Hi Arnd, On Wed, 11 Jul 2018 16:26:31 +0200 Arnd Bergmann <arnd at arndb.de> wrote: > On Wed, Jul 11, 2018 at 3:04 PM, Boris Brezillon > <boris.brezillon at bootlin.com> wrote: > > On Wed, 11 Jul 2018 14:26:58 +0200 > > Arnd Bergmann <arnd at arndb.de> wrote: > > > >> Compile-testing this driver on x86 caused a link error: > >> > >> ERROR: "__phys_to_dma" [drivers/mtd/nand/raw/qcom_nandc.ko] undefined! > >> > >> The problem here is that the driver attempts to convert the physical > >> address into the DMA controller as a dma_addr_t and calls phys_to_dma() > >> to do the conversion. > >> > >> However, there is no generic way to convert a phys_addr_t into a dma_addr_t > >> for anything other than RAM (which should use the dma-mapping API instead). > >> The only correct use of phys_to_dma() instead is inside of the dma-mapping > >> implementation. > > > > Should we use dma_map_resource() to do the phys_addr_t to dma_addr_t > > conversion? > > I had not seen that interface before, but yes, that does seem like the best > way to do it here. Do you plan to send a new version using dma_map_resource()? BTW, there's typo in the subject prefix (s/ranw/rawnand/). Regards, Boris