Patch "iio: hid-sensor: Store restore poll and hysteresis on S3" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    iio: hid-sensor: Store restore poll and hysteresis on S3

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     iio-hid-sensor-store-restore-poll-and-hysteresis-on-s3.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 5d9854eaea776441b38a9a45b4e6879524c4f48c Mon Sep 17 00:00:00 2001
From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Date: Fri, 7 Apr 2017 17:13:17 -0700
Subject: iio: hid-sensor: Store restore poll and hysteresis on S3

From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

commit 5d9854eaea776441b38a9a45b4e6879524c4f48c upstream.

This change undo the change done by 'commit 3bec24747446
("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: 3bec24747446 ("iio: hid-sensor-trigger: Change get poll value function order to avoid sensor properties losing after resume from S3")
Reported-by: Ritesh Raj Sarraf <rrs@researchut.com>
Tested-by: Ritesh Raj Sarraf <rrs@researchut.com>
Tested-by: Song, Hongyan <hongyan.song@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/iio/common/hid-sensors/hid-sensor-attributes.c |   26 +++++++++++++++--
 drivers/iio/common/hid-sensors/hid-sensor-trigger.c    |   20 +++++++++++--
 include/linux/hid-sensor-hub.h                         |    2 +
 3 files changed, 43 insertions(+), 5 deletions(-)

--- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
+++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
@@ -217,7 +217,15 @@ int hid_sensor_write_samp_freq_value(str
 	if (ret < 0 || value < 0)
 		ret = -EINVAL;
 
-	return ret;
+	ret = sensor_hub_get_feature(st->hsdev,
+				     st->poll.report_id,
+				     st->poll.index, sizeof(value), &value);
+	if (ret < 0 || value < 0)
+		return -EINVAL;
+
+	st->poll_interval = value;
+
+	return 0;
 }
 EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);
 
@@ -259,7 +267,16 @@ int hid_sensor_write_raw_hyst_value(stru
 	if (ret < 0 || value < 0)
 		ret = -EINVAL;
 
-	return ret;
+	ret = sensor_hub_get_feature(st->hsdev,
+				     st->sensitivity.report_id,
+				     st->sensitivity.index, sizeof(value),
+				     &value);
+	if (ret < 0 || value < 0)
+		return -EINVAL;
+
+	st->raw_hystersis = value;
+
+	return 0;
 }
 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
 
@@ -355,6 +372,9 @@ int hid_sensor_get_reporting_interval(st
 	/* Default unit of measure is milliseconds */
 	if (st->poll.units == 0)
 		st->poll.units = HID_USAGE_SENSOR_UNITS_MILLISECOND;
+
+	st->poll_interval = -1;
+
 	return 0;
 
 }
@@ -377,6 +397,8 @@ int hid_sensor_parse_common_attributes(s
 					HID_USAGE_SENSOR_PROY_POWER_STATE,
 					&st->power_state);
 
+	st->raw_hystersis = -1;
+
 	sensor_hub_input_get_attribute_info(hsdev,
 			HID_FEATURE_REPORT, usage_id,
 			HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
--- a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
+++ b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
@@ -51,6 +51,8 @@ static int _hid_sensor_power_state(struc
 			st->report_state.report_id,
 			st->report_state.index,
 			HID_USAGE_SENSOR_PROP_REPORTING_STATE_ALL_EVENTS_ENUM);
+
+		poll_value = hid_sensor_read_poll_value(st);
 	} else {
 		int val;
 
@@ -87,9 +89,7 @@ static int _hid_sensor_power_state(struc
 	sensor_hub_get_feature(st->hsdev, st->power_state.report_id,
 			       st->power_state.index,
 			       sizeof(state_val), &state_val);
-	if (state)
-		poll_value = hid_sensor_read_poll_value(st);
-	if (poll_value > 0)
+	if (state && poll_value)
 		msleep_interruptible(poll_value * 2);
 
 	return 0;
@@ -127,6 +127,20 @@ static void hid_sensor_set_power_work(st
 	struct hid_sensor_common *attrb = container_of(work,
 						       struct hid_sensor_common,
 						       work);
+
+	if (attrb->poll_interval >= 0)
+		sensor_hub_set_feature(attrb->hsdev, attrb->poll.report_id,
+				       attrb->poll.index,
+				       sizeof(attrb->poll_interval),
+				       &attrb->poll_interval);
+
+	if (attrb->raw_hystersis >= 0)
+		sensor_hub_set_feature(attrb->hsdev,
+				       attrb->sensitivity.report_id,
+				       attrb->sensitivity.index,
+				       sizeof(attrb->raw_hystersis),
+				       &attrb->raw_hystersis);
+
 	_hid_sensor_power_state(attrb, true);
 }
 
--- a/include/linux/hid-sensor-hub.h
+++ b/include/linux/hid-sensor-hub.h
@@ -231,6 +231,8 @@ struct hid_sensor_common {
 	unsigned usage_id;
 	atomic_t data_ready;
 	atomic_t user_requested_state;
+	int poll_interval;
+	int raw_hystersis;
 	struct iio_trigger *trigger;
 	struct hid_sensor_hub_attribute_info poll;
 	struct hid_sensor_hub_attribute_info report_state;


Patches currently in stable-queue which might be from srinivas.pandruvada@linux.intel.com are

queue-4.9/iio-hid-sensor-store-restore-poll-and-hysteresis-on-s3.patch