Not all (H)SCIF devices support DMA, and failure to set it up is not normally a cause for concern. This patch demotes the associated warning to debug output. Inspired by BSP patch "sci: sh-sci: Fix transfer sequence of unsupport DMA transfer" (6beb1f98d3bd30) by Hiromitsu Yamasaki. Signed-off-by: Ulrich Hecht <uli+renesas@xxxxxxxx> --- drivers/tty/serial/sh-sci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 426241d..ff6ba6d 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1516,7 +1516,7 @@ static struct dma_chan *sci_request_dma_chan(struct uart_port *port, chan = dma_request_slave_channel(port->dev, dir == DMA_MEM_TO_DEV ? "tx" : "rx"); if (!chan) { - dev_warn(port->dev, "dma_request_slave_channel failed\n"); + dev_dbg(port->dev, "dma_request_slave_channel failed\n"); return NULL; } -- 2.7.4