Re: [PATCH] HID: Add quirk for Lenovo Yoga 910 with ITE Chips

[Arek Burdach <arek.burdach@gmail.com>]

On 16.07.2017 12:23, Brian Masney wrote:
> On Sun, Jul 16, 2017 at 09:39:19AM +0200, Arek Burdach wrote:
>> Hi Patrick,
>>
>> On 15.07.2017 14:27, Patrick Pedersen wrote:
>>> It shall additionally be noted that the i2c-hid 'sleep' bug (present since kernel ver. 4.3)
>>> still affects the driver. This means that the sensor hub will not report any movement, until
>>> the device is suspended and resumed.
>>>
>> Do you have workaround for that? In my case suspending and resuming doesn't
>> help. Sensor reporting is backing to work in unpredictable way. What I've
>> tested:
>>
>> - kernel v4.13-rc1 with your patch applied
>> - watch -n1 cat /sys/bus/iio/devices/iio\:device*/*_raw <- value not
>> changing
>> - suspend
>> - resume
>> - watch -n1 cat /sys/bus/iio/devices/iio\:device*/*_raw <- still not
>> changing
>>
>> If you have some workaround scenario please add it to bug reported be me:
>> https://bugzilla.kernel.org/show_bug.cgi?id=195681
> I have a Lenovo Yoga 910-13IKB
So do I
>   and verified that the patch works
> correctly for me on an upstream 4.12 kernel. The ALS sensor and
> accelerometer function correctly without suspending the laptop with
> this patch. The difference may be due the following kernel boot options
> that I use:
>
> 	i915.enable_rc6=0 pci=noaer intel_pstate=disable
>
> I have to disable power management for the CPU/GPU (i915.enable_rc6=0)
> since I can only suspend and resume once on this laptop. Suspending a
> second time will cause the laptop to hang before the suspend finishes.
>
> The pci=noaer is likely not needed for UEFI firmware revisions 2JCN36WW
> and newer. I'm stuck on UEFI firmware revision 2JCN28WW, which is what
> came preinstalled on the system. Lenovo's UEFI update tool requires
> Windows, which I no longer have.
>
> I need to get on the latest UEFI revision and go through
> basic-pm-debugging.txt if the power management issues are still present.
I have installed 2JCN36WW and: pci=noaer intel_pstate=disable flags are 
never need - suspending works ok every time.

I investigated that having iio-sensor-proxy installed may cause sensors 
stopping to work. Looks like only one option can work in the same time - 
either iio-sensor-proxy service or sensor reporting of raw data.

Arek