Re: [patch 11/12] usb: musb: adding high bandwidth support

[David Brownell <david-b-yBeKhBN/0LDR7s880joybQ@public.gmane.org>]

On Wednesday 18 February 2009, greg-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org wrote:
> From: Ajay Kumar Gupta <ajay.gupta-l0cyMroinI0@public.gmane.org>
> 
> Tested with Creative (Live! Cam Optia) USB camera which uses
> high bandwidth isochronous interface.FIFO table has been updated
> for Rx high bandwidth case.
> 
> Signed-off-by: Ajay Kumar Gupta <ajay.gupta-l0cyMroinI0@public.gmane.org>
> Cc: Felipe Balbi <felipe.balbi-xNZwKgViW5gAvxtiuMwx3w@public.gmane.org>
> Cc: David Brownell <dbrownell-Rn4VEauK+AKRv+LV9MX5uipxlwaOVQ5f@public.gmane.org>

NAK on this one ... Ajay, please re-issue with udpates
to verify that the silicon supports high bandwith ISO!

There's code in musb_core_init():

        if (reg & MUSB_CONFIGDATA_HBRXE) {
                strcat(aInfo, ", HB-ISO Rx");
                strcat(aInfo, " (X)");          /* no driver support */
        }
        if (reg & MUSB_CONFIGDATA_HBTXE) {
                strcat(aInfo, ", HB-ISO Tx");
                strcat(aInfo, " (X)");          /* no driver support */
        }

What it needs to do is save a flag instead of
printing the " (X)" ... and test that flag later,
instead of assuming it's set.

Examples:

 - DaVinci DM6446 and DM355 don't support high bandwidth
   for either RX or TX.

 - Neither does TUSB6010 (and presumably TUSB6020), which
   was sort of extracted from the DM6446 (adding more RAM,
   splitting out the fibula and tibula chips, etc)

 - OMAP3 ES2.1 and ES3.1 support it for RX and TX ... but
   the ES3.0 chips only support it for RX (goofage?)

I don't know what the Blackfin or ST-Micro parts do, but
one shouldn't assume they always support it either.

Also, I suspect you should probably create a new fifo_mode
table to support this.  These changes will break some
composite gadget code I've seen ... and I'm curious why
you didn't just configure that endpoint in shared-FIFO mode,
so that it'd support both RX and TX in high bandwidth.

- Dave
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