When system bootup without get sensor property, set sensor
property will be fail.

If no get_feature operation done before set_feature, the sensor
properties will all be the initialized value, which is not the
same with sensor real properties. When set sensor property it will
write back to sensor the changed perperty data combines with other
sensor properties data, it is not right and may be dangerous.

In order to get all sensor properties, choose to read one of the sensor
properties(no matter read any sensor peroperty, driver will get all
the peroperties and return the requested one).

Fixes: 73c6768b ("iio: hid-sensors: Common attribute and trigger")
Signed-off-by: NSong Hongyan <hongyan.song@intel.com>
Acked-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Added timestamp channel. With this change, each sample has a timestamp.
This timestamp can be from the sensor hub when present or local kernel
timestamp. HID sensors can send timestamp with input data using usage id
HID_USAGE_SENSOR_TIME_TIMESTAMP. This timestamp value is converted to
nano seconds before pushing this sample to the iio core.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

While testing, it was observed that on some platforms the scale value
from iio sysfs for gyroscope is always 0 (E.g. Yoga 260). This results
in the final angular velocity component values to be zeros.

This is caused by insufficient precision of scale value displayed in sysfs.
If the precision is changed to nano from current micro, then this is
sufficient to display the scale value on this platform.
Since this can be a problem for all other HID sensors, increase scale
precision of all HID sensors to nano from current micro.

Results on Yoga 260:

name		scale before	scale now
--------------------------------------------
gyro_3d		0.000000	0.000000174
als			0.001000	0.001000000
magn_3d		0.000001	0.000001000
accel_3d		0.000009	0.000009806
Signed-off-by: NSong Hongyan <hongyan.song@intel.com>
Acked-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Neither sample frequency value nor hysteresis value can be set to be a
negative number, check and return "Invalid argument" if they are negative.

If not do this change, sample_frequency will be set into some unknown
value, read hysteresis value after write negative number will return
"Invalid argument".
Signed-off-by: NSong Hongyan <hongyan.song@intel.com>
Acked-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

According to IIO ABI definition, IIO_PRESSURE data output unit is
kilopascal:
http://lxr.free-electrons.com/source/Documentation/ABI/testing/sysfs-bus-iio

This patch fix output unit of HID pressure sensor IIO driver from pascal to
kilopascal to follow IIO ABI definition.
Signed-off-by: NKweh, Hock Leong <hock.leong.kweh@intel.com>
Reviewed-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Current API only allows setting one offset in the field. This API
is extended to set multiple offsets in the field report.
Also update parameters in the users of this API.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Some hid sensor feature report can contain more than one reports.
This API can now support receiving multiple values from the feature
report.
Also update the parameters in the users of this API.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This fixes the following sparse warning:

  CHECK   drivers/iio/common/hid-sensors/hid-sensor-attributes.c
drivers/iio/common/hid-sensors/hid-sensor-attributes.c:346:5: warning:
symbol 'hid_sensor_get_reporting_interval' was not declared. Should it be static?
Signed-off-by: NDaniel Baluta <daniel.baluta@intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Move the 'static' keyword to beginning of definition to silence the
following compilation warning:
drivers/iio/common/hid-sensors/hid-sensor-attributes.c:34:1: warning: ‘static’ is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: NSachin Kamat <sachin.kamat@samsung.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

For PROP_REPORT_INTERVAL, the spec does not mandate the presence
of the report interval unit in the feature report and expects the
default unit of measure to be used as milliseconds.

Currently, when the unit is not present, it gets set as zero leading
to issues in sampling frequency.

This patch sets the unit of measure to the default unit if it
is not defined by firmware.
Signed-off-by: NArchana Patni <archana.patni@intel.com>
Signed-off-by: NSubramony Sesha <subramony.sesha@intel.com>
Reviewed-by: NSrinivas Pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The "i < " was missing in this condition.

Fixes: 5d02edfc ('iio: hid-sensors: Convert units and exponent')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Added interface to get poll value in milli-seconds. This value is
changed by changing sampling frequency. This API allows clients
to wait for at least some poll milli seconds before reading a new sample.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

HID sensor hub specify a default unit and alternative units. This
along with unit exponent can be used adjust scale. This change
change HID sensor data units to IIO defined units for each
sensor type. So in this way user space can use a simply use:
"(data + offset) * scale" to get final result.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The structure with common attributes for hid-sensors isn't specific
to the iio-subsystem, so rename it to hid_sensor_common.
Signed-off-by: NAlexander Holler <holler@ahsoftware.de>
Acked-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The stuff in hid-sensor-attributes.h is needed by every piece which
uses hid-sensor-hub and merging it into hid-sensor-hub.h makes it accessible
from outside the iio subdirectory.
Signed-off-by: NAlexander Holler <holler@ahsoftware.de>
Acked-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

This patch contains the common code, which is used by all HID sensors.
There are some common set of attributes, which every hid sensor
needs it. This patch contains all such attributes processing.
Also the trigger interface is common among all HID sensors. This
patch contains common trigger functions utilized by all HID sensors.
Signed-off-by: Nsrinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>