patch "iio: hid-sensor-attributes: Fix sensor property setting failure." added to staging-linus

[<gregkh@linuxfoundation.org>]

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

    iio: hid-sensor-attributes: Fix sensor property setting failure.

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From bba6d9e47f3ea894e501f94b086a59ffe28241ac Mon Sep 17 00:00:00 2001
From: Song Hongyan <hongyan.song@intel.com>
Date: Tue, 28 Mar 2017 22:23:55 +0800
Subject: iio: hid-sensor-attributes: Fix sensor property setting failure.

When system bootup without get sensor property, set sensor
property will be fail.

If no get_feature operation done before set_feature, the sensor
properties will all be the initialized value, which is not the
same with sensor real properties. When set sensor property it will
write back to sensor the changed perperty data combines with other
sensor properties data, it is not right and may be dangerous.

In order to get all sensor properties, choose to read one of the sensor
properties(no matter read any sensor peroperty, driver will get all
the peroperties and return the requested one).

Fixes: 73c6768b710a ("iio: hid-sensors: Common attribute and trigger")
Signed-off-by: Song Hongyan <hongyan.song@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/common/hid-sensors/hid-sensor-attributes.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
index 7afdac42ed42..01e02b9926d4 100644
--- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
+++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c
@@ -379,6 +379,8 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 {
 
 	struct hid_sensor_hub_attribute_info timestamp;
+	s32 value;
+	int ret;
 
 	hid_sensor_get_reporting_interval(hsdev, usage_id, st);
 
@@ -417,6 +419,14 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 		st->sensitivity.index, st->sensitivity.report_id,
 		timestamp.index, timestamp.report_id);
 
+	ret = sensor_hub_get_feature(hsdev,
+				st->power_state.report_id,
+				st->power_state.index, sizeof(value), &value);
+	if (ret < 0)
+		return ret;
+	if (value < 0)
+		return -EINVAL;
+
 	return 0;
 }
 EXPORT_SYMBOL(hid_sensor_parse_common_attributes);
-- 
2.12.1