USB, select/poll for ucom
danny at cs.huji.ac.il
Fri Jun 27 07:58:10 PDT 2003
> I thought that ucom does do that. It uses ttypoll as its polling
> function, and seems to insert data into the tty structure on an
> interrupt basis. That is hidden a little bit by the usb driver
> structure. In the middle of ucomopen we call ucomstartread which
> posts a read onto the bulk in pipe. This read fires a callback when
> it is 'finished' which the processes the data. So I think that maybe
> that transfer is never completing.
some more reading, and it seems that indeed open fires up a startread,
so that select should work. In my case, i just went the old fashion way,
sigalarm/read, but it seems that nothing is being read by the driver :-(
assuming that uco/ulpcom works - the problem must be in the way this
smartcard reader works.
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