History log of /linux-master/drivers/iio/magnetometer/st_magn_core.c
Revision Date Author Comments
# a9e19f63 15-Apr-2023 Marius Hoch <mail@mariushoch.de>

iio: magnetometer: st_accel: Add LSM303D

The lsm303d has the same register mapping as the lsm9ds0,
thus we can just re-use that.

Tested on a Lenovo Yoga Tablet 2 1051-F.

Signed-off-by: Marius Hoch <mail@mariushoch.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Hans de Goede <hansg@kernel.org>
Link: https://lore.kernel.org/r/20230415231130.115094-3-mail@mariushoch.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 721a2a7e 06-Jan-2023 Stephan Gerhold <stephan@gerhold.net>

iio: magnetometer: st_magn: Add LSM303C

The magnetometer part of ST LSM303C is similar (perhaps even identical)
to the already supported standalone LIS3MDL magnetometer, so just
add the new st,lsm303c-magn compatible for the existing definitions.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230106102239.9647-4-stephan@gerhold.net
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 12345968 07-Feb-2022 Miquel Raynal <miquel.raynal@bootlin.com>

iio: st_sensors: Stop abusing mlock to ensure internal coherency

An odr_lock has been introduced to protect local accesses to the odr
internal cache and ensure the cached value always reflected the actual
value. Using the mlock() for this purpose is no longer needed, so let's
drop these extra mutex_lock/unlock() calls.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220207143840.707510-8-miquel.raynal@bootlin.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 69c98879 07-Feb-2022 Miquel Raynal <miquel.raynal@bootlin.com>

iio: st_sensors: Return as early as possible from the _write_raw() callbacks

As there is no cleanup to do, let's return as early as possible in the
various ST sensor drivers _write_raw() callback functions.

There is no functional change.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20220207143840.707510-5-miquel.raynal@bootlin.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 0805b512 16-Jan-2022 Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio:st-sensors: Move exports into IIO_ST_SENSORS namespace

To avoid unnecessary pollution of the global symbol namespace move the
driver core and type specific core exports into their a new namespace
and import that where needed.

For more info see https://lwn.net/Articles/760045/

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Denis Ciocca <denis.ciocca@st.com>
Link: https://lore.kernel.org/r/20220116180535.2367780-14-jic23@kernel.org


# e4269651 23-Aug-2021 Alexandru Ardelean <aardelean@deviqon.com>

iio: st_sensors: remove reference to parent device object on st_sensor_data

The idea behind it, is that all devm_ calls in ST sensors are bound to the
parent device object.

However, the reference to that object is kept on both the st_sensor_data
struct and the IIO object parent (indio_dev->dev.parent).

This change only adds a bit consistency and uses the reference stored on
indio_dev->dev.parent, to enforce the assumption that all ST sensors' devm_
calls are bound to the same reference as the one store on st_sensor_data.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210823112204.243255-6-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 6b658c31 23-Aug-2021 Alexandru Ardelean <aardelean@deviqon.com>

iio: st_sensors: remove all driver remove functions

At this point all ST driver remove functions do iio_device_unregister().
This change removes them from them and replaces all iio_device_register()
with devm_iio_device_register().

This can be done in a single change relatively easy, since all these remove
functions are define in st_sensors.h.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210823112204.243255-5-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 82bcb7fb 23-Aug-2021 Alexandru Ardelean <aardelean@deviqon.com>

iio: st_sensors: remove st_sensors_deallocate_trigger() function

This change converts the st_sensors_allocate_trigger() to use
device-managed functions.

The parent device of the IIO device object is used. This is based on the
assumption that all other devm_ calls in the ST sensors use this reference.

That makes the st_sensors_deallocate_trigger() function un-needed, so it
can be removed.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210823112204.243255-3-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 899f6791 20-Jul-2021 Alexandru Ardelean <aardelean@deviqon.com>

iio: magn: st_magn: use devm_iio_triggered_buffer_setup() for buffer

The st_magn_allocate_ring() function calls iio_triggered_buffer_setup() to
allocate a triggered buffer.

But the same can be done with devm_iio_triggered_buffer_setup() and then
the st_magn_common_remove() no longer needs to manually deallocate it.

We know that the parent of the IIO device is used to manage other instances
of the devm unwind, so it can be used in the st_magn_allocate_ring() as
well.

This change also removes some omitted st_magn_{probe,remove}_trigger()
inline hooks.

Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210720074642.223293-3-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 9c6cd755 08-Jun-2021 Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: st-sensors: Remove some unused includes and add some that should be there

The st-sensors drivers have changed in structure over time, and includes
have not always kept up with this. Let's bring them back to nearer
the ideal.

Identified with the include-what-you-use tool and careful checking of
its suggestions.

Note I haven't been particularly aggressive here, so this is just the
cases where the include obviously isn't needed rather than the more
subtle corners.

Note I took the opportunity to add mod_devicetable.h as I generally
prefer to see that when acpi or of match tables are present.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Denis Ciocca <denis.ciocca@st.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210608175149.4019289-1-jic23@kernel.org


# d5b92001 18-May-2021 Linus Walleij <linus.walleij@linaro.org>

iio: magnetometer: st_magn: Support mount matrix

Add support to read and present the mounting matrix on ST magnetometers.

Cc: Denis Ciocca <denis.ciocca@st.com>
Cc: Daniel Drake <drake@endlessm.com>
Cc: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210518230722.522446-4-linus.walleij@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 6731ca39 14-Apr-2021 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

iio: st_sensors: Add lsm9ds0 IMU support

We can utilize separate drivers for accelerometer and magnetometer,
so here is the glue driver to enable LSM9DS0 IMU support.

The idea was suggested by Crestez Dan Leonard in [1]. The proposed change
was sent as RFC due to race condition concerns, which are indeed possible.

In order to amend the initial change, I went further by providing a specific
multi-instantiate probe driver that reuses existing accelerometer and
magnetometer.

[1]: https://lore.kernel.org/patchwork/patch/670353/

Suggested-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Cc: mr.lahorde@laposte.net
Cc: Matija Podravec <matija_podravec@fastmail.fm>
Cc: Sergey Borishchenko <borischenko.sergey@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210414195454.84183-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 7db4f2ca 14-Apr-2021 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

iio: st_sensors: Call st_sensors_power_enable() from bus drivers

In case we would initialize two IIO devices from one physical device,
we shouldn't have a clash on regulators. That's why move
st_sensors_power_enable() call from core to bus drivers.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210414195454.84183-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 38934daf 14-Apr-2021 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

iio: magnetometer: st_magn: Provide default platform data

Provide default platform data for magnetometer in case it supports DRDY.

One case is LSM9DS0 IMU, on which it is the case. Since accelerometer
is using INT1, default magnetometer to INT2.

While at it, update description of the drdy_int_pin field.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210414195454.84183-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# c71cfe55 17-Mar-2021 LI Qingwu <Qing-wu.Li@leica-geosystems.com.cn>

iio:magnetometer: Add Support for ST IIS2MDC

Add support for ST magnetometer IIS2MDC,
an I2C/SPI interface 3-axis magnetometer.
The patch was tested on the instrument with IIS2MDC via I2C interface.

Signed-off-by: LI Qingwu <Qing-wu.Li@leica-geosystems.com.cn>
Link: https://lore.kernel.org/r/20210317063902.19300-3-Qing-wu.Li@leica-geosystems.com.cn
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 1f38527d 12-Mar-2020 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

iio: st_sensors: Drop unneeded explicit castings

In few places the unnecessary explicit castings are being used.
Drop them for good.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 12737476 23-Oct-2019 Linus Walleij <linus.walleij@linaro.org>

iio: st: Drop GPIO include

None of the ST sensor drivers use any symbols from
<linux/gpio.h>, just drop the include from all of them.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 9cd15d52 02-Aug-2019 Denis Ciocca <denis.ciocca@st.com>

iio: remove get_irq_data_ready() function pointer and use IRQ number directly

Not even sure why it was there since the beginning. Just use IRQ
number in the sensor_data struct.

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


# 062809ef 18-Jul-2019 Denis Ciocca <denis.ciocca@st.com>

iio: make st_sensors drivers use regmap

This patch is meant to replace the i2c/spi transfer functions with
regmap. SPI framework requires DMA safe buffers so let's add GFP_DMA
flag for memory allocation used by bulk_read functions.

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


# 1ecd245e 18-Jul-2019 Denis Ciocca <denis.ciocca@st.com>

iio: move 3-wire spi initialization to st_sensors_spi

Some devices need to be configured with special bit in order to
use spi 3-wire. This was done during device identification phase.
Instead, let's move this part as spi specific.
Doing this the check_device_support function becomes a simple
device id check, so let's rename it.

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


# aa4e75c8 18-Jul-2019 Denis Ciocca <denis.ciocca@st.com>

iio:magn: introduce st_magn_get_settings() function

The function is introduced to retrieve magn device settings. It will be
used by probe in order to configure regmap.

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


# fda8d26e 28-May-2019 Thomas Gleixner <tglx@linutronix.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 177

Based on 1 normalized pattern(s):

licensed under the gpl 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 135 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.071193225@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# 2eb4c9f2 25-Oct-2018 Martin Kelly <martin@martingkelly.com>

iio:magnetometer: st_magn: add BDU settings

LIS3MDL and LSM9DS1 are missing BDU settings in their register maps, so add
them. I don't have a LIS3MDL sensor to test, but this works correctly on
the LSM9DS1, which has the same register map.

Signed-off-by: Martin Kelly <martin@martingkelly.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 0d92aa2c 25-Oct-2018 Martin Kelly <martin@martingkelly.com>

iio:magnetometer: st_magn: add LSM9DS1 support

Update the sensor settings to support the LSM9DS1 sensor. Although the
LSM9DS1 accelerometer and gyroscope are coupled together to use the same
FIFO, the magnetometer is separate and can be cleanly supported without
refactoring the existing driver.

Signed-off-by: Martin Kelly <martin@martingkelly.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 2019738c 15-Oct-2018 Martin Kelly <martin@martingkelly.com>

iio: st_sensors: miscellaneous cleanup

Miscellaneous cleanup to fix minor consistency, grammar, and spelling
issues.

Signed-off-by: Martin Kelly <martin@martingkelly.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 9915c190 17-Sep-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: magnetometer: st_magn: add SPI-3wire support to LIS3MDL

Add SPI Serial Interface Mode (SIM) register information to
LIS3MDL magn sensor

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 75d4c6d2 30-Aug-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: st_sensors: decouple irq1 configuration parameters from the irq2 ones

Separate data-ready configuration parameters for INT1 and INT2 pins in
st_sensor_data_ready_irq data structure. That change will be use to
properly support LIS2DW12 accel sensor.

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# e72a0601 30-Aug-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: st_sensors: add register mask for status register

Introduce register mask for data-ready status register since
pressure sensors (e.g. LPS22HB) export just two channels
(BIT(0) and BIT(1)) and BIT(2) is marked reserved while in
st_sensors_new_samples_available() value read from status register
is masked using 0x7.
Moreover do not mask status register using active_scan_mask since
now status value is properly masked and if the result is not zero the
interrupt has to be consumed by the driver. This fix an issue on LPS25H
and LPS331AP where channel definition is swapped respect to status
register.
Furthermore that change allows to properly support new devices
(e.g LIS2DW12) that report just ZYXDA (data-ready) field in status register
to figure out if the interrupt has been generated by the device.

Fixes: 97865fe41322 (iio: st_sensors: verify interrupt event to status)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# c65e3d6e 29-Aug-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: magnetometer: st_magn: fix drdy line configuration for LIS3MDL

Data-ready line in LIS3MDL is routed to drdy pin and it is not possible
to select a different INT pin. st_sensors_set_dataready_irq() assumes
that if drdy int address is not exported in register map, irq trigger
is not supported by the sensor and hw_irq_trigger is always false.
Based on this configuration st_sensors_irq_thread does not consume
generated interrupt causing an unhandled irq.
Fix this taking into account status register address in
st_sensors_set_dataready_irq()

Fixes: 90efe0556292 (iio: st_sensors: harden interrupt handling)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 7f307262 23-Jul-2017 Jonathan Cameron <jic23@kernel.org>

iio:magnetometer: drop assign iio_info.driver_module and iio_trigger_ops.owner

The equivalent of both of these are now done via macro magic when
the relevant register calls are made. The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>


# 8b35a5f8 16-Aug-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: magnetometer: st_magn: remove ihl property for LSM303AGR

Remove IRQ active low support for LSM303AGR since the sensor does not
support that capability for data-ready line

Fixes: a9fd053b56c6 (iio: st_sensors: support active-low interrupts)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 541ee9b2 16-Aug-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: magnetometer: st_magn: fix status register address for LSM303AGR

Fixes: 97865fe41322 (iio: st_sensors: verify interrupt event to status)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# d0b7fea5 16-Aug-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: magnetometer: add support to LIS2MDL

add support to STMicroelectronics LIS2MDL magnetometer in
st_magn framework

http://www.st.com/resource/en/datasheet/lis2mdl.pdf
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


# 13718564 20-Jun-2017 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>

iio: magnetometer: st_magn_core: enable multiread by default for LIS3MDL

Enable multiread by default for LIS3MDL since using I2C interface
the subaddr Msb is used to automatically increase the slave address
during multiple data read/write. In the same way, using SPI interface,
bit 1 in register address is used to enable auto-increment of the slave
address in multiple read/write.

Fixes: 872e79add756 (iio:magn: Add STMicroelectronics magn driver)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 57d03554 09-Nov-2016 Linus Walleij <linus.walleij@linaro.org>

iio: magn: st_magn: inline per-sensor data

We have #defines for all the individual sensor registers and
value/mask pairs #defined at the top of the file and used at
exactly one spot.

This is usually good if the #defines give a meaning to the
opaque magic numbers.

However in this case, the semantic meaning is inherent in the
name of the C99-addressable fields, and that means duplication
of information, and only makes the code hard to maintain since
you every time have to add a new #define AND update the site
where it is to be used.

Get rid of the #defines and just open code the values into the
appropriate struct elements. Make sure to explicitly address
the .hz and .value fields in the st_sensor_odr_avl struct
so that the meaning of all values is clear.

This patch is purely syntactic should have no semantic effect.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 65925b65 21-May-2016 Linus Walleij <linus.walleij@linaro.org>

iio: st_sensors: switch to a threaded interrupt

commit 98ad8b41f58dff6b30713d7f09ae3834b8df7ded
("iio: st_sensors: verify interrupt event to status") caused
a regression when reading ST sensors from a HRTimer trigger
rather than the intrinsic interrupts: the HRTimer may
trigger faster than the sensor provides new values, and
as the check against new values available as a cause of
the interrupt trigger was done in the poll function,
this would bail out of the HRTimer interrupt with
IRQ_NONE.

So clearly we need to only check the new values available
from the proper interrupt handler and not from the poll
function, which should rather just read the raw values
from the registers, put them into the buffer and be happy.

To achieve this: switch the ST Sensors over to using a true
threaded interrupt handler.

In the interrupt thread, check if new values are available,
else yield to the (potential) next device on the same
interrupt line to check the registers. If the interrupt
was ours, proceed to poll the values.

Instead of relying on iio_trigger_generic_data_rdy_poll() as
a top half to wake up the thread that polls the sensor for
new data, have the thread call iio_trigger_poll_chained()
after determining that is is the proper source of the
interrupt. This is modelled on drivers/iio/accel/mma8452.c
which is already using a properly threaded interrupt handler.

In order to get the same precision in timestamps as
previously, where samples would be timestamped in the
poll function pf->timestamp when calling
iio_trigger_generic_data_rdy_poll() we introduce a
local timestamp in the sensor data, set it in the top half
(fastpath) of the interrupt handler and provide that to the
core when calling iio_push_to_buffers_with_timestamp().

Additionally: if the active scanmask is not set for the
sensor no IRQs should be enabled and we need to bail out
with IRQ_NONE. This can happen if spurious IRQs fire when
installing the threaded interrupt handler.

Tested with hard interrupt triggers on LIS331DL, then also
tested with hrtimers on the same sensor by creating a 75Hz
HRTimer and using it to poll the sensor.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Reported-by: Crestez Dan Leonard <cdleonard@gmail.com>
Tested-by: Crestez Dan Leonard <cdleonard@gmail.com>
Tested-by: Jonathan Cameron <jic23@kernel.org>
Fixes: 97865fe41322 ("iio: st_sensors: verify interrupt event to status")
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 14f295c8 19-Apr-2016 Gregor Boirie <gregor.boirie@parrot.com>

iio:st_sensors: fix power regulator usage

Ensure failure to enable power regulators is properly handled.

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 97865fe4 24-Mar-2016 Linus Walleij <linus.walleij@linaro.org>

iio: st_sensors: verify interrupt event to status

This makes all ST sensor drivers check that they actually have
new data available for the requested channel(s) before claiming
an IRQ, by reading the status register (which is conveniently
the same for all ST sensors) and check that the channel has new
data before proceeding to read it and fill the buffer.

This way sensors can share an interrupt line: it can be flaged
as shared and then the sensor that did not fire will return
NO_IRQ, and the sensor that fired will handle the IRQ and
return IRQ_HANDLED.

Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# a9fd053b 19-Nov-2015 Linus Walleij <linus.walleij@linaro.org>

iio: st_sensors: support active-low interrupts

Most ST MEMS Sensors that support interrupts can also handle sending
an active low interrupt, i.e. going from high to low on data ready
(or other interrupt) and thus triggering on a falling edge to the
interrupt controller.

Set up logic to inspect the interrupt line we get for a sensor: if
it is triggering on rising edge, leave everything alone, but if it
triggers on falling edges, set up active low, and if unsupported
configurations appear: warn with errors and reconfigure the interrupt
to a rising edge, which all interrupt generating sensors support.

Create a local header for st_sensors_core.h to share functions
between the sensor core and the trigger setup code.

Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# a0175b9c 12-Aug-2015 Linus Walleij <linus.walleij@linaro.org>

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>


# 1e9676a8 21-Jul-2015 Giuseppe Barba <giuseppe.barba@st.com>

iio: st-magn: add support for lsm303agr magnetometer

This adds support for the lsm303agr magnetometer.

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


# 74f5683f 21-Jul-2015 Giuseppe Barba <giuseppe.barba@st.com>

iio: st_magn: Add irq trigger handling

Add irq trigger handling for magnetometer also

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


# bc27381e 21-Jul-2015 Giuseppe Barba <giuseppe.barba@st.com>

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>


# 1038a687 30-Apr-2015 Linus Walleij <linus.walleij@linaro.org>

iio: magnetometer: support for lsm303dlh

The LSM303DLH accelerometer/magnetometer has a different
device identification method than using register 0x0f, instead
three registers contain a magic value. We rely on WhoAmI
to be zero for this variant.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 8e71c04f 20-Apr-2015 Alban Bedel <alban.bedel@avionic-design.de>

iio:st_sensors: Fix oops when probing SPI devices

In SPI mode the transfer buffer is locked with a mutex. However this
mutex is only initilized after the probe, but some transfer needs to
be done in the probe.

To fix this bug we move the mutex initialization at the beginning of
the device probe.

Signed-off-by: Alban Bedel <alban.bedel@avionic-design.de>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 2109eb4c 03-Oct-2014 Denis CIOCCA <denis.ciocca@st.com>

iio:magnetometer: Removed unnecessary parameter on common_probe function

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


# a7ee8839 03-Oct-2014 Denis CIOCCA <denis.ciocca@st.com>

iio:imu: changed structure name from st_sensors to st_sensor_settings

This patch change structure name and related variables names.

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


# a31d0928 09-Oct-2014 Denis CIOCCA <denis.ciocca@st.com>

iio:magnetometer: bugfix magnetometers gain values

This patch fix gains values. The first driver was designed using
engineering samples, in mass production the values are changed.

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


# 2d239c9e 22-Jun-2014 Jonathan Cameron <jic23@kernel.org>

iio:st sensors: remove custom sampling frequence attribute in favour of core support.

This allows in kernel client drivers to access this

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Cc: Denis Ciocca <denis.ciocca@st.com>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>


# ea7e586b 13-Apr-2014 Linus Walleij <linus.walleij@linaro.org>

iio: st_sensors: move regulator retrieveal to core

Currently the pressure sensor has code to retrieve and enable two
regulators for Vdd and Vdd IO, but actually these voltage inputs
are found on all of these ST sensors, so move the regulator
handling to the core and make sure all the ST sensors call these
functions on probe() and remove() to enable/disable power.

Here also mover over to obtaining the regulator from the *parent*
device of the IIO device, as the IIO device is created on-the-fly
in this very subsystem it very unlikely evert have any regulators
attached to it whatsoever. It is much more likely that the parent
is a platform device, possibly instantiated from a device tree,
which in turn have Vdd and Vdd IO supplied assigned to it.

Cc: Lee Jones <lee.jones@linaro.org>
Cc: Denis CIOCCA <denis.ciocca@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 4f544ced 13-Apr-2014 Linus Walleij <linus.walleij@linaro.org>

iio: st_sensors: announce registered sensors

It is pretty helpful to know already from dmesg that a certain
device is successfully registered, instead of having to browse
sysfs to see if it's actually there.

Cc: Lee Jones <lee.jones@linaro.org>
Cc: Denis CIOCCA <denis.ciocca@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 512690da 24-Sep-2013 Denis CIOCCA <denis.ciocca@st.com>

iio:magnetometer: Bugfix magnetometer default output registers

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


# f60b12b0 18-Sep-2013 Denis CIOCCA <denis.ciocca@st.com>

iio:magn: Register buffer also without specific trigger

This patch fix buffer registration that allows to use generic IIO trigger.

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


# 267a29b9 16-Sep-2013 Lee Jones <lee.jones@linaro.org>

iio: magn-core: st: Clean up error handling in probe()

Reduce the amount of those unnecessary goto calls, as in most cases
we can simply return immediately. We also only call for the IRQ number
once and use that value throughout.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 7fc5ad7e 02-Aug-2013 Sachin Kamat <sachin.kamat@linaro.org>

iio: magnetometer: st_magn: Use devm_iio_device_alloc

Using devm_iio_device_alloc makes code simpler.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>


# 23cde4d6 19-Jun-2013 Denis CIOCCA <denis.ciocca@st.com>

iio: Added ST-sensors platform data to select the DRDY interrupt pin

This patch add support to redirect the DRDY interrupt on INT1 or INT2
on accelerometer and pressure sensors.

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


# 607a568a 03-Jun-2013 Denis CIOCCA <denis.ciocca@st.com>

iio:common: Removed stuff macros, added num_data_channels on st_sensors struct and added support on one-shot sysfs reads to 3 byte channel

This patch introduce num_data_channels variable on st_sensors struct
to manage different type of channels (size or number) in
st_sensors_get_buffer_element function.
Removed ST_SENSORS_NUMBER_DATA_CHANNELS and ST_SENSORS_BYTE_FOR_CHANNEL
and used struct iio_chan_spec const *ch to catch data.
Added 3 byte channel data support on one-shot reads.

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


# 762011d6 03-Jun-2013 Denis CIOCCA <denis.ciocca@st.com>

iio:common: ST_SENSORS_LSM_CHANNELS macro changed

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


# 8ce4a56a 09-Feb-2013 Jonathan Cameron <jic23@kernel.org>

iio:st_sensors fix build when !CONFIG_IIO_TRIGGER

Partly a case of removing unused headers and partly a case
of ifdefing out the iio_trigger_ops structures. This has
come about because of an 'unusual' separation of code in this
driver.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Denis Ciocca <denis.ciocca@st.com>


# 872e79ad 25-Jan-2013 Denis Ciocca <denis.ciocca@gmail.com>

iio:magnetometer: Add STMicroelectronics magnetometers driver

This patch adds a generic magnetometer driver for STMicroelectronics
magnetometers, currently it supports:
LSM303DLHC, LSM303DLM, LIS3MDL.

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