serial: imx: do not break from FIFO reading loop prematurely

There is no reason to prematurely break out of FIFO reading loop, and it
might cause needless reenters into ISR, so keep reading until FIFO is
empty.

Signed-off-by: Sergey Organov <sorganov@gmail.com>
Link: https://lore.kernel.org/r/20230201142700.4346-5-sorganov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index bd5d426c28fb6c6c267ea334745012760af22b9e..ef0b9d353617b62a6a63214f109ac64a2db7ca2d 100644 (file)
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -890,7 +890,7 @@ static void imx_uart_check_flood(struct imx_port *sport, u32 usr2)
 static irqreturn_t __imx_uart_rxint(int irq, void *dev_id)
 {
        struct imx_port *sport = dev_id;
-       unsigned int rx, flg, ignored = 0;
+       unsigned int rx, flg;
        struct tty_port *port = &sport->port.state->port;
        u32 usr2;
 
@@ -923,11 +923,8 @@ static irqreturn_t __imx_uart_rxint(int irq, void *dev_id)
                        if (rx & URXD_OVRRUN)
                                sport->port.icount.overrun++;
 
-                       if (rx & sport->port.ignore_status_mask) {
-                               if (++ignored > 100)
-                                       goto out;
+                       if (rx & sport->port.ignore_status_mask)
                                continue;
-                       }
 
                        rx &= (sport->port.read_status_mask | 0xFF);
 
@@ -946,13 +943,12 @@ static irqreturn_t __imx_uart_rxint(int irq, void *dev_id)
                }
 
                if (sport->port.ignore_status_mask & URXD_DUMMY_READ)
-                       goto out;
+                       continue;
 
                if (tty_insert_flip_char(port, rx, flg) == 0)
                        sport->port.icount.buf_overrun++;
        }
 
-out:
        tty_flip_buffer_push(port);
 
        return IRQ_HANDLED;