Re: [PATCH 2/9] Input: atmel_mxt_ts - use deep sleep mode when stopped

[Nick Dyer <nick.dyer@itdev.co.uk>]

On 11/08/15 15:24, Nick Dyer wrote:
> On 10/08/15 21:11, Benjamin Tissoires wrote:
>> I am currently running v4.2-rc6, merged with Dmitry's and Jiri's tree.
>> This patch completely kills my touchpad on the Pixel 2. No touch
>> information is sent while the physical button still emits values. You
>> said that you tested it on this laptop too, so I wonder why mine
>> refuses to work.
> 
> I'm just building that version to see if I can reproduce. Dmitry made some
> minor changes when he merged it, but I don't think it should have affected
> anything.
> 
> Are you able to send me some dmesg output with dyndbg=+pt enabled?
> 
> It would also be useful if you could compile mxt-app and try issuing a
> calibrate or reset command to see if that restores touch (let me know if
> you need instructions).

I've done some testing and I believe I'm able to reproduce your issue. It
appears to be caused by a bad calibration, i.e. if I run the following
command then the touchpad starts working:

sudo ./mxt-app -d i2c-dev:0-004a --calibrate

(it times out waiting for the calibration complete message when in i2c-dev
mode, but that's expected)

Could you verify this at your end?

The patch under discussion sends a calibrate command as the input device is
opened. However I can see that user space is opening/closing the device 3x
in the space of about a second as X starts up, which may be confusing the
firmware. It might be that we need to wait for the calibration to complete,
I will try adding some code to do that.