Touchscreen on ARM with either evdev and libinupt

So, I've bought a touchscreen

input: 深圳市全动电子技术有限公司 ByQDtech 触控USB鼠标 as /devices/platform/soc@01c00000/1c14000.usb/usb3/3-1/3-1.4/3-1.4:1.0/0003:0483:5750.0004/input/input3

it's 7", it has USB touch (capacitive) able to register quite few fingers but lacks quite support on linux

I will post as I go on and uncover it's features and programs that enable it on Linux/GNU (Slackware).

Following this post will be a short report for how far I've got until now, and what needs be addressed yet.

The final goal:

1. Set up a portable computer with able to input text and run apps for standard X11
2. Android like handling of user input (in therms of on screen keyboard etc) but running XFCE4 or as similar to it as practical.
3. Support for 0/90/270/18 degree screen rotation
4. avoid patching any Slackware provided package if possible.

So far got it running, it draws ~500m more on the USB plug than the Banana Pi M1 without it. (so ~2.5W)
If the back light is switched off, it draws around 90mA instead

It registers proper with X11 and uses libinput as default driver.
The pointer responds smoothly but lacks right click emulation and any gestures (all reserved for touchpads only?)
If I make a file in

/etc/X11/xorg.conf.d

and code it as follows:

Section "InputClass"
    Identifier "switching to evdev"
    Driver "evdev"
#    Driver "libinput"
    MatchProduct "深圳市全动电子技术有限公司 ByQDtech 触控USB鼠标"

    MatchIsTouchscreen "on"

    Option "EmulateThirdButton" "1"
    Option "EmulateThirdButtonTimeout" "750"
    Option "EmulateThirdButtonMoveThreshold" "30"

EndSection

I even get right click on the Touchscreen, but, alas, the debounce is terrible so I get about 4 keypresses from the xvkbd.
I like xvkbd a bit better than the florence virtual keyboad that seems like more advanced but quite less stable option?

So far i found that evdev can be patched to have debounce:
Arch patches it by default?
But failed to find any way to trick libinput into "faking" a right click?

Stay tuned, or even better yet, do chime in and help?

May I ask what brand/model touchscreen you used and if progressed any further than your last post?

Originally Posted by justwantin May I ask what brand/model touchscreen you used and if progressed any further than your last post?

see the Chinese letters up there?

those are the brand :grin:

One might call it generic, but I would call it as written above.

Mine was bought form ebay, oddly enough the brand was not advertized.

I'd send you the ebay link (2017) but the seller is not registered any more and similar items won't work either.

Will provide you with additional photos later.

Thanks for the reply. Actually the brand is in that line. "QDtech". As far as I can tell QDtech is doing Waveshare knock offs. Waveshare touch screens seem to cost a bit more than the various Waveshare clones but they have a comprehensive wiki and supply images for various SBC's. As far as I can tell they are rolling a proprietary firmware driver for each board/system.

All the small touchscreens on Alibaba and Ebay seem to be targeting the RasberryPi family of SBC's. Waveshare supports other's such as Beagle Bone and Arduino Uno.

The kernel supports quite a few touchscreen chips. Device Drivers → Input device support → Touchscreens

I recon most of those kernel modules are for chips used in industrial or point of sale touchscreens/applications.

The project I am considering would work with a 10" screen (Waveshare has a 10.1"). I'm almost pushing something sized for an industrial application so I suppose I'll have to work down the line of chips supported by the kernel looking for a touch screen to fit my budget.

Cheers

Originally Posted by justwantin Thanks for the reply. Actually the brand is in that line. "QDtech". As far as I can tell QDtech is doing Waveshare knock offs. Waveshare touch screens seem to cost a bit more than the various Waveshare clones but they have a comprehensive wiki and supply images for various SBC's. As far as I can tell they are rolling a proprietary firmware driver for each board/system. All the small touchscreens on Alibaba and Ebay seem to be targeting the RasberryPi family of SBC's. Waveshare supports other's such as Beagle Bone and Arduino Uno. The kernel supports quite a few touchscreen chips. Device Drivers → Input device support → Touchscreens I recon most of those kernel modules are for chips used in industrial or point of sale touchscreens/applications. The project I am considering would work with a 10" screen (Waveshare has a 10.1"). I'm almost pushing something sized for an industrial application so I suppose I'll have to work down the line of chips supported by the kernel looking for a touch screen to fit my budget. Cheers

In hope of feedback (if/when you succeed):

Cheers

I'll post something when I have something to post. Right now I'll be reading up on linux touchscreens. As usually there is a preponderance as raspberry pi stuff to wade through before I can find something relevant to my interest. Maybe it will be simpler than I expect. Number one problem seems to me to be that peripheral hardware listings these days rarely provide info on chips used.

Right click can be simulated with a long press.