Commit Graph

20 Commits

Author SHA1 Message Date
Linus Walleij 166365273f iio: magnetometer: ak8974: Provide scaling
The manual for the HSCDTD008A gives us a scaling for the
three axis as +/- 2.4mT (24 Gauss) per axis.

The manual for the AMI305 and AMI306 gives us a scaling
for the three axis as +/- 12 Gauss per axis.

Tests with the HSCDTD008A sensor, cat the raw values:
$ cat in_magn_*_raw
raw
45
189
-19

The scaling factor in in_magn_*_scale is 0.001464843,
which gives:
0.065 Gauss
0.277 Gauss
-0.027 Gauss

The earths magnetic field is in the range of 0.25 to 0.65
Gauss on the surface according to Wikipedia, so these
seem like reasonable values.

Again we are guessing that the AK8974 has a 12 bit ADC,
based on the similarity with AMI305 and AMI306.

Cc: Nick Reitemeyer <nick.reitemeyer@web.de>
Cc: Stephan Gerhold <stephan@gerhold.net>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-05-03 09:47:22 +01:00
Linus Walleij 55ecaf1717 iio: magnetometer: ak8974: Break out measurement
This breaks out the measurement code to its own function
so we can handle this without swirling it up with the
big switch() statement inside ak8974_read_raw().

Keep a local s16 helper variable for the signed value
coming out of the measurement before assigning it to the
integer *val. The local variable makes the code easier
to read and the compiler will optimize it if possible.

Cc: Nick Reitemeyer <nick.reitemeyer@web.de>
Cc: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-05-03 09:47:22 +01:00
Linus Walleij b67959eba4 iio: magnetometer: ak8974: Correct realbits
The HSCDTD008A has 15 bits of actual ADC valie, and the
AMI305 and AMI306 has 12 bits.

Correct this by providing an extra parameter to the channel
macro and define a separate set of channels for each variant
of the chip. The resolution is the actual resolution of the
internal ADC of the chip.

The values are stored in a S16 in 2's complement so all 16
bits are used for storing (no shifting needed).

The AMI305, AMI306 and HSCDTD008A valid bits are picked from
respective datasheet.

My best educated guess is that AK8974 is also 12 bits. The
AK8973 is an 8 bit and earlier version, and the sibling
drivers AMI305 and AMI306 are 12 bits, so it makes sense
to assume that the AK8974 is also 12 bits.

Cc: Nick Reitemeyer <nick.reitemeyer@web.de>
Cc: Stephan Gerhold <stephan@gerhold.net>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-05-03 09:47:22 +01:00
Nick Reitemeyer 525530af77 iio: magnetometer: ak8974: add Alps hscdtd008a
The hscdtd008a is similar to the AK8974:
Only the whoami value and some registers are different.

Signed-off-by: Nick Reitemeyer <nick.reitemeyer@web.de>
Reviewed-by: Stephan Gerhold <stephan@gerhold.net>
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-05-03 09:47:22 +01:00
Greg Kroah-Hartman 4e1d96306d First set of new IIO device support, features and cleanup for the 5.8 cycle
Usual mix of new drivers, new support in old drivers and lots of minor
 cleanup. Yaml conversions also continue to trickle in (plenty more to go!)
 
 New device support
 * ad7476
   - Add ad7091 support (ID only)
 * ad9467
   - New driver for this 200/250 MSPS adi-axi-adc and SPI attached ADC.
 * adi-axi-adc
   - New driver to support ADIs generic AXI ADC IP core, used to provide
     high speed interfaces to ADCs (JESD204B/C or parallel interfaces). Usually
     paired with a device using a slow configuration interface (spi etc)
     Includes DT bindings and some fixes for fpga headers.
 * bmg160
   - Add support for BMI088 (ID only)
 * max1241
   - New driver for this ADC.
 * st_sensors
   - Add support for LIS2HH12 accelerometer
 * sx9310
   - New driver supporting sx9310 and sx9311 proximity sensors.
 
 Yaml DT binding conversions
 * rockchip-saradc (including adding some missing parts)
 * stm32-dac
 * tsl2563
 * vcnl4000
 
 Features
 * st_lsm6dsx
   - Add LIS3MDL as a possible sensor hub device.
 * vcnl4000
   - Add new concept of near level (from DT) to provide to userspace which
     often needs to have some calibrated concept of 'near'.
 
 Cleanups, minor fixes etc.
 * core
   - Use snprintf for functions where strings are built and there is
     potential for overflow.
   - Correct docs to indicate mlock should not be used directly by drivers.
   - Fix up accidental dropping of a patch to use bitmap_zalloc.
   - Stop allowing enabling of buffers with no channels enabled.
   - Drop unused 'stufftoread' from iio_buffer.
   - Drop scan_el_attrs form iio_buffer as unused.
   - Reorder sanity checks in __iio_device_register to fail earlier.
   - Drop all the devm_ runregister / free functions from IIO as they
     were never used and encourage poor design.
 * dma-buffer
   - Tidy up includes.
 * dma-engine-buffer
   - Provide dev-managed allocator.
   - Fix an issue with printing a size_t
 * cross subsystem (kxsd9, bmg160, mpu3050, bmi160, mpu6050, bmc150)
   - Replace some unnecessary casts of error ptrs and whilst there.
     use the %pe printf parameter to print them in a more useful fashion.
 * cross subsystem
   - Drop casts in calls to regmap_bulk_read as they make no sense.
   - Use devm_platform_ioremap_resource to reduce boilerplate.
   - Fix typos in Analog Devices.
 * counters/104-quad
   - Add Syed Nayyar Waris as an additional maintainer.
 * ad7476
   - Generate CONVST signal internally rather than requiring external
     trigger.  Add sysfs read back as can now do so.
   - use devm_add_action_or_reset to tidy up error and remove handling.
 * ad7793
   - Switch to read_avail from explicit attribute. Mostly done to avoid
     confusing people with a - sign (without surounding spaces) that
     was correct but checkpatch didn't like.
 * adis library
   - Add missing newlines at end of error messages.
 * adis16400
   - Use DEFINE_DEBUGS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTR.
 * adis16460
   - Use DEFINE_DEBUGS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTR.
 * ad_sigma_delta
   - Move some channel definitions into individual drivers to avoid
     having to deal with complex options.
 * ak8974
   - Silence an error on deffered probe.
 * bmp280
   - Harden against IRQ before registration.
   - Convert to read_avail instead of opencoding the equivalent.
   - Explicitly mark GPIO as optional.
   - Cleanup casts.
   - Remove line breaks from strings.
 * htts221
   - Replace direct access to platform_data with dev_get_platdata().
   - Use device properties rather than device tree ones to allow ACPI
     probing.
   - Casting cleanups.
 * intel_mrfld_adc
   - Don't use unaligned accessor for aligned data.
 * isl29125
   - Reorder buer pre and post hooks to allow for coming core rework.
 * ltc2983
   - Remove comp to bool.
 * max1363
   - Stop using mlock from the iio_dev directly in favour of a local lock
     with clearly defined scope.
 * max30100
   - Use generic device properties to allow ACPI probe.
 * mpu6050
   - Convert to i2c_new_client_device.
   - Add debugfs register access.
 * st_lsm6dsx
   - Provide means of configuring full scale on slave device if supported.
   - Drop include of st_sensors header to get one value. Its not otherwise
     used by this driver.
 * st-sensors
   - Replace direct access to platform_data with dev_get_platdata().
   - Casting cleanups.
   - Avoid splitting strings.
 * st_uvis25
   - Casting cleanups.
 * tsl2563
   - Typo fix.
 * tsl2772
   - scnprintf in a non obvious string building usecase. Note also 'fixes'
     a wrong calculation of remaining space that couldn't actually cause
     any trouble as there was lots of room.
 * xilinx-xadc
   - Fix Lars-Peter spelling his own name wrong :) + additional typos.
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Merge tag 'iio-for-5.8a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First set of new IIO device support, features and cleanup for the 5.8 cycle

Usual mix of new drivers, new support in old drivers and lots of minor
cleanup. Yaml conversions also continue to trickle in (plenty more to go!)

New device support
* ad7476
  - Add ad7091 support (ID only)
* ad9467
  - New driver for this 200/250 MSPS adi-axi-adc and SPI attached ADC.
* adi-axi-adc
  - New driver to support ADIs generic AXI ADC IP core, used to provide
    high speed interfaces to ADCs (JESD204B/C or parallel interfaces). Usually
    paired with a device using a slow configuration interface (spi etc)
    Includes DT bindings and some fixes for fpga headers.
* bmg160
  - Add support for BMI088 (ID only)
* max1241
  - New driver for this ADC.
* st_sensors
  - Add support for LIS2HH12 accelerometer
* sx9310
  - New driver supporting sx9310 and sx9311 proximity sensors.

Yaml DT binding conversions
* rockchip-saradc (including adding some missing parts)
* stm32-dac
* tsl2563
* vcnl4000

Features
* st_lsm6dsx
  - Add LIS3MDL as a possible sensor hub device.
* vcnl4000
  - Add new concept of near level (from DT) to provide to userspace which
    often needs to have some calibrated concept of 'near'.

Cleanups, minor fixes etc.
* core
  - Use snprintf for functions where strings are built and there is
    potential for overflow.
  - Correct docs to indicate mlock should not be used directly by drivers.
  - Fix up accidental dropping of a patch to use bitmap_zalloc.
  - Stop allowing enabling of buffers with no channels enabled.
  - Drop unused 'stufftoread' from iio_buffer.
  - Drop scan_el_attrs form iio_buffer as unused.
  - Reorder sanity checks in __iio_device_register to fail earlier.
  - Drop all the devm_ runregister / free functions from IIO as they
    were never used and encourage poor design.
* dma-buffer
  - Tidy up includes.
* dma-engine-buffer
  - Provide dev-managed allocator.
  - Fix an issue with printing a size_t
* cross subsystem (kxsd9, bmg160, mpu3050, bmi160, mpu6050, bmc150)
  - Replace some unnecessary casts of error ptrs and whilst there.
    use the %pe printf parameter to print them in a more useful fashion.
* cross subsystem
  - Drop casts in calls to regmap_bulk_read as they make no sense.
  - Use devm_platform_ioremap_resource to reduce boilerplate.
  - Fix typos in Analog Devices.
* counters/104-quad
  - Add Syed Nayyar Waris as an additional maintainer.
* ad7476
  - Generate CONVST signal internally rather than requiring external
    trigger.  Add sysfs read back as can now do so.
  - use devm_add_action_or_reset to tidy up error and remove handling.
* ad7793
  - Switch to read_avail from explicit attribute. Mostly done to avoid
    confusing people with a - sign (without surounding spaces) that
    was correct but checkpatch didn't like.
* adis library
  - Add missing newlines at end of error messages.
* adis16400
  - Use DEFINE_DEBUGS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTR.
* adis16460
  - Use DEFINE_DEBUGS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTR.
* ad_sigma_delta
  - Move some channel definitions into individual drivers to avoid
    having to deal with complex options.
* ak8974
  - Silence an error on deffered probe.
* bmp280
  - Harden against IRQ before registration.
  - Convert to read_avail instead of opencoding the equivalent.
  - Explicitly mark GPIO as optional.
  - Cleanup casts.
  - Remove line breaks from strings.
* htts221
  - Replace direct access to platform_data with dev_get_platdata().
  - Use device properties rather than device tree ones to allow ACPI
    probing.
  - Casting cleanups.
* intel_mrfld_adc
  - Don't use unaligned accessor for aligned data.
* isl29125
  - Reorder buer pre and post hooks to allow for coming core rework.
* ltc2983
  - Remove comp to bool.
* max1363
  - Stop using mlock from the iio_dev directly in favour of a local lock
    with clearly defined scope.
* max30100
  - Use generic device properties to allow ACPI probe.
* mpu6050
  - Convert to i2c_new_client_device.
  - Add debugfs register access.
* st_lsm6dsx
  - Provide means of configuring full scale on slave device if supported.
  - Drop include of st_sensors header to get one value. Its not otherwise
    used by this driver.
* st-sensors
  - Replace direct access to platform_data with dev_get_platdata().
  - Casting cleanups.
  - Avoid splitting strings.
* st_uvis25
  - Casting cleanups.
* tsl2563
  - Typo fix.
* tsl2772
  - scnprintf in a non obvious string building usecase. Note also 'fixes'
    a wrong calculation of remaining space that couldn't actually cause
    any trouble as there was lots of room.
* xilinx-xadc
  - Fix Lars-Peter spelling his own name wrong :) + additional typos.

* tag 'iio-for-5.8a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (101 commits)
  iio: magnetometer: ak8974: Silence deferred-probe error
  Documentation: ABI: document IIO in_proximity_nearlevel file
  iio: vcnl4000: Export near level property for proximity sensor
  dt-bindings: iio: light: vcnl4000: Add proximity-near-level
  dt-bindings: iio: Introduce common properties for iio sensors
  dt-bindings: iio: vcnl4000: convert bindings to YAML format
  iio: Fix misspellings of "Analog Devices"
  iio: light: isl29125: fix iio_triggered_buffer_{predisable,postenable} positions
  iio: adc: fsl-imx25-gcq: Use devm_platform_ioremap_resource
  iio: adc: at91-adc: Use devm_platform_ioremap_resource
  iio: adc: sun4i-gpadc-iio: Use devm_platform_ioremap_resource
  iio:light:ltr501: Drop unnecessary cast of parameter in regmap_bulk_read
  iio:magn:mmc35240: Drop unnecessary casts of val parameter in regmap_bulk*
  iio:imu:mpu6050: Tidy up parameters to regmap_bulk functions.
  iio:chemical:bme680: Tidy up parameters to regmap_bulk_read
  iio:chemical:atlas-sensor: Drop unnecessary explicit casts in regmap_bulk_read calls
  iio:accel:mxc4005: Drop unnecessary explicit casts in regmap_bulk_read calls
  iio: imu: st_lsm6dsx: drop huge include in sensor-hub driver
  iio: buffer: drop devm_iio_kfifo_free() API call
  iio: buffer: drop devm_iio_hw_consumer_free() API call
  ...
2020-04-23 11:06:48 +02:00
Dmitry Osipenko 2de8c02349 iio: magnetometer: ak8974: Silence deferred-probe error
It's not uncommon that voltage regulator becomes available later during
kernel's boot process. This patch adds info message about unavailable
regulators in a case of the deferred-probe error and also amends the
error message with a error code.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-04-19 16:56:43 +01:00
Stephan Gerhold b500c086e4 iio: magnetometer: ak8974: Fix negative raw values in sysfs
At the moment, reading from in_magn_*_raw in sysfs tends to return
large values around 65000, even though the output of ak8974 is actually
limited to ±32768. This happens because the value is never converted
to the signed 16-bit integer variant.

Add an explicit cast to s16 to fix this.

Fixes: 7c94a8b2ee ("iio: magn: add a driver for AK8974")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Waleij <linus.walleij@linaro.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-02-21 11:59:46 +00:00
Thomas Gleixner 09c434b8a0 treewide: Add SPDX license identifier for more missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

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>
2019-05-21 10:50:45 +02:00
Andy Shevchenko fb1589710e iio: Allow to read mount matrix from ACPI
Currently mount matrix is allowed in Device Tree, though there is
no technical issue to extend it to support ACPI.

Convert the function to use device_property_read_string_array() and
thus allow to read mount matrix from ACPI if available.

Example of use in _DSD method:

  Name (_DSD, Package ()
  {
     ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
     Package ()
     {
        Package () { "mount-matrix", Package() {
                "1", "0",     "0",
                "0", "0.866", "0.5",
                "0", "-0.5",  "0.866",
        } },
     }
  })

At the same time drop the "of" prefix from its name and
convert current users.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-04-04 20:19:46 +01:00
Jonathan Cameron 7f307262af 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>
2017-08-22 21:32:52 +01:00
Michał Mirosław 0a60340f19 iio: magnetometer: ak8974: debug AMI306 calibration data
Use AMI306 calibration data for randomness and debugging.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-08-20 15:41:11 +01:00
Michał Mirosław 9991f99eed iio: magnetometer: ak8974: mark INT_CLEAR as precious
Reading INT_CLEAR has side effects - disallow reading it via debugfs.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-08-20 15:17:39 +01:00
Michał Mirosław 408cc6eb1e iio: magnetometer: ak8974: add_device_randomness (serial number)
Mix device-specific data into randomness pool.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-08-20 15:17:27 +01:00
Michał Mirosław 21be26fc67 iio: magnetometer: ak8974: support AMI306 variant
Add support for AMI306 magnetometer - very similar to AMI305.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-08-20 11:18:33 +01:00
Dmitry Torokhov 3ff861f59f iio: magnetometer: ak8974: remove incorrect __exit markups
Even if bus is not hot-pluggable, devices can be unbound from the
driver via sysfs, so we should not be using __exit annotations on
remove() methods. The only exception is drivers registered with
platform_driver_probe() which specifically disables sysfs bind/unbind
attributes.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-03-05 13:52:01 +00:00
Colin Ian King e2eb179c00 iio: magnetometer: ak8974: remove redundant zero timeout check
At the end of the delay loop timeout will always be zero
and hence the check for !timeout will always be true. Remove
the redundant check and the redundant return 0 at the end of
the function.

Fixes CoverityScan CID#1357168 ("Logically dead code")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2017-01-14 13:10:04 +00:00
Ico Doornekamp 7f709dcda4 iio: magnetometer: ak8974: small endianness fixes
Fixes two cases of 'cast to restricted __le16' as reported by sparse.

Signed-off-by: Ico Doornekamp <ico@pruts.nl>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-10-03 21:30:00 +01:00
Wei Yongjun 96303e2027 iio: magn: ak8974: remove .owner field for driver
Remove .owner field if calls are used which set it automatically.

Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-29 20:12:10 +01:00
Arnd Bergmann 5bc55ef31f iio: magn/ak8974: avoid unused function warning
The ak8974_configure() function is used only from the PM code,
but that can be hidden when CONFIG_PM is disabled:

drivers/iio/magnetometer/ak8974.c:201:12: error: 'ak8974_configure' defined but not used [-Werror=unused-function]

This replaces the #ifdef with a __maybe_unused annotation, which
will work correctly in all configurations and avoid the warning,
as the compiler can now see where ak8974_configure is called from.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 7c94a8b2ee ("iio: magn: add a driver for AK8974")
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-29 19:54:55 +01:00
Linus Walleij 7c94a8b2ee iio: magn: add a driver for AK8974
This adds a driver for the Asahi Kasei AK8974 and its sibling
AMI305 magnetometers. It was deployed on scale in 2009 on a
multitude of devices. It is distincly different from AK8973
and AK8975 and needs its own driver.

This patch is based on the long lost work of Samu Onkalo at Nokia,
who made a misc character device driver for the Maemo/MeeGo Nokia
devices, before the time of the IIO subsystem. It was mounted in e.g.
the Nokia N950, N8, N86, N97 etc. It is also mounted on the
ST-Ericsson HREF reference designs.

It works nicely in sysfs:

$ cat in_magn_x_raw && cat in_magn_y_raw && cat in_magn_z_raw
-55
-101
161

And with buffered reads using a simple HRTimer trigger:
$ generic_buffer -c10 -a -n ak8974 -t foo
iio device number being used is 3
iio trigger number being used is 2
No channels are enabled, enabling all channels
Enabling: in_magn_x_en
Enabling: in_magn_y_en
Enabling: in_magn_z_en
Enabling: in_timestamp_en
/sys/bus/iio/devices/iio:device3 foo
-58.000000 -102.000000 157.000000 946684970985321044
-60.000000 -98.000000 159.000000 946684971012237548
-60.000000 -106.000000 163.000000 946684971032257080
-62.000000 -94.000000 169.000000 946684971052185058
-58.000000 -98.000000 163.000000 946684971072204589
-54.000000 -100.000000 163.000000 946684971092224121
-53.000000 -103.000000 164.000000 946684971112731933
-50.000000 -102.000000 165.000000 946684971132232666
-61.000000 -101.000000 164.000000 946684971152191162
-57.000000 -99.000000 168.000000 946684971172210693
Disabling: in_magn_x_en
Disabling: in_magn_y_en
Disabling: in_magn_z_en
Disabling: in_timestamp_en

I cannot currently scale these raw values to gauss. This is
because of lack of documentation. I have sent a request for
a datasheet to Asahi Kasei.

The driver can optionally use a DRDY line IRQ to capture data,
else it will sleep and poll.

Cc: Samu Onkalo <samu.onkalo@intel.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Tested-By: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-08-15 16:49:39 +01:00