Switching to a touchscreen ?

I am working on getting a 10” capacitive multitouch screen going that runs on one channel LVDS (so it should work well with Novena). I have a supplier lined up, just need to generate interest to do a big enough order. The touch controller speaks USB and I have confirmed that it works out-of-the-box with the Linux kernel shipped with Novena.

There are five holes on the eDP board that connect to an STMPE810 port expander chip.  Specifically, it connects to the touchscreen controller.

So you could, if you want, hook up a resistive panel.

Incidentally, the ADC from the STMPE is connected to the headphone port, in case you want to add support for headsets with volume buttons.

If your captouch board speaks USB, you can also use the USB port present on the breakout board.

You might try contacting Crowd Supply about eDP boards.

I'm also personally interested in learning how much it costs

Estimated per-unit cost for the displays is 150 USD (depends a bit on shipping and duty things, etc).

Well, it will require at least enough technical skill to take the eDP board off, hook up to a single LVDS channel, and set the kernel to output to a single LVDS channel with the right settings. So, similar to hooking up any other panel, pretty much, I hope

Yes, that panel should work.

There isn't [yet] a flag, but one could be created!  It'd be a device tree entry.

Actually, now that I look at it, support is almost there, but a typo has prevented it from actually working.  The documentation is at https://github.com/xobs/novena-linux/bl … /stmpe.txt and the device tree file is at https://github.com/xobs/novena-linux/bl … a.dts#L343

I'd recommend giving the 3.19 build a go, and then building a new device tree.  Edit arch/arm/boot/dts/imx6q-novena.dts, change the "compatible" line to match stmpe.txt (i.e. make it "st,stmpe-ts"), then run "make dtbs" and copy arch/arm/boot/dts/imx6q-novena.dtb to /boot/novena.dtb.

The 3.19 debs are at https://nas.xobs.io/novena/20150902/ and I'll be releasing them through the repo soon.

the "UU" means that the kernel is using the part, meaning it's "Unavailable" to userspace.  It looks like you changed the wrong field.

The STMPE is a bit of a weird device.  It's called a MultiFunction Device, and falls into the MFD section.  It is an umbrella device which as one physical part and multiple logical parts.  That's because it's a touchscreen controller, keypad, GPIO device, and ADC.  You pick which parts you want by configuring sub-devices.

The section should look something like this:

        stmpe811@44 {
                compatible = "st,stmpe811";
                reg = <0x44>;
                #address-cells = <1>;
                #size-cells = <0>;
                irq-gpio = <&gpio5 13 GPIO_ACTIVE_HIGH>;
                id = <0>;
                blocks = <0x5>;
                irq-trigger = <0x1>;
                pinctrl-names = "default";
                pinctrl-0 = <&pinctrl_stmpe_novena>;
                vio-supply = <&reg_3p3v>;
                vcc-supply = <&reg_3p3v>;

                stmpe_touchscreen {
                        compatible = "st,stmpe-ts";
                        st,sample-time = <4>;
                        st,mod-12b = <1>;
                        st,ref-sel = <0>;
                        st,adc-freq = <1>;
                        st,ave-ctrl = <1>;
                        st,touch-det-delay = <2>;
                        st,settling = <2>;
                        st,fraction-z = <7>;
                        st,i-drive = <1>;
                };
        };

My failed attempt at attempting to compile the stmpe-ts module from source is as follows:

Cloned xob's git repository and ensured that branch v3.19-novena-etnadrm-r3 was checked out.

Edited arch/arm/configs/novena_defconfig and made the following changes:

CONFIG_TOUCHSCREEN_USB_COMPOSITE=m       ->      CONFIG_TOUCHSCREEN_USB_COMPOSITE=y
...
# CONFIG_TOUCHSCREEN_STMPE is not set        ->      CONFIG_TOUCHSCREEN_STMPE=m

executed the following commands:

$ make novena_defconfig && make modules_prepare && make modules M=drivers/input/touchscreen

This generated stmpe-ts.ko file inside drivers/input/touchscreen. However, insmod returned an "invalid module format" error.
modinfo revealed that the version number 'vermagic' field was

3.19.0-00468-g53b6c5d-dirty

, which did not match my native precompiled and installed kernel (i.e., the output of

uname -r

).

I can change the vermagic field by changing the contents of include/config/kernel.release and include/generated/utsrelease.h files manually before generating modules, but the insmod error remains.

Is there a way around this issue?

Regarding -dirty, I usually make this hack to get around that:

diff --git a/scripts/setlocalversion b/scripts/setlocalversion
index 63d91e2..4d24d6a 100755
--- a/scripts/setlocalversion
+++ b/scripts/setlocalversion
@@ -73,9 +73,9 @@ scm_version()
                fi
 
                # Check for uncommitted changes
-               if git diff-index --name-only HEAD | grep -qv "^scripts/package"; then
-                       printf '%s' -dirty
-               fi
+#              if git diff-index --name-only HEAD | grep -qv "^scripts/package"; then
+#                      printf '%s' -dirty
+#              fi
 
                # All done with git
                return

And... that's a good catch.  I can't believe I forgot to enable the STMPE touchscreen module.  That would be why it's not working.  I'll build those in so that the touchscreen will work for you.