[U-Boot] [PATCH V4 03/17] usb: gadget: ether set wMaxPacketSize

Marek Vasut marex at denx.de
Mon Sep 23 02:04:07 CEST 2013


Dear Troy Kisky,

> On 9/20/2013 3:52 AM, Marek Vasut wrote:
> > Dear Troy Kisky,
> > 
> >> set wMaxPacketSize for full speed descriptors
> >> fs_source_desc, fs_sink_desc to 64.
> >> 
> >> Full-speed bulk endpoint can have a maximum packet size of
> >> 8, 16, 32, or 64 bytes, so choice 64.
> >> 
> >> The hs_source_desc, hs_sink_desc, already have their wMaxPacketSize
> >> set to 512. That is the only legal value for high speed bulk endpoints.
> >> 
> >> Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
> > 
> > Why do we need this patch? What issue does this fix ?
> > 
> > Best regards,
> > Marek Vasut
> 
> I could try full speed mode without this and see how linux behaves when
> given bad data,
> but that would not says anything about other O.S.es. It seems safer just
> not to give out
> bad data.

Certainly. Will this not cause issues with the MPC8xx controller and OMAP1510 
controller?

Best regards,
Marek Vasut


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