linux-stable.git/include/linux/iio/iio.h, branch linux-3.13.y

iio: Extend the event config interface

2013-10-12T11:32:19+00:00

The event configuration interface of the IIO framework has not been getting the
same attention as other parts. As a result it has not seen the same improvements
as e.g. the channel interface has seen with the introduction of the channel spec
struct. Currently all the event config callbacks take a u64 (the so called event
code) to pass all the different information about for which event the callback
is invoked. The callback function then has to extract the information it is
interested in using some macros with rather long names. Most information encoded
in the event code comes straight from the iio_chan_spec struct the event was
registered for. Since we always have a handle to the channel spec when we call
the event callbacks the first step is to add the channel spec as a parameter to
the event callbacks. The two remaining things encoded in the event code are the
type and direction of the event. Instead of passing them in one parameter, add
one parameter for each of them and remove the eventcode from the event
callbacks. The patch also adds a new iio_event_info parameter to the
{read,write}_event_value callbacks. This makes it possible, similar to the
iio_chan_info_enum for channels, to specify additional properties other than
just the value for an event. Furthermore the new interface will allow to
register shared events. This is e.g. useful if a device allows configuring a
threshold event, but the threshold setting is the same for all channels.

To implement this the patch adds a new iio_event_spec struct which is similar to
the iio_chan_spec struct. It as two field to specify the type and the direction
of the event. Furthermore it has a mask field for each one of the different
iio_shared_by types. These mask fields holds which kind of attributes should be
registered for the event. Creation of the attributes follows the same rules as
the for the channel attributes. E.g. for the separate_mask there will be a
attribute for each channel with this event, for the shared_by_type there will
only be one attribute per channel type. The iio_chan_spec struct gets two new
fields, 'event_spec' and 'num_event_specs', which is used to specify which the
events for this channel. These two fields are going to replace the channel's
event_mask field.

For now both the old and the new event config interface coexist, but over the
few patches all drivers will be converted from the old to the new interface.
Once that is done all code for supporting the old interface will be removed.

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

iio: add info_mask_[shared_by_dir/shared_by_all]

2013-09-15T16:45:49+00:00

These two additional info_mask bitmaps should allow all 'standard'
numeric attributes to be handled using the read_raw and write_raw
callbacks.  Whilst this should reduce code, the more important element
is that this makes these values easily accessible to in kernel users
of IIO devices.

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

iio: refactor info mask and ext_info attribute creation.

2013-09-15T16:43:20+00:00

Introduce an enum to specify whether the attribute is separate or
shared.

Factor out the bitmap handling for loop into a separate function.

Tidy up error handling and add a NULL assignment to squish a false
positive warning from GCC.

Change ext_info shared type from boolean to enum and update in all
drivers.

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

iio: drop info_mask from struct iio_dev

2013-09-15T16:41:21+00:00

Somehow this got missed when dropping all the code that used it
prior to the split.  Remove it now, there are no users.

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

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

iio: Remove trailing ; from function definitions

2013-08-31T18:09:38+00:00

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

iio: trigger: implement devm_iio_trigger_alloc/devm_iio_triger_free

2013-08-17T18:34:52+00:00

Add a resource managed devm_iio_trigger_alloc()/devm_iio_triger_free()
to automatically clean up triggers allocated by IIO drivers, thus
leading to simplified IIO drivers code.

Signed-off-by: Jacek Anaszewski 
Signed-off-by: Kyunmin Park 
Signed-off-by: Jonathan Cameron

iio: Fix documentation of devm_iio_device_free()

2013-08-03T21:21:53+00:00

Signed-off-by: Peter Meerwald 
Cc: Grygorii Strashko 
Cc: Oleksandr Kravchenko 
Signed-off-by: Jonathan Cameron

iio: core: implement devm_iio_device_alloc/devm_iio_device_free

2013-08-03T17:40:37+00:00

Add a resource managed devm_iio_device_alloc()/devm_iio_device_free()
to automatically clean up any allocations made by IIO drivers,
thus leading to simplified IIO drivers code.

In addition, this will allow IIO drivers to use other devm_*() API
(like devm_request_irq) and don't care about the race between
iio_device_free() and the release of resources by Device core
during driver removing.

Signed-off-by: Grygorii Strashko 
Signed-off-by: Oleksandr Kravchenko 
Tested-by: Oleksandr Kravchenko 
Reviewed-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron

iio: Fix iio_channel_has_info

2013-07-02T21:08:20+00:00

Since the info_mask split, iio_channel_has_info() is not working correctly.
info_mask_separate and info_mask_shared_by_type, it is not possible to compare
them directly with the iio_chan_info_enum enum. Correct that bit using the BIT()
macro.

Cc:  # 3.10.x
Signed-off-by: Alexandre Belloni 
Signed-off-by: Jonathan Cameron