[Cbe-oss-dev] [PATCH 2/5] usb: PS3 EHCI HC NAK work-around

[Alan Stern]

On Thu, 17 Nov 2011, Geoff Levand wrote:

> On Tue, 2011-11-15 at 11:52 -0500, Alan Stern wrote:
> > On Tue, 15 Nov 2011, Geoff Levand wrote:
> > 
> > > PS3 EHCI HC errata fix 236 - During high speed bulk out and high speed control
> > > out transfers the PS3 EHCI HC will issue an OUT token on the USB bus when a
> > > device responds with a NAK.  The USB 2.0 standard specifies that a PING token
> > > must be output.  The work-around is for the HC driver to initialize the
> > > RL (NAK count reload) field of the queue head to a non-zero value.
> > 
> > This can't be right.  The RL field is already initialized to 
> > EHCI_TUNE_RL_HS, which is #defined as 4.
> 
> Yes, you are correct, I must have missed that.
> 
> > Maybe for PS3 EHCI you want to #define it as 2 instead.
> 
> The errata sheet says 'using the RL of the QH with values
> other than 0', so 4 should be OK.

So we can drop this patch, right?  Have you ever encountered the 
problem it was supposed to fix?

Alan Stern