Srinivas Pandruvada ad7532cefd iio: hid-sensor-trigger: Don't touch sensors unless user space requests ... One of the user complained that on his system Thinkpad Yoga S1, with commit f1664eaace ("iio: hid-sensor-trigger: Fix the race with user space powering up sensors") causes the system to resume immediately on suspend (S3 operation). On this system the sensor hub is on USB and is a wake up device from S3. So if any sensor sends data on motion, the system will wake up. This can be a legitimate use case to wake up device motion, but that needs proper user space support to set right thresholds. In fact the above commit didn't cause this regression, but any operation which cause sensors to wake up would have caused the same issue. So if user reads the raw sensor data, same issue occurs, with or without this commit. Only difference is that the above commit by default will trigger a power up and power down of sensors as part of runtime pm enable (runtime enable will cause a runtime resume callback followed by runtime_suspend callback). Previously user has to do some action on sensors. On investigation it was observed that the current driver correctly changing the state of all sensors to power off but then also some sensor will still send some data. Only option is to never power up any sensor. Only good option is to: - Using sysfs interface disable USB as a wakeup device (This will not need any driver change) Since some user don't care about sensors. So for those users this change brings back old functionality. As long as they don't cause any operation to power up sensors (like raw read or start iio-sensor-proxy service), the sensors will not be to touched. This is done by delaying run time enable till user space does some operation with sensors. Link: https://bugzilla.kernel.org/show_bug.cgi?id=196853 Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>		2017-10-14 19:29:50 +01:00
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hid-sensor-attributes.c	HID: hid-sensor-hub: Force logical minimum to 1 for power and report state	2017-08-09 22:15:59 +02:00
hid-sensor-trigger.c	iio: hid-sensor-trigger: Don't touch sensors unless user space requests	2017-10-14 19:29:50 +01:00
hid-sensor-trigger.h	iio: hid_sensor_hub: Common PM functions	2015-01-25 22:55:39 +00:00
Kconfig	iio hid-sensor-trigger: add Kconfig depends on IIO_BUFFER	2017-06-13 21:10:14 +01:00
Makefile	iio: hid-sensors: respect CONFIG_IIO_TRIGGER	2012-12-27 10:59:50 +00:00