Bluetooth page turning for Kobo eReaders

[byrhias]

Originally Posted by Renate

My religious principles prevent me from long-pressing anything.
If a short press does not work there is no need to persist.

Lol I made do with what I had but you do you.

[akadaedalus]

TL;DR: If you don't get an input device on the LIbra 2, you aren't necessarily out of luck. You just need another kernel module. Read on...

Originally Posted by akadaedalus

My dog ate my working remote ring so I ordered a few more on aliexpress. I figured I'd try different kinds since I don't like the stretch rubber on the original ring.

I found most of them simply don't work in Kobo and I suspect it needs a separate kernel driver similar to the uhid module. I haven't had the time to figure it out.

A linux pc makes it easier to test, but you really need to remote into the reader and run evtest from there to see what it detects.

So I never got around to this until my dog ate another one. After considering selling the dog instead of buying another clicker, I decided to revisit setting up the ones I purchased before. Aliexpress may not ship to the US any more.

Looking at the Linux dmesg logs I could see that the clicker called "ZL-03" Amazon link was being loaded as an Apple device. That is why it never showed up in evtest on the Kobo.

The solution was to follow tylpk1216's instructions except to build the hid-apple.ko module. That's

CONFIG_HID_APPLE=m

in the kernel .config. The cross compiling needs a little bit more work depending on which LD binary you have installed.

The device does 'BTN_TOUCH' on all three buttons but you can hold the up arrow for repeat volume up, and you can hold the down arrow for repeat volume down. This works for skimming back and forth.

I've got a five-button device that I haven't been able to wake up. If it turns on after a long charge, I'll report back if I figure out which module it needs.

[Renate]

I'm so confused even though I tried to figure out how Apple takes a standard and suddenly makes it "Apple" that it won't work normally.
I have made the hardware and software for HID devices for USB and Bluetooth.

[akadaedalus]

Originally Posted by sios00

I thought maybe I would need to build more .ko files for the kernel, based on this link https://github.com/tylpk1216/kobo-libra2-uhid-module, but I can't seem to be able to insmod any of the .ko files I have built on my own. The uhid.ko file from the GitHub link can be insmod though.

I am using Ubuntu WSL on Windows to do the building.

This is what happens if I try to load a .ko file that I have built:

[root@kobo kobo-libra2-uhid-module]# insmod uhid.ko
insmod: can't insert 'uhid.ko': invalid module format
[root@kobo kobo-libra2-uhid-module]#

What do you get when you do "file uhid.ko"? You may have not ended up with the ARM format. Also I have found that you need to build as much of the whole kernel as possible before building the individual module.

I've uploaded some evtest output for the various buttons, sorry it's an image as I had to boot Ubuntu from USB in order for the Bluetooth Beauty-R1 to be detected (VM didn't work!)

What you might try to do is run "lsmod" before you connect the device in Linux, then "lsmod" afterward. It may give you a clue on what module you need. That's how I figured out I needed hid-apple. Apple-style keyboards may be pretty common for iOS shutters.

[akadaedalus]

Originally Posted by Renate

I'm so confused even though I tried to figure out how Apple takes a standard and suddenly makes it "Apple" that it won't work normally.
I have made the hardware and software for HID devices for USB and Bluetooth.

I know. I feel dirty for having an Apple device in my home and even compiling code for it.

(I exaggerate. My work-provided phone is iOS.)

[Quoth]

Originally Posted by Renate

I'm so confused even though I tried to figure out how Apple takes a standard and suddenly makes it "Apple" that it won't work normally.
I have made the hardware and software for HID devices for USB and Bluetooth.

They took the 3.5mm 4 pole jack standard and changed it so that sleeve (and thus a metal cover) was mic instead of "earth"/OV/"return".

They did their own version of USB charging, so only (back then) an Apple PSU would fast charge, other 1A or more chargers only charged at 0.5A.

They increased the current possible to twice the USB standard (then) on a port so a power hungry CD or DVD drive would work (I forget which).

Though with OS9 to OS X change the OS went from proprietary to based on BSD (from NextStep) in about 2001 or 2002, the file system is still proprietary.

A real USB or BT keyboard isn't one kind of device. Apple, Android and ChromeOS are technically different from windows/everything else. It's more than the language map layout. HID was mainly for mouse, keyboard, tracker ball, touchpad and joystick on USB, and it's the totally worst USB for security. A malicious "mouse" or keyboard can silently inject a script. Android had to change how USB worked for security to avoid malicious chargers, hence later Android versions pop-up a dialogue, though might still be vulnerable.

It's no surprise.

EDIT:
And ironically after messing up the 4 pole 3.5mm jack spec for audio, they now don't even fit them. There is still the DAC/ADC for mic and speaker (though they now use the awful MEMS microphone, so the ADC might not be accessible). Saves about 30c.

[akadaedalus]

Update: My 5-button ring is basically DOA. It can "charge" with a red LED but won't turn on. It's labeled JX-05 and I chucked it in the trash.

I figured I'd give the "Beauty-R1" device a try but most of it functions essentially as a mouse and is useless unless you want to long-press it, long-time, then two or three of the six buttons kind of work. I'm returning it to Amazon.

I also gave in and bought an 8bitdo Micro. I didn't really want to because it's too twee, but I actually have been looking for a small, cost-effective macro pad for various purposes. Why not basic black though... I'll see if I can come up with some extended uses in the Kobo. The keyboard mapping thing does just work though, if somewhat limited.

[Renate]

Originally Posted by Quoth

A real USB or BT keyboard isn't one kind of device.

I looked into this a bit.
Apparently the Apple "aluminum" keyboard is a standard HID over GATT keyboard but in a slightly non-standard report format.
This only allows it to say, "I'm different" without bringing any features.
Theoretically, I believe a normal Android or whatever should be able to read it without problems.
But apparently the HID driver is so tied to the "standard" form.

If somebody has the Apple keyboard I wouldn't mind seeing it try to connect to an Android or even a Kobo.
System > Developer options > Enable Bluetooth HCI snoop log.
(You have to restart after enabling it and after disabling it.)
I'm not sure how BT snooping works on Kobo.

[akadaedalus]

Regarding additional options beyond prevPage and nextPage.

I spent an inordinate amount of time looking at the btpt source code and decompiling the libnickel library. I don't code Qt so it was a big headache but I could at least make some guesses. a) it only uses ReadingView methods, b) the method needs to take zero arguments, and c) it somehow truncates the method name to about 12 characters when trying to call them. prevPage() and nextPage() are callable with btpt but most/all others aren't. goToPrevChapter() even requires an argument so unless it didn't at one time, it was never a valid option at least on the Libra 2. prevChapter() does exist in the AudiobookPlayer methods and that is probably where the confusion came from.

To make the fancier remotes like the 8bitdo work, it would probably require a new plugin that calls more than just ReadingView stuff. I have a notion of maybe hooking into NickelMenu/NickelDBus with an event listener similar to btpt but honestly I don't think I'll have the time to look into that this year at all. Remember I don't code Qt and it would be a huge time suck.

[akadaedalus]

Originally Posted by Renate

Try hooking up a BT keyboard or USB OTG keyboard and trying all the F1-12 keys to see if they do anything. Don't forget Shift, Ctrl and Alt.

Did this. There is literally nothing mapped on the LIbra 2 other than esc, home, and arrow keys. The tab did seem to do some kind of refresh activity but I couldn't tell what it was.

[Quoth]

Originally Posted by Renate

…
Apparently the Apple "aluminum" keyboard is a standard HID over GATT keyboard but in a slightly non-standard report format.
This only allows it to say, "I'm different" without bringing any features.

…

Somehow I'm not surprised. It is probably also is x3 to x10 retail price of a Cherry.

[blacksheepwall]

Originally Posted by NoGoNearKobo

Could you confirm which device you were able to get the D01 Pro ring working with? There are many users struggling to use the popular 'tiktok' ring with the Libra 2.

I managed to get the D01 Pro ring to work with my Kobo Libra2 and provided a ready to use solution https://github.com/Lifeisawful/kobo-...ro-page-turner

[Fahrenheit451]

“AB Shutter3” bluetooth remote camera shutter release controller as Kobo Libra 2 page turner.

“Camera 360/IOS” button on “AB Shutter3" device triggers KEY_VOLUMEUP event, while “android” - KEY_VOLUMEDOWN. This is different from other similar devices, for example
https://www.mobileread.com/forums/sh...&postcount=193
,
https://dev.to/wincentbalin/key-code...shutter-3-2n0h .

I installed UHID kernel module (https://www.mobileread.com/forums/sh...d.php?t=352280) on my Kobo Libra 2 and with
kobo-btpt configuration file “AB Shutter3”:

prevPage EV_KEY KEY_VOLUMEDOWN 1
nextPage EV_KEY KEY_VOLUMEUP 1

can turn pages in both directions.

Adding some electrical tape between buttons and the housing makes the “keyboard” a bit THOCKier .
Some packaging foam between PCB and the housing further reduces clicky sound - great for reading at night.

The remote was recently purchased on Aliexpress (~2$, Elbert Store). The only IC on the PCB has no label.

[Renate]

I dove deep into that "AB Shutter" once.
I'm pretty sure that one of those keys actually generates two separate key presses in succession.

[Tintenfisch]

Edit, because I solved it!
I accidentally put the Zero 2 in the wrong mode (pressed START + R-button, instead of START + X-button). Now with Start + X-Button it works fine and turns pages flawlessly!
Such a nice comfort to turn pages without having to hold the device!