Commit Graph

178 Commits

Author SHA1 Message Date
Andrew F. Davis 7d2c2acac5 iio: Make IIO value formating function globally available.
Make IIO value formating function globally available to allow IIO drivers
to output values as the core does.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-12-22 17:04:56 +00:00
Jonathan Cameron 8d6c16dd72 iio:configfs: Introduce iio/configfs.h to provide a location for the configfs_subsystem
This exported element needs to be accesible to all drivers using configfs
within IIO.  Previously it was in the sw_trig.h file which only convered one
such usecase.  This also fixes a sparse warning as it is now in a header
that makes sense to include from industrialio-configfs.c

Signed-off-by: Jonathan Cameron < jic23@kernel.org>
2015-12-05 16:25:30 +00:00
Daniel Baluta b662f809d4 iio: core: Introduce IIO software triggers
A software trigger associates an IIO device trigger with a software
interrupt source (e.g: timer, sysfs). This patch adds the generic
infrastructure for handling software triggers.

Software interrupts sources are kept in a iio_trigger_types_list and
registered separately when the associated kernel module is loaded.

Software triggers can be created directly from drivers or from user
space via configfs interface.

To sum up, this dynamically creates "triggers" group to be found under
/config/iio/triggers and offers the possibility of dynamically
creating trigger types groups. The first supported trigger type is
"hrtimer" found under /config/iio/triggers/hrtimer.

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-12-03 18:19:27 +00:00
Lars-Peter Clausen 2d6ca60f32 iio: Add a DMAengine framework based buffer
Add a generic fully device independent DMA buffer implementation that uses
the DMAegnine framework to perform the DMA transfers. This can be used by
converter drivers that whish to provide a DMA buffer for converters that
are connected to a DMA core that implements the DMAengine API.

Apart from allocating the buffer using iio_dmaengine_buffer_alloc() and
freeing it using iio_dmaengine_buffer_free() no additional converter driver
specific code is required when using this DMA buffer implementation.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-10-25 13:55:32 +00:00
Lars-Peter Clausen 670b19ae9b iio: Add generic DMA buffer infrastructure
The traditional approach used in IIO to implement buffered capture requires
the generation of at least one interrupt per sample. In the interrupt
handler the driver reads the sample from the device and copies it to a
software buffer. This approach has a rather large per sample overhead
associated with it. And while it works fine for samplerates in the range of
up to 1000 samples per second it starts to consume a rather large share of
the available CPU processing time once we go beyond that, this is
especially true on an embedded system with limited processing power. The
regular interrupt also causes increased power consumption by not allowing
the hardware into deeper sleep states, which is something that becomes more
and more important on mobile battery powered devices.

And while the recently added watermark support mitigates some of the issues
by allowing the device to generate interrupts at a rate lower than the data
output rate, this still requires a storage buffer inside the device and
even if it exists it is only a few 100 samples deep at most.

DMA support on the other hand allows to capture multiple millions or even
more samples without any CPU interaction. This allows the CPU to either go
to sleep for longer periods or focus on other tasks which increases overall
system performance and power consumption. In addition to that some devices
might not even offer a way to read the data other than using DMA, which
makes DMA mandatory to use for them.

The tasks involved in implementing a DMA buffer can be divided into two
categories. The first category is memory buffer management (allocation,
mapping, etc.) and hooking this up the IIO buffer callbacks like read(),
enable(), disable(), etc. The second category of tasks is to setup the
DMA hardware and manage the DMA transfers. Tasks from the first category
will be very similar for all IIO drivers supporting DMA buffers, while the
tasks from the second category will be hardware specific.

This patch implements a generic infrastructure that take care of the former
tasks. It provides a set of functions that implement the standard IIO
buffer iio_buffer_access_funcs callbacks. These can either be used as is or
be overloaded and augmented with driver specific code where necessary.

For the DMA buffer support infrastructure that is introduced in this series
sample data is grouped by so called blocks. A block is the basic unit at
which data is exchanged between the application and the hardware. The
application is responsible for allocating the memory associated with the
block and then passes the block to the hardware. When the hardware has
captured the amount of samples equal to size of a block it will notify the
application, which can then read the data from the block and process it.
The block size can freely chosen (within the constraints of the hardware).
This allows to make a trade-off between latency and management overhead.
The larger the block size the lower the per sample overhead but the latency
between when the data was captured and when the application will be able to
access it increases, in a similar way smaller block sizes have a larger per
sample management overhead but a lower latency. The ideal block size thus
depends on system and application requirements.

For the time being the infrastructure only implements a simple double
buffered scheme which allocates two blocks each with half the size of the
configured buffer size. This provides basic support for capturing
continuous uninterrupted data over the existing file-IO ABI. Future
extensions to the DMA buffer infrastructure will give applications a more
fine grained control over how many blocks are allocated and the size of
each block. But this requires userspace ABI additions which are
intentionally not part of this patch and will be added separately.

Tasks of the second category need to be implemented by a device specific
driver. They can be hooked up into the generic infrastructure using two
simple callbacks, submit() and abort().

The submit() callback is used to schedule DMA transfers for blocks. Once a
DMA transfer has been completed it is expected that the buffer driver calls
iio_dma_buffer_block_done() to notify. The abort() callback is used for
stopping all pending and active DMA transfers when the buffer is disabled.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-10-25 13:54:34 +00:00
Lars-Peter Clausen e18a2ad45c iio: Add buffer enable/disable callbacks
This patch adds a enable and disable callback that is called when the
buffer is enabled/disabled. This can be used by buffer implementations that
need to do some setup or teardown work. E.g. a DMA based buffer can use
this to start/stop the DMA transfer.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-10-25 13:52:31 +00:00
Lars-Peter Clausen b440655b89 iio: Add support for indicating fixed watermarks
For buffers which have a fixed wake-up watermark the watermark attribute
should be read-only. Add a new FIXED_WATERMARK flag to the
struct iio_buffer_access_funcs, which can be set by a buffer
implementation.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-10-25 13:51:11 +00:00
Vladimir Barinov 735ad074ff iio: Support triggered events
Support triggered events.

This is useful for chips that don't have their own interrupt sources.
It allows to use generic/standalone iio triggers for those drivers.

Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-27 20:47:09 +01:00
Linus Walleij a0175b9c76 iio: st_sensors: add debugfs register read hook
This adds a debugfs hook to read/write registers in the ST
sensors using debugfs. Proved to be awesome help when trying
to debug why IRQs do not arrive.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-16 10:51:25 +01:00
Lars-Peter Clausen c689a923c8 iio: Add inverse unit conversion macros
Add inverse unit conversion macro to convert from standard IIO units to
units that might be used by some devices.

Those are useful in combination with scale factors that are specified as
IIO_VAL_FRACTIONAL. Typically the denominator for those specifications will
contain the maximum raw value the sensor will generate and the numerator
the value it maps to in a specific unit. Sometimes datasheets specify those
in different units than the standard IIO units (e.g. degree/s instead of
rad/s) and so we need to do a unit conversion.

From a mathematical point of view it does not make a difference whether we
apply the unit conversion to the numerator or the inverse unit conversion
to the denominator since (x / y) / z = x / (y * z). But as the denominator
is typically a larger value and we are rounding both the numerator and
denominator to integer values using the later method gives us a better
precision (E.g. the relative error is smaller if we round 8000.3 to 8000
rather than rounding 8.3 to 8).

This is where in inverse unit conversion macros will be used.

Marked for stable as used by some upcoming fixes.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-08 12:50:40 +01:00
Pengyu Ma ad30bad3a5 iio: declare struct to fix warning
When compile iio related driver the following warning shown:

include/linux/iio/trigger.h:35:34: warning: 'struct iio_trigger'
declared inside parameter list
  int (*set_trigger_state)(struct iio_trigger *trig, bool state);

include/linux/iio/trigger.h:38:18: warning: 'struct iio_dev'
declared inside parameter list
           struct iio_dev *indio_dev);

'struct iio_dev' and 'struct iio_trigger' was used before declaration,
forward declaration for these structs to fix warning.

Signed-off-by: Pengyu Ma <pengyu.ma@windriver.com>
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-08 12:28:46 +01:00
Cristina Opriceana 2854c098e2 include: linux: iio: Add missing kernel doc field
Fix kernel doc for the iio_dev_attr structure by adding its missing field.

Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-02 18:36:05 +01:00
Cristina Opriceana e52e95199d include: linux: iio: Fix function parameter name in kernel doc
Fix buffer name from kernel doc according to the function parameter.

Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-08-02 18:34:18 +01:00
Giuseppe Barba bc27381edb iio: st-sensors: add configuration for WhoAmI address
This patch permits to configure the WhoAmI register address
because some device could have not a standard address for
this register.

Signed-off-by: Giuseppe Barba <giuseppe.barba@st.com>
Reviewed-by: Denis Ciocca <denis.ciocca@st.com>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-07-23 20:43:04 +01:00
Cristina Opriceana fcc577dd55 iio: Fix parameters in iio_triggered_buffer_setup
This patch renames the top half handler and the bottom half handler
of iio_triggered_buffer_setup() in accordance with their usage.
The bottom half has been renamed to reflect the fact that it is a
thread based call, compliant with iio_alloc_pollfunc().
The names of the parameters were swapped, thus creating confusion.

Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-07-05 15:19:50 +01:00
Lars-Peter Clausen 225d59adf1 iio: Specify supported modes for buffers
For each buffer type specify the supported device modes for this buffer.
This allows us for devices which support multiple different operating modes
to pick the correct operating mode based on the modes supported by the
attached buffers.

It also prevents that buffers with conflicting modes are attached
to a device at the same time or that a buffer with a non-supported mode is
attached to a device (e.g. in-kernel callback buffer to a device only
supporting hardware mode).

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-06-01 11:31:12 +01:00
Martin Fuzzey 3f7f642b9b iio: core: add high pass filter attributes
Add a high pass filter attribute for measurements
(like the existing low pass)

Also add both high and low pass attributes for events.

Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-05-17 10:32:35 +01:00
Irina Tirdea faaa44955d iio: core: Introduce IIO_CHAN_INFO_OVERSAMPLING_RATIO
Some magnetometers can perform a number of repetitions in HW
for each measurement to increase accuracy. One example is
Bosch BMC150:
http://ae-bst.resource.bosch.com/media/products/dokumente/bmc150/BST-BMC150-DS000-04.pdf.

Introduce an interface to set the oversampling ratio
for these devices.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-05-10 20:31:44 +01:00
Vianney le Clément de Saint-Marcq c8a8585431 iio: core: Introduce IIO_CHAN_INFO_CALIBEMISSIVITY
Contact-less IR temperature sensors measure the temperature of an object
by using its thermal radiation.  Surfaces with different emissivity
ratios emit different amounts of energy at the same temperature.

IIO_CHAN_INFO_CALIBEMISSIVITY allows the user to inform the sensor of the
emissivity of the object in front of it, in order to effectively measure
its temperature.

A device providing such setting is Melexis's MLX90614:
http://melexis.com/Assets/IR-sensor-thermometer-MLX90614-Datasheet-5152.aspx.

Signed-off-by: Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>
Cc: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-04-09 15:03:05 +01:00
Octavian Purdila f4f4673b75 iio: add support for hardware fifo
Some devices have hardware buffers that can store a number of samples
for later consumption. Hardware usually provides interrupts to notify
the processor when the FIFO is full or when it has reached a certain
watermark level. This helps with reducing the number of interrupts to
the host processor and thus it helps decreasing the power consumption.

This patch enables usage of hardware FIFOs for IIO devices in
conjunction with software device buffers. When the hardware FIFO is
enabled the samples are stored in the hardware FIFO. The samples are
later flushed to the device software buffer when the number of entries
in the hardware FIFO reaches the hardware watermark or when a flush
operation is triggered by the user when doing a non-blocking read
on an empty software device buffer.

In order to implement hardware FIFO support the device drivers must
implement the following new operations: setting and getting the
hardware FIFO watermark level, flushing the hardware FIFO to the
software device buffer. The device must also expose information about
the hardware FIFO such it's minimum and maximum watermark and if
necessary a list of supported watermark values. Finally, the device
driver must activate the hardware FIFO when the device buffer is
enabled, if the current device settings allows it.

The software device buffer watermark is passed by the IIO core to the
device driver as a hint for the hardware FIFO watermark. The device
driver can adjust this value to allow for hardware limitations (such
as capping it to the maximum hardware watermark or adjust it to a
value that is supported by the hardware). It can also disable the
hardware watermark (and implicitly the hardware FIFO) it this value is
below the minimum hardware watermark.

Since a driver may support hardware FIFO only when not in triggered
buffer mode (due to different semantics of hardware FIFO sampling and
triggered sampling) this patch changes the IIO core code to allow
falling back to non-triggered buffered mode if no trigger is enabled.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-29 16:17:10 +01:00
Josselin Costanzi 37d3455672 iio: add watermark logic to iio read and poll
Currently the IIO buffer blocking read only wait until at least one
data element is available.
This patch makes the reader sleep until enough data is collected before
returning to userspace. This should limit the read() calls count when
trying to get data in batches.

Co-author: Yannick Bedhomme <yannick.bedhomme@mobile-devices.fr>
Signed-off-by: Josselin Costanzi <josselin.costanzi@mobile-devices.fr>
[rebased and remove buffer timeout]
Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-29 16:17:09 +01:00
Antonio Fiol a878a1a61a iio: max517: Add support for MAX520 and MAX521 chips.
MAX520 and MAX521 are protocol-compatible with the already supported
chips, just have more channels.

Signed-off-by: Antonio Fiol <antonio@fiol.es>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-03-28 10:57:34 +00:00
Daniel Baluta 293487c8ec iio: Export userspace IIO headers
After UAPI header file split [1] all user-kernel interfaces were
placed under include/uapi/.

This patch moves IIO user specific API from:
	* include/linux/iio/events.h => include/uapi/linux/iio/events.h
	* include/linux/types.h => include/uapi/linux/types.h

Now there is no need for nasty tricks to compile userspace programs
(e.g iio_event_monitor). Just installing the kernel headers with
make headers_install command does the job.

[1] http://lwn.net/Articles/507794/

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-02-14 17:05:03 +00:00
Irina Tirdea 2f0ecb7c65 iio: core: Introduce IIO_CHAN_INFO_DEBOUNCE_COUNT and _TIME
The pedometer needs to filter out false steps that might be generated by
tapping the foot, sitting, etc. To do that it computes the number of
steps that occur in a given time and decides the user is moving only
if this value is over a threshold. E.g.: the user starts moving only
if he takes 4 steps in 3 seconds. This filter is applied only when
the user starts moving.

A device that has such pedometer functionality is Freescale's MMA9553L:
http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf.

To export this feature, this patch introduces IIO_CHAN_INFO_DEBOUNCE_COUNT
and IIO_CHAN_INFO_DEBOUNCE_TIME. For the pedometer, in_steps_debounce_count
will specify the number of steps that need to occur in
in_steps_debounce_time seconds so that the pedometer decides the user is
moving.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-29 18:49:57 +00:00
Karol Wrona 50dd64d57e iio: common: ssp_sensors: Add sensorhub driver
Sensorhub  is MCU dedicated to collect data and manage several sensors.
Sensorhub is a spi device which provides a layer for IIO devices. It provides
some data parsing and common mechanism for sensorhub sensors.

Adds common sensorhub library for sensorhub driver and iio drivers
which uses sensorhub MCU to communicate with sensors.

Signed-off-by: Karol Wrona <k.wrona@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-29 18:49:05 +00:00
Irina Tirdea 17a2cbc279 iio: core: Remove IIO_EV_TYPE_INSTANCE
By introducing IIO_EV_TYPE_CHANGE, IIO_EV_TYPE_INSTANCE becomes redundant.
The effect of IIO_EV_TYPE_INSTANCE can be obtained by using IIO_EV_TYPE_CHANGE
with IIO_EV_INFO_VALUE set to 1.

Remove all instances of IIO_EV_TYPE_INSTANCE and replace them with
IIO_EV_TYPE_CHANGE where needed.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-27 18:49:55 +00:00
Irina Tirdea 27be84236d iio: core: Introduce CHANGE event type
A step detector will generate an interrupt each time N step are detected.
A device that has such pedometer functionality is Freescale's MMA9553L:
http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf.

Introduce IIO_EV_TYPE_CHANGE event type for events that are generated
when the channel passes a threshold on the absolute change in value.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-27 18:49:55 +00:00
Irina Tirdea d37f6836fa iio: core: Introduce IIO_CHAN_INFO_CALIBWEIGHT
Some devices need the weight of the user to compute other
parameters. One of this devices is Freescale's MMA9553L
(http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf)
that needs the weight of the user to compute the number of calories burnt.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-27 18:49:54 +00:00
Irina Tirdea 5a1a932981 iio: core: Introduce IIO_VELOCITY and IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z
Some devices export the current speed value of the user.

One of this devices is Freescale's MMA9553L
(http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf)
that computes the speed of the user based on the number of steps and
stride length.

Introduce a new channel type VELOCITY and a modifier for the magniture or
norm of the velocity vector, IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-27 18:49:54 +00:00
Irina Tirdea cc3c9eecae iio: core: Introduce DISTANCE channel type
Some devices export an estimation of the distance the user has covered
since the last reset.

One of this devices is Freescale's MMA9553L
(http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf)
that computes the distance based on the stride length and step rate.

Introduce a new channel type DISTANCE to export these values.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-27 18:49:53 +00:00
Irina Tirdea 72c6664467 iio: core: Introduce ENERGY channel type
Human activity sensors report the energy burnt by the user.
One of this devices is Freescale's MMA9553L
(http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf)
that computes the number of calories based on weight and step rate.

Introduce a new channel type ENERGY to export these values.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-27 18:49:52 +00:00
Karol Wrona 03af03ad7c iio: Add new operating mode for non triggered sw buffers
There was a need for non triggered software buffer type.  It can be used when
triggered model does not fit and INDIO_BUFFER_HARDWARE causes confusion because
the data stream can be obtained not directly form hardware backend.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Karol Wrona <k.wrona@samsung.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2015-01-25 22:53:38 +00:00
Greg Kroah-Hartman 6e49557b31 First round of IIO new drivers, cleanups and functionality for the 3.20 cycle take 2
Updated pull request with Daniel's fix on top for the power management
 Kconfig changes that had snuck in since last update of the IIO tree
 worked it's way through from mainline.
 
 Original pull message
 
 New device support
 * jsa1212 proxmity / ambient light sensor
 * SM08500 supported added to the kxcjk-1013 accelerometer driver
 * KMX61 Accelerometer/Magnetometer.  This took a somewhat rocky path
   being first merged, then reverted for a rewrite after a discussion of
   how to support additional functionality and finally being merged prior
   to some last reviews coming in, with resultant follow up patches.
 * Freescale mma9551l driver (minor follow up warning supression patch).
 * Semtech SX9500 proximity device driver.
 * ak8975 gains support for ak09911 and ak09912 and drop the standalone driver
   for the ak09911.
 
 New functionality
  * Dummy driver gains some virtual registers making it more flexible.
  * IIO_ACTIVITY channel types, with modifiers running, walking etc.  This is
    to support on chip motion clasifiers.  As such it is in the form of a
    confidence percentage.  The only devices so far only do binary decisions
    but this gives us room when other devices give more nuanced clasification.
  * IIO_EV_DIR_NONE type for events where there is no obvious direction.
    First case is step detection.
  * IIO_STEPS channel type for pedometers.
  * ENABLE mask element used to control turning on counting types such as
    the pedometer that need a 'start point'.
  * INSTANCE event type to support things that happen once.
  * info element for height calibration (used in various motion estimation
    algorithms). Note heigh tof use
  * dummy driver demonstration of the use of all the new bits above.
  * event monitor support for the new events.
  * inv_mpu6050 gains an i2c mux to allow bypassing the device to access
    additional devices connected on the other side of it.  Note that in
    Windows these are handled by firmware on the device and not exposed
    directly.
  * inv_mpu6050 gains ACPI enumeration.
  * inkern interface gains iio_write_channel_raw to allow in kernel users
    of DAC functionality via a simple wrapper.
  * Document input current readings in the ABI docs.
  * Add an error message when we get an out of range error in device tree
    processing for the in kernel interfaces.  Basically a device tree debugging
    aid.
  * Add a sanity check that a scan index for a channel is unique during
    registration.  There to help catch bugs as this should never happen
    in a bug free driver.
 
 Cleanups and fixlets
 
  A rework of buffer registration from Lars - a precursor to some other
  upcoming new stuff (a few patches from others rolled in here as well).
  * Ensure all drivers register the same channels for the device and buffer.
  * Move buffer registration into the core rather than using the old
    two step approach.  Now we have simple ways of using a unified set channels
    for both without requiring channels be exposed by both interface, this
    removes a fair bit of boilerplate.
  * Stop sca3000 and ad5933 (both in staging) enabling buffer channels by
    default. It has long be convention in IIO to startup with no channels
    enabled and leave it up to userspace to say what goes in the buffer.
    Getting rid of these allows us to drop export of iio_scan_mask_set.
  * Drop get_bytes_per_datum from iio_buffer_access_funcs as not been used
    for a while.
  * Allocate standard buffer attributes in the core rather than in every
    driver with a buffer.
  * Make the length attribute read only when a driver is not able to set
    the length.
  * Drop the get_length callback for buffers as it is already available in
    struct iio_buffer.
  * Drop an unused arguement form iio_kfifo_allocate and add devm allocator
    for it.
  * some kconfig entries gain anotation with the resulting module name.
  * Fix a resulting compile issue in dummy driver due to a stub taking
    wrong parameters as a result of the above rework.
  * Fix an off by 2 error in copying the core assigned buffer attributes.
 
 Other cleanups,
  * Trivial space before comma fixups.
  * ak8975 fixlets - none critical.  Rework to allow more device support.
  * Drop unnecessary sizeof(u8) calls.
  * bmp280 - refactor the compensation code to reduce copy operations and
    code length.  A second patch futher optimized this and performed some
    other minor cleanups.
  * kxcjk-1013 - various power control cleanups to avoid unnecessary enable
    / disable of device.  Make sure it is only controlled at all if CONFIG_PM
    is enabled.  Also som cleanups of error paths.
  * Small cleanups in adf4530 driver - pointless message and unnecessary braces.
  * Clarifiy the proximity ABI docs to make it clear it should get bigger
    as we move futher away.
  * Drop a misleading comment form industrialio-core.c
  * Trivial white space cleanups.
  * sca3000 looses an unused debug function.
  * Fix char unsigned ordering in ad8366
  * Increase the sleep time in ad9523 to make it predictable (value didn't
    really matter so make it more than 20 msecs)
  * mxs-lradc touchscreen property cleanups in device tree are fixed to ensure
    the meet all the 'interesting' documentation.
  * A couple of cleanups for the staging ad5933 driver to avoid unnecessary
    conversion to a processed temperature vlaue in kernel and remove
    platform data form the state structure as not needed after probe.
  * Fix a wrong scale factor in the docs.
 
 Misc
  * Add IIO include files to the maintainers entry.
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Merge tag 'iio-for-3.20a_take2' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-testing

Jonathan writes:

First round of IIO new drivers, cleanups and functionality for the 3.20 cycle take 2

Updated pull request with Daniel's fix on top for the power management
Kconfig changes that had snuck in since last update of the IIO tree
worked it's way through from mainline.

Original pull message

New device support
* jsa1212 proxmity / ambient light sensor
* SM08500 supported added to the kxcjk-1013 accelerometer driver
* KMX61 Accelerometer/Magnetometer.  This took a somewhat rocky path
  being first merged, then reverted for a rewrite after a discussion of
  how to support additional functionality and finally being merged prior
  to some last reviews coming in, with resultant follow up patches.
* Freescale mma9551l driver (minor follow up warning supression patch).
* Semtech SX9500 proximity device driver.
* ak8975 gains support for ak09911 and ak09912 and drop the standalone driver
  for the ak09911.

New functionality
 * Dummy driver gains some virtual registers making it more flexible.
 * IIO_ACTIVITY channel types, with modifiers running, walking etc.  This is
   to support on chip motion clasifiers.  As such it is in the form of a
   confidence percentage.  The only devices so far only do binary decisions
   but this gives us room when other devices give more nuanced clasification.
 * IIO_EV_DIR_NONE type for events where there is no obvious direction.
   First case is step detection.
 * IIO_STEPS channel type for pedometers.
 * ENABLE mask element used to control turning on counting types such as
   the pedometer that need a 'start point'.
 * INSTANCE event type to support things that happen once.
 * info element for height calibration (used in various motion estimation
   algorithms). Note heigh tof use
 * dummy driver demonstration of the use of all the new bits above.
 * event monitor support for the new events.
 * inv_mpu6050 gains an i2c mux to allow bypassing the device to access
   additional devices connected on the other side of it.  Note that in
   Windows these are handled by firmware on the device and not exposed
   directly.
 * inv_mpu6050 gains ACPI enumeration.
 * inkern interface gains iio_write_channel_raw to allow in kernel users
   of DAC functionality via a simple wrapper.
 * Document input current readings in the ABI docs.
 * Add an error message when we get an out of range error in device tree
   processing for the in kernel interfaces.  Basically a device tree debugging
   aid.
 * Add a sanity check that a scan index for a channel is unique during
   registration.  There to help catch bugs as this should never happen
   in a bug free driver.

Cleanups and fixlets

 A rework of buffer registration from Lars - a precursor to some other
 upcoming new stuff (a few patches from others rolled in here as well).
 * Ensure all drivers register the same channels for the device and buffer.
 * Move buffer registration into the core rather than using the old
   two step approach.  Now we have simple ways of using a unified set channels
   for both without requiring channels be exposed by both interface, this
   removes a fair bit of boilerplate.
 * Stop sca3000 and ad5933 (both in staging) enabling buffer channels by
   default. It has long be convention in IIO to startup with no channels
   enabled and leave it up to userspace to say what goes in the buffer.
   Getting rid of these allows us to drop export of iio_scan_mask_set.
 * Drop get_bytes_per_datum from iio_buffer_access_funcs as not been used
   for a while.
 * Allocate standard buffer attributes in the core rather than in every
   driver with a buffer.
 * Make the length attribute read only when a driver is not able to set
   the length.
 * Drop the get_length callback for buffers as it is already available in
   struct iio_buffer.
 * Drop an unused arguement form iio_kfifo_allocate and add devm allocator
   for it.
 * some kconfig entries gain anotation with the resulting module name.
 * Fix a resulting compile issue in dummy driver due to a stub taking
   wrong parameters as a result of the above rework.
 * Fix an off by 2 error in copying the core assigned buffer attributes.

Other cleanups,
 * Trivial space before comma fixups.
 * ak8975 fixlets - none critical.  Rework to allow more device support.
 * Drop unnecessary sizeof(u8) calls.
 * bmp280 - refactor the compensation code to reduce copy operations and
   code length.  A second patch futher optimized this and performed some
   other minor cleanups.
 * kxcjk-1013 - various power control cleanups to avoid unnecessary enable
   / disable of device.  Make sure it is only controlled at all if CONFIG_PM
   is enabled.  Also som cleanups of error paths.
 * Small cleanups in adf4530 driver - pointless message and unnecessary braces.
 * Clarifiy the proximity ABI docs to make it clear it should get bigger
   as we move futher away.
 * Drop a misleading comment form industrialio-core.c
 * Trivial white space cleanups.
 * sca3000 looses an unused debug function.
 * Fix char unsigned ordering in ad8366
 * Increase the sleep time in ad9523 to make it predictable (value didn't
   really matter so make it more than 20 msecs)
 * mxs-lradc touchscreen property cleanups in device tree are fixed to ensure
   the meet all the 'interesting' documentation.
 * A couple of cleanups for the staging ad5933 driver to avoid unnecessary
   conversion to a processed temperature vlaue in kernel and remove
   platform data form the state structure as not needed after probe.
 * Fix a wrong scale factor in the docs.

Misc
 * Add IIO include files to the maintainers entry.
2015-01-21 10:13:37 +08:00
Karol Wrona 780103fef5 iio: kfifo: Add resource management devm_iio_kfifo_allocate/free
iio kfifo allocate/free gained their devm_ wrappers.

Signed-off-by: Karol Wrona <k.wrona@samsung.com>
Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-26 11:39:57 +00:00
Karol Wrona 7ab374a053 iio: kfifo: Remove unused argument in iio_kfifo_allocate
indio_dev was unused in function body plus some small style fix - add new
lines after "if(sth) return sth" and before the last return statement.

The argument was removed also in its client.

Signed-off-by: Karol Wrona <k.wrona@samsung.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-26 11:20:38 +00:00
Ivan T. Ivanov 09546a3063 iio: consumer.h: Fix scale factor in function comment
1 milivolt is equal to 1000000 nanovolts.

Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:36 +00:00
Lars-Peter Clausen 374956600e iio: buffer: Drop get_length callback
We already do have the length field in the struct iio_buffer which is
expected to be in sync with the current size of the buffer. And currently
all implementations of the get_length callback either return this field or a
constant number.

This patch removes the get_length callback and replaces all occurrences in
the IIO core with directly accessing the length field of the buffer.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:34 +00:00
Lars-Peter Clausen 08e7e0adaa iio: buffer: Allocate standard attributes in the core
All buffers want at least the length and the enable attribute. Move the
creation of those attributes to the core instead of having to do this in
each individual buffer implementation. This allows us to get rid of some
boiler-plate code.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:33 +00:00
Lars-Peter Clausen 616dde2a1e iio: Remove get_bytes_per_datum() from iio_buffer_access_funcs
There haven't been any users of the get_bytes_per_datum() callback for a
while. The core assumes that the number of bytes per datum can be calculated
based on the enabled channels and the storage size of the channel and
iio_compute_scan_bytes() is used to compute this number. So remove the
callback.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:32 +00:00
Lars-Peter Clausen 3e1b6c95b9 iio: Move buffer registration to the core
Originally device and buffer registration were kept as separate operations
in IIO to allow to register two distinct sets of channels for buffered and
non-buffered operations. This has since already been further restricted and
the channel set registered for the buffer needs to be a subset of the
channel set registered for the device. Additionally the possibility to not
have a raw (or processed) attribute for a channel which was registered for
the device was added a while ago. This means it is possible to not register
any device level attributes for a channel even if it is registered for the
device. Also if a channel's scan_index is set to -1 and the channel is
registered for the buffer it is ignored.

So in summary it means it is possible to register the same channel array for
both the device and the buffer yet still end up with distinctive sets of
channels for both of them. This makes the argument for having to have to
manually register the channels for both the device and the buffer invalid.
Considering that the vast majority of all drivers want to register the same
set of channels for both the buffer and the device it makes sense to move
the buffer registration into the core to avoid some boiler-plate code in the
device driver setup path.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:31 +00:00
Lars-Peter Clausen 217a5cf0a1 iio: Unexport iio_scan_mask_set()
Individual drivers should not be messing with the scan mask that contains
the list of enabled channels. This is something that is supposed to be
managed by the core.

Now that the last few drivers that used it to configure a default scan mask
have been updated to not do this anymore we can unexport the function.

Note, this patch also requires moving a few functions around so they are all
declared before the first internal user.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:29 +00:00
Dmitry Eremin-Solenikov f9380e7123 iio: inkern: add iio_write_channel_raw
Introduce API for easy in-kernel setting of DAC values.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:27 +00:00
Greg Kroah-Hartman deef2a118a Merge 3.18-rc7 into staging-work.
We want those staging fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-02 16:20:59 -08:00
Irina Tirdea bcdf28fb1b iio: core: Introduce IIO_CHAN_INFO_CALIBHEIGHT
Some devices need the height of the user to compute various
parameters. One of this devices is Freescale's MMA9553L
(http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf)
that needs the height of the user to compute the stride length which
is used further to determine distance, speed and activity type.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-11-22 11:05:56 +00:00
Irina Tirdea a88bfe7858 iio: core: Introduce STEPS channel, ENABLE mask and INSTANCE event
These changes are needed to support the functionality of a pedometer.
A pedometer has two basic functionalities: step counter and step detector.

The step counter needs to be enabled and then it will count the steps
in its hardware register. Whenever the application needs to check
the step count, it will read the step counter register. To support the
step counter a new channel type STEPS is added. Since the pedometer needs
to be enabled first so that the hardware can count and store the steps,
we need a specific ENABLE channel info mask.

The step detector will generate an interrupt each time a step is detected.
To support this functionality we add a new event type INSTANCE.

For more information on the Android requirements for step counter and step
detector see:
http://source.android.com/devices/sensors/composite_sensors.html#counter
and http://source.android.com/devices/sensors/composite_sensors.html#detector.

A device that has the pedometer functionality this interface needs to
support is Freescale's MMA9553L:
http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-11-22 11:05:51 +00:00
Irina Tirdea 1843c2f3de iio: core: Introduce IIO_EV_DIR_NONE
For some events (e.g.: step detector) a direction does not make sense.

Add IIO_EV_DIR_NONE to be used with such events and generate sysfs event
attributes that do not contain direction.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-11-22 11:05:49 +00:00
Daniel Baluta 55aebeb926 iio: core: Introduce IIO_ACTIVITY channel
This channel will be used for exposing information about
activity composite sensors. Activities supported so far:
	* running
	* jogging
	* walking
	* still

THRESHOLD event is used to signal a change in the activity
state.

We associate a confidence interval for each activity expressed
as a percentage from 0 to 100.
  * 0, means the sensor IS NOT reporting that activity.
  * 100, means the sensor IS reporting that activity.

Users of this interface have two possible means to gather
information about the ongoing activities.

1. Event based, via event file descriptor
  * sensor may report an event when ENTERING an activity or LEAVING
    an activity based on a threshold value.
  * drivers will wake up applications waiting data on the event fd

2. Polling, by reading the sysfs associated attribute files:
  * /sys/bus/iio/devices/iio:device0/in_activity_running_input
expressed as percentage confidence value from 0 to 100.

This will offer an interface for Android significant motion
composite sensor defined here:
http://source.android.com/devices/sensors/composite_sensors.html

Activities listed above are supported by Freescale's MMA9553 sensor:
http://freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-11-22 11:05:47 +00:00
Cristina Ciocan ccf54555da iio: Fix IIO_EVENT_CODE_EXTRACT_DIR bit mask
The direction field is set on 7 bits, thus we need to AND it with 0111 111 mask
in order to retrieve it, that is 0x7F, not 0xCF as it is now.

Fixes: ade7ef7ba (staging:iio: Differential channel handling)
Signed-off-by: Cristina Ciocan <cristina.ciocan@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-11-15 16:04:56 +00:00
Greg Kroah-Hartman be61a0d784 First round of new drivers, features and cleanups for IIO in the 3.19 cycle.
New drivers / supported parts
 * rockchip - rk3066-tsadc variant
 * si7020 humidity and temperature sensor
 * mcp320x - add mcp3001, mcp3002, mcp3004, mcp3008, mcp3201, mcp3202
 * bmp280 pressure and temperature sensor
 * Qualcomm SPMI PMIC current ADC driver
 * Exynos_adc - support exynos7
 
 New features
 * vf610-adc - add temperature sensor support
 * Documentation of current attributes, scaled pressure, offset and
   scaled humidity, RGBC intensity gain factor and scale applied to
   differential voltage channels.
 * Bring iio_event_monitor up to date with newer modifiers.
 * Add of_xlate function to allow for complex channel mappings from the
   device tree.
 * Add -g parameter to generic_buffer example to allow for devices with
   directly fed (no trigger) buffers.
 * Move exynos driver over to syscon for PMU register access.
 
 Cleanups, fixes for new drivers
 * lis3l02dq drop an unneeded else.
 * st sensors - renam st_sensors to st_sensor_settings (for clarity)
 * st sensors - drop an unused parameter from all the probe utility
   functions.
 * vf610 better error handling and tidy up.
 * si7020 - cleanups following merge
 * as3935 - drop some unnecessary semicolons.
 * bmp280 - fix the pressure calculation.
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Merge tag 'iio-for-3.19a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First round of new drivers, features and cleanups for IIO in the 3.19 cycle.

New drivers / supported parts
* rockchip - rk3066-tsadc variant
* si7020 humidity and temperature sensor
* mcp320x - add mcp3001, mcp3002, mcp3004, mcp3008, mcp3201, mcp3202
* bmp280 pressure and temperature sensor
* Qualcomm SPMI PMIC current ADC driver
* Exynos_adc - support exynos7

New features
* vf610-adc - add temperature sensor support
* Documentation of current attributes, scaled pressure, offset and
  scaled humidity, RGBC intensity gain factor and scale applied to
  differential voltage channels.
* Bring iio_event_monitor up to date with newer modifiers.
* Add of_xlate function to allow for complex channel mappings from the
  device tree.
* Add -g parameter to generic_buffer example to allow for devices with
  directly fed (no trigger) buffers.
* Move exynos driver over to syscon for PMU register access.

Cleanups, fixes for new drivers
* lis3l02dq drop an unneeded else.
* st sensors - renam st_sensors to st_sensor_settings (for clarity)
* st sensors - drop an unused parameter from all the probe utility
  functions.
* vf610 better error handling and tidy up.
* si7020 - cleanups following merge
* as3935 - drop some unnecessary semicolons.
* bmp280 - fix the pressure calculation.
2014-11-05 11:42:48 -08:00
Ivan T. Ivanov acd8256723 iio: inkern: Add of_xlate function to struct iio_info
When #iio-cells is greater than '0', the driver could provide
a custom of_xlate function that reads the *args* and returns
the appropriate index in registered IIO channels array.

Add simple translation function, suitable for the most 1:1
mapped channels in IIO chips, and use it when driver did not
provide custom implementation.

Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-10-25 11:03:40 +01:00