diff mbox series

[v1,6/7] serial: imx: stop using USR2 in FIFO reading loop

Message ID 20230201142700.4346-7-sorganov@gmail.com (mailing list archive)
State New, archived
Headers show
Series [v1,1/7] serial: imx: factor-out common code to imx_uart_soft_reset() | expand

Commit Message

Sergey Organov Feb. 1, 2023, 2:26 p.m. UTC 
The chip provides all the needed bits in the URXD0 register that we read
anyway for data, so get rid of reading USR2 and use only URXD0 bits
instead.

Signed-off-by: Sergey Organov <sorganov@gmail.com>
---
 drivers/tty/serial/imx.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)
diff mbox series

Patch

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index af4349fe6970..488d8119562e 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -892,27 +892,21 @@  static irqreturn_t __imx_uart_rxint(int irq, void *dev_id)
 	struct tty_port *port = &sport->port.state->port;
 	u32 usr2;
 
-	usr2 = imx_uart_readl(sport, USR2);
-
 	/* If we received something, check for 0xff flood */
+	usr2 = imx_uart_readl(sport, USR2);
 	if (usr2 & USR2_RDR)
 		imx_uart_check_flood(sport, usr2);
 
-	for ( ; usr2 & USR2_RDR; usr2 = imx_uart_readl(sport, USR2)) {
+	while ((rx = imx_uart_readl(sport, URXD0)) & URXD_CHARRDY) {
 		flg = TTY_NORMAL;
 		sport->port.icount.rx++;
 
-		rx = imx_uart_readl(sport, URXD0);
-
-		if (usr2 & USR2_BRCD) {
-			imx_uart_writel(sport, USR2_BRCD, USR2);
-			if (uart_handle_break(&sport->port))
-				continue;
-		}
-
 		if (unlikely(rx & URXD_ERR)) {
-			if (rx & URXD_BRK)
+			if (rx & URXD_BRK) {
 				sport->port.icount.brk++;
+				if (uart_handle_break(&sport->port))
+					continue;
+			}
 			else if (rx & URXD_PRERR)
 				sport->port.icount.parity++;
 			else if (rx & URXD_FRMERR)