Hello, On 14.05.2019 21:29, Fredrik Noring wrote: > Thanks Robin! > >>> For HCs that have local memory, replace the current DMA API usage >>> with a genalloc generic allocator to manage the mappings for these >>> devices. >>> This is in preparation for dropping the existing "coherent" dma >>> mem declaration APIs. Current implementation was relying on a short >>> circuit in the DMA API that in the end, was acting as an allocator >>> for these type of devices. >>> >>> Only compiled tested, so any volunteers willing to test are most welcome. >> >> I recall an out-of-tree PlayStation 2 OHCI driver being another >> HCD_LOCAL_MEM user - if Fredrik and Juergen are still active on that, >> hopefully they might be able to comment on whether this approach can >> work for them too. Patchwork link just in case: >> https://patchwork.kernel.org/project/linux-usb/list/?series=117433 > > True. In fact I'm preparing a patch submission for this PS2 OHCI driver, > along with about a hundred other patches (unrelated to the USB subsystem). > Hopefully in a few weeks. My patches are currently on top of v5.0. What > branch/version is recommended to try this DMA update? I think that any recent kernel will do, so I'd say your current branch should be fine. > Here is the v5.0.11 PS2 OHCI driver, for reference: > > https://github.com/frno7/linux/blob/ps2-v5.0.11/drivers/usb/host/ohci-ps2.c Please note that the driver will need to be updated, see here for an example: https://patchwork.kernel.org/patch/10943105/ --- Best Regards, Lauretniu
