[PATCH 1/1] tty: serial: imx: allow breaks to be received when using dma

Troy Kisky troy.kisky at boundarydevices.com
Fri Oct 20 15:13:40 PDT 2017


This allows me to login after sending a break when service
serial-getty at ttymxc0.service is running

Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
---
 drivers/tty/serial/imx.c | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 506fcd742b47..39033f460a24 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -934,7 +934,6 @@ static void dma_rx_callback(void *data)
 	status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state);
 
 	if (status == DMA_ERROR) {
-		dev_err(sport->port.dev, "DMA transaction error.\n");
 		clear_rx_errors(sport);
 		return;
 	}
@@ -1035,6 +1034,7 @@ static int start_rx_dma(struct imx_port *sport)
 
 static void clear_rx_errors(struct imx_port *sport)
 {
+	struct tty_port *port = &sport->port.state->port;
 	unsigned int status_usr1, status_usr2;
 
 	status_usr1 = readl(sport->port.membase + USR1);
@@ -1043,12 +1043,18 @@ static void clear_rx_errors(struct imx_port *sport)
 	if (status_usr2 & USR2_BRCD) {
 		sport->port.icount.brk++;
 		writel(USR2_BRCD, sport->port.membase + USR2);
-	} else if (status_usr1 & USR1_FRAMERR) {
-		sport->port.icount.frame++;
-		writel(USR1_FRAMERR, sport->port.membase + USR1);
-	} else if (status_usr1 & USR1_PARITYERR) {
-		sport->port.icount.parity++;
-		writel(USR1_PARITYERR, sport->port.membase + USR1);
+		if (tty_insert_flip_char(port, 0, TTY_BREAK) == 0)
+			sport->port.icount.buf_overrun++;
+		tty_flip_buffer_push(port);
+	} else {
+		dev_err(sport->port.dev, "DMA transaction error.\n");
+		if (status_usr1 & USR1_FRAMERR) {
+			sport->port.icount.frame++;
+			writel(USR1_FRAMERR, sport->port.membase + USR1);
+		} else if (status_usr1 & USR1_PARITYERR) {
+			sport->port.icount.parity++;
+			writel(USR1_PARITYERR, sport->port.membase + USR1);
+		}
 	}
 
 	if (status_usr2 & USR2_ORE) {
-- 
2.11.0




More information about the linux-arm-kernel mailing list