It has been reported for a while that with iio-sensor-proxy service the
rotation only works after one suspend/resume cycle. This required a wait
in the systemd unit file to avoid race. I found a Yoga 900 where I could
reproduce this.

The problem scenerio is:
- During sensor driver init, enable run time PM and also set a
  auto-suspend for 3 seconds.
	This result in one runtime resume. But there is a check to avoid
a powerup in this sequence, but rpm is active
- User space iio-sensor-proxy tries to power up the sensor. Since rpm is
  active it will simply return. But sensors were not actually
powered up in the prior sequence, so actaully the sensors will not work
- After 3 seconds the auto suspend kicks

If we add a wait in systemd service file to fire iio-sensor-proxy after
3 seconds, then now everything will work as the runtime resume will
actually powerup the sensor as this is a user request.

To avoid this:
- Remove the check to match user requested state, this will cause a
  brief powerup, but if the iio-sensor-proxy starts immediately it will
still work as the sensors are ON.
- Also move the autosuspend delay to place when user requested turn off
  of sensors, like after user finished raw read or buffer disable
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: NBastien Nocera <hadess@hadess.net>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>

HID sensor hubs using Integrated Senor Hub (ISH) has added capability to
support batch mode. This allows host processor to go to sleep for extended
duration, while the sensor hub is storing samples in its internal buffers.

'Commit f4f4673b ("iio: add support for hardware fifo")' implements
feature in IIO core to implement such feature. This feature is used in
bmc150-accel-core.c to implement batch mode. This implementation allows
software device buffer watermark to be used as a hint to adjust hardware
FIFO.

But HID sensor hubs don't allow to change internal buffer size of FIFOs.
Instead an additional usage id to set "maximum report latency" is defined.
This allows host to go to sleep upto this latency period without getting
any report. Since there is no ABI to set this latency, a new attribute
"hwfifo_timeout" is added so that user mode can specify a latency.

This change checks presence of usage id to get/set maximum report latency
and if present, it will expose hwfifo_timeout.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

When a hid sensor module is removed and modprobed again we see
error for unbalanced pm_runtime. This issue is caused by not
deactivating runtime PM on removal. So on modprobe again when
activated again, this will print this error.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

This change undo the change done by 'commit 3bec2474
("iio: hid-sensor-trigger: Change get poll value function order to avoid
sensor properties losing after resume from S3")' as this breaks some
USB/i2c sensor hubs.

Instead of relying on HW for restoring poll and hysteresis, driver stores
and restores on resume (S3). In this way user space modified settings are
not lost for any kind of sensor hub behavior.

In this change, whenever user space modifies sampling frequency or
hysteresis driver will get the feature value from the hub and store in the
per device hid_sensor_common data structure. On resume callback from S3,
system will set the feature to sensor hub, if user space ever modified the
feature value.

Fixes: 3bec2474 ("iio: hid-sensor-trigger: Change get poll value function order to avoid sensor properties losing after resume from S3")
Reported-by: NRitesh Raj Sarraf <rrs@researchut.com>
Tested-by: NRitesh Raj Sarraf <rrs@researchut.com>
Tested-by: NSong, Hongyan <hongyan.song@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

iio: hid-sensor-trigger: Change get poll value function order to avoid sensor properties losing after resume from S3

In function _hid_sensor_power_state(), when hid_sensor_read_poll_value()
is called, sensor's all properties will be updated by the value from
sensor hardware/firmware.
In some implementation, sensor hardware/firmware will do a power cycle
during S3. In this case, after resume, once hid_sensor_read_poll_value()
is called, sensor's all properties which are kept by driver during S3
will be changed to default value.
But instead, if a set feature function is called first, sensor
hardware/firmware will be recovered to the last status. So change the
sensor_hub_set_feature() calling order to behind of set feature function
to avoid sensor properties lose.
Signed-off-by: NSong Hongyan <hongyan.song@intel.com>
Acked-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

A small rework of the PM code in this driver introduced a harmless
warning when CONFIG_PM_SLEEP is not set:

drivers/iio/common/hid-sensors/hid-sensor-trigger.c:212:12: error: 'hid_sensor_resume' defined but not used [-Werror=unused-function]

This removes the #ifdef and instead marks all three PM functions
as __maybe_unused, which covers all possible cases and is harder
to get wrong.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: 7f6cf741 ("iio: hid-sensors: use asynchronous resume")
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Some platforms power off sensor hubs during S3 suspend, which will require
longer time to resume. This hurts system resume time, so resume
asynchronously.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

This fixes the error reported by checkpatch.pl:

ERROR: code indent should use tabs where possible
Signed-off-by: NSlawomir Stepien <sst@poczta.fm>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

By default all the sensors are runtime suspended state (lowest power
state). During Linux suspend process, all the run time suspended
devices are resumed and then suspended. This caused all sensors to
power up and introduced delay in suspend time, when we introduced
runtime PM for HID sensors. The opposite process happens during resume
process.

To fix this, we do powerup process of the sensors only when the request
is issued from user (raw or tiggerred). In this way when runtime,
resume calls for powerup it will simply return as this will not match
user requested state.

Note this is a regression fix as the increase in suspend / resume
times can be substantial (report of 8 seconds on Len's laptop!)
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: NLen Brown <len.brown@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

By default all the sensors are runtime suspended state (lowest power
state). During Linux suspend process, all the run time suspended
devices are resumed and then suspended. This caused all sensors to
power up and introduced delay in suspend time, when we introduced
runtime PM for HID sensors. The opposite process happens during resume
process.

To fix this, we do powerup process of the sensors only when the request
is issued from user (raw or tiggerred). In this way when runtime,
resume calls for powerup it will simply return as this will not match
user requested state.

Note this is a regression fix as the increase in suspend / resume
times can be substantial (report of 8 seconds on Len's laptop!)
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: NLen Brown <len.brown@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Current API only allows setting one offset in the field. This API
is extended to set multiple offsets in the field report.
Also update parameters in the users of this API.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Some hid sensor feature report can contain more than one reports.
This API can now support receiving multiple values from the feature
report.
Also update the parameters in the users of this API.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

To improvement power and performance, both regular and run time callbacks
are introduced. Because of auto suspend delay, two consecutive read
don't have to go through full power on/off procedure. The auto suspend
time can be adjusted using regular power attributes of PM sysfs.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

This can result in wrong reference count for trigger device, call
iio_trigger_get to increment reference.
Refer to http://www.spinics.net/lists/linux-iio/msg13669.html for discussion
with Jonathan.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Cc: Stable@vger.kernel.org

Some sensor hubs require a get feature report call to be issued soon after
changing the power state of the sensor. Without this, the sensor remains in
the current state. This patch adds a call soon after the power state.

This is retained as a generic call across all sensor hubs since the behavior
has been noticed on more than one implementation.
Signed-off-by: NArchana Patni <archana.patni@intel.com>
Signed-off-by: NSubramony Sesha <subramony.sesha@intel.com>
Reviewed-by: NSrinivas Pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Added an API to allow client drivers to turn ON and OFF sensors for
quick read. Added data_read as counting varaible instead of boolean,
so that sensor is powered off only when last user released it.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Remove the hard coded indexes, instead search for usage id and
use the index to set the power and report state.
This will fix issue, where the report descriptor doesn't contain
the full list of possible selector for power and report state.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

In the original HID sensor hub firmwares all Named array enums were
to 0-based. But the most recent hub implemented as 1-based,
because of the implementation by one of the major OS vendor.
Using logical minimum for the field as the base of enum. So we add
logical minimum to the selector values before setting those fields.
Some sensor hub FWs already changed logical minimum from 0 to 1
to reflect this and hope every other vendor will follow.
There is no easy way to add a common HID quirk for NAry elements,
even if the standard specifies these field as NAry, the collection
used to describe selectors is still just "logical".
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

We can't store the trigger instance created by iio_trigger_alloc, in
trig field of iio_device structure. This needs to be stored in the
driver private data. Othewise it can result in crash during module
unload. Hence created a trig_ptr in the common data structure
for each HID sensor IIO driver and storing here.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Call hid_sensor_hub_device_open when user space opens device and call
hid_sensor_hub_device_close when device is closed. This helps in
saving power.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Introduce iio_tigger_{set,get}_drvdata which allows to attach driver specific
data to a trigger. The functions wrap access to the triggers private_data field
and all current users are updated to use iio_tigger_{set,get}_drvdata instead of
directly accessing the private_data field. This is the first step towards
removing the private_data field from the iio_trigger struct.

The following coccinelle script has been used to update the drivers:
<smpl>
@@
struct iio_trigger *trigger;
expression priv;
@@
-trigger->private_data = priv
+iio_trigger_set_drv_data(trigger, priv)

@@
struct iio_trigger *trigger;
@@
-trigger->private_data
+iio_trigger_get_drv_data(trigger)
</smpl>
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The structure with common attributes for hid-sensors isn't specific
to the iio-subsystem, so rename it to hid_sensor_common.
Signed-off-by: NAlexander Holler <holler@ahsoftware.de>
Acked-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The stuff in hid-sensor-attributes.h is needed by every piece which
uses hid-sensor-hub and merging it into hid-sensor-hub.h makes it accessible
from outside the iio subdirectory.
Signed-off-by: NAlexander Holler <holler@ahsoftware.de>
Acked-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

It's non-sense to use tristate for the option, it's bool.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

When hid sensor hub is unplugged, there is a crash in
iio_device_unregister_trigger_consumer.
In a typical IIO driver when remove is called, it will unregister and free
trigger and then it will call iio_device_free.
The function iio_trigger_free() will free the allocated memory for trigger.
If this trigger was assigned to iio_dev->trig, then it should be set to NULL.
Othewise when iio_device_free() is called later, it finally calls
iio_device_unregsister_trigger(), which checks for
       if (indio_dev->trig)
                iio_trigger_put(indio_dev->trig);
If indio_dev->trig is not set to NULL, it calls iio_trigger_put on a bad
pointer causing crash.
This scenerio can happen in any driver, which is storing trigger pointer in
iio_dev structure and following current procedure during remove.
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

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