Re: [Qemu-devel] Hi Natalia.. A query regarding QEMU

[Natalia Portillo]

Hi Ankit,

El 03/11/2011, a las 20:37, Ankit Verma escribió:

> Hi Natalia,
> 
> I am trying to support usb connections on Android Emulator. Since
> Android Emulator is based on QEMU, i thought you could give some
> insight on how to enable usb connections for android emulator.
> 
> As per the following information in google's android website -
> http://developer.android.com/guide/developing/devices/emulator.html
> 
> Emulator Limitations
> 
> In this release, the limitations of the emulator include:
> 
>>>> No support for USB connections
> No support for Bluetooth
> 
> Can you give some insight.

First of all, while Android Emulator is based on QEMU, they have made their own 
modifications, that have not been sent to us, so it's not 100% QEMU.

What I can tell you is that Android phones/tablets are USB devices, and QEMU 
have an incomplete support for REAL USB devices with QEMU behaving as an USB 
host. But QEMU is not designed currently to work as a USB device to a real USB 
host.

If you want to code that support yourself, you'll need a virtual host 
controller implementation on the host operating system, and then implementing 
QEMU behavior as an Android device (be it USB Mass Storage Device or Android 
Debug device).

For the first part, there are some implementations, called USB-IP, that create 
a virtual host controller both on Windows and on Linux hosts, and both are 
incomplete as I write.
For the second part that has never been tried (afaik) and would be mostly 
dependent on what solution you chose for the first part (as there will never be 
a way for QEMU to talk to a real host controller as a device).

I hope this gives insight for you, and any other question I may be of help, 
feel free to ask.

BTW, I'm CCing this to the mailing list, as other people may find this 
interesting, want to contribute with their opinions, so on.

Regards,
Natalia Portillo