linux-toradex.git/Documentation/ABI/testing/sysfs-bus-iio, branch v3.13

iio: Add a hysteresis event info attribute

2013-10-12T11:51:35+00:00

For some devices it is possible to configure a hysteresis for threshold (or
similar) events. This patch adds a new hysteresis event info type which allows
for easy creation and read/write handling of the sysfs attribute.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron

iio: Update unit of the voltage scale in the documentation

2013-10-01T15:19:14+00:00

The documentation says that the result of raw * scale should be in microvolts,
but in reallity all drivers actually report the scale so that the result is in
millivolts. So update the documentation to match reallity.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron

iio: Add INT_TIME (integration time) channel info attribute

2013-09-14T20:16:44+00:00

Integration time is in seconds; it controls the measurement
time and influences the gain of a sensor.

There are two typical ways that scaling is implemented in a device:
1) input amplifier,
2) reference to the ADC is changed.
These both result in the accuracy of the ADC varying (by applying its
sampling over a more relevant range).

Integration time is a way of dealing with noise inherent in the analog
sensor itself.  In the case of a light sensor, a mixture of photon noise
and device specific noise.  Photon noise is dealt with by either improving
the efficiency of the sensor, (more photons actually captured) which is not
easily varied dynamically, or by integrating the measurement over a longer
time period.  Note that this can also be thought of as an averaging of a
number of individual samples and is infact sometimes implemented this way.
Altering integration time implies that the duration of a measurement changes,
a fact the device's user may be interested in.

Hence it makes sense to distinguish between integration time and simple
scale. In some devices both types of control are present and whilst they
will have similar effects on the amplitude of the reading, their effect
on the noise of the measurements will differ considerably.

Used by adjd_s311, tsl4531, tcs3472
The following drivers have similar controls (and could be adapted):
* tsl2563 (integration time is controlled via CALIBSCALE among other things)
* tsl2583 (has integration_time device_attr, but driver doesn't use channels yet)
* tsl2x7x (has integration_time attr)

Signed-off-by: Peter Meerwald 
Cc: Jon Brenner 
Signed-off-by: Jonathan Cameron

staging: iio: Documentation sysfs-bus-iio add power_mode

2013-08-28T19:10:30+00:00

Add description about in_accelX_power_mode and
in_accel_power_mode_available.

Signed-off-by: Oleksandr Kravchenko 
Signed-off-by: Jonathan Cameron

iio: move ABI specification for store_eeprom; is used by ad9523, mcp4725 and ds1077 devices

2013-08-03T17:40:31+00:00

Signed-off-by: Peter Meerwald 
Reviewed-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron

iio: add DAC 500kohm_to_gnd to possible powerdown_modes

2013-08-03T17:40:31+00:00

Signed-off-by: Peter Meerwald 
Signed-off-by: Jonathan Cameron

iio: ABI doc: update scan_elements sysfs paths

2013-06-11T20:09:37+00:00

update ABI documentation with current paths related to scan_elements folder

Paths changed long time ago in commit: 26d25ae3f0d8ffe350aacc75b71198d6b35bd1f4

Signed-off-by: Alexandre Relange 
Signed-off-by: Jonathan Cameron

iio: Add pressure channel type

2012-11-20T21:26:38+00:00

This patch adds support for a new IIO channel type for pressure measurements.
This can for example be used for barometric pressure sensors.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron

iio: kernel version typo in sysfs-bus-iio

2012-07-08T09:39:58+00:00

Signed-off-by: Peter Meerwald 
Signed-off-by: Jonathan Cameron

iio: sysfs-bus-iio typo

2012-06-15T21:39:18+00:00

Signed-off-by: Peter Meerwald 
Acked-by: Jonathan Cameron 
Signed-off-by: Greg Kroah-Hartman