hi all:
when I trace linux ehci driver source code.
I have some questions
1. in itd_slot_ok, why we have to
uframe %= period;
and use this uframe to calculate the bandwidth?
suppose start passed to itd_slot_ok is 537, period, usb->interval, is 8.
that mean we want to know whether bandwidth of microframe 537 is enough.
Not want to know whether 537%8 =1
the bandwidth of microframe 1 is enough.
2. Below is part of message excerpted from usb mon log:
db1e2000 81051026 S Zi:1:002:6 -115:8:5327 1 -18:0:132 132 <
db1e2000 81058043 C Zi:1:002:6 0:8:5391:0 1 0:0:4 132 = 2efd82fd
0cfeffff 84feb3ff 98fec4fb 08ffdaf8 060059fb 8b01d2ff db02de01
why these 2 ep->start_frame are different, 5327 in "-115:8:5327" and
5391 in "0:8:5391:0"?
The log is captured with the same urb, for submitting and completing.
That mean ep->start_frame=urb->start_frame in submit and complete
should be the same, right?
appreciate your help in advance,
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