Sergei, Another option is to have the cppi-generic code reside in the musb directory itself. We do not have other peripherals such as Ethernet using cppi4.1 infrastructure in the near future. Given this I think it will be better to locate this code in the "drivers/usb/musb" directory itself and decide on any relocation later if the need arises (which I feel is remote). regards swami ________________________________________ From: Sergei Shtylyov [sshtylyov@xxxxxxxxxxxxx] Sent: Friday, November 27, 2009 1:00 AM To: Russell King - ARM Linux Cc: Gupta, Ajay Kumar; Hilman, Kevin; davinci-linux-open-source@xxxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; david-b@xxxxxxxxxxx; stanley.miao; Subbrathnam, Swaminathan; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; dan.j.williams@xxxxxxxxx; maciej.sosnowski@xxxxxxxxx Subject: Re: [PATCH RFC 1/2] MUSB: CPPI 4.1 DMA driver (take 4) Hello. Russell King - ARM Linux wrote: >>>>Is there any updated patch on cppi4.1 core also? >>>Is there _any_ cppi4.1 core patch anywhere? Not according to google. >>Russell, >>Here is the latest version of cppi4.1 core. >>http://patchwork.kernel.org/patch/46698/ [...] >>>If it's a USB DMA device (from the patches I can find, that seems to be >>>the case) then why can't it live in drivers/usb or drivers/dma ? >> >>CPPI4.1 DMA engine can be used either by USB or by Ethernet interface though >>currently only USB is using it but in future even Ethernet devices may use it. > drivers/dma does seem to be the right place for this. Russell, it makes me wonder why drivers/dma/ seemed the right place to you, just because of the name? :-) After spending some time on studying the infrastructure there I came to conclusion that this is not the right place because all the controllers supported there have features like memory-to-memory transfers or even RAID function offloading -- which CPPI 4.1 totally lacks (it's there purely to serve the peripherals). Adding drivers/dma/ people to this discussion in hopes they can correct me (or support me :-)... WBR, Sergei-- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
