Add documentation for adis16550 driver which describes the driver device files and shows how the user may use the ABI for various scenarios (configuration, measurement, etc.). Co-developed-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> Signed-off-by: Ramona Gradinariu <ramona.gradinariu@xxxxxxxxxx> Signed-off-by: Robert Budai <robert.budai@xxxxxxxxxx> --- v2: - signed of by submitter Documentation/iio/adis16550.rst | 389 ++++++++++++++++++++++++++++++++ Documentation/iio/index.rst | 1 + 2 files changed, 390 insertions(+) create mode 100644 Documentation/iio/adis16550.rst diff --git a/Documentation/iio/adis16550.rst b/Documentation/iio/adis16550.rst new file mode 100644 index 000000000000..fde38060f8fe --- /dev/null +++ b/Documentation/iio/adis16550.rst @@ -0,0 +1,389 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================ +ADIS16550 driver +================ + +This driver supports Analog Device's IMUs on SPI bus. + +1. Supported devices +==================== + +* `ADIS16550 <https://www.analog.com/ADIS16550>`_ + +The ADIS16550 is a complete inertial system that includes a triaxis gyroscope +and a triaxis accelerometer. Each inertial sensor in the ADIS16550 combines +industry leading MEMS only technology with signal conditioning that optimizes +dynamic performance. The factory calibration characterizes each sensor for +sensitivity, bias, and alignment. As a result, each sensor has its own dynamic +compensation formulas that provide accurate sensor measurements. + +The ADIS16550 provides a simple, cost-effective method for integrating accurate, +multiaxis inertial sensing into industrial systems, especially when compared +with the complexity and investment associated with discrete designs. All +necessary motion testing and calibration are part of the production process at +the factory, greatly reducing system integration time. Tight orthogonal +alignment simplifies inertial frame alignment in navigation systems. The serial +peripheral interface (SPI) and register structure provide a simple interface for +data collection and configuration control. + +2. Device attributes +==================== + +Accelerometer, gyroscope measurements 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. + +Each IIO device, has a device folder under ``/sys/bus/iio/devices/iio:deviceX``, +where X is the IIO index of the device. Under these folders reside a set of +device files, depending on the characteristics and features of the hardware +device in questions. These files are consistently generalized and documented in +the IIO ABI documentation. + +The following tables show the adis16550 related device files, found in the +specific device folder path ``/sys/bus/iio/devices/iio:deviceX``. + ++-------------------------------------------+----------------------------------------------------------+ +| 3-Axis Accelerometer related device files | Description | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_scale | Scale for the accelerometer channels. | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_filter_low_pass_3db_frequency | Bandwidth for the accelerometer channels. | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_x_calibbias | Calibration offset for the X-axis accelerometer channel. | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_x_calibscale | Calibration scale for the X-axis accelerometer channel. | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_x_raw | Raw X-axis accelerometer channel value. | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_y_calibbias | Calibration offset for the Y-axis accelerometer channel. | ++-------------------------------------------+----------------------------------------------------------+ +| in_accel_y_calibscale | Calibration scale for the Y-axis accelerometer channel. | ++-------------------------------------------+----------------------------------------------------------+ +| 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_calibscale | Calibration scale 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_filter_low_pass_3db_frequency | Scale for the gyroscope channels. | ++--------------------------------------------+------------------------------------------------------+ +| in_anglvel_x_calibbias | Calibration offset for the X-axis gyroscope channel. | ++--------------------------------------------+------------------------------------------------------+ +| in_anglvel_x_calibscale | Calibration scale for the X-axis gyroscope channel. | ++--------------------------------------------+------------------------------------------------------+ +| in_anglvel_x_raw | Raw X-axis gyroscope channel value. | ++--------------------------------------------+------------------------------------------------------+ +| in_anglvel_y_calibbias | Calibration offset for the Y-axis gyroscope channel. | ++--------------------------------------------+------------------------------------------------------+ +| in_anglvel_y_calibscale | Calibration scale for the Y-axis gyroscope channel. | ++--------------------------------------------+------------------------------------------------------+ +| 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_calibscale | Calibration scale 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_offset | Offset for the temperature sensor channel.| ++----------------------------------+-------------------------------------------+ +| 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. | ++----------------------------+--------------------------------------------------------------------------------+ +| write_lock_enable | Lock the device from further configuration. Only a reset will remove the lock. | ++----------------------------+--------------------------------------------------------------------------------+ + +The following table shows the adis16550 related device debug files, found in the +specific device debug folder path ``/sys/kernel/debug/iio/iio:deviceX``. + ++----------------------+-------------------------------------------------------------------------+ +| Debugfs device files | Description | ++----------------------+-------------------------------------------------------------------------+ +| serial_number | The serial number of the chip in hexadecimal format. | ++----------------------+-------------------------------------------------------------------------+ +| product_id | Chip specific product id (16550). | ++----------------------+-------------------------------------------------------------------------+ +| 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. | ++----------------------+-------------------------------------------------------------------------+ + +Channels processed values +------------------------- + +A channel value can be read from its _raw attribute. The value returned is the +raw value as reported by the devices. To get the processed value of the channel, +apply the following formula: + +.. code-block:: bash + + processed value = (_raw + _offset) * _scale + +Where _offset and _scale are device attributes. If no _offset attribute is +present, simply assume its value is 0. + +The adis16550 driver offers data for 5 types of channels, the table below shows +the measurement units for the processed value, which are defined by the IIO +framework: + ++--------------------------------------+---------------------------+ +| Channel type | Measurement unit | ++--------------------------------------+---------------------------+ +| Acceleration on X, Y, and Z axis | Meters per Second squared | ++--------------------------------------+---------------------------+ +| Angular velocity on X, Y and Z axis | Radians per second | ++--------------------------------------+---------------------------+ +| Delta velocity on X. Y, and Z axis | Meters per Second | ++--------------------------------------+---------------------------+ +| Delta angle on X, Y, and Z axis | Radians | ++--------------------------------------+---------------------------+ +| Temperature | Millidegrees Celsius | ++--------------------------------------+---------------------------+ + +Usage examples +-------------- + +Show device name: + +.. code-block:: bash + + root:/sys/bus/iio/devices/iio:device0> cat name + adis16550 + +Show accelerometer channels value: + +.. code-block:: bash + + root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_raw + 6903851 + root:/sys/bus/iio/devices/iio:device0> cat in_accel_y_raw + 5650550 + root:/sys/bus/iio/devices/iio:device0> cat in_accel_z_raw + 104873530 + root:/sys/bus/iio/devices/iio:device0> cat in_accel_scale + 0.000000095 + +- X-axis acceleration = in_accel_x_raw * in_accel_scale = 0.655865845 m/s^2 +- Y-axis acceleration = in_accel_y_raw * in_accel_scale = 0.53680225 m/s^2 +- Z-axis acceleration = in_accel_z_raw * in_accel_scale = 9.96298535 m/s^2 + +Show gyroscope channels value: + +.. code-block:: bash + + root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_x_raw + 193309 + root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_y_raw + -763676 + root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_z_raw + -358108 + root:/sys/bus/iio/devices/iio:device0> cat in_anglvel_scale + 0.000000003 + +- X-axis angular velocity = in_anglvel_x_raw * in_anglvel_scale = 0.000579927 rad/s +- Y-axis angular velocity = in_anglvel_y_raw * in_anglvel_scale = −0.002291028 rad/s +- Z-axis angular velocity = in_anglvel_z_raw * in_anglvel_scale = −0.001074324 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 + 4000.000000 + + root:/sys/bus/iio/devices/iio:device0> echo 1000 > sampling_frequency + 1000.000000 + +Set bandwidth for accelerometer channels: + +.. code-block:: bash + + root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency + 0 + + root:/sys/bus/iio/devices/iio:device0> echo 100 > in_accel_filter_low_pass_3db_frequency + root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency + 100 + +Show serial number: + +.. code-block:: bash + + root:/sys/kernel/debug/iio/iio:device0> cat serial_number + 0x000000b6 + +Show product id: + +.. code-block:: bash + + root:/sys/kernel/debug/iio/iio:device0> cat product_id + 16550 + +Show flash count: + +.. code-block:: bash + + root:/sys/kernel/debug/iio/iio:device0> cat flash_count + 13 + +Show firmware revision: + +.. code-block:: bash + + root:/sys/kernel/debug/iio/iio:device0> cat firmware_revision + 1.5 + +Show firmware date: + +.. code-block:: bash + + root:/sys/kernel/debug/iio/iio:device0> cat firmware_date + 28-04-2021 + +3. Device buffers +================= + +This driver supports IIO buffers. + +The device supports retrieving the raw acceleration, gyroscope, delta velocity, +delta angle and temperature measurements using buffers. + +However, when retrieving acceleration or gyroscope data using buffers, delta +readings will not be available and vice versa. This is because the device only +allows to read either acceleration and gyroscope data or delta velocity and +delta angle data at a time and switching between these two burst data selection +modes is time consuming. + +Usage examples +-------------- + +Set device trigger in current_trigger, if not already set: + +.. code-block:: bash + + root:/sys/bus/iio/devices/iio:device0> cat trigger/current_trigger + + root:/sys/bus/iio/devices/iio:device0> echo adis16550-dev0 > trigger/current_trigger + root:/sys/bus/iio/devices/iio:device0> cat trigger/current_trigger + adis16550-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 -C /dev/iio\:device0 + ... + 0000cdf0 00 00 0d 2f 00 00 08 43 00 00 09 09 00 00 a4 5f |.../...C......._| + 0000ce00 00 00 0d 2f 00 00 07 de 00 00 08 db 00 00 a4 4b |.../...........K| + 0000ce10 00 00 0d 2f 00 00 07 58 00 00 08 a3 00 00 a4 55 |.../...X.......U| + 0000ce20 00 00 0d 2f 00 00 06 d6 00 00 08 5c 00 00 a4 62 |.../.......\...b| + 0000ce30 00 00 0d 2f 00 00 06 45 00 00 08 37 00 00 a4 47 |.../...E...7...G| + 0000ce40 00 00 0d 2f 00 00 05 d4 00 00 08 30 00 00 a3 fa |.../.......0....| + 0000ce50 00 00 0d 2f 00 00 05 d0 00 00 08 12 00 00 a3 d3 |.../............| + 0000ce60 00 00 0d 2f 00 00 05 dd 00 00 08 2e 00 00 a3 e9 |.../............| + 0000ce70 00 00 0d 2f 00 00 05 cc 00 00 08 51 00 00 a3 d5 |.../.......Q....| + 0000ce80 00 00 0d 2f 00 00 05 ba 00 00 08 22 00 00 a3 9a |.../......."....| + 0000ce90 00 00 0d 2f 00 00 05 9c 00 00 07 d9 00 00 a3 40 |.../...........@| + 0000cea0 00 00 0d 2f 00 00 05 68 00 00 07 94 00 00 a2 e4 |.../...h........| + 0000ceb0 00 00 0d 2f 00 00 05 25 00 00 07 8d 00 00 a2 ce |.../...%........| + ... + +See ``Documentation/iio/iio_devbuf.rst`` for more information about how buffered +data is structured. + +4. IIO Interfacing Tools +======================== + +See ``Documentation/iio/iio_tools.rst`` for the description of the available IIO +interfacing tools. diff --git a/Documentation/iio/index.rst b/Documentation/iio/index.rst index dfcf9618568a..03829b2de2c0 100644 --- a/Documentation/iio/index.rst +++ b/Documentation/iio/index.rst @@ -24,6 +24,7 @@ Industrial I/O Kernel Drivers ad7944 adis16475 adis16480 + adis16550 adxl380 bno055 ep93xx_adc -- 2.34.1
