When CONFIG_HAS_IOMEM is not set/enabled, most iomap() family functions [including ioremap(), devm_ioremap(), etc.] are not available. Drivers that use these functions should depend on HAS_IOMEM so that they do not cause build errors. Cures this build error: s390-linux-ld: drivers/dma/xilinx/xilinx_dpdma.o: in function `xilinx_dpdma_probe': xilinx_dpdma.c:(.text+0x336a): undefined reference to `devm_platform_ioremap_resource' Fixes: 7cbb0c63de3fc ("dmaengine: xilinx: dpdma: Add the Xilinx DisplayPort DMA engine driver") Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> Cc: Vinod Koul <vkoul@xxxxxxxxxx> CC: dmaengine@xxxxxxxxxxxxxxx Cc: Hyun Kwon <hyun.kwon@xxxxxxxxxx> Cc: Tejas Upadhyay <tejasu@xxxxxxxxxx> Cc: Michal Simek <michal.simek@xxxxxxxxxx> Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> --- drivers/dma/Kconfig | 1 + 1 file changed, 1 insertion(+) --- linux-next-20210521.orig/drivers/dma/Kconfig +++ linux-next-20210521/drivers/dma/Kconfig @@ -702,6 +702,7 @@ config XILINX_ZYNQMP_DMA config XILINX_ZYNQMP_DPDMA tristate "Xilinx DPDMA Engine" + depends on HAS_IOMEM select DMA_ENGINE select DMA_VIRTUAL_CHANNELS help