diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c
index 50203b82f9f5..6a3abe5b1790 100644
--- a/drivers/dma/fsl-edma-common.c
+++ b/drivers/dma/fsl-edma-common.c
@@ -92,8 +92,14 @@ static void fsl_edma3_enable_request(struct fsl_edma_chan *fsl_chan)
 
 	edma_writel_chreg(fsl_chan, val, ch_sbr);
 
-	if (flags & FSL_EDMA_DRV_HAS_CHMUX)
-		edma_writel_chreg(fsl_chan, fsl_chan->srcid, ch_mux);
+	if (flags & FSL_EDMA_DRV_HAS_CHMUX) {
+		/*
+		 * ch_mux: With the exception of 0, attempts to write a value
+		 * already in use will be forced to 0.
+		 */
+		if (!edma_readl_chreg(fsl_chan, ch_mux))
+			edma_writel_chreg(fsl_chan, fsl_chan->srcid, ch_mux);
+	}
 
 	val = edma_readl_chreg(fsl_chan, ch_csr);
 	val |= EDMA_V3_CH_CSR_ERQ;