Hi everybody, I'm trying to maximize USB throughput when transferring data from an OMAP3430 device (MUSB OTG controller) to an EHCI host using isochronous transfers. Using a 1024 byte maximum packet size in single buffered mode, I can reach a bandwidth of around 4 MB/s. This is around half of the maximum theoretical bandwidth for high-speed, non high-bandwidth isochronous transfers, which sounds pretty normal in single buffered mode. In order to raise the throughput I've configured the MUSB endpoint buffer in double buffered mode (BUF_DOUBLE). The throughput went up to nearly 7 MB/s, but transfers became much more unreliable. More packets are lost, and the transfer even freezes completely from time to time (although this is sometimes difficult to reproduce). I have no USB analyzer so I'm not sure what really happens on the bus. Is there any known reliability issue with MUSB double buffered endpoints ? -- Regards, Laurent Pinchart -- 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
