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
