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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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.
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>
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>
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>
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>
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>
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>
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>
