Re: About TRB_TO_EP_INDEX() macro using

From: gregkh@xxxxxxxxxxxxxxxxxxx
Date: Mon Aug 05 2013 - 04:33:37 EST

On Mon, Aug 05, 2013 at 08:07:25AM +0000, Du, ChangbinX wrote:
> 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()

Care to send a patch showing how you would change this if it is


greg k-h
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