Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1585079

Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation

From "H. Nikolaus Schaller" <hns@goldelico.com>
Newsgroups linux.kernel
Subject Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation
Date 2017-02-21 08:00 +0100
Message-ID <tdcAz-7lC-17@gated-at.bofh.it> (permalink)
References (3 earlier) <td3nA-1p5-9@gated-at.bofh.it> <td3GV-1vZ-13@gated-at.bofh.it> <td49X-1GG-15@gated-at.bofh.it> <td4CZ-26B-11@gated-at.bofh.it> <td4CZ-26B-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw

Hi Dmitry,

> Am 20.02.2017 um 23:24 schrieb Dmitry Torokhov <dmitry.torokhov@gmail.com>:
> 
> On Mon, Feb 20, 2017 at 2:21 PM, Petr Cvek <petr.cvek@tul.cz> wrote:
>> Hi,
>> 
>> Dne 20.2.2017 v 22:50 Dmitry Torokhov napsal(a):
>>> On Mon, Feb 20, 2017 at 1:27 PM, H. Nikolaus Schaller <hns@goldelico.com> wrote:
>>>> 
>>>>> Am 20.02.2017 um 22:08 schrieb Pali Rohár <pali.rohar@gmail.com>:
>>>>> 
>>>>> On Monday 20 February 2017 20:42:15 Pali Rohár wrote:
>>>>>> Hi Nikolaus!
>>>>>> 
>>>>>> On Monday 20 February 2017 17:50:04 H. Nikolaus Schaller wrote:
>>>>>>> Hi Dmitry,
>>>>>>> 
>>>>>>>> Input driver may set resolution for given axis in units per mm
>>>>>>>> (or units per radian for rotational axis ABS_RX, ABS_RY,
>>>>>>>> ABS_RZ), and if you check the binding, you can use
>>>>>>>> "touchscreen-x-mm" and "touchscreen-y-mm" to specify the size of
>>>>>>>> entire touch surface and set resolution from it so that
>>>>>>>> userspace can calculate the proper scaling factor.
>>>>>>> 
>>>>>>> How is this information exposed by the kernel to user-space? By
>>>>>>> scanning the DT file or tree?
>>>>>> 
>>>>>> Set input_abs_set_res() from kernel. And in userspace call EVIOCGABS
>>>>>> ioctl() on input device. Look at struct input_absinfo, you should
>>>>>> have all needed information here. This is generic input interface,
>>>>>> no DT is needed.
>>>>> 
>>>>> Looking at kernel code... via EVIOCSABS ioctl() you can even set
>>>>> resolution from userspace for specified input device.
>>>>> 
>>>>> So this could be potentially used for calibrating input device from
>>>>> userspace? (In case DT data will not fully match current HW)
>>>>> 
>>>>>> I hope that XServer is already using it for evdev devices...
>>>>>> 
>>>>>> For whole implementation look at evtest program. That should be good
>>>>>> starting point for your userspace implementation.
>>>>>> 
>>>>>> While I'm watching this discussion... in my opinion kernel should
>>>>>> just invert input axes (when needed)
>>>> 
>>>> It is questionable why it should do that at all then.
>>> 
>>> Because the task of the kernel is to provide unified view of the
>>> hardware. Axis swapping and inversion is needed to that "up" is always
>>> "up" and "right" is always "right".
>> 
>> Actually my Xorg calibration 3x3 matrix is fine with both axis inverted (on TSC2046).
> 
> Yes, you can make it work for your touchscreen as long as you know
> that it inverted somehow. How you gain this knowledge is the question.

I think by letting the user calibrate the touch (calib tools can detect
inversion and rotation by the tap gesture sequence). I got the impression
that this step is wanted anyways for getting maximum precision.

Or the user-space configuration for a specific device model knows that because
the developer has gained this knowledge once and predefined the rotation matrix
for e.g. X11 correctly. If he didn't e.g. for Replicant it is Replicant's bug...

So you do not need this knowledge passed to user-space at all. Hence my proposal
to get rid of touch inversion and flipping properties and code from the touch
screen drivers.

BR and thanks,
Nikolaus

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Dmitry Torokhov <dmitry.torokhov@gmail.com> - 2017-02-17 21:50 +0100
  Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Sebastian Reichel <sre@kernel.org> - 2017-02-18 04:30 +0100
    Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-18 12:40 +0100
      Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Sebastian Reichel <sre@kernel.org> - 2017-02-19 00:50 +0100
        Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-19 13:10 +0100
          Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Sebastian Reichel <sre@kernel.org> - 2017-02-19 21:20 +0100
            Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 18:00 +0100
  Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new  common binding names, pre-calibration, flipping and rotation Andreas Kemnade <andreas@kemnade.info> - 2017-02-18 09:20 +0100
  Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-18 10:20 +0100
    Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-18 12:40 +0100
      Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-18 19:10 +0100
        Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-18 20:30 +0100
          Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 00:00 +0100
            Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-19 13:10 +0100
              Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 15:20 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-19 18:10 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 18:20 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-19 19:00 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 20:10 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-19 20:40 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 22:00 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-19 23:10 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 23:30 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 18:00 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-20 20:30 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 21:30 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Petr Cvek <petr.cvek@tul.cz> - 2017-02-20 23:30 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-21 09:40 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new  common binding names, pre-calibration, flipping and rotation Andreas Kemnade <andreas@kemnade.info> - 2017-02-19 23:40 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new  common binding names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-19 23:50 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 18:00 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new  common binding names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-20 20:40 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 21:30 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 22:00 +0100
  Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-18 12:40 +0100
    Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Dmitry Torokhov <dmitry.torokhov@gmail.com> - 2017-02-20 02:20 +0100
      Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 18:00 +0100
        Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-20 20:50 +0100
          Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 21:40 +0100
            Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-20 22:10 +0100
              Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 22:30 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-20 23:00 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-21 07:50 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-21 10:00 +0100
          Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-20 22:10 +0100
            Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-20 22:30 +0100
              Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Dmitry Torokhov <dmitry.torokhov@gmail.com> - 2017-02-20 23:00 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Dmitry Torokhov <dmitry.torokhov@gmail.com> - 2017-02-20 23:30 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-21 08:00 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Petr Cvek <petr.cvek@tul.cz> - 2017-02-20 23:40 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-20 23:50 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-21 07:40 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-21 10:10 +0100
                Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new  common binding names, pre-calibration, flipping and rotation Andreas Kemnade <andreas@kemnade.info> - 2017-02-21 18:20 +0100
              Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-20 23:10 +0100
                Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-21 08:00 +0100
          Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation "H. Nikolaus Schaller" <hns@goldelico.com> - 2017-02-21 08:20 +0100
            Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pali Rohár <pali.rohar@gmail.com> - 2017-02-21 09:50 +0100
              Re: [Letux-kernel] [PATCH v9 1/8] drivers:input:tsc2007: add new  common binding names, pre-calibration, flipping and rotation Christ van Willegen <cvwillegen@gmail.com> - 2017-02-21 10:00 +0100
        Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding  names, pre-calibration, flipping and rotation Pavel Machek <pavel@ucw.cz> - 2017-02-21 12:10 +0100

csiph-web