I wholeheartedly agree with everything you wrote, Mike. Takashi is the person who knows best how to implement these changes, and is definitely the most capable. I will get back to you about retesting my other Roland devices with this trick, although I only have a few of the many devices I'd ultimately like this solution implemented for. Also, I haven't noticed the sync-related clicking with the other devices I own, but I'm confident they won't be hurt by the change. I'll let you both know, though, when I get around to testing them. Thanks as ever, Lucas On Fri, Apr 9, 2021 at 11:47 AM Mike Oliphant <oliphant@xxxxxxxxxxxx> wrote: > Hi Lucas, > > Your observation that the Roland D-05 still needs the capture feedback > made me try some more testing, and I think the GT-1 actually is the same. > > I use my device with jackd running for both capture/playback at the same > time. This works for me without capture feedback enabled. But, it turns out > that just doing an "arecord" without playback fails. Enabling the capture > feedback makes capture also work without playback (and everything else > still works perfectly). > > Given this, I agree that it seems likely that most, if not all, of these > Roland devices work the same way. It would be great to get more devices > tested, though. > > As to an actual patch, I think it is probably best left to Takashi to > decide if he is comfortable with making a change to > snd_usb_endpoint_start() in endpoint.c, and if so, how he wants to make it > conditional for devices - whether an ID check in endpoint.c, or a flag on > feedback setup, or some other way. > > Mike >
