staging: iio: sysfs abi documentation. Add _type and _index attrs

Also remove no unused precision attr.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jonathan Cameron
2010-09-21 14:41:08 +01:00
committed by Greg Kroah-Hartman
parent 3215e31cc3
commit 10ba8ea9bd

View File

@@ -266,24 +266,41 @@ Description:
Directory containing interfaces for elements that will be captured Directory containing interfaces for elements that will be captured
for a single triggered sample set in the buffer. for a single triggered sample set in the buffer.
What: /sys/.../device[n]/buffer/scan_elements/[m]_accel_x0_en What: /sys/.../device[n]/buffer/scan_elements/accel_x0_en
KernelVersion: 2.6.37 KernelVersion: 2.6.37
Contact: linux-iio@vger.kernel.org Contact: linux-iio@vger.kernel.org
Description: Description:
Scan element control for triggered data capture. m implies the Scan element control for triggered data capture.
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]/buffer/scan_elements/accel[_x0]_precision What: /sys/.../device[n]/buffer/scan_elements/accel[_x0]_type
KernelVersion: 2.6.37 KernelVersion: 2.6.37
Contact: linux-iio@vger.kernel.org Contact: linux-iio@vger.kernel.org
Description: Description:
Scan element precision within the buffer. Note that the Description of the scan element data storage within the buffer
data alignment must restrictions must be read from within and hence the form in which it is read from userspace.
buffer to work out full data alignment for data read Form is [s|u]bits/storagebits. s or u specifies if signed
via buffer_access chrdev. _x0 dropped if shared across all (2's complement) or unsigned. bits is the number of bits of
acceleration channels. data and storagebits is the space (after padding) that it
occupies in the buffer. Note that some devices will have
additional information in the unused bits so to get a clean
value, the bits value must be used to mask the buffer output
value appropriately. The storagebits value also specifies the
data alignment. So s48/64 will be a signed 48 bit integer
stored in a 64 bit location aligned to a a64 bit boundary.
For other storage combinations this attribute will be extended
appropriately.
What: /sys/.../device[n]/buffer/scan_elements/accel[_x0]_index
KernelVersion: 2.6.37
Contact: linux-iio@vger.kernel.org
Description:
A single positive integer specifying the position of this
scan element in the buffer. Note these are not dependant on
what is enabled and may not be contiguous. Thus for userspace
to establish the full layout these must be used in conjunction
with all _en attributes to establish which channels are present,
and the relevant _type attributes to establish the data storage
format.
What: /sys/.../device[n]/buffer/scan_elements/accel[_x0]_shift What: /sys/.../device[n]/buffer/scan_elements/accel[_x0]_shift
KernelVersion: 2.6.37 KernelVersion: 2.6.37
@@ -291,4 +308,3 @@ Contact: linux-iio@vger.kernel.org
Description: Description:
A bit shift (to right) that must be applied prior to A bit shift (to right) that must be applied prior to
extracting the bits specified by accel[_x0]_precision. extracting the bits specified by accel[_x0]_precision.