What: /sys/bus/iio/devices/device[n] KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Hardware chip or device accessed by on communication port. Corresponds to a grouping of sensor channels. What: /sys/bus/iio/devices/trigger[n] KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: An event driven driver of data capture to an in kernel buffer. May be provided by a device driver that also has an IIO device based on hardware generated events (e.g. data ready) or provided by a separate driver for other hardware (e.g. periodic timer, gpio or high resolution timer). Contains trigger type specific elements. These do not generalize well and hence are not documented in this file. What: /sys/bus/iio/devices/device[n]:buffer KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Link to /sys/class/iio/device[n]/device[n]:buffer. n indicates the device with which this buffer buffer is associated. What: /sys/.../device[n]/name KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Description of the physical chip / device. Typically a part number. What: /sys/.../device[n]/sampling_frequency KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Some devices have internal clocks. This parameter sets the resulting sampling frequency. In many devices this parameter has an effect on input filters etc rather than simply controlling when the input is sampled. As this effects datardy triggers, hardware buffers and the sysfs direct access interfaces, it may be found in any of the relevant directories. If it effects all of the above then it is to be found in the base device directory as here. What: /sys/.../device[n]/sampling_frequency_available KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: When the internal sampling clock can only take a small discrete set of values, this file lists those availale. What: /sys/.../device[n]/in[_name][m]_raw KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Raw (unscaled no bias removal etc) voltage measurement from channel m. name is used in special cases where this does not correspond to externally available input (e.g. supply voltage monitoring in which case the file is in_supply_raw). What: /sys/.../device[n]/in[_name][m]_offset KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: If known for a device, offset to be added to in[m]_raw prior to scaling by in[_name][m]_scale in order to obtain voltage in millivolts. Not present if the offset is always 0 or unknown. If m is not present, then voltage offset applies to all in channels. May be writable if a variable offset is controlled by the device. Note that this is different to calibbias which is for devices that apply offsets to compensate for variation between different instances of the part, typically adjusted by using some hardware supported calibration procedure. What: /sys/.../device[n]/in[_name][m]_offset_available KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: If a small number of discrete offset values are available, this will be a space separated list. If these are independant (but options the same) for individual offsets then m should not be present. What: /sys/.../device[n]/in[_name][m]_offset_[min|max] KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: If a more or less continuous range of voltage offsets are supported then these specify the minimum and maximum. If shared by all in channels then m is not present. What: /sys/.../device[n]/in[_name][m]_calibbias KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Hardware applied calibration offset. (assumed to fix production inaccuracies) What /sys/.../device[n]/in[_name][m]_calibscale KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Hardware applied calibration scale factor. (assumed to fix production inaccuracies) What: /sys/.../device[n]/in[_name][m]_scale KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: If known for a device, scale to be applied to volt[m]_raw post addition of in[_name][m]_offset in order to obtain the measured voltage in millivolts. If shared across all in channels then m is not present. What: /sys/.../device[n]/in[m]-in[o]_raw KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Raw (unscaled) differential voltage measurement equivalent to channel m - channel o where these channel numbers apply to the physically equivalent inputs when non differential readings are separately available. In differential only parts, then all that is required is a consistent labelling. What: /sys/.../device[n]/accel[_x|_y|_z][m]_raw KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Acceleration in direction x, y or z (may be arbitrarily assigned but should match other such assignments on device) channel m (not present if only one accelerometer channel at this orientation). Has all of the equivalent parameters as per in[m]. Units after application of scale and offset are m/s^2. What: /sys/.../device[n]/gyro[_x|_y|_z][m]_raw KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Angular velocity about axis x, y or z (may be arbitrarily assigned) channel m (not present if only one gyroscope at this orientation). Data converted by application of offset then scale to radians per second. Has all the equivalent parameters as per in[m]. What: /sys/.../device[n]/incli[_x|_y|_z][m]_raw KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Inclination raw reading about axis x, y or z (may be arbitarily assigned) channel m (not present if only one inclinometer at this orientation). Data converted by application of offset and scale to Degrees. What: /sys/.../device[n]/magn[_x|_y|_z][m]_raw KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Magnetic field along axis x, y or z (may be arbitrarily assigned) channel m (not present if only one magnetometer at this orientation). Data converted by application of offset then scale to Gauss Has all the equivalent modifiers as per in[m]. What: /sys/.../device[n]/device[n]:event[m] KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Configuration of which hardware generated events are passed up to userspace. Some of these are a bit complex to generalize so this section is a work in progress. What: /sys/.../device[n]:event[m]/dev KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: major:minor character device numbers for the event line. Taking accel_x0 as an example What: /sys/.../device[n]:event[m]/accel_x0_thresh[_high|_low]_en KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Event generated when accel_x0 passes a threshold in correction direction (or stays beyond one). If direction isn't specified, either triggers it. Note driver will assume last p events requested are enabled where p is however many it supports. So if you want to be sure you have set what you think you have, check the contents of these. Drivers may have to buffer any parameters so that they are consistent when a given event type is enabled a future point (and not those for whatever alarm was previously enabled). What: /sys/.../device[n]:event[m]/accel_x0_roc[_high|_low]_en KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Same as above but based on the first differential of the value. What: /sys/.../device[n]:event[m]/accel_x0[_thresh|_roc][_high|_low]_period KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: A period of time (microsecs) for which the condition must be broken before an interrupt is triggered. Applies to all alarms if type is not specified. What: /sys/.../device[n]:event[m]/accel_x0[_thresh|_roc][_high|_low]_value KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: The actual value of the threshold in raw device units obtained by reverse application of scale and offfset to the acceleration in m/s^2. What: /sys/.../device[n]/scan_elements KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Directory containing interfaces for elements that will be captured for a single triggered sample set in the buffer. What: /sys/.../device[n]/scan_elements/[m]_accel_x0_en KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Scan element control for triggered data capture. m implies the ordering within the buffer. Next the type is specified with modifier and channel number as per the sysfs single channel access above. What: /sys/.../device[n]/scan_elements/accel[_x0]_precision KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Scan element precision within the buffer. Note that the data alignment must restrictions must be read from within buffer to work out full data alignment for data read via buffer_access chrdev. _x0 dropped if shared across all acceleration channels. What: /sys/.../device[n]/scan_elements/accel[_x0]_shift KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: A bit shift (to right) that must be applied prior to extracting the bits specified by accel[_x0]_precision. What: /sys/.../device[n]/device[n]:buffer:event/dev KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Buffer for device n event character device major:minor numbers. What: /sys/.../device[n]/device[n]:buffer:access/dev KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Buffer for device n access character device o major:minor numbers. What: /sys/.../device[n]:buffer/trigger KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: The name of the trigger source being used, as per string given in /sys/class/iio/trigger[n]/name. What: /sys/.../device[n]:buffer/length KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Number of scans contained by the buffer. What: /sys/.../device[n]:buffer/bps KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Bytes per scan. Due to alignment fun, the scan may be larger than implied directly by the scan_element parameters. What: /sys/.../device[n]:buffer/enable KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Actually start the buffer capture up. Will start trigger if first device and appropriate. What: /sys/.../device[n]:buffer/alignment KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org Description: Minimum data alignment. Scan elements larger than this are aligned to the nearest power of 2 times this. (may not be true in weird hardware buffers that pack data well)