I flashed p7300's recovery by mistake.
No download mode
No recovery mode
Adb cant find device.
Odin is also cant find device.
This is Samsung galaxy tab 8.9 tablet forum [P7300 & P7310 & P7320 & SGH-I957],
so your question is in the wrong forum, although I can answer your question
Unfortunately in your situation, you can't do anything to fix it, all you can do is:
take it to a near Samsung store, so that they can fix it for you [they need to disassemble your device to fix it]
I had the same situation couple of months ago, and fortunately the device's warranty was still valid, so they fixed it without paying a penny