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

Troy Kisky
2013-09-23T19:51:02Z

On 9/22/2013 5:04 PM, Marek Vasut wrote:
> 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@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
>
Good point. ether.c is compiled when CONFIG_USB_ETHER is set.
And omap1510_udc.c, mpc8xx_udc.c will only be compiled when
CONFIG_USB_ETHER is NOT set.

So, not a issue at present. I doubt anyone will upgrade these old boards
to support CONFIG_USB_ETHER.

Thanks
Troy