tylpk1216 / kobo-libra2-uhid-module

Insert this module to support some bluetooth pageturners on Kobo Libra 2.

kobo-libra2-uhid-module

My Logitech R500 can't work on Kobo Libra 2 so I try to check the problem. Finally, I rebuild the uhid.ko and it works with R500.

Because Kobo Clare 2E has the same issue of bluetooth, you could use this project concept to support your bluetooth device. I use kobo-libra2-uhid-module to use my Logitech R500 on Kobo Clare 2E.

How to use it

For version 4.31.19086

1. Install NickelMenu, I use it to launch the application.
2. Insert the device into your PC over USB.
3. Put kobo-libra2-uhid-module folder in ".adds" folder of device.
4. Copy "kobo-libra2-uhid-module/config" to ".adds/nm" or you could add the text below to your own config if you already use NickelMenu.

menu_item :main    :Bluetooth Patch (toggle) :cmd_output         :500:quiet :rmmod -w /mnt/onboard/.adds/kobo-libra2-uhid-module/uhid.ko
  chain_success:skip:3
  chain_failure                              :cmd_spawn          :quiet :exec /mnt/onboard/.adds/kobo-libra2-uhid-module/run.sh
  chain_success                              :dbg_toast          :insmod uhid.ko successfully
  chain_always:skip:-1
  chain_success                              :dbg_toast          :rmod -w uhid.ko successfully

How to build kernel

I follow the concept of this site. However, I use WSL(Widows Subsystem for Linux) to build the uhid.ko. If your WSL miss some applications, you could use apt command to install them.

sudo apt install xxx

Here is my steps.

1. Use NickelMenu to telnet into the device to get the /proc/config.gz. The user name is root, and the password is empty.

menu_item :main    :Telnet (toggle)          :cmd_output         :500:quiet :/usr/bin/pkill -f "^/usr/bin/tcpsvd -E 0.0.0.0 1023"
  chain_success:skip:5
  chain_failure                              :cmd_spawn          :quiet :/bin/mount -t devpts | /bin/grep -q /dev/pts || { /bin/mkdir -p /dev/pts && /bin/mount -t devpts devpts /dev/pts; }
  chain_success                              :cmd_spawn          :quiet :exec /usr/bin/tcpsvd -E 0.0.0.0 1023 /usr/sbin/telnetd -i -l /bin/login
  chain_success                              :dbg_toast          :Started Telnet server on port 1023
  chain_failure                              :dbg_toast          :Error starting Telnet server on port 1023
  chain_always:skip:-1
  chain_success                              :dbg_toast          :Stopped Telnet server on port 1023

2. Copy /proc/config.gz to your device drive, then use PC to get the file.

cp /proc/config.gz /mnt/onboard

3. Download kernel from here. I download linux-4.1.15.tar.gz.
4. Download cross compiler from here. I download gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabihf.tar.xz.
5. Suppose your work dir is /mnt/d. copy relevant files to this folder and cd to this folder.
6. Extract config.gz

sudo gunzip config.gz

7. Extract linux-4.1.15.tar.gz

sudo tar zxvf linux-4.1.15.tar.gz

8. Extract gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabihf.tar.xz

sudo tar Jxvf gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabihf.tar.xz

9. Enter linux-4.1.15 folder.

cd linux-4.1.15

10. Copy config to this folder.

cp ../config .config

11. Modify .config file, add CONFIG_UHID=m to this file.

CONFIG_UHID=m

12. Run make command to set up configuration from old settings.

sudo make ARCH=arm CROSS_COMPILE=/mnt/d/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabihf/bin/arm-linux-gnueabihf- oldconfig

13. Run make command to build the uhid.ko. If you have error when doing insmod. Please make all kernel first.

sudo make ARCH=arm CROSS_COMPILE=/mnt/d/gcc-linaro-4.9.4-2017.01-x86_64_arm-linux-gnueabihf/bin/arm-linux-gnueabihf- drivers/hid/uhid.ko

14. After completing building, the uhid.ko is in drivers/hid folder. You colud use file command to check whether this module is for ARM or not.

file drivers/hid/uhid.ko