pgprot_dmachoerent() is not defined on every architecture. Having COMPILE_TEST set for the driver causes it to be compiled on architectures which do not have pgprot_dmachoerent(): drivers/misc/aspeed-lpc-ctrl.c: In function 'aspeed_lpc_ctrl_mmap': drivers/misc/aspeed-lpc-ctrl.c:51:9: error: implicit declaration of function 'pgprot_dmacoherent' [-Werror=implicit-function-declaration] prot = pgprot_dmacoherent(prot); There are two possible solutions: 1. Remove COMPILE_TEST to ensure the driver is only compiled on ARM 2. Use pgprot_noncached() instead of pgprot_dmachoerent() The first option results in less compile testing of the LPC control driver which is undesirable. The second option uses a function that is declared on all architectures and therefore should always build. Currently there is no practical difference between pgprot_noncached() and pgprot_dmachoerent() for the aspeed chips that this driver is compatible with. The reason for pgprot_dmachoerent() was that there may be chips made at some point in the future that could include hardware that pgprot_dmachoerent() could optimise for. As none of this hardware has even been announced there isn't really a need for pgprot_dmachoerent(). Using pgprot_noncached() is completely correct and optimal for all existing hardware on which the LPC control driver will run. This commit also addresses that phys_addr_t should be printed using %pap rather than %x: In file included from include/linux/miscdevice.h:6:0, from drivers/misc/aspeed-lpc-ctrl.c:11: drivers/misc/aspeed-lpc-ctrl.c: In function 'aspeed_lpc_ctrl_probe': drivers/misc/aspeed-lpc-ctrl.c:232:17: warning: format '%x' expects argument of type 'unsigned int', but argument 3 has type 'phys_addr_t {aka long long unsigned int}' [-Wformat=] dev_info(dev, "Loaded at 0x%08x (0x%08x)\n", Signed-off-by: Cyril Bur <cyrilbur@xxxxxxxxx> --- drivers/misc/aspeed-lpc-ctrl.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/misc/aspeed-lpc-ctrl.c b/drivers/misc/aspeed-lpc-ctrl.c index f6acbe1d9378..c654651a7b6d 100644 --- a/drivers/misc/aspeed-lpc-ctrl.c +++ b/drivers/misc/aspeed-lpc-ctrl.c @@ -48,7 +48,7 @@ static int aspeed_lpc_ctrl_mmap(struct file *file, struct vm_area_struct *vma) return -EINVAL; /* ast2400/2500 AHB accesses are not cache coherent */ - prot = pgprot_dmacoherent(prot); + prot = pgprot_noncached(prot); if (remap_pfn_range(vma, vma->vm_start, (lpc_ctrl->mem_base >> PAGE_SHIFT) + vma->vm_pgoff, @@ -229,8 +229,8 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev) if (rc) dev_err(dev, "Unable to register device\n"); else - dev_info(dev, "Loaded at 0x%08x (0x%08x)\n", - lpc_ctrl->mem_base, lpc_ctrl->mem_size); + dev_info(dev, "Loaded at %pap (0x%08x)\n", + &lpc_ctrl->mem_base, lpc_ctrl->mem_size); return rc; } -- 2.12.0 -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html