On Mon, 4 Feb 2013, victor yeo wrote:
> Thanks, i made a big progress. The udc driver is able to pass the ep1
> data (CBW) to gadget driver, and gadget driver handles the data (which
> is SCSI Inquiry command), and udc driver is able to send out the reply
> and CSW to host.
>
> After that, in get_next_command(), in the statement below, the
> bh->state is 2 (BUF_STATE_BUSY), and the get_next_command() goes to
> sleep and never wakes up.
>
> while (bh->state != BUF_STATE_EMPTY) {
> rc = sleep_thread(fsg);
> if (rc)
> return rc;
> }
>
> How to set "bh->state" to BUF_STATE_EMPTY after the buffer is processed?
It gets set to BUF_STATE_EMPTY in several different places, depending
on the purpose the buffer was used for. See bulk_in_complete (your UDC
driver should call this routine for every request over a bulk-IN
endpoint, when it is safe for the gadget driver to overwrite the data
in the transfer buffer and re-use the request). See also
get_next_command, the line just after the call to received_cbw.
You know, you didn't have to ask me this question. You could have
found the answer more easily yourself simply by searching for
BUF_STATE_EMPTY in file_storage.c.
Alan Stern
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