Re: [Ftdi-usb-sio-devel] howto: setting up driver to ftdi usb

[Bill R. <br...@pa...>]

Mike Rosing wrote:

>On Thu, 14 Nov 2002, Bill Ryder wrote:
>
>  
>
>>As far as I know the device is not supported in the 2.2 kernels - just
>>the 2.4 kernels.
>>    
>>
>
>Bummer.  It said on the kernel page that 2.2.20 has the driver (which
>is obvious since it sees the device).
>

Does it write into /var/log/messages saying a FTDI device was detected? 
/proc doesn't tell the whole story - it will take you a usb device was 
detected.

>>It is possible that the usb-serial default driver is picking up the
>>device but there is no way that will work properly.
>>
>>So you'll need to move to a 2.4.18 kernel or above.
>>    
>>
>
>Any particular reason why? 
>
The main reason the device is 'not supported' in the 2.2 kernels is 
because I don't run the 2.2.x kernels :-)

 I am making an *assumption* (possibly unwarranted) that it won't work 
because I am not aware of anyone backporting the current drivers - and 
the early versions had plenty of bugs and they only supported the 
original SIO.

> I've got the sources, maybe I can hack
>something and fix my problem?  When I do a write() to the /dev/ttyUSB0,
>which routine in ftdi_sio.c actually gets it?
>
ftdi_sio_write

The trick with the devices is the original device (the SIO)  required a 
byte count on the front of the output packet, the newer devices (ie the 
232AM and 232BM, 245 don't.

So your choices are to backport the current driver, or compare the 
current driver to the driver in 2.2 and fix it manually. Certainly not 
impossible.


Good luck!

Bill