iio: cros: Register FIFO callback after sensor is registered

Instead of registering callback to process sensor events right at
initialization time, wait for the sensor to be register in the iio
subsystem.

Events can come at probe time (in case the kernel rebooted abruptly
without switching the sensor off for instance), and be sent to IIO core
before the sensor is fully registered.

Fixes: aa984f1ba4a4 ("iio: cros_ec: Register to cros_ec_sensorhub when EC supports FIFO")
Reported-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20220711144716.642617-1-gwendal@chromium.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: common: cros_ec_sensors: Add label attribute

When sensor location is known, populate iio sysfs "label" attribute:

* "accel-base" : the sensor is in the base of the convertible (2-1)
device.
* "accel-display" : the sensor is in the lid/display plane of the
device.
* "accel-camera" : the sensor is in the swivel camera subassembly.

The non-standard |location| attribute is removed, the field |loc| in
cros_ec_sensors_core_state is removed.

It apply to standalone accelerometer as well as IMU (accelerometer +
gyroscope) and sensors where the location is known (light).

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Link: https://lore.kernel.org/r/20220427190804.961697-3-gwendal@chromium.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: cros_ec_sensors: Fix alignment of buffer in iio_push_to_buffers_with_timestamp()

The samples buffer is passed to iio_push_to_buffers_with_timestamp()
which requires a buffer aligned to 8 bytes as it is assumed that
the timestamp will be naturally aligned if present.

Fixes tag is inaccurate but prior to that likely manual backporting needed
(for anything before 4.18) Earlier than that the include file to fix is
drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.h:
commit 974e6f02e27 ("iio: cros_ec_sensors_core: Add common functions
for the ChromeOS EC Sensor Hub.") present since kernel stable 4.10.
(Thanks to Gwendal for tracking this down)

Fixes: 5a0b8cb46624c ("iio: cros_ec: Move cros_ec_sensors_core.h in /include")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org
Link: https://lore.kernel.org/r/20210501171352.512953-7-jic23@kernel.org

iio: cros: unify hw fifo attributes without API changes

Commit 2e2366c2d141 ("iio: cros_ec: unify hw fifo attributes into the core file")
should be reverted as it set buffer extended attributes at
the wrong place. However, to revert it will requires to revert more
commits:
commit 165aea80e2e2 ("iio: cros_ec: use devm_iio_triggered_buffer_setup_ext()")
commit 21232b4456ba ("iio: buffer: remove iio_buffer_set_attrs() helper")).
and we would still have conflict with more recent development.
commit ee708e6baacd ("iio: buffer: introduce support for attaching more IIO buffers")

Instead, this commit reverts the first 2 commits without re-adding
iio_buffer_set_attrs() and set the buffer extended attributes at the
right place:

1. Instead of adding has_fw_fifo, deduct it from the configuration:
- EC must support FIFO (EC_FEATURE_MOTION_SENSE_FIFO) set.
- sensors send data a regular interval (accelerometer, gyro,
magnetomer, barometer, light sensor).
- "Legacy accelerometer" is only present on EC without FIFO, so we don't
need to set buffer attributes.

2. devm_iio_triggered_buffer_setup_ext() does not need to be called when
EC does not support FIFO, as there is no FIFO to manage.

3. Use devm_iio_triggered_buffer_setup_ext() when EC has a FIFO to
specify the buffer extended attributes.

Fixes: 2e2366c2d141 ("iio: cros_ec: unify hw fifo attributes into the core file")
Fixes: 165aea80e2e2 ("iio: cros_ec: use devm_iio_triggered_buffer_setup_ext()")
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210318184857.2679181-1-gwendal@chromium.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: cros_ec: unify hw fifo attributes into the core file

The intent here is to minimize the use of iio_buffer_set_attrs(). Since we
are planning to add support for multiple IIO buffers per IIO device, the
issue has to do with:
1. Accessing 'indio_dev->buffer' directly (as is done with
'iio_buffer_set_attrs(indio_dev->buffer, <attrs>)').
2. The way that the buffer attributes would get handled or expanded when
there are more buffers per IIO device. Current a sysfs kobj_type expands
into a 'device' object that expands into an 'iio_dev' object.
We will need to change this, so that the sysfs attributes for IIO
buffers expand into IIO buffers at some point.

Right now, the current IIO framework works fine for the
'1 IIO device == 1 IIO buffer' case (that is now).

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Link: https://lore.kernel.org/r/20200923130339.997902-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: cros_ec: Reapply range at resume

EC does not currently preserve range across sensor reinit.
If sensor is powered down at suspend, it will default to the EC default
range at resume, not the range set by the host.

Save range if modified, and apply at resume.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: cros_ec: Use Hertz as unit for sampling frequency

To be compliant with other sensors, set and get sensor sampling
frequency in Hz, not mHz.

Fixes: ae7b02ad2f32 ("iio: common: cros_ec_sensors: Expose cros_ec_sensors frequency range via iio sysfs")
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

iio: cros_ec: Report hwfifo_watermark_max

Report the maximum amount of sample the EC can hold.
This is not tunable, but can be useful for application to find out the
maximum amount of time it can sleep when hwfifo_timeout is set to a
large number.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

iio: cros_ec: Expose hwfifo_timeout

Expose EC minimal interrupt period through buffer/hwfifo_timeout:
- Maximal timeout is limited to 65s.
- When timeout for all sensors is set to 0, EC will not send events,
even if the sensor sampling rate is greater than 0.

Rename frequency to sampling_frequency to match IIO ABI.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

iio: cros_ec: Remove pm function

Since cros_ec_sensorhub is shutting down the FIFO when the device
suspends, no need to slow down the EC sampling period rate.

It was necesseary to do that before command CMD_FIFO_INT_ENABLE was
introduced, but now all supported chromebooks have it.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

iio: cros_ec: Register to cros_ec_sensorhub when EC supports FIFO

When EC supports FIFO, each IIO device registers a callback, to put
samples in the buffer when they arrives from the FIFO.

When no FIFO, the user space app needs to call trigger_new, or better
register a high precision timer.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

iio: cros_ec: Move function description to .c file

To prevent comment rot, move function description to
cros_ec_sensors_core.c.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

mfd / platform: cros_ec: Reorganize platform and mfd includes

There is a bit of mess between cros-ec mfd includes and platform
includes. For example, we have a linux/mfd/cros_ec.h include that
exports the interface implemented in platform/chrome/cros_ec_proto.c. Or
we have a linux/mfd/cros_ec_commands.h file that is non related to the
multifunction device (in the sense that is not exporting any function of
the mfd device). This causes crossed includes between mfd and
platform/chrome subsystems and makes the code difficult to read, apart
from creating 'curious' situations where a platform/chrome driver includes
a linux/mfd/cros_ec.h file just to get the exported functions that are
implemented in another platform/chrome driver.

In order to have a better separation on what the cros-ec multifunction
driver does and what the cros-ec core provides move and rework the
affected includes doing:

- Move cros_ec_commands.h to include/linux/platform_data/cros_ec_commands.h
- Get rid of the parts that are implemented in the platform/chrome/cros_ec_proto.c
driver from include/linux/mfd/cros_ec.h to a new file
include/linux/platform_data/cros_ec_proto.h
- Update all the drivers with the new includes, so
- Drivers that only need to know about the protocol include
- linux/platform_data/cros_ec_proto.h
- linux/platform_data/cros_ec_commands.h
- Drivers that need to know about the cros-ec mfd device also include
- linux/mfd/cros_ec.h

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Series changes: 3
- Fix dereferencing pointer to incomplete type 'struct cros_ec_dev' (lkp)
Signed-off-by: Lee Jones <lee.jones@linaro.org>

iio: common: cros_ec_sensors: Expose cros_ec_sensors frequency range via iio sysfs

Embedded controller return minimum and maximum frequencies, unfortunately
we have no way to know the step for all available frequencies.
Even if not complete, we can return a list of known values using the
standard read_avail callback (IIO_CHAN_INFO_SAMP_FREQ) to provide them to
userland.

Now cros_ec_* sensors provides frequencies values in sysfs like this:
"0 min max". 0 is always true to disable the sensor.

Default frequencies are provided for earlier protocol.

Signed-off-by: Nick Vaccaro <nvaccaro@chromium.org>
Signed-off-by: Fabien Lahoudere <fabien.lahoudere@collabora.com>
[rebased on top of iio/testing and solved conflicts]
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: cros_ec: Add sign vector in core for backward compatibility

To allow cros_ec iio core library to be used with legacy device, add a
vector to rotate sensor data if necessary: legacy devices are not
reporting data in HTML5/Android sensor referential.

Check the data is not rotated on recent chromebooks that use the HTML5
standard to present sensor data.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: cros_ec: Add calibscale for 3d MEMS

Add calibration scale support to accel, gyro and magnetometer.

Check on eve with current firmware, check reading calibscale returns 1.0,
check with newer firmware values are applied.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

Based on 1 normalized pattern(s):

this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: cros_ec: Move cros_ec_sensors_core.h in /include

Similar to other common iio frameworks, move cros_ec_sensors_core.h from
drivers/iio/common/cros_ec_sensors/ to include/linux/iio/common.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>