Dne 26. 11. 20 v 14:16 Jerome Brunet napsal(a):
Maximum data rates that I used were (AFAIR) 8 channel 192kHz/32bit, but there is another issue with high data rate if someone uses so many channels, very high sampling frequency or sample size that data can't fit into allowed (by USB spec) max packet size of endpoint. In this case need to decrease bInterval of endpoint.
Should anyone test the patches with RPi4 dwc2 as the gadget, please note the recently accepted patch https://patchwork.kernel.org/project/linux-usb/patch/e9e7d070-593c-122f-3a5c-2435bb147ab2@xxxxxxxxxxx/ which allows using full 1024 bytes maxpacketsize on EP OUT. It is not an enumeration issue, but the old (= existing) RX FIFO size drops data with packet sizes above 960 bytes.
Thanks a lot for the great work. Best regards, Pavel.