| |
| 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) |
| |
