RE: [PATCH] usb: optimize set_bulk_out_req_length() in mass storage gadgets

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> From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx] 
> Sent: Tuesday, October 04, 2011 6:57 AM
> 
> On Mon, 3 Oct 2011, Paul Zimmerman wrote:
> 
> > Since bulk max packet size must always be a power of 2, we can
> > use the 'and' operator instead of modulus.
> 
> Just a quick observation: AFAIK, in wireless USB the bulk maxpacket
> size does not have to be a power of 2.  On the other hand, if it isn't
> then it's not clear that the mass-storage gadgets would work.

Drat, I forgot about WUSB and it's dreaded non-power-of-2 max packet
sizes.

I guess it's better not to apply the patch then, it's probably only
a tiny optimization on any halfway modern CPU.

-- 
Paul
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