About TRB_TO_EP_INDEX() macro using

From: Du, ChangbinX
Date: Mon Aug 05 2013 - 04:07:37 EST


Recently when I check xHCI code, find that some functions try to get EP index
from a Command Completion Event TRB via TRB_TO_EP_INDEX() macro.

This is totally wrong. The macro definition is:

#define TRB_TO_EP_INDEX(p) ((((p) & (0x1f << 16)) >> 16) - 1)

TRB_TO_EP_INDEX only applies to Transfer Event TRB. But for Command
Completion Event TRB, there is no Endpoint ID field. So, we cannot directly
get EP index from these TRBs, but we can find it by the TRB Pointer.

Here list two functions for you to check:
handle_stopped_endpoint()
handle_reset_ep_completion()

Regards & Thanks!
Changbin


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