On Thu, 16 Jul 2020 23:15:16 +0200, Olivia Mackintosh wrote:
Hello,
I am trying to add a device quirk for the Pioneer DJM-750 mixer. I have attached a patch to illustrate what I'm trying to achieve. It is nearly identical to https://patchwork.kernel.org/patch/11521019/ except for the differences in channels. I have verified the settings against valid USB transfers.
While observing behaviour with a Windows 10 VM, the 8 pieces of data appear to be 8 isochronous packets within a single frame as opposed to 8 microframes (each with their own transfer). Should this have any impact on the ability for the device to function? If so, is there a setting I am missing to account for this? Or, am I simply clutching at straws and completely on the wrong path.
It's rather a generic USB-audio issue, not specific to your device, about how to set up URBs. This influences on the performance, yes; it defines stability vs latency. On Linux driver, the condition varies depending on the hw_params.
This is rather device specific so I would not expect anyone to help troubleshoot this specific device but what I suspect is the problem is the way the audio data is arranged in the transfer.
Any suggestions and pointers on how to proceed are very much appreciated.
So did you see any actual problem with your patch?
thanks,
Takashi