iio: add the IIO backend framework

This is a Framework to handle complex IIO aggregate devices.

The typical architecture is to have one device as the frontend device which
can be "linked" against one or multiple backend devices. All the IIO and
userspace interface is expected to be registers/managed by the frontend
device which will callback into the backends when needed (to get/set
some configuration that it does not directly control).

The basic framework interface is pretty simple:
- Backends should register themselves with @devm_iio_backend_register()
- Frontend devices should get backends with @devm_iio_backend_get()

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240210-iio-backend-v11-5-f5242a5fb42a@analog.com
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: light: Add gain-time-scale helpers

Some light sensors can adjust both the HW-gain and integration time.
There are cases where adjusting the integration time has similar impact
to the scale of the reported values as gain setting has.

IIO users do typically expect to handle scale by a single writable 'scale'
entry. Driver should then adjust the gain/time accordingly.

It however is difficult for a driver to know whether it should change
gain or integration time to meet the requested scale. Usually it is
preferred to have longer integration time which usually improves
accuracy, but there may be use-cases where long measurement times can be
an issue. Thus it can be preferable to allow also changing the
integration time - but mitigate the scale impact by also changing the gain
underneath. Eg, if integration time change doubles the measured values,
the driver can reduce the HW-gain to half.

The theory of the computations of gain-time-scale is simple. However,
some people (undersigned) got that implemented wrong for more than once.

Add some gain-time-scale helpers in order to not dublicate errors in all
drivers needing these computations.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://lore.kernel.org/r/268d418e7cffcdaa2ece6738478bbc57692c213e.1680263956.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: add filter subfolder

Add filter subfolder for IIO devices that handle filter functionality.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: add addac subdirectory

For IIO devices that expose both ADC and DAC functionality.

Signed-off-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Link: https://lore.kernel.org/r/20211205114045.173612-2-cosmin.tanislav@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:cdc:ad7150: Move driver out of staging.

This capacitance to digital converter (CDC) driver is compliant with
the IIO ABI. Note, not all features supported (e.g. window event modes)
but the driver should be in a useful functional state.

The cleanup was done against QEMU emulation of the device rather than
actual hardware. Whilst this was a bit of an experiment, it made it
easy to confirm that the driver remained in a consistent working state
through the various refactors. If it worked in the first place, it
should still be working after this cleanup.

Given some IIO drivers require expensive hardware setups, (not particularly
true with this one) the use of QEMU may provide a viable way forward
for providing testing during code changes where previously we'd had
to rely on sharp eyes and crossed fingers.

Note, no explicit MAINTAINERS entry as it will be covered by the
generic catch-alls for ADI and IIO drivers which are sufficient.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210314181511.531414-25-jic23@kernel.org

iio: Add basic unit test for iio_format_value()

The IIO core provides a function to do formatting of fixedpoint numbers.

In the past there have been some issues with the implementation of the
function where for example negative numbers were not handled correctly.

Introduce a basic unit test based on kunit that tests the function and
ensures that the generated output matches the expected output.

This gives us some confidence that future modifications to the function
implementation will not break ABI compatibility.

To run the unit tests follow the kunit documentation and add

CONFIG_IIO=y
CONFIG_IIO_TEST_FORMAT=y

to the .kunitconfig and run

> ./tools/testing/kunit/kunit.py run
Configuring KUnit Kernel ...
Building KUnit Kernel ...
Starting KUnit Kernel ...
============================================================
======== [PASSED] iio-format ========
[PASSED] iio_test_iio_format_value_integer
[PASSED] iio_test_iio_format_value_fixedpoint
[PASSED] iio_test_iio_format_value_fractional
[PASSED] iio_test_iio_format_value_fractional_log2
[PASSED] iio_test_iio_format_value_multiple
============================================================
Testing complete. 21 tests run. 0 failed. 0 crashed.
Elapsed time: 8.242s total, 0.001s configuring, 3.865s building, 0.000s running

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20201215191743.2725-3-lars@metafoo.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: Kconfig: Provide title for IIO_TRIGGERED_EVENT symbol

For some embedded systems, a workflow involving external kernel modules
that implement IIO devices is more practical than working with in-tree
sources.

Kconfig symbols without any titles do not show up in menuconfig, and as
such are more difficult to configure granularly, as they need to be
selected by potentially unused/un-needed drivers.

Albeit, the IIO_TRIGGERED_EVENT is used by a single mainline driver, this
could allow for some out-of-tree drivers to use this kmod.

This change adds a title to the IIO_TRIGGERED_EVENT Kconfig symbol.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200924111758.196367-3-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: position: Add support for Azoteq IQS624/625 angle sensors

This patch adds support for the Azoteq IQS624 and IQS625 angular position
sensors, capable of reporting the angle of a rotating shaft down to 1 and
10 degrees of accuracy, respectively.

This patch also introduces a home for linear and angular position sensors.
Unlike resolvers, they are typically contactless and use the Hall effect.

Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

docs: iio: convert to ReST

Rename the iio documentation files to ReST, add an
index for them and adjust in order to produce a nice html
output via the Sphinx build system.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

counter: stm32-lptimer: add counter device

Add support for new counter device to stm32-lptimer.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Make anon_inodes unconditional

Make the anon_inodes facility unconditional so that it can be used by core
VFS code and pidfd code.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[christian@brauner.io: adapt commit message to mention pidfds]
Signed-off-by: Christian Brauner <christian@brauner.io>

drivers: iio: Kconfig: pedantic cleanup

Formatting of Kconfig files doesn't look so pretty, so just
take damp cloth and clean it up.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Make anon_inodes unconditional

Make the anon_inodes facility unconditional so that it can be used by core
VFS code.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

staging: iio: ad2s1200: Move driver out of staging

Move the iio driver for the ad2s1200 and ad2s1205 resolver-to-digital
converter out of staging, into mainline iio subsystems.

Signed-off-by: David Veenstra <davidjulianveenstra@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: afe: rescale: new driver

If an ADC channel measures the midpoint of a voltage divider, the
interesting voltage is often the voltage over the full resistance.
E.g. if the full voltage is too big for the ADC to handle.
Likewise, if an ADC channel measures the voltage across a shunt
resistor, with or without amplification, the interesting value is
often the current through the resistor.

This driver solves these problems by allowing to linearly scale a channel
and/or by allowing changes to the type of the channel.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: multiplexer: new iio category and iio-mux driver

When a multiplexer changes how an iio device behaves (for example
by feeding different signals to an ADC), this driver can be used
to create one virtual iio channel for each multiplexer state.

Depends on the generic multiplexer subsystem.

Cache any ext_info values from the parent iio channel, creating a private
copy of the ext_info attributes for each multiplexer state/channel.

Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: 104-quad-8: Add IIO support for the ACCES 104-QUAD-8

The ACCES 104-QUAD-8 is a general purpose quadrature encoder
counter/interface board. The 104-QUAD-8 is capable of monitoring the
outputs of eight encoders via four on-board LSI/CSI LS7266R1 24-bit
dual-axis quadrature counter chips. Core functions handled by the
LS7266R1, such as direction and total count, are available.

Performing a write to a counter's IIO_CHAN_INFO_RAW sets the counter and
also clears the counter's respective error flag. Although the counters
have a 25-bit range, only the lower 24 bits may be set, either directly
or via a counter's preset attribute. Interrupts are not supported by
this driver.

This driver adds IIO support for the ACCES 104-QUAD-8 and ACCES
104-QUAD-4. The base port addresses for the devices may be configured
via the base array module parameter.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: potentiostat: add LMP91000 support

Add support for the LMP91000 potentiostat which is used for chemical
sensing applications.

Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Add support for creating IIO devices via configfs

This is similar with support for creating triggers via configfs.
Devices will be hosted under:
* /config/iio/devices

We allow users to register "device types" under:
* /config/iio/devices/<device_types>/

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: light: add MAX30100 oximeter driver support

MAX30100 is an heart rate and pulse oximeter sensor that works using
two LEDS of different wavelengths, and detecting the light reflected
back.

This patchset adds support for both IR and RED LED channels which can
be processed in userspace to determine heart rate and blood oxygen
levels.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

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>

iio: core: Introduce IIO configfs support

This patch creates the IIO configfs root group. The group
will appear under <mount-point>/iio/, usually /config/iio.

We introduce configfs support in IIO in order to be able to easily
create IIO objects from userspace. The first supported IIO objects
are triggers introduced with next patches.

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Tested-by: Matt Ranostay <matt.ranostay@intel>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Move IIO Dummy Driver out of staging

This patch moves the reference IIO dummy driver from drivers/staging/iio
into a separate folder, drivers/iio/dummy and adds the proper Kconfig
and Makefile for it.

A new config menu entry called IIO dummy driver has also been added
in the Industrial I/O support menu, corresponding to this driver.

Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: mcp4531: Driver for Microchip digital potentiometers

Add support for Microchip digital potentiometers and rheostats
MCP4531, MCP4532, MCP4551, MCP4552
MCP4631, MCP4632, MCP4651, MCP4652

DEVICE Wipers Steps Resistor Opts (kOhm) i2c address
MCP4531 1 129 5, 10, 50, 100 010111x
MCP4532 1 129 5, 10, 50, 100 01011xx
MCP4551 1 257 5, 10, 50, 100 010111x
MCP4552 1 257 5, 10, 50, 100 01011xx
MCP4631 2 129 5, 10, 50, 100 0101xxx
MCP4632 2 129 5, 10, 50, 100 01011xx
MCP4651 2 257 5, 10, 50, 100 0101xxx
MCP4652 2 257 5, 10, 50, 100 01011xx

Datasheet: http://www.microchip.com/downloads/en/DeviceDoc/22096b.pdf

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: chemical: add SGX VZ89x VOC sensor support

Add support for VZ89X sensors VOC and CO2 reporting channels in
percentage which can be converted to part per million.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

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>

iio: Move generic buffer implementations to sub-directory

For generic IIO trigger implementations we already have a sub-directory,
but the generic buffer implementations currently reside in the IIO
top-level directory. The main reason is that things have historically grown
into this form.

With more generic buffer implementations on its way now is the perfect time
to clean this up and introduce a sub-directory for generic buffer
implementations to avoid too much clutter in the top-level directory.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Move callback buffer to its own module

Currently the IIO callback buffer implementation is directly built into the
IIO core module when enabled. Given that the callback buffer module is
standalone functionallity there is really no reason to do this. So move it
to its own module.

Also rename the source to follow the standard IIO module naming convention
as well as add a license notice to the file.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Deselect IIO_TRIGGER for IIO_KFIFO_BUF

iio kfifo can be used without trigger support so there is no need to build it.

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>

kconfig: use bool instead of boolean for type definition attributes

Support for keyword 'boolean' will be dropped later on.

No functional change.

Reference: http://lkml.kernel.org/r/cover.1418003065.git.cj@linux.com
Signed-off-by: Christoph Jaeger <cj@linux.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

iio: always select ANON_INODES

Without ANON_INODES, we get this build error:

drivers/built-in.o: In function `iio_event_getfd':
:(.text+0x14bf18): undefined reference to `anon_inode_getfd'

All other users explicitly select this symbol, so we should
do the same thing here.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Add AS3935 lightning sensor support

AS3935 chipset can detect lightning strikes and reports those back as
events and the estimated distance to the storm.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: hid-sensors: Added Inclinometer 3D

Added usage id processing for Inclinometer 3D. This uses IIO
interfaces for triggered buffer to present data to user
mode.This uses HID sensor framework for registering callback
events from the sensor hub.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Add new driver dht11

This driver handles DHT11 and DHT22 sensors.

Signed-off-by: Harald Geyer <harald@ccbib.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Remove GENERIC_HARDIRQ config option

After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

iio: Add tmp006 IR temperature sensor

the TI TMP006 is a non-contact temperature sensor with I2C interface;
it measures the surface temperature of a distance object using a
thermopile to absorb IR energy emitted from the object

the sensor has two channels: IR sensor voltage (16-bit) and reference
temperature of the chip (14-bit); datasheet is here:
http://www.ti.com/lit/ds/symlink/tmp006.pdf

v2 (thanks to Grygorii Strashko, Lars-Peter Clausen, Jonathan Cameron
for review comments):
* power down device on driver remove
* use sign_extend32()
* style cleanup
* add comments what channel raw LSBs mean
* spelling of thermopile

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: LM Sensors <lm-sensors@lm-sensors.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Revert "iio: add configuration option for debug support"

This reverts commit 98a5e9e99d05e9b6a14778b85631b55e8e349990.

IIO, like the rest of the kernel, should rely on dynamic debugging, not
have a special config option for it. That way, no user has to rebuild
their kernel to have debug messages, which is a good thing, let's not
revert back to the bad old days of the 2000's.

Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: add configuration option for debug support

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: remove mention of ring buffer from CONFIG_IIO_KFIFO_BUF, CONFIG_IIO_TRIGGER description

ring buffers are only in staging, don't mention them here

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: fix Kconfig typos

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:pressure: Add STMicroelectronics pressures driver

This patch adds a generic pressure driver for STMicroelectronics
pressure sensors, currently it supports: LPS331AP.

Signed-off-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio:trigger:sysfs Move out of staging.

This simple driver is rather useful. No issues about its interface
have been raised for some time hence the proposal to move it out
of staging.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>

staging:iio: Move adis library out of staging

Now that the adis library no longer depends on the sw_ring buffer implementation
we can move it out of staging.

While we are at it also sort the entries in the iio Kconfig and Makefile to be
in alphabetical order.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

staging:iio: add a callback buffer for in kernel push interface

This callback buffer is meant to be opaque to users, but basically
adds a very simple pass through buffer to which data may be
pushed when it is inserted into the buffer list.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Remove duplicates for light/ in Kconfig and Makefile

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: hid-sensors: Added ALS

Added usage id processing for ALS. This uses IIO
interfaces for triggered buffer to present data to user
mode.This uses HID sensor framework for registering callback
events from the sensor hub.

Signed-off-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: hid-sensors: Added Compass/Magnetometer 3D

Added usage id processing for Compass 3D. This uses IIO
interfaces for triggered buffer to present data to user
mode.This uses HID sensor framework for registering callback
events from the sensor hub.

Signed-off-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: hid-sensors: Added Gyroscope 3D

Added usage id processing for Gyroscope 3D. This uses IIO
interfaces for triggered buffer to present data to user
mode.This uses HID sensor framework for registering callback
events from the sensor hub.

Signed-off-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: hid-sensors: Added accelerometer 3D

Added usage id processing for Accelerometer 3D.This uses IIO
interfaces for triggered buffer to present data to user
mode.This uses HID sensor framework for registering callback
events from the sensor hub.

Signed-off-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: hid-sensors: Common attribute and trigger

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: srinivas pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: fix spelling of subsystem

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Add helper function for initializing triggered buffers

Add a helper function for executing the common tasks which are usually involved
in setting up a simple software ringbuffer. It will allocate the buffer,
allocate the pollfunc and register the buffer.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: drop wrong reference from Kconfig

The documentation lives in drivers/staging/iio/Documentation, but
according to Jonathan it's obsolete and needs fixing.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging:iio: Move DAC drivers out of staging

The IIO DAC drivers are in a reasonably good shape. They all make use of channel
spec and non of them provides non-documented sysfs attributes. Code style should
be OK as well, both checkpatch and coccicheck only report trivial issues.

So lets move the whole folder out of staging.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: frequency: New driver for AD9523 SPI Low Jitter Clock Generator

Changes since V1:

Apply Jonathan's review feedback:
Revise device status attribute names, and split documentation into two sections.
Add additional comments, and fix indention issues.
Remove pointless zero initializations.
Revise return value handling.
Simplify some code sections.
Split store_eeprom and sync handling into separate functions.
Use strtobool where applicable.
Document platform data structures using kernel-doc style.

Use dev_to_iio_dev
write_raw IIO_CHAN_INFO_FREQUENCY: Reject values <= 0
Make patch target drivers/iio

Changes since V2:

Use for_each_clear_bit() and __set_bit() where applicable.
Add descriptive comment.
Avoid temporary for struct regulator.
spi_device_id name use ad9523-1, ad9523 will be added later.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: add LM3533 ambient-light-sensor driver

Add sub-driver for the ambient-light-sensor interface on National
Semiconductor / TI LM3533 lighting power chips.

The sensor interface can be used to control the LEDs and backlights of
the chip through defining five light zones and three sets of
corresponding output-current values.

The driver provides raw and mean adc readings along with the current
light zone through sysfs. A threshold event can be generated on zone
changes. The ALS-control output values can be set per zone for the three
current output channels.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: AT91: IIO: Add AT91 ADC driver.

Add the ADC driver for Atmel's AT91SAM9G20-EK, AT91SAM9M10G45-EK
and AT91SAM9X5 family boards.

It has support for both software and hardware triggers.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: amplifiers: New driver for AD8366 Dual-Digital Variable Gain Amplifier

Changes since V1:

Apply review feedback:
Introduce and use IIO_CHAN_INFO_HARDWAREGAIN
Introduce and use Use IIO_VAL_INT_PLUS_MICRO_DB

Modify out of staging include paths.
Convert to new iio core API naming.

Changes since V2:

more sanity checking in write_raw

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

IIO: Move the core files to drivers/iio

Take the core support + the kfifo buffer implentation out of
staging. Whilst we are far from done in improving this subsystem
it is now at a stage where the userspae interfaces (provided by
the core) can be considered stable.

Drivers will follow over a longer time scale.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>