Hi, all, We are testing the USB Host controller from Xilinx using a PowerPC platform. This test is FS isochronous OUT, with the maxp 1023 and interval 1ms. We noticed that with direct connection between the host controller and the FS iso OUT device, the s-mask is 0x3f. And the test finished fine. However, if the device is connected through a FS hub, then the sitd s-mask becomes 0x1f8, this makes the 6th packet crosses the frame boundary. From EHCI spec page 104, section 4.12.3.1, it says under Case 2a: Software must never schedule full-speed isochronous OUTs across an H-Frame boundary. The test therefore failed, because the host controller never put the 6th packet out. The kernel version is 2.6.30. The function sitd_slot_ok() shifts the s-mask by the starting frame number. It does check for crossing frame boundary for IN case, but never does anything for OUT. I wonder whether it is a bug? Or, it is intended? Thanks, Julie. This email and any attachments are intended for the sole use of the named recipient(s) and contain(s) confidential information that may be proprietary, privileged or copyrighted under applicable law. If you are not the intended recipient, do not read, copy, or forward this email message or any attachments. Delete this email message and any attachments immediately. -- 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
