[U-Boot-Users] PXA27x usbtty start up sequence

Rodolfo Giometti giometti at enneenne.com
Sun May 20 18:07:02 CEST 2007

On Sun, May 20, 2007 at 02:54:36PM +0100, Bryan O'Donoghue wrote:

> That's really quite odd. The following should be similar to what you
> did and it *does* seem to work just fine, for me.

I find the problem.

It's into usbtty_poll() which calls write_buffer() when the USB device
get connected (usbtty_configured() is true).

Function write_buffer() calls udc_endpoint_write() who calls driver
low level function. This low level function, PXA270 specific, waits
all data has been transmitted before returning to the caller, this
because I need to know when a packet has been transmetted before
sending a new one or I get some data lost during transmission.

When I connect kermit/minicom to /dev/USB0 the UDC sends stdout data
and everything works well...

How I can resolve the problem? Maybe using a timeout during




GNU/Linux Solutions                  e-mail:    giometti at enneenne.com
Linux Device Driver                             giometti at gnudd.com
Embedded Systems                     		giometti at linux.it
UNIX programming                     phone:     +39 349 2432127

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