On Mon, 15 Oct 2007, Dirk Jagdmann wrote:

> Hello usb experts,
> 
> I want to develop a filter for a card reader, that is connected via a 
> FTDI usb-serial converter to the host computer. The filter will be a 
> standard linux machine that should be placed in the middle of an 
> existing setup. Two pictures will clarify this:
> 
> Current Setup:
> 
> +--------------+ usb +--------+
> |Reader w/ FTDI|-----|Computer|
> +--------------+     +--------+
> 
> Future Setup:
> 
> +--------------+ usb +------------+ usb +--------+
> |Reader w/ FTDI|-----|linux filter|-----|Computer|
> +--------------+     +------------+     +--------+
> 
> Interfacing the reader from the linux box works without problems. It is 
> mapped to one of the /dev/ttyUSBx devices.
> 
> But I don't know where to start on the other side of the linux box? 
> Would I need to develop a kernel driver, or could this be done with a 
> userspace driver? As the "computer" accesses the reader with standard 
> serial semantics the device emulated by the linux box must not be a 
> FTDI, any device recognized as usb-serial will suffice. So maybe someone 
> has already done something similar and there is a software I could use 
> as a start.

Look at

        http://www.linux-usb.org/gadget/

You want to use the serial gadget.  Your "linux filter" will have to 
have special hardware in order to appear as a USB device to the 
"Computer".

Alan Stern


-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/
_______________________________________________
Linux-usb-users@lists.sourceforge.net
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-users

Reply via email to