To enable SSH:
- Flash developer firmware from web gui, for example this: http://bigota.miwifi.com/xiaoqiang/rom/r3g/miwifi_r3g_firmware_c2175_2.25.122.bin
- Bind your router to your xiaomi account via Mi Wi-Fi app (android: https://play.google.com/store/apps/details?id=com.xiaomi.router)
- Go to this page (pay attention to the URL, it must be HTTPS not HTTP, change it manually if it revert to HTTP): https://d.miwifi.com/rom/ssh
- Login with your account
- Click on "下载工具包" button to obtain your unlock file, take note of your SSH password
- Rename the file to miwifi_ssh.bin
- Put it in your usb flashdisk (must be MBR and FAT32)
- Power off your router
- Plug in the flashdisk
- Press and hold the reset button
- Power on your router (while holding the reset button)
- The router's will flash LED with flash orange, release the reset button when it is flashing rapidly (and you see activity led flashing on your flashdisk if it has one)
- Wait until the LED turns blue
- The router will reboot and you can login to SSH shell with root and the provided password
And then you can proceed to flash LEDE...