device files and shows how the user may use the
ABI for various scenarios (configuration, measurement, etc.).
Signed-off-by: Ramona Gradinariu <ramona.gradinariu@xxxxxxxxxx>
---
Documentation/iio/adis16475.rst | 327 ++++++++++++++++++++++++++++++++
1 file changed, 327 insertions(+)
create mode 100644 Documentation/iio/adis16475.rst
diff --git a/Documentation/iio/adis16475.rst b/Documentation/iio/adis16475.rst
new file mode 100644
index 000000000000..9af054f4af79
--- /dev/null
+++ b/Documentation/iio/adis16475.rst
@@ -0,0 +1,327 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+================
+ADIS16475 driver
+================
+
+This driver supports Analog Device's IMUs on SPI bus.
+
+1. Supported devices
+====================
+
+* `ADIS16465 <https://www.analog.com/ADIS16465>`_
+* `ADIS16467 <https://www.analog.com/ADIS16467>`_
+* `ADIS16470 <https://www.analog.com/ADIS16470>`_
+* `ADIS16475 <https://www.analog.com/ADIS16475>`_
+* `ADIS16477 <https://www.analog.com/ADIS16477>`_
+* `ADIS16500 <https://www.analog.com/ADIS16500>`_
+* `ADIS16505 <https://www.analog.com/ADIS16505>`_
+* `ADIS16507 <https://www.analog.com/ADIS16507>`_
+
+Each supported device is a precision, miniature microelectromechanical system
+(MEMS) inertial measurement unit (IMU) that includes a triaxial gyroscope and a
+triaxial accelerometer. Each inertial sensor in the IMU device combines with
+signal conditioning that optimizes dynamic performance. The factory calibration
+characterizes each sensor for sensitivity, bias, alignment, linear acceleration
+(gyroscope bias), and point of percussion (accelerometer location). As a result,
+each sensor has dynamic compensation formulas that provide accurate sensor
+measurements over a broad set of conditions.
+
+2. Device attributes
+====================
+
+Accelerometer, gyroscope measures are always provided. Furthermore, the driver
+offers the capability to retrieve the delta angle and the delta velocity
+measurements computed by the device.
+
+The delta angle measurements represent a calculation of angular displacement
+between each sample update, while the delta velocity measurements represent a
+calculation of linear velocity change between each sample update.
+
+Finally, temperature data are provided which show a coarse measurement of
+the temperature inside of the IMU device. This data is most useful for
+monitoring relative changes in the thermal environment.
+
+The signal chain of each inertial sensor (accelerometers and
+gyroscopes) includes the application of unique correction
+formulas, which are derived from extensive characterization
+of bias, sensitivity, alignment, response to linear acceleration
+(gyroscopes), and point of percussion (accelerometer location)
+over a temperature range of −40°C to +85°C, for each ADIS device.
+These correction formulas are not accessible, but users do have
+the opportunity to adjust the bias for each sensor individually
+through the calibbias attribute.
+
++-------------------------------------------+----------------------------------------------------------+
+| 3-Axis Accelerometer related device files | Description |
++-------------------------------------------+----------------------------------------------------------+
+| in_accel_scale | Scale for the accelerometer channels. |
++-------------------------------------------+----------------------------------------------------------+
+| in_accel_x_calibbias | Calibration offset for the X-axis accelerometer channel. |
++-------------------------------------------+----------------------------------------------------------+
+| accel_calibbias_x | x-axis acceleration offset correction |
++-------------------------------------------+----------------------------------------------------------+
+| in_accel_x_raw | Raw X-axis accelerometer channel value. |
++-------------------------------------------+----------------------------------------------------------+
+| accel_calibbias_y | y-axis acceleration offset correction |
++-------------------------------------------+----------------------------------------------------------+
+| in_accel_y_raw | Raw Y-axis accelerometer channel value. |
++-------------------------------------------+----------------------------------------------------------+
+| in_accel_z_calibbias | Calibration offset for the Z-axis accelerometer channel. |
++-------------------------------------------+----------------------------------------------------------+
+| in_accel_z_raw | Raw Z-axis accelerometer channel value. |
++-------------------------------------------+----------------------------------------------------------+
+| in_deltavelocity_scale | Scale for delta velocity channels. |
++-------------------------------------------+----------------------------------------------------------+
+| in_deltavelocity_x_raw | Raw X-axis delta velocity channel value. |
++-------------------------------------------+----------------------------------------------------------+
+| in_deltavelocity_y_raw | Raw Y-axis delta velocity channel value. |
++-------------------------------------------+----------------------------------------------------------+
+| in_deltavelocity_z_raw | Raw Z-axis delta velocity channel value. |
++-------------------------------------------+----------------------------------------------------------+
+
++---------------------------------------+------------------------------------------------------+
+| 3-Axis Gyroscope related device files | Description |
++---------------------------------------+------------------------------------------------------+
+| in_anglvel_scale | Scale for the gyroscope channels. |
++---------------------------------------+------------------------------------------------------+
+| in_anglvel_x_calibbias | Calibration offset for the X-axis gyroscope channel. |
++---------------------------------------+------------------------------------------------------+
+| anglvel_calibbias_x | x-axis gyroscope offset correction |
++---------------------------------------+------------------------------------------------------+
+| in_anglvel_x_raw | Raw X-axis gyroscope channel value. |
++---------------------------------------+------------------------------------------------------+
+| anglvel_calibbias_y | y-axis gyroscope offset correction |
++---------------------------------------+------------------------------------------------------+
+| in_anglvel_y_raw | Raw Y-axis gyroscope channel value. |
++---------------------------------------+------------------------------------------------------+
+| in_anglvel_z_calibbias | Calibration offset for the Z-axis gyroscope channel. |
++---------------------------------------+------------------------------------------------------+
+| in_anglvel_z_raw | Raw Z-axis gyroscope channel value. |
++---------------------------------------+------------------------------------------------------+
+| in_deltaangl_scale | Scale for delta angle channels. |
++---------------------------------------+------------------------------------------------------+
+| in_deltaangl_x_raw | Raw X-axis delta angle channel value. |
++---------------------------------------+------------------------------------------------------+
+| in_deltaangl_y_raw | Raw Y-axis delta angle channel value. |
++---------------------------------------+------------------------------------------------------+
+| in_deltaangl_z_raw | Raw Z-axis delta angle channel value. |
++---------------------------------------+------------------------------------------------------+
+
++----------------------------------+-------------------------------------------+
+| Temperature sensor related files | Description |
++----------------------------------+-------------------------------------------+
+| in_temp0_raw | Raw temperature channel value. |
++----------------------------------+-------------------------------------------+
+| in_temp0_scale | Scale for the temperature sensor channel. |
++----------------------------------+-------------------------------------------+
+
++-------------------------------+---------------------------------------------------------+
+| Miscellaneous device files | Description |
++-------------------------------+---------------------------------------------------------+
+| name | Name of the IIO device. |
++-------------------------------+---------------------------------------------------------+
+| sampling_frequency | Currently selected sample rate. |
++-------------------------------+---------------------------------------------------------+
+| filter_low_pass_3db_frequency | Bandwidth for the accelerometer and gyroscope channels. |
++-------------------------------+---------------------------------------------------------+
+
++----------------------+-------------------------------------------------------------------------+
+| Debugfs device files | Description |
++----------------------+-------------------------------------------------------------------------+
+| serial_number | The serial number of the chip in hexadecimal format. |
++----------------------+-------------------------------------------------------------------------+
+| product_id | Chip specific product id (e.g. 16475, 16500, 16505, etc.). |
++----------------------+-------------------------------------------------------------------------+
+| flash_count | The number of flash writes performed on the device. |
++----------------------+-------------------------------------------------------------------------+
+| firmware_revision | String containing the firmware revision in the following format ##.##. |
++----------------------+-------------------------------------------------------------------------+
+| firmware_date | String containing the firmware date in the following format mm-dd-yyyy. |
++----------------------+-------------------------------------------------------------------------+
+
+Usage examples
+--------------
+
+Show device name:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat name
+ adis16505-2
+
+Show accelerometer channels value:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_raw
+ -275924
+ root:/sys/bus/iio/devices/iio:device0> cat in_accel_y_raw
+ -30142222
+ root:/sys/bus/iio/devices/iio:device0> cat in_accel_z_raw
+ 261265769
+ root:/sys/bus/iio/devices/iio:device0> cat in_accel_scale
+ 0.000000037
+
+- X-axis acceleration = in_accel_x_raw * in_accel_scale = −0.010209188 m/s^2
+- Y-axis acceleration = in_accel_y_raw * in_accel_scale = −1.115262214 m/s^2
+- Z-axis acceleration = in_accel_z_raw * in_accel_scale = 9.666833453 m/s^2
+
+Show gyroscope channels value:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_x_raw
+ -3324626
+ root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_y_raw
+ 1336980
+ root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_z_raw
+ -602983
+ root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_scale
+ 0.000000006
+
+- X-axis angular velocity = in_anglvel_x_raw * in_anglvel_scale = −0.019947756 rad/s
+- Y-axis angular velocity = in_anglvel_y_raw * in_anglvel_scale = 0.00802188 rad/s
+- Z-axis angular velocity = in_anglvel_z_raw * in_anglvel_scale = −0.003617898 rad/s
+
+Set calibration offset for accelerometer channels:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
+ 0
+
+ root:/sys/bus/iio/devices/iio:device0> echo 5000 > in_accel_x_calibbias
+ root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
+ 5000
+
+Set calibration offset for gyroscope channels:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_y_calibbias
+ 0
+
+ root:/sys/bus/iio/devices/iio:device0> echo -5000 > in_anglvel_y_calibbias
+ root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_y_calibbias
+ -5000
+
+Set sampling frequency:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency
+ 2000.000000
+
+ root:/sys/bus/iio/devices/iio:device0> echo 1000 > sampling_frequency
+ 1000.000000
+
+Set bandwidth for accelerometer and gyroscope:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat filter_low_pass_3db_frequency
+ 720
+
+ root:/sys/bus/iio/devices/iio:device0> echo 360 > filter_low_pass_3db_frequency
+ root:/sys/bus/iio/devices/iio:device0> cat filter_low_pass_3db_frequency
+ 360
+
+Show serial number:
+
+.. code-block:: bash
+
+ root:/sys/kernel/debug/iio/iio:device0> cat serial_number
+ 0x04f9
+
+Show product id:
+
+.. code-block:: bash
+
+ root:/sys/kernel/debug/iio/iio:device0> cat product_id
+ 16505
+
+Show flash count:
+
+.. code-block:: bash
+
+ root:/sys/kernel/debug/iio/iio:device0> cat flash_count
+ 150
+
+Show firmware revision:
+
+.. code-block:: bash
+
+ root:/sys/kernel/debug/iio/iio:device0> cat firmware_revision
+ 1.6
+
+Show firmware date:
+
+.. code-block:: bash
+
+ root:/sys/kernel/debug/iio/iio:device0> cat firmware_date
+ 06-27-2019
+
+
+Device buffers
+==============
+
+This driver supports IIO buffers.
+
+All devices support retrieving the raw acceleration, gyroscope and temperature measurements using buffers.
+
+The following device families also support retrieving the delta velocity, delta angle and temperature measurements using buffers:
+ - ADIS16477
+ - ADIS16500
+ - ADIS16505
+ - ADIS16507
+
+However, when retrieving acceleration or gyroscope data using buffers, delta readings will not be available and vice versa.
+
+Usage examples
+--------------
+
+Set trigger if not available:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> cat trigger/current_trigger
+
+ root:/sys/bus/iio/devices/iio:device0> echo adis16505-2-dev0 > trigger/current_trigger
+ root:/sys/bus/iio/devices/iio:device0> cat trigger/current_trigger
+ adis16505-2-dev0
+
+Select channels for buffer read:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_deltavelocity_x_en
+ root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_deltavelocity_y_en
+ root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_deltavelocity_z_en
+ root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_temp0_en
+
+Set the number of samples to be stored in the buffer:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> echo 10 > buffer/length
+
+Enable buffer readings:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> echo 1 > buffer/enable
+
+Obtain buffered data:
+
+.. code-block:: bash
+
+ root:/sys/bus/iio/devices/iio:device0> hexdump /dev/iio\:device0
+ ...
+ 0044760 3901 0000 ffff f9fe ffff 29ee 0100 f79b
+ 0044770 3901 0000 ffff 98fe ffff 1aef 0100 439a
+ 0044780 3901 0000 ffff b4fe ffff 32ef 0100 c199
+ 0044790 3901 0000 ffff bdfe ffff 20ef 0100 5f9a
+ 00447a0 3901 0000 ffff 37ff ffff 1eef 0100 389b
+ 00447b0 3901 0000 ffff 7dff ffff 96ee 0100 5a9c
+ ...
--
2.34.1