How can I use DMA for the USB host controller driver of smxUSBH?
For OHCI, UHCI and EHCI, the DMA transfer is transparent to the host controller driver so you do not need any special code. For ISP116X, ISP1362, and ISP1761, you can use DMA to transfer data from processor’s memory to the chip but we have not implemented it because DMA operation is processor-dependent. However you can implement it yourself in the porting layer functions, without the need to know the details of that host controller. For those host controller drivers, we define the data transfer function su_ISPxxxReadBuf() and su_ISPxxxWriteBuf() in the porting layer. What you need to do is to implement those functions to use DMA instead of the default PIO approach.
