* Arnd Bergmann <arnd@xxxxxxxx> [230112 14:31]: > On Thu, Jan 12, 2023, at 15:05, Aaro Koskinen wrote: > > On Thu, Jan 12, 2023 at 11:19:53AM +0100, Arnd Bergmann wrote: > >> On Thu, Jan 12, 2023, at 10:53, Tony Lindgren wrote: > >> > >> So if we want to kill off the old DMA stuff there is actually > >> a choice between either making omap_udc PIO-only or converting > >> it to use the standard dmaengine interface. > > > > I use this driver on Palm TE and 770, and without it those boards would > > be useless for my use cases. Also DMA doubles the throughput, probably > > also power usage is smaller. > > Ok, if the performance is important, converting to dmaengine > is probably best. Do you know if this is just a straightforward > replacement of the function calls, or are there technical reasons > why it's not using the dmaengine interface yet? Yes I agree dmaengine is the best solution. Seems like this is the last driver using the old api that never got updated probably because it's not used on the newer SoCs. I don't think there are any technical reasons to not use dmaengine here. FYI, the last blocker for dmaengine use was for drivers using port_window that got added with the drivers/usb/musb/tusb6010_omap.c dmaengine conversion a few years back. Regards, Tony