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 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html