diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index 88de17d0bd79..77b21c82faf3 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -92,10 +92,10 @@
 /* RSCFDnCFDGAFLCFG0 / RSCFDnGAFLCFG0 */
 #define RCANFD_GAFLCFG_SETRNC(gpriv, n, x) \
 	(((x) & reg_v3u(gpriv, 0x1ff, 0xff)) << \
-	 (reg_v3u(gpriv, 16, 24) - (n) * reg_v3u(gpriv, 16, 8)))
+	 (reg_v3u(gpriv, 16, 24) - ((n) & 1) * reg_v3u(gpriv, 16, 8)))
 
 #define RCANFD_GAFLCFG_GETRNC(gpriv, n, x) \
-	(((x) >> (reg_v3u(gpriv, 16, 24) - (n) * reg_v3u(gpriv, 16, 8))) & \
+	(((x) >> (reg_v3u(gpriv, 16, 24) - ((n) & 1) * reg_v3u(gpriv, 16, 8))) & \
 	 reg_v3u(gpriv, 0x1ff, 0xff))
 
 /* RSCFDnCFDGAFLECTR / RSCFDnGAFLECTR */