On Sunday, June 22, 2014 at 01:58:08 PM, Corentin LABBE wrote: [...] > >> + * This program is free software; you can redistribute it and/or modify > >> + * it under the terms of the GNU General Public License as published by > >> + * the Free Software Foundation version 2 of the License > > > > The license text seems incomplete. > > [...] > > I will replace it with a simplier line "Licensed under the GPL-2." I'd suggest you to use the SPDX license identifiers then, but that's not something the kernel crowd agreed upon yet IIRC.Therefore , just make the text complete please. [...] > >> + src_addr = kmap(sg_page(in_sg)) + in_sg->offset; > >> + if (src_addr == NULL) { > >> + dev_err(ss->dev, "KMAP error for src SG\n"); > >> + return -1; > >> + } > > > > Why can't you just use dma_map_sg() or somesuch ? > > I do not see why I will use a DMA function in a driver without DMA support. > Perhaps I do not know some tricks. > Can I use writel/readl on address gived by DMA API ? Oh, ok, good question -- dear list, shall one use sg_page()+kmap or sg_virt()? btw. I just noticed you're just feeding the hardware FIFO in a loop with data in the scatterlists, do I understand it correctly ? The driver will consume quite a lot of CPU time to do that, can you not implement DMA here ? [...] Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html