Hi, > + nr_clks = rockchip_clk_find_max_clk_id(rk3528_clk_branches, > + nr_branches) + 1; > + > + vo_grf = syscon_regmap_lookup_by_compatible("rockchip,rk3528-vo-grf"); > + if (!IS_ERR(vo_grf)) > + nr_clks = MAX(rockchip_clk_find_max_clk_id(rk3528_vo_clk_branches, > + nr_vo_branches) + 1, drivers/clk/rockchip/clk-rk3528.c: In function 'clk_rk3528_probe': drivers/clk/rockchip/clk-rk3528.c:1105:27: error: implicit declaration of function 'MAX'; did you mean 'MUX'? 1105 | nr_clks = MAX(rockchip_clk_find_max_clk_id(rk3528_vo_clk_branches, | ^~~ | MUX It seems that missing definition with older kernels. Thanks, Chukun -- 2.25.1