Re: [v4] usb: UHCI: fix pkt size in TD for a sg element

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On 06/24/2013 05:46 PM, Felipe Balbi wrote:
>> The DMA engines (intern or extern) do not merge transfers. Some 
>> of them are clever enough to transfer a single 1024 as two 512 
>> requests. But two 256 bytes requests are not merged into one 512 
>> request. I believe the device side of dwc3 is able to do so if 
>> marked properly but musb host side won't be able to do so.
> 
> right, that's why we use a temporary buffer to copy data to and do 
> the transfer.

I remember this is done on dwc3's gadget RX side because the dma engine
expects a multiple of max packet size. You do this on musb as well?

Sebastian
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