Hi all:
I have some questions about usb driver:
1. what is qh->stamp used for?
I trace the source and I found it seems only used to increase the
performance such that we will avoid re-scan the previous qh.
But if we don't check qh->stamp, in qh_completions, it will return
immediately if the qh has been scanned before, since the qtd_list of
the qh is empty, right.
if so, why we still need to check qh->stamp?
Meanwhile, there will be 1/8192 chance that 2 stamps be the same,
suppose my frame list size is 1024, right?
2. what is the max value of "Frame index register"
I set my frame list size as 1024, in my opinion the max value of
"Frame index register" should be 8192, 0x2000.
But I found sometimes it will over 0x2000.
Does that I calculate the wrong value?
--
Regards,
miloody
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
