When built without OF support, of_match_node() expands to NULL, which produces the following output: >> drivers/dma/dw/rzn1-dmamux.c:105:34: warning: unused variable 'rzn1_dmac_match' [-Wunused-const-variable] static const struct of_device_id rzn1_dmac_match[] = { One way to silence the warning is to enclose the structure definition with an #ifdef CONFIG_OF/#endif block. Fixes: 134d9c52fca2 ("dmaengine: dw: dmamux: Introduce RZN1 DMA router support") Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx> --- Changes in v3: * Did not extend the change to the second match table as requested by Andy. * Added a Fixes tag. Changes in v2: * Used the #ifdef solution rather than the __maybe_unused keyword. drivers/dma/dw/rzn1-dmamux.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/dma/dw/rzn1-dmamux.c b/drivers/dma/dw/rzn1-dmamux.c index 0ce4fb58185e..f9912c3dd4d7 100644 --- a/drivers/dma/dw/rzn1-dmamux.c +++ b/drivers/dma/dw/rzn1-dmamux.c @@ -102,10 +102,12 @@ static void *rzn1_dmamux_route_allocate(struct of_phandle_args *dma_spec, return ERR_PTR(ret); } +#ifdef CONFIG_OF static const struct of_device_id rzn1_dmac_match[] = { { .compatible = "renesas,rzn1-dma" }, {} }; +#endif static int rzn1_dmamux_probe(struct platform_device *pdev) { -- 2.34.1